Responses to Public Comments on the GS Notice of Data Availability and Request for 

Comment

This file contains responses to public comments on the notice of data availability and 

request for comment, organized by topic. Each topic is assigned a code (comment codes 

1000 to 6000).

The table below presents all of the EPA-assigned comment codes in the comment and 

response summary. Use the bookmarks in the PDF to move among the comment codes. 

Topic-Specific Comment Codes for the Notice of Data Availability and Request for 

Comment (74 FR 44802)

Comment Code Description Code

1. General Comments on the Notice of Data Availability 1000

1.1 Comments on the Comprehensive Approach 1100

2. Comments on Research, Data Analysis, and Findings presented in the NODA 2000

2.1 DOE Regional Carbon Sequestration Partnership Projects 2100

2.1.1. SECARB (Escatawpa, MS) 2110

2.1.2. SWP (Aneth Field, UT) 2120

2.1.3. SWP (Pump Canyon, NM) 2130

2.2. LBNL Studies 2200

2.2.1. Groundwater Quality and Mobilization of Trace Elements 2210

2.2.2. Basin-Scale Hydrologic Impacts of CO2 Storage 2220

2.3. Additional Research 2300

2.3.1. Review of Modeling Studies 2310

2.3.2. Recent Publications on Risk and Risk Management 2320

2.4. Other Research Offered by Commenters 2400

3. Injection Depth for GS Projects 3000

3.1. Comments on Concerns About Injection Depth for Class VI Wells 3100

3.1.1. National Storage Capacity 3110

3.1.2. Allowing GS in All Formation Types 3120

3.1.3. Addressing the Differences Between Class II and Class VI Wells 3130

3.2. Comments on Alternative Injection Depth Waiver Approach 3200

3.2.1. Comments Generally in Support of the Approach 3210

3.2.2. Comments in Opposition to the Approach 3220

3.2.3. Comments that Additional Submissions are Needed 3230

3.2.4. Comments that the Approach Requests Too Much Data 3240

3.3. Comments on Specific Elements of the Waiver Approach 3300

3.3.1. Site Characterization 3310

1
Comment Code Description Code

3.3.2. AoR and Corrective Action 3320

3.3.3. Emergency and Remedial Response 3330

3.3.4. Financial Responsibility 3340

3.3.5. Requirement to Submit Waiver Application to UIC and PWSS Program Directors 3350

3.3.6. Requirement to Apply for Waiver Separately from UIC Permit Application 3360

3.3.7. Notice and Hearing 3370

3.3.8. Additional Requirements Established by the UIC Director 3380

3.3.9. Comments Regarding State Discretion to Adopt the Waiver Approach 3390

3.4 Additional Information Regarding the Waiver Approach 3400

3.4.1. Applicability of Waiver Process to Deep Saline and Other Types of Formations 3410

3.4.2. Request for Information on Areas Where Injection Depth and USDWs Are a Concern 3420

3.4.3. Request for Information on Constructing Wells Through Existing CO2 Plumes 3430

4. Comments on Current State GS Activities 4000 

4.1 Comments on federal legislative actions (e.g., Waxman-Markey, IRS/Stimulus, etc.) 4100

5. Comments on the Proposed Rule (out of NODA Scope) 5000

5.1. Comments on the Proposed Permit Application Information (146.82) 5050

5.2. Comments on the Proposed Siting Requirements (146.83) 5100

5.3. Comments on the Proposed AoR and Corrective Action Requirements (146.84) 5150

5.4. Comments on the Proposed Financial Responsibility Requirements (146.85) 5200

5.5. Comments on the Proposed Construction Requirements (146.86) 5250

5.6. Comments on the Proposed Logging, Sampling, and Testing Requirements (146.87) 5300

5.7. Comments on the Proposed Operating Requirements (146.88) 5350

5.8. Comments on the Proposed MIT Requirements (146.89) 5400

5.9. Comments on the Proposed Monitoring Requirements (146.90) 5450

5.10. Comments on the Proposed Reporting Requirements (146.91) 5500

5.11. Comments on the Proposed Well Plugging Requirements (146.92) 5550

5.12. Comments on the Proposed Post-Injection Site Care Requirements (146.93) 5600

5.13. Comments on the Proposed Emergency and Remedial Response Requirements (146.94) 5650

5.14. Comments on Other Aspects of the Proposed Rule 5700

6. Other Comments that are Out of Scope for the NODA 6000

Every comment on these topic areas and the associated response is included in this 

document; there may be some repetition where multiple commenters made the same 

comment.

Responses to letters from individual commenters or organizations are also available in 

the rulemaking docket.

 

2
Comment Response Report by Comment Code

Search Terms: 

Starting EPA Comment Code: 1000 

Ending EPA Comment Code: 6000 

**************************************************************************************

**************************************************** 

EPA Comment Code: 1000 1. General Comments on the Notice of Data Availability 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jean Public 

Commenter Organization: 

EPA Letter ID: 0330 

EPA Comment ID: 27930 

Comment: firstly, i think this process is extremely dangerous. you really dont know what 

you are doing at the present time sufficiently to protect america. 

2. all of us in this nation need this conference to be available either on 

national tv or on computer software that we can join to see exactly what the 

state of the art is currently. 

3. are you drilling in chicago - is that why you want this meeting in chicago? i 

urge you to put this meeting on computer software so that people all over the 

usa are informed. this should not be a secret program, although i bet the 

politicians dont want to let the vast population know just how bad this issue is 

getting. these are my comments for the public record. 

Individual Response: The Agency does not believe that properly managed GS is dangerous. The

purpose of the Class VI requirements is to minimize and mitigate potential/identified risks through 

proper site characterization, well construction, operation, monitoring, post-injection site care, and site 

closure. The GS regulation builds upon the long-standing protective framework of the UIC Program. 

Billions of gallons of fluids have been injected for decades and EPA has been able to ensure that 

USDWs are protected in the vast majority of cases. 

EPA chose Chicago as the location for the public hearing due to its central location. A transcript of the 

hearing is available in the docket for the GS rule (see www.regulations.gov, docket number EPA-HQ3
OW-2008-0390-391). EPA also afforded all members of the public the same opportunity to comment 

online and by mail through the public docket regardless of whether they attended the hearing in 

Chicago. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28187 

Comment: We appreciate the recent NODA and the opportunity to comment on it here. Global 

Energy appreciates the analysis and development work provided to USEPA by the 

National Laboratories, and EPA’s willingness to "be adaptive" and incorporate 

beneficial results into the rule making. We encourage USEPA to proceed with the 

rule making, and feel it is important that the rule is structured in an 

adaptable manner in order to accommodate knowledge and experience over time. 

Global offers specific comments below, relative to different aspects of the 

NODA: 

1. We concur that the NODA provides helpful and informative new information and 

that USEPA should proceed with finalizing the rule. 

Individual Response: EPA is finalizing the rule and intends to follow an adaptive approach to the GS 

rulemaking to incorporate new research, data, and information about GS. For more information on the 

adaptive approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

4
EPA Letter ID: 0332 

EPA Comment ID: 28190 

Comment: 4. We strongly support the proposed "adaptive approach" to this rule, and that 

USEPA should have flexibility to implement changes that result from experience 

gained over time. 

Individual Response: EPA is finalizing the rule and intends to follow an adaptive approach to the GS 

rulemaking to incorporate new research, data, and information about GS. For more information on the 

adaptive approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28203 

Comment: It is appropriate and commendable to continue to make efforts to factor the best 

science into the proposed Class VI rule. The USEPA should be commended for their 

continued efforts - as evidenced by this NODA - to make sure that the proposed 

Class VI CO2 Injection Well regulation is based on the most up-to-date and 

comprehensive science with respect to geologic storage of anthropogenic CO2 in 

the deep subsurface. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data and information as it implements its adaptive approach to the GS rulemaking to 

incorporate new research, data, and information about GS. For more information on the adaptive 

approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

5
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27879 

Comment: AEP applauds EPA's careful approach to the development of CO2 GS regulations, 

including this most recent release of additional data. Because the technology 

contemplated in the CO2 GS proposal will not be commercially deployed for many 

years, it is essential that the final rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime incorporating performance-based 

standards in order to allow for site-tailored requirements that will reflect the 

vast differences among various potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes:

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara A. Walz 

Commenter Organization: Tri-State Generation and Transmission Association, Inc. (Tri-State) 

EPA Letter ID: 0346 

EPA Comment ID: 27888 

6
Comment: Tri-State applauds EPA's careful approach to the development of CO2 GS 

regulations, including this most recent release of additional data. Because the 

technology contemplated in the CO2 GS proposal is not currently commercially 

deployed, it is essential a Final Rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime in order to allow for 

site tailored requirements that will reflect the vast differences among various 

potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James F. Stine 

Commenter Organization: National Rural Electric Cooperative Association 

EPA Letter ID: 0348 

EPA Comment ID: 27904 

Comment: At the outset, NRECA applauds EPA's careful approach to the development of CO2 

GS regulations, including this most recent release of additional data. We urge 

EPA to continue developing these regulations with a particular emphasis on 

insuring that the final requirements are not so onerous as to effectively make 

CCS unaffordable. Because the technology contemplated in the CO2 GS proposal 

will not be commercially deployed for many years, it is essential the Final Rule 

be flexible enough to accommodate developments in information and technology 

7
related to carbon sequestration. It is critical that EPA develop a regulatory 

regime incorporating performance-based standards in order to allow for sitetailored requirements that will reflect the vast differences among various 

potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data,

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James R. Roewer 

Commenter Organization: Utility Solid Waste Activities Group (USWAG) 

EPA Letter ID: 0349 

EPA Comment ID: 28033 

Comment: At the outset, USWAG applauds EPA's careful approach to the development of CO2 

GS regulations, including this most recent release of additional data. As 

USWAG's comments on the proposed rule emphasized, it is essential the Final Rule 

be flexible enough to accommodate developments in information and technology 

related to carbon sequestration, particularly because the technology 

contemplated in the proposal will not be commercially deployed for many years. 

USWAG's comments urged EPA to develop a regulatory regime incorporating 

performance- based standards in order to allow for site-tailored requirements 

that will reflect the vast differences among various potential CO2 GS sites. 

8
Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Claire M. Olson 

Commenter Organization: Basin Electric Power Cooperative (Basin Electric) 

EPA Letter ID: 0351 

EPA Comment ID: 28054 

Comment: Basin Electric applauds EPA's careful approach to the development of CO2 GS 

regulations, including this most recent release of additional data. Because the 

technology contemplated in the CO2 GS proposal will not be commercially deployed 

for many years, it is essential the Final Rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime incorporating performance-based 

standards in order to allow for site-tailored requirements that will reflect the 

vast differences among various potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

9
EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28071 

Comment: At the outset, Ameren applauds EPA's careful approach to the development of CO2 

as regulations, including this most recent release of additional data. Because 

the technology contemplated in the CO2 GS proposal will not be commercially 

deployed for many years, it is essential the Final Rule be flexible enough to 

accommodate developments in information and technology related to carbon 

sequestration. It is critical that EPA develop a regulatory regime incorporating 

performance-based standards in order to allow for site-tailored requirements 

that will reflect the vast differences among various potential CO2 as sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

10
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John A. Gulvas 

Commenter Organization: Consumers Energy (CE) 

EPA Letter ID: 0356 

EPA Comment ID: 28087 

Comment: CE supports EPA’s careful approach to the development of CO2 GS regulations, 

including this most recent release of additional data. Because the technology 

contemplated in the CO2 GS proposal will not be commercially deployed for many 

years, it is essential the Final Rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime incorporating performance-based 

standards in order to allow for site-tailored requirements that will reflect the 

vast differences among various potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. 

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

11
EPA Letter ID: 0360 

EPA Comment ID: 28239 

Other EPA Comment Codes and Descriptions: 5000 5. Comments on the Proposed Rule (out of 

NODA Scope) 

Comment: At the outset, NRG applauds EPA’s careful approach to the development of CO2 GS 

regulations, including this most recent release of additional data. Because the 

technology contemplated in the CO2 GS proposal will not be commercially deployed 

for many years, it is essential the Final Rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime incorporating performance-based 

standards in order to allow for site-tailored requirements that will reflect the 

vast differences among various potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. EPA plans to, every six years, collect and review data on GS 

projects to determine whether the appropriate amount and types of information and appropriate 

documentation are being collected, and to determine if modifications to the requirements are 

appropriate or necessary.

EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 30-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Smith 

Commenter Organization: Questar Exploration & Production Company 

EPA Letter ID: 0374 

EPA Comment ID: 28117 

12
Comment: The preliminary field data from DOE-sponsored projects, GS-related research and 

changes EPA is proposing for injection depth requirements for Class VI wells 

demonstrate that while there is much to be learned about long-term sequestration 

of Carbon Dioxide, there is a lot we already know about the safe injection of 

Carbon Dioxide for enhanced oil and gas recovery. Given that, it is important to 

draft the upcoming rules in a way that recognizes the continuation and 

appropriateness of the existing enhanced oil and gas recovery Class II permit 

while providing enough flexibility in the new Class VI permit to allow GS to 

move forward in a safe and economic way. In this regard, Questar adopts and 

incorporates herein the various documents that make up the comments on the 

underlying rule submitted by API on December 23,2008. 

Individual Response: EPA recognizes that the oil and gas industry has decades of experience 

injecting CO2 for the purpose of ER. The GS rulemaking builds upon existing experience and 

knowledge about safe injection practices in ER and other injection industries, with tailored 

requirements that address the unique nature of CO2 injection for GS. 

The final rule does not preclude CO2 injection for ER under Class II permits. However, the rule 

requires re-permitting of Class II wells (as Class VI) if the primary purpose of the injection transitions 

from ER to long-term storage, and establishes specific, risk-based criteria to be considered by the 

Director in making this determination (§144.19). For more information on the transition from Class II 

to Class VI, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28168 

Comment: EPA has not proposed changes, in the NODA, to any of the regulatory language 

included in the Notice of Proposed Rulemaking. Therefore, we assume that the 

"definitions' included in the NODA are meant for clarity only, and do not 

indicate any intention by the Agency to change those definitions. Unfortunately 

clarity is not always achieved: we note particularly the new definition of 

"carbon capture and storage" [FOOTNOTE 6] which is not found in the proposed 

13
regulatory text and confusingly includes the word "storage" rather than 

"sequestration" making it inconsistent with the regulatory text as proposed, as 

well as other definitions set out in the NODA. 

FOOTNOTE 6 - 74 Fed. Reg. 44803. 

In addition, we refer EPA to our previous joint comments of December 2008 and 

the Multi- Stakeholder Group letter of May 14, 2009 for specific recommendations 

on regulatory language changes to the proposed definitions. 

"Carbon dioxide stream means carbon dioxide plus incidental associated 

substances derived from the source of the CO2 and/or the capture process, and 

any substances added to the stream to enable or improve the injection process. 

This subpart does not apply to any carbon dioxide stream that meets the 

definition of a hazardous waste under 40 CFR part 261." 

"Confining zone means a geological formation, group of formations, or part of a 

formation that is capable of limiting fluid movement from an injection zone." 

"Sequestration project [...] It includes the subsurface three-dimensional extent of 

the carbon dioxide plume, associated pressure front, and displaced formation 

fluids, as well as the surface area above that delineated region." 

"Geologic sequestration project means an injection well or wells used to emplace 

a carbon dioxide stream into an injection zone for geologic sequestration." 

"Transmissive fault or fracture means a fault or fracture that has sufficient 

permeability and vertical extent to allow fluids to move beyond a confining 

zone." 

"Area of review means the subsurface three-dimensional extent of the carbon 

dioxide stream plume and the associated pressure front, as well as the overlying 

formations, any USDWs underlying an injection zone along with any intervening 

formations, and the surface area above that delineated region." 

Individual Response: EPA did not include a definition for carbon capture and storage in the 

proposed or final GS rule, although, the final GS rule includes some revised definitions in response to 

public comments. The definitions, including the definition of a GS project, can be found at 40 CFR 

146.81(d). For details on specific definitions, see the responses to comments on the proposed rule in 

the rulemaking docket. 

14
EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28178 

Comment: E. Conclusion 

Our organizations appreciate the opportunity to provide comments to EPA on this 

most important rulemaking effort. A final rule will represent a significant step 

forward in combating global climate change, and the time is more than ripe for 

the U.S. to take such steps. When EPA issues its final rule, we feel it must be 

both technically sound and adaptive to reflect learning from experience with GS 

projects in as seamless a manner as is possible. We very much look forward to 

continuing to work with the Agency on this rule, as well as other efforts under 

the Agency’s existing authority to address the significant problem of climate 

change in the near term. 

Individual Response: EPA believes that the final GS rule is technically sound and that the adaptive 

approach to the GS rulemaking will allow for the incorporation of new research, data, and information 

about GS as it becomes available in the future. For more information on the adaptive approach, see 

the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28090 

15
Comment: The Notice of Data Availability (NODA) references useful new studies that can 

help to inform EPA’s proposed rule-making for geologic storage of CO2. However, 

Anadarko Petroleum Corporation (APC) sees nothing in the new information that 

suggests that EPA should depart from the adaptive approach to regulation that 

EPA has discussed as the basic objective for the geologic sequestration (GS) 

rule. Adherence to an adaptive approach for regulations will facilitate new 

information being implemented in a responsible way. The proven success of 30+ 

years of CO2 enhanced oil recovery, 70+ years of natural gas storage, and 150 

years of oil and gas production, demonstrates the industry knows how to safely 

and effectively drill wells, inject and store fluids, and monitor for 

containment. In addition, CO2 injection for purposes of enhanced oil or gas 

recovery ("EOR/EGR") has been successfully regulated as Class II injection for 

decades, and we agree with EPA that there is nothing to justify any disruption 

of the existing regulatory regime for the thousands of injection wells already 

in use in these operations. 

Individual Response: EPA is following an adaptive approach to the GS rulemaking to incorporate 

new research, data, and information about GS. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. For additional information on the adaptive approach, see the 

responses to comments on the proposed rule in the rulemaking docket.

EPA recognizes that the oil and gas industry has decades of experience injecting CO2 for the purpose 

of ER. The GS rulemaking builds upon existing experience and knowledge about safe injection 

practices in ER and other injection industries, with tailored requirements that address the unique 

nature of CO2 injection for GS. 

The final rule does not preclude CO2 injection for ER under Class II permits. However, the rule 

requires re-permitting of Class II wells (as Class VI) if the primary purpose of the injection transitions 

from ER to long-term storage, and establishes specific, risk-based criteria to be considered by the 

Director in making this determination (§144.19). For more information on the transition from Class II 

to Class VI, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

16
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27952 

Comment: Comment No.1 

Page 44803 

Issue Topic from EPA's NODA 

Availability of this new information could change EPA's approach to the final 

rulemaking. 

Carbon Sequestration Council Comments 

The Carbon Sequestration Council ("the Council") has reviewed the Notice of Data 

Availability (NODA) and the accompanying data and results presented for public 

review and comment. We see nothing in the new information that suggests that 

EPA should depart from the adaptive approach to regulation that EPA has 

discussed as the basic objective for the geologic sequestration (GS) rule. 

Individual Response: EPA clarifies that it is following an adaptive approach to the GS rulemaking to 

incorporate new research, data, and information about GS. For more information on the adaptive 

approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28121 

17
Comment: Carbon capture and storage (CCS) is a critical element in the full portfolio of 

options needed not only to reduce CO2 emissions, but also to ensure continued 

affordable and reliable electric service to customers throughout the nation. 

The commercial availability of CCS depends upon the development of clear, 

flexible, and appropriately tailored regulatory regimes that will facilitate 

development of and investment in CCS technology and projects while protecting 

against potential environmental risks. We commend the Agency for its continued 

efforts to establish such a regime for GS and its efforts to balance the 

availability of new data with the need for regulatory certainty. Information 

about GS currently available can form the basis of an effective and safe 

regulatory program. 

Individual Response: EPA agrees it is important to balance updated information with regulatory 

certainty. EPA is following an adaptive approach to the GS rulemaking to incorporate new research, 

data, and information about GS. For more information on the adaptive approach, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28152 

Comment: Conclusion 

The promise of GS as a strategy to address climate change and promote national 

energy security hinges on resolving regulatory uncertainty in a way that 

protects and the public and the environment without placing an unreasonable 

burden on site owners and operators that would effectively prevent the 

development of commercial-scale CCS projects in the United States. Existing 

market dynamics and economic realities must be considered in the process to 

address the regulatory uncertainty surrounding post-injection site care, 

financial assurance, and long-term liability. This issue effectively boils down 

to four overarching questions confronting entities involved in the capture, 

transport, injection, and storage of CO2: (1) length of the post-injection site 

18
care time period; (2) aspects of post-injection site care for which entities 

will be responsible; (3) availability and suitability of different risk 

management instruments for meeting financial assurance requirements; and (4) 

permanent transfer of all liability to the State, as no company can or will 

accept indefinite long term liability. 

Individual Response: EPA clarifies that the purpose of the GS rule is to ensure that where GS 

technology is deployed, it is done in a manner that is protective of USDWs. Under the authority of the 

SDWA, the rule does not promote specific technologies, nor does it address climate change or promote 

specific national energy security initiatives. For additional responses related to the post-injection site 

care time frame; responsibilities related to aspects of post-injection site care; availability and 

suitability risk management instruments for meeting financial assurance requirements; and permanent 

transfer of liability to the State, see the responses to comments on the proposed rule in the 

rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 1100 1.1 Comments on the Comprehensive Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28189 

Comment: 3. We do not support the view of other commenter’s that more rigorous attention 

to RCRA and CERCLA are necessary or appropriate. The rule already prohibits 

19
injection of the regulated wastes, as well as injection stream characterization 

that will demonstrate that these characteristics are avoided. This is a CO2 

injection rule not a waste management rule. Regular update of the stream 

qualities is reasonable, without making the process overly burdened. 

As we noted in our earlier comments, if the requirements are too onerous GS of 

CO2 will not occur as desired. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

Regarding RCRA, the final GS rule requires owners or operators to characterize their CO2 stream as 

part of their permit application process to determine whether the injectate is a RCRA hazardous waste. 

If the CO2 stream is determined to be a hazardous waste, injection may only occur in a Class I 

hazardous waste injection well. Additionally, EPA clarifies that a determination as to whether the 

presence of hazardous substances in CO2 results in CERCLA liability from a sequestration facility 

depends entirely on the composition of the specific CO2 stream and the environmental media in which 

it is stored (e.g., soil or ground water). For additional information, see the preamble to the final rule 

and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

20
EPA Letter ID: 0334 

EPA Comment ID: 28204 

Other EPA Comment Codes and Descriptions: 5000 5. Comments on the Proposed Rule (out of 

NODA Scope) 

Comment: Completion of the proposed Class VI well rule should not be tied to the 

resolution of future US climate policy. The USEPA should also be commended for 

moving forward with the standalone proposed Class VI UIC rule even though there 

is a strong desire (and indeed a need) from many stakeholders to understand how 

this proposed Class VI rule would fit into a larger national climate change 

mitigation policy. While it is undoubtedly true that in a perfect world, it 

would be best if the nation’s future climate policy was fully articulated before 

the final Class VI rule were promulgated, we do not live in such a perfect 

world. And just as it is clear that the Class VI rule will need to be changed 

and revised over time as we learn more about commercial scale geologic CO2 

storage, it is also clear that the same kind of "adaptive regulatory approach" 

will be needed for the larger national climate policy as we learn more about the 

potential of various mitigation options as well as the extent and pace of 

negative climatic impacts. Therefore, it is wise to proceed with this rule as 

discussed in "Section II. What Did EPA Propose?" of the NODA (p. 44805). 

Individual Response: The Agency is using an adaptive approach to ensure USDW protection and 

meet the potentially fast pace of GS deployment. EPA believes that an adaptive approach will allow 

regulatory development to proceed in time to meet the current and future demand for Class VI 

permits while recognizing the need to continue to gather data from pilot projects and other research 

as it becomes available; as well as to enhance understanding of the technical and administrative 

aspects of GS deployment, operation, and technology developments. The Agency plans to collect and 

review data every six years on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary.

The issue of climate policy is outside the scope of the Notice of Data Availability and the UIC 

Program’s authority under the GS rulemaking. For more information on the GS requirements and the 

UIC program, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

21
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Patrick J. Nugent 

Commenter Organization: Texas Pipeline Association (TPA) 

EPA Letter ID: 0340 

EPA Comment ID: 28017 

Comment: 4. EPA should not go beyond the Safe Drinking Water Act in the development of 

geologic sequestration regulations. TPA is concerned about the NODA's statement 

that EPA is considering an expanded regulatory framework that might go beyond 

the Safe Drinking Water Act ("SDWA") and could include regulations pursuant to 

the Clean Air Act, the Resource Conservation and Recovery Act ("RCRA"), and the 

Comprehensive Environmental Response, Compensation, and Liability Act 

("CERCLA"). 74 Fed. Reg. 44805. Carbon dioxide injectate should be categorized 

as a commodity, not a waste or pollutant. Sequestered carbon dioxide is expected 

to generate a credit in any future carbon credit scheme. Characterization of the 

carbon dioxide stream as a waste or pollutant, and imposition of regulations 

under the Clean Air Act, RCRA or CERCLA, would be viewed as exposing industry 

participants to severe and open-ended liability and, as such, would dramatically 

reduce the number of companies willing to engage in geologic sequestration under 

the new regulatory scheme. In this as in all areas of the proposed rules, EPA 

should bear in mind that the benefits associated with geologic sequestration 

will not be realized if unnecessarily burdensome regulations and financial 

liability risks are imposed upon those who engage in geologic sequestration. 

Individual Response: EPA acknowledges that regulatory clarity is essential for enabling GS to move 

forward in a manner that protects human health and the environment. In developing the final GS rule, 

the Office of Water coordinated with other Agency program offices and across federal agencies (e.g., 

with the Department of Energy; United States Geological Survey; Bureau of Ocean Energy 

Management, Regulation, and Enforcement, formerly the Minerals Management Service; Bureau of 

Land Management). The Agency continues to evaluate areas of potential applicability of other Federal 

environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and 

Recovery Act; the Comprehensive Environmental Response, Compensation, and Liability Act; and the 

Marine Protection, Research and Sanctuaries Act to various aspects of GS and CCS. The Agency will 

continue to coordinate on GS and CCS related issues to minimize redundancy and maximize 

efficiencies for owners or operators. For additional information, please see the discussion entitled 

"How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS Activities?" in the 

preamble to the final GS rule.

22
Regarding RCRA, the final GS rule requires owners or operators to characterize their CO2 stream as 

part of their permit application process to determine whether the injectate is a RCRA hazardous waste. 

If the CO2 stream is determined to be a hazardous waste, injection may only occur in a Class I 

hazardous waste injection well. Additionally, EPA clarifies that a determination as to whether the 

presence of hazardous substances in CO2 results in CERCLA liability from a sequestration facility 

depends entirely on the composition of the specific CO2 stream and the environmental media in which 

it is stored (e.g., soil or ground water). EPA clarifies that the GS rule does not address the status of 

CO2 as either a pollutant or a commodity. For additional information, see the preamble to the final 

rule and the responses to comments on the proposed GS rule.

The Agency further clarifies that the GS rule does not address issues related to carbon crediting. The 

Greenhouse Gas Reporting Rule for CO2 Injection and Geologic Sequestration (40 CFR 98), issued 

under the authority of the CAA in a separate rulemaking action requires that sources above certain 

threshold emission levels monitor and report their emissions. In a separate action, EPA is amending 

40 CFR part 98, which provides the regulatory framework for the GHG Reporting Program, to add 

reporting requirements covering facilities that conduct GS (in subpart RR) and all other facilities that 

inject CO2 underground (subpart UU). This data will inform Agency policy decisions under CAA related 

to the use of CCS for mitigating GHG emissions. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28076 

Comment: The NODA notes that many commenters on the proposed rule encouraged the Agency 

to consider a more "comprehensive framework" for GS, addressing issues arising 

under statutes other than SDWA, such as the Clean Air Act, the Resource 

Conservation and Recovery Act, and the Comprehensive Environmental Response, 

Compensation and Liability Act. It further states that the Agency "is currently 

evaluating the need for a more comprehensive regulatory framework," and that if 

the Agency "chooses to pursue" such a framework, it will seek public comment on 

any proposal it develops. 74 Fed. Reg. at 44805 

At the same time, while separate regulations for CCS are to some extent 

necessary, Ameren encourages the Agency to avoid piecemeal regulation to the 

23
extent possible and develop a single rule to address issues arising outside the 

SDWA context. In the last year, the Agency has considered various provisions 

directly impacting CCS projects under the Agency's proposed rule on Mandatory 

Reporting of Greenhouse Gases (Docket ID No. EPA-HQ-ORA-2008-0508), 74 Fed. Reg. 

16448 (April 10, 2009), as well as its proposed changes to the Renewable Fuel 

Standard (RFS) Program (Docket ID No. EPA-HQ-OAR-20050161), 74 Fed. Reg. 24904 

(May 26, 2009), raising concerns that CCS may be unnecessarily governed through 

a patchwork of separate provisions. A holistic approach to CCS to the greatest 

extent possible is of critical importance to ensuring efficient development and 

commercial deployment of CCS technologies. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28220 

Comment: Clearly, a viable large-scale commercial CCS program requires resolution of a 

broad range of technical, policy and legal questions, most of which are beyond 

the scope of this rulemaking. That said, we think the Agency’s efforts here are 

an important first step and will set the tone for how EPA, other federal and 

24
state regulatory bodies and the public will approach CCS going forward. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; and 

the Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research, and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS-related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28232 

Comment: 5. Avoid Regulatory Creep. We are extremely concerned by arguments that the 

whole suite of environmental laws -- including the Comprehensive Environmental 

Response, Compensation, and Liability Act ("CERCLA") and the Resource 

Conservation and Recovery Act ("RCRA") -- be applied to CCS projects. 

These laws, if applied broadly to CCS, would impose significant obligations and 

potential liabilities not only on project operators, but also potentially on 

other entities in the CO2 chain, such as entities producing the CO2 that is 

ultimately injected. That would put advancement of CCS commercialization into a 

deep freeze. Such an outcome would clearly be counter-productive. Thus, we 

urge the Agency to pursue options that will limit CCS projects’ liability under 

CERCLA and RCRA. 

25
6. Put Limits on EPA Authority and Discretion. The Agency notes in its 

supplement that it is currently evaluating the need for a more comprehensive 

regulatory framework to provide legal guidance regarding emerging CCS 

technology. 

The Roundtable fully recognizes the difficulty EPA faces in establishing 

regulations for CCS. We fully support the notion that some level of discretion 

is necessary for the Agency to adjust to changes or new information that emerges 

as pilot projects move forward. Having said that, the balance here is a 

delicate one. Too much discretion can undermine the certainty that is so 

important to encourage CCS projects. Certainly, any discretion that is afforded 

should be bound by reasonable criteria. Equally important: EPA should adhere 

to its limited authority under the SDWA and not use this as an opportunity to 

seek to extend it. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

Regarding RCRA, the final GS rule requires owners or operators to characterize their CO2 stream as 

part of their permit application process to determine whether the injectate is a RCRA hazardous waste. 

If the CO2 stream is determined to be a hazardous waste, injection may only occur in a Class I 

hazardous waste injection well. Additionally, EPA clarifies that a determination as to whether the 

presence of hazardous substances in CO2 results in CERCLA liability from a sequestration facility 

depends entirely on the composition of the specific CO2 stream and the environmental media in which 

it is stored (e.g., soil or ground water). For additional information, see the preamble to the final rule 

and the responses to comments on the proposed GS rule.

EPA disagrees that it is attempting to extend its authority under the SDWA. The GS regulation, which 

addresses the injection of CO2 for the purpose of protecting USDWs, is within EPA’s authority under 

26
the SDWA. For more information on EPA’s authority to regulate GS, see the responses to comments 

on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Pamela F. Faggert 

Commenter Organization: Dominion Resources Services, Inc. 

EPA Letter ID: 0358 

EPA Comment ID: 28236 

Comment: Comments on a Cumulative Regulatory Framework 

The NODA states that EPA is evaluating the need for a more comprehensive 

regulatory framework for geologic storage in order to address issues arising 

under statutes other than SDWA, such as the Clean Air Act (CAA), the Resource 

Conservation and Recovery Act (RCRA) and the Comprehensive Environmental 

Response Compensation and Liability Act (CERCLA). While separate regulatory 

structures for CCS may be necessary to some degree, we encourage EPA to avoid 

piecemeal regulation and to pursue a holistic approach to the greatest extent 

possible. Such an approach is critical to ensuring regulatory certainty and 

efficient development and commercial deployment of CCS technologies. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

27
Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28245 

Comment: Need for a more comprehensive regulatory framework for geological sequestration 

beyond the scope of the Safe Drinking Water Act 

The NODA states that in response to the July 25, 2008 proposed rule, "Federal 

Requirements Under the Underground Injection Control (UIC) Program for Carbon 

Dioxide (CO2) Geological Sequestration (GS) Wells," EP A received a number of 

comments recommending that the Agency explore environmental and regulatory 

issues beyond the scope of the proposed Safe Drinking Water Act requirements for 

underground injection of CO2 for geological sequestration. 

The NODA states that EP A is currently evaluating the need for a more 

comprehensive regulatory framework for as sequestration, and that in developing 

such a framework, the Agency would consider the potential applicability of other 

Federal environmental statutes such as the Clean Air Act, the Resource 

Conservation and Recovery Act, the Comprehensive Environmental Response, 

Compensation, and Liability Act; and the Clean Water Act to various aspects of 

geologic sequestration of CO2° 

We add our voice to those commenters who have urged the Administrator to pursue 

a more comprehensive regulatory approach to as rulemaking. In particular, we 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; and 

the Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

28
Liability Act; and the Marine Protection, Research, and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. 

Regarding sub-seabed GS, EPA clarifies that sub-seabed CO2 injection for GS may, in certain 

circumstances, be defined as ocean dumping and subject to regulation under the Marine Protection, 

Research, and Sanctuaries Act. EPA adds that the Bureau of Ocean Energy Management, Regulation, 

and Enforcement (BOEM), formerly the Minerals Management Service, administers the Outer 

Continental Shelf Lands Act (OCSLA), which provides for the grant of leases, easements, or rights-ofway on the outer continental shelf to the extent that an activity “supports production, transportation, 

or transmission of energy from sources other than oil and gas” and complies with the other provisions 

of OCSLA section 8(p). 

For additional information, please see the discussion entitled "How Does This Rulemaking Relate to 

Other Federal Authorities and GS and CCS Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28247 

Other EPA Comment Codes and Descriptions: 6000 6. Other Comments that are Out of Scope for 

the NODA 

Comment: Regulation under a more comprehensive regulatory framework 

The July 25, 2005 proposed rule indicates that wells up to three miles offshore 

may be subject to other authorities or may require approval under other 

authorities. It appears from the proposal that wells located outside of State 

territorial waters would not be regulated under this proposal. We recommend that 

EP A consider the potential applicability of Federal Statutes that would address 

various aspects of sub-seabed as both in State and Federal waters in its 

rulemaking. 

29
Individual Response: The GS rulemaking, promulgated under SDWA authority, applies to owners 

and operators of injection wells used for GS of CO2, including those in state territorial waters. 

Injection wells outside of state territorial waters may be subject to other federal authorities. For 

example, sub-seabed CO2 injection for GS may, in certain circumstances, be defined as ocean 

dumping and subject to regulation under the Marine Protection, Research, and Sanctuaries Act. EPA 

adds that the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEM), formerly 

the Minerals Management Service, administers the Outer Continental Shelf Lands Act (OCSLA), which 

provides for the grant of leases, easements, or rights-of-way on the outer continental shelf to the 

extent that an activity “supports production, transportation, or transmission of energy from sources 

other than oil and gas” and complies with the other provisions of OCSLA section 8(p). 

EPA acknowledges that GS falls within the broader context of CCS and the need for regulatory clarity 

to ensure that USDWs are protected from endangerment. In developing the final GS rule, the Office of 

Water coordinated with other Agency program offices and across federal agencies (e.g., with the 

Department of Energy; United States Geological Survey; Bureau of Ocean Energy Management, 

Regulation, and Enforcement, formerly the Minerals Management Service; and the Bureau of Land 

Management). The Agency continues to evaluate areas of potential applicability of other Federal 

environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and 

Recovery Act; the Comprehensive Environmental Response, Compensation, and Liability Act; and the 

Marine Protection, Research, and Sanctuaries Act to various aspects of GS and CCS. The Agency will 

continue to coordinate on GS and CCS-related issues to minimize redundancy and maximize 

efficiencies for owners or operators. For additional information, please see the discussion entitled 

"How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS Activities?" in the 

preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28259 

Comment: In addition to specific comments on the Agency's proposed revisions to the 

siting provisions, NACCSA offers specific comments on the Agency's project and 

research updates. NACCSA further offers support for the concept of a 

comprehensive regulatory framework for CO2 capture and storage and for 

recognizing and rewarding state efforts to move forward with bringing regulatory 

30
certainty to CCS. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28267 

Comment: c. Comprehensive Regulatory Framework for GS 

As noted in NACCSA's prior comments, issues related to long-term liability and 

property rights potentially associated with CCS projects will remain to be 

resolved despite the Agency's UIC rulemaking efforts, and resolution of those 

issues may be critical to initiation of CCS progress. The NODA's recognition of 

these and other issues related to CCS projects, including potential issues 

arising under the Clean Air Act, RCRA, and CERCLA,[FOOTNOTE 3] and its statement 

that the Agency "is currently evaluating the need for a more comprehensive 

regulatory framework, is notable and appreciated in this regard. EPA's efforts 

will raise stakeholder and policy maker awareness on these critical issues so 

necessary to the successful commercial deployment of CCS. 

FOOTNOTE 3 NACCSA's previous comments include a discussion of regulatory and 

31
liability issues related to potential application of CERCLA and RCRA to the GS 

context and the need for their separate treatment by the Agency. 

NACCSA also notes the importance of a single framework, to the extent possible, 

for CCS. While separate regulatory structures for CCS are to some extent 

necessary - and the UIC context, in which the Agency's authority is statutorily 

limited, provides a good example - the Agency is encouraged to approach 

regulation holistically and avoid piecemeal regulation. We note that Agency's 

final rule on Mandatory Reporting of Greenhouse Gases (Docket ID No. EPA-HQORA-2008-0508), released on September 22, 2009, references the Agency's intent 

to "issue a new proposal" on GS, and that its proposed changes to the Renewable 

Fuel Standard (RFS) Program (Docket ID No. EPA-HQ-OAR-2005-0161), 74 Fed. Reg. 

24904 (May 26, 2009), also implicates potential regulatory requirements for CCS, 

bringing these concerns of piecemeal regulation closer to reality. NACCSA would 

welcome the opportunity to work with EPA in crafting comprehensive provisions 

for CCS. 

The NODA also states that should the Agency decide to pursue a comprehensive 

regulatory framework for CCS, it will "endeavor to issue a more comprehensive 

rule in the same time frame as it had planned for the stand-alone UIC GS 

rulemaking." NACCSA agrees with the Agency that providing regulatory clarity on 

all possible issues at the outset is ideal. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

32
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28165 

Comment: for injected CO2 [FOOTNOTE 1]. We are somewhat encouraged by EPA’s statements 

in this NODA that it is "evaluating the need for a more comprehensive regulatory 

framework to provide legal guidance," and that it will take comment on and 

"endeavor to issue a more comprehensive rule in the same time frame" as the 

final rule in this docket. [FOOTNOTE 2] Our organizations anticipate the 

opportunity to provide input to the Agency when such a rule is proposed. 

However, EPA’s good intentions do not obviate the need for the Agency to add a 

clear statement of Clean Air Act authority when it finalizes this rule, as we 

have noted in our earlier comments is necessary. 

FOOTNOTE 1- For further details, refer to our letter of Jun 26, 2009 to 

Administrator Jackson. 

FOOTNOTE 2- 74 Fed. Reg, at 44805; see also Final Rule, Mandatory Reporting of 

Greenhouse Gases, EPA-HQ-OAR-2008-0508, RIN 2060-A079, as signed, at 480-481 

(Sept. 23, 2009). 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

The Agency further clarifies that comments on the Greenhouse Gas Reporting Rule for CO2 Injection 

and Geologic Sequestration (40 CFR 98), issued under the authority of the CAA in a separate 

33
rulemaking action are out of the scope of the GS NODA. For additional information, see the responses 

to comments on the proposed GHG rule in the rulemaking docket for that rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28127 

Comment: Finally, to further foster the development and deployment of CCS, a single rule 

is needed to address issues arising outside the SDWA context in order to avoid 

piecemeal regulation. EEI would welcome the opportunity to work with EPA in 

crafting such a rule. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA acknowledges commenters’ concerns regarding the need for a single regulatory approach, and 

clarifies that its authority related to GS wells is limited under SDWA. EPA encourages states to seek 

primacy for GS, because states have authority to address challenges and issues that are outside of the 

scope of the SDWA authority. For more information on primacy, see the responses to comments on 

the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

34
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28141 

Comment: c. Comprehensive Regulatory Framework for GS 

The NODA notes that many commenters on the proposed rule encouraged the Agency 

to consider a more "comprehensive framework" for GS, addressing issues arising 

under statutes other than SDWA, such as the Clean Air Act (CAA), the Resource 

Conservation and Recovery Act (RCRA), and the Comprehensive Environmental 

Response, Compensation and Liability Act (CERCLA).[Footnote 12] It further 

states that the Agency "is currently evaluating the need for a more 

comprehensive regulatory framework," and that if the Agency "chooses to pursue" 

such a framework, it will seek public comment on any proposal it 

develops.[Footnote 13] 

[Footnote 12] EEI’s previous comments include a discussion of regulatory and 

liability issues related to potential application of CERCLA and RCRA to the GS 

context and the need for their separate treatment by the Agency. 

[Footnote 13] 74 Fed. Reg. at 44805. 

The Agency should to adhere to its limited jurisdiction under SDWA in 

promulgating UIC rules for GS, in order to help achieve a regulatory framework 

that is stable and not subject to legal challenge based on lack of authority. 

At the same time, while separate regulatory structures for CCS are to some 

extent necessary, a single rule is needed to address issues arising outside the 

SDWA context in order to avoid piecemeal regulation. In the last year, the 

Agency has considered various provisions directly impacting CCS projects under 

the Agency’s proposed rule on Mandatory Reporting of Greenhouse Gases (Docket ID 

No. EPA-HQ-ORA-2008-0508), 74 Fed. Reg. 16448 (April 10, 2009), as well as its 

proposed changes to the Renewable Fuel Standard (RFS) Program (Docket ID No. 

EPA-HQ-OAR-2005-0161), 74 Fed. Reg. 24904 (May 26, 2009), raising concrete 

concerns that CCS may be unnecessarily governed through a patchwork of separate 

provisions. A holistic approach to CCS to the greatest extent possible is of 

35
critical importance to ensuring efficient development and commercial deployment 

of CCS technologies. EEI would welcome the opportunity to work with EPA in 

crafting a rule that appropriately addresses CCS. 

The NODA states that should the Agency pursue this approach, it will "endeavor 

to issue a more comprehensive rule in the same time frame as it had planned for 

the stand-alone UIC GS rulemaking." [Footnote 14] The sooner regulatory 

certainty can be provided, the more it will assist development and deployment of 

commercial-scale CCS as a tool to combat climate change while ensuring reliable, 

affordable energy for the country going forward. 

[Footnote 14] Id. In the final rule for the Mandatory Reporting of Greenhouse 

Gases, which was signed on September 22, 2009, but has not yet appeared in the 

Federal Register, EPA noted that it would soon undertake a new rulemaking for 

CO2 GS sites under the CAA. EEI supports the development of comprehensive 

rulemaking that would provide regulatory certainty for CCS projects without 

imposing additional or unnecessary regulatory requirements. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA acknowledges commenters’ concerns regarding the need for a single regulatory approach, and 

clarifies that its authority related to GS wells is limited under SDWA. EPA encourages states to seek 

primacy for GS, because states have authority to address challenges and issues that are outside of the 

scope of the SDWA authority. For more information on primacy, see the responses to comments on 

the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

36
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28150 

Comment: III. Comments on the need for a more comprehensive regulatory framework for 

issues beyond the scope of the SDWA requirements for Geologic Sequestration of 

CO2 

In the NODA, the Agency notes: 

EPA recognizes that a more comprehensive framework may be needed and 

that some stakeholders remain uncertain with respect to the potential 

applicability of other Federal environmental statutes such as the Clean 

Air Act, the Resource Conservation and Recovery Act, and the 

Comprehensive Environmental Response, Compensation, and Liability Act to 

various aspects of geologic sequestration of CO2. The Agency is 

currently evaluating the need for a more comprehensive regulatory 

framework to provide legal guidance regarding this emerging technology. 

(74 FR 44805) 

Spectra strongly believes that a more comprehensive framework is needed and 

without one, commercial-scale GS will not become viable in the U.S. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

37
Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28151 

Comment: A. RCRA Applicability Should be Addressed in the Proposed Rule 

In Spectra’s comments on the proposed UIC GS rule we noted a number of 

significant concerns about the potential applicability of Subtitle C 

requirements of RCRA to injection of CO2 from non-exempt processes and 

industries. CO2 re-injection from gas processing is currently exempt from 

Subtitle C requirements of RCRA. Spectra believes that RCRA’s waste regulatory 

regime is completely unnecessary and inappropriate for geologic sequestration of 

CO2. CO2 is not a pollutant, nor a solid waste, nor a hazardous waste. Second, 

CO2 has been properly and safely injected and sequestered for decades in the 

context of enhanced oil recovery (EoR), without the regulatory overlay of 

Subtitle C of RCRA. 

Therefore, Spectra urges EPA to utilize its authority under Subtitle C of RCRA 

to exempt CO2 from RCRA under its contingent management approach. Under this 

approach EPA may take into consideration the relative risks posed by different 

wastes (i.e., some wastes are by nature more toxic than others), the capacity 

for a waste to breakdown and thus become less toxic in the environment (i.e., 

some wastes degrade faster than others), how long it takes a waste to degrade, 

and the potential for human exposure and accumulation in tissue. The application 

of these criteria to CO2 weigh in the favor of exempting CO2 injection and 

disposal from hazardous waste regulations. 

Given the minimal risks from properly managed CO2 pursuant to SDWA’s authority, 

EPA should exempt CO2 streams entirely from RCRA hazardous waste regulations or, 

alternatively, establish a "safe harbor" for the injection of CO2, including 

impurities, by clarifying minimum performance standards or testing requirements. 

Due to the nature of the emissions captured, the injectate may include 

38
significant levels of impurities. The concept of a blanket exemption is fully 

consistent with the Agency’s "contingent management' approach under RCRA, 

whereby certain low-risk wastes are exempted entirely from RCRA Subtitle C 

regulations. See EPA’s Contingent Management Technical Background Document, 

October 29, 1999. 

Further argument for a RCRA exemption, and consistent with the concept of 

contingent management, is the fact that Congress exempted certain wastes from 

regulation under Subtitle C of RCRA. In 1980, when Congress amended the Solid 

Waste Management Act, it opted to temporarily exempt certain high-volume low 

toxicity wastes from the Subtitle C hazardous waste regulatory scheme, 

including, among others, "fly ash waste, bottom ash waste, slag waste and flue 

gas emission control waste generated primarily from the combustion of coal or 

other fossil fuels" (hereafter referred to as "FFC' wastes) 42 U.S.C. § 6921(b) 

(3)(A)(i). 

EPA ultimately made the determination that more stringent regulations were not 

necessary or desirable. Based on a plain language reading of the Bevill 

Amendment, it appears that CO2 falls within the scope of the exemption as a flue 

gas emission control waste. Similar to FFC wastes, CO2 are a high-volume low 

toxicity waste when properly managed in underground formations. Therefore, we 

believe the Bevill Amendment presents the Agency with another viable option for 

exempting CO2 from Subtitle C. 

B. EPA Must Minimize the Liability Regime under CERCLA for GS to the Fullest 

Extent of Its Authority 

The potential application of the sweeping liability regime under the 

Comprehensive, Environmental Response, Compensation, and Liability Act of 1980 

("CERCLA") will have an absolute chilling effect on the underground injection of 

CO2. The threat of CERCLA litigation and the potential liability to a GS owner 

or operator is alone significant and could seriously discourage the siting and 

construction of a GS operation. Under CERCLA’s strict liability regime, an owner 

or operator may be held jointly and severally liable for response costs related 

to any release or potential release of a hazardous substance from a facility. In 

addition to federal and state enforcement actions, CERCLA also authorizes 

private parties to seek remediation costs from an owner/operator who is alleged 

to have caused an actionable release under CERCLA. 

Therefore, given the extensive size of the CO2 plume, covering tens of square 

miles, a private landowner within the AoR and whose property is situated above 

39
the CO2 plume could potentially assert a CERCLA claim against an owner/operator 

of a GS operation. Consequently, we believe the Agency must seek to establish a 

"safe harbor" for those engaged in GS operations. Such safe harbor must include 

the CO2 and any impurities by clarifying minimum performance standards, employed 

technologies, or testing requirements, which if used, will exempt subsurface 

releases from CERCLA liability. 

EPA has the authority and discretion to interpret and further clarify the scope 

and extent of the "federally permitted release" exemption to GS injection. The 

language used for the UIC Exemption does not specifically limit the exemption to 

compliance with or the terms identified in an enforceable permit; rather, the 

UIC Exemption uses a much broader phrase "authorized under." Under the plain 

language of this UIC Exemption, the Agency has the authority to define more 

broadly (whether pursuant to a permit or outside the context of a permit) what 

fluids and releases are authorized by either the federal or state UIC program. 

It is unambiguous from the plain text of the statute that Congress intended that 

releases authorized under the SDWA UIC program not be subject to CERCLA 

liability. It is also clear that the Agency has broad authority to clarify what 

releases should be covered under the GS Rule. Therefore, the Agency need not 

wait for the issuance of permits to decide on a case-by-case basis what is an 

appropriate or inappropriate release. EPA should make clear that all fluids 

injected pursuant to an authorized program or an approved permit will not give 

rise to CERCLA liability where the release occurs in and effects only subsurface 

formations and is geologically contained. 

Individual Response: Regarding RCRA, the final GS rule requires owners or operators to 

characterize their CO2 stream as part of their permit application process to determine whether the 

injectate is a RCRA hazardous waste. If the CO2 stream is determined to be a hazardous waste, 

injection may only occur in a Class I hazardous waste injection well. Additionally, EPA clarifies that a 

determination as to whether the presence of hazardous substances in CO2 results in CERCLA liability 

from a sequestration facility depends entirely on the composition of the specific CO2 stream and the 

environmental media in which it is stored (e.g., soil or ground water). 

For additional information, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-OCT-10 

Notes: 

40
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28297 

Comment: II. EPA Should Establish a More Comprehensive Regulatory Framework. 

In the NODA, EPA stated that it had "received a number of comments indicating 

that the Agency should further explore environmental and regulatory issues 

beyond the scope of the proposed SDWA requirements for underground injection of 

CO2 for GS [geological sequestration]. EPA recognizes that a more 

comprehensive framework may be needed and that some stakeholders remain 

uncertain with respect to the potential applicability of other Federal 

environmental statutes such as the Clean Air Act, the Resource Conservation and 

Recovery Act, and the Comprehensive Environmental Response, Compensation, and 

Liability Act to various aspects of geologic sequestration of CO2. The Agency is 

currently evaluating the need for a more comprehensive regulatory framework to 

provide legal guidance regarding this emerging technology." 74 Fed. Reg. 44,805. 

The Sierra Club strongly reiterates the point raised in its December comments 

that it is critical that the agency develop a comprehensive regulatory structure 

for CCS. Given the myriad of risks associated with CCS, Sierra Club believes 

that the Safe Drinking Water Act is not of sufficient scope and enforceability 

to handle a regulatory field as broad as CCS. Specifically, the Safe Drinking 

Water Act only protects "underground sources of drinking of water" and any CCS 

program raises many potential issues other than groundwater impacts. 

EPA acknowledges in the rule: 

[t]he SDWA does not provide authority to develop regulations for all 

areas related to GS. These areas include, but are not limited to, 

capture and transport of CO2; determining property rights (i.e., to 

permit its use for GS and for possible storage credits); transfer of 

liability from one entity to another; and accounting or certification 

for greenhouse gas (GHG) reductions. 

73 Fed. Reg. 43,492, 43,495 (July 25, 2008). 

Sierra Club cannot emphasize strongly enough the absolute need that the 

government regulates CCS in a comprehensive and inclusive manner that accounts 

for all potential environmental and health impacts, and the universe of issues 

involved with large-scale CCS implementation such as capture, transportation and 

41
pipeline standards, interstate boundary issues, and liability. Moreover, it is 

simply not possible for the government to adequately regulate such a complex 

process through piecemeal regulations. A comprehensive regime, as opposed to a 

patchwork of regulations under different statutes, would be more adaptive to 

emergent information on this budding program as it becomes available. 

Moreover, the Agency should clarify that the rule should specify that an 

intrusion into a USDW is not a "federally permitted release" under CERCLA. EPA 

notes in the preamble to the proposed rule, 73 Fed. Reg. 43,504, that CERCLA 

exempts from liability certain "federally permitted releases, including releases 

in compliance in a UIC permit under the Safe Drinking Water Act." EPA further 

notes that "Class VI requirements and permits will need to be carefully 

structured to ensure that they do not ‘authorize’ inappropriate hazardous 

releases." EPA should go further and effectively prohibit Class VI permit 

conditions that would make the "federally permitted release" defense available 

should injected fluids or displaced formation fluids enter or endanger USDWs. 

This prohibition should be added to Subpart E - Permit Conditions, or to any 

other appropriate section of the rule. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; 

Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

Regarding CERCLA, EPA clarifies that a determination as to whether the presence of hazardous 

substances in CO2 results in CERCLA liability from a sequestration facility depends entirely on the 

composition of the specific CO2 stream and the environmental media in which it is stored (e.g., soil or 

ground water). For additional information, see the preamble to the final rule and the responses to 

comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

42
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28317 

Comment: In terms of the regulatory framework for geologic storage, many commenters on 

the proposed rules favor a more comprehensive framework for geologic storage 

which would address issues under statutes other than the Safe Drinking Water Act 

such as the Clean Air Act, RCRA and CERCLA. EPA should adhere to its limited 

jurisdiction under the Safe Drinking Water Act to achieve a stable regulatory 

framework and to avoid challenges based on the lack of legal authority. The 

Agency should also work to develop a single rule to address issues arising 

outside the context of the Safe Drinking Water Act to avoid a patchwork 

regulatory scheme for carbon capture and storage. 

EPA is considering various positions directly impacting carbon capture and 

storage projects under its proposed rule on mandatory reporting of greenhouse 

gases and proposed changes to the renewable fuel standard program. This approach 

increases the risk of a patchwork approach to regulation relative to state 

involvement in the administration of the carbon capture and storage regulations. 

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the 

need for regulatory clarity to ensure that USDWs are protected from endangerment. In developing the 

final GS rule, the Office of Water coordinated with other Agency program offices and across federal 

agencies (e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean 

Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; and 

the Bureau of Land Management). The Agency continues to evaluate areas of potential applicability of 

other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource 

Conservation and Recovery Act; the Comprehensive Environmental Response, Compensation, and 

Liability Act; and the Marine Protection, Research, and Sanctuaries Act to various aspects of GS and 

CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy 

and maximize efficiencies for owners or operators. For additional information, please see the 

discussion entitled "How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS 

Activities?" in the preamble to the final GS rule. 

EPA Team Member: 

43
Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2000 2. Comments on Research, Data Analysis, and Findings presented in the 

NODA (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27864 

Comment: 3. EPA requests comments on parts of the FR proposed rule 

b. IPCC.2005. IPCC Special Report on Carbon Dioxide Capture and Storage. 

Prepared by Working Group III of the Intergovernmental Panel on Climate Change. 

Metz, B. O. Davidson, H.C. de Conininck, M. Loos, and L.A. Meyer (eds.). New 

Yourk: Cambridge University Press. Kobelski, B.J., R.E. Smith, and A.L. 

Whitehurst. 2005. 

This report was summarized by IPCC. As with all IPCC summary reports 

IPCC, 2005 is a discussion report of CO2 in broad generalities. The word "well" 

meaning an injection well is used once in the report and refers to the well 

leaking. This is not a report dealing with Class VI wells. 

Individual Response: EPA agrees that the IPCC report is a general report, but considers it to be an 

extensive compilation of expert research that is relevant to the Agency's rulemaking. EPA adds that 

44
Chapter 5 of the report discusses many of the technical issues related to siting, constructing, and 

monitoring GS wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: This comment contains text from two non-consecutive parts of the letter, line 109 and lines 

120-129. The comment (and its associated response) appears twice in this report, once for each set of 

line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Emily Rochon 

Commenter Organization: Greenpeace International 

EPA Letter ID: 0342 

EPA Comment ID: 28636 

Comment: GS studies highlight the significant knowledge gaps associated with CO2 storage 

The geological studies that are highlighted in the NODA provide interesting new 

information while underscoring how much more work needs to be done in order to 

fully understand that which the EPA is seeking to regulate. And while modeled 

analyses and calculations provide helpful insights they are imperfect proxies 

for real world experience. 

Individual Response: EPA acknowledges that research continues on GS, but believes that sufficient 

data exist on which to base final requirements for GS at this time. EPA continues to work with DOE, 

national laboratories (such as Lawrence Berkeley National Laboratories), the USGS, and internal 

Agency Offices (e.g., Office of Research and Development) on research on various aspects of GS, 

including potential risks to USDWs. 

EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

45
Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27882 

Comment: The NODA also notes that the availability of recent field data and research 

studies "could change EPA's approach to the final rulemaking." 73 Fed. Reg. at 

43492,44803. The NODA contains discussion on three experimental GS projects. In 

evaluating the techniques employed in these projects and the data produced, the 

Agency should keep in mind that experimental projects are just that-experimental 

projects. The techniques employed in any given setting may have been intended to 

provide information about that specific technology or that particular setting, 

but their successful employment in an experimental setting should not dictate 

their universal application. 

Individual Response: EPA believes that the regional partnerships provide important information on 

GS, but recognizes that use of a technology in a RCSP project does not necessarily make the 

technology valid for all applications. Each project will be unique and the final rule provides for sitespecific approaches to ensure that appropriate construction, operation, and monitoring is performed at 

each site. However, by testing multiple technologies, the pilot sites provide valuable data that 

demonstrate whether or not these technologies are viable and informed the final GS rule. Please see 

the discussion of EPA's final regulatory approach in the preamble to the final GS rule for additional 

detail on the final requirements for GS wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28079 

Comment: EPRI COMMENT#2: The EPA presents a number of research projects in the NODA and 

often concludes with a general statement that the research will be used to 

refine and inform the site characterization, monitoring, and remediation 

requirements and guidance, in the Agency’s final rulemaking. Many of the 

research methods used by the regional partnerships and others were performed 

46
purely for furthering our fundamental understanding and knowledge of GS 

processes and may never evolve beyond the research stage. A cross-well seismic 

survey, which has very limited depth of penetration because of limited source 

strength and therefore requires closely spaced wells, is a good example of a 

research monitoring tool that may never be deployed on a commercial scale. The 

EPA does not provide clarity on how the results will be used or the position or 

direction the Agency has already taken or will take as a result of issues raised 

by the research. EPRI urges EPA to provide this clarity to the regulated 

community before issuing the final rule. 

Individual Response: EPA believes that the regional partnerships provide important information on 

GS, but recognizes that use of a technology in a RCSP project does not necessarily make the 

technology valid for all applications. Each project will be unique and the final rule provides for sitespecific approaches to ensure that appropriate construction, operation, and monitoring is performed at 

each site. However, by testing multiple technologies, the pilot sites provide valuable data that 

demonstrate whether or not these technologies are viable and informed the final GS rule. Please see 

the discussion of EPA's final regulatory approach in the preamble to the final GS rule for additional 

detail on the final requirements for GS wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27934 

Comment: AWWA has reviewed the information provided in the NODA and this additional 

information is not sufficient for us to support the permitting or issuance of 

waivers for large- scale carbon sequestration projects. AWWA recommends that 

permitting of large-scale GS projects be delayed and no waivers allowed until 

information about Department of Energy (DOE) pilot projects and the effects of 

carbon sequestration on the subsurface and USDW can be collected and analyzed. 

We are concerned about the potential for GS projects to result in unintended, 

and possibly harmful, consequences to sources of drinking water. Much of the 

work on GS technology is still in pilot or pre-pilot phase at several magnitudes 

47
of scale smaller than the sort of projects envisioned under this proposal. 

Individual Response: EPA disagrees that the ability to safely deploy CCS on a commercial-scale has 

not been proven or finalizing that the rule should be delayed. EPA is monitoring international GS 

efforts currently operating on a commercial scale. These include the Sleipner Project in the Norwegian 

North Sea (operating since 1996); the Weyburn ER project in Saskatchewan, Canada (since 2000); 

the In Salah Gas Project in Algeria (since 2004); and Snohvit, also in offshore Norway in the Barents 

Sea (since 2008). Other projects EPA is tracking include Gorgon and Otway (in Australia); Ketzin (in 

Germany); Lacq (in France); and CarbFix, (in Iceland). These projects are designed to operate for 

decades and plan to cumulatively inject over 200 MT of CO2. A paper summarizing EPA's research on 

international GS projects and legislation is in the rulemaking docket.

EPA also believes that the DOE pilot projects, while not commercial-scale projects, provide sufficient 

data on all aspects of GS operations (from well construction and injection to long-term plume fate and 

transport and monitoring of containment) to inform the GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27935 

Comment: AWWA recommends that theoretical and observational research be continued and 

that the research must be comprehensive. While the UIC program has a long 

history, the injection of large quantities of CO2 into the ground is a process 

that is not well understood. The substance is different than other UIC compounds 

and the behavior of the compound under severe pressures and temperatures is not 

well known. We strongly recommend that EPA and DOE perform both modeling 

(theoretical) and observational research to better understand the carbon 

sequestration process and the effects of CO2 injection on saline aquifers and 

the subsurface geology. The results of this research must be made available to 

permit writers and stakeholders in a timely manner so that improvements to the 

technology and permitting process can be realized 

48
Individual Response: As described above, EPA disagrees that the ability to safely deploy CCS on a 

commercial-scale has not been proven. In addition to monitoring international commercial scale GS 

efforts, EPA continues to work with DOE, national laboratories (such as Lawrence Berkeley National 

Laboratories), the USGS, and internal Agency Offices (e.g., Office of Research and Development) on 

modeling and field research on various aspects of GS, including potential risks to USDWs. 

EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27953 

Comment: Comment No. 2 

Page 44805 

Issue Topic from EPA's NODA 

EPA is providing this [sic] data and associated project summaries because the 

Agency expects that there may be additional studies and data on other GS 

projects, the use of existing technologies, and GS- related research that may 

inform the Agency's regulatory development process for GS. Such data could 

contribute to the Agency's understanding of site characterization, well 

construction, operation, and monitoring requirements. 

Carbon Sequestration Council Comments 

The state of the science for CO2 storage and the over 35 years of experience 

with CO2 injection for enhanced oil and gas recovery are more than adequate to 

support EPA proceeding with final rule promulgation. 

49
Individual Response: EPA acknowledges the comment and agrees that sufficient data exist on which 

to base final requirements for GS at this time. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27954 

Comment: Comment No. 3 

Page 44805 

Issue Topic from EPA's NODA 

Many commenters suggested that supplementary research on GS is necessary prior 

to rule promulgation and that EPA should wait until the Department of Energy 

(DOE)-sponsored Phase II and Phase III pilot projects are complete before 

finalizing the GS rule. 

Carbon Sequestration Council Comments 

Extensive additional research is proceeding on many different aspects of carbon 

capture, transportation, and sequestration, and the resulting findings will 

certainly add to our current understanding of these aspects. However, there are 

no major technical breakthroughs that need to occur before beginning commercialscale CO2 storage operations in the United States. Moreover, adherence to an 

adaptive approach for regulations will facilitate new information being 

implemented in a responsible way. 

Individual Response: EPA acknowledges the comment and agrees that sufficient data exist on which 

to base final requirements for GS at this time. EPA plans to continue to monitor ongoing research on 

GS, however and intends to use an adaptive approach to the GS regulation. EPA plans, every six 

years, to collect and review data on GS projects to determine whether the appropriate amount and 

types of information and appropriate documentation are being collected, and to determine if 

50
modifications to the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27955 

Comment: Comment No. 4 

Page 44805 

Issue Topic from EPA's NODA 

Comments on the proposal encouraged additional research and investigations on 

areas including (but not limited to): confining zone characterization; modeling; 

CO2 plume movement; geochemistry; impacts of GS on saline formations; leakage 

from abandoned wells caused by material and cement degradation; potential 

pathways for contamination of USDWs; leak mitigation and remediation; and 

criteria for determining that the CO2 plume has stabilized. 

Carbon Sequestration Council Comments 

Furthermore, the oil and gas industry has relevant experience to draw on from 

over 35 years of injecting CO2 for EOR, over 90 years of natural gas storage, 

and 150 years of oil and gas production. The industry also operates large-scale 

CO2 storage projects in offshore Norway, Algeria, and Canada, and has other 

related operations that have proven safe and effective. 

Individual Response: EPA recognizes that industry has decades of experience with injection well 

construction and operation. EPA believes that this experience has led to the development of well 

materials and construction and operating procedures that are applicable to GS wells. 

EPA Team Member: 

Draft Status: 

51
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28135 

Comment: The NODA notes that the availability of recent field data and research studies 

"could change EPA’s approach to the final rulemaking." [Footnote 3] 

Consideration of new data is a perfect example of the adaptive approach EEI 

encouraged in its previous comments, which would allow incorporation of new 

information and data over time, as opposed to the approach favored by some 

commenters of waiting to develop rules until further information and data are 

gathered. In order to spur development of a commercial-scale GS industry, 

potential operators and investors need a regulatory framework within which to 

work now. Information about GS currently available can form the basis of an 

effective and safe program. 

[Footnote 3] 73 Fed. Reg. 43492, 44803. 

The NODA contains discussion of three experimental GS projects as well as 

research being conducted regarding the potential effects on USDWs in the highly 

unlikely event that injected CO2 migrates from the receiving formation. In 

evaluating the techniques employed in these projects and the data produced, the 

Agency should keep in mind that experimental projects are just that - experimental 

projects. The techniques employed in any given setting may have much to offer 

the project, but their successful employment in such a setting should not 

necessarily dictate their universal application. 

Individual Response: EPA believes that the regional partnerships provide important information on 

GS, but recognizes that use of a technology in a RCSP project does not necessarily make the 

technology valid for all applications. Each project will be unique and the final rule provides for sitespecific approaches to ensure that appropriate construction, operation, and monitoring is performed at 

each site. However, by testing multiple technologies, the pilot sites provide valuable data that 

demonstrate whether or not these technologies are viable and informed the final GS rule. Please see 

the discussion of EPA's final regulatory approach in the preamble to the final GS rule for additional 

detail on the final requirements for GS wells.

52
EPA plans to continue to monitor ongoing research on GS, and intends to use an adaptive approach to 

the GS regulation. EPA plans, every six years, to collect and review data on GS projects to determine 

whether the appropriate amount and types of information and appropriate documentation are being 

collected, and to determine if modifications to the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28314 

Comment: The NODA gives an extensive discussion of experimental projects. We would hope 

that EPA is mindful of the fact that experimental projects are just that, 

experimental projects. The successful application of experimental techniques in 

any given setting does not make those techniques appropriate for universal 

application automatically. 

Individual Response: EPA recognizes that use of a technology in a RCSP project does not 

necessarily make the technology valid for all applications. Each project will be unique and the final rule 

provides for site-specific approaches to ensure that appropriate construction, operation, and 

monitoring is performed at each site. However, by testing multiple technologies, the pilot sites provide 

valuable data that demonstrate whether or not these technologies are viable and informed the final GS 

rule. Please see the discussion of EPA's final regulatory approach in the preamble to the final GS rule 

for additional detail on the final requirements for GS wells.

EPA plans to continue to monitor ongoing research on GS, however, and intends to use an adaptive 

approach to the GS regulation. EPA plans, every six years, to collect and review data on GS projects to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

53
**************************************************************************************

**************************************************** 

EPA Comment Code: 2100 2.1 DOE Regional Carbon Sequestration Partnership Projects 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27866 

Comment: 2. EPA tries to use incomplete reports or reports regarding other subjects 

to justify the safety of CO2 geological sequestration. 

EPA refers the reader of the 31 August 2009 Federal Register instant document to 

various reports. When the reader obtains these reports, he/she finds many of 

the projects are in the initial stages of development or are in reality enhanced 

oil or gas recovery projects. The few projects completed injected a small 

quantity of CO2 into the reservoir for a short time, not filling the available 

volume or closing the project under CO2 super critical pressure. Thus, the 

references are replication of what the upstream petroleum industry has been 

doing for more than 20 years. Nothing new regarding CO2 injection wells. 

Admittedly, EPA has fostered new reservoir models and measuring devices, but EPA 

does not provide technical data regarding this work. The reports are written as 

advertising for EPA and the Department of Energy. 

To make sure I was not out of date with my information, I asked Fox, Charles 

[Charles_Fox@kindermorgan.com], VP Kinder Morgan CO2 pipelines. Houston , TX: 

I am commenting on the 31 Aug. 2009 EPA Class VI well request for 

comments. I have read the summaries of the citations provided by EPA 

and DOE. Most of the projects are work in progress or are EOR projects. 

54
Has any reservoir been filled with CO2 and the injection well plugged 

and abandoned, but reservoir pressure is being monitored? I have not 

been able to fine such a project. I request your assistance. 

Response : I don’t know. If you want to find this information I suggest you go 

to the Oil & Gas Journal. 

Thanks, 

Chuck Fox Vice President, Operations and Technology Kinder Morgan CO2 Company, 

L.P. 

The Oil & Gas Journal provide no reference to any completed sequestration 

project. 

Individual Response: EPA acknowledges that the projects listed in the NODA are all in their initial 

stages. In the short time that GS has been a viable technology it would not have been feasible to run 

a project through the closing and post-closure monitoring stages. EPA does believe, however, that the 

projects have provided new and beneficial information. Topics such as site characterization, plume 

monitoring, leak detection, and plume modeling have all been advanced because of these studies. 

EPA believes that the projects highlighted offer new information beyond petroleum industry expertise. 

The Escatawpa, Mississippi site is a deep saline reservoir; the Aneth Field is a combined ER-GS test; 

and the Pump Canyon Site involves injection into deep, unmineable coal seams. EPA has used the 

data generated to inform the final rule. 

EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: This comment contains text from two non-consecutive parts of the letter, lines 63-76 and lines 

88-107. The comment (and its associated response) appears twice in this report, once for each set of 

line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

55
Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27885 

Other EPA Comment Codes and Descriptions: 5450 5.9. Comments on the Proposed Monitoring 

Requirements (146.90) 

Comment: It is appropriate to test techniques such as tracers, surface air/soil gas 

monitoring and microseismic monitoring to determine their overall usefulness and 

effectiveness during this experimental period for CCS. The NODA's description of 

these projects, however, could be read to suggest that the Agency favors 

establishing requirements for the use of tracers, surface air/soil gas 

monitoring, and/or microseismic monitoring. Through EEI, AEP has previously 

advised against imposition of a requirement to use tracers or surface air/soil 

gas monitoring to detect movement of CO2, even where, as the Agency proposed, 

such a requirement is left to the UIC program director's discretion. In the case 

of tracers or surface air/soil gas monitoring, these technologies would likely 

provide too little information, too late, in terms of protecting USDWs, and the 

risk of "false positives" is high. With regards to microseismic monitoring, 

AEP's experience has raised concerns about its application to full-scale 

projects. Specifically, existing monitoring equipment has not proven reliable, 

and alternative sources of comparable equipment are not readily available. 

While the use of many technologies, including tracers, surface air/soil gas 

monitoring and microseismic monitoring may be appropriate and useful in the 

context of an experimental project, the Agency must keep in mind this context. 

The utility of such technologies in any given experimental context does not 

necessarily warrant their use in a commercial setting. Moreover, EPA must 

separate the utility of these technologies in the experimental context in 

further demonstrating the efficacy of storage from their potential utility as 

"leak detectors" during the operation of commercial CCS projects. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. EPA believes that a robust monitoring 

program is critical to ensuring protection of USDWs at GS projects from endangerment, but clarifies 

that the use of any monitoring technique in the pilot projects does not amount to an endorsement by 

EPA or an intent by EPA to require that particular method. By testing multiple technologies, the pilot 

sites provide valuable data that demonstrate whether or not these technologies are viable and inform 

the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

56
site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring, 

and tracers are subject to variability and may not be appropriate or necessary in all settings. EPA also 

recognizes that seismic plume tracking may not be appropriate in all settings, e.g., in certain types of 

geologic formations. The final GS rule at 40 CFR 146.90 gives the Director discretion to determine 

what methods are appropriate. All monitoring must be performed according to the Director-approved 

testing and monitoring plan. See the response to comments document for the proposed rule for 

additional information on EPA’s final approach to monitoring at GS sites.

The testing and monitoring requirements for the GS wells at §146.90 incorporate elements of preexisting UIC requirements for monitoring and testing, tailored and augmented as appropriate for GS 

projects. EPA recognizes that much will be learned about monitoring and testing technologies and 

their application in various settings in the early phases of GS deployment. EPA plans, every six years, 

to collect and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary as part of the Agency’s adaptive rulemaking approach. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James R. Roewer 

Commenter Organization: Utility Solid Waste Activities Group (USWAG) 

EPA Letter ID: 0349 

EPA Comment ID: 28036 

Comment: Finally, as EPA acknowledges in the NODA, the Department of Energy ("DOE") is 

developing and/or operating a number of CO2 GS pilot projects throughout the 

country. These pilot projects share a common purpose: in EPA's own words, to 

"help determine the best approaches for capturing and permanently storing" gases 

such as CO2, as well as to determine "the most suitable technologies, 

regulations, and infrastructure needs for carbon capture, storage, and 

sequestration in different parts of the country." 74 Fed. Reg. At 44805. 

USWAG appreciates EPA's effort to broaden their base of knowledge by drawing on 

the experiences of these pilot projects prior to issuing a final rule. We are 

concerned, however, that this NODA may be premature, as it reflects data from 

57
only a handful of the approximately thirty pilot projects affiliated with DOE. 

For example, the Plains CO2 Reduction Partnership ("PCOR") has only recently 

completed and submitted information regarding their Phase II findings; these 

data, as well as similar data from other pilot projects, are not reflected in 

the NODA. This information will provide valuable insight into the advantages, 

limitations, and challenges associated with CO2 GS in different parts of the 

country. USWAG urges EPA to consider the results of all DOE pilot projects 

prior to drafting a final CO2 GS rule, and to make this information available 

for public review and comment in a subsequent NODA prior to promulgation of a 

final rule. 

Individual Response: EPA acknowledges that the projects listed in the NODA are all in their initial 

stages. In the short time that GS has been a viable technology it would not have been feasible to run 

a project through the closing and monitoring stages. EPA does believe, however, that the projects 

have provided new and beneficial information. Topics such as site characterization, plume monitoring, 

leak detection, and plume modeling have all been advanced because of these studies. 

EPA also believes it is necessary not to delay the regulations as a common nationwide approach is 

needed to oversee this growing activity. Instead, EPA intends to use an adaptive approach to the GS 

regulation. EPA plans, every six years, to collect and review data on GS projects to determine whether 

the appropriate amount and types of information and appropriate documentation are being collected, 

and to determine if modifications to the requirements are appropriate or necessary.

EPA adds that in addition to monitoring the DOE pilot projects, it is also tracking the progress of 

several large international projects, including the Sleipner Field in the North Sea and In Salah, Algeria, 

where millions of tons of CO2 have been injected. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Edward Steadman 

Commenter Organization: Energy & Environmental Research Center (EERC) 

EPA Letter ID: 0352 

EPA Comment ID: 28057 

Comment: The U.S. Environmental Protection Agency (EPA) should be applauded for its 

efforts in "actively tracking the progress" of the RCSP's projects. As the RCSPs 

58
are currently in the process of finalizing the results of their Phase II 

efforts, it is imperative that EPA take into account the substantial body of 

research soon to be released when finalizing its currently proposed rules. The 

availability of such data will contribute greatly to EPA's understanding of site 

characterization, well construction, site operation, and monitoring 

requirements. That being said, EPA should use caution when using the various 

construction, operation, and monitoring techniques utilized throughout the 

duration of these tests as validation for the Class VI requirements as proposed. 

The very purpose of the RCSP Phase II efforts was to examine multiple well 

construction and development techniques as well as numerous monitoring, 

verification, and accounting technologies to find the most effective methods for 

a given site, not to imply that all methodologies applied at all research sites 

are required for the safe and effective geologic storage of CO2 . 

There are additional comments that could be made with regard to the current 

NODA; however, if EPA practices due diligence in reviewing the RCSP data that 

will soon be publicly available, those issues will address themselves. 

Whether EPA extends the deadline of this NODA or decides to issue another NODA, 

it is the belief of the PCOR Partnership that it would be irresponsible to move 

forward with rule promulgation without first reviewing the vast amount of data 

that encompass the breadth of knowledge gained as a result of the RCSP research. 

Individual Response: EPA believes that the regional partnerships provide important information on 

GS, but recognizes that use of a technology in a RCSP project does not make a technology valid for all 

applications. Each project will be unique and the final rule provides for site-specific approaches to 

ensure that appropriate construction, operation, and monitoring is performed at each site. However, 

by testing multiple technologies, the pilot sites provide valuable data that demonstrate whether or not 

these technologies are viable and informed the final GS rule.

EPA intends to continue monitoring these projects for information, but EPA also believes it is 

necessary not to delay the regulations as a common nationwide approach is needed to oversee this 

growing activity. 

EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

59
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28075 

Comment: Finally, as EPA acknowledges in the NODA, the Department of Energy ("DOE") is 

developing and/or operating a number of CO2 GS pilot projects throughout the 

country. These pilot projects share a common purpose: in EPA's own words, to 

"help determine the best approaches for capturing and permanently storing" gases 

such as CO2, as well as to determine "the most suitable technologies, 

regulations, and infrastructure needs for carbon capture, storage, and 

sequestration in different parts of the country." 74 Fed. Reg. at 44805. 

The NODA discusses three experimental GS projects as well as research being 

conducted regarding the potential effects on USDWs in the highly unlikely event 

that injected C02 migrates from the receiving formation. In evaluating the 

techniques employed in these projects and the data produced, the Agency should 

keep in mind that experimental projects are just that-experimental projects. The 

techniques employed in any given setting may have much to offer the project, but 

their successful employment in such a setting should not necessarily dictate 

their universal application. 

Ameren appreciates EPA's effort to broaden their base of knowledge by drawing on 

the experiences of these pilot projects prior to issuing a final rule. We are 

concerned, however, that this NODA may be premature, as it reflects data from 

only a handful of the approximately thirty pilot projects affiliated with DOE. 

For example, the Plains CO2 Reduction Partnership ("PCOR")") has only recently 

completed and submitted information regarding their Phase II findings; these 

data, as well as similar data from other pilot projects, are not reflected in 

the NODA. This information will provide valuable insight into the advantages, 

limitations, and challenges associated with C02 OS in different parts of the 

country. Ameren urges EPA to consider the results of all DOE pilot projects 

prior to drafting a final C02 GS rule, and to make this information available 

for public review and comment in a subsequent NODA prior to promulgation of a 

final rule. 

60
Individual Response: EPA believes that the regional partnerships provide important information on 

GS, but recognizes that use of a technology in a RCSP project does not make a technology valid for all 

applications. Each project will be unique and the final rule provides for site-specific approaches to 

ensure that appropriate construction, operation, and monitoring is performed at each site. However, 

by testing multiple technologies, the pilot sites provide valuable data that demonstrate whether or not 

these technologies are viable and informed the final GS rule.

EPA intends to continue monitoring these projects for useful information, but EPA also believes it is 

necessary not to delay the regulations as a common nationwide approach is needed to oversee this 

growing activity. EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six 

years, to collect and review data on GS projects to determine whether the appropriate amount and 

types of information and appropriate documentation are being collected, and to determine if 

modifications to the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28580 

Comment: It should be noted that the NODA seeks comment based on data and finding that 

have been generated by the pilot and demonstration projects conducted by the 

Regional Carbon Sequestration Partnerships. The Partnerships have not conducted 

any pilot or demonstration projects involving sub-seabed sequestration. We are 

concerned about the lack of availability of data that could inform EP A in its 

rulemaking, and would urge the Agency to seek out expert guidance regarding 

specific geological conditions offshore the U.S., as well as expert guidance on 

technical and scientific issues relating to sub-seabed sequestration of CO2. 

Individual Response: EPA acknowledges that none of the RCSP projects currently investigate 

offshore sequestration. The rule for Class VI GS wells is authorized under the Safe Drinking Water Act 

(SDWA). The UIC program does not have purview beyond some boundaries and state territorial 

waters. However, EPA is also monitoring overseas projects such as Sleipner and Snohvit which are 

offshore sequestration facilities. EPA will continue to monitor all sequestration projects, including 

offshore projects for useful information. EPA is also in continual contact with experts in all areas of GS, 

61
including offshore projects. 

EPA has been cooperating with the Bureau of Ocean Energy Management, Regulation, and 

Enforcement (BOEM), formerly the Minerals Management Service, which administers the Outer 

Continental Shelf Lands Act (OCSLA). As a result of recent OCSLA amendments by the Energy Policy 

Act of 2005, the OCSLA provides for the grant of leases, easements, or rights-of-way on the outer 

continental shelf to the extent that an activity “supports production, transportation, or transmission of 

energy from sources other than oil and gas” and complies with the other provisions of OCSLA section 

8(p). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28266 

Comment: b. Summary of Recent Field Data and Research Studies 

The NODA contains discussion of data gathered through three experimental GS 

projects, as well as research regarding the potential impacts of CO2 on USDW 

should CO2 migrate from the receiving formation (which application of the UIC 

rules should prevent) [FOOTNOTE 2]. NACCSA agrees with the Agency that data 

gathered through experimental projects and research may properly be used to 

shape the course of GS regulation. 

FOOTNOTE 2: It is notable that even assuming that the UIC rules would fail to 

protect against impacts to USDW, the majority of results showed USDW within 

acceptable drinking water standards. 

NACCSA further submits that in evaluating the techniques employed in these 

projects and the data gathered from them, the Agency should retain the context 

in mind. The NODA's discussion of the three regional partnership projects, for 

example, emphasizes their use of tracers and/or surface air/soil gas monitoring 

to detect CO2 movement (or lack thereof). While testing of these technologies is 

undoubtedly beneficial, the NODA's language seems to imply that the Agency 

favors employing requirements for their use in Class VI projects. The proposed 

regulations likewise proposed granting discretion to the program director to 

62
require the use of tracers and/or surface air/soil gas monitoring. As detailed 

in NACCSA's prior comments, this proposal is problematic for several reasons, 

even where discretion is retained in the program director. While the use of many 

technologies, including tracers and surface air/soil gas monitoring, may be 

appropriate and useful in the context of an experimental project, such use does 

not militate in favor of a requirement to use the technologies in a commercial 

context. NACCSA encourages the Agency to give full consideration to the numerous 

other provisions proposed for the protection of USDW. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

and tracers are subject to variability and may not be appropriate or necessary in all settings. The GS 

rule at 146.90 gives the Director discretion to determine what methods are appropriate. All monitoring 

must be performed according to the Director-approved testing and monitoring plan. See the response 

to comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27907 

63
Comment: DOE-Sponsored Regional Carbon Sequestration Partnership Projects (III.B.) 

DEQ supports the pilot project approach that EPA has taken in partnership with 

the Department of Energy. A thorough site characterization is the most 

important requirement for most geologic sequestration projects. DEQ also 

supports the testing and research of analytical models to ensure protection of 

drinking water resources. 

Individual Response: EPA agrees that the pilot project approach will greatly enhance the knowledge 

of site characterization and modeling needed for proper design and operation of GS projects. 

Data and information collected during site characterization also informs the development of 

construction and operating plans, provides inputs for AoR delineation models, and establishes baseline 

information to which geochemical, geophysical, and hydrogeologic site monitoring data collected over 

the life of the injection project can be compared. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28169 

Comment: C. Research, Data Analysis and Findings 

We agree with EPA that the Agency should continue to make available the results 

of studies and data coming out of the Department of Energy (DOE) Regional Carbon 

Sequestration Partnerships, and other research efforts, and that this data can 

inform the Agency’s rulemaking effort now, and going forward. The Safe Drinking 

Water Act as it applies to the proposed Class VI expressly mandates the 

incorporation of any amendments to the federal regulations into state programs. 

This process will allow the results of future study (including this research) to 

be incorporated into state Class VI programs over time. [FOOTNOTE 7] Such an 

adaptive approach to regulating means the results of this research can be 

incorporated in a revised regulatory framework. This consideration, combined 

with the abundant scientific evidence already considered by EPA in the 

64
development of this proposal, means that EPA need not wait for the completion of 

the DOE program before finalizing this rule. 

FOOTNOTE 7 - 42 U.S.C. §300h(b)(1)(B). 

We provide below specific thoughts about research results and progress described 

by the Agency in the NODA. 

Individual Response: EPA agrees that the monitoring and publication of results of the RCSP projects 

in combination with an adaptive approach to the rule is the best way to ensure protection of USDWs 

while keeping up with ongoing research developments. EPA believes that the projects have provided 

new and beneficial information. The state of knowledge regarding site characterization, plume 

monitoring, leak detection, and plume modeling have all been advanced because of these studies; as 

such they have informed the GS rule development. 

EPA is using an adaptive approach to regulating CO2 injection for GS. EPA plans, every six years, to 

collect and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28139 

Other EPA Comment Codes and Descriptions: 5450 5.9. Comments on the Proposed Monitoring 

Requirements (146.90) 

Comment: It is appropriate to test techniques such as tracers and surface air/soil gas 

monitoring to determine their overall usefulness and effectiveness during this 

experimental period for CCS. The NODA’s description of these three projects, 

however, could be read to suggest that the Agency favors employing requirements 

for the use of tracers and/or surface air/soil gas monitoring. EEI has 

previously advised against imposition of a requirement to use tracers or surface 

air/soil gas monitoring to detect movement of CO2, even where, as the Agency 

65
proposed, such a requirement is left to the UIC program director’s discretion. 

In brief, these technologies would likely provide too little information, too 

late, in terms of protecting USDWs, and the risk of "false positives" is high. 

Requiring their use may create or encourage overly negative and unwarranted 

public perception regarding the safety of GS. Further, tracers may present 

their own safety concerns. Finally, the Agency’s authority under the SDWA to 

protect USDWs via these surface-level monitoring tools is not clear. 

While the use of many technologies, including tracers and surface air/soil gas 

monitoring, may be appropriate and useful in the context of an experimental 

project, the Agency must keep in mind this context. The utility of such 

technologies in any given experimental context does not necessarily warrant in 

favor of requiring their use in a commercial setting. Moreover, EPA must 

separate the utility of these technologies in the experimental context in 

further demonstrating the efficacy of storage from their potential utility as 

"leak detectors" during the operation of actual commercial CCS projects. As 

noted above, tracers will not provide sufficient information in an appropriate 

timeframe to allow for immediate remediation of any deficiencies in the 

injection well that may result in a CO2 leak. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

and tracers are subject to variability and may not be appropriate or necessary in all settings. The GS 

rule at 146.90 gives the Director discretion to determine what methods are appropriate. All monitoring 

must be performed according to the Director-approved testing and monitoring plan. See the response 

to comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

66
Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28145 

Other EPA Comment Codes and Descriptions: 5700 5.14. Comments on Other Aspects of the 

Proposed Rule 

Comment: B. Significant work is still ongoing at the pilot stage for GS 

As a member of the Plains CO2 Reduction (PCOR) Partnership and the sponsor of a 

Phase III pilot project, Spectra Energy is actively involved in the development 

of new data from pilot efforts in GS. As EPA notes in the NOPR, 

EPA received comments from stakeholders requesting that additional data 

be made available to the public before a final rulemaking (particularly 

related to specific areas of GS) and indicating that more research is 

needed to support GS in general. Many commenters suggested that 

supplementary research on GS is necessary prior to rule promulgation and 

that EPA should wait until the Department of Energy (DOE)-sponsored 

Phase II and Phase III pilot projects are complete before finalizing the 

GS rule. Others believed that a final rulemaking should proceed and that 

new information and data from ongoing GS research should be considered 

and incorporated over time as part of an adaptive rulemaking process. 

(74 FR 44805) 

In accordance with such, we note that EPA acknowledged that it received many 

comments suggesting that promulgation of this rule should be postponed until the 

DOE-sponsored Phase II and Phase III projects are complete. It is Spectra’s 

understanding that the summaries for Phase II projects are due to the DOE by 

December 31, 2009. The actual data and results from these Phase II projects 

could provide significant value as EPA proceeds with development of this Rule. 

As such, given the short timeframe, Spectra recommends that EPA postpone final 

promulgation of the GS Rule until it has reviewed those Phase II reports. 

67
Individual Response: The Phase II RCSP projects are due to be completed soon and EPA plans to 

monitor those projects and others. However, EPA does not plan on delaying implementation of the rule 

in order to obtain results of these or other studies. EPA is implementing an adaptive approach to the 

rule in order to best incorporate ongoing research while still affording protection to USDWs from 

endangerment on a nationally consistent and early basis. EPA plans, every six years, to collect and 

review data on GS projects to determine whether the appropriate amount and types of information 

and appropriate documentation are being collected, and to determine if modifications to the 

requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2110 2.1.1. SECARB (Escatawpa, MS) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28037 

Comment: Class VI well construction, operational, and monitoring requirements 

EPA has noted in the NODA that the SECARB project "employs, demonstrates, and 

validates the EPA's proposed Class VI well construction, operational, and 

monitoring requirements" (NODA, p. 44806). However API notes that the well 

involved in this project is permitted as a Class V well and largely meets Class 

I design standards. API continues to urge EPA to reconsider its proposed well 

construction and operation requirements, which while protective, are more 

prescriptive than necessary for commercial- scale implementation of CCS and do 

not reflect industry's 35-plus years of success in injecting CO2 under the Class 

68
II UIC program. [Footnote 1] The Class II EOR wells constructed for these CO2 

injection projects - and their operating practices - have an excellent record of 

mechanical integrity and of protecting USDWs. Some of EPA's proposed 

requirements are not only unnecessarily burdensome, but might also interfere 

with operations and could introduce unintended risks. For example, cementing 

the longstring casing to surface is not always possible and prevents the 

annulus from serving many of the same functions that a monitoring well might. 

The results of the SECARB project do not imply that regulations more similar to 

Class II regulations would not have worked equally well. 

[Footnote 1] For a complete discussion of API's concerns with the proposed well 

construction and operating requirements, please see API's December 2008 comments 

on EPA's Proposed Class VI rules. 

Individual Response: EPA recognizes that the oil and gas industry has experience injecting CO2 and 

that many of the wells used for ER may be suitable for GS; however, GS is sufficiently different from 

Class II ER operations to warrant the tailored construction requirements for GS wells at §146.86. For 

example, the volume of CO2 anticipated to be injected in Class VI wells is significantly greater than for 

Class II wells. Reservoir pressure conditions will be different, with Class VI injection operations 

involving large volumes of CO2 and likely having higher pressures within their storage formations than 

Class II ER projects. The Class VI regulations also address the unique physical characteristics of CO2 

including its buoyancy and potential corrosivity. See the response to comments document for the 

proposed rule for additional information on EPA’s final approach to construction of GS wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28040 

Other EPA Comment Codes and Descriptions: 2120 2.1.2. SWP (Aneth Field, UT) 

Comment: Soil and air monitoring, used at both the Escatawpa and Aneth Field pilot 

projects, are unlikely to see a positive signal and are therefore unnecessary 

under most foreseeable circumstances. Natural CO2 concentration in soil can 

have high spatial and temporal variation resulting from complex environmental 

69
interactions, particularly in wet, warm environments.[Footnote 4] In the air, 

CO2 has a high detection limit, reducing the benefits of using air monitoring. 

Leakage detection would be particularly difficult in industrial areas or near 

population centers, where CO2 concentration in the air is already high and 

variable. While having knowledge of CO2 flux in the soil and air at a given 

site location may prove useful for site characterization, the utility of soil 

and air monitoring will be highly site specific. The general strategy of 

monitoring programs should be to detect leakage long before it reaches the 

surface. 

[Footnote 4]: Duncker Romanak, K., 1997, Vadose-Zone Geochemistry of Playa 

Wetlands, High Plains, Texas, The University of Texas at Austin, Ph.D. 

dissertation, 273 p., 49 figs. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

are subject to variability and may not be appropriate or necessary in all settings. The GS rule at 

146.90 gives the Director discretion to determine what methods are appropriate. All monitoring must 

be performed according to the Director-approved testing and monitoring plan. See the response to 

comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

70
Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28115 

Comment: 2. While the SECARB study provides an example of one case where the proposed 

constructions standards were followed without apparent incident, this does not 

mean they represent the minimum or exclusive standards necessary to protect 

USDW’s. Other construction standards could prove equally effective. Please 

refer to well construction standards submitted by GWPC in its December 24, 2008 

comments. 

Individual Response: EPA acknowledges that a single project does not prove that a given design is 

effective in all cases or is the only design that would be effective and disagrees that the proposed rule 

requirements are more prescriptive than necessary. The results of the SECARB project, however, do 

show that the proposed requirements are effective in the studied case and can provide for safe 

injection of carbon dioxide that protects USDWs from endangerment. 

EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary.

For more information on the construction requirements for GS wells, see the responses to comments 

on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28094 

Comment: Comments on Research, Data Analysis, and Findings 

Class VI well construction, operational, and monitoring requirements 

71
EPA has noted in the NODA that the SECARB project "employs, demonstrates, and 

validates the EPA’s proposed Class VI well construction, operational, and 

monitoring requirements" (NODA, p. 44806). However, APC notes that no one 

project "validates" a given construction, operation, or monitoring technique in 

a general sense. The well involved in this project, by requirement of the 

Mississippi Department of Environmental Quality, meets Class I hazardous waste 

injection well design standards which were applied in an abundance of caution. 

Construction to these Class IH standards was not proposed voluntarily by the 

SECARB project team. The construction of this well and the resulting 

protectiveness only demonstrate that the design level is sufficient to be 

protective of USDWs not that it is the only design level sufficient to be 

protective. A rich database of successful well construction is also offered by 

the CO2-EOR and underground gas storage experience. APC continues to urge EPA to 

reconsider its proposed well construction and operation requirements which while 

protective, are much more prescriptive and rigorous than necessary for 

commercial-scale implementation of CCS and do not reflect industry’s 35-plus 

years of success in injecting CO2 under the Class II UIC program. The Class II 

EOR wells constructed for these projects - and their operating practices - have 

an excellent record of mechanical integrity and of protecting USDWs. Some of the 

proposed requirements, such as cementing the long string casing to surface, are 

not only unnecessarily burdensome, but might also interfere with operations and 

could introduce unintended risks. 

Individual Response: EPA acknowledges that a single project does not prove that a given design is 

effective in all cases or is the only design that would be effective, and disagrees that the proposed rule 

requirements are more prescriptive than necessary. The results of the SECARB project, however, do 

show that the proposed requirements are effective in the studied case and can provide for safe 

injection of carbon dioxide that protects USDWs. For more information on the construction 

requirements for GS wells, see the responses to comments on the proposed rule in the rulemaking 

docket.

EPA believes that GS is sufficiently different from Class II ER operations to warrant the tailored 

construction requirements for GS wells at §146.86. For example, the volume of CO2 anticipated to be 

injected in Class VI wells is significantly greater than for Class II wells. Reservoir pressure conditions 

will be different, with Class VI injection operations involving large volumes of CO2 and likely having 

higher pressures within their storage formations than Class II ER projects. The Class VI regulations 

also address the unique physical characteristics of CO2 including its buoyancy and potential 

corrosivity. See the response to comments document for the proposed rule for additional information 

on EPA’s final approach to construction of GS wells.

72
EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six years, to collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28658 

Other EPA Comment Codes and Descriptions: 2120 2.1.2. SWP (Aneth Field, UT) 

Comment: Soil and air monitoring, used at both the Escatawpa and Aneth Field pilot 

projects, are unnecessary under most foreseeable circumstances. Natural CO2 

concentration in soil can have high spatial and temporal variation resulting 

from complex environmental interactions, particularly in wet, warm environments. 

In the air, CO2 has a high detection limit; a leak would have to be significant 

and sustained to detect it with air monitoring technologies. Leakage detection 

would be particularly difficult in industrial areas or near population centers, 

where CO2 concentration in the air is already high and variable. Though having 

knowledge of CO2 flux in the soil and air at a given site location may prove 

useful for site characterization, soil and air monitoring will not be effective 

in most places. The general strategy of monitoring programs will be to detect 

leakage long before it reaches the surface, rendering limited utility to these 

techniques. The benefit of these near surface strategies is unlikely to outweigh 

the cost in most situations. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

73
EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

are subject to variability and may not be appropriate or necessary in all settings. The GS rule at 

§146.90 gives the Director discretion to determine what methods are appropriate. All monitoring must 

be performed according to the Director-approved testing and monitoring plan. See the response to 

comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27958 

Comment: Comment No. 8 

Page 44806 

Issue Topic from EPA's NODA 

This SECARB project employs, demonstrates, and validates the EPA's proposed 

Class VI well construction, operational, and monitoring requirements. 

Carbon Sequestration Council Comments 

No one project "validates" a given monitoring technique in a general sense. 

While the well design used in the SECARB project was sufficient for the project, 

a rich database of successful well construction is also offered by the CO2-EOR 

and underground gas storage experience. 

1. The model used in the Escatawpa project was accurate in predicting the 

distance the plume moved, taking into consideration the small scale of the 

74
project, with only 3,027 tons of CO2 injected over 30 days. 2. All monitoring 

activities were concluded in September 2009. No unanticipated migration was 

detected or suspected to have occurred. 3. The purpose of the shallow monitoring 

was to determine if CO2was seeping into shallow geology, groundwater, or 

ecosystems either through geologic pathways or up the well bore. 4. Monitoring 

was performed in the target reservoir with time-lapse VSP and down hole 

geophysical methods and in the near surface with tracers, soil flux, and 

groundwater quality testing. 

Although the injection well for the Escatawpa project was permitted as Class V, 

the Mississippi Department of Environmental Quality (MDEQ) required that the 

more stringent Class I hazardous waste injection well (Class IH) construction 

standards be met. Construction to these Class IH standards was not voluntarily 

proposed by the SECARB project team. EPA should not conclude that these design 

standards are warranted based on this single pilot project experience that did 

not even assess the sufficiency of alternative designs. Instead, EPA should 

adopt less prescriptive standards that are sufficiently protective based on 

industry's more than 35 years of success in injecting CO2 under the Class II UIC 

program. The Class II EOR wells constructed for these projects - and their 

operating practices - have an excellent record of mechanical integrity and of 

protecting USDWs. 

At this point it cannot be concluded that the project components and 

construction design demonstrate and validate EPA's well construction, 

operational, and monitoring requirements. Since this was a research and 

development project some requirements were more stringent and some may have been 

less stringent than would be required for a commercial-scale geologic 

sequestration project. 

The Escatawpa project was essentially an injection test but was very valuable 

from the standpoint of outreach and education, permitting process analysis, and 

site characterization. 

Some of the practices employed at Escatawpa, such as cementing the long string 

casing to surface, may not be possible in all circumstances. The results of the 

SECARB project do not imply that less burdensome regulations would not have 

worked equally well. See the construction recommendations presented in the MSD 

Recommendation Letters of May 14, 2009 and May 15, 2009. 

75
Individual Response: EPA acknowledges that a single project does not prove that a given design is 

effective in all cases or is the only design that would be effective, and disagrees that the proposed rule 

requirements are more prescriptive than necessary. The results of the SECARB project, however, do 

show that the proposed requirements are effective in the studied case and can provide for safe 

injection of carbon dioxide that protects USDWs from endangerment. 

EPA believes that GS is sufficiently different from Class II ER operations to warrant the tailored 

construction requirements for GS wells at §146.86. For example, the volume of CO2 anticipated to be 

injected in Class VI wells is significantly greater than for Class II wells. Reservoir pressure conditions 

will be different, with Class VI injection operations involving large volumes of CO2 and likely having 

higher pressures within their storage formations than Class II ER projects. The Class VI regulations 

also address the unique physical characteristics of CO2 including its buoyancy and potential 

corrosivity. See the response to comments document for the proposed rule for additional information 

on EPA’s final approach to construction of GS wells.

For more information on the construction requirements for GS wells, see the responses to comments 

on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28138 

Comment: 1. Regional Partnership Projects 

In particular, the NODA’s discussion of the SECARB Plant Daniel [Footnote 4] 

project notes that the project meets a number of Class I requirements related to 

pre-injection mechanical integrity of both the injection and monitoring 

well,[Footnote 5] including a radioactive tracer survey. It further emphasizes 

the project’s use of surface or near-surface monitoring for upward 

CO2 migration, stating that use of these techniques "provides the EPA with 

preliminary information regarding the efficacy and appropriateness of these 

technologies at certain sites" and "supports the need for a site-specific 

monitoring plan that will allow use of a range of monitoring techniques suitable 

for each unique GS site." [Footnote 6] It also notes that such monitoring has 

76
found "no indication of the return of the injected CO2 into the shallow 

subsurface." [Footnote 7] The NODA also references the use of tracers in its 

[Footnote 4] EEI member Southern Company is a SECARB partner. Its subsidiary 

Mississippi Power operates Plant Daniel, the host site of the project. 

[Footnote 5] EEI’s December 24, 2008, comments included detailed discussion of 

its concerns about any parallels that might be drawn between Class I hazardous 

waste injection wells and injection wells designed for GS and refers the Agency 

to that discussion. As further discussed herein, the fact that various Class I 

elements may have been employed in any given experimental project should not 

translate to a generalized requirement that those elements be imposed on all 

commercial GS projects. 

[Footnote 6] 74 Fed. Reg. at 44806. 

[Footnote 7] Id. 

Individual Response: EPA acknowledges that a single project does not prove that a given design is 

effective in all cases or is the only design that would be effective, and disagrees that the proposed rule 

requirements are more prescriptive than necessary. The results of the SECARB project, however, do 

show that the proposed requirements are effective in the studied case and can provide for safe 

injection of carbon dioxide that protects USDWs from endangerment. 

For more information on the construction requirements for GS wells, see the responses to comments 

on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from two non-consecutive parts of the letter, lines 314 to 327 and 

lines 333 to 346. The comment (and its associated response) appears twice in this report, once for 

each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

77
EPA Comment ID: 28315 

Other EPA Comment Codes and Descriptions: 2120 2.1.2. SWP (Aneth Field, UT) 

Comment: The NODA emphasizes the use of surface or near surface monitoring for upward 

carbon migration at the SECARB Plant Daniel Project and references the use of 

tracers at the SWP Project in Utah. These technologies would likely provide too 

little information too late in terms of protecting USDWs and they carry a high 

risk of false positive results. Requiring their use may inflame public fears 

regarding the safety of GS projects. EEI advises against the requirement to use 

tracers and/or surface air/soil gas monitoring to detect carbon movement even if 

such requirements are left to the UIC Director's discretion. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

To the comment about the utility of surface or near-surface CO2 monitoring, EPA stresses that 

subsurface geochemical and pressure monitoring is the first line of monitoring that would allow 

detection of potential endangerment to USDWs from GS activities (this is required at all GS sites, as 

described at 146.90). GS projects will not rely solely on surface air or soil gas monitoring for detection 

of such endangerment to USDWs, but such methods may be used to provide additional information on 

the magnitude and location of suspected leaks. 

EPA recognizes that certain monitoring technologies, particularly tracers, are subject to variability and 

may not be appropriate or necessary in all settings. The GS rule at 146.90 gives the Director 

discretion to determine what methods are appropriate. All monitoring must be performed according to 

the Director-approved testing and monitoring plan. See the response to comments document for the 

proposed rule for additional information on EPA’s final approach to monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

78
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28325 

Comment: EPA has noted that, in the NODA, that the SECARB Project "employs, demonstrates 

and validates the EPA's proposed Class VI well construction operational and 

monitoring requirements." However, API notes that the well involved in this 

project is permitted as a Class V well and largely meets Class I design 

standards which were applied in an abundance of caution. API continues to urge 

EPA to reconsider its proposed well construction and operation requirements 

which, while protective, are much more prescriptive and rigorous than necessary 

for commercial scale implementation of CCS and do not reflect the industry's 35 

years of success in injecting CO2 under the Class II UIC Program. 

The Class II EOR wells constructed for these projects and their operating 

practices have an excellent record of mechanical integrity and of protecting 

USDWs. Some of the proposed requirements such as cementing the long string 

casing to surface are not only unnecessarily burdensome, but might also 

interfere with operations including introducing unintended risks. The results of 

the SECARB project do not imply that less burdensome regulations would not have 

worked equally well. 

Individual Response: EPA acknowledges that a single project does not prove that a given design is 

effective in all cases or is the only design that would be effective, and disagrees that the proposed rule 

requirements are more prescriptive than necessary. The results of the SECARB project, however, do 

show that the proposed requirements are effective in the studied case and can provide for safe 

injection of carbon dioxide that protects USDWs from endangerment. EPA encourages the use of the 

most protective technologies available, and encourages owners or operators of GS wells to adopt more 

stringent approaches to ensure USDW protection. 

EPA recognizes that the oil and gas industry has experience injecting CO2 and that many of the wells 

used for ER may be suitable for GS; however, GS is sufficiently different from Class II ER operations to 

warrant the tailored construction requirements for GS wells at §146.86. For example, the volume of 

CO2 anticipated to be injected in Class VI wells is significantly greater than for Class II wells. 

Reservoir pressure conditions will be different, with Class VI injection operations involving large 

volumes of CO2 and likely having higher pressures within their storage formations than Class II ER 

projects. The Class VI regulations also address the unique physical characteristics of CO2 including its 

79
buoyancy and potential corrosivity. Refer to the response to comments document on the proposed 

rule for additional information on EPA’s final approach to construction of GS wells.

For more information on the construction requirements for GS wells, see the responses to comments 

on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2120 2.1.2. SWP (Aneth Field, UT) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28192 

Other EPA Comment Codes and Descriptions: 5450 5.9. Comments on the Proposed Monitoring 

Requirements (146.90) 

Comment: 6. We support the requirement for project design with a "robust monitoring plan" 

that is capable of corroborating modeling with actual performance. This should 

include assessment of dissolution or dissociation and effects on the 

mobilization of trace elements. 

Individual Response: EPA agrees that GS project design requires a robust monitoring plan. An 

essential part of that monitoring plan must be obtaining data to validate computational model 

performance. The GS rule includes requirements at 146.90(d) for ground water monitoring for 

geochemical changes, which can be used to detect mobilization of metals and dissolution of CO2 in 

subsurface brine. See the response to comments document for the proposed rule for additional 

80
information on EPA’s final approach to monitoring for GS projects. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28040 

Other EPA Comment Codes and Descriptions: 2110 2.1.1. SECARB (Escatawpa, MS) 

Comment: Soil and air monitoring, used at both the Escatawpa and Aneth Field pilot 

projects, are unlikely to see a positive signal and are therefore unnecessary 

under most foreseeable circumstances. Natural CO2 concentration in soil can 

have high spatial and temporal variation resulting from complex environmental 

interactions, particularly in wet, warm environments.[Footnote 4] In the air, 

CO2 has a high detection limit, reducing the benefits of using air monitoring. 

Leakage detection would be particularly difficult in industrial areas or near 

population centers, where CO2 concentration in the air is already high and 

variable. While having knowledge of CO2 flux in the soil and air at a given 

site location may prove useful for site characterization, the utility of soil 

and air monitoring will be highly site specific. The general strategy of 

monitoring programs should be to detect leakage long before it reaches the 

surface. 

[Footnote 4]: Duncker Romanak, K., 1997, Vadose-Zone Geochemistry of Playa 

Wetlands, High Plains, Texas, The University of Texas at Austin, Ph.D. 

dissertation, 273 p., 49 figs. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

81
EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

are subject to variability and may not be appropriate or necessary in all settings. The GS rule at 

146.90 gives the Director discretion to determine what methods are appropriate. All monitoring must 

be performed according to the Director-approved testing and monitoring plan. See the response to 

comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28658 

Other EPA Comment Codes and Descriptions: 2110 2.1.1. SECARB (Escatawpa, MS) 

Comment: Soil and air monitoring, used at both the Escatawpa and Aneth Field pilot 

projects, are unnecessary under most foreseeable circumstances. Natural CO2 

concentration in soil can have high spatial and temporal variation resulting 

from complex environmental interactions, particularly in wet, warm environments. 

In the air, CO2 has a high detection limit; a leak would have to be significant 

and sustained to detect it with air monitoring technologies. Leakage detection 

would be particularly difficult in industrial areas or near population centers, 

where CO2 concentration in the air is already high and variable. Though having 

knowledge of CO2 flux in the soil and air at a given site location may prove 

useful for site characterization, soil and air monitoring will not be effective 

in most places. The general strategy of monitoring programs will be to detect 

leakage long before it reaches the surface, rendering limited utility to these 

techniques. The benefit of these near surface strategies is unlikely to outweigh 

the cost in most situations. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

82
monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

are subject to variability and may not be appropriate or necessary in all settings. The GS rule at 

§146.90 gives the Director discretion to determine what methods are appropriate. All monitoring must 

be performed according to the Director-approved testing and monitoring plan. See the response to 

comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27959 

Comment: Comment No.9 

Page 44806 

Issue Topic from EPA's NODA 

The Aneth Field project confirms the need for a project design with a robust 

monitoring plan, and tests the importance of monitoring and modeling agreement 

in GS projects. 

Carbon Sequestration Council Comments 

Data collected for monitoring will allow for improvement and/or refinement of an 

83
existing model. As the feedback between monitoring and modeling increases 

confidence, the monitoring plan can be adapted as needed (See Cooper, C., ed., 

2009). It is important that the regulations allow for refinements of the 

original monitoring plan, should modeling or reservoir performance results 

indicate operational or monitoring changes are appropriate. 

[Reference]: Cooper, C., ed., 2009, A Technical Basis for Carbon Dioxide Storage: 

New York, Chris Fowler International, CO2 Capture Project, 86p. 

Comment No. 10 

Page 44806 

Issue Topic from EPA's NODA 

In addition, the project demonstrates the utility of various monitoring 

technologies that may be used by owners and operators of Class VI wells. 

Carbon Sequestration Council Comments 

There are many monitoring tools that could be shown to have some utility, but it 

does not follow that every tool - or any particular tool - should be used or 

required for every geological sequestration project, especially as scaling-up 

some of these monitoring techniques from pilot to commercial scale would be 

cost- prohibitive. For example, soil and air monitoring are unnecessary under 

most foreseeable circumstances. The testing of particular monitoring 

technologies does not show the necessity of these techniques or the inadequacy 

of alternatives that were not tested. Soil flux monitoring was not valuable to 

the Aneth project team because background and control point measurements were 

highly variable and data interpretation was difficult. Tracers also did not 

appear to be necessary. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

84
EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

and tracers are subject to variability and may not be appropriate or necessary in all settings. The GS 

rule at 146.90 gives the Director discretion to determine what methods are appropriate. All monitoring 

must be performed according to the Director-approved testing and monitoring plan. See the response 

to comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28137 

Comment: subsurface." [Footnote 7] The NODA also references the use of tracers in its 

discussion of the SWP Project in Aneth Field, Utah, stating that the project 

"confirms the need for a project design with a robust monitoring plan" as well 

as "the utility of various monitoring technologies," and in its discussion of 

the SWP Project in Pump Canyon, New Mexico.[Footnote 8] 

[Footnote 8] Id. at 44806. 

Individual Response: EPA agrees that the RCSP projects confirm the need for a plan for monitoring 

of the injection zone, confining zone(s), USDWs, and other significant geologic settings. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from two non-consecutive parts of the letter, lines 327 to 331 and 

lines 348 to 349. The comment (and its associated response) appears twice in this report, once for 

each set of line numbers. 

85
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28315 

Other EPA Comment Codes and Descriptions: 2110 2.1.1. SECARB (Escatawpa, MS) 

Comment: The NODA emphasizes the use of surface or near surface monitoring for upward 

carbon migration at the SECARB Plant Daniel Project and references the use of 

tracers at the SWP Project in Utah. These technologies would likely provide too 

little information too late in terms of protecting USDWs and they carry a high 

risk of false positive results. Requiring their use may inflame public fears 

regarding the safety of GS projects. EEI advises against the requirement to use 

tracers and/or surface air/soil gas monitoring to detect carbon movement even if 

such requirements are left to the UIC Director's discretion. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

To the comment about the utility of surface or near-surface CO2 monitoring, EPA stresses that 

subsurface geochemical and pressure monitoring is the first line of monitoring that would allow 

detection of potential endangerment to USDWs from GS activities (this is required at all GS sites, as 

described at 146.90). GS projects will not rely solely on surface air or soil gas monitoring for detection 

of such endangerment to USDWs, but such methods may be used to provide additional information on 

the magnitude and location of suspected leaks. 

EPA recognizes that certain monitoring technologies, particularly tracers, are subject to variability and 

may not be appropriate or necessary in all settings. The GS rule at 146.90 gives the Director 

discretion to determine what methods are appropriate. All monitoring must be performed according to 

the Director-approved testing and monitoring plan. See the response to comments document for the 

86
proposed rule for additional information on EPA’s final approach to monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2130 2.1.3. SWP (Pump Canyon, NM) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28039 

Comment: Monitoring 

The development of a monitoring strategy for a given GS project requires the 

consideration of a variety of subsurface factors and location specific concerns. 

Monitoring techniques used in pilot or demonstration projects may not 

necessarily be appropriate for a particular commercial-scale geologic storage 

project, either because of site specific differences or because the cost of 

scaling-up these techniques could be cost-prohibitive. 

The Pump Canyon Project represents just one test of tracers and so its outcome 

should not be generalized beyond its specific circumstances. Use of tracers 

should be a site specific decision. Of more concern, the perfluorocarbon (PFT) 

tracers used in the Escatawpa pilot project are greenhouse gases much more 

potency than CO2. Tracers may be useful for CO2 storage in some circumstances, 

but potential unintended consequences should be considered when deciding whether 

tracers are appropriate, and if so, what kind of tracer is best for the project. 

87
Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, a robust monitoring program is 

critical to ensuring protection of USDWs at GS projects from endangerment, and EPA clarifies that the 

use of any monitoring technique in the pilot projects does not amount to an endorsement by EPA or an 

intent by EPA to require that particular method. By testing multiple technologies, the pilot sites 

provide valuable data that demonstrate whether or not these technologies are viable and informed the 

final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, such as tracers are subject to variability and may 

not be appropriate or necessary in all settings. The GS rule at §146.90 gives the Director discretion to 

determine what methods are appropriate. All monitoring must be performed according to the Directorapproved testing and monitoring plan. See the response to comments document for the proposed rule 

for additional information on EPA’s final approach to monitoring at GS sites.

EPA acknowledges comments regarding the costs associated with monitoring. The Agency believes the 

requirements for comprehensive monitoring are necessary to protect USDWs. A discussion of the costs 

attributed to monitoring technologies (used during injection and the post-injection site care 

timeframes) is available in the Technology and Cost Document for the GS rule, which is in the federal 

docket for this rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28170 

Comment: 1. Regional Partnerships Data 

EPA notes that the DOE Southwestern Regional Partnership site at Pump Canyon, 

near Archuleta, New Mexico, "will inform a determination on whether CO2 can be 

effectively and safely sequestered in coal seams." [FOOTNOTE 8] The results of 

this project are pending and given the quantities injected it is unclear to us 

88
that this particular project will determine the techniques, if any, that might 

establish commercial-scale coal seam GS as a safe and effective option. We 

reiterate our concern expressed in our original comments, that at this time coal 

seams and basalt formations, wherever located, should not be considered 

appropriate formations for GS under Class VI. 

FOOTNOTE 8 - 74 Fed. Reg. 44806. 

Individual Response: EPA acknowledges concerns with ECBM and basalt projects but believes that it 

may be possible to safely utilize these types of formations for GS. The RCSP projects have contributed 

to the state of knowledge about injection into coal seams and basalts for GS, e.g., to determine under 

what conditions such projects can be achieved safely. While the Archuleta project is a small volume 

demonstration, other projects will use larger volumes if this project succeeds. 

EPA does not intend to ban ECBM projects. In the final GS rule, GS into unmineable coal seams will be 

allowed, provided the owner or operator can demonstrate that GS at the site can be performed 

without endangering USDWs. Owners or operators of unmineable coal seam projects will be subject to 

the same site characterization requirements (at §146.82) as those required of other projects. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28095 

Comment: Monitoring: Tracers & Soil and Air Monitoring 

There are many monitoring tools that could be shown to have some utility, but it 

does not follow that every tool - or any particular tool - should be used for 

any given geological storage project, especially as the scaling-up to commercial 

projects would be cost-prohibitive for some of the tested monitoring techniques. 

The testing of particular monitoring technologies does not show the necessity of 

these techniques or the inadequacy of alternatives that were not tested. 

The Pump Canyon Project represents just one test of traces; the outcome should 

89
not be generalized. Use of tracers should be a site specific decision. More 

specifically, the perfluorocarbon (PFT) tracers used in the Escatawpa pilot 

project are of concern, as they are greenhouse gases much more potent than CO2. 

In addition, PFTs have a high-risk of contamination which makes them very 

impractical when utilizing beyond a pilot-scale project. Tracers may be useful 

for CO2 storage in some circumstances, but potential unintended consequences 

should be considered both when selecting whether tracers are an appropriate 

tool, and if so, what kind of tracer is most appropriate for the project. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, a robust monitoring program is 

critical to ensuring protection of USDWs at GS projects from endangerment, and EPA clarifies that the 

use of any monitoring technique in the pilot projects does not amount to an endorsement by EPA or an 

intent by EPA to require that particular method. By testing multiple technologies, the pilot sites 

provide valuable data that demonstrate whether or not these technologies are viable and informed the 

final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, such as tracers are subject to variability and may 

not be appropriate or necessary in all settings. The GS rule at §146.90 gives the Director discretion to 

determine what methods are appropriate. All monitoring must be performed according to the Directorapproved testing and monitoring plan. See the response to comments document for the proposed rule 

for additional information on EPA’s final approach to monitoring at GS sites.

EPA acknowledges comments regarding the costs associated with monitoring. The Agency believes the 

requirements for comprehensive monitoring are necessary to protect USDWs. A discussion of the costs 

attributed to monitoring technologies (used during injection and the post-injection site care 

timeframes) is available in the Technology and Cost Document for the GS rule, which is in the federal 

docket for this rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

90
Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27960 

Comment: Comment No. 11 

Page 44806 

Issue Topic from EPA's NODA 

The Agency sought comment on using unmineable coal seams for GS in the proposed 

rule. The investigation at Pump Canyon will inform a determination on whether 

CO2 can be effectively and safely sequestered in coal seams. 

Carbon Sequestration Council Comments 

Coal bed injection is promising, but it is at a more experimental stage than CO2 

injection into other types of reservoirs. CO2 storage within coal deposits is 

viable but complicated, due to swelling of the coal as methane is displaced by 

CO2, fracturing , and the low permeability of coal matrices. 

We recommend that coal bed injection wells used for GS be left as Class V 

experimental wells at this time. See MSD Recommendation Letter May 14, 2009, 

Item 1. 

Individual Response: EPA acknowledges concerns with ECBM and basalt projects but believes that it 

may be possible to safely utilize these types of formations for GS. The RCSP projects have contributed 

to the state of knowledge about injection into coal seams and basalts for GS, e.g., to determine under 

what conditions such projects can be achieved safely. While the Archuleta project is a small volume, 

other projects will use larger volumes if this project succeeds. 

EPA does not intend to ban ECBM projects. In the final GS rule, GS into unmineable coal seams will be

allowed, provided the owner or operator can demonstrate that GS at the site can be performed 

without endangering USDWs. Owners or operators of unmineable coal seam projects will be subject to 

the same site characterization requirements (at §146.82) as those required of other projects.

The Agency anticipates that in the near-term, most GS in unmineable coal seams will continue to be 

experimental. Such projects may be permitted as Class V experimental technology wells if they are of 

an experimental nature (i.e., to test GS technologies and collect data). 

EPA Team Member: 

91
Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2200 2.2. LBNL Studies 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28206 

Comment: The Discussion of the Modeling 

Conducted by LBNL Lacks Critical Context Needed for these Results to Be Directly 

Relevant to the Proposed Class VI CO2 Storage Rule. "Section III. Research, Data 

Analysis, and Findings. C. Lawrence Berkeley National Laboratory (LBNL) Studies" 

of the NODA is devoted to summarizing key findings of state-of-the-art research 

underway at LBNL (pp. 44807-44804). While much of the substance of the research 

described here is important and germane to the NODA, the way in which key 

aspects of this research is presented is problematic and does not further the 

USEPA’s goal of communicating to potential CCS stakeholders that the USEPA is 

committed to crafting a proposed Class VI rule that will allow it to fulfill its 

responsibilities under SDWA and other statues and that is built upon a solid 

foundation of the best available scientific and engineering research. 

Individual Response: EPA believes it accurately explained the results of the LBNL studies and notes 

that the studies themselves were available to stakeholders through the docket for the GS rule and 

NODA. EPA believes that the studies presented, along with all other research presented as background 

for the GS rulemaking, support its position that the GS rule is based on a solid UIC regulatory 

92
framework, with requirements that are tailored to the unique aspects of GS of CO2. The Agency plans 

to use an adaptive approach to ensure that USDWs are protected from endangerment while making it 

possible to meet the potentially fast pace of GS deployment. EPA believes that an adaptive approach 

will allow regulatory development to proceed in time to meet the current and future demand for Class 

VI permits while recognizing the need to: continue to gather data from pilot projects and other 

research as it becomes available; and to enhance understanding of the technical and administrative 

aspects of GS deployment, operation, and technology developments. EPA plans, every six years, to 

collect and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27908 

Comment: Lawrence Berkeley National Laboratory (LBNL) Studies (III.C.) 

The LBNL is currently evaluating potential effects of CO2 injection on ground 

water and surrounding formations, including a case study in a sedimentary basin. 

We have concern that this study does not address other types of basins which may 

be proposed for geologic sequestration in Oregon. DEQ recommends that 

additional studies be pursued in different basin scenarios on mobilization of 

constituents and likelihood or frequency of leakage risks. 

Individual Response: EPA continues to monitor the progress of research on the feasibility of various 

types of geologic formations. For example, DOE's RCSPs are conducting numerous pilot projects that 

inject CO2 into a variety of formation types, including saline, basalt, coal seams, and oil and gas 

reservoirs. EPA is using an adaptive approach to regulate GS injection. EPA will collect and review 

project data on early GS projects, including those that inject into formations such as coal seams and 

basalts, to determine whether the appropriate amount and types of information and documentation 

are required and being collected. EPA plans, every six years, to collect and review data on GS projects 

to determine whether the appropriate amount and types of information and appropriate 

documentation are being collected, and to determine if modifications to the requirements are 

93
appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27945 

Comment: In summary, both the LBNL studies on groundwater quality changes and basin-scale 

hydrologic impacts suggest that additional research is needed to better 

understand the potential effects on USDWs. More research, including experimental 

work with actual groundwater above potential GS sites, is needed to ensure that 

arsenic, lead, and other constituents are not released as the result of the 

final GS rule. The section on lead needs to be re-evaluated based on the MCLG 

not on the Action Levels. The use of MCLs as the basis for a policy of 

permissible degradation needs to be reexamined. Additionally, AWWA suggests 

that EPA conduct a peer review of the LBNL reports and the modeling approach 

using the Science Advisory Board Drinking Water Committee or the National 

Academy of Science as the review panel. AWWA also supports the requirement that 

basin-scale hydrologic impacts of CO2 storage on reservoir pressure and farfield pressures be addressed in the GS permitting process. 

Individual Response: EPA clarifies that the GS rule does not specifically require owners or operators 

to address basin-scale hydrologic impacts of CO2 storage on reservoir pressure and far-field 

pressures. However, EPA agrees that proactive management of basin scale concerns to maintain 

pressures within acceptable ranges is important, and encourages owners or operators and permitting 

authorities to communicate planned GS activities to maximize coordination and minimize pressure 

interference. If a permit applicant (or the permitting authority) is aware of pending GS projects near a 

proposed well, the AoR delineation performed pursuant to §146.84 should account for the impacts of 

multiple owners and operators injecting within a single basin. EPA anticipates that, where multiple 

operators are involved, the Director would not approve modeling that does not account for changes 

that may result from all injection operations. As the commenter points out, the proximity of injection 

sites to each other and the relative timing of each injection operation might indicate a possible 

increase in risk for the containment of the total CO2 and/or the effects of hydraulic perturbations and 

brine displacement.

94
EPA continues to fund research the effect of GS on USDWs. In December 2009, EPA awarded a STAR 

grant to Clemson University to investigate the potential for GS to affect USDWs. The research will 

involve laboratory experiments and modeling simulations to investigate the fate of dissolved CO2 in 

underground geologic formations and to determine possible risks associated with the dissolution of 

CO2 in underground aquifers. Other projects funded by the STAR grants include the following: the 

University of Illinois-Urbana will conduct research related to reducing hydrologic and geochemical 

uncertainties associated with CO2 sequestration in deep, saline reservoirs; the University of Texas at 

Austin will assess appropriate monitoring approaches at geologic sequestration sites; the University of 

Utah will integrate design, monitoring, and modeling of GS to assist in developing a practical 

methodology for characterizing risks to USDWs; Columbia University will conduct laboratory 

experiments on shallow aquifer systems to improve our understanding of geochemical and 

microbiological reactions under low ph/high CO2 stress; and Princeton University will develop a set of 

computational tools to model CO2 and brine movement associated with GS.

EPA notes that changing the criteria, such as maximum contaminant levels, used by the UIC program 

to determine whether a USDW is endangered is outside the scope of this rulemaking. 

EPA also clarifies that it does not have the authority to ask the Science Advisory Board or the National 

Academy of Sciences to review the LBNL studies because the studies were not performed by EPA but 

by LBNL, a branch of the Department of Energy. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-JUL-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2210 2.2.1. Groundwater Quality and Mobilization of Trace Elements (seeking 

comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

95
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28193 

Comment: 7. We note that a LBNL study, referenced in the NODA, made an assumption in a 

release scenario that "leakage into a shallow aquifer would occur at a constant 

rate over a 100 year period". Constant rate leakage is not logical, especially 

over such a long time period -> pressures (driving force) will decline, and 

mineralization will occur, to list two factors against constant rate leakage. 

The assumption is not even valid as a "worst case scenario". 

8. While the LBNL work is appreciated, USEPA should view it as a 

"generalization" and still allow "local studies in local conditions". 

Specifically, assessment of leakage risk needs to be in context of local 

conditions. 

Individual Response: EPA agrees that the LBNL study is a generalization with the objective to better 

understand, in a global sense, the vulnerability of representative and relevant aquifer types in the 

case of CO2 intrusion, in order to provide sound scientific information as a basis for further studies on 

groundwater quality concerns. The study was not meant to be site specific; rather the authors suggest 

the work should be followed by site-specific investigations, such as in situ experiments with associated 

modeling. Furthermore, the LBNL study focused on the potential consequences of CO2 leakage into 

USDWs, without assessment of the probability for leakage. It is understood (and mentioned in the 

NODA) that the risk of CO2 leaking from deep storage is low for properly managed GS projects. 

However, the potential conse¬quences of unlikely leakage events need to be understood and 

predictive capabilities need to be developed as a basis for risk and vulnerability assessment. 

As to the leakage case chosen for the LBNL modeling study, EPA notes that even a comprehensive 

sensitivity study cannot encompass all possible aquifer conditions and release scenarios. The 100-year 

time period selected in the LBNL study is reasonable, assuming that the leak remains undetected. The 

time period was chosen to be able to evaluate both the short-term and the long-term geochemical 

consequences of leakage. 

EPA agrees over-pressures necessary to inject CO2 into a storage reservoir will decline following 

cessation of injection, which may reduce the risk of leakage in certain cases. However, buoyancy 

forces causing upward migration of CO2 through geologic formations will remain for hundreds if not 

thousands of years following injection, long after over-pressures due to injection have dissipated in 

the injection zone. Furthermore, sequestration of CO2 by the aqueous phase and by precipitation of 

carbonates is very slow in relation to the 100-year time period specified. Finally, the specified leakage 

96
rate is very small compared to the expected volume of CO2 in geologic storage reservoirs, i.e., only 

about 2.4 tonnes CO2/yr. 

EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (§146.82(c)(3)). The data can 

help the Director determine the potential for geochemical reactions between the injectate (CO2) and 

the host geologic formations. For additional information on EPA’s approach to site characterization for 

Class VI GS wells, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28208 

Comment: Potential damage to USDWs from scenarios that are not consistent with the draft 

Class VI CO2 storage rule must be clearly identified as extreme cases. The 

scenario described in "Prediction of the Fate and Transport of Trace Elements" 

should have been presented as an extreme example of what can happen if virtually 

every aspect of the proposed Class VI rule is willfully ignored and/or not 

enforced. While this scenario might be useful in illustrating basin-scale 

behavior of geochemical and geomechanical reactions in aquifers, it is not 

helpful in terms of presenting how the USEPA intends to regulate the safe, 

effective deployment of CCS. The scenario posits that there is leakage of CO2 

for 100 years via a preferential pathway and under those circumstances "the MCL 

for arsenic was exceeded in only a few simulation scenarios." The July 2008 

proposed Class VI rule would require that actions be taken prior to injection 

(e.g., identification and remediation of any artificial penetration capable of 

transmitting CO2 out of the storage formation), during injection (e.g., high 

resolution monitoring to identify anomalous geophysical and injection findings 

that can serve as early warnings for leakage, groundwater, vadose zone and/or 

97
atmospheric monitoring), and after injection (via similar techniques) to 

identify leakage in time to allow mitigation efforts well in advance of any 

adverse impact such as the mobilization of arsenic into a USDW. Moreover, this 

kind of leakage rate parameterization defies our current understanding of the 

science and engineering of geologic CO2 storage {FOOTNOTE 5}. Given the flawed 

assumptions behind this analysis, the conclusion that "the MCL for arsenic was 

exceeded" seems quite a bit less robust. 

{FOOTNOTE 5} See for example. Dooley JJ, C Trabucchi, and L Patton. 2009. 

"Design Considerations for Financing a National Trust to Advance the Deployment 

of Geologic CO2 Storage and Motivate Best Practices." In press, the 

International Journal of Greenhouse Gas Control: GHGT9 Special Issue. October 

2009. 

Individual Response: EPA clarifies that the LBNL study was conducted to study the potential 

vulnerability of representative and relevant aquifer types in the case of CO2 intrusion, in order to 

provide sound scientific information as a basis for further studies on groundwater quality concerns. 

EPA understands (and mentioned in the NODA) that the risk of CO2 leaking from deep storage is low 

for properly managed GS projects, but the leakage probability is not necessarily zero (i.e., preinjection site characterization may fail to detect leakage pathway or monitoring during and after 

injection may miss small-scale signals of local leaks). Therefore, the potential consequences of 

unlikely leakage events need to be understood and predictive capabilities need to be developed as a 

basis for risk and vulnerability assessment (just like other scientific studies are being conducted 

evaluating the potential risks of CO2 leakage into the atmosphere). 

EPA agrees that the risk of leakage is highest during the injection period, and that leakage becomes 

less likely thereafter because of pressure reduction and increasing effects from solubility, capillary 

trapping, and carbonate mineralization. However, buoyancy forces causing upward migration of CO2 

through geologic formations will remain for hundreds if not thousands of years following injection, long 

after over-pressures due to injection have dissipated in the injection zone. Furthermore, some 

trapping mechanisms such as solubility trapping and mineralization are very slow in relation to the 

100-year time period specified. Finally, the specified leakage rate is low compared to the expected 

volume of CO2 in geologic storage reservoirs, i.e., only about 2.4 tonnes CO2/yr. Thus, as a 

simulation test case studying the potential water quality impacts of leakage, the 100-year time period 

selected in the LBNL study is reasonable. The time period was chosen to be able to evaluate both the 

short-term and the long-term geochemical consequences. 

EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

98
and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (§146.82(c)(3)). The data can 

help the Director determine the potential for geochemical reactions between the injectate (CO2) and 

the host geologic formations. For additional information on EPA’s approach to site characterization for 

GS wells, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28041 

Comment: API urges EPA not to take the results of the LBNL study out of context. First, 

the LBNL study goal, as stated in Apps et al. is to develop a "comprehensive 

geochemical model that describes the complete chemistry of a range of specified 

shallow aquifer systems" [Footnote 5]; the authors did not, contrary to EPA's 

assertion, model a "representative groundwater" (NODA p. 44807). Specifically, 

the groundwater samples chosen for the model had to have been tested for at 

least one of the following to be included in the study: As, Ba, Cd, Hg, Pb, Sb, 

Se, U, or Zn. These analyses are not commonly run in many parts of the U.S. or 

in aquifers known to be free of heavy metal constituents. There are many areas 

of the U.S. where the mobilization of arsenic, lead, and other trace elements is 

not a concern because the minerals in which these elements are typically found 

are not present. This does not make the LBNL results invalid, but it does 

indicate that the results may not be typical. It is also important to point out 

that the presence of minerals containing these elements would be taken into 

consideration during the site selection process. 

[Footnote 5] Apps, J. A., Zhang, Y., Zheng, L., Xu, T., and Birkholzer, J., 

2009, Identification of thermodynamic controls defining the concentrations of 

hazardous elements in potable ground waters and the potential impact of 

increasing carbon dioxide partial pressure, GHGT-9, Energy Procedia I, 

1917-1924. 

Second, heavy metal contamination will require multiple events and therefore the 

99
probability of occurrence of contamination is the product of the probabilities 

of each event, which in all likelihood will be very small. The events and 

associated probabilities will include: CO2 movement out of the intended storage 

zone, a migration path to a USDW, passing through or ending up in a unit with 

minerals that contain heavy metal assemblages, non-detection of a large-scale 

leak, no pH buffering or immobilization through mineral precipitation or 

adsorption onto clays/organics. The probability of USDW contamination, based on 

the probabilities of each of these individual events, will be different for 

every site. The risk of trace metal contamination of groundwater will typically 

be small, knowable, and manageable at properly selected and managed geologic 

storage sites. 

Third, actual field results - as opposed to modeling exercises - have shown the 

risk of contamination is low. For example, at SACROC oilfield in Scurry County, 

TX, where CO2 has been injected for EOR since 1972, Smyth et al., 2009 

determined that "[They] do not see evidence of As or Pb having been mobilized 

from injection zones at SACROC into overlying USDW's . . .". [Footnote 6] 

[Footnote 6]: Smyth, R.C., Hovarka, S., Lu, J., Romanak, K., Partin, J., Wong, 

C., and Yang, C., 2009, Assessing risk to fresh water resources form long term 

CO2 injection - laboratory and field studies, GHGT-9, Energy Procedia I: 

1957-1964. 

The LBNL report's authors realize the limitations to their models and EPA should 

also. Despite having set up the simulation so that trace element mobilization 

would likely result, the authors conclude that ". . . model uncertainties, 

kinetic factors, and post-withdrawal water treatment methods all suggest 

diligence rather than alarm." [Footnote 7] 

[Footnote 7]: Apps, J. A., Zhang, Y., Zheng, L., Xu, T., and Birkholzer, J., 

2009, Identification of thermodynamic controls defining the concentrations of 

hazardous elements in potable ground waters and the potential impact of 

increasing carbon dioxide partial pressure, GHGT-9, Energy Procedia I, 

1917-1924. 

Individual Response: EPA clarifies that in Apps et al. (2009), referenced in the LBNL study, one 

typical ground water composition and aquifer mineralogy scenario was modeled in order to determine 

the thermodynamic response of increasing CO2 partial pressures on the concentrations in groundwater 

of the nine cited elements: As, Ba, Cd, Hg, Pb, Sb, Se, U, or Zn. The purpose of the analysis was to 

establish the potential equilibrium concentrations of the cited elements in equilibrium with specified 

100
CO2 partial pressures. A range of specified shallow aquifer systems, all of which are representative of 

aquifers utilized for potable water, was then evaluated in the reactive transport simulations conducted 

in Section 4 of Birkholzer et al. (2008). 

EPA notes that all of the cited elements are generally present in natural ground waters regardless of 

location, albeit typically at trace concentrations. However, it is true that analyses for many potentially 

hazardous trace elements are not made routinely, and further, the analytical methods used have often 

been insufficiently sensitive to quantify the concentrations present. Birkholzer et al. (2008) evaluated 

concentrations in soils and sediments from the National Geochemistry Database (NGS) maintained by 

the USGS and also looked at evidence from crustal abundances and abundances in domestic coals. 

They concluded that many trace elements occur ubiquitously in soils, sediments, and aquifer rocks 

throughout the world.

EPA understands (and mentioned in the NODA) that the risk of CO2 leaking from deep storage is low 

for properly managed GS projects, but the leakage probability is not necessarily zero (i.e., preinjection site characterization may fail to detect leakage pathways, or monitoring during and after 

injection may miss small-scale signals of local leaks). Therefore, the consequences of unlikely leakage 

events need to be understood and predictive capabilities need to be developed as a basis for risk and 

vulnerability assessment. EPA agrees that risk assessment studies, as well as additional geochemical 

investigations on ground water vulnerability, should be site specific.

EPA notes the cited paper by Smyth et al. (2009) suggests that no contamination of an overlying 

aquifer has occurred at the SACROC oil field. However, the paper does not establish (1) if this is 

because no CO2 leakage occurred, (2) if leakage occurred but the leaking CO2 has not yet reached 

the aquifer, or (3) if CO2 has migrated into the aquifer but has not caused noticeable geochemical 

response. The latter is unlikely, as other studies have clearly suggested mobilization of metals in 

response to increased CO2 levels in the water. For example, the same cited paper by Smyth et al. 

(2009) reports on laboratory experiments with exposure of diverse aquifer rocks to CO2, showing 

geochemical response within hours to days after introduction of CO2. A recent paper by Kharaka et al. 

(2009) reports on a field experiment with injection of CO2 into shallow groundwater, also showing a 

rapid and systematic geochemical response in the aquifer, with concentration increases observed for 

several trace metals. These studies support the LBNL findings suggesting that CO2 intrusion into 

USDW, however unlikely, can lead to mobilization of trace elements. 

EPA clarifies that all GS project owner or operators must submit detailed, site-specific information 

about a proposed GS site, including information on the porosity, permeability, mineralogy, and 

geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (§146.82(c)(3)). For additional 

information on EPA’s approach to site characterization for GS wells, see the responses to comments on 

the proposed rule in the rulemaking docket. 

101
EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text that is later repeated in lines 172 to 193. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27937 

Comment: DATA AND RESEARCH ON GS AND THE IMPACTS ON GROUNDWATER 

The NODA provides a summary of Lawrence Berkeley National Laboratory (LBNL) 

theoretical studies on the interactions between groundwater, CO2 and the 

surrounding geology. Simulations of the potential for GS to cause changes in 

groundwater quality and the subsequent mobilization of trace elements (including 

arsenic and lead) as a result of CO2 leakage were developed. The modeling 

studies also addressed basin-scale hydrological impacts of large-volume 

injections of CO2 on groundwater aquifers (in particular, pressure front 

impacts caused by GS). 

Results from the model simulations suggest that mobilization of lead and arsenic 

would occur with leaking of CO2 into shallow aquifers. This is unacceptable to 

drinking water utilities and to millions of consumers of groundwater in the 

United States. Model projections note that the Maximum Contaminant Levels (MCL) 

for arsenic would be exceeded in only a few cases. However, this does not 

address the fact that water utilities do not want their USDWs contaminated by 

arsenic or other contaminants in any quantity as a result of GS projectsr. In 

the case of lead, the model analysis incorrectly assumes that the Action Level 

for lead in the Lead and Copper Rule is a health based limit, whereas it is 

simply an indicator of effective corrosion control. In regard to acceptable 

lead concentrations, the model should address the Maximum Contaminant Level Goal 

(MCLG) which for lead is zero. Given that small concentrations of lead are 

detrimental to the mental development of children, any possible increase in lead 

in water either by mobilization in the source or corrosion of plumbing is 

unacceptable. Injected carbon dioxide that reaches USDWs is likely to make the 

groundwater water more corrosive with respect to lead and copper in distribution 

systems. This would increase the probability of elevated lead levels in homes 

102
and schools due to corrosion of plumbing fixtures. Any increase in raw water 

lead concentration constrains the utility in compliance with its optimized 

corrosion control treatment. 

EPA should be mindful of not only the health risks to drinking water, but also 

of other potential secondary standard and aesthetic degradation risks from 

exposure to other constituents such as pH, copper, iron, hardness, silica and 

boron. These are compounds for which either no MCLs have been developed or have 

secondary MCLs. Further, in states like California, water utilities must report 

Public Health Goals (PHGs) well below federal MCLs to the public. 

Given the basis for MCLs, there is the potential for health impacts due to longterm exposure to contaminant levels below the established MCLs. Technically, 

MCLs are not the proper limit on which to base degradation. Drinking water MCLs 

should not be a license to pollute or contaminate. Drinking water MCLs are 

established from a different reference point. Rather than starting with a 

pristine condition and adding a contaminant, MCLs are established from sources 

that contain a contaminant. The exposure assessment and risk assessment 

components of a risk management decision resulting in an MCL are developed on 

the basis of population exposure. If the population is not exposed at present, 

the economic and health benefits/costs are not included in the choice or 

selection of an MCL. If a new segment of the population or a greater segment of 

the existing population becomes exposed as a result of an activity, the economic 

impact and benefit on this new population will not have been included in the 

risk management decision. One can assume the impact would increase 

proportionally, but there are no data to justify such an assumption. 

Owners/operators could be in compliance with the regulation, but could be 

degrading an aquifer by contaminating it with compounds for which MCLs may or 

may not exist. Beneficial uses of groundwater could also be impacted by 

increases of these compounds in the aquifers. Research is needed to address 

these topics as well, not just on the potential for the mobilization of lead and 

arsenic due to the leakage of CO2 into shallow aquifers. 

In addition, drinking water standards are not static and can change as a result 

of new studies. Arsenic is a good example as the MCL was lowered from 50 ppb to 

10 ppb in 2001. GS operations should not be immune from the new requirements 

and should not have their permits grandfathered into compliance without 

adjusting the compliance objectives. Also, lead and copper action levels are 

not health based water quality standards and should not be used as an objective 

103
or yardstick with which to measure adequacy of remedial measures. 

Individual Response: EPA clarifies that the LBNL study was conducted to study the potential 

vulnerability of representative and relevant aquifer types in the unlikely case of CO2 intrusion, in order 

to provide sound scientific information as a basis for further studies on groundwater quality concerns. 

LBNL’s work does not suggest that leakage of CO2 is likely; in fact it is mentioned in the NODA that 

the risk of CO2 leaking from deep storage is low for properly managed GS projects. 

EPA clarifies that the MCLs, MCLGs, and ALs cited in the study were presented in LBNL’s work as a 

reference point for comparison purposes. The LBNL study makes no assertion about drinking water 

standards. EPA acknowledges that any increase in concentration of metals is undesirable to water 

utilities and the final rule requirements were established to maximize protection of USDWs. EPA 

clarifies that potential geochemical reactions that may cause mobilization or mineralization are an 

important consideration in GS permitting decisions. For this reason, all GS project owner or operators 

must submit detailed, site-specific information about a proposed GS site, including information on the 

porosity, permeability, mineralogy, and geochemistry of the targeted injection and confining zones as 

well as all USDWs within the Area of Review. Operators must also present information on the 

compatibility of the CO2 stream with fluids in the injection zone and minerals in the injection and 

confining zones (§146.82(c)(3)). For additional information on EPA’s approach to site characterization 

for GS wells, see the responses to comments on the proposed rule in the rulemaking docket.

EPA notes the LBNL study did not address the question of increased partial pressures of CO2 dissolved 

in water causing corrosion in water distribution systems or plumbing fixtures. However, the dissolved 

CO2 would likely degas upon withdrawal from the aquifer, making corrosion in distribution systems 

unlikely. As noted, other constituents such as iron, manganese, silica, copper, and boron could also be 

mobilized and their concentrations in the aquifer water could increase, depending on aquifer 

mineralogy and prevailing redox conditions. As with other species that were examined, the extent of 

mobilization, and its significance in relation to drinking water quality, would have to be characterized 

on a site-specific basis. 

EPA agrees that temporary hardness could also become an issue in the unlikely case of CO2 intrusion. 

However, degassing of the dissolved CO2 would induce the precipitation of carbonates with coprecipitation of many of the cited hazardous elements, and could actually decrease their 

concentrations to levels lower than present in uncontaminated water. This phenomenon, while 

theorized, has neither been modeled nor evaluated experimentally. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-JUL-10 

Notes: 

104
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27938 

Comment: Ground Water Quality Changes 

The LBNL report on computer model simulations of changes in groundwater changes 

due to CO2 leakage supports AWWA’s position that more research is needed to 

develop a better understanding of the potential impacts of GS projects on USDW. 

In particular, AWWA supports the LBNL recommendation that field research be done 

with "shallow" groundwater sources being used for water supply. 

AWWA notes that the report apparently has not been peer reviewed. We recommend 

that EPA conduct a peer review of both the report and the modeling approach. 

The peer review should be performed by a panel of experts of qualified 

practitioners familiar with groundwater chemistry, fate and transport modeling, 

and drinking water treatment and regulations. This could be accomplished using 

the EPA Science Advisory Board Drinking Water Committee or the National 

Academies of Science as the review panel. At a minimum, the following topics 

should be considered: 

- The model simulations involve numerous assumptions that should be verified on 

site specific groundwater supplies. The panel should provide recommendations on 

specific research needs. 

-Lead dissolution by CO2 is being compared to the action level for lead, which 

is actually applied to the customer tap rather than the source water. The fact 

that CO2 intrusion would make the source water more corrosive could cause noncompliance with the lead and copper rule, even if the lead is below the action 

level. 

- LBNL did not evaluate impacts of CO2 leakage on copper mobilization, which 

could be affected by more corrosive water produced by CO2 intrusion. Copper also 

has an action level that applies at the customer tap. 

- The LBNL report covers natural analogues of CO2 intrusion into groundwater. 

These analogues suggest that high levels of hardness, iron, manganese, and boron 

could be produced. While these adverse water quality changes would not currently 

105
come under the definition of endangerment (boron and manganese could be future 

exceptions), they would degrade groundwater quality and limit beneficial use of 

water resources. 

Individual Response: EPA clarifies that the LBNL study was conducted to study the potential 

vulnerability of representative and relevant aquifer types in the unlikely case of CO2 intrusion, in order 

to provide a foundation for further studies on ground water quality concerns, such as site-specific 

studies including laboratory and field experiments and associated modeling. EPA notes that one field 

study has been conducted, while other research work is ongoing or planned. For example, Kharaka et 

al. (2009) reports on a field experiment with injection of CO2 into shallow groundwater and water 

quality measurements. In addition, the Agency plans, every six years, to collect and review data on 

GS projects and research to determine whether the appropriate amount and types of information and 

appropriate documentation are being collected, and to determine if modifications to the requirements 

are appropriate or necessary.

EPA notes that two scientific manuscripts summarizing LBNL’s study have since been published, both 

of which were peer-reviewed (i.e., Apps et al., 2009; Zheng et al., 2009). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28116 

Comment: 3. The NODA raises a question about the mobilization of metals from CO2 

injection. However, there is no concurrent risk analysis provided or cited. 

While we recognize that mobilization of metals in the injection zone can occur 

under specific circumstances, we believe the containment requirements of the 

proposed rule are adequate to prevent contamination of USDW’s from the movement 

of CO2 and associated formation fluids in the injection zone. Consequently, we 

believe mobilization of metals in the injection zone is not a concern provided 

formation fluids remain in the injection zone. 

106
Individual Response: EPA agrees that contamination of USDWs would not be a concern provided 

formation fluids remain in the injection zone. It is mentioned in the NODA that the risk of fluids 

leaking from deep storage is low for properly managed GS projects, but it may not be completely 

ruled out. Therefore, the potential consequences of unlikely leakage events need to be understood and 

predictive capabilities need to be developed as a basis for risk and vulnerability assessment.

Site specific risk analyses should be undertaken in order to determine the probability of CO2 (and 

associated formation fluids) leaking from the storage reservoir. EPA clarifies that all GS project owner 

or operators must submit detailed, site-specific information about a proposed GS site, including 

information on the porosity, permeability, mineralogy, and geochemistry of the targeted injection and 

confining zones as well as all USDWs within the Area of Review. Operators must also present 

information on the compatibility of the CO2 stream with fluids in the injection zone and minerals in the 

injection and confining zones (§146.82(c)(3)). The data can help the Director determine the potential 

for geochemical reactions between the injectate (CO2) and the host geologic formations. For 

additional information on EPA’s approach to site characterization for GS wells, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28171 

Comment: 2. LBNL Study of Ground Water Quality Changes Related to the Mobilization of 

Trace Elements, If CO2 Leakage is Assumed to Occur 

We agree with EPA that it is important to recognize that these studies describe 

what happens if one assumes that CO2 leaks. The studies do not describe or 

model the risks of actual CO2 leakage, nor should their results be taken as 

supporting the idea that there is high risk of such leakage. The LBNL study 

described in the NODA investigated trace element geochemical changes in 

"representative" potable aquifers under the assumption of leaked CO2, which does 

not represent the expected result of CO2 injection at large scale. We agree with 

EPA that the goal of the UIC program and these regulations is to ensure that the 

risk of such leakage into USDWs is low. 

107
The results of the LBNL study to date suggest that UIC Class VI permits must be 

based on submitted information that is sufficient to establish whether the AOR 

contains a high or low hazard trace element leaching environment. Specifically, 

the LBNL study of the fate and transport of trace elements highlights the need 

for geochemical screening of reservoir rock in potential GS sites. In the case 

of formations characterized by hazardous trace element mineralogy where brine 

leaching could result in pore water that contains trace elements exceeding the 

maximum contaminant levels (MCLs) and Action Levels (ALs), EPA must ensure that 

the rule language results in the issuance of permits that take into account the 

potentially higher risks involved. In particular, the rule should ensure that 

permits issued in this context will require both baseline geochemical studies 

and monitoring of any geochemical changes above and below the confining zone. 

Individual Response: EPA agrees that LBNL’s study should not be taken as supporting the idea that 

there is high risk of leakage and contamination of USDWs from GS activities. It is mentioned in the 

NODA that the risk of fluids leaking from deep storage is low for properly managed GS projects, but it 

may not be completely ruled out. Site specific risk analyses should be undertaken in order to 

determine the probability of CO2 (and associated formation fluids) leaking from the storage reservoir. 

EPA agrees that geochemical screening of reservoir rock in potential GS sites, as well as screening of 

overlying USDW geochemistry, should be part of GS site characterization. For this reason, all GS 

project owner or operators must submit detailed, site-specific information about a proposed GS site, 

including information on the porosity, permeability, mineralogy, and geochemistry of the targeted 

injection and confining zones as well as all USDWs within the AoR. Operators must also present 

information on the compatibility of the CO2 stream with fluids in the injection zone and minerals in the 

injection and confining zones (§146.82(c)(3)). The data can help the Director determine the potential 

for geochemical reactions between the injectate (CO2) and the host geologic formations. For 

additional information on EPA’s approach to site characterization for GS wells, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28096 

108
Comment: Risk to Groundwater from Trace Element Mobilization 

APC urges EPA to not take the results of the LBNL study out of context or as 

more conclusive than they are. The NODA even states that the model results were 

based on "several assumptions and parameter values with a large degree of 

uncertainty" (NODA, p.44807). It must also be noted that the LBNL study goal was 

not, contrary to EPA’s assertion, to model a 'representative groundwater" (NODA 

p. 44807). 

The probability of trace element contaminating groundwater requires the 

multiplied probabilities of CO2 movement out of the intended storage zone, 

finding a migration path to a USDW, passing through or ending up in a zone with 

minerals that contain heavy metal assemblages, environmental conditions 

favorable to dissolution, and an undetected, unremediated leak that mobilizes 

these elements into a USDW as opposed to immobilizing them through mineral 

precipitation or adsorption onto clays/organics. The probability of USDW 

contamination, based on the probabilities of each of these individual events, 

will be different for every site. The risk of trace metal contamination of 

groundwater will typically be small, knowable, and manageable at well selected 

and managed geologic storage sites as noted in the text "the majority of results 

did not show mobilization at levels exceeding the MCL or AL" (NODA, p. 44807). 

Also, actual field results - as opposed to the modeling exercise - have shown 

the risk of contamination is low. For example, at SACROC oilfield in Scurry 

County, TX, CO2 has been injected for EOR since 1972, and according to recent 

publications they have not seen evidence of certain elements mobilized from 

injection zones at SACROC into overlying USDWs (reports referenced in detail in 

both the API’s NODA response as well as the CSC’s NODA response). The LBNL 

report’s authors realize the limitations to their models and EPA should also. 

Despite having set up the simulation so that trace element mobilization would 

likely result, the authors conclude that ". . . model uncertainties, kinetic 

factors, and post-withdrawal water treatment methods all suggest diligence 

rather than alarm." 

Individual Response: EPA clarifies that the LBNL study was conducted to study the potential 

vulnerability of a wide range of aquifer types in the unlikely case of CO2 intrusion to provide a 

foundation for further studies on ground water quality concerns, such as site-specific studies including 

laboratory and field experiments and associated modeling with the objective of reducing uncertainty of 

assumptions and parameters. 

109
EPA notes that all of the cited elements (and others not cited here) are generally present in natural 

ground waters regardless of location, albeit typically at very small (i.e., trace) concentrations. 

However, it is true that analyses for many potentially hazardous trace elements are not made 

routinely, and that the analytical methods used have often been insufficiently sensitive to quantify the 

concentrations actually present. Regarding the presence or absence of minerals hosting the potentially 

hazardous trace elements, very few studies have been conducted on the mineralogy of potable water 

aquifer host rocks in which the modes of occurrence of trace elements have been characterized. 

Birkholzer et al. (2008) evaluated concentrations in soils and sediments from USGS’ National 

Geochemistry Database andlooked at evidence from crustal abundances and abundances in domestic 

coals. They concluded that many trace elements occur ubiqui¬tously in soils, sediments, and aquifer 

rocks throughout the world.

EPA agrees (and mentioned in the NODA) that the risk of CO2 leaking from deep storage is low for 

properly managed GS projects, but the leakage probability is not necessarily zero (i.e., pre-injection 

site characterization may fail to detect leakage pathways or monitoring during and after injection may 

miss small-scale signals of local leaks). Therefore, the potential consequences of unlikely leakage 

events need to be understood and predictive capabilities need to be developed as a basis for risk and 

vulnerability assessment. 

EPA agrees that risk assessment studies, as well as additional geochemical investigations on ground 

water vulnerability, should be site specific. For this reason, all GS project owner or operators must 

submit detailed, site-specific information about a proposed GS site, including information on the 

porosity, permeability, mineralogy, and geochemistry of the targeted injection and confining zones as 

well as all USDWs within the AoR. Operators must also present information on the compatibility of the 

CO2 stream with fluids in the injection zone and minerals in the injection and confining zones 

(§146.82(c)(3)). The data can help the Director determine the potential for geochemical reactions 

between the injectate and the host geologic formations. For additional information on EPA’s approach 

to site characterization for GS wells, see the responses to comments on the proposed rule in the 

rulemaking docket.

EPA notes the cited paper by Smyth et al. (2009) suggests that no contamination of an overlying 

aquifer has occurred at the SACROC oil field. However, the paper does not establish (1) if this is 

because no CO2 leakage occurred, (2) if leakage occurred but the leaking CO2 has not yet reached 

the aquifer, or (3) if CO2 has migrated into the aquifer but has not caused noticeable geochemical 

response. The latter is unlikely, as other studies clearly suggested mobilization of metals in response 

to increased CO2 levels in the water. For example, the same cited paper by Smyth et al. (2009) 

reports on laboratory experiments with exposure of diverse aquifer rocks to CO2, showing 

geochemical response within hours to days after introduction of CO2. Kharaka et al. (2009) report on 

a field experiment with injection of CO2 into shallow groundwater, also showing a rapid and 

systematic geochemical response in the aquifer, with concentration increases observed for several 

trace metals. These studies support the LBNL findings that CO2 intrusion into USDW, however 

110
unlikely, can lead to mobilization of trace elements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27961 

Comment: Comment No. 12 

Page 44807 

Issue Topic from EPA's NODA 

LBNL conducted multiple model runs to assess a variety of scenarios and aquifer 

conditions and, as discussed below, found that if injected CO2 comes into 

contact with shallow USDWs, some trace element concentrations such as arsenic 

could increase. 

Carbon Sequestration Council Comments 

The LBNL study goal, as stated in Apps, et al., 2009, is to develop a 

"comprehensive geochemical model that describes the complete chemistry of a 

range of specified shallow aquifer systems". In reality, they did not model a 

"representative groundwater" (NODA p. 44807). See Attachment A. 

[Reference]: Apps, J. A., Zhang, Y., Zheng, L., Xu, T., and Birkholzer, J., 

2009, Identification of thermodynamic controls defining the concentrations of 

hazardous elements in potable ground waters and the potential impact of 

increasing carbon dioxide partial pressure, GHGT-9, Energy Procedia I, 

1917-1924. 

Individual Response: EPA clarifies that in Apps et al. (2009), referenced in the LBNL study, one 

typical (average) ground water composition and aquifer mineralogy was modeled in order to 

determine the thermodynamic response of increasing CO2 partial pres¬sures on the concen¬trations 

111
in groundwater of As, Ba, Cd, Hg, Pb, Sb, Se, U, or Zn. The purpose of the analysis was to establish 

the potential equilibrium concentrations of these elements in equilibrium with specified CO2 partial 

pressures. A range of specified shallow aquifer systems, all of which are representative aquifers 

utilized for potable water, was then evaluated in the reactive transport simulations conducted in 

Section 4 of Birkholzer et al. (2008). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27962 

Comment: Comment No. 13 

Page 44807 

Issue Topic from EPA's NODA 

A preliminary assessment of CO2 -related water quality changes, including pH, 

was conducted by calculating the expected equilibrium concentrations of trace 

elements as a function of the amount of CO2 in a representative potable 

groundwater. Results of this modeling obtained for typical aquifers under 

reducing conditions indicate that arsenic could potentially exceed Federal 

drinking water standards at elevated CO2 concentrations (40 CFR 141.62 (b)(16)). 

Carbon Sequestration Council Comments 

The groundwater samples chosen for the model had to have been tested for at 

least one of the following to be included in the study: As, Ba, Cd, Hg, Pb, Sb, 

Se, U, or Zn. These analyses are not commonly run in parts of the U.S. or in 

aquifers known to be free of heavy metal contamination. There will likely be 

many areas of the U.S. where the mobilization of arsenic, lead, and other trace 

elements is not a concern because the minerals that these elements are typically 

found in are not present in those formations. This does not necessarily render 

the LBNL results invalid, but it does indicate that the results may not be 

typical and thus not representative. 

112
Comment No. 14 

Page 44807 

Issue Topic from EPA's NODA 

Other trace elements, such as barium, cadmium, lead, antimony, and zinc, may 

also be mobilized in certain circumstances, but the majority of results did not 

show mobilization at levels exceeding the MCL or AL. (action level) 

Carbon Sequestration Council Comments 

The modeling used a number of assumptions in order to test scenarios where trace 

element mobilization was likely to occur. The results focused on whether or not 

given elements would exceed the maximum contaminant levels (MCLs), not whether 

mobilization would realistically occur in various scenarios. 

Individual Response: EPA notes that all of the cited elements included in LBNL’s study (and others 

not cited here) are generally present in natural ground waters regardless of location, albeit typically at 

very small (i.e., trace) concentrations. However, it is true that analyses for many potentially 

hazardous trace elements are not made routinely, and further, that the analytical methods used have 

often been insufficiently sensitive to quantify the concentrations actually present. Regarding the 

presence or absence of minerals hosting the potentially hazardous trace elements, very few studies 

have been conducted on the mineralogy of potable water aquifer host rocks in which the modes of 

occurrence of trace elements have been characterized. Birkholzer et al. (2008) evaluated 

concentrations in soils and sediments from the National Geochemistry Database (NGS) maintained by 

the USGS and also looked at evidence from crustal abundances and abundances in domestic coals. 

They concluded that many trace elements occur ubiquitously in soils, sediments, and aquifer rocks 

throughout the world.

The objective of LBNL’s study was to better understand, in a global sense, the vulnerability of 

representative and relevant aquifer types in the case of CO2 intrusion. It was therefore assumed that 

CO2 leakage into a USDW would occur through a local pathway and the evolution of USDW water 

quality was predicted for a leakage period of 100 years. The risk of CO2 leaking from deep storage is 

low for properly managed GS projects; thus this assumption is testing the unlikely scenario that CO2 

leaks. All other assumptions made in the study (e.g., regarding aquifer geochemistry and mineralogy) 

are considered realistic, although not specific to any particular site. 

EPA agrees that the results of the LBNL study or the presence of the metals cited may not be typical of 

113
all GS sites, and believes that site-specific data are necessary to understand the potential geochemical 

reactions at a GS site. For this reason, all GS project owner or operators must submit detailed, sitespecific information about a proposed GS site, including information on the porosity, permeability, 

mineralogy, and geochemistry of the targeted injection and confining zones as well as all USDWs 

within the Area of Review. Operators must also present information on the compatibility of the CO2 

stream with fluids in the injection zone and minerals in the injection and confining zones 

(146.82(c)(3)). The data can help the Director determine the potential for geochemical reactions 

between the injectate (CO2) and the host geologic formations. For additional information on EPA’s 

approach to site characterization for GS wells, see the responses to comments on the proposed rule in 

the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27963 

Comment: Comment No. 15 

Page 44807 

Issue Topic from EPA's NODA 

While LBNL studies did suggest that CO2 interaction could cause significant 

concentration increases compared to the initial water composition, the MCL for 

arsenic was exceeded in only a few simulation scenarios, while the lead 

concentrations remained below the AL under all scenarios. 

Carbon Sequestration Council Comments 

To the extent that these studies could be viewed as presenting extreme 

scenarios, some comfort might be drawn from such results. We are concerned, 

however, with the absence of realistic scenarios, as noted below. It is more 

appropriate to view the studies to date as a preliminary test of the methods and 

models. Subsequent testing might provide useful results as realistic scenarios 

are developed and particularly as the methods can be tested with actual project 

114
site characteristics. The identification of methodologies and potential 

approaches is useful by itself as a step toward site assessment and the 

development of operation and management plans. 

Individual Response: EPA notes the generic simulation conditions and site characteristics were 

generally realistic given the current state of knowledge. LBNL did not address the question of the 

likelihood of leakage. This topic is a subject for risk analysis, and is distinct from the development of 

realistic geochemical models. EPA acknowledges the commenter’s point that further site-specific 

studies are recommended including laboratory experiments and field experiments, as well as 

evaluation of natural analogs. As part of its adaptive approach to the GS regulation, EPA plans, every 

six years, to collect and review data on GS projects to determine whether the appropriate amount and 

types of information and appropriate documentation are being collected, and to determine if 

modifications to the requirements are appropriate or necessary.

EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (146.82(c)(3)). The data can help 

the Director determine the potential for geochemical reactions between the injectate (CO2) and the 

host geologic formations. For additional information on EPA’s approach to site characterization for GS 

wells, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27964 

Comment: Comment No. 16 

Page 44807 

Issue Topic from EPA's NODA 

115
It is important to emphasize that these studies looked at potential consequences 

of CO2 leakage into the USDW, not the likelihood of such leakage occurring. 

Carbon Sequestration Council Comments 

The probability of trace element contamination of groundwater requires the 

multiplied probabilities of CO2 movement out of the intended storage zone, 

finding a migration path to a USDW, passing through or ending up in a unit with 

minerals that contain heavy metal assemblages, environmental conditions 

favorable to dissolution, and an undetected, unremediated leak that mobilizes 

these elements. The probability of USDW contamination, based on the 

probabilities of each of these individual events, will be different for every 

site. The risk of trace metal contamination of groundwater will typically be 

small, knowable, and manageable at well selected and managed geologic storage 

sites. 

Comment No. 17 

Page 44808 

Issue Topic from EPA's NODA 

The Agency will use these preliminary results and public comments on this 

research as well as potential site-specific analyses, to refine and inform site 

characterization, monitoring, and remediation requirements and guidance, if 

necessary, in the Agency's final rulemaking. 

Carbon Sequestration Council Comments 

In general, reactive transport modeling represents the correct method of 

evaluating the possible impacts on USDWs by the leakage of CO2 from an 

underlying CCS reservoir. The LBNL work verifies that TOUGHREACT reactive 

transport modeling technology is suitable for this purpose. However, the results 

reported by Zheng et al. are based on hypothetical cases. They should not be 

used to establish regulations because: (1) these results have not been validated 

for analog scenarios; (2) the recompiled thermodynamic data they used have not 

been verified by experimental data; (3) more realistic conditions and processes 

such as the migration of a mixture of CO2 -saturated reservoir brine, 

supercritical CO2, and/or other gases are not considered; and (4) their model 

does not integrate dynamic effects during the loss of containment for a CCS 

116
reservoir. 

Individual Response: EPA agrees (and mentioned in the NODA) that the risk of CO2 leaking from 

deep storage is low for properly managed GS projects, but the leakage probability is not necessarily 

zero (i.e., pre-injection site characterization may fail to detect leakage pathways or monitoring during 

and after injection may miss small-scale signals of local leaks). Therefore, the potential consequences 

of unlikely leakage events need to be understood and predictive capabilities need to be developed as a 

basis for risk and vulnerability assessment. EPA agrees that risk assessment studies, as well as 

additional geochemical investigations on ground water vulnerability, should be site specific.

EPA clarifies that CO2 is not likely to reach a shallow potable water aquifer in a supercritical state and 

believes that the assumed leakage scenario is reasonable. EPA agrees with the commenter that 

further studies would be beneficial, including validation of the predictive models using laboratory 

experiments and field experiments as well as evaluation of natural analogs. EPA also acknowledges 

that even a comprehensive sensitivity study cannot encompass all possible scenarios, conditions and 

processes, and agrees that additional investigations could be conducted (e.g., regarding the comigration of CO2-brine mixtures, as well as dynamic effects related to loss of containment). It should 

be noted that most of the thermodynamic data and some of the kinetic data are based on 

experimental studies reported in the literature. As part of its adaptive rulemaking approach, EPA 

plans, every six years, to collect and review data on GS projects to determine whether the appropriate 

amount and types of information and appropriate documentation are being collected, and to determine 

if modifications to the requirements are appropriate or necessary.

EPA adds that it is not the intent to use the study to specify which models are to be used in AoR 

delineations, and also clarifies that the GS regulation does not specifically require reactive transport 

modeling for AoR delineation. EPA believes that flexibility in selecting models is appropriate. For 

additional information on EPA’s approach to AoR delineation for GS wells, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27965 

117
Comment: Comment No. 18 

Page 44808 

Issue Topic from EPA's NODA 

The Agency seeks comment on this research and any additional studies related to 

a) mobilization of constituents and b) the likelihood or frequency of such 

leakage/risks. 

Carbon Sequestration Council Comments 

See the following references (full citation in "References" below): Smyth, R.C., 

et al., 2009 Koplos, J., 2007 Duncan, et al., 2009 

[References]: 

Smyth, R.C., Hovarka, S., Lu, J., Romanak, K., Partin, J., Wong, C., and Yang, 

C., 2009, Assessing risk to fresh water resources form long term CO2 injection - 

laboratory and field studies, GHGT-9, Energy Procedia I: 1957-1964 - paper GCCC 

Digital Publication Series #08-03j, presented at the 9th International 

Conference on Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., 

November 16-20, 2008. Download from BEG/UT website: 

http://www.beg.utexas.edu/gccc/bookshelf/2008/GHGT9/08-03j-Final.pdf. 

Koplos, J., 2007, A Review of Injection Well Mechanical Integrity Testing Data 

and Implications for Geosequestration, IEA GHG 3rd Wellbore Integrity Network 

Meeting, Santa Fe, 2007. 

Duncan, I., Nicot, J. P., and Choi, J., 2009, Risk assessment for future CO2 

sequestration projects based on CO2 enhanced oil recovery in the U.S., GHGT-9, 

Energy Procedia I, 2037-2042 - presented at the 9th International Conference on 

Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., November 16-20, 

2008. GCCC Digital Publication Series #08-03i. 

Individual Response: EPA acknowledges the studies cited and believes they are a valuable 

contribution to knowledge in the area of risk assessment of GS wells and has reviewed them in the 

course of the rulemaking process. EPA adds that the reference by Koplos is a presentation based on 

an EPA-funded study that informed the final MIT requirements for GS wells. They are in the final 

rulemaking docket.

118
EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (146.82(c)(3)). The data can help 

the Director determine the potential for geochemical reactions between the injectate (CO2) and the 

host geologic formations. For additional information on EPA’s approach to site characterization for GS 

wells, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 28001 

Comment: Attachment A 

October 15, 2009 

Detailed Comments of the Carbon Sequestration Council 

regarding: 

Birkholzer, J., J. Apps, L. Zheng, Y. Zhang, T. Xu, and C.-F. Tsang, 2008. 

Research Project on CO2 Geological Storage and Groundwater Resources: Water 

Quality Effects Caused by CO2 Intrusion into Shallow Groundwater, Technical 

Report 2008, Earth Sciences Division, Lawrence Berkeley National Laboratory. 

Observations 

Stated project goal: 

o Develop a general understanding of the potential vulnerability of United 

States potable groundwater resources in the event of CO2 leakage into potable 

aquifers. 

119
Major tasks: 

o Developed comprehensive geochemical model representing what are presented as 

"typical" conditions in many freshwater aquifers 

o Conduct systematic reactive transport study to quantify effects of CO2 

intrusion into shallow groundwater aquifers 

Subtasks: 

o Identify mineral hosts controlling solubility 

-Data from ore and coal mineralogy 

o Conduct thermodynamic analysis of water samples 

-Data from USGS NWIS database 

o Improve thermodynamic data where necessary 

Comments: 

o Overall comments: 

o The modeling effort is screening level and contains many 

uncertainties. 

o The conclusion that As may exceed the maximum contaminant level (MCL) 

is limited to a few modeling scenarios that are localized and shortterm effects. 

o Conclusions could be viewed as issues that might warrant further 

investigation through field-scale experimentation, but cannot 

reasonably be viewed as evidence of eminent risk posed by CO2 geologic 

sequestration. 

o Project Goal: 

o The goal of the study was to evaluate the effects that CO2 migration 

into drinking water aquifers might have with respect to mobilizing 

trace elements and exceeding drinking water standards. The authors 

120
were very clear that the study was conducted as a screening level 

assessment. The scope of this particular study was exceptionally 

broad, which required broad assumptions to be made. Conclusions from 

the study should be viewed as theoretical geochemical reactions that 

might warrant further investigation under circumstances where site 

characteristics and operational experience indicate a significant 

potential for leakage, rather than evidence that eminent risks are 

posed by CO2 geologic sequestration. No model created by the authors 

can be viewed as reflecting an actual aquifer composition; therefore 

no conclusion can be implied to represent an actual risk. 

o Geochemical Model Development: 

o The authors created "typical" aquifer conditions by combining 

assumptions related to major mineralogy, trace element mineralogy and 

groundwater analyses into a theoretical aquifer condition. Any 

conclusion derived from the study is fictive. Some aquifers may not 

contain natural arsenic at concentrations posing any significant risk 

for future mobilization. 

o Reactive transport and sensitivity analysis: 

o Results showed that, while Pb and As were modeled to be mobilized by 

geochemical reactions resulting from CO2 intrusion, Pb concentrations 

did not exceed the MCL. As concentrations exceeded the MCL in only a 

few simulation cases. 

o Sensitivity analyses of the Coastal Plain aquifer example showed that 

there are many cases where As does not exceed the MCL when CO2 is 

introduced to the system. These cases include: 

- When initially adsorbed arsenic is assumed negligible, 

eliminating an initial pulse of arsenic that is desorbed from 

the aquifer matrix: 

- In the study, the occurrence of a MCL exceedance for 

As is suggested when adsorption is neglected, but no 

modeling evidence is presented to verify the 

suggestion. Therefore, the suggestion is 

unsubstantiated. 

121
- When adsorption surface site densities are low, creating less 

adsorption sites for initially adsorbed arsenic: 

- The primary adsorbing surface in the model is illite, 

a clay mineral. Surface site densities for illite may 

be lower than assumed in the base case, creating less 

opportunity for local and short-term mobilization of 

As above the MCL. This is acknowledged by the 

authors. 

- In the base case, illite comprises 2.85% of the rock 

composition by weight. Evidence from deep coastal plain 

sandstones suggests that illite may comprise only 1% of 

the rock composition by weight. This lower percentage 

would effectively reduce the potential for initial 

arsenic mobilization, but would ensure potential for 

long-term adsorption of arsenic and limiting arsenic 

aqueous concentrations below the MCL. 

- When the arsenopyrite solubility product is reduced: 

- The authors illustrated that minor reductions in the 

solubility of arsenopyrite can result in substantially 

lower aqueous As concentrations during reactive 

transport analysis. No MCL exceedances occurred with a 

reduced solubility product. 

o Initially elevated partial pressures of CO2(g) may result in As 

concentrations exceeding the MCL prior to additional CO2(g) migration 

into the aquifer. This case must be considered as a strong 

possibility. 

o Mineral hosts controlling trace element solubility: 

o The model assumes that trace element mineral hosts in typical aquifers are the 

same as those found in coal and ore materials. A lack of additional 

information has resulted in the construction of a purely fictive scenario, 

which is the case in many screening level modeling efforts. This is 

recognized by the authors as a limitation. Although the authors make a sound 

attempt at the project scope with available data, it is not at all clear that 

there is enough information available to make the entire modeling effort 

122
worthwhile. 

o Thermodynamic analysis of water samples: 

o Assessing the saturation state and solubility of various mineral 

phases relies heavily upon accurate reconstruction of initial in situ 

pH and carbonate species distribution, specifically pCO2(g). The 

authors point out numerous complications with pH and initial pCO2(g) 

reconstruction - a common problem with deep and shallow aquifer 

characterization. It is critically important to understand that 

modeling simulation results should be viewed as relative changes to an 

assumed initial condition. The uncertainty of an initial condition is 

multiplied when that assumed condition is perturbed. Any projected 

exact result, such as the occurrence of a particular As concentration 

(0.01 mg/L), should be viewed with appropriate caution. 

o Improvement of thermodynamic data: 

o Improvement of thermodynamic data based on the NWIS database is a 

questionable approach, given the complications arising from 

inconsistent sampling and analysis methods that the authors point out. 

Individual Response: In general, EPA agrees with the commenter’s observations of Birkholzer et al. 

(2008), in particular with respect to model uncertainties and the need for further (site-specific) studies 

including laboratory and field experiments, with associated modeling. EPA also agrees that the study’s 

conclusion cannot be viewed as evidence of imminent risk posed by CO2 geologic sequestration. EPA 

understands (and mentions in the NODA and request for comment) that the risk of CO2 leaking from 

deep storage is low for properly managed GS projects. However, because the leakage probability is 

not necessarily zero, the potential consequences of unlikely leakage events need to be understood and 

predictive capabilities need to be developed as a basis for risk and vulnerability assessment. 

Regarding “Geochemical model development”, EPA clarifies that the LBNL study by design was 

conducted to study the potential vulnerability of a wide range of typical and relevant aquifer types in 

the case of CO2 intrusion, in order to provide a foundation for further studies on groundwater quality 

concerns. While the overall results encompass a wide range of possible site specific conditions, the 

study was not meant to be site specific; rather the authors suggest the work should be followed by 

site-specific investigations, such as in situ experiments with associated modeling. 

Regarding “Mineral hosts controlling trace element solubility,” the authors of the LBNL study did not 

only assume that the trace element mineral hosts in potable water aquifers were the same as those 

123
found in coal and ore materials; they actually tested the hypothesis that they might be the same and 

present through comparison between the measured ion activity product and the calculated solubility 

product, i.e., by calculating the saturation index (SI) using chemical analyses of potable ground 

waters in the National Water Information System (NWIS) database. Modal values consistent with SI ≈ 

0 suggested their presence in many, but not all cases. This provides strong circumstantial evidence 

that the postulated mineral hosts are most likely present in the aquifer host rocks. In other cases, 

results, particularly with respect to Cd and Hg, were ambiguous, but even then, the number of 

alternative choices was significantly narrowed. The study therefore forms a sound basis for further 

independent investigations needed to verify the asserted hypothesis.

Regarding “Improvement of thermodynamic data,” it was not the intent, nor did the authors of the 

LBNL study state that they were attempting to “improve” the thermo¬dynamic data based on the 

findings from analyses of the ground waters from the NWIS database. However, for modeling 

purposes, LBNL did calibrate observed mineral solubilities to predict the impact of solubility 

perturbations due to changes in CO2 partial pressure, and subsequent modeling of arsenic and lead 

mobilization and transport, this being done, as noted, to ensure that the “...results should be viewed 

as relative changes to an assumed initial condition.” This calibration process, while common in 

hydrology, has proved to be controversial, and in a subsequent paper (Apps et al., 2009), the results 

have been presented both in calibrated form, and as a comparison between modeled predictions and 

field observations. Both sets are consistent within the uncertainties of the model, and the 

uncertainties and natural variability of field data from the NWIS database. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28103 

Comment: In addition, the NODA highlights research that has indicated that modeling CO2 

related water quality changes in groundwater aquifers results in an increased 

potential for the mobilization of arsenic above the drinking water maximum 

contaminant level (MCL). The NODA also states that, "Other trace elements, 

such as barium, cadmium, lead, antimony, and zinc, may also be mobilized in 

certain circumstances, but the majority of results did not show mobilization at 

levels exceeding the MCL or [action level] AL. (74 FR 44807)." This statement 

wrongly implies that any contamination below the MCL is not a concern for 

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drinking water utilities or for public health. This is emphatically not the 

case, as simply the presence of these contaminates would further degrade the 

suitability of an aquifer as a drinking water source. Furthermore, in the case 

of arsenic and lead, the maximum contaminant level goal is zero. 

Individual Response: EPA clarifies the MCLs, MCLGs, and ALs cited in the study were presented in 

LBNL’s work as a reference point for comparison purposes. The LBNL study makes no assertion about 

drinking water standards. EPA acknowledges that any increase in concentration of metals is 

undesirable to water utilities and the final rule requirements were established to maximize protection 

of USDWs. EPA clarifies that the LBNL study was conducted to study the potential vulnerability of 

representative and relevant aquifer types in the unlikely case of CO2 intrusion, in order to provide 

sound scientific information as a basis for further studies on groundwater quality concerns. 

EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (146.82(c)(3)). The data can help 

the Director determine the potential for geochemical reactions between the injectate (CO2) and the 

host geologic formations. For additional information on EPA’s approach to site characterization for GS 

wells, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28140 

Comment: 2. Lawrence Berkeley National Laboratory (LBNL) Studies The NODA discusses 

studies underway at LBNL to test the potential of CO2 to mobilize trace elements 

in potable groundwater. It notes that the "majority of results did not show 

mobilization" of trace elements such as barium, cadmium, lead, antimony, and 

zinc "at levels exceeding the MCL [maximum contaminant level] or AL[action 

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level]." [Footnote 9] It also notes that the results suggest that under certain 

conditions, arsenic levels could potentially exceed Federal drinking water 

standards when elevated CO2 levels are present. It concludes that while it "is 

important to emphasize that these studies looked at potential consequences of 

CO2 leakage into the USDW, not the likelihood of such leakage occurring. The 

goal of the UIC program and these regulations is to ensure that injectate does 

not contaminate USDWs in the first place." [Footnote 10] 

[Footnote 9] Id. at 44807. 

[Footnote 10] Id. 

It is of course important to understand potential effects on USDWs should 

migration occur; however, it is equally important to retain the context. Proper 

site characterization is the most important risk management tool for GS. 

Migration of CO2 from the receiving formation of properly sited and managed 

projects is extremely unlikely. The Intergovernmental Panel on Climate Change 

(IPCC) concluded in 2005 that the fraction of CO2 retained in "appropriately 

selected and managed geological reservoirs" is likely to exceed 99 percent over 

1,000 years.[Footnote 11] Regardless, it is notable that even in the context 

of this "worst case scenario," the majority of results did not demonstrate 

potentially harmful impacts to USDWs. 

[Footnote 11] See IPCC, Special Report on Carbon Dioxide Capture and Storage, 

section 1.6.3, available at, 

http://www.ipcc.ch/pdf/special-reports/srccs/srccs_wholereport.pdf. 

Individual Response: EPA acknowledges that the LBNL study does not consider the risk of a leak 

from a sequestration basin occurring, but only the results if leakage did occur. EPA reaffirms that the 

intent of the UIC program is to prevent such leaks from occurring in the first place. 

EPA clarifies that site-specific data are necessary to understand the potential geochemical reactions at 

a GS site. For this reason, all GS project owner or operators must submit detailed, site-specific 

information about a proposed GS site, including information on the porosity, permeability, mineralogy, 

and geochemistry of the targeted injection and confining zones as well as all USDWs within the Area of 

Review. Operators must also present information on the compatibility of the CO2 stream with fluids in 

the injection zone and minerals in the injection and confining zones (146.82(c)(3)). The data can help 

the Director determine the potential for geochemical reactions between the injectate (CO2) and the 

host geologic formations. For additional information on EPA’s approach to site characterization for GS 

wells, see the responses to comments on the proposed rule in the rulemaking docket. 

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EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28298 

Comment: III. Research, Data Analysis and Findings 

A. The Lawrence Berkeley National Laboratory Study of Ground Water Quality 

Changes Related to the Mobilization of Trace Elements Demonstrates the Need that 

EPA model the Regulations on the Precautionary Principle. 

The Lawrence Berkeley National Lab (LBNL) used a comprehensive computational 

model to evaluate the potential impact of CO2 leaking from deep geologic 

sequestration sites on the concentrations of trace elements in potable ground 

waters. 74 Fed. Reg. at 44,807. "Results of this modeling obtained for typical 

aquifers under reducing conditions indicate that arsenic could potentially 

exceed Federal drinking water standards at elevated CO2 concentrations (40 CFR 

141.62 (b)(16))." Id. 

The results of this study stress the need for continuous monitoring and 

reporting, as is currently required under the proposed rules. The purpose of the 

Safe Drinking Water Act is to protect "underground sources of drinking of 

water." Since it is documented that CO2 leakages could lead to a violation of 

the drinking water standards and threaten public health, the EPA should ensure 

that the final rules continue to require continuous monitoring and reporting to 

ensure that USDWs are protected. 

Individual Response: EPA agrees that monitoring is an important component of the UIC program 

and the final GS regulation contains comprehensive site characterization, construction, monitoring 

(e.g., ground water monitoring and CO2 plume and pressure front to verify that the injectate is safely 

confined in the target formation) and site closure requirements to ensure that USDWs are not 

endangered. For additional information about EPA’s approach to monitoring and reporting for GS 

projects, see the responses to comments on the proposed rule in the rulemaking docket. 

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EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28316 

Comment: The NODA also discusses studies underway at Lawrence Berkeley National 

Laboratory to test the potential for carbon to mobilize trace elements in 

potable groundwater. These studies looked at the potential consequences of 

carbon leakage into USDW but not the likelihood of the occurrence of such 

leakages. Migration of carbon from properly sited and managed projects is 

extremely unlikely. The Inter-Governmental Panel on Climate Change concluded in 

2005 that a fraction of carbon retained in appropriately selected and managed 

geologic reservoirs is likely to exceed 99 percent over 1,000 years. EEI agrees 

that it's important to understand the potential impacts on USDW if migration 

occurs. However, the most important risk management tool for GS is proper site 

characterization. 

Individual Response: It is understood (and mentioned in the NODA) that the risk of CO2 leaking 

from deep storage is low for properly managed GS projects. However, the potential consequences of 

unlikely leakage events need to be understood and predictive capabilities need to be developed as a 

basis for risk and vulnerability assessment. 

EPA agrees that proper site characterization is necessary to understand the potential geochemical 

reactions at a GS site. For this reason, all GS project owners or operators must submit detailed, sitespecific information about a proposed GS site, including information on the porosity, permeability, 

mineralogy, and geochemistry of the targeted injection and confining zones as well as all USDWs 

within the Area of Review. Operators must also present information on the compatibility of the CO2 

stream with fluids in the injection zone and minerals in the injection and confining zones 

(146.82(c)(3)). The data can help the Director determine the potential for geochemical reactions 

between the injectate (CO2) and the host geologic formations. For additional information on EPA’s 

approach to site characterization for GS wells, see the responses to comments on the proposed rule in 

the rulemaking docket.

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In addition, the Agency will, every six years, collect and review data on GS projects and research to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2220 2.2.2. Basin-Scale Hydrologic Impacts of CO2 Storage (seeking 

comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27863 

Comment: 3. EPA requests comments on parts of the FR proposed rule 

a. Birkholzer, J.T., Q. Zhou, and C.F. Tsang. 2009. Large-Scale Impact of CO2 

Storage in Deep Saline Aquifers: A Sensitivity Study on the Pressure Response in 

Stratified Systems. International Journal of Greenhouse Gas Control, 3(2), 

181-194 

This report demonstrates a simulation program can be written, but since 

the simulation results were not correlated with physical measurements from an 

actual reservoir, the model and results are unsubstantiated. 

129
Individual Response: The paper described in the NODA is, by design, a generic modeling exercise 

with the objective of studying parameters and processes that are important for large-scale pressure 

changes. A wide range of parameter sensitivity cases was studied, with the parameter ranges tied to 

the range of conditions found in actual reservoirs that are representative of potential GS sites. EPA 

clarifies that the purpose of this study was not to model an actual reservoir; rather it was to provide a 

better understanding of the potential impact of industrial-scale CO2 injection on regional ground water 

systems for a wide range of geological conditions. While generic studies such as this one provide value 

and demonstrate that the necessary modeling technology is available to support for such evaluations, 

EPA recognizes that each GS site is unique, and for this reason, the GS rule requires a detailed sitespecific evaluation of local geologic conditions (§146.82) and modeling to delineate the AoR 

(§146.84). For additional information regarding EPA’s requirements for site characterization for GS 

projects, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28188 

Comment: 2. We believe that "Far Field" pressure is important to understand, but need not 

be a concern with proper and effective injection site characterization, which in 

this case would consider pressure effects more remote from the injection site. A 

practical approach should be able to monitor plume pressure migration and alter 

the operation if appropriate. This is an area where more experience is needed 

and the rule should be written to foster gaining this experience. 

Individual Response: EPA agrees that proper site characterization, together with predictive 

modeling and far-field pressure monitoring are important components of siting and managing GS 

projects. The final GS rule requires a detailed site-specific evaluation of local geologic conditions 

(§146.82) and modeling to delineate the AoR based on the detailed geologic data collected during the 

site characterization process (§146.84). Monitoring of the plume and the pressure front are required 

throughout the operational phase (§146.90). One goal of the siting and AoR delineation process is to 

identify the potential for pressure changes that may cause unacceptable fluid movement, even if they 

occur far from the injection well. If such pressure increases were predicted at levels that could 

potentially endanger USDWs, a GS site would not be permitted. If far field pressures were to increase 

130
above predicted levels, pressure management schemes via brine extraction from the storage reservoir 

may be an appropriate remedial action; however prevention of such impacts is the focus of the GS 

rule. For additional information regarding EPA’s requirements for AoR delineation and monitoring for 

GS projects, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28194 

Comment: 9. We appreciate the modeling LBNL conducted of a hypothetical sedimentary basin 

with several projects injecting high aggregate and cumulative quantities of CO2 

annually over an extended period. The results, though hypothetical, argue in 

favor of case-specific consideration of: (a) large volume injections; and (b) 

defendable close proximity between injection points. That is local conditions 

may accommodate higher than normal injection rates and closer proximity to other 

injection activity. 

Specifically, the rule should be finalized with language that allows 

consideration of injection projects that, based on modeling, that show the 

injection horizon to have characteristics favorable to high-volume injection 

and/or relatively close proximity injection sites. Injection pressure effects, 

plume migration rate, and avoidance of fracture pressure would be some of the 

considerations. 

10. As noted earlier, we support consideration of the potential effects of "far 

field" pressure build up in siting criteria to ensure the integrity of the 

injection horizon remote from the injection location. The rule should allow case 

specific determination of appropriate injection quantities and conditions. 

Individual Response: The LBNL modeling study of the hypothetical basin was not meant to provide 

arguments in favor of large-volume projects and close proximity between sites. Rather, LBNL started 

with the assumption that in order to have GS make a contribution to climate change mitigation, large 

volumes of CO2 may have to be injected and individual projects may have to be in proximity to each 

131
other. The example study cited assumes that one third of the current annual emissions from large 

stationary sources in the hypothetical sedimentary basin are being captured and stored.

EPA agrees with the commenter that the determination of appropriate injection quantities and 

conditions is important, and the GS rule requires that the AoR delineation account for the types of 

site-specific circumstances the commenter describes. The rule requires that the owners or operators of 

GS wells delineate the AoR for GS sites using computational fluid flow models appropriate to the sitespecific conditions and injection regime (§146.84). These site-specific conditions include the injectivity 

and storage capacity to allow the appropriate volume of injection for the particular formation without 

initiating or propagating fractures in the confining zone(s) and creating risk to any ground water 

resources due to any effects of hydraulic perturbations. For additional information regarding EPA’s 

requirements for AoR delineation for GS projects, see the responses to comments on the proposed 

rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28209 

Comment: Also, while the LBNL scenario described in "Sedimentary Basin Case Study" 

represents state of the art modeling of large scale deployment of CCS in a 

basin, it is not at all clear how relevant this work is to the proposed Class VI 

rule as the scenario envisioned seems to be precluded by the requirements to 

receive and retain a Class VI injection permit spelled out in the July 2008 

draft rule. 

The "Sedimentary Basin Case Study" scenario states that 20 facilities each of which 

inject 5MtCO2 per year are located within this hypothetical basin (FIGURE 8). 

Assuming that all 20 sources are power plants, they would each be the equivalent 

of a 1000 MW IGCC+CCS. It is difficult to imagine a scenario in which 20 GW of 

electrical generating capacity would come on line simultaneously {FOOTNOTE 6} in 

just one relatively small region of the United States {FOOTNOTE 7}. 

FIGURE 8: BOUNDARY OF THE DEVELOPED BASIN-SCALE (Taken from BIRKHOLZER, J.T., Q. 

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ZHOU, K. ZHANG, P. JORDAN, J. RUTQVIST, C.-F. TSANG (2008): Research Project on 

CO2 Geological Storage and Groundwater Resources: Large-scale Hydrogeological 

Evaluation and Impact on Groundwater Systems, Annual Report October 1, 2007 to 

September 30, 2008, Report, Lawrence Berkeley National Laboratory, Berkeley, CA, 

USA.) 

{SEE PG 4 OF EPA-HQ-OW-2008-0390-0334.pdf for IMAGE OF FIGURE 8} 

{FOOTNOTE 6} See for example, MA Wise and JJ Dooley. 2009. "The Value of PostCombustion Carbon Dioxide Capture and Storage Technologies in a World with 

Uncertain Greenhouse Gas Emissions Constraints." International Journal of 

Greenhouse Gas Control. Volume 3, Issue 1. (2009), pp. 39-48 DOI: 

10.1016/j.ijggc.2008.06.012 which forecasts CCS deployment at this scale but 

spread out across the entire ECAR region and spread out across nearly half of a 

century. 

{FOOTNOTE 7} It is important to stress how unrealistic this scenario is for the 

purpose of informing the draft Class VI proposal. A back of the envelope 

calculation involving line of sight limitations imposed by the curvature of the 

Earth suggests that if the cooling towers at these 20 facilities were 100m tall 

or higher one could literally see some of the other plants. Therefore, it is 

extremely difficult to envision how these 20 units could all come on line 

simultaneously without anyone recognizing how closely spaced they are and taking 

action (most likely via alterations to some of the pending Class VI injection 

permits) to avoid the scenario modeled by LBNL from ever materializing. 

More importantly, if the assumption is that these 20 facilities do not come on 

line simultaneously but rather phase in over time, then the July 2008 draft 

Class VI CO2 Storage rule would seem to prevent this situation from occurring as 

the rule requires that new injection well applicants take into account projects 

that have already been permitted when preparing their permit application. It is 

difficult to see how a situation could be allowed to develop where 20 very large 

facilities could be permitted so near each other to start at the same time, 

without raising flags to regulators to request additional information from the 

applicants on CO2 plume movement and pressure build up, and request subsequent 

potential re-evaluation of initial project AORs, pressure effects and potential 

impacts to drinking water. While the value of understanding near- and far-field 

pressure effects for projects located so close together is undisputed, the 

potential for so many projects being inadvertently permitted in the same area 

alone is so far-fetched that the scenario clearly can’t be put forth as a real 

possibility, and perhaps EPA could do a better job in communicating that this 

scenario is not intended to represent future reality. As an academic exercise to 

133
educate the technical community and inform requirements within the proposed rule 

to ensure that cumulative effects across multiple projects within the same 

geographic area, however, this work is important. 

More importantly however, if the EPA promulgates the rules as drafted and has 

the resources to enforce the rules, these basin scale concerns will be managed 

proactively, and pressures can be maintained within acceptable ranges. This is 

the point that should have been clearly communicated via the presentation of 

this modeling work. 

Individual Response: EPA acknowledges that 20 projects coming online simultaneously is not a 

realistic assumption, rather it is a modeling simplification. However, even if the 20 projects were 

phased over a 10-year period (and assuming a 50-year operational life time), there would still be a 

40-year period with all 20 projects in operation, and the basic results obtained from the modeled 

scenario would not significantly change if a phased scenario had been assumed. Considering the 

existing power plants and other large stationary CO2 emitters in the example region, with a total 

annual emission of 300 Mt CO2, EPA believes that the modeling scenario is reasonable.

The sedimentary basin case cited in Birkholzer et al. (2008b) assumes that one third of the current 

annual emissions from large stationary sources in the example area are being captured and stored. 

LBNL started with the assumption that in order to have GS make a contribution to climate change 

mitigation, large volumes of CO2 would have to be injected, representing a significant fraction of the 

CO2 generated from stationary sources within a given area. 

Given that large volumes from several facilities would need to be sequestered in a given area, it may 

be unrealistic to assume that storage sites can be placed so far from each other that their pressure 

envelopes would never overlap. The spatial pattern of GS projects used in LBNL’s work was developed 

by placing the 20 storage sites into the center of the example basin where the geological conditions 

were most favorable for CO2 storage (i.e., sufficient thickness and depth of storage reservoir, distance 

from natural gas storage fields in operation, large distance to transmissive faults). In other words, the 

assumption was made that CO2 would be pipelined from stationary emitters located in areas where 

geologic conditions are less favorable (i.e., too shallow for injection of supercritical CO2, too deep for 

economic injection and not permeable enough). Thus, the hypothetical GS scenario is not a scenario of 

inadvertent permitting without recognizing close proximity of several GS sites, but rather close 

proximity is assumed to be necessary in certain cases and potential impacts thereof are being 

evaluated. Furthermore, while an average distance about 30 km is assumed in LBNL’s scenario, 

pressure interference between individual storage projects could be expected even if this distance was 

doubled or even tripled, while the far-field pressure perturbation away from the basin center would be 

similar.

134
EPA agrees that proactive management of basin scale concerns to maintain pressures within 

acceptable ranges is important, and encourages owners or operators and permitting authorities to 

communicate planned GS activities to maximize coordination and minimize pressure interference. If a 

permit applicant (or the permitting authority) is aware of pending GS projects near a proposed well, 

the AoR delineation performed pursuant to §146.84 should account for the impacts of multiple owners 

and operators injecting within a single basin. EPA anticipates that, where multiple operators are 

involved, the Director would not approve modeling that does not account for changes that may result 

from all injection operations. As the commenter points out, the proximity of injection sites to each 

other and the relative timing of each injection operation might indicate a possible increase in risk for 

the containment of the total CO2 and/or the effects of hydraulic perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the 

permitting of the newer GS project would have considered the presence of an existing GS project. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert J. Finley 

Commenter Organization: Illinois State Geological Survey 

EPA Letter ID: 0337 

EPA Comment ID: 28002 

Comment: Basin-scale modeling can be informative with respect to issues that may be faced 

in the future with multiple injection projects using the same storage reservoir 

in a given basin. The work of Birkholzer, Zhou and others (referred to as the 

authors herein) is illustrative in this regard in that it utilizes an actual but 

not yet fully characterized basin framework. In assessing the pressure field and 

brine migration potential developed as part of this work, it has to be clearly 

noted, however, that a spacially concentrated and certainly arbitrary injection 

scenario was required to generate the perturbations resulting in the model 

outcomes. The scenario was designed to create these perturbations and in itself 

is a far-end member of the range of scenarios that might be utilized. Certain 

assumptions also had to be made regarding increases in seal permeability to 

generate the model results and these assumptions need significant refinement. As 

such, this is acceptable as a modeling exercise and as a guide to future studies 

135
but not as a predictable outcome or even a generalized outcome, and in fact the 

authors call for further strategies for pressure monitoring and the improvement 

of predictive models. Although the authors highlight far-field impacts, it is 

premature for U.S. EPA to consider any basin-scale mandates other than intensive 

data collection and assessment, including support for improvement in basin-scale 

simulation models that are indicators of large-scale hydrologic impacts. This 

work must be taken as an indicator of a research need, given the hypothetical 

concentration of twenty large storage projects in a limited area, not of the 

need for developing any specific basin-scale regulations as part of the current 

Class VI development process. The latter approach would be counterproductive in 

that it may negate: (1) the development of multiple initial projects essential 

to more definitively define the very safeguards that groundwater protection 

strategies are designed to achieve, and (2) suppress the realization of more 

appropriate injection scenarios (rate, period, and placement) that would yield 

more realistic results than the inputs selected for the author’s modeling. 

Support of this position is found in the authors work. They cite a Darcy flow 

velocity across the top model boundary, averaged over the model domain, of 0.47 

mm/year at 50 years of injection and an average Darcy velocity across the 

lateral boundaries of about half that value. The authors then go on to state: 

"The lateral migration distances of saline water associated with these boundary 

flows do not constitute a concern for the groundwater resources in overlying 

aquifers or neighboring basins." The authors also note that current groundwater 

withdrawal practices in the northern Illinois Basin are pulling saline water 

toward some water wells, and that "these impacts dwarf the predicted 

environmental consequences of the hypothetical CO2 storage scenario studied...". 

New data are being developed as a result of currently funded sequestration 

deployment testing. An example of the impacts of incompletely known chosen 

parameters can be seen in the discussion of hydraulic diffusivity. Recent work 

in the Illinois Basin indicates that the porosity value chosen for the modeling 

is low relative to higher porosity values obtained from recent drilling in the 

model injection area, thus recent data would tend to reduce the pressureaffected region outside of the injection area. The authors narrate a sensitivity 

case that, they state, would reduce the region from 190 km to only 60 km in 

radius, but would also be dependent on lower permeability and greater 

compressibility, as well as the higher porosity. Again, initial storage project 

development must occur to better define key parameters. Further, it is also 

important to recognize that the discussion of the capacity assessments for the 

basin compared to the 50-year, 5,000 Mt perturbation in the model confuses the 

sequestration resource with basin capacity and the numbers in the DOE atlas are 

resources, not capacity. There is no expectation that the early DOE resource 

assessments would represent actual capacity. The authors statement that these 

136
resource estimates are subject to "an implicit assumption that the storage 

capacity is not constrained by pressure buildup and brine migration..." is 

incorrect, and researchers involved with creating these estimates would be 

unlikely to agree with this assumption. These are not undue criticisms of the 

work, simply an indication that definitions need to be refined and common 

terminology needs to become more widespread. The authors conclude that in a 

basin with multiple storage sites, industrial-scale storage projects are needed 

to supply valuable data "to reliably estimate the expected pressure impacts of 

later projects". That is certainly where we must go to answer key questions 

while acknowledging that the state of understanding of modeling basin-scale 

sequestration impacts is in its early stages and is premature for rule making at 

this time. 

Individual Response: EPA agrees with the commenter regarding the need for comprehensive site 

characterization and data review of large-scale saline formations. The final GS rule requires owners or 

operators of GS wells to delineate the AoR for GS sites using computational fluid flow models designed 

for the specific site conditions and injection regime (e.g., current injection activities). Periodic 

revisions and recalibrations of the models must be conducted as described in the approved AoR and 

corrective action plan required at 146.84. The final rule also requires monitoring of the plume and the 

pressure front throughout the injection phase (146.90). For additional information regarding EPA’s 

requirements for AoR delineation for GS projects, see the responses to comments on the proposed 

rule in the rulemaking docket.

EPA acknowledges the need for improvement/validation of predictive models before considering basinscale mandates, and will continue to collect and review data on early GS projects as part of its 

adaptive rulemaking approach. EPA recognizes that inter-state and even international cooperation 

may be necessary where multiple injection operations may interact, but has no plans or authority to 

develop a basin-wide regulatory process. The final GS rule focuses on permitting of individual GS wells 

and therefore does not include requirements for basin-scale evaluations. EPA notes, however that the 

GS rule, at §146.82(b), requires that the Director notify representatives of all states, tribes, and 

territories in the AoR to inform them of the permit application and offer them an opportunity to be 

involved in any relevant activities, such as development of the required project-specific plans.

Regarding the comment that the paper presents a spatially concentrated and arbitrary injection 

scenario, EPA notes that, considering the large volumes that need to be sequestered to make a 

contribution to climate change mitigation and the volumes that are produced from large stationary 

sources, it may be unrealistic to assume that storage sites can be placed so far from each other that 

their pressure envelopes would never overlap. The spatial pattern of GS projects used in LBNL’s work 

was developed by placing the 20 storage sites into the center area of the example basin where the 

geological conditions were most favorable for CO2 storage.

137
Regarding the assumption about seal permeability, the base simulation case in the basin-scale model 

used vertical permeability of seal of 1.0 × 10-18 m2. A sensitivity case was studied in Birkholzer et al. 

(2009) assuming a seal permeability of 1.0 × 10-20 m2. A higher seal permeability allows for 

pressure attenuation in the storage formation caused by slow diffuse brine migration into the seals. 

The two simulation cases reflect the range of seal properties available for the example basin, from 

core scale measurements and regional scale estimates (Zhou et al., 2009).

Regarding capacity, while EPA acknowledges differences in terminology (e.g., the resource estimates 

provided in USDOE (2008) correspond to effective capacities in the definition given in CSLF (2008) 

and the USDOE capacity estimates correspond to the CSLF practical capacities) the point Birkholzer 

and Zhou (2009) are trying to make is that the practice of estimating resource (or effective capacity) 

via efficiency factors does not include pressure and brine migration constraints. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

EPA Letter ID: 0339 

EPA Comment ID: 28009 

Comment: SWRCB Comment #1 on: "2. Basin-Scale Hydrologic Impact of CO2 Storage" 

The Lawrence Berkeley National Laboratory (LBNL) modeled an area, 570 kilometers 

(km) by 550 km, with 20 carbon dioxide (CO2) injection points at 5 million tons 

of CO2 per year, total 100 mln. tons per year. (Humans breathing about 6- 

million tons of CO2/day, which equates to over 2-billion tons/year). To store 

human CO2 alone would require over 20 these areas. The LBNL simulation 

indicated that the subsurface pressure change induced by injection extends over 

area of 400 km2 after 50 years. Model's assumption was that there was an 

extensive confining layer over the entire CO2 sequestration area. A specific 

code was used for simulation was developed for modeling of water or solute 

migration in porous media, not for subsurface gas migration. 

Findings: 

Confining layer(s) for fluids (water or oil) may not confine CO2 -type gases. 

138
CO2 dissolved in water creates carbonic acid. Carbonic acid is corrosive to 

several types of rocks which will dissolve rock. This will increase porosity by 

enlarging existing rock fractures, which creates a conduit for CO2 gases to 

escape from the repository formation into the atmosphere. 

Injection of CO2 into exhausted oil and natural gas bearing formations will have 

high potential for CO2 to migrate back to the atmosphere. Additionally, the 

formation has been perforated by thousands of oil and natural gas wells 

(abandoned or not) allowing CO2 to escape to the atmosphere. 

Future tectonic events (earthquakes) will likely cause catastrophic release of 

CO2 into drinking or potentially drinking water aquifers and the atmosphere. 

Individual Response: In response to the commenter’s criticism of the specific code used in the 

study, EPA clarifies that the TOUGH2 model used is a general purpose simulation program designed 

for multi-dimensional fluid and heat flows of multiphase and multi-component fluid mixtures in porous 

and fractured media. TOUGH2/ECO2N simulates water and solute transport together with gas 

migration of supercritical CO2. 

EPA agrees that the factors cited by the commenter are important considerations. The GS rule 

requires geologic site characterization to verify the presence of adequate confining layers, help predict 

geochemical reactions which can lead to dissolution and/or precipitation of minerals, and identify the 

presence of seismic sources and faults or fractures to address these concerns (§146.82). 

EPA acknowledges that induced seismicity is a risk that may be associated with GS but maintains that 

the risk is low (IPCC, 2005). The GS rule contains several requirements to address seismic risk. First, 

as part of the site characterization process, owners or operators must submit information about the 

seismic history of and seismic sources near a proposed GS site, data on known or suspected faults in 

the AoR, geomechanical information on fractures, stress, ductility, rock strength, and in situ fluid 

pressures within the confining zone (§146.82(a)(3)). Owners or operators must also conduct 

extensive monitoring to detect possible CO2 movement from the injection zone (§146.90). For 

additional information regarding EPA’s requirements for AoR delineation and monitoring of GS 

projects, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

139
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28042 

Comment: Basin Scale Impacts of CO2 Injection 

EPA states that the LBNL study of Basin- Scale impacts "illustrates the 

importance of basin-scale evaluation of reservoir pressures and far-field 

pressures resulting from CO2 injection" (NODA, p. 44808). API cautions EPA 

against basing regulations or permit requirements on the outcomes of this due to 

the constraints of the model. Three examples of modeling assumptions/design 

impacting the results stand out. First, the model assumes lateral homogeneity 

of all stratigraphic units. Permeability in the Eau Claire Shale top seal may 

vary considerably in a lateral sense at regional scales but in the model, the 

permeability is uniform. Second, the compressibility values of the Mount Simon 

that were used are less than published values. Increasing compressibility would 

reduce the predicted pressure buildup. Third, it was noted in Juanes, 2006, that 

in general, coarse grids overestimate CO2 movement and capillary 

trapping.[Footnote 9] The adaptive gridding approach used in the Illinois Basin 

model uses progressively larger grid cells away from the injection area. The 

largest cells near the edge of the basin are 10 x 10 km, and the maximum 

thickness of any grid block was set to 10 m. The high aspect ratio and large 

size of these cells may introduce significant numerical dispersion in the model 

results. Conclusions based on the modeled brine flow out of the basin and far 

field pressure effects should be considered qualitative at best, and are likely 

conservative given the constraints of the model. 

[Footnote 8]: Arnold, T., Bahr, J., and Fantucci, R., 1996, Paleohydrogeology of 

the Upper Mississippi Valley Zinc-Lead District, in Sangster, D. F., ed., 

Carbonate-Hosted Lead-Zinc Deposits, Society of Economic Geologists Special 

Publication Number 4, p. 378-389. 

[Footnote 9]: Juanes, R., Spiteri, E.J., Orr, F.M., and Blunt, M.J., 2006, 

Impact of relative permeability hysteresis on geological CO2 storage, Water 

Resource Research, Vol. 42, No. 12, W12418. 

Nonetheless, contrary to EPA's interpretation of the results - that "basin-wide 

pressure influences can be large" (NODA, p. 44808)- the modeled brine out-flow 

and far field pressure effects (an increase of 0.5 bar) are very small, and 

140
would likely have been even lower if the model had included lateral 

heterogeneities in permeability and porosity and used a higher compressibility. 

The predicted pressure perturbations are so minor that they would likely not be 

accurately distinguished from normal variation in routine pressure data 

collection. 

Moreover, basin-wide modeling is not applicable to Area of Review 

determinations. While basin-scale modeling may be informative, responsibility 

for this undertaking falls outside the scope of individual project permitting. 

Furthermore, adaptive rule-making will allow for adjustments to encompass 

multiple projects in the same basin if and when needed in the future. 

Individual Response: EPA acknowledges that basin-scale predictions are uncertain due to the limited 

information generally available for large subsurface volumes. While the example modeling study cited 

in the NODA is based on the best information available, significant prediction uncertainty remains and 

results should be viewed as illustrative, as acknowledged in Birkholzer and Zhou (2009). While generic 

studies such as this one provide value and demonstrate that the necessary modeling technology is 

available to support for such evaluations, EPA recognizes that each GS site is unique, and for this 

reason, the GS rule requires a detailed site-specific evaluation of local geologic conditions (§146.82) 

and modeling to delineate the AoR (§146.84).

Regarding the comment that basin-wide modeling is not applicable to AoR determinations, EPA 

clarifies that the purpose of this study was not to model an actual reservoir; rather it was to provide a 

better understanding of the potential impact of industrial-scale CO2 injection on regional ground water 

systems for a wide range of geological conditions. EPA will look at basin-scale impacts as part of its 

adaptive rulemaking approach. 

Regarding the comment on “lateral homogeneity” in the Eau Claire Shale top seal, EPA clarifies that 

the seal data were too sparse to reliably estimate lateral heterogeneity. The impact of seal 

permeability was evaluated in sensitivity cases assuming two different (homogeneous) seal 

permeability values (Birkholzer and Zhou, 2009). The general outcome of the simulation study (i.e., 

size of the pressure-affected region) was not strongly influenced by the parameter choice.

The model choice for pore compressibility is discussed in detail in Zhou et al. (2009), and is believed 

to be well constrained. The pore compressibility used in the model was obtained through a pumping 

test in central Illinois, at a depth of 2000 m just north of the assumed injection area. Additional 

pumping tests available in shallower parts of the storage reservoir corroborate the chosen value. 

These values used in the model are within the range of pore compressibility reported for wellconsolidated sandstones at in situ effective stresses representative of Mt. Simon. 

141
Regarding “gridding and numerical dispersion,” numerical dispersion is a concern for solute transport 

with sharp interfaces (advection-dispersion equation) and/or for multi-phase transport. For single 

phase flow, such as ground water flow and pressure perturbation, there is no numerical dispersion, 

only the possibility of small approximation errors. Thus, there may be some gridding effect and 

numerical dispersion when simulating CO2 movement and capillary trapping, but this effect is small 

because the discretization is refined in the vicinity of each CO2 plume. As to the far-field pressure 

response, numerical dispersion is not an issue. 

Regarding the comment on “far-field pressure effects,” the 0.5-bar pressure threshold was used as an 

example illustrating the enormous size of the region affected by some pressure perturbation; it was 

not meant to imply that a 0.5-bar pressure increase is a significant threat. However, even a more 

significant 5-bar threshold would still result in a large pressure-affected region. It is pointed out in 

Birkholzer and Zhou (2009) that the modeled brine migration within the reservoir and into/through 

the seals would not constitute a concern for ground water resources. Pressure perturbation, however, 

could become a concern if deep saline water was pushed upward into overlying fresh water aquifers 

via potentially existing localized pathways, which were not included in the model. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28081 

Comment: Page 44808: "EPA believes that the example studied by LBNL illustrates the 

importance of basin-scale evaluation of reservoir pressures and far-field 

pressures resulting from CO2 injection." 

EPRI COMMENT#4: EPRI agrees that pressure interference from multiple projects in 

a basin may have an impact on near and far-field pressures. This suggests that 

basin-scale management where multiple projects are planned would be beneficial. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

142
encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to §146.84 should account for the impacts of multiple owners and operators injecting within 

a single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the 

permitting of the newer GS project would have considered the presence of an existing project. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27939 

Comment: Basin-Scale Hydrologic Impacts of CO2 Storage 

The recent LBNL modeling studies on basin-scale carbon dioxide storage cited in 

the NODA indicate that pressure changes could propagate as far away as 124 miles 

(200 kilometers) from the CO2 injection area. This suggests that the area of 

review must be extended over a much larger area than previously anticipated. 

AWWA supports the requirement that basin-scale hydrologic impacts of CO2 storage 

on reservoir pressure pressures and far-field pressures be addressed in the GS 

permitting process. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

143
encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to §146.84 should account for the impacts of multiple owners and operators injecting within 

a single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the 

permitting of the newer GS project would have considered the presence of an existing project. For 

additional information regarding EPA’s requirements for AoR delineation and monitoring of GS 

projects, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28114 

Comment: 1. Regarding the NODA summary of LBNL studies on "Basin-Scale Hydrologic Impacts 

of CO2 Storage', we feel that a clarification of the results of this preliminary 

simulation and their implications are needed. In particular, it was noted that, a 

pressure increase of 0.5 bar might be expected at the distal extent of the 

regional aquifer (200km from the core injection area). The next sentence states 

that "...basin-wide pressure influences can be large." This implies that 0.5-bar 

(~0.5 atm) pressure elevation at the perimeter of the basin is "large". Whereas 

we recognize that pressure perturbations will be significant in the core 

injection area (especially where pressure fields intersect), a 0.5-bar increase 

in pressure at the basin perimeter is not significant in terms of threatening 

containment. 

144
Individual Response: EPA clarifies that in the study the 0.5-bar pressure threshold was used as an 

example illustrating the enormous size of the region affected by some pressure perturbation; it was 

not meant to imply that a 0.5-bar pressure increase is a significant threat. However, even a more 

significant 5-bar threshold would still result in a large pressure-affected region. The concern about 

pressure perturbation is that deep saline water could be pushed upward into overlying freshwater

aquifers via potentially existing localized pathways. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28172 

Comment: 3. LBNL Study of Basin-Scale Hydrologic Impacts of CO2 Sequestration 

The results of the 2008 LBNL study of basin-scale hydrologic impacts of CO2 

sequestration [FOOTNOTE 9] highlighted in the NODA, [FOOTNOTE 10] demonstrate 

the potential for interference of far-field pressures in large-scale GS 

deployment. Although we do not interpret the interference and pressure effects 

described in the study as "significant" compared to injection or formation 

pressures, these results underscore the importance of sound basin-scale 

management practices, and the need for a non- interference principle to be 

adhered to during the early years of GS activity, until greater proficiency in 

basin-scale management is gained. [FOOTNOTE 11] 

FOOTNOTE 9 - Not "storage" - LBNL did not assume that the CO2 could or will be 

released in the future. 

FOOTNOTE 10 - 74 Fed. Reg. 44808. 

FOOTNOTE 11 - Also refer to Multi-Stakeholder Group letter of May14. 2009, which 

supported the inclusion of a non-interference principle. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

145
management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to §146.84 should account for the impacts of multiple owners and operators injecting within 

a single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the

permitting of the newer GS project would have considered the presence of an project. For additional 

information regarding EPA’s requirements for AoR delineation for GS projects, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28097 

Comment: Basin Scale Impacts of CO2 Injection 

EPA states that the LBNL study of Basin-Scale impacts "illustrates the 

importance of basin-scale evaluation of reservoir pressures and far-field 

pressures resulting from CO2 injection" (NODA, p. 44808). APC would caution EPA 

from basing regulations or permit requirements on the outcomes of the study due 

to the constraints of the model and assumptions. In addition the state of 

understanding the modeling of basin-scale CO2 sequestration impacts is in its 

early stages and thus is not appropriate for use in rulemaking at this time. 

Conclusions based on the modeled brine flow out of the basin and far field 

pressure effects should be considered tentative at best given the significant 

(and potentially incorrect) assumptions made in the model. This is particularly 

true given that the modeled brine out-flow and far field pressure effects are 

146
very small, and would not likely have been observed if the model had included 

lateral heterogeneities in permeability and porosity and higher compressibility. 

Under the proposed rule, basin-wide model results are not applicable to Area of 

Review decisions for individual site selection. The multi-stakeholder group 

recommendations dated May 14, 2009, provide an approach for handling multiproject basins where pressures fronts may intersect and influence. Adaptive 

rule-making could allow for adjustments to encompass multiproject scenarios in 

the same basin if needed in the future. However, it raises the question of who 

would be responsible for doing basin-wide analysis and at what point should it 

be conducted. 

Individual Response: The results of the modeling study did not cause EPA to change any aspects of 

the site characterization or AoR delineation requirements for GS projects. The final GS rule focuses on 

permitting of individual GS wells and therefore does not include requirements for basin-scale 

evaluations. However, EPA agrees that proactive management of basin scale concerns to maintain 

pressures within acceptable ranges is important, and encourages owners or operators and permitting 

authorities to communicate planned GS activities to maximize coordination and minimize pressure 

interference. If a permit applicant (or the permitting authority) is aware of pending GS projects near a 

proposed well, the AoR delineation performed pursuant to §146.84 should account for the impacts of 

multiple owners and operators injecting within a single basin. EPA anticipates that, where multiple 

operators are involved, the Director would not approve modeling that does not account for changes 

that may result from all injection operations. The proximity of injection sites to each other and the 

relative timing of each injection operation might indicate a possible increase in risk for the 

containment of the total CO2 and/or the effects of hydraulic perturbations and brine displacement. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket.

Regarding the model assumptions, EPA acknowledges that basin-scale predictions are uncertain due to 

the limited information generally available for large subsurface volumes. While the example modeling 

study cited in the NODA and Request for Comment, and its underlying assumptions, are based on the 

best information available, significant prediction uncertainty remains and results should be viewed as 

illustrative, as acknowledged in Birkholzer and Zhou (2009). EPA clarifies, however, that the model 

choice for pore compressibility is discussed in detail in Zhou et al. (2009), and is believed to be well 

constrained. The pore compressibility used in the model was obtained through a pumping test in 

central Illinois, at a depth of 2000 m just north of the assumed injection area. Additional pumping 

tests available in shallower parts of the storage reservoir corroborate the chosen value. These values 

used in the model are within the range of pore compressibility reported for well-consolidated 

sandstones at in situ effective stresses representative of Mt. Simon. The model assumption made 

about lateral homogeneity in permeability and porosity is important for determining brine flow and far147
field pressure, but it is not clear without better knowledge about lateral variability whether inclusion of 

heterogeneity would increase or decrease far-field effects. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jean-Philippe Nicot 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG) 

EPA Letter ID: 0381 

EPA Comment ID: 28099 

Comment: Comment related to the need of considering basin-scale evaluation early 

on. Impact of numerous large CCS projects has to be considered at the basin 

scale. Often lack of data makes modeling of such large scale injection 

problematic. Regulators need to be proactive and develop a mechanism for all 

operators, especially early entrants (at which time there is no such issue) to 

provide the information needed later for assessment and modeling of basin-scale 

impacts. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to §146.84 should account for the impacts of multiple owners and operators injecting within 

a single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. For additional information regarding EPA’s requirements for AoR 

delineation for GS projects, see the responses to comments on the proposed rule in the rulemaking 

docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

148
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jean-Philippe Nicot 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG) 

EPA Letter ID: 0381 

EPA Comment ID: 28100 

Comment: It is obvious that early projects will not have basin-scale consequences. 

However the addition of successive projects and the increase in cumulative mass 

injected will, on the long run, have a regional impact. Although CO2 plumes 

might not, elevated pressure footprints will overlap, suggesting that a somehow 

coordinated approach is needed from the start (even if it is understood that it 

is not an issue initially). Pressure zone of influence overlap, at what could be 

considered a semi-regional level, could pressurize potential leakage pathways 

(faults, boreholes) in a way that would not have been a concern for a single 

project. Some mechanisms must be put in place that will formally inform second 

and following entrants of projects initiated earlier. Impact of CO2 injection at 

a more regional level consists in displacing saline and brackish water up dip 

into fresh water aquifers. This cannot be a direct concern of individual 

operators but must be the responsibility of the regulatory entity. One of the 

limitations of the references cited in the NODA is the lack of data, in 

particular of information on shale/clayey layers acting as a cushion to absorb 

and slowly diffuse back the increase in pressure. It follows that the 

responsible regulatory agency must collect this type of information from all 

operators in order to be able to address the regional capacity. And this, 

largely before pressure overlap becomes an issue. As an example of practical 

approach, in an ideal world, each operator would provide information about 

formations overlying its injection site(s) either through direct feedback on the 

parameters of interest as measured in the field or by providing core samples. 

Individual Response: EPA agrees with the commenter about the significance of collecting necessary 

site characterization data and consideration of the cumulative effects of multiple injection sites in a 

given formation. Therefore, the final GS rule requires a detailed site-specific evaluation of local 

geologic conditions (§146.82) and modeling to delineate the AoR (§146.84) investigations for actual 

reservoirs. 

EPA clarifies that the final GS rule does not include requirements for basin-scale evaluations. However, 

EPA agrees that proactive management of basin scale concerns to maintain pressures within 

acceptable ranges is important, and encourages owners or operators and permitting authorities to 

communicate planned GS activities to maximize coordination and minimize pressure interference. If a 

149
permit applicant (or the permitting authority) is aware of pending GS projects near a proposed well, 

the AoR delineation performed pursuant to §146.84 should account for the impacts of multiple owners 

and operators injecting within a single basin. EPA anticipates that, where multiple operators are 

involved, the Director would not approve modeling that does not account for changes that may result 

from all injection operations. The proximity of injection sites to each other and the relative timing of 

each injection operation might indicate a possible increase in risk for the containment of the total CO2 

and/or the effects of hydraulic perturbations and brine displacement. For additional information 

regarding EPA’s requirements for AoR delineation for GS projects, see the responses to comments on 

the proposed rule in the rulemaking docket.

EPA recognizes that these overlap issues will become more prevalent as deployment of GS increases, 

and will collect and review data on early GS projects and how they may interact. As part of its 

adaptive rulemaking approach, EPA plans, every six years, to collect and review data on GS projects 

to determine whether the appropriate amount and types of information and appropriate 

documentation are being collected, and to determine if modifications to the requirements are 

appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27966 

Comment: Comment No. 19 

Page 44808 

Issue Topic from EPA's NODA 

LBNL studied a hypothetical, future scenario of GS in a sedimentary basin as an 

illustrative example to demonstrate the potential for basin-scale hydrologic 

impacts of CO2 storage (Birkholzer et al., 2008b). 

Carbon Sequestration Council Comments 

Modeling Issues: - The model assumes lateral homogeneity of all stratigraphic 

150
units. - Permeability in the Eau Claire Shale top seal may vary considerably in 

a lateral sense at regional scales (Arnold et al., 1996). In the model, the 

permeability is uniform. - Compressibility values of the Mount Simon are less 

than published values. Increasing compressibility would reduce the predicted 

pressure buildup. - It was noted in Juanes, 2006, that in general coarse grids 

overestimate CO2 movement and capillary trapping. The adaptive gridding 

approach used in the Illinois Basin model uses progressively larger grid cells 

away from the injection area. The largest cells near the edge of the basin are 

10 x 10 km, and the maximum thickness of any grid block was set to 10 m. The 

high aspect ratio and large size of these cells may introduce significant 

numerical dispersion in the model results. Conclusions based on the modeled 

brine flow out of the basin and far field pressure effects should be considered 

qualitative at best, given the constraints of the model. 

[Reference]: 

Arnold, T., Bahr, J., and Fantucci, R., 1996, Paleohydrogeology of the Upper 

Mississippi Valley Zinc-Lead District, in Sangster, D. F., ed., Carbonate-Hosted 

Lead-Zinc Deposits, Society of Economic Geologists Special Publication Number 4, 

p. 378-389. 

Juanes, R., Spiteri, E.J., Orr, F.M., and Blunt, M.J., 2006, Impact of relative 

permeability hysteresis on geological CO2 storage, Water Resource Research, Vol. 

42, No. 12, W12418. 

Individual Response: Regarding the comment on “lateral homogeneity” in the Eau Claire Shale top 

seal, EPA clarifies that the seal data were too sparse to reliably estimate lateral heterogeneity. The 

impact of seal permeability was evaluated in sensitivity cases assuming two different (homogeneous) 

seal permeability values (Birkholzer and Zhou, 2009). The general outcome of the simulation study 

(i.e., size of the pressure-affected region) was not strongly influenced by the parameter choice.

EPA also clarifies that the model choice for pore compressibility is discussed in detail in Zhou et al. 

(2009), and is believed to be well constrained. The pore compressibility used in the model was 

obtained through a pumping test in central Illinois, at a depth of 2000 m just north of the assumed 

injection area. Additional pumping tests available in shallower parts of the storage reservoir 

corroborate the chosen value. These values used in the model are within the range of pore 

compressibility reported for well-consolidated sandstones at in situ effective stresses representative of 

Mt. Simon. 

Regarding “gridding and numerical dispersion,” numerical dispersion is a concern for solute transport 

with sharp interfaces (advection-dispersion equation) and/or for multi-phase transport. For single 

151
phase flow, such as ground water flow and pressure perturbation, there is no numerical dispersion, 

only the possibility of small approximation errors. Thus there may be some gridding effect and 

numerical dispersion when simulating CO2 movement and capillary trapping, but this effect is small 

because the discretization is refined in the vicinity of each CO2 plume. As to the far-field pressure 

response, numerical dispersion is not an issue. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27968 

Comment: Comment No. 24 

Page 44808 

Issue Topic from EPA's NODA 

EPA believes that the example studied by LBN L illustrates the importance of 

basin-scale evaluation of reservoir pressures and far-field pressures resulting 

from CO2 injection. EPA requests comment on this study and welcomes additional 

studies that provide information on the need for basin-scale evaluations for GS 

injection. 

Carbon Sequestration Council Comments 

The model results are not applicable to Area of Review decisions for individual 

site selection this early in the development of geologic storage. Adaptive 

rule- making would allow for adjustments to encompass multi-project scenarios in 

the same basin if needed in the future. See MSG Joint Letter dated May 14, 

2009, Item 2 on suggested language for managing pressure interference. 

(Adoption of this recommended provision will help to address and manage multiproject interference concerns if and when they occur.) 

152
Individual Response: The results of the modeling study did not cause EPA to change any aspects of 

the site characterization or AoR delineation requirements for GS projects. The final GS rule focuses on 

permitting of individual GS wells and therefore does not include requirements for basin-scale 

evaluations. However, EPA agrees that proactive management of basin scale concerns to maintain 

pressures within acceptable ranges is important, and encourages owners or operators and permitting 

authorities to communicate planned GS activities to maximize coordination and minimize pressure 

interference. If a permit applicant (or the permitting authority) is aware of pending GS projects near a 

proposed well, the AoR delineation performed pursuant to §146.84 should account for the impacts of 

multiple owners and operators injecting within a single basin. EPA anticipates that, where multiple 

operators are involved, the Director would not approve modeling that does not account for changes 

that may result from all injection operations. The proximity of injection sites to each other and the 

relative timing of each injection operation might indicate a possible increase in risk for the 

containment of the total CO2 and/or the effects of hydraulic perturbations and brine displacement. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 29160 

Comment: Comment No. 20 

Page 44808 

Issue Topic from EPA's NODA 

[S]imulation runs indicated that injection pressures did not exceed fracture 

pressure or the maximum value used in the model for this basin. However, results 

also indicated that far- field pressure changes could propagate as far away as 

200 km (124 miles) from the core injection area where the geologic sequestration 

projects are located. 

Carbon Sequestration Council Comments 

153
The far-field pressure changes observed in the model are on the order of 1-2 

bars (14-29 psi). These changes are very small, and would not likely have been 

observed if the model had included lateral heterogeneities in permeability and 

porosity and higher compressibility. The predicted pressure perturbations are 

so minor that they could not be accurately distinguished from noise in routine 

pressure data collection. 

Individual Response: Regarding noise in pressure measurements, pressure changes of 1-2 bar 

should be easily distinguishable from noise in routine pressure data.

Regarding lateral variability, the model assumption made about lateral homogeneity in permeability 

and porosity is important for determining brine flow and far-field pressure, but it is not clear without 

better knowledge about lateral variability whether inclusion of heterogeneity would increase or 

decrease far-field effects.

The model choice for pore compressibility is discussed in detail in Zhou et al. (2009), and is believed 

to be well constrained. The pore compressibility used in the model was obtained through a pumping 

test in central Illinois, at a depth of 2000 m just north of the assumed injection area. Additional 

pumping tests available in shallower parts of the storage reservoir corroborate the chosen value. 

These values used in the model are within the range of pore compressibility reported for wellconsolidated sandstones at in situ effective stresses representative of Mt. Simon. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 29161 

Comment: Comment No. 21 

Page 44808 

Issue Topic from EPA's NODA 

"[A] pressure increase of 0.5 bar existed at an areal extent of nearly 400 km by 

154
400 km (249 miles by 249 miles) after 50 years. These model results indicate 

that basin-wide pressure influences can be large and may have intersecting 

pressure perturbations in a multiple-site scenario." 

Carbon Sequestration Council Comments 

Regarding the NODA summary of LBNL studies on "Basin-Scale Hydrologic Impacts of 

CO2Storage", we feel that a clarification of the results of this preliminary 

simulation and their implications are needed. In particular, it was noted that, 

a pressure increase of 0.5 bar might be expected at the distal extent of the 

regional aquifer (200 km from the core injection area). The next sentence 

states that "...basin-wide pressure influences can be large." This implies that 

0.5 bar (~0.5 atm) pressure elevation at the perimeter of the basin is "large". 

Whereas we recognize that pressure perturbations will be significant in the core 

injection area (especially where pressure fields intersect), a 0.5 bar increase 

in pressure at the basin perimeter is not significant in terms of threatening 

containment. 

Individual Response: EPA clarifies that the 0.5-bar pressure threshold was used as an example 

illustrating the enormous size of the region affected by some pressure perturbation; it was not meant 

to imply that a 0.5-bar pressure increase is a significant threat. However, even a more significant 5-

bar threshold would still result in a large pressure-affected region. The concern about pressure 

perturbation is that deep saline water could be pushed upward into overlying freshwater aquifers via 

potentially existing localized pathways. More research is needed to define at which point such 

pressure-induced localized flow might become a concern for USDW. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 29162 

Comment: Comment No. 22 

Page 44808 

155
Issue Topic from EPA's NODA 

While simulated changes in salinity within the storage formation were relatively 

small, the predicted pressure changes could push saline water upward into 

overlying aquifers if localized pathways such as conductive faults existed. 

Carbon Sequestration Council Comments 

Water displacement up dip was insignificant in this study as well as in Nicot, 

2008, in which the equivalent of 50 million tons of CO2 was injected annually 

for 50 years, resulting in an average water table rise of only about 1 meter. 

Storage locations with significant faulting would have to be carefully evaluated 

for leakage potential. The oil and gas industry has developed a variety of 

tools and workflows to predict whether a given fault is likely to leak. These 

processes have been tested on numerous hydrocarbon prospects and ground-truthed 

on faults known to seal or leak. 

Individual Response: EPA recognizes that water displacement updip (within the storage reservoir) is 

shown to be insignificant in LBNL's study as well as in Nicot et al. (2008). However, the concern about 

pressure perturbation is that deep saline water could be displaced upward into overlying USDWs via 

existing localized pathways, such as undetected faults. EPA also agrees that storage locations with 

significant faulting or with the potential for improperly sealed wells would have to be carefully 

evaluated for leakage potential.

It is for these reasons that the final GS rule requires extensive evaluation of the site, including AoR 

modeling that predicts the lateral and vertical migration of the CO2 plume and formation fluids 

(§146.84(c)(1)) and an evaluation of known or suspected faults and fractures in the AoR 

(§146.82(a)(3)) and all artificial penetrations in the AoR (§146.84(c)(2)). The final rule also requires 

corrective action to be performed on all wells to prevent the fluid movement into or between USDWs 

at §146.84(d). For additional information regarding EPA's requirements for AoR delineation for GS 

projects, see the responses to comments on the proposed rule in the rulemaking docket.

EPA also recognizes that the oil and gas industry has developed a variety of tools to predict whether a 

given fault is likely to leak. However, it should be noted that site characterization for faulting and 

abandoned wells will have to be done on a large scale, i.e., the size of the pressure-affected areas. 

EPA Team Member: 

Draft Status: 

156
Date Uploaded: 21-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 29163 

Comment: Comment No. 23 

Page 44808 

Issue Topic from EPA's NODA 

As these large scale simulations indicated, limitations on injection volumes 

related to basin-scale pressure build-up should be considered during CO2 

capacity estimation. 

Carbon Sequestration Council Comments 

Basin-scale modeling can be informative with respect to issues that may be faced 

in the future with multiple injection projects using the same storage reservoir 

in a given basin. The work of Birkholzer, Zhou and others (referred to as the 

authors herein) is illustrative in this regard in that it utilizes an actual but 

not yet fully characterized basin framework. In assessing the pressure field 

and brine migration potential developed as part of this work, it has to be 

clearly noted, however, that a spatially concentrated and certainly arbitrary 

injection scenario was required to generate the perturbations resulting in the 

model outcomes. The scenario was designed to create these perturbations and in 

itself is a far-end member of the range of scenarios that might be utilized. 

Certain assumptions also had to be made regarding increases in seal permeability 

to generate the model results and these assumptions need significant refinement. 

As such, this is acceptable as a modeling exercise and as a guide to future 

studies but not as a predictable outcome or even a generalized outcome, and in 

fact the authors call for further strategies for pressure monitoring and the 

improvement of predictive models. Although the authors highlight far-field 

impacts, it is premature for EPA to consider any basin-scale mandates other than 

intensive data collection and assessment, including support for improvement in 

basin-scale simulation models that are indicators of large-scale hydrologic 

157
impacts. This work must be taken as an indicator of a research need, given the 

hypothetical concentration of twenty large storage projects in a limited area, 

not of the need for developing any specific basin-scale regulations as part of 

the current Class VI development process. The latter approach would be 

counterproductive in that it may negate: (1) the development of multiple initial 

projects essential to more definitively define the very safeguards that 

groundwater protection strategies are designed to achieve, and (2) suppress the 

realization of more appropriate injection scenarios (rate, period, and 

placement) that would yield more realistic results than the inputs selected for 

the author's modeling. 

Support of this position is found in the authors work. They cite a Darcy flow 

velocity across the top model boundary, averaged over the model domain, of 0.47 

mm/year at 50 years of injection and an average Darcy velocity across the 

lateral boundaries of about half that value. The authors then go on to state: 

"The lateral migration distances of saline water associated with these boundary 

flows do not constitute a concern for the groundwater resources in overlying 

aquifers or neighboring basins." The authors also note that current groundwater 

withdrawal practices in the northern Illinois Basin are pulling saline water 

toward some water wells, and that "these impacts dwarf the predicted 

environmental consequences of the hypothetical CO2 storage scenario studied...". 

New data are being developed as a result of currently funded sequestration 

deployment testing. An example of the impacts of incompletely known chosen 

parameters can be seen in the discussion of hydraulic diffusivity. Recent work 

in the Illinois Basin indicates that the porosity value chosen for the modeling 

is low relative to higher porosity values obtained from recent drilling in the 

model injection area, thus recent data would tend to reduce the pressureaffected region outside of the injection area. The authors narrate a 

sensitivity case that, they state, would reduce the region from 190 km to only 

60 km in radius, but would also be dependent on lower permeability and greater 

compressibility, as well as the higher porosity. Again, initial storage project 

development must occur to better define key parameters. 

Further, it is also important to recognize that the discussion of the capacity 

assessments for the basin compared to the 50-year, 5,000 Mt perturbation in the 

model confuses the sequestration resource with basin capacity and the numbers in 

the DOE atlas are resources, not capacity. There is no expectation that the 

early DOE resource assessments would represent actual capacity. The authors 

statement that these resource estimates are subject to "an implicit assumption 

that the storage capacity is not constrained by pressure buildup and brine 

158
migration..." is incorrect, and researchers involved with creating these 

estimates would be unlikely to agree with this assumption. These are not undue 

criticisms of the work, simply an indication that definitions need to be refined 

and common terminology needs to become more widespread. The authors conclude 

that in a basin with multiple storage sites, industrial-scale storage projects 

are needed to supply valuable data "to reliably estimate the expected pressure 

impacts of later projects". That is certainly where we must go to answer key 

questions while acknowledging that the state of understanding of modeling basinscale sequestration impacts is in its early stages and is premature for rule 

making at this time. 

Individual Response: EPA agrees with the commenter regarding the need for comprehensive site 

characterization and data review of large-scale saline formations. The final GS rule requires owners or 

operators of GS wells to delineate the AoR for GS sites using computational fluid flow models designed 

for the specific site conditions and injection regime (e.g., current injection activities). Periodic 

revisions and recalibrations of the models must be conducted as described in the approved AoR and 

corrective action plan required at 146.84. The final rule also requires monitoring of the plume and the 

pressure front throughout the injection phase (146.90). For additional information regarding EPA’s 

requirements for AoR delineation for GS projects, see the responses to comments on the proposed 

rule in the rulemaking docket.

EPA acknowledges the need for improvement/validation of predictive models before considering basinscale mandates, and will continue to collect and review data on early GS projects as part of its 

adaptive rulemaking approach. EPA recognizes that inter-state and even international cooperation 

may be necessary where multiple injection operations may interact, but has no plans or authority to 

develop a basin-wide regulatory process. The final GS rule focuses on permitting of individual GS wells 

and therefore does not include requirements for basin-scale evaluations. EPA notes, however that the

GS rule, at §146.82(b), requires that the Director notify representatives of all states, tribes, and 

territories in the AoR to inform them of the permit application and offer them an opportunity to be 

involved in any relevant activities, such as development of the required project-specific plans.

Regarding the comment that the paper presents a spatially concentrated and arbitrary injection 

scenario, EPA notes that, considering the large volumes that need to be sequestered to make a 

contribution to climate change mitigation and the volumes that are produced from large stationary 

sources, it may be unrealistic to assume that storage sites can be placed so far from each other that 

their pressure envelopes would never overlap. The spatial pattern of GS projects used in LBNL’s work 

was developed by placing the 20 storage sites into the center area of the example basin where the 

geological conditions were most favorable for CO2 storage.

Regarding the assumption about seal permeability, the base simulation case in the basin-scale model 

159
used vertical permeability of seal of 1.0 × 10-18 m2. A sensitivity case was studied in Birkholzer et al. 

(2009) assuming a seal permeability of 1.0 × 10-20 m2. A higher seal permeability allows for 

pressure attenuation in the storage formation caused by slow diffuse brine migration into the seals. 

The two simulation cases reflect the range of seal properties available for the example basin, from 

core scale measurements and regional scale estimates (Zhou et al., 2009).

Regarding capacity, while EPA acknowledges differences in terminology (e.g., the resource estimates 

provided in USDOE (2008) correspond to effective capacities in the definition given in CSLF (2008) 

and the USDOE capacity estimates correspond to the CSLF practical capacities) the point Birkholzer 

and Zhou (2009) are trying to make is that the practice of estimating resource (or effective capacity) 

via efficiency factors does not include pressure and brine migration constraints. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28146 

Comment: C. Basin scale evaluations should be a governmental responsibility, not an 

individual company responsibility 

"EPA believes that the example studied by LBNL illustrates the importance of 

basin-scale evaluation of reservoir pressures and far-field pressures resulting 

from CO2 injection. EPA requests comment on this study and welcomes additional 

studies that provide information on the need for basin-scale evaluations for GS 

injection." (74 FR 44808) 

Spectra agrees that basin scale evaluations may be needed to ensure that there 

is adequate capacity in a given basin for all the geologic sequestration schemes 

in that basin. However, when the scope of an evaluation expands beyond the Area 

of Review (AoR) to be basin-scale, it requires a significantly higher level of 

resources; to place this as the responsibility of any one company would be 

overly burdensome. To ensure consistency and protect drinking water and 

subsurface assets, Spectra believes basin-scale evaluations should be a 

governmental responsibility; Spectra supports the development of these 

evaluations by the State(s), regional partnerships, and/or trans-border 

160
partnerships. 

Just as States maintain oversight of drinking water reservoirs and regulate oil 

and gas wells and storage facilities, States should retain the responsibility 

for maintaining overall assessments of the subsurface on a basin- wide scale, 

including sequestration sites. Individual States have a critical role in 

protecting and regulating the competing economic interests involved in utilizing 

the subsurface, not only for sequestration but also for natural gas storage, oil 

and gas production, mineral extraction, and other subsurface activities. Many 

State oil and gas regulations specify well siting or construction requirements 

for any wells that are drilled within a gas storage area or penetrate the 

storage horizon; this should be the same for geologic sequestration sites. 

Within the U.S., natural gas storage is generally located in two major geologic 

formations: porous rock reservoirs and salt caverns. Generally, the types of 

storage fields that will potentially be impacted by the Proposed Rule are porous 

rock reservoirs. Because many of the areas and geologic formations considered 

for GS will be in the same basins and may occur within or in close proximity to 

the same geologic strata, the State will need to monitor and evaluate natural 

gas storage sites and GS operations together, along with other competing 

subsurface interests. The appropriate level of CO2 storage for an entire basin 

is not a question that can be adequately answered by a single company wishing to 

operate in a given basin. Spectra suggests that appropriate regulatory agencies 

in individual States be active participants with the EPA in the GS permitting 

process, to ensure appropriate State knowledge of local geology is considered in 

a technical evaluation of the suitability of potential GS zones, and to develop 

and maintain basin-level studies of the subsurface in relation to CO2 GS. 

Further, there are already organizations established to develop these basinlevel studies at a regional level. For example, the Department of Energy RCSPs, 

such as PCOR, are developing a CCS "atlas" which is essentially a CO2 storage 

estimate. These Partnerships would be in a position to help each State with 

basin-level studies, using the RCSP atlas as a starting point. 

Additionally, under the Clean Energy Dialogue between the U.S. and Canada, the 

priorities include mapping of geological storage opportunities for CCS: 

Under the Clean Energy Dialogue, we recommend, as a top priority, the formation 

of a U.S.- Canada CCS Collaboration. The Collaboration will engage Canadian and 

U.S. experts on CCS from the public and private sectors to share best practices 

and conduct joint activities. This effort will: 

161
- Expand existing collaboration in CO2 injection and storage testing, 

share information from large-scale CCS demonstration projects, and work 

together to map CO2 sources and geological storage opportunities; (Clean 

Energy Dialogue First Report to Leaders, Sept 16, 2009) 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to 146.84 should account for the impacts of multiple owners and operators injecting within a 

single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the 

permitting of the newer GS project would have considered the presence of an existing GS project. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket.

EPA recognizes that inter-state and even international cooperation may be necessary where multiple 

injection operations may interact, but has no plans or authority to develop a basin-wide regulatory 

process. EPA adds that the GS rule, at §146.82(b), requires that the Director notify representatives of 

all states, tribes, and territories in the AoR to inform them of the permit application and offer them an 

opportunity to be involved in any relevant activities, such as development of the required projectspecific plans. The Agency will work with the appropriate entities to facilitate communication among 

States and Tribes interested in obtaining Primacy during the implementation phase of the GS 

regulation. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

162
Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28299 

Comment: B. LBNL Study of Basin-Scale Hydrologic Impacts of CO2 Sequestration 

Demonstrates the Need that EPA Administer this Regulatory Program because of 

Interstate Basin Issues. 

In addition, the LBNL studied a hypothetical, future scenario of geological 

sequestration in a sedimentary basin as an illustrative example to demonstrate 

the potential for basin-scale hydrologic impacts of CO2 storage. 74 Fed. Reg. 

44,808. The LBNL study indicated that "far-field pressure changes could 

propagate as far away as 200 km (124 miles) from the core injection area where 

the geologic sequestration projects are located." Id. "After CO2 injection ended 

in the simulation, pressure buildup in the injection zone began to dissipate 

while the far-field pressure response continued to increase and expand. For this 

simulation example, a pressure increase of 0.5 bar existed at an areal extent of 

nearly 400 km by 400 km (249 miles by 249 miles) after 50 years. These model 

results indicate that basin-wide pressure influences can be large and may have 

intersecting pressure perturbations in a multiple-site scenario." Id. 

The results of the LBNL study of basin-scale hydrologic impacts of CO2 

sequestration highlighted in the NODA demonstrate the potential for interference 

of far-field pressures in large-scale geological sequestration deployment. The 

results of this study underscore the need to have one central agency, the EPA, 

administer this program. Basin boundaries do not line up with state boundaries. 

Under the proposed regulations, if a basin covers multiple states, numerous 

state agencies would have authority to permit injections into the same basin. 

However, the proposed regulations do not require any interstate collaboration to 

account for interstate basin issues, such as basin wide pressure changes. The 

best way to ensure that interstate boundary issues, such as far-field pressure 

changes in a basin, are taken into account is to have one central agency issue 

all CCS permits. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive

management of basin scale concerns to maintain pressures within acceptable ranges is important, and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. If a permit applicant (or the permitting 

163
authority) is aware of pending GS projects near a proposed well, the AoR delineation performed 

pursuant to 146.84 should account for the impacts of multiple owners and operators injecting within a 

single basin. EPA anticipates that, where multiple operators are involved, the Director would not 

approve modeling that does not account for changes that may result from all injection operations. The 

proximity of injection sites to each other and the relative timing of each injection operation might 

indicate a possible increase in risk for the containment of the total CO2 and/or the effects of hydraulic 

perturbations and brine displacement. 

EPA adds that if any new GS projects are permitted within the AoR of a GS project between AoR 

evaluations, the AoR reevaluation would need to address such projects. EPA also expects that the 

permitting of the newer GS project would have considered the presence of an existing GS project. For 

additional information regarding EPA’s requirements for AoR delineation for GS projects, see the 

responses to comments on the proposed rule in the rulemaking docket.

EPA recognizes that inter-state and even international cooperation may be necessary where multiple 

injection operations may interact, but has no plans or authority to develop a basin-wide regulatory 

process. EPA notes, however that the GS rule, at §146.82(b), requires that the Director notify 

representatives of all states, tribes, and territories in the AoR to inform them of the permit application 

and offer them an opportunity to be involved in any relevant activities, such as development of the 

required project-specific plans. The Agency will work with the appropriate entities to facilitate 

communication among States and Tribes interested in obtaining Primacy during the implementation 

phase of the GS regulation. EPA clarifies that issuance and oversight of a GS permit is the 

responsibility of the primacy (State or Tribal) or regional DI program in the state where the injection 

well is located. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2300 2.3. Additional Research 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

164
Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Claire M. Olson 

Commenter Organization: Basin Electric Power Cooperative (Basin Electric) 

EPA Letter ID: 0351 

EPA Comment ID: 28053 

Comment: The IPCC's 2005 report on "Carbon Capture and Storage" notes that mature 

sedimentary basins such as the Williston Basin in the upper Great Plains are 

"prime targets for CO2storage because: (1) they have well-known characteristics; 

(2) hydrocarbon pools and/or coal beds have been discovered and produced; (3) 

some petroleum reservoirs might be already depleted, nearing depletion or 

abandoned as uneconomic without advanced production systems such as EOR: (4) the 

infrastructure needed for CO2 transport and injection may already be in place."1 

Use of CO2 for EOR often adds an additional 7-23% of incremental oil recovery 

from a field, and depleted oil fields have advantages for CO2 sequestration 

because "the oil and gas that originally accumulated in traps (structural and 

stratigraphic) did not escape (in some cases for many millions of years), 

demonstrating their integrity and safety," and because "the geological structure 

and physical properties of most oil and gas fields have been extensively studied 

and characterized..." [Footnote 2] IPCC's 2005 "Carbon Capture and Storage" 

Report also recognizes that Basin Electric's DGC Weyburn project, "despite the 

presence of many hundreds of existing wells, after four years of CO2 injection 

there has been no measurable leakage (Strutt et al., 2003)."[Footnote 3] Thus, EOR is an 

established option for CO2sequestration in the Williston Basin, and geological 

formations are holding sequestered CO2 without leakage. There is an identified 

need for additional CO2for EOR in the Williston Basin when the technology 

becomes mature enough to provide it at a reasonable cost to customers. Basin 

Electric's AVS Post-Combustion CO2 Capture Project is an attempt to move that 

technology forward. 

[Footnote 1]: IPCC "Carbon Capture and Storage" Report 

(2005), Chapter 5, p. 215, available at http://www.ipcc.ch/ipccreports/srcc.htm. 

[Footnote 2]: Id. 

[Footnote 3]: Id. 

In addition to EOR options, saline aquifers have been identified in the 

Mississippian Madison geological formation of the Williston Basin with the 

capacity to store approximately 60 gigatons (ie., 60 billion tons) of CO2, which 

is enough capacity, for example, to store all of the CO2 emitted from a facility 

emitting 3 million tons of CO2 per year for 20,000 years. 

165
IPCC's 2005 report on "Carbon Capture and Storage" also says that most scenarios 

project that the supply of primary energy used by humans will continue to be 

dominated by fossil fuels until the middle of the 21st-century.[Footnote 4] The 

IPCC notes that stabilizing CO2 levels in the atmosphere will not likely be 

achieved with a single technological option, but CO2 capture and storage (CCS) 

in geological formations is one of the most important technologies that may make 

such stabilization possible."[Footnote 5] 

[Footnote 4]: Id. at p. 3. 

[Footnote 5]: Id. at p.53. 

"[T]he global capacity to store CO2 deep underground is large. Depleted oil and 

gas reservoirs are estimated to have a storage capacity of 675-900 [metric 

gigatons of] CO2. Deep saline formations are very likely to have a storage 

capacity of at least 1000 [metric gigatons of] CO2 and some studies suggest it 

may be an order of magnitude greater than this, but quantification of the upper 

range is difficult until additional studies are undertaken."[Footnote 6] 

[Footnote 6]: Id. at p.197. 

The IPCC "Carbon Capture and Storage" Report acknowledges that natural 

underground accumulation of CO2 is "a widespread geological phenomenon," and 

that '[w]hile there are differences between natural accumulations and engineered 

storage, injecting CO2 into deep geological formations at carefully selected 

sites can store it underground for long periods of time: it is considered likely 

that 99% or more of the injected CO2 will be retained for 1000 years."[Footnote 7] 

[Footnote 7]: Id. at p.197. 

Geological sequestration of CO2 is, in sum, one of the important tools available 

for stabilizing CO2 levels in the atmosphere, and Basin Electric/DGC's Weyburn 

project is currently the largest carbon sequestration project in the world 

demonstrating the feasibility of such capture and storage. Whatever steps are 

taken either legislatively or through rulemaking to regulate CO2 and other 

greenhouse gases (GHGs) must allow CCS technology and other carbon and GHG 

control technologies to be developed, and must allow a reasonable time frame to 

do so. 

Individual Response: EPA agrees with the commenter that CCS is an important technology for 

reduction of CO2 emissions to the atmosphere, and is committed to research and development of CCS 

166
in cooperation with other federal agencies and States. EPA also agrees with the commenter that 

sedimentary basins, such as the Williston Basin, and oil and gas reservoirs, such as the Weyburn field, 

are attractive targets for GS. 

EPA acknowledges the comment that a certain percentage of CO2 used in ER may be trapped in the 

receiving formation and be permanently stored. However, EPA believes that further data is needed to 

better characterize the movement and leakage of CO2 at ER sites, as well as the amount that remains 

sequestered after injection ceases. Importantly, ER projects are operated to minimize CO2 use and 

maximize oil or gas production. Operation of GS sites, while similar to ER in some respects, will exhibit 

the fundamentally different objective of maximizing CO2 injection and sequestration. Therefore, EPA 

anticipates that the risk posed by GS projects to USDWs will be greater than currently operated EOR 

projects, and warrant today’s tailored set of requirements. For this reason, EPA is requiring in today’s 

final regulation that all projects injecting CO2 into an active or depleted oil or gas reservoir for the 

primary purpose of long-term storage seek a Class VI permit. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2310 2.3.1. Review of Modeling Studies (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28043 

Comment: CO2 Modeling 

EPA states that "modeling the injection and sequestration of CO2 poses unique 

challenges" (NODA p. 44808). This statement exaggerates the challenges and 

167
fails to take into account the modeling experience of industry. Industry is 

constantly being faced with new situations that pose "unique challenges". For 

example, development of the Canadian oil sands presented "unique challenges" 

such as simulating heavy oil thermal recovery operations which require steam 

injection into shallow reservoirs at high temperature, causing thermal 

alteration of the oil, reactivity of mineral species, and over pressurization. 

These operations are more complicated and more chemically reactive than CO2 

storage operations yet industry now does this type of modeling routinely. This 

shows industry's ability to overcome challenges in order to effectively model 

highly complex and dynamic subsurface processes. 

Additionally, the state of modeling for CO2 storage is more than adequate to 

proceed with EPA rule promulgation. Additional research is always encouraged, 

but there are no major technical breakthroughs in the realm of modeling that 

need to occur before beginning commercial-scale CO2 storage operations in the 

United States. Adaptive regulations will facilitate new information being 

implemented in a responsible way. 

API does not support EPA's assertion that there is a ". . . need to couple 

multiphase flow, reactive transport, and geomechanical processes" (NODA 

p.44808). Such a model is certainly possible but will likely be intractable, 

expensive, and it will still be at the mercy of the quality of the input and the 

fundamental model framework. It is more important to correctly capture the 

range of processes and possible outcomes at a given location than to use a 

particular software package or type of modeling. Robust yet less complex models 

capturing the most important physical and chemical processes can accomplish the 

modeling goals necessary for safe storage. 

Lastly, the Schnaar and Digiulio, 2009 literature review on CO2 modeling, which 

appears to be the basis for EPA's statements above, focuses heavily on finite 

difference simulation of CO2 storage in saline aquifers.[Footnote 10] It has few 

references to analogous modeling of CO2-EOR storage and underground gas storage. 

It also lacks discussion of alternative flow modeling theories (e.g. 

percolation) that could be applied to certain geologic storage applications. 

[Footnote 10] Schnarr, G. and D. Digiulio. 2009. Computational Modeling of 

the Geologic Sequestration of Carbon Dioxide. Vadose Zone Journal, 8(2), 389-403. 

Individual Response: EPA believes that modeling of CO2 injection for GS does pose several unique 

challenges, based on review of relevant technical literature, and participation in several technical 

168
symposia and workshops related to computational modeling in this area. While this type of 

multiphase, non-isothermal, multi-component computational modeling may be familiar in certain 

advanced industries, it is certainly novel to the UIC community, and is more sophisticated than 

modeling typically required in U.S. EPA regulations. However, EPA agrees with the commenter that 

advanced computational modeling of GS sites is feasible, and trusts that experts in industry will meet 

the challenges posed by GS modeling. For this reason, EPA has required computational modeling for 

delineation of the AoR in a Class VI permit application. 

EPA also agrees with the commenter that coupling of multiphase flow, reactive transport, and 

geomechanical processes may not be necessary in all cases for modeling to delineate the AoR in a 

Class VI permit application. EPA clarifies that today’s federal regulation requires that models used for 

AoR delineation be able to account for multiphase flow and the buoyancy of CO2. However, the 

Director has the discretion to require more advanced models be used for AoR delineation, including 

additional coupling of reactive transport and geomechanical processes. EPA agrees with the 

commenter that these types of fully coupled models are possible, and believes that in certain cases 

they will be necessary for accurate delineation of the AoR. For many projects, however, simpler 

models, as advocated by the commenter, may be suitable for AoR delineation. EPA believes that the 

Director of individual projects is in the best position to determine the specific technical requirements of 

the model(s) used. 

EPA does not agree with the commenter regarding comments on the modeling research review paper 

cited in the NODA (Schnaar and Digiulio, 2009). This paper provides a comprehensive review of peerreviewed modeling studies of GS available in the technical literature, including studies of GS in oil and 

gas reservoirs, and studies using modeling codes common in petroleum engineering (e.g., ECLIPSE). 

Furthermore, the review paper provides a discussion and review of a range of simulators used to 

model GS, including simpler analytic and semi-analytic approaches cited by the commenter. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28098 

Comment: CO2 Modeling 

EPA states that "modeling the injection and sequestration of CO2 poses unique 

169
challenges" (NODA p. 44808). While on its face true, the statement exaggerates 

the challenges. Industry is constantly being faced with new situations that pose 

'unique challenges". For example in the Canadian oil sands, industry routinely 

simulates heavy oil thermal recovery operations which require steam injection 

into shallow reservoirs at high temperature, causing thermal alteration of the 

oil, reactivity of mineral species, and overpressure. These operations are more 

complicated and more chemically reactive than CO2 storage operations. Industry 

has extensive experience in these types of simulations, and though not a perfect 

analog for CO2 storage, it shows that we can model highly complex and dynamic 

subsurface processes. 

The fact is that the state of modeling for CO2 storage is more than adequate to 

proceed with EPA rule promulgation. Additional research is of course encouraged, 

but there are no major technical breakthroughs in the realm of modeling that 

need to occur before beginning commercial-scale CO2 storage operations in the 

United States. Adaptive regulations will facilitate new information being 

implemented in a responsible way. 

APC takes exception to EPA’s assertion that there is a ". . . need to couple 

multiphase flow, reactive transport, and geomechanical processes" (NODA 

p.44808). Such a model is certainly possible but will likely be intractable, 

expensive, and it will still be at the mercy of the quality of the input. It is 

more important to correctly capture the range of processes and possible outcomes 

at a given location than to use a particular software package or type of 

modeling. Robust yet less complex models capturing the most important physical 

and chemical processes can accomplish the modeling goals necessary for safe 

storage. 

Individual Response: EPA believes that modeling of CO2 injection for GS does pose several unique 

challenges, based on review of relevant technical literature, and participation in several technical 

symposia and workshops related to computational modeling in this area. While this type of 

multiphase, non-isothermal, multi-component computational modeling may be familiar in certain 

advanced industries, it is certainly novel to the UIC community, and is more sophisticated than 

modeling typically required in U.S. EPA regulations. However, EPA agrees with the commenter that 

advanced computational modeling of GS sites is feasible, and trusts that experts in industry will meet 

the challenges posed by GS modeling. For this reason, EPA has required computational modeling for 

delineation of the AoR in a Class VI permit application. 

EPA also agrees with the commenter that coupling of multiphase flow, reactive transport, and 

geomechanical processes may not be necessary in all cases for modeling to delineate the AoR in a 

170
Class VI permit application. EPA clarifies that today’s federal regulation requires that models used for 

AoR delineation be able to account for multiphase flow and the buoyancy of CO2. However, the 

Director has the discretion to require more advanced models be used for AoR delineation, including 

additional coupling of reactive transport and geomechanical processes. EPA agrees with the 

commenter that these types of fully coupled models are possible, and believes that in certain cases 

they will be necessary for accurate delineation of the AoR. For many projects, however, simpler 

models, as advocated by the commenter, may be suitable for AoR delineation. EPA believes that the 

Director of individual projects is in the best position to determine the specific technical requirements of 

the model(s) used. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 28656 

Comment: Comment No. 25 

Page 44808 

Issue Topic from EPA's NODA 

Schnaar and Digiulio (2009) present a research review of over forty GS modeling 

studies spanning from 1993-2008. The complete modeling review is available in 

the online public docket at www.regulations.gov. 

Carbon Sequestration Council Comments 

The identified "need to couple multiphase flow, reactive transport, and 

geomechanical processes" (NODA p.44808) is an idealized concept rather than a 

true need. Such a model is certainly possible but will likely be intractable, 

expensive, and it will still be at the mercy of the quality of the input. It is 

more important to correctly capture the range of processes and possible outcomes 

at a given location than to use a particular software package or type of 

modeling. Robust yet less complex models capturing the most important physical 

and chemical processes can accomplish the modeling goals necessary for safe 

171
storage. 

The Schnaar and Digiulio, 2009 literature review on CO2 modeling focuses heavily 

on finite difference simulation of CO2 storage in saline aquifers. It is short 

on references to analogous modeling of CO2-EOR storage and underground gas 

storage, and also short on alternative flow modeling theories which could be 

applied to certain geologic storage applications. 

Individual Response: EPA agrees with the commenter that coupling of multiphase flow, reactive 

transport, and geomechanical processes may not be necessary in all cases for modeling to delineate 

the AoR in a Class VI permit application. EPA clarifies that today’s federal regulation requires that 

models used for AoR delineation be able to account for multiphase flow and the buoyancy of CO2. 

However, the Director has the discretion to require more advanced models be used for AoR 

delineation, including additional coupling of reactive transport and geomechanical processes. EPA 

agrees with the commenter that these types of fully coupled models are possible, and believes that in 

certain cases they will be necessary for accurate delineation of the AoR. For many projects, however, 

simpler models, as advocated by the commenter, may be suitable for AoR delineation. EPA believes 

that the Director of individual projects is in the best position to determine the specific technical 

requirements of the model(s) used.

EPA does not agree with the commenter regarding comments on the modeling research review paper 

cited in the NODA (Schnaar and Digiulio, 2009). This paper provides a comprehensive review of peerreviewed modeling studies of GS available in the technical literature, including studies of GS in oil and 

gas reservoirs, and studies using modeling codes common in petroleum engineering (e.g., ECLIPSE). 

Furthermore, the review paper provides a discussion and review of a range of simulators used to 

model GS, including simpler analytic and semi-analytic approaches cited by the commenter. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2320 2.3.2. Recent Publications on Risk and Risk Management 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

172
Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27981 

Other EPA Comment Codes and Descriptions: 3130 3.1.3. Addressing the Differences Between 

Class II and Class VI Wells 

Comment: Comment No. 38 

Page 44810 

Issue Topic from EPA's NODA 

Third, because the Agency believes that it is necessary to address the specific, 

unique characteristics of Class VI injection (e.g., large injection volumes, 

viscosity, and buoyancy) and the Agency does not have information or data 

indicating that Class II operations are entirely analogous to Class VI, largescale injection, this alternative allows Class VI injection depth considerations 

to be tailored for GS. 

Carbon Sequestration Council Comments 

Within the past year, there have been several papers that have demonstrated this 

excellent record of producing, transporting, and injecting CO2. The first study 

by Duncan et al. (2009) examines the safety risks associated with large scale 

CO2 sequestration by taking a systematic review of all accident and blowout data 

associated with CO2 pipeline transport and injection and finds that "The CO2-EOR 

industry has an excellent safety record" and "the rarity of corrosion related 

incidents reflects the industries [sic] success in implementing anti-corrosion 

measures." The second study by Smyth et al. (2009) demonstrates the industry's 

protection of the environment. It examines the groundwater in the SACROC CO2- 

EOR field and finds "that no widespread degradation of water quality exists 

inside the SACROC oilfiled [sic] as a result of CO2-injection." A third study 

on the mechanical integrity of CO2 injection wells is in progress and should be 

completed in time for consideration by EPA. 

[References]: 

173
Duncan, I., Nicot, J. P., and Choi, J., 2009, Risk assessment for future CO2 

sequestration projects based on CO2 enhanced oil recovery in the U.S., GHGT-9, 

Energy Procedia I, 2037-2042 - presented at the 9th International Conference on 

Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., November 16-20, 

2008. GCCC Digital Publication Series #08-03i. 

Smyth, R.C., Hovarka, S., Lu, J., Romanak, K., Partin, J., Wong, C., and Yang, 

C., 2009, Assessing risk to fresh water resources form long term CO2 injection - 

laboratory and field studies, GHGT-9, Energy Procedia I: 1957-1964 - paper GCCC 

Digital Publication Series #08-03j, presented at the 9th International 

Conference on Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., 

November 16-20, 2008. Download from BEG/UT website: 

http://www.beg.utexas.edu/gccc/bookshelf/2008/GHGT9/08-03j-Final.pdf. 

Individual Response: EPA acknowledges that several recent and ongoing studies are examining the 

risks associated with CCS, including those studies cited by the commenter, which focus on drawing an 

analogy between ongoing ER projects and CCS. As part of its commitment to an adaptive rulemaking 

approach for wells, EPA is tracking the results of GS-related research and data collected from early GS 

projects. 

EPA agrees with the commenter that industry experience injecting CO2 for the purpose of ER must be 

leveraged in implementation of GS. However, operation of GS sites, while similar to ER in some 

respects, will exhibit the fundamentally different objective of maximizing CO2 injection and 

sequestration. ER projects are operated to minimize CO2 use and maximize oil or gas production. 

Therefore, EPA anticipates that the risk posed by GS projects to USDWs will be greater than currently 

operated ER projects and has designed the Class VI GS requirements accordingly. EPA adds that it has 

been monitoring progress at the SACROC site.

As part of its commitment to an adaptive rulemaking approach for wells, EPA will continue to review 

GS-related research such as the forthcoming MIT report and data collected from early GS projects 

such as SACROC. The Agency will evaluate the information and determine whether modifications to 

the requirements are necessary to protect USDWs from endangerment.

EPA has reviewed the cited studies as part of the final rulemaking. EPA notes that although Duncan et 

al. noted that "[t]he CO2-EOR industry has an excellent safety record," their paper is based on case 

studies and does not provide failure rates, so the safety of the industry as a whole cannot be 

quantified. EPA also notes that Smyth et al. indicate that the methods used to detect leaks of CO2 

from ER were not adequate to determine if leaks had occurred. 

EPA Team Member: 

Draft Status: 

174
Date Uploaded: 23-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 2400 2.4. Other Research Offered by Commenters (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeffrey A. Miller 

Commenter Organization: 

EPA Letter ID: 0331 

EPA Comment ID: 27931 

Comment: When the economy grows there is the ability to look towards programs believed to 

cleanup the environment. The intention is not to present a case for CO2 in the 

environmental and the benefits and harms imposed thereon but to present an 

objective analysis of the sequestration reservoir characteristics based on over 

100 years of petroleum engineering. The analysis presented in the attached 

paper is based on commonly used and accepted approaches for evaluating reservoir 

characteristics. 

The Society of Petroleum Engineers paper titled, "The Impact of Carbon Geologic 

Sequestration," by Xian Vie, University of Wyoming and Michael J. Economides, 

SPE, University of Houston presents a generic analysis on the hurdles, scope, 

cost, and impact to the supposed global temperature increase imposed on the 

earth by CO2 emissions. [SEE EPA-HQ-OW-2008-0390-0331.PDF FOR ARTICLE] 

Based on this analysis a large number of carbon sequestration wells on the order 

of 7,000 to 66,500 were needed in 2008 to achieve the Kyoto Protocol emissions 

reductions. This number escalates to 16,700 to 161,500 by 2030. The ability to 

drill, complete and service these wells would highly likely stretch the US 

productive drilling capabilities directing the resources from production to 

175
sequestration. Other critical technological hurdles yet to be addressed are 

discussed below. 

Another critical analysis I have not found until this paper was published was an 

objective reservoir analysis using petroleum engineering equations developed 

from over 100 years of collective experience. The analysis demonstrates that 

injectivity decays over time as the CO2 reaches reservoir boundaries, more 

commonly understood as compaction. As a result, additional wells are needed to 

continue sequestration of the steady state emissions from the power plant. 

Individual Response: EPA has reviewed the paper entitled “The Impact of Carbon Geologic 

Sequestration.” EPA acknowledges the submittal and will continue to review studies related to 

estimations of the number of GS wells that may be drilled and used, limitations to injectivity, and the 

subsequent need for additional drilling as it makes changes to adapt in light of new data and research. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Emily Rochon 

Commenter Organization: Greenpeace International 

EPA Letter ID: 0342 

EPA Comment ID: 28029 

Comment: In addition to the research mentioned, Greenpeace would recommend that the EPA 

review the following: 

- Gilfillan, S.M.V. et al. Nature 458, 614-618 (2009). This study adds to the 

body of knowledge regarding primary trapping mechanisms for CO2 and counters the 

previously held notion that the primary trapping mechanism of CO2 is geological 

mineral fixation. Instead, the research indicates that the primary mechanism is 

dissolution which raises concerns about the permanence of CO2 storage, etc. 

- Lee, J-Y. et al. Journal of the Air & Waste Management Association 59, 725-728 

(2009). This study quantifies the flue gas components, other than CO2, that are 

present in a separated CO2 stream. 

- Bjureby, E. et al. Reality Check on Carbon Storage, Greenpeace Publications 

176
(2009). Available at: www.greenpeace.org/utsira. By examining the world's 

longest running CO2 storage project - the Sleipner project, and the Utsira 

formation on which it is located - this briefing highlights some of the major 

challenges and uncertainties facing CCS; and raises questions about the degree 

of certainty with which we can assess leakage or guarantee permanent storage of 

CO2 in projects such as these. 

Individual Response: EPA acknowledges the submittals and will continue to review studies of this 

nature. EPA intends to continue to collect data on GS and to incorporate such data and information as 

it implements its adaptive approach to the GS rulemaking to incorporate new research, data, and 

information about GS. For more information on the adaptive approach, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28038 

Comment: Several recent papers demonstrate the effectiveness of the Class II UIC program. 

The first study by Duncan et al. examines the safety risks associated with large 

scale CO2 sequestration by taking a systematic review of all accident and 

blowout data associated with CO2 pipeline transport and injection and concludes 

that "The CO2-EOR industry has an excellent safety record" and "the rarity of 

corrosion related incidents reflects the industry's success in implementing 

anti-corrosion measures." [Footnote 2] The second study by Smyth et al. 

demonstrates the industry's protection of the environment. It examines the 

groundwater in the SACROC CO2-EOR field and finds "that no widespread 

degradation of water quality exists inside the SACROC oilfield as a result of 

CO2-injection." [Footnote 3] 

[Footnote 2]: Duncan, I.J., Nicot, J.P., Choi, J.W.: "Risk assessment for future 

CO2 Sequestration Projects Based CO2 Enhanced Oil Recovery in the U.S.," 

presented at the 9th International Conference on Greenhouse Gas Control 

Technologies (GHGT-9), Washington, D.C., November 16-20, 2008. GCCC Digital 

177
Publication Series #08-03i 

[Footnote 3]: Smyth, R.C., Hovorka, S.D., Lu, J., Romanak, K.D., Partin, J.W., 

Wong, C. and Yang, C.: "Assessing risk to fresh water resources from long term 

CO2 injection - laboratory and field studies," paper GCCC Digital Publication 

Series #08-03j, presented at the 9th International Conference on Greenhouse Gas 

Control Technologies (GHGT-9), Washington, D.C., November 16-20, 2008. Download 

from BEG/UT website: 

http://www.beg.utexas.edu/gccc/bookshelf/2008/GHGT9/08-03j-Final.pdf 

Individual Response: EPA acknowledges the submittal and will continue to review studies related to 

the use of CO2 for ER and risk to fresh water resources from CO2 injection. EPA intends to continue to 

collect data on GS and to incorporate such data and information as it implements its adaptive 

approach to the GS rulemaking to incorporate new research, data, and information about GS. For 

more information on the adaptive approach, see the responses to comments on the proposed rule in 

the rulemaking docket.

EPA recognizes that the oil and gas industry has decades of experience injecting CO2 and has 

demonstrated the effectiveness of many of the technologies that will be employed at GS sites. The GS 

rule builds on this expertise with requirements tailored to the unique issues associated with GS 

through proper permitting, siting, well construction, operation, monitoring, and closure of GS projects. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28657 

Comment: Third, actual field results - as opposed to modeling exercises - have shown the 

risk of contamination is low. For example, at SACROC oilfield in Scurry County, 

TX, where CO2 has been injected for EOR since 1972, Smyth et al., 2009 

determined that "[They] do not see evidence of As or Pb having been mobilized 

from injection zones at SACROC into overlying USDW's . . .". [Footnote 6] 

[Footnote 6]: Smyth, R.C., Hovarka, S., Lu, J., Romanak, K., Partin, J., Wong, 

178
C., and Yang, C., 2009, Assessing risk to fresh water resources form long term 

CO2 injection - laboratory and field studies, GHGT-9, Energy Procedia I: 

1957-1964. 

The LBNL report's authors realize the limitations to their models and EPA should 

also. Despite having set up the simulation so that trace element mobilization 

would likely result, the authors conclude that ". . . model uncertainties, 

kinetic factors, and post-withdrawal water treatment methods all suggest 

diligence rather than alarm." [Footnote 7] 

[Footnote 7]: Apps, J. A., Zhang, Y., Zheng, L., Xu, T., and Birkholzer, J., 

2009, Identification of thermodynamic controls defining the concentrations of 

hazardous elements in potable ground waters and the potential impact of 

increasing carbon dioxide partial pressure, GHGT-9, Energy Procedia I, 

1917-1924. 

Individual Response: EPA has reviewed the papers and acknowledges the submittal. EPA will 

continue to review studies related to the evaluation of actual field results and the limitations of 

sampling and analysis, as well as the limitations of modeling. EPA intends to continue to collect data 

on GS and to incorporate such data and information as it implements its adaptive approach to the GS 

rulemaking to incorporate new research, data, and information about GS. For more information on the 

adaptive approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 172 to 193, which is an excerpt from the previous 

section, lines 137 to 193. This comment appears twice in this report, once for each set of line 

numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28080 

Comment: Page 44808: "The Agency seeks comment on this research and any additional 

studies related to a) mobilization of constituents and b) the likelihood or 

frequency of such leakage/risks." 

179
EPRI COMMENT #3: As noted in the NODA, the Lawrence Berkeley National Laboratory 

(LBNL) project was a modeling study and, therefore, calls for experimental 

verification before reaching definitive conclusions. To this end, EPRI 

conducted an initial field study and analysis of the potential impact of CO2 on 

shallow groundwater, to be completed by the end of 2009. The field study was 

performed at the Zero Emission Research and Technology (ZERT) field site in 

Bozeman, Montana; ZERT was hosted by Montana State University and was designed 

to test instruments used to detect leaks of CO2 to the surface and not 

groundwater impacts. ZERT injected food-grade CO2 into shallow groundwater in 

2008 over a thirty day period. Under the EPRI study, more than 80 groundwater 

samples were collected and analyzed using very low detection levels by the US 

Geological Survey, under contract to LBNL and EPRI. We observed increases in the 

groundwater concentration of several major cations and trace elements above 

background, including arsenic and lead, after CO2 injection began, but none of 

the constituents exceeded their respective action levels or maximum contaminant 

levels. Only three of the constituents, iron, manganese and total dissolved 

solids, exceeded the standard under which they are regulated, in this case the 

secondary drinking water criteria. It is our understanding that the EPA 

secondary drinking water criteria are not federally enforceable but are intended 

as guidelines for the states. These regulations control constituents in drinking 

water that primarily affect the aesthetic qualities relating to the public 

acceptance of drinking water. 

However, the ZERT site conditions were not ideal for studying the effects of CO2 

on potable groundwater for several reasons: 

1. Shallow (<6 feet) unconfined groundwater aquifers like that at the ZERT field 

site are not typically representative of USDWs because they do not have an upper 

confining unit that serves to protect the aquifer from surface contamination; 

2. Shallow aquifers respond to atmospheric conditions including recharge from 

precipitation and oxidizing conditions that influence experiment results; 

3. Deeper aquifers, which are representative of USDWs, lie below confining units 

that serve as barriers to surface contamination; 

4. Reducing conditions are more prevalent in deeper aquifers potentially 

resulting in different experimental outcomes than observed at ZERT; 

5. Results from 2008 study may underestimate impacts since a similar injection 

conducted in 2007 injection may have biased the later results. 

180
Therefore, EPRI and its members, recognizing the need for more definitive data, 

are about to embark on a three-year field study specifically designed to 

evaluate the impact of CO2 on potable groundwater, identify key reactive 

transport mechanisms, calibrate and validate flow and reactive transport models, 

and test the ability of existing models to predict transport behavior. These 

results provide an opportunity for improving models for commercial use; such 

models would be a tool for assessing CO2 GS projects. 

Individual Response: EPA has reviewed the information on the Zero Emission Research and 

Technology (ZERT) field site. EPA acknowledges the submittal and will continue to review studies 

related to modeling verification, comparisons with field results of CO2 injection, and the study of the 

effects of CO2 on shallow ground water. EPA intends to continue to collect data on GS and to 

incorporate such data and information as it implements its adaptive approach to the GS rulemaking to 

incorporate new research, data, and information about GS. For more information on the adaptive 

approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28248 

Comment: In September 2009, the U.S. Department of Energy announced grant awards for two 

projects to conduct site characterization of promising offshore geologic 

formations for CO2 storage: Terralog Technologies USA, Inc, investigating 

formations offshore Los Angeles, CA; and University of Texas at Austin, 

investigating formations offshore Texas in the Gulf of Mexico. 

In addition, the State of New Jersey is currently in the process of joining the 

USDOE-sponsored Midwest Regional Carbon Sequestration Partnership to conduct an 

assessment of geological sequestration capacity in New Jersey and the adjacent 

offshore region. 

181
Individual Response: EPA acknowledges the submittal. EPA is aware of the GS projects described 

and will continue to review studies of this nature. EPA intends to continue to collect data on GS and to 

incorporate such data and information as it implements its adaptive approach to the GS rulemaking to 

incorporate new research, data, and information about GS. For more information on the adaptive 

approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28270 

Comment: generation plants. APS has worked with Westcarb and other Arizona utilities on a 

DOE funded project to drill an experimental CO2 sequestration test well at our 

Cholla Power Plant near Holbrook, Arizona. APS has also recently received 

funding from DOE to study the feasibility of reusing CO2 from the plant to grow 

algae that later can be processed into liquid transportation fuels. 

Individual Response: EPA acknowledges the submittal. EPA is aware of the Cholla GS project 

described and will continue to review studies of this nature. EPA intends to continue to collect data on 

GS and to incorporate such data and information as it implements its adaptive approach to the GS 

rulemaking to incorporate new research, data, and information about GS. For more information on the 

adaptive approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28273 

182
Comment: coal-fired power plants. Over the last two years APS has worked with Westcarb 

and other Arizona utilities on a DOE funded project to drill an experimental CO2 

sequestration test well on our Cholla Power Plant property near Holbrook, 

Arizona. APS also recently received funding from DOE to study the feasibility of 

a fully integrated energy system for beneficial CO2 use. The CO2 produced by the 

power plant is fed directly to an algae farm, which consumes CO2. The algae will 

then be processed into liquid transportation fuels (e.g. biodiesel, ethanol, and 

military fuel), constituting a beneficial reuse of CO2. 

Individual Response: EPA acknowledges the submittal. EPA is aware of the Cholla GS project 

described and will continue to review studies of this nature. EPA intends to continue to collect data on 

GS and to incorporate such data and information as it implements its adaptive approach to the GS 

rulemaking to incorporate new research, data, and information about GS. For more information on the 

adaptive approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Katherine Romanak 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG), Gulf 

Coast Carbon Center (GCCC) 

EPA Letter ID: 0370 

EPA Comment ID: 27947 

Comment: The attached document details results of the DOE/NETL-funded (through SWP) field 

study of drinking water resources at the SACROC oilfield in west Texas. This 

study, which has been conducted by researchers of the Bureau of Economic 

Geology, Jackson School of Geosciences at The University of Texas at Austin 

(BEG), satisfies the LBNL suggestion that field studies be conducted to assess 

impacts to drinking water resources from CO2 injection. Conclusions from this 

study are included in several comments being submitted by BEG researchers. 

In summary, BEG researchers have not detected injectate CO2 in the Dockum 

aquifer at the SACROC oilfield. However, our findings do suggest that monitoring 

of natural parameters (pH, alkalinity, cations, etc.) in shallow aquifers may 

not be effective for evaluation of CO2 storage permanence. Knowledge of 

background variability and an understanding of processes controlling groundwater 

183
geochemistry are necessary for making correct interpretations regarding the 

presence of sequestered CO2 in aquifers at GS sites. Regardless, there are no 

discernible impacts to drinking water resources as a result of CO2 injection at 

the SACROC oilfield. 

Executive Summary: Recent results of the SACROC Groundwater Geochemistry Study 

Romanak, K.D., Smyth, R.C., Yang, C., Hovorka, S.D., Nicot, J.P., Lu, J. Gulf 

Coast Carbon Center, Bureau of Economic Geology, The University of Texas at 

Austin 

 

Executive Summary 

The purpose of this document is to report a summary of recent results and 

research of the SACROC groundwater quality study and their relation to geologic 

sequestration (GS) of CO2. The research was conducted by scientists at the Gulf 

Coast Carbon Center (GCCC) as part of the NETL Southwest Carbon Partnership 

Phase II (SWP) research. The results of this study were not available before the 

publication of the July 25, 2008, proposed rule, "Federal Requirements Under 

the Underground Injection Control (UIC) Program for Carbon Dioxide (CO2) 

Geologic Sequestration (GS) Wells'' (73 FR 43492). The work is currently being 

written for peer review publication in Applied Geochemistry to be submitted by 

the end of 2009, and is useful for consideration of amendments to the Safe Water 

Drinking Act. Additional details can be found in Smyth et. al., 2009; Romanak 

et. al., 2008 and 2009; and in the document, Modeling shallow groundwater 

geochemistry and carbon isotopes: test of methodology for CO2storage evaluation 

at an EOR site, west Texas, USA, published at http://www.beg.utexas.edu/gccc/. 

Our examination of groundwater geochemistry at a site where CO2 has been 

injected for decades shows that monitoring of natural parameters (pH, 

alkalinity, etc.) in shallow aquifers may be impractical and/or ineffective for 

evaluation of CO2 storage permanence. At the very least, detailed analysis of 

background variability and processes controlling groundwater geochemistry would 

be required on a case by case basis to confirm correct interpretations. Our 

analysis shows that to detect possible CO2 leakage into an underground source of 

drinking water (USDW) it is important to characterize the hydrogeologic context. 

Sampling at a few wells without understanding the hydrogeologic context could 

lead to erroneous interpretations. Errors could be either at sites where CO2 

leakage has occurred but is not detectable or at sites where non?injection 

induced changes are mistakenly assumed to indicate leakage. We have found that 

184
background variability in aquifers may mask the effects of even moderate 

anthropogenic CO2 input at GS sites rendering it impossible to discriminate 

changes in natural biogenic CO2 from anthropogenic inputs. 

Introduction 

Monitoring groundwater resources above geologic carbon sequestration reservoirs 

is proposed for ensuring that potable water supplies remain protected and also 

for establishing that CO2 is adequately sequestered with respect to the 

biosphere. Research regarding the impact of CO2 leaks on potable aquifers is 

focused on, 1) assessing geochemical outcomes of increased CO2 and their effects 

on drinking water quality, 2) determining the potential for widespread usage of 

shallow aquifer geochemistry for CO2 storage evaluation and, 3) identifying the 

parameters best suited for monitoring groundwater resources. 

The success of using shallow groundwater geochemistry as a tool for CO2 storage 

evaluation depends upon the ability to identify one or more geochemical 

parameters sensitive enough to provide a recognizable geochemical shift upon 

addition of exogenous CO2 to the aquifer. This requires a shift that is larger 

than normal background variability and is therefore detectable as an indicator 

of change. Widespread application of these methods in a variety of GS locations 

also necessitates that the type and magnitude of geochemical shift is similar or 

at least predictable in any geochemical environment even though processes and 

mineralogies differ widely among aquifers. 

Indeed the position of many researchers is that a predictable consequence of 

input of CO2 into a dilute aquifer is an increase in dissolved inorganic carbon 

(DIC) as alkalinity, H2CO3or HCO3?, a decrease in pH, and mobilization of 

cations including toxic metals from mineral dissolution and desorption reactions 

(Assayag et. al., 2009; Apps, et. al., 2009; Carroll et. al., 2009; Wang and 

Jaffe, 2004). A popular suggestion is that these parameters are therefore 

suitable for monitoring groundwater resources. The results of the SACROC ground 

water study, which is the only field study to date of potable water at a largescale industrial CO2 storage analogue, give strong evidence against such 

assumptions. At SACROC, natural and man-induced processes that are common in 

many shallow aquifers have created; 1) a geochemical system that is more complex 

and reacts differently to CO2 than the simple system put forth by previous 

researchers, and 2) a background variability that would mask even a relatively 

large-scale exogenous CO2 input. The implications are that GS monitoring 

strategies using natural groundwater constituents must, at the very least, be 

site-specific and may not be useful at all owing to the variability and 

185
complexity of groundwater systems. 

Research Objectives and Approach 

To test methodologies for CO2 storage evaluation using shallow aquifers, we 

targeted a potable water source (Dockum aquifer) above a long-duration (>35 

years) large-scale (~250 km2) engineered CO2 injection site in west Texas. The 

SACROC oil field in Scurry County, TX, currently operated by Kinder Morgan has 

injected CO2 for enhanced oil recovery (EOR) since 1972 with approximately 50% 

recovery and recycling of injected CO2. This site provides the opportunity to 

investigate (1) if CO2 from over 35 years of injection can be identified in the 

shallow aquifer and (2) if groundwater chemistry can be effectively used as a 

monitoring tool at sequestration sites. 

To accomplish our objectives, we compared the groundwater geochemistry of 

samples collected in the area of CO2 injection (inside SACROC) to that of 

groundwater samples collected from areas that have not experienced CO2 injection 

(outside SACROC). In addition, we utilize regional historical data from the 

Texas Water Development Board (TWDB) collected either prior to or spatially 

removed from any influence of engineered CO2 injection from the SACROC or nearby 

Sharon Ridge Field to establish regional background variability in geochemistry. 

Geochemical perturbations lying outside the normal range of groundwater 

variability could signal anthropogenic CO2 input. In addition, we use stable 

carbon isotopes to source-identify dissolved CO2 to distinguish natural 

microbial inputs from anthropogenic ones. 

Methods 

Approximately 113 fresh to slightly saline groundwater samples within Triassicage Dockum and 8 samples from Permian-age evaporite deposits were collected from 

60 private water wells (50- to 500-ft?deep) and 1 spring during five water 

sampling trips, June 2006 - November 2008. Samples were analyzed in the field 

for alkalinity, dissolved oxygen, conductivity, pH, and temperature and in the 

laboratory for major cations and anions, trace elements, delta^13carbon,^18 O, 

and 2^Hydrogen H isotopes, dissolved organic and inorganic carbon, and headspace 

gases. Ten samples of brines co-produced by Kinder Morgan from the 6,000- to 

7,000-ft injection/production zone were also analyzed for these parameters. 

Additional geochemical data on co-produced brines were provided by Kinder Morgan 

and historical records for Dockum and Permian water geochemistry collected by 

the Texas Water Development Board between 1936 and 2008 from eight Texas 

counties were also added to the data set. Carbon isotopes of CO2 being injected 

186
for enhanced oil recovery, soil organic matter, and soil carbonate from Dockum 

cores were collected and analyzed for delta^13carbon Two samples of Dockum core 

from depth intervals of 450?460 ft and 370-380 ft were examined for mineralogy 

using SEM with aid of an energy dispersive X- ray system which can identify 

chemical composition of point area. 

Results and Discussion 

Consideration of regional geology and stratigraphy of the area, geochemical 

trends of collected data, and past and present farming and pre-CO2-EOR 

practices, was used to identify background geochemical influences on Dockum 

geochemistry. The major influences are; 1) mixing of Dockum groundwater with 

underlying Permian evaporite waters along a well? documented Permian dissolution 

zone (i.e., Dutton, 1989), 2) leaching into the Dockum of historically?produced 

brine formerly stored in unlined surface pits, 3) temporal geochemical 

variations related to Dockum aquifer pumping and local irrigation practices, 4) 

groundwater interaction with spatially and compositionally variable 

stratigraphic units, 5) cation exchange, and 6) dedolomitization. Potential 

sources of CO2 in Dockum groundwater were identified as; 1) CO2 injected into 

the production zone, 2) CO2 produced from microbial activities, and 3) degassing 

from rock-water reactions. 

The findings at SACROC are pertinent to a wide variety of hydrogeologic 

environments where GS sites may be implemented and therefore must be considered 

when developing a near? surface monitoring program. They illustrate the 

importance of understanding hydrochemical context and background variability to 

implementing monitoring protocol. These points are further illustrated below: 

1. Geochemical Context - The geochemical driving forces of the hydrochemical 

system must be defined before the consequences of CO2 input can be predicted. In 

the Dockum aquifer, as well as in many other aquifers, mixing of concentrated 

waters (in this case Na-Cl brines with cation exchange and Ca-SO4 Permian 

evaporite waters) drives dedolomitization. Dissolution of dolomite and 

precipitation of calcite (dedolomitization) fueled by calcium ions is widely 

documented and common in many hydrologic systems (Pacheco and Szocs, 2006; Back 

and Baedecker, 1989; Back et. al., 1979; Plummer and Back, 1980; Hanshaw and 

Back, 1985) and creates a significantly different carbonate environment than 

that of simple calcite dissolution. Whereby calcite dissolution is driven by 

CO2, dedolomitization is driven by calcium ions which create undersaturation of 

the system with respect to dolomite and oversaturation with respect to calcite. 

Input of CO2 into these very different systems has been modeled to produce very 

187
different outcomes. In the simple system, DIC increases with increases in the 

partial pressures of CO2 (PCO2) as previous researchers have predicted. However, 

in the case of dedolomitization, evolution of groundwater proceeds towards lower 

HCO3- concentrations. Increases in PCO2 simply shift this overall trend towards 

higher HCO3- but retain the same overall evolutionary trajectories. This complex 

geochemical reaction would yield inaccurate conclusions if dedolomitization had 

not been identified as a dominant process. 

2. Background variability - Because CO2 exists naturally in an aquifer, stable 

carbon isotopes were used to determine if exogenous CO2 in the Dockum aquifer 

could be distinguished from natural CO2. Stable carbon isotope ratios of various 

carbon sources in the system, the PHREEQC numerical code, and isotope mass 

balance equations were used to; 1) model isotopic trends during dedolomitization 

under open and closed systems and, 2) identify the most likely source of CO2 in 

the Dockum aquifer. We modeled carbon isotopic and DIC trends during 

dedolomitization in open? and closed?systems with and without injectate and 

microbial CO2 input. Whereas isotopic trends for calcite dissolution are 

straightforward, isotopic trends during dedolomitization are complex. When 

coupled with high background geochemical variability such as in the Dockum 

aquifer system, stable carbon isotopes do not yield definitive results. Hence 

stable carbon isotopes do not appear to be the best tool for positive 

identification of injectate CO2 in the Dockum aquifer - and possibly in other 

complex aquifer systems as well. 

Conclusions 

Based on a field study and modeling of a long-running, large?scale engineered 

CO2-EOR site, we conclude that shallow aquifer geochemistry has limited 

applicability for monitoring permanence of CO2 storage at GS sites. Many natural 

and man-induced factors create hydrochemical variability that may mask the 

effects of CO2 input in common hydrogeologic environments. Detailed costly 

studies of each geochemical system would be necessary to assure that 

interpretations are correct. Assumptions about CO2 leakage formed by observation 

of geochemical parameters without knowledge of controlling geochemical processes 

would lead to incorrect conclusions. 

References 

Apps, J. A., Zhang, Y., Zheng, L., Xu, T., Birkholzer, J.T., 2009, 

Identification of thermodynamic controls defining the concentrations of 

hazardous elements in potable ground waters and the potential impact of 

188
increasing carbon dioxide partial pressure. Energy Procedia 1(1): 1917-1924. 

Assayag, N., Matter, J., Ader, M., Goldberg, D., and Agrinier, P., 2009, 

Water?rock interactions during a CO2 injection field-test: Implications on host 

rock dissolution and alteration effects. Chemical Geology 265(1?2): 227-235. 

Back, W., Hanshaw, B.B., Pyle, T.E. Plummer, L.N., and Weidie A.E., 1979, 

Geochemical significance of groundwater discharge and carbonate solution to the 

formation of Caleta Xel Ha, Quintana Roo, Mexico. Water Resources Research, 

15(6): 1521–1535. 

Back, W. and Baedecker, M. J., 1989, Chemical hydrogeology in natural and 

contaminated environments. Journal of Hydrology, 106(1?2): 1?28. 

Back, W., Hanshaw, B.B., Plummer, L.N., Rahn, P.H., Rightmire, C.T., and Rubin, 

M., 1983, Process and rate of dedolomitization: mass transfer and 14C dating in 

a regional carbonate aquifer. Geological Society of America Bulletin, v. 94, p. 

1415?1429. 

Carroll, S., Hao, Y, and Aines, R., 2008, Geochemical detection of CO2 in dilute 

aquifers. Geochemical Transactions, 10: 4. 

Dutton, A.R., 1989, Hydrogeochemical processes involved in salt-dissolution 

zones, Texas panhandle, U.S.A.: Hydrological Processes, v. 3, p. 75?89. 

Hanshaw, B. B. and Back, W., 1985, Deciphering hydrological systems by means of 

geochemical processes. Hydrological Sciences Journal, 30(2): 257?271. 

Pacheco, F. A. L. and Szocs, T., 2006, Dedolomitization reactions driven by 

anthropogenic activity on loessy sediments, SW Hungary. Applied Geochemistry 

21(4): 614?631. 

Plummer, L. N. and Back, W., 1980, The mass balance approach; application to 

interpreting the chemical evolution of hydrologic systems. Am J Sci 280(2): 

130?142. 

Romanak, K. D., Smyth, R. C., Yang, C., and Hovorka, S. D., 2009, Modeling 

shallow groundwater geochemistry and carbon isotopes: test of methodology for 

CO2 storage evaluation at an EOR site, West Texas, USA (abs.): Eos, v. 90, no. 

22, Abstract V13C?03. 

189
Romanak, K. D., and Smyth, R. C., 2008, Geochemical effects of CO2-enhanced oil 

recovery on the shallow Dockum aquifer, west Texas (abs.), in 7th Annual 

Conference on Carbon Capture & Sequestration, May 5th-8th, 2008, Pittsburgh, 

Pennsylvania. 

Smyth, R. C., Hovorka, S. D., Lu, J., Romanak, K. D., Partin, J. W., Wong, 

Corinne, and Yang, C., 2009, Assessing risk to fresh water resources from 

long term CO2 injection-laboratory and field studies: Energy Procedia, v. 1, 

p. 1957?1964. 

Wang, S. and Jaffe, P.R., 2004, Dissolution of a mineral phase in potable 

aquifers due to CO2 releases from deep formations; effect of dissolution 

kinetics. Energy Conversion and Management 45(18?19): 2833?2848. 

Individual Response: EPA has reviewed the paper on “Recent results of the SACROC Groundwater 

Geochemistry Study.” EPA has been monitoring the progress at SACROC, among other GS projects. 

EPA acknowledges the submittal and will continue to review studies related to the evaluation of field 

results and the limitations of sampling and analysis, as well as the limitations of modeling. EPA intends 

to continue to collect data on GS and to incorporate such data and information as it implements its 

adaptive approach to the GS rulemaking to incorporate new research, data, and information about GS. 

For more information on the adaptive approach, see the responses to comments on the proposed rule 

in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Changbing Yang 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG) 

EPA Letter ID: 0371 

EPA Comment ID: 27948 

Comment: It is of fundamental importance that water-rock reactions be taken into account 

in the interpretation of ground water chemistry. Not considering the rock 

contributions to the rockwater- CO2 reactive system can lead to incorrect 

extrapolations and overemphasize the risk to water. 

Conclusions of modeling exercises must also be seriously weighted by the 

190
soundness of the model assumptions. For example, we think that the role of 

sulfides in terms of risk to water as a consequence of CO2 leakage in the report 

of Birkholzer et al. (2008) has been overemphasized, as these species are not 

the minerals commonly observed in fresh-water aquifers. 

The importance of considering rock-water interaction when studying potential 

impacts of geological CO2 sequestration on drinking water resources 

Changbing Yang, Jean-Philippe Nicot, Rebecca C. Smyth, Katherine D. Romanak, and 

Susan D. Hovorka 

Summary 

It is of fundamental importance that water-rock reactions be taken into account 

in the interpretation of ground water chemistry. Not considering the rock 

contributions to the rock-water-CO2 reactive system can lead to incorrect 

extrapolations and overemphasize the risk to water. 

Conclusions of modeling exercises must also be seriously weighted by the 

soundness of the model assumptions. For example, we think that the role of 

sulfides in terms of risk to water as a consequence of CO2 leakage in the report 

of Birkholzer et al. (2008) has been overemphasized, as these species are not 

the minerals commonly observed in fresh-water aquifers. 

Introduction 

Researchers from the Bureau of Economic Geology (BEG) at the University of Texas 

at Austin are conducting experimental and modeling studies relevant to geologic 

sequestration of CO2 (CO2GS) with specific regard to potential impacts to 

shallow groundwater resources. In addition, BEG researchers have recently 

completed a field- based groundwater sampling study at the SACROC oilfield in 

west Texas and are continuing research on CO2GS at the Cranfield oilfield in 

Mississippi. Other researchers in the field of geologic carbon sequestration 

have recently published work on potential impacts to water resources as a result 

of CO2 injection directly into deep brine formations, or by accidental release 

of injectate CO2 into drinking water resources either through laboratory 

experiments or groundwater modeling studies. 

Themes we want to emphasize as being critical to studies of potential impacts to 

drinking water resources from CO2 injection are: 

191
- CO2 occurs naturally in shallow aquifers. CO2 concentrations in a single 

aquifer can vary temporally and spatially as a result of agricultural and 

industrial practices. For example, Scanlon et al. (2005, 2007) have documented 

enhanced recharge from land use changes. Enhanced recharge of groundwater 

through the vadose zone can potentially change CO2 concentrations in the 

saturated zone. 

- The capacity for carbonate minerals (carbonate rocks and carbonate cement in 

clastic rocks) to buffering changes in pH with influx of CO2 is under 

represented in the literature (i.e. Carroll et al., 2009). An exception to this 

statement is Keating et al. (2009) who documented nicely the buffering capacity 

of carbonate cement in a high-CO2 concentration natural analog system in New 

Mexico. 

- Realistic rock-water reactions are critical to accurate prediction of impacts 

to groundwater as a result of CO2 injection (numerous articles referenced 

herein). For example, Romanak et al. (in preparation) have also documented the 

importance of carbonates but in a more complex fashion through the incongruent 

dissolution of dolomite as a process dominating the hydrochemistry of the Dockum 

aquifer that overlies the SACROC oilfield in west Texas. 

The following text is a review of recently published studies on potential 

impacts to groundwater from GS with some examples from BEG’s on-going and soon 

to be published work. We start by citing published work on the importance of 

rock-water interactions in both deep and shallow aquifers for interpreting 

results of groundwater modeling. We then focus on one specific study (Birkholzer 

et al., 2008) that has been completed by researchers at the Lawrence Berkeley 

National Laboratories (LBNL). 

CO2-water-rock interactions discussed in literature 

Rock-water reactions are ubiquitous in groundwater systems and cannot be 

excluded from models used to predict impacts to groundwater from introduction of 

CO2. Work of Kaszuba et al. (2003) concludes that because of the importance of 

rock-water reactions in potential geologic sequestration systems, much more than 

simple aqueous dissolution of CO2 in water must be factored into any realistic 

model of potential impacts to deep formation fluids or freshwater aquifers from 

introduction of anthropogenic CO2. 

Earlier work by Zhu and Burden (2001) states that the complexity of aquifer 

192
fluid chemistry is defined by the degree of interaction with aquifer mineralogy, 

which includes solid matrix, grain-coatings and colloids. They are critical of 

groundwater modeling efforts that only consider pore-fluid compositions and 

ignore or greatly simplify aquifer mineralogy. Conclusions from Zhu and Burden 

(2001) are that contaminant fate and transport model predictions depend upon 

mineral composition of the aquifer. In fact, they state that the amount of 

calcite in the aquifer matrix determines the distance of contaminant plume 

migration. 

Wigand et al. (2008) go on to state that not only does introduction of 

supercritical CO2 into geologic systems affect brine composition through aqueous 

dissolution, it also affects the intensity of rock-water interactions. The 

phenomenon of increased rock-water interaction with increase in dissolved CO2 in 

brine is becoming common knowledge through DOE/NETL- and EPA-sponsored research 

on geologic sequestration (i.e., Keating et al. 2009). 

Review of LBNL shallow groundwater modeling LBNL (Birkholzer et al., 2008) 

evaluated mobilization of a set of trace elements (called hazardous constituents 

in the report [Footnote1]), such as arsenic, barium, cadmium, mercury, lead, 

uranium and zinc from a set of mineral species that may potentially be mobilized 

in the event of CO2 leak from the deep storage reservoirs using a comprehensive 

computational model. The mineral assemblages in the aquifer rocks were selected 

indirectly upon evaluation of 38,000 groundwater samples from aquifers 

throughout the United States, retrieved from the Unites States National Water 

Information System (NWIS). The report concluded that some trace elements may be 

mobilized and exceed the maximum contamination levels (MCL) resulting from 

enhanced dissolution of the mineral assemblages caused by CO2 intrusion into 

shallow groundwater aquifers. However, the model results rely on a fundamental 

assumption with large uncertainties in model parameters. We disagree with the 

assumption for constructing the EQ3/6 models and the methodology they used for 

investigating mobilization of trace elements from the aquifer rocks. We believe 

that this report illustrates the trappings of solely using groundwater 

compositions to estimate impact of CO2 on the system. 

[Footnote 1]: We disagree with the term "hazardous constituents" used in the 

Birkholzer et al., (2008) report because the trace elements occur in groundwater 

naturally even if their concentrations may increase owing to CO2 intrusion. 

The fundamental assumption in the Birkholzer et al. (2008) report for 

constructing the EQ3/6 models is that mobilization of trace elements is mainly 

dominated by enhanced dissolution of a set of specific mineral assemblages (for 

193
instances, sulfides in Table 3.6, p37 in the report). This set of specific 

mineral assemblages was selected from mineralogical analysis of coal seam 

aquifers, which formed in very strong reducing environments. Based on such an 

assumption, the authors calculated saturation indices of the selected mineral 

assemblages over chemical analyses of 38000 groundwater samples and determined 

whether a specific mineral phase would be present in a rock in equilibrium with 

the water sample. In a second step, assuming this phase is present, the authors 

computed the amount of trace elements that could be released under addition of 

CO2. This assumption is unreasonable and not well supported at all in the 

literature. There are many other factors that could affect mobilization of the 

tracer elements, such as aqueous complexation (by ligands), ad/desorption from 

metal oxide and clay surfaces, and solid solutions in common minerals 

(carbonates, feldspars, and clay minerals). For instance, behavior and 

contribution of arsenic in natural water are related to MeOx (either simple 

desorption in oxidizing conditions or reducing conditions) (for example, Smedley 

and Kinniburgh, 2002, Scanlon et al. 2009). 

BEG researchers did a set of batch experiments by reacting rock samples taken 

from major aquifers in Texas with water and CO2 gas at a pressure of 1 atm (Lu 

et al., 2009, Smith etal. 2009). They found that concentrations of some trace 

elements may be elevated after CO2 intrusion, such as arsenic (Figure 1). 

However, no evidences of XRD and SEM analysis indicated that arsenopyrite 

existed in the rock samples. Lead, which according to the Birkholzer (2008) 

could be the most problematic element after CO2 intrusion, however, is nondetectable in the 10 batch experiments. Of the 114 analyses of potable 

groundwater in the vicinity of the SACROC oilfield in west Texas, 100 samples 

(88% of the total samples) had Pb concentrations below a detection limit of 

0.0002 milligrams per liter (mg/L) (Smyth et al., in preparation). Our 

experiences indicate that Pb in drinking water resources commonly comes from 

corrosion of submersible water pumps and accompanying conduit pipes and not from 

the aquifer rocks. 

[PLEASE SEE P. 4 of EPA-HQ-OW-2008-0390-0371.PDF FOR IMAGE OF FIGURE 1] 

Figure 1: Evolution of arsenic concentration in 

four batch experiments (time 0 represents introduction of CO2 into the batch 

reactor) 

In conclusion, the methodology employed in the Birkholzer (2008) report on 

potential impacts of CO2 addition to shallow groundwater resources by using only 

numerical modeling techniques is questionable and may be misleading if the 

194
controlling minerals/or controlling phases assumed in the numerical models are 

not the right ones. In addition, large uncertainties in the model parameters, 

such as Eh values and solubility constants may lead to wrong conclusions. 

Regulations of CCS based on such conclusions drawn from the model results 

presented in the Birkholzer (2008) report could be biased and may be impractical 

when applied to actual sites. 

References 

Birkholzer, J., 2008, Research project on CO2 geological storage and groundwater 

resources: water quality effects caused by CO2 intrusion into shallow 

groundwater: Technical Report LBNL-1251E, 352p. 

Carroll, S., Hao, Y., and Aines, R., 2009, Geochemical detection of carbon 

dioxide in dilute aquifers: Geochemical Transactions 10:4; doi: 

10.1186/1467-4866-10-4. 

Kaszuba, J.P., Janecky, D. R., Snow, M.G., 2003, Carbon dioxide reaction 

processes in a model brine aquifer at 200 C and 200 bars: implications for 

geologic sequestration of carbon: Applied Geochemistry, v. 18, p. 1065-1080. 

Keating, HE, Julianna Fessenden, Nancy Kanjorski, Daniel J. Koning, and Rajesh 

Pawar, 2009, The impact of CO2 on shallow groundwater chemistry: observations at 

a natural analog site and implications for carbon sequestration, under review. 

Lu, J., Partin JW, Hovorka, SD, Wong, Corinne Wong (2009) Potential risks to 

fresh- water resources as a result of leakage from CO2 geological storage-a 

atch-reaction experiment, Environmental Geology, under review. 

Scanlon BR, Reedy RC, Stonestrom DA, Prudic DE, Dennehy KF, 2005, Impact of land 

use and land cover change on groundwater recharge and quality in the 

southwestern USA. Global Change Biol 11: 1577-1593 

Scanlon BR, Reedy RC, Tachovsky JA, 2007, Semiarid unsaturated zone chloride 

profiles: Archives of past land use change impacts on water resources in the 

southern High Plains, United States. Water Resour Res 43: Art. No. W06423 

Scanlon, B. R., Nicot, J. -P., Reedy, R. C., Kurtzman, D., Mukherjee, A., and 

Nordstrom, D. K., 2009, Elevated naturally occurring arsenic in a semiarid 

195
oxidizing system: Southern High Plains aquifer, Texas, USA: Applied 

Geochemistry, doi:10.1016/j.apgeochem.2009.08.0004. 

Shiraki, M., and Dunn, T.L., 2000, Experimental study on water-rock interactions 

during CO2 flooding in the Tensleep Formation, Wyoming, U.S.A.:Applied 

Geochemistry, v. 15, p. 265-279. 

Smedley, P.L., Kinniburgh, D.G., 2002. A review of the source, behaviour and 

distribution of arsenic in natural waters. Appl. Geochem. 17, 517-568. 

Smyth, R., S. Hovorka, J. Lu, K. Romanak, J. Partin, C. Wong, C. Yang, 

2009, Assessing risk to fresh water resources from long term CO2 injection - 

laboratory and field studies, Energy Procedia, p1957-1964. 

Smyth, R., S. Hovorka, J. Lu, K. Romanak, J. Partin, C. Wong, and C. Yang, 

2009, Hydrogeology of Dockum groundwater near the SACROC CO2 EOR oilfield, 

Scurry County, Texas, in preparation. 

Wigand, M., Carey, J.W., Schutt, H., Spangenberg, E., and Erzinger, J., 2008, 

Geochemical effects of CO2 sequestration in sandstones under simulated in situ 

conditions of deep saline aquifers: Applied Geochemistry, v. 23, p. 2735-2745. 

Zhu, C. and Burden, D. S., 2001, Mineralogical compositions of aquifer matrix as 

necessary initial conditions in reactive contaminant transport models: 

Contaminant Hydrology, v. 51, p. 145-161. 

Individual Response: EPA has reviewed the paper on “The importance of considering rock-water 

interaction when studying potential impacts of geological CO2 sequestration on drinking water 

resources.” EPA acknowledges the submittal and will continue to review studies related to the 

evaluation of field results and the limitations of sampling and analysis, as well as the limitations of 

modeling. EPA adds that is has been monitoring the progress at SACROC, among other GS projects. 

EPA intends to continue to collect data on GS and to incorporate such data and information as it 

implements its adaptive approach to the GS rulemaking to incorporate new research, data, and 

information about GS. For more information on the adaptive approach, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

196
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca C. Smyth 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology, Jackson 

School of Geosciences, Gulf Coast Carbon Center 

EPA Letter ID: 0377 

EPA Comment ID: 28180 

Comment: Over 3 trillion standard cubic feet (TCF) or 150 million metric tons of CO2 have 

been injected for enhanced oil recovery (EOR) at the SACROC oilfield in west 

Texas since 1972. Roughly half of the injected CO2 has been produced and 

reinjected as part of a recycling effort; an estimated 35 million tons is 

permanently sequestered in the subsurface at SACROC. Clearly this is a large 

scale CO2 injection site. As with the other four CO2 injection sites referenced 

in Section II of this Notice, there has been no documented leakage of CO2 at 

SACROC. 

The attached document (Smyth et al., 2009, Assessing risk to fresh water 

resources from long term CO2 injection; Energy Procedia 1, p. 1957-1964) details 

some results of the DOE/NETL-funded (through SWP) field study of drinking water 

resources over SACROC. This study, which has been conducted by researchers of 

the Bureau of Economic Geology, Jackson School of Geosciences and The University 

of Texas at Austin, satisfies the LBNL suggestion that field studies be 

conducted to assess impacts to drinking water resources from CO2 injection. 

Conclusions from this study are included in several comments being submitted by 

BEG researchers. 

In summary, based upon 114 samples from 60 wells and one spring of Dockum 

aquifer water collected in an ~250 km2 area centered on SACROC, we fail to 

detect any impacts to drinking water resources as a result of anthropogenic CO2 

injection. Concentrations of As, Cd, F-, NO3-N, Se, Al, Cl-, Mn, SO42-, and TDS 

do exceed drinking water standards in some wells in Scurry County; however, most 

of these wells are outside of and at some distance away from SACROC. 

Results of the BEG study are consistent with the statement in the Supplemental 

Information Section C Introduction that the oil and gas industry has been safely 

injecting CO2 for enhanced oil and gas recovery for decades. 

Individual Response: EPA has reviewed the paper “Assessing risk to fresh water resources from long 

term CO2 injection – laboratory and field studies.” EPA acknowledges the submittal and will continue 

197
to review studies related to the evaluation of actual field results and the limitations of sampling and 

analysis, as well as the limitations of modeling. EPA adds that is has been monitoring the progress at 

SACROC, among other GS projects. EPA intends to continue to collect data on GS and to incorporate 

such data and information as it implements its adaptive approach to the GS rulemaking to incorporate 

new research, data, and information about GS. For more information on the adaptive approach, see 

the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca C. Smyth 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology, Jackson 

School of Geosciences, Gulf Coast Carbon Center 

EPA Letter ID: 0379 

EPA Comment ID: 28184 

Comment: Over 3 trillion standard cubic feet (TCF) or 150 million metric tons of 

CO2 have been injected for enhanced oil recovery (EOR) at the SACROC oilfield in 

west Texas since 1972. Roughly half of the injected CO2 has been produced and 

reinjected as part of a recycling effort; an estimated 35 million tons is 

permanently sequestered in the subsurface at SACROC. Clearly this is a large 

scale CO2 injection site. As with the other four CO2 injection sites referenced 

in Section II of this Notice, there has been no documented leakage of CO2 at 

SACROC. 

The attached document is a status report submitted to EPA Region 6 offices in 

Dallas, TX in April 2009. This report summarizes DOE/NETL-funded, through the 

Southwest Regional Carbon Sequestration Partnership (SWP), research at SACROC. 

Objectives of the combined research efforts of the Bureau of Economic Geology, 

Los Alamos National Laboratory, New Mexico Tech, University of Pittsburgh, and 

University of Utah are to (1) assess potential impacts to the shallow subsurface 

over SACROC, (2) model the fate of CO2 injected into the subsurface at SACROC, 

and (3) use geophysical methods to image the ~35 million tons of CO2 assumed to 

be trapped in the subsurface. 

Please refer to the PDF or see further down below for the text of the attachment. 

Individual Response: EPA has reviewed the status report on the SACROC project. EPA acknowledges 

the submittal and will continue to review studies related to the evaluation of actual field results and 

198
the limitations of sampling and analysis, as well as the limitations of modeling. EPA adds that is has 

been monitoring the progress at SACROC, among other GS projects. EPA intends to continue to collect 

data on GS and to incorporate such data and information as it implements its adaptive approach to 

the GS rulemaking to incorporate new research, data, and information about GS. For more information 

on the adaptive approach, see the responses to comments on the proposed rule in the rulemaking 

docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jiemin Lu 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG), Gulf 

Coast Carbon Center (GCCC) 

EPA Letter ID: 0387 

EPA Comment ID: 28185 

Comment: I am commenting on Document ID EPA-HQ-OW-2008-0390-0297 

III. Research, Data Analysis, and Findings 

C. Lawrence Berkeley National Laboratory (LBNL) Studies 

1. Ground Water Quality Changes Related to the Mobilization of Trace Elements 

Gulf Coast Carbon Center at Bureau of Economic Geology, University of Texas at 

Austin, conducted a laboratory-batch experiment to investigate the range of CO2- 

leakage impact on groundwater quality of seven representative aquifers in the 

Gulf Coast region, USA, starting with representative sandstone aquifer rock 

samples. 

Experiment results suggest that carbonate minerals are the dominant contributor 

of changes in groundwater quality as a result of addition of CO2. Dissolution of 

dolomite and calcite, when they exist, caused the largest increase in 

concentrations of Ca, Mg, Mn, Ba and Sr. The latter three cations exist as trace 

elements in the carbonate minerals. 

Following CO2 input in the experiment, cations show different concentration 

trends, according to which, cations can be grouped into two categories. Type I 

199
cations?Ca, Mg, Si, K, Sr, Mn, Ba, Co, B, Zn?rapidly increased following initial 

CO2 flux and reached stable concentrations before the end of the experiment. 

Type II cations?Fe, Al, Mo, U, V, As, Cr, Cs, Rb, Ni and Cu?increased at the 

start of CO2 flux, but declined, in most cases, to levels lower than pre-CO2 

concentrations. 

Potential risks to drinking water quality are mostly related to Type I heavy 

metals such as Mn, Ba, Sr, Co, and Zn, which are associated with carbonate 

minerals. Type II cations, which appear to be related to desorption/adsorption, 

show limited impact on ground water quality. Anions showed no significant 

increases after introduction of CO2. Although rocks from high arsenic aquifers 

were included in the study, no risks related to increased sulfur, lead, or 

arsenic were observed in the study. 

Individual Response: EPA has reviewed the summary of research by the Bureau of Economic 

Geology on CO2-leakage impact on ground water quality of Gulf Coast aquifers. EPA acknowledges the 

submittal and will continue to review studies and field results and the limitations of sampling and 

analysis, as well as the limitations of modeling. EPA intends to continue to collect data on GS and to 

incorporate such data and information as it implements its adaptive approach to the GS rulemaking to 

incorporate new research, data, and information about GS. For more information on the adaptive 

approach, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-JUL-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jiemin Lu 

Commenter Organization: University of Texas at Austin, Bureau of Economic Geology (BEG), Gulf 

Coast Carbon Center (GCCC) 

EPA Letter ID: 0387 

EPA Comment ID: 28186 

Comment: The paper attached is in press with Environmental Earth Science. 

BELOW IS THE SUPPORTING DOCUMENT ENTITLED POTENTIAL RISKS TO FRESH-WATER 

200
RESOURCES AS A RESULT OF LEAKAGE FROM CO2 GEOLOGICAL STORAGE: A BATCH-REACTION 

EXPERIMENT 

Dear Editor, 

We submit the following paper: 'Potential risks to fresh-water resources as a 

result of leakage from CO2 geological storage-a batch-reaction experiment'. In 

the paper, we report results of a batch-reaction experiment of CO2 reacting with 

a range of aquifer host rocks. This paper will improve understanding of 

potential risks to groundwater resources overlying sites of CO2 geological 

storage if CO2 leakage occurs. It will also help design groundwater monitoring 

program. 

All the data and interpretation the paper present are original. There is no 

related prior published work. 

Regards 

Jiemin Lu 

Jiemin.lu@beg.utexas.edu Gulf Coast Carbon Center 

Bureau of Economic Geology 

Jackson School of Geosciences, 

The University of Texas at Austin 

P.O. Box X 

Austin, TX 78713 

USA 

Potential risks to fresh-water resources as a result of leakage from CO2 

geological storage-a batch-reaction experiment 

Jiemin Lu, Judson W. Partin, Susan D. Hovorka, Corinne Wong 

J. Lu, S. D. Hovorka 

Gulf Coast Carbon Center, Bureau of Economic Geology, Jackson School of 

201
Geosciences, The University of Texas at Austin, P.O. Box X, Austin, TX, 78713, 

USA 

J. W. Partin, C. Wong 

Department of Geological Sciences, Jackson School of Geosciences, The University 

of Texas at Austin, Austin, TX,78712, USA 

Corresponding author, J. Lu, Tel.: +1 512 475 9525; E-mail address: 

Jiemin.lu@beg.utexas.edu 

Abstract 

In assessing the feasibility of widespread deployment of CO2 geological storage, 

it is prudent to first assess potential consequences of an error or accident 

that could lead to CO2 leakage into groundwater resources above a sequestration 

interval. Information about the sensitivity of the groundwater system to 

introduction of CO2 is needed in order to design groundwater monitoring program. 

A laboratory-batch experiment was conducted to explore the range of CO2 impact 

on groundwater quality of a spectrum of representative aquifers, in the Gulf 

Coast region, USA. Results show that CO2 elevated concentrations of many cations 

within hours or days. Two types of cations were recognized according to their 

concentration trends. Type I cations-Ca, Mg, Si, K, Sr, Mn, Ba, Co, B, 

Zn-rapidly increased following initial CO2 flux and reached stable 

concentrations before the end of the experiment. Type II cations-Fe, Al, Mo, U, 

V, As, Cr, Cs, Rb, Ni and Cu-increased at the start of CO2 flux, but declined, 

in most cases, to levels lower than pre-CO2 concentrations. 

Dissolution of dolomite and calcite caused the largest increase in 

concentrations for Ca, Mg, Mn, Ba and Sr. Cation release rates decreased 

linearly as pH increased during mineral buffering. Experiment results suggest 

that carbonate minerals are the dominant contributor of changes in groundwater 

quality. Risk assessments of potential degradation of groundwater and monitoring 

strategies should focus on these fast-reacting minerals. Mobilization risk of 

Type II cations, however, may be self mitigated because adsorption occurs when 

pH rebounds. 

Key words: Carbon sequestration; CO2-rock-water reactions; carbonate 

dissolution; water contamination; groundwater monitoring 

1. Introduction 

202
Capture of anthropogenic CO2 emissions and storage in suitable subsurface 

geological formations has been recognized as an important method of mitigating 

greenhouse gas emissions (e.g., Baines and Worden 2004; Schrag 2007). A series 

of studies (Hovorka et al. 2006; Hovorka et al. 2009; Smyth et al. 2009) have 

focused on potential storage sites in the Gulf Coast region, which has both high 

need (high concentration of point-source industrial emission sites, such as 

power plants and refineries) and high opportunity (thick, well-known 

sequestration targets) . 

The Gulf Coast region relies heavily on fresh-water aquifers for its drinkingwater supply. Potential CO2 storage intervals, over 1.5 km deep, are well below 

these fresh-water aquifers. Prior to permitting for injection, a site is 

required to provide assurance of permanence of CO2 storage through proper site 

selection and injection management; however, it is also prudent to (1) define an 

effective monitoring strategy that will show that the site is performing 

correctly, (2) assess potential consequences of CO2 leakage should an error 

occur, and (3) plan for any mitigation needed to correct an error. In this study 

we consider the impact of CO2 leakage through an undetected flaw in the seal on 

groundwater resources above a sequestration interval. As well as assessing for 

risks to water, monitoring groundwater may be a valuable monitoring tool for 

demonstrating no leakage. An aquifer typically extends over a storage site and 

moves across the site under hydrologic gradient; it may be an excellent 

integrator that can be used to determine that no leakage occurred. 

Characterization of the signal by reaction of CO2 with aquifer rocks is needed 

to determine whether groundwater monitoring might be effective, as well as 

diagnostic of leakage detection. 

CO2 gas entering an aquifer will dissolve into and acidify the groundwater it 

comes in contact with. Decrease in pH may cause dissolution of minerals such as 

feldspar and carbonates (e.g., Gunter et al. 1993, 1997; Kirste et al. 2004): 

K-feldspar + 1.5 H2O + CO2 (g) -> K+ + 0.5 Kaolinite + 2 SiO2(aq) + HCO3 (1) 

Ca/Mg/FeCO3 + CO2(g) + H2O -> 2HCO3- + Ca^2+/Mg^+2/Fe^+2 (2) 

Such reactions will buffer pH and increase total dissolved solids and 

alkalinity, which are parameters considered in water-quality assessment. 

Increasing acidity can also affect sorption of ions onto grain-coat boundaries, 

which may enhance desorption of potentially hazardous trace metals (e.g., Yin et 

al. 1996; Bradl 2004; Wang and Jaffe 2004). Effects of additional CO2 on 

203
groundwater will be controlled by water-rock interactions, which will, in turn, 

depend on various mineralogical compositions of a wide range of aquifer host 

rocks. 

Most field studies that investigate mineral reactions related to high 

concentrations of CO2 have focused primarily on the injection zone at depths 

greater than 1 km (Gunter et al. 1993, 1997, 2004; Bachu et al. 1994, Rochelle 

et al. 2004; Karaka et al. 2006). Similarly, previous lab experiments (Pearce et 

al. 1996; Gunter et al. 1997; Kaszuba et al. 2003, 2005; Soong et al. 2004; 

Rosenbauer et al. 2005) and numerical simulations (Perkins and Gunter 1995; 

Gunter et al. 2000; Johnson et al. 2001; Perkins et al. 2002; Xu et al. 2004; 

Knauss et al. 2005; Palandri and Kharaka 2005; White et al. 2005; Xu et al. 

2005; Zerai et al. 2006) studying rock-brine-CO2 interactions are based on deep 

reservoir conditions in which temperature, pressure, and formation-water 

salinity are higher than near-surface conditions and CO2 is in a supercritical 

state (Knauss et al. 2005). In some instances (Karaka et al. 2006) these 

conditions are also strongly reducing and near saturation with methane. 

Whereas many potable waters that are high in CO2 occur naturally (e.g., the 

Perrier region of France), these rock-water aquifer systems have had a long time 

interval in which to equilibrate and may be an imperfect analog for short-term 

reactions that could result from accidental leakage of CO2 into an aquifer. 

Studies of introducing CO2 into shallow potable aquifer settings in which 

reactions may be different from those at depth are few. Most fresh-water 

aquifers are located generally at relatively shallow depths, typically less than 

300 m. Aquifer temperatures are typically similar to surface temperatures, lower 

than 25°C, and pressures are lower than 30 bar (Metcalfe 1996). CO2 occurs in a 

gaseous state under such conditions. The geochemical behavior of gaseous and 

supercritical CO2 differs and requires a different set of assumptions about its 

various interactions. 

Studies of UK groundwater suggest that change of pH and redox conditions induced 

by adding CO2 are dominant factors in groundwater chemistry (Edmunds et al. 

1989). Specifically, decrease in pH will cause carbonate dissolution to release 

major and trace elements in carbonate minerals, whereas redox potential (Eh) 

controls mobility of many elements, such Fe, Cu, V, U, and Cr. Variations in pH 

due to CO2 leakage will be a major control on metal sorption, which may affect 

mobility of heavy metals (Metcalfe 1996). Reactive transport simulations were 

recently conducted to investigate groundwater-quality change due to CO2 leakage 

(Wang and Jaffe 2004; Zheng et al. 2009). Results show that elevated CO2 levels 

in fresh-water aquifers can increase concentrations of trace metals to 

204
undesirable levels. Elevated Pb and As concentrations as a result of 

desorption/adsorption via surface complexation were identified. Modeling by 

Zheng et al. (2009) has suggested that trace amounts of minerals such as galena 

and other sulfate minerals containing hazardous metals are present under 

reducing conditions in aquifers and will dissolve. 

As a complement to several field studies (at SACROC, Scurry County, Texas; 

Cranfield, Adams County, Mississippi; and Brackenridge, Austin, Texas), this 

study uses laboratory batch-reaction experiments to investigate the consequences 

of CO2 leakage on shallow groundwater quality. The experiment was designed to 

assess the extent to which addition of CO2 could mobilize cations from the 

aquifer host rock, which could provide a lingering trace of this interaction and 

potentially cumulate to creat a threat to groundwater quality. By using a 

variety of aquifer-rock samples from the Gulf Coast region, we can get a 

perspective on the types of chemical changes in different aquifers, which can 

serve as background to and context into which to place single-aquifer-focused 

field studies. 

A variety of aquifer rocks were chosen to react with CO2 in the medium of fresh 

water in a series of reactors. Water in the reactors was sampled and analyzed 

with high temporal frequency during the reaction. Evidence of fluid-rock 

reactions is revealed in changes of water composition and mineral surface 

morphology. This study improves our understanding of CO2-water-mineral reactions 

in such environments and helps our assessment of contamination risks of CO2 

leakage to groundwater resources. Results can be used for sensitivity analysis 

in the design of field-testing experiments to determine whether any of 

constituents elevated in laboratory tests are detectable in groundwater that has 

or might have interacted with CO2. 

2. Methods 

2.1. Materials 

Nine samples representative of various aquifers throughout the Gulf Coast region 

were selected from the archived samples at the Core Research Center at the 

Bureau of Economic Geology, The University of Texas at Austin (UT). The samples 

represent, respectively, Dockum, Ogallala, Trinity, Carrizo-Wilcox, and Hickory 

aquifers in Texas and Cranfield (the shallowest) aquifer in Mississippi. A 

description of samples is given in Table 1 [p. 25 of pdf]. Unconsolidated 

samples were disaggregated by hand, and cemented samples were disaggregated 

using a rock hammer. 

205
Using natural rock samples allows for a realistic prediction of reactions when 

CO2 comes in contact with aquifer rocks. Unlike synthetic rock samples, however, 

natural rocks do not provide enough accurate mineral compositions to constrain 

the amount of mineral dissolution and precipitation. Therefore, this study will 

focus on water-chemistry changes, with time to interpret mineral reactions that 

occur during experiments. For this survey, because we did not have groundwater 

samples from aquifers, we had to equilibrate fresh water with aquifer samples to 

create a starting point. 

2.2. Experimental approach 

For each sample, about 95 g of disaggregated, unwashed rock samples were 

combined with 500 mL of deionized (DI) water (18 M.) in a wide-mouth 500-mL 

Erlenmeyer flask. To minimize the corrosiveness of the DI water, NaCl was added 

to approximate natural groundwater activity (~40 ppm Cl). Thus, the initial 

water:rock mass ratio was 5.3:1. The experiment was conducted in two phases. 

During the first 2 weeks, argon (Ar) gas was flushed through reactors to allow 

water-mineral systems to approach equilibrium with respect to major element 

concentrations. In the second 2-week phase, commercial-grade CO2 gas replaced Ar 

to flow through the reaction vessels. Water samples were taken to record changes 

in elemental concentrations during the study. Subsequent CO2 addition allows for 

comparison of reactions of rock-water systems with a minimally reactive gas (Ar) 

and with a reactive gas (CO2). Gas flow was regulated by a metering valve and a 

data-logger-controlled Solenoid valve that allowed 1 min of flow every 20 min, 

limiting evaporation while always keeping excess gas in the flask and in contact 

with rock and water. Each flask was sealed with a rubber stopper with two holes 

to facilitate airtight placement of inflow and outflow tubes into the flask. 

Inflow and outflow manifold systems were constructed so that reactors could be 

run simultaneously. The outflow manifold system was open to atmospheric 

pressure. The flask was agitated daily to maximize exposure of the rock sample 

to the water. 

To minimize microbial influences in the reaction vessels, glassware and brass 

fittings were acid cleaned and then heated to 250°C for 18 h. Also, to determine 

whether microbial populations nascent to the rock samples were involved in metal 

cycling, two samples (Dockum aquifer in Reactor B and Cranfield loess in Reactor 

D) were heated to 250°C for 18 h (Table 1 [p. 25 of pdf]). Both cooked and 

uncooked samples were used in the experiment. DI water used in the two cooked 

samples was passed through a 0.2-.m filter. To constrain system error in the 

experiment, a blank run was performed under the same conditions, but without a 

206
rock sample added to the flask. All 10 flasks were covered in aluminum foil to 

minimize photosynthetic activity. 

For the first 2 weeks, Ar gas was bubbled through the system. Ten water samples 

(2 mL) were taken at 1-, 5-, 12-h and 1-, 2-, 4-, 7-, 10-, 12-, and 14-d time 

intervals for cation analysis and acidified with 100 .l of 2% nitric acid. Water 

was sampled four times at 12-h, 4-, 10-and 14-d time intervals for analysis of 

major anions (SO4, Cl, F, Br, NO3, and PO4). After each sampling, gas was then 

left on for about 5 min to purge the flasks and ensure an excess of gas. Cation 

water samples were filtered using a 0.45-.m pore- size filter, and a 0.2-.m 

pore-size filter was used for anion samples. Analysis of major Ca, K, Mg, Na, 

and Si and minor Ag, Al, As, B, Ba, Bi, Ce, Co, Cd, Cr, Cs, Cu, Fe, La, Li, Mn, 

Mo, Ni, P, Pb, Rb, Sb, Se, Sn, Th, U, V, and Zn cations was done at UT on an 

Agilent 7500ce Quadrupole ICP-MS. The pH was measured using a multiparameter 

probe (Hanna Instruments 9828). 

After 2 weeks, the gas supply was switched from Ar to CO2. At this time, 70 mL 

of DI water was added to each reactor to replace the water that had been removed 

during the Ar run (dilution factor 1.14). Following the same procedures, another 

10 water samples were taken at 1-, 5-, and 12-h, and 1-, 2-, 4-, 7-, 10-, 12-, 

and 14-d time intervals for cation analysis. Each reactor was sampled at 12-h, 

4-d, and 15-d time intervals for major anion analysis (except bicarbonate). 

To define mineralogical composition of the samples, X-ray diffraction (XRD) was 

conducted on chosen core materials using a Phillips automated vertical scanning 

powder diffractometer. Samples were grounded using a Spex SamplePrep 8000M 

Mixer/Mill with a tungsten carbide ball mill. Quantitative analyses were not 

applied because resolution of the XRD method is thought to be too low to 

quantify compositional variation caused by mineral reactions. Achievable 

resolution of the XRD quantitative method is about 3% absolute error (Hillier 

2000; Lu 2008). Minor mineral phases with low abundance can be reactive in 

contact with CO2 and have important influence on water chemistry. This kind of 

resolution is insufficient to constrain water-rock reactions from the solid 

phase. 

A scanning electron microscope (SEM) with energy dispersive spectrometry (EDS) 

was therefore used to aid in identifying minerals and dissolution/precipitation 

features. Both original and reacted samples were examined. Samples 5 to 10 mm in 

diameter were mounted on planchets and coated with gold. Secondary electron 

images and the EDS spectrum were acquired. Reacted samples were dried at 80°C 

overnight before they were coated. 

207
3. Results 

3.1. Solid phases 

Table 1 summarizes mineral compositions of rock samples used. All samples are 

dominated by quartz. Other mineral phases include albite, K-feldspar, carbonate 

minerals, illite/smectite, and kaolinite. The Dockum sample used in Reactors A 

and B contains dolomite; the Reactor I sample contains both calcite and 

dolomite. Note that dolomite in Cranfield loess used in Reactors C and D and 

kaolinite in the samples of Reactors G and H were not detected by XRD but were 

revealed by SEM analysis. 

Determining mineral reactions of feldspar and quartz based on mineral morphology 

proved not possible. Feldspar (K-feldspar and plagioclase) and quartz show 

abundant dissolution features in both original and reacted samples (Fig. 1a 

[page 27 of pdf]). Mineral grains that are not corroded show a thin clay coating 

on the surface. It is difficult to decide whether dissolution occurred during 

the experiment or during burial before the experiment. No evidence of 

precipitation was found in reacted samples either. 

Identifying clay mineral reactions in the samples is even more difficult. Illite 

and smectite, the most abundant clay minerals in the samples, occur as porefilling, pore-lining, and grain-coating habits. Kaolinite is present in Samples 

G and H in the form of euhedral booklets (Fig. 1b [page 28 of pdf]), which 

partly fill the pores. All these clay habits were observed in both pre-and 

postexperiment samples in similar proportion, making it inconclusive whether 

dissolution/precipitation occurred during the experiment. 

The most important mineral reaction determined by SEM analyses was dolomite 

dissolution in Reactors A, B, C, and D. The Dockum Formation sample from Randall 

County, Texas, used in Reactors A and B contains about 15% dolomite. In the 

original sample, dolomite occurred as fresh-looking rhombs with smooth surfaces 

(Fig. 1c [page 29 of pdf]). In the reacted samples, however, most dolomite 

crystals, especially the larger ones, were severely corroded or pitted with 

holes on the surface (Fig. 1d, e [pages 30 and 31 of pdf]). These features 

unambiguously pointed to dolomite dissolution. In reacted samples, patchy clay 

minerals, mostly smectite, were scattered on the once-smooth dolomite surfacesthe only SEM evidence to suggest clay precipitation during the experiment. 

3.2. Water chemistry 

208
Measured ion concentrations of each reactor were subtracted using counterpart 

measurements of the blank reactor. Such subtraction reduces contamination 

effects of the system, and Na and Cl are normalized as the amount of NaCl added 

at the beginning of the experiment is subtracted. The detailed results can be 

found in online background dataset. 

Major cations in the water, including Na, K, Ca, Mg, Si, Sr, Ba, Mn, and B, 

showed rapid increase in concentrations within the first day of the experiment 

(Fig. 2 [p. 32-33 of pdf]). These elements stabilized toward the end of the Ar 

run. 

In Reactors A-D, F, and H, introduction of CO2 resulted in rapid, large changes 

in water composition (Fig. 2a-d, f, and h). Compositional changes occurred 

within hours to days after introduction of CO2. Concentrations of Ca, Mg, K, Si, 

Fe, Al, Mn, Sr, and Ba were elevated. Concentrations of some (e.g., Ca, Mg, Mn, 

Fe, Sr, and Ba) increased by as much as two orders of magnitude, whereas K and 

Si experienced smaller increases. Following the initial rapid increase, cation 

release slowed. Most cations stabilized before the end of the experiment, except 

for Fe, Al, and trace elements such as Cr, Cu, Mo, U, V, etc. Stabilization of 

major cations suggests that the systems reached approximate equilibrium. In 

Reactors E, G, and I, addition of CO2 did not cause significant change in water 

composition beyond small fluctuations following initial introduction of CO2. 

Dilution due to the added 70 mL of DI water at the start of the CO2 period was 

evident in some cations, e.g., Na, K, B, and Si. Their concentrations clearly 

decreased during the first sampling interval following dilution. K and Si 

concentrations rebounded during later sample intervals and exceeded pre-CO2 

levels, but Na and B concentrations mostly remained lower than predilution 

levels. Other elements also occasionally showed concentration decrease due to 

dilution, but it was masked by rapid increase (e.g., Mg) or large fluctuations. 

We identified two types of cation behavior in response to CO2 from concentration 

trends (Table 2 [p. 26 of pdf]). Type I cations experienced rapid increases in 

concentration following initial introduction of CO2 and a gradual increase to 

stable concentrations before the end of the experiment. This group includes Ca, 

Mg, Si, K, Sr, Mn, Ba, Co, and Zn. Type II cations, which include Fe, Al, Mo, U, 

V, As, Cr, Cs, Rb, Ni, and Cu, also rapidly increased in concentration after 

introduction of CO2, but decreased and/or displayed concentration fluctuations 

through the end of the experiment. Final concentrations of most Type II cations 

are lower than pre-CO2 levels. 

209
As expected with the dissolution of CO2 into water, pH rapidly decreased 

following introduction of CO2 in all reactors (except Reactor G) (Fig. 3 [p. 34 

of pdf]). Initial decrease in pH was followed by slight rebound and eventual 

stabilization at levels up to 3 pH units lower than pre-CO2 conditions. 

Stabilized pH values varied between 4.3 and 5.8, suggesting that mineral 

assemblages had varying buffering capacities. Reactors containing carbonate 

minerals showed higher pH values in the CO2 run than the others (Reactors A, B, 

F, and I). In Reactor G, pH was below 3.5 and remained relatively constant 

during both Ar and CO2 flushing. 

Seven water samples from each reactor were analyzed for concentrations of SO4, 

Cl, F, Br, NO3, and PO4. Anion concentrations sharply decreased at the start of 

CO2 run owing to the dilution of added fresh water (Fig. 2 [p. 32-33 of pdf]). 

SO4 and Cl concentrations rebounded but did not reach previous levels. F, Br, 

NO3, and PO4 concentrations were further reduced through CO2 flushing. All 

anions exhibited lower concentrations at the end of the experiment relative to 

pre-CO2 concentrations. SO4 and Cl exhibited the highest concentrations and 

remained stable throughout the experiment, except for the sampling intervals 

immediately following initiation of Ar and CO2 flushing. 

4. Discussion 

Concentration increases observed following the introduction of Ar reflects 

water-rock system equilibration. Water-rock systems at the end of Ar flushing 

should provide fair analogs to natural aquifers, assuming that these aquifers do 

not receive extra input (i.e., brine from depth) other than rainwater. Reactor E 

shows high total dissolved solids (TDS)-as much as 8,000 mg/L in the Ar stage. 

Water samples are dominated by Na and Cl (Fig 2e [p. 32 of pdf]), suggesting 

contamination of drilling mud (mainly NaCl) in core materials. 

By flushing CO2 through the experiment system every 20 minutes, water in the 

reactors was assumed to be saturated with CO2 at atmospheric pressure. Initial 

elevated cation concentrations suggest that mineral dissolution was driven by 

CO2 (Fig. 2a-d, f, and i [p. 32 and 33 of pdf), which is consistent with initial 

decreases in pH caused by increased CO2 partial pressure. 

The 4-week experiment documented increase, stabilization, and/or decline of 

concentrations, indicating that cation mobilization occurs and stabilizes within 

a period of days to weeks. It is well known that reaction rates in laboratory 

batch experiments tend to be higher by orders of magnitude than those in field 

210
conditions. But unlike many previous mixed batch experiments using graded and 

often pure minerals, our use of natural rock samples may help represent more 

realistic reaction timescales. 

4.1. Type I cations 

Among Type I cations, Ca, Mg, Mn, Ba, and Sr experienced the largest increase 

following introduction of CO2 (Fig. 2a-d, f [p. 32 of pdf]), whereas K, Si, and 

B showed smaller increases. Cation release rates in the CO2 run were calculated 

by dividing concentration difference by the time lapse between the two samples. 

Highest release rates occurred at the beginning of each experiment stage and 

declined with time. 

Linear correlations occurred between pH and release rates of cations, such as 

Ca, Mg, Mn, Ba, and Sr (Figs. 4-6 [p. 35-37 of pdf]), which decreased linearly 

as pH increased. Reactors A-D displayed particularly good correlations (Figs. 4 

and 5). In Reactor A, for example, rates of change in Ca and Mg decreased from 

49 and 42 μmol/L/h to near zero, whereas pH increased from 4.8 to 5.5 in the CO2 

stage (Fig. 4). Both concentrations increased by a factor of 12 during the CO2 

run. Total increase in concentration was 2.9 mol/L for Ca and 2.8 mol/L for Mg. 

Correlation coefficients (R2) between Ca, Mg, Mn, Sr, and Ba concentrations were 

all above 0.98, indicating a strong correlation. Reactor B also showed similar 

results. Dissolution of dolomite was likely the source of these cations because 

molar concentrations of Ca and Mg in dolomite are approximately equal. Dolomite 

also contains trace elements of Mn, Sr, and Ba, which substitute for Mg and Ca 

(e.g., Veizer 1983; Gillhaus et al. 2000; Carmichael et al. 2008). Good 

correlations between these elements suggest dolomite as the single source from 

which these elements were mobilized. The decrease in cation release rate 

demonstrates that dissolution rate of dolomite is linearly dependent on pH. pHdependent dissolution of carbonate minerals was also discussed in an injection 

study in basaltic rocks by Matter and Takahachi (2007). Laboratory studies using 

mixed-flow (e.g., Pokrovsky et al. 2004) and flow-through (e.g. Duckworth and 

Martin 2004) methods also reveal pH dependence on carbonate dissolution rates. 

In Reactors C and D, Ca and Mg release rates also decreased linearly as pH 

increased, indicating dolomite as the primary source. But the release rates of 

Ca were slightly higher than Mg (Fig. 5 for Reactor C [p. 36 of pdf]). Overall 

increases of Ca and Mg amounted to 240 and 180 .mol/L in Reactor C, 220 and 170 

.mol/L in Reactor D. Ca:Mg ratio of this dolomite is about 1.3:1. 

Reactor F, which contains the Ogallala aquifer sample, showed larger elevations 

211
of Ca (124×), Mg (107×), Sr (66×), Ba (50×), and Mn (195×) after CO2 was 

introduced (Fig. 2f; Table 2). Unlike the aforementioned samples, release rates 

of Ca (194 μmol/L/h) were 10 times that of Mg (19.6 μmol/L/hr) at low pH at the 

start of the CO2 run (Fig. 6 [p. 37 of pdf]). Overall increase of Ca and Mg by 

CO2 was 6.3 and 1.3 mol/L, respectively. Thus, the sourcing mineral should 

contain Ca as the dominant metal element, which is consistent with XRD data that 

detected the presence of calcite, but not dolomite. Mg was released either from 

calcite, which could contain a certain amount of Mg as a substitute element of 

Ca, or from dolomite, which exists in small abundance below the XRD detection 

limit. The correlations between Ca, Mg release rate and pH are weak compared to 

Reactors A - D (Fig. 6 [p. 37 of pdf]). Correlation coefficient (R2) between Ca 

release rate and pH is 0.62; it is 0.64 between Mg and pH. It suggests multisources for the cations. 

Evidence of carbonate dissolution was observed by SEM for samples in Reactors A 

and B (Fig. 1c-e [p. 29-31 of pdf]). Dolomite grains in original samples of 

Reactors A and B were mostly fresh looking with smooth surface and were free 

from clay coatings (Fig. 1c). They were the latest diagenetic products and did 

not suffer corrosion events. In reacted samples, however, most dolomite crystals 

displayed corroded surfaces and were commonly pitted with holes (Fig. 1d, e). 

This contrast suggests that dolomite dissolution took place during the 

experiment. In the cation profiles, major Ca and Mg releases occurred 

synchronously with the input of CO2, which therefore resulted in a period of 

dolomite dissolution. 

XRD analysis failed to detect the presence of dolomite in samples for Reactors C 

and D. Given the lack of XRD signal, the abundance of dolomite should be below 3 

wt%. However, the presence of this small amount of carbonate enabled the related 

cation concentrations to increase rapidly, more than six fold for related 

cations, implying that CO2 leakage into aquifers would cause significant metal 

mobilization related to carbonate minerals, even if only a small amount of 

carbonate existed in the aquifers. Dissolution of carbonate is likely to be the 

dominant process in fluid-mineral reactions caused by elevated CO2. 

No obvious difference can be seen between the results of Reactors A and B, C and 

D. The heating process for rock material before the experiment apparently did 

not cause large changes in reactions in Reactors B and D, suggesting that 

potential microbial activities had little influence on mineral-water 

interactions. 

K and Si are the other two cations that showed steady increase during CO2 input 

212
(Fig. 2; Table 2 [pp. 32-33 and 26). However, the increase was three times 

smaller than that of Ca and Mg. Final concentrations of K and Si were less than 

10 ppm. The correlation coefficient (R2) between K and Si concentrations 

(ranging from 0.23 in Reactor E to 0.95 in Reactor F) was generally lower than 

those between carbonate-related elements, indicating multiple controlling 

factors. Samples containing K-feldspar (Reactors A-D, F, G, and H) showed larger 

increases in K than samples without it (Reactors E and I) (Table 1; Fig. 2 [pp. 

25, 32-33 of pdf), suggesting that Kfeldspar dissolution is the main source of 

K release (Equation 1). Dissolution of K-feldspar released K and Si at a ratio 

of 1:2. In Reactors A and B, however, the total concentration increase of K and 

Si was about the same (0.13 and 0.13 mol/L in Reactor A; 0.10 and 0.15 mol/L in 

Reactor B). This suggests that quartz precipitated simultaneously and reduced 

the Si content in water. However, quartz precipitation could not be confirmed by 

SEM observation. 

The Reactor E sample has a simple mineral composition of quartz, illite, and 

montmorillonite (smectite) (Table 1 [p. 25 of pdf]). Although TDS quickly 

increased to high levels during the Ar stage (as much as 8,000 mg/L), only Si 

concentrations exhibited a rapid change, increasing from 58.4 to 2,608 .mol/L 

during the CO2 stage (Fig. 2e; Table 2 [p. 32 and 26 of pdf]). These Si 

concentrations suggest that quartz dissolution is the dominant process. Mg shows 

a slight increase from 10.6 to 19.6 mmol/L after introduction of CO2. Smectite 

is unlikely the mineral source because Al and Si would have shown a similar 

scale of increase. Instead, a small amount of Mg-rich carbonate might be the 

source. Both smectite and illite appear inert under high levels of CO2, as 

suggested by the absence of a related cation concentration variation. 

4.2. Type II cations 

Type II cation concentrations first increased then decreased and/or fluctuated 

after CO2 input, suggesting that adsorption/desorption are the important 

processes controlling these constituents. Initial decreases in pH resulted in 

rapid dissolution and/or desorption to release the cations. Subsequent 

concentration decreases may have been the result of adsorption on sorbents such 

as hydrous oxides, organic matter, and clay minerals (Metcalfe 1996). 

Major factors controlling sorption of heavy metals include pH, metal 

concentration, speciation of cations involved, solid:solution mass ratio, and 

contact time (Temminghoff et al. 1997; Martinez and Motto 2000; Bradl 2004). In 

general, decreases in pH encourage desorption and liberate metals to the 

solution (Yin et al. 1996). In the experiment, after CO2 was introduced into the 

213
system, metal concentrations in the waters increased through time, and initial 

decreases in pH caused metal desoprtion. Then adsorption occurred when 

increasing cation concentration and pH reached critical levels. Thus, 

concentrations of Type II started decreasing toward the end of the experiment. 

The controlling effects of pH on desorption/adsorption of Fe and Al are best 

illustrated in Reactor 1 (Fig. 4 [p. 35 of pdf]). Release rates of Fe and Al 

were highest at the start of the CO2 stage when pH was reduced to its lowest 

point. Then release rates decreased and became negative, indicating adsorption 

replacing desorption, when mineral buffering occurred and pH increased slightly. 

As desorption/adsorption processes became balanced, cation release rates reached 

near-zero toward the end of the experiment, indicating that pH and elevated 

metal concentrations were reaching a new equilibrium. Note that 

adsorption/desorption could also have occurred with other heavy metal ions, such 

as Co, Mn, or Zn, but the processes may be masked by more significant effects of 

mineral dissolution. 

Results of this study suggest that adsorption processes could mitigate the 

hazardous effects of metal mobilization. In the event of CO2 leaking into a 

fresh-water aquifer, certain cations such as Fe, Al, Mo, Cr, Cs, and Cu may 

experience a short-term perturbation, but, as this study suggests, eventually 

decrease. In this case, these cations posed limited risks to water quality and 

would not be reliable as an indicator species for monitoring. 

4.4. Anions 

Anion concentrations measured showed no significant increases after introduction 

of CO2 (Fig. 2 [p. 32-33 of pdf]), suggesting that the increase of cation 

concentrations following introduction of CO2 was mainly balanced by an increase 

of HCO3, which would occur with the dissolution of CO2. 

The small rebound in SO4 and Cl at the beginning of the CO2 run represents 

reequilibration between water and minerals after dilution. SO4, Cl, and Na 

failed to recover fully to predilution values. No influence from sulfate 

minerals was detected in the reactors. It was noted that because the samples 

used were from a conventional core collection and exposed to atmosphere for 

years, fine sulfides might have been oxidized and were no longer sensitive to pH 

changes (John Apps, personal communication, 2008). Additional sampling of fresh 

core in the field is planned to assess this case. For groundwater monitoring, 

because high CO2 levels had a depressing effect over Br, F, and PO4, bicarbonate 

would be the most variable anion to signal CO2 leaking into an aquifer. 

214
4.5. Risk to water quality 

Potential risks to drinking water quality are Type I heavy metals such as Mn, 

Ba, Sr, Co, and Zn, which showed increases by as much as two orders of magnitude 

and remained at elevated levels during CO2 input (Fig. 2; Table 2 [pp. 32 and 26 

of pdf]). Among them, Mn, Ba, and Sr reached highest concentrations in Reactors 

A-D, F, and I. In Reactor A, for example, Mn increased rapidly from 14 ppb preCO2 to 2,658 ppb in the last water sample, exceeding the Environmental 

Protection Agency (EPA) maximum contaminant level (MCL) of 50 ppb (Table 2). 

Mobilization of these elements is therefore the main concern for potential 

deterioration of water quality due to CO2 leakage. 

As discussed earlier, carbonate minerals contain trace amounts of Mn, Ba, and Sr 

as substitute divalent cations. These heavy metal elements will be mobilized 

into the water with the dissolution of carbonate minerals driven by pH 

decreases. The amount of release, of course, depends on the quantity of the 

carbonate dissolved and abundances of these elements in the carbonate minerals. 

Experiment results suggest that heavy metals related to carbonate minerals can 

be elevated above ambient as much as hundreds times as a result of excessive CO2 

supply. Therefore, it is important to define distribution and chemical 

composition of carbonates within an aquifer in order to assess risk of hazardous 

metal mobilization. Monitoring programs should focus on elements that exist in 

carbonate minerals. Even minor amounts of carbonate minerals dominate the rockwater reaction. Risk assessment and monitoring strategies ought to therefore be 

based on laboratory rock-water reaction of a representative spectrum of aquifer 

rock samples exposed to CO2, and not solely on petrographic analysis, which may 

miss trace amount of carbonate species. Unperturbed groundwater should, however, 

reliably show equilibration with carbonate species in the aquifer, which will 

reduce uncertainty in assessment. 

4.6. Limits of study 

This laboratory survey study was designed to determine typical types of CO2 

reaction with typical aquifers to aid in designing the next set of field tests. 

Batch reaction does not consider reactive transport issues when reaction 

products continue to flow through the rock-fluid system, thus leading to 

buffering and attenuation away from the point at which CO2 is introduced. Study 

results show that reaction of CO2 with aquifer systems is strongly case 

specific, so results of selected samples should not be generalized widely. In 

fact it would be wise to include a population of samples from within one aquifer 

215
to characterize it adequately. The study was also limited because aquifer 

samples were not collected with corresponding groundwater and were perturbed to 

some extent by drilling fluids and by interaction with the atmosphere. In 

particular, aquifer redox conditions may not have been accurately represented in 

batch-reaction vessels. 

The finding that even trace carbonate minerals control cation and anion 

reactions should, however, be robust, even within these study limits, and it 

provides an important conclusion to proceed with the additional testing planned 

at several field sites using paired fresh (minimally oxidized) core samples and 

associated groundwaters. 

5. Conclusions 

The batch-reaction experiment demonstrated that CO2 influx at room temperature 

and pressure can mobilize significant numbers of cations from a variety of 

aquifer host rocks. Measured cation concentrations in the CO2 phase of the 

experiment are strongly aquifer-specific and increased as much as two orders of 

magnitude from those during the preceding Ar gas run. Rapid cation mobilization 

occurred in a short time span (within the first several hours to 2 days), and 

concentrations stabilized or declined before the end of the CO2 experimental run 

(14 days). 

Two types of cation trends were recognized (Table 2 [p. 26 of pdf]). Type I 

cations, including Ca, Mg, Si, K, Sr, Mn, Ba, Co, B, and Zn, were permanently 

elevated by CO2 input (Fig. 2; Table 2 [p. 32-33 and 26 of pdf]). Concentrations 

stabilized before the end of the experiment after an initial rapid increase. Ca, 

Mg, Mn, Ba, and Sr concentrations increased after introduction of CO2 by as much 

as two orders of magnitude. Good correlations between Ca and Mg concentrations 

suggest that carbonates are source minerals. High correlations between cation 

release rates and pH suggest that dolomite dissolution is pH dependent. Cation 

release rates gradually decreased with increasing pH, which was related to 

mineral buffering. The experiment suggests that carbonate minerals, which 

commonly exist in aquifer host rocks, pose major potential risks to groundwaterquality degradation, should an error occur and CO2 leak from the storage 

interval into fresh water. 

Type II cations increased rapidly after introduction of CO2, then declined, in 

most cases, to lower than pre-CO2 levels (Fig. 2; Table 2). This category 

includes Fe, Al, Mo, U, V, As, Cr, Cs, Rb, Ni, and Cu. 

216
Concentrations declined as adsorption occurred when mineral buffering took 

effect, causing pH to rebound and increase cation concentrations. This study 

suggests that risks from Type II cations may be limited because of mitigation of 

initial mobilization by adsorption. 

Experiment results provide possible magnitudes and rates at which heavy metal 

elements could be mobilized from aquifer host rocks if they are affected by CO2 

leakage. Our results suggest that dissolution of carbonate minerals, which 

contain trace amounts of Mn, Ba, and Sr, could be the most important threats to 

groundwater quality if CO2 leakage occurs. In addition, carbonate minerals are 

sources of alkalinity, which may increase costs of water treatment for use. 

Surveying distribution and chemical composition of even minor amounts of 

carbonates within fresh-water aquifers in question is therefore crucial so that 

potential perturbation can be determined. Cations in carbonates are the highest 

signal components to be considered in groundwater monitoring for leakage 

assessment. 

This experiment represents a worst-case scenario of excessive amounts of CO2 

leakage to aquifers. In a realistic leakage situation, the ratio between CO2 

supply and water rock would be far smaller. Dissolution of carbonates would most 

likely consume the relatively small amount of leakage and buffer pH. 

Deterioration of water quality due to carbonate dissolution would therefore be 

restricted to within the vicinity of the seeping points. 

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Table list 

Table 1 

Aquifer rock samples used in the experiment and mineral compositions 

Table 2 

Cation concentrations during CO2 and Ar stage for each sample. Cations are 

divided into Type I (stable) and II (unstable), according to their different 

221
concentration profiles. Type I cations rapidly increased in concentration 

following initial introduction of CO2, then increase rates slowed down and 

concentrations stabilized prior to the end of the experiment. Type II cations 

experienced rapid increases in concentration after introduction of CO2, but 

decreased to lower than the pre-CO2 levels at the end of CO2 fluxing. The first 

value of each cell is the final concentration of the Ar phase; the last value is 

the final concentration of the CO2 phase. Middle values in some cells are the 

maximum concentration before decline in the CO2 run. 

Figure list 

Fig. 1a Secondary electron SEM photomicrograph of original sample used in 

Reactor H. Hickory Aquifer, 86.0 m deep, Manson County, Texas. K-feldspar (K-f) 

and quartz (Q) grains are severely corroded 

Fig. 1b Secondary electron SEM photomicrograph of original sample used in 

Reactor H. Hickory Aquifer, 86.0 m deep, Manson county, Texas. Kaolinite (Kao) 

occurs as booklets. A K-feldspar (K-f) grain show corroded surface 

Fig. 1c Secondary electron SEM photomicrograph of original sample used in 

Reactors A and B. Dockum Aquifer, 30.5 m deep, Randall County, Texas. Dolomite 

rhombs (Do) show fresh-looking surface. Smectite (Sm) occurs as mineral coating 

and pore-filling 

Fig. 1d Secondary electron SEM photomicrograph of reacted sample from Reactor A. 

Dockum Aquifer, 30.5 m deep, Randall County, Texas. Dolomite grains (Do) are 

corroded with scattered, patchy clay on surface 

Fig. 1e Secondary electron SEM photomicrograph of reacted sample from Reactor C. 

Cranfield loess, surface sample, Adams County, Mississippi. Dolomite (Do) 

crystal partly corroded. Smectite fragment growing on dolomite surface 

Fig. 2 Water chemistry as a function of time, Reactor A-I. CO2 replaced argon 

gas flow on Day 14, following which most cations show rapid elevation. 70 ml of 

water was added to reactors at start of CO2 run, complicating concentration 

trends 

Fig. 3 pH profiles of Reactors A-I along course of experiment. CO2 replaced 

argon gas flow on Day 14, when pH abruptly dropped as much as 3 units. Then pH 

slightly rebounded as mineral buffering occurred, except in Reactor G 

222
Fig. 4 Cation release rates as a function of pH in CO2 run, Reactor A. Release 

rates of Ca, Mg, Mn, Sr, and Ba linearly declined as pH increased. Ca and Mg 

show equal release rates, indicating dolomite as sourcing mineral. Mn, Sr, and 

Ba are also mobilized from dolomites in which they exist as substitute elements 

for Ca and Mg. Dolomite dissolution rate linearly depends on pH. Release rates 

of Al and Fe had become negative toward the end, suggesting that adsorption had 

occurred 

Fig. 5 Cation release rates as a function of pH in the CO2 run, Reactor C. 

Excellent correlation between cations suggests single sourcing mineral: 

dolomite. Cation release rates declined linearly as pH increased, suggesting 

that dissolution rate is linearly dependent on pH 

Fig. 6 Cation release rates as a function of pH in the CO2 run, Reactor F. 

Release rates of Ca are much higher than Mg, suggesting that calcite dissolution 

as the cation source. Release rates had dropped to near zero and dissolution had 

stopped by the end of the experiment 

[Table 1] - refer to EPA-HQ-OW-2008-0390-0387.pdf 

[Table 2] - refer to EPA-HQ-OW-2008-0390-0387.pdf 

High Resolution Images of Figure 1a through Figure 6 available in EPA-HQOW-2008-0390-0387.pdf 

Figure 1a - page 27 of pdf 

Figure 1b - page 28 of pdf 

Figure 1c - page 29 of pdf 

Figure 1d - page 30 of pdf 

Figure 1e - page 31 of pdf 

Figure 2 - page 32-33 of pdf 

Figure 3 - page 34 of pdf 

223
Figure 4 - page 35 of pdf 

Figure 5 - page 36 of pdf 

Figure 6 - page 37 of pdf 

To download Supplementary Material: Table S1.xls refer to page 38 of pdf. 

Individual Response: EPA has reviewed the paper, “Potential risks to fresh-water resources as a 

result of leakage from CO2 geological storage-a batch-reaction experiment.” EPA acknowledges the 

submittal and will continue to review studies and field results related to the movement of trace 

elements in ground water and the potential for CO2 influx to mobilize cations from a variety of aquifer 

host rocks. EPA intends to continue to collect data on GS and to incorporate such data and information 

as it implements its adaptive approach to the GS rulemaking to incorporate new research, data, and 

information about GS. For more information on the adaptive approach, see the responses to 

comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28320 

Comment: Since I spoke at last year's public hearing, there have been several papers that 

demonstrated this excellent record of producing, transporting and injecting CO2. 

The first study by Duncan et al examines the safety risks associated with large 

scale CO2 sequestration by taking a systematic review of all accident and 

blowout data associated with CO2 pipeline, transport and injection. It finds 

that, "the CO2 EOR industry has an excellent safety record," and, "the rarity of 

corrosion related incidents reflects the industry's success in implementing 

anti-corrosion measures." 

The second study by Smith et al demonstrates the industry's protection of the 

environment, examines the groundwater in the SACROC CO2 EOR field, and finds 

that, "no widespread degradation of water quality exists inside the SACROC 

224
oilfield as a result of CO2 injection." A third study on the mechanical 

integrity of CO2 injection wells is in progress and should be completed by the 

filing deadline. 

Individual Response: EPA has reviewed the papers referenced by the commenter. EPA 

acknowledges the submittals and will continue to review studies related to evaluation of actual field 

results and CO2 effects on ground water. EPA adds that is has been monitoring the progress at 

SACROC. EPA intends to continue to collect data on GS and to incorporate such data and information 

as it implements its adaptive approach to the GS rulemaking to incorporate new research, data, and 

information about GS. For more information on the adaptive approach, see the responses to 

comments on the proposed rule in the rulemaking docket.

EPA adds that CO2 transport is out of the scope of the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 22-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3000 3. Injection Depth for GS Projects 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28196 

Comment: 13. We strongly concur with the observation that "treating high-salinity" waters 

(i.e. those in excess of USDW protectiveness threshold) will be generally less 

225
costly than obtaining water rights. 

Individual Response: EPA acknowledges the concerns regarding water availability and interest in 

current and future water resources and recognizes that advances in technology are making high TDS 

aquifers more attractive as potential future water sources. EPA clarifies that the primary purpose of 

the GS rule is the protection of USDWs from endangerment and the purpose of the permitting, siting, 

construction, operation, monitoring, post-injection site care, financial responsibility, and site closure 

requirements for Class VI injection wells is to further this goal. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27973 

Comment: Comment No. 30 

Page 44809 

Issue Topic from EPA's NODA 

Water availability research in the United States indicates that water treatment 

of higher salinity waters (in excess of the USDW protectiveness threshold of 

10,000 ppm TDS) may be more cost effective than the cost of obtaining water 

rights or surface water elsewhere in the area (Sengebush, 2008). 

Carbon Sequestration Council Comments 

There is a growing recognition that CCS may be treated as a public necessity, 

and future long term planning should include provision for CO2 storage as well 

as water supply. The appropriate authorities will need to work together to 

reconcile such plans to assure that resources are effectively deployed. 

Responsibility for this activity falls outside that of individual CCS project 

developers. 

226
Individual Response: EPA agrees that CCS is an important climate change mitigation tool; however 

the primary goal of the GS rule is the protection of USDWs. EPA believes that the waiver process at 

§146.95 provides flexibility to address storage capacity concerns while assuring that appropriate 

requirements are in place to protect USDWs from endangerment. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28128 

Comment: As originally proposed, the Class VI provisions would have prohibited any 

injection and storage in receiving formations above the lowermost USDW.[Footnote 

2] 

[Footnote 2] Several commenters wrote in favor of the blanket prohibition, and 

while EEI does not specifically address each of their comments here, two 

comments in particular warrant mention. The first stated that injection below 

the lowermost USDW is a long-standing principle of UIC deep well injection. 

This is of course true with regard to Class I wells, which include wells used to 

inject hazardous industrial wastes (not CO2). However, injection above the 

lowermost USDW is also a widespread practice with regard to Class II wells, 

including those specifically designed to inject CO2 for purposes of enhanced oil 

recovery. Each injection well permitted under the UIC program is required to 

demonstrate that USDWs will not be endangered. Injection limitations for CO2 

are not mandated simply because hazardous wastes are subject to such 

limitations. EEI’s previous comments contain further discussion regarding why 

it is not appropriate to subject CO2 injection wells to regulation designed to 

address hazardous wastes. 

The second comment stated that given the relatively untested nature of 

commercial-scale GS, injection limitations are prudent during the early years 

and may be relaxed later should experience warrant. While EEI does not disagree 

that GS rules may be tailored appropriately as expertise is gained through 

experience, imposing injection depth limitations across the board is unnecessary 

(in addition to the reasons explained below) given the incentives that are 

227
likely to drive early CCS projects. For example, the initial commercial-scale 

CCS projects may likely be those that offer the very best in terms of siting 

characteristics. 

Individual Response: EPA agrees that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes this approach: 1) responds to concerns 

about local and regional geologic storage capacity limitations imposed by the proposed injection depth 

requirements; 2) allows for a more site-specific assessment of injection depth for GS projects; 3) 

accommodates injection into different formation types; 4) allows for injection of CO2 for GS into nonUSDWs above and/or between USDWs when appropriate and where it can be demonstrated that 

USDWs will be protected; and 5) responds to concerns about the use of aquifer exemptions for GS. 

Finally, EPA's approach to addressing injection depth variability through a waiver process responds to 

concerns about future drinking water resource availability and the need to ensure that high quality 

water remains available in sufficient quantities to supply drinking water needs. 

EPA believes that through the waiver process, the GS rule avoids a "blanket prohibition" of injection 

into any formation types, so long as the injection is demonstrated to be protective of USDWs. The final 

GS rule maintains the principles of site-suitability and flexibility and does not categorically preclude or 

prohibit injection into any type of formation. Instead, the requirements are designed to ensure 

protection of USDWs through proper siting, well construction, operation, monitoring, and postinjection site care at all sites selected for GS. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3100 3.1. Comments on Concerns About Injection Depth for Class VI Wells 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

228
Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28198 

Comment: 15. We strongly support the EPA view that different well classes warrant 

different treatment, and that EPA approval criteria should therefore differ. CO2 

at injection pressures will greatly differ from other fluids regardless of well 

class. In EPA’s phrase, "site-suitability" for GS is what needs to be 

determined. 

Individual Response: EPA agrees that site and project specific factors are important in determining 

the applicability of GS in a specific formation. The final GS rule includes flexibility for the Director to 

consider site-specific geology and proposed operational conditions when making permitting decisions. 

EPA believes that proper siting, well construction, operation, monitoring, and post-injection site care 

are key to determining site suitability for GS and ensuring USDW protection from endangerment. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

EPA Letter ID: 0339 

EPA Comment ID: 28010 

Other EPA Comment Codes and Descriptions: 3220 3.2.2. Comments in Opposition to the 

Approach 

Comment: B. SWRCB Comment #2 on: "IV. Injection Depth for GS Projects A. What did EPA 

propose for Class VI well injection depth relative to the location of USDWs?" 

Injecting CO2 above or below the water supply aquifer is irrelevant since under 

extreme pressure and high temperature, CO2 gas will migrate downward and upward, 

following porosity, fault zones or man-made pathways. Plus, you cannot compare 

CO2 gas to liquid injection since CO2 gas will expand under pressure in all 

directions, and has much greater mobility than fluids. Gas will penetrate rock 

with much smaller opening pores or fractures than those needed for fluid 

229
migration. Fluid compressibility and subsequent expansibility is negligible 

compared to this of gases. The LBNL modeling showed injected gas will expand for 

hundreds of miles, for many years after injection stops, and sooner or later may 

reach area(s) where will be able to escape to the surface or drinking water 

aquifer. 

CO2 is heavier than air and if release to the surface at high concentration will 

be deadly. 

Individual Response: EPA believes proper siting, well construction, operation, monitoring, and postinjection site care will allow CO2 to be sequestered, despite its buoyancy. The GS rule is designed to 

ensure that appropriate requirements are in place to protect USDWs from endangerment. EPA 

acknowledges that faults and artificial penetrations offer paths for fluid movement. For this reason, 

the GS rule contains requirements at §146.82 for characterization of faults and fractures, and §146.84 

requires an AoR evaluation and corrective action. For additional information on characterization of 

faults and fractures, AoR, and corrective actions, see the preamble to the final rule and the responses 

to comments on the proposed GS rule. 

In addition, owners or operators seeking waivers from the injection depth requirements must provide 

additional information about the injection zone; identification of confining units above and below the 

injection zone; and tailored AoR modeling above and below the injection zone, as required at 

§146.95(a). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27869 

Comment: The critical component to confining any injection stream is suitable top and 

bottom confining zones, regardless of the location of a USDW. NODA page 44809 

states, "placing distance between the injection formation and USDWs decreases 

risks to USDWs". Distance may help but is not the definitive factor. It will 

not compensate for poor site characteristics. Neither does lack of distance 

defeat a site that is properly designed and sited. The ability of the confining 

230
zones to sequester the injection stream must be taken into account, along with 

distance, in determining whether the site is suitable. Site selection must 

focus on the trapping and confinement characteristics without giving undue 

deference to distance. 

Individual Response: EPA agrees that suitable confining layers (e.g., low-permeability, low-porosity 

formations identified through proper site characterization process) along with proper well construction, 

operation, monitoring, and post-injection site care are key to protecting USDWs from endangerment.

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

Owners and operators seeking waivers must provide a supplemental report (the GS Class VI injection 

depth waiver application report) referenced at §146.82(d) and outlined at §146.95(a) with additional, 

site-specific information including: additional information about the injection zone; identification of 

confining units above and below the injection zone; tailored AoR modeling above and below the 

injection zone; a demonstration that well design is appropriate and protective of USDWs, in lieu of 

specific requirements at §146.86; a description of how monitoring will be tailored for injection 

above/between USDWs; and information about public water supplies in the AoR. 

EPA Team Member:

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28048 

Comment: Finally, the assertion that "...placing distance between the injection formation 

and USDWs decreases risks to USDWs" (NODA p. 44809) is an overly general 

statement that should not influence regulation. Injection depth requirements 

would not accomplish the goal of protecting USDWs because the true issue is the 

quality of the sealing formation(s) and the presence or absence of other likely 

leakage pathways. A good quality top seal is demonstrated by permeability, 

porosity, mineralogy, and other physical properties rather than thickness or 

231
distance from USDWs. 

Individual Response: EPA agrees that suitable confining layers (e.g., low-permeability, low-porosity 

formations identified through proper site characterization process) along with proper well construction, 

operation, monitoring, and post-injection site care are key to protecting USDWs from endangerment. 

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

Owners and operators seeking waivers must provide a supplemental report (the GS Class VI injection 

depth waiver application report) referenced at §146.82(d) and outlined at §146.95(a) with additional, 

site-specific information including: additional information about the injection zone; identification of 

confining units above and below the injection zone; tailored AoR modeling above and below the 

injection zone; a demonstration that well design is appropriate and protective of USDWs, in lieu of 

specific requirements at §146.86; a description of how monitoring will be tailored for injection 

above/between USDWs; and information about public water supplies in the AoR. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28261 

Comment: Further, a blanket exclusion will hinder the ability of existing and possibly 

future Class I, II, and V projects to convert to Class VI projects. The proposed 

"grandfathering" provision for existing wells, as currently drafted, is limited 

to well construction and does not include any provision for projects to be 

grandfathered in to new siting provisions for Class VI wells. Thus, the 

regulations would exclude from the scope of potential grandfathering all 

projects that do not inject below the lowermost USDW. Such projects would have 

no ability to convert to Class VI GS projects. NACCSA believes that, in 

particular, EOR operations using CO2 should be allowed to transition to 

dedicated storage-only operations, if desired, where certain requirements are 

met. Regulations that essentially prevent them from doing so where injection has 

232
occurred above the lowermost USDW would greatly disincentivize many projects 

that would otherwise be likely to go forward and hamper commercialization of 

CCS. And creation of such a disincentive is unnecessary because the wells at 

issue would have been designed and constructed specifically with injection of 

CO2 and the protection of USDW in mind. 

Finally, a complete ban on injections to only those formations below the 

lowermost USDW- currently in place only for Class I hazardous waste injection 

wells-is likely to create a public misimpression that CO2 injection wells are 

analogous to hazardous waste injection wells and carry analogous risks. 

Individual Response: EPA agrees that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes this approach: 1) responds to concerns 

about local and regional geologic storage capacity limitations imposed by the proposed injection depth 

requirements; 2) allows for a more site-specific assessment of injection depth for GS projects; 3) 

accommodates injection into different formation types; 4) allows for injection of CO2 for GS into nonUSDWs above and/or between USDWs when appropriate and where it can be demonstrated that 

USDWs will be protected; and 5) responds to concerns about the use of aquifer exemptions for GS. 

Finally, EPA's approach to addressing injection depth variability through a waiver process responds to 

concerns about future drinking water resource availability and the need to ensure that high quality 

water remains available in sufficient quantities to supply drinking water needs. For additional 

information on grandfathering of Class I and Class II wells, see the preamble to the final rule and the 

responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 28563 

Comment: - There is an unknown level of risk associated with large geologic sequestration 

projects. Regulations must set high standards for site selection, site 

characterization and ongoing monitoring. 

233
- The proposed rules and new data also do not adequately address other types of 

hazards, such as those associated with hydro fracing and impacts to existing 

faults. 

Individual Response: EPA agrees that site selection, site characterization, and monitoring, along 

with well construction, operation, and post-injection site care are important to protect USDWs from 

endangerment. EPA believes the final GS rule sets high standards for USDW protection that are 

tailored to the unique challenges posed by GS.

For additional information on proper site characterization, pressure limits, and the use of hydraulic 

fracturing at GS projects, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Stan Belieu 

Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC) 

EPA Letter ID: 0378 

EPA Comment ID: 28569 

Comment: Based on our experience we disagree with the NODA on "placing distance between 

the injection formation and USDWs decreases risks to USDWs. Distance may help 

but is not the definitive factor. It will not compensate for poor site 

characteristics. Neither does lack of distance defeat a site that is properly 

designed and sited. The ability of the confining zones to sequester the 

injection stream must be taken into account, along with distance, in determining 

whether the site is suitable. Site selection must focus on the trapping and 

confinement characteristics without giving undue deference to distance. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

234
Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

However, EPA acknowledges that there are situations where injection into non-USDW formations 

above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28571 

Comment: The EPA’s stated basis for requiring sequestration above a USDW, that "placing 

distance between the injection formation and USDWs decreases risks to USDWs" 

(NODA p.44809) is too simplistic. Distance will undoubtedly help, but distance 

does not deserve to be singled out like this; it will not make up for otherwise 

poor site characteristics nor does the lack of depth defeat a good site. The 

nature and characteristics of the confining material is paramount and must be 

considered along with distance in determining the sufficiency of containment at 

any particular site. Site selection and characterization must focus on the 

trapping and containment mechanisms themselves without giving undue weight to 

distance, which plays a role but is not always determinative. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

235
However, EPA acknowledges that there are situations where injection into non-USDW formations 

above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27969 

Comment: Issue Topic from EPA's NODA 

The basis of these requirements is the principle that placing distance between 

the injection formation and USDWs decreases risks to USDWs. 

Carbon Sequestration Council Comments 

This is too simplistic; distance will undoubtedly help, but distance does not 

deserve to be singled out like this. The nature and characteristics of the 

confining material is paramount and must be considered along with distance in 

determining the sufficiency of containment at any particular site. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

However, EPA acknowledges that there are situations where injection into non-USDW formations 

above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

236
owners and operators can seek a waiver of the Class VI injection depth requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27970 

Comment: Comment No. 27 

Page 44809 

Issue Topic from EPA's NODA 

In these deep-well injection scenarios, the added depth and distance between the 

injection zone and overlying formations serve both as a buffer allowing for 

pressure dissipation and as a zone for monitoring that may detect any excursions 

(of the injectate) out of the injection zone. 

Carbon Sequestration Council Comments 

Again, this assertion goes too far. Distance is not the only way to accomplish 

these objectives and will not make up for otherwise poor site characteristics. 

Nor does the lack of depth defeat a good site with sufficient containment. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

mitigation, and remediation if conditions warrant. 

However, EPA acknowledges that there are situations where injection into non-USDW formations 

237
above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. For additional 

information on site selection for GS projects, see the preamble to the final rule and the responses to 

comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27971 

Comment: Comment No. 28 

Page 44809 

Issue Topic from EPA's NODA 

Additional distance also allows trapping mechanisms, including dissolution of 

CO2 in native fluids and mineralization, to occur over time - thereby reducing 

risks that CO2 may migrate from the injection zone and endanger USDWs. 

Carbon Sequestration Council Comments 

Site selection and characterization must focus on the trapping and containment 

mechanisms themselves without giving undue weigh to distance, which plays a role 

but is not always determinative. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

Additionally, the Agency believes that distance between the injection zone and USDWs can impede 

vertical fluid movement, allow for pressure dissipation, and provide additional sites for monitoring, 

238
mitigation, and remediation if conditions warrant. 

However, EPA acknowledges that there are situations where injection into non-USDW formations 

above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. 

For additional information on site selection for GS projects, see the preamble to the final rule and the 

responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27972 

Comment: Comment No. 29 

Page 44809 

Issue Topic from EPA's NODA 

Additionally, the depth and distance below the lowermost USDW allow the 

potential for the presence of additional confining layers (between the injection 

zone and overlying formations/USDWs). 

If demonstrated containment is sufficient to meet the siting requirements, then 

additional confining layers are unnecessary. 

Individual Response: EPA believes that suitable confining layers (e.g., low-permeability, lowporosity formations identified through proper site characterization process) along with proper well 

construction, operation, monitoring, and post-injection site care are key to protecting USDWs from 

endangerment. 

However, EPA acknowledges that there are situations where injection into non-USDW formations 

239
above the lowermost USDW can be performed in a manner that protects USDWs, as long as 

appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. For additional 

information on confining zones for GS projects, see the preamble to the final rule and the responses to 

comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3110 3.1.1. National Storage Capacity 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28205 

Comment: Affording all states the opportunity to deploy CCS should not be the motivation 

for allowing or disallowing CO2 injection above a USDW in the final rule. In 

"Section II. What Did EPA Propose?" as well as in other parts of the NODA, the 

USEPA notes that "a few States" were concerned that an outright ban on injecting 

anthropogenic CO2 above a USDW may constrain the deployment of carbon dioxide 

capture and storage (CCS) technologies within those states. While the USEPA 

might well have a statutory responsibility to examine impacts of the proposed 

rule on a state-by-state basis, the ability to deploy CCS in every state is not 

a precondition for CCS being an important aspect of the nation’s portfolio of 

options to address climate change. It is already clear from our published 

research {FOOTNOTE 2} as well as research from other groups {FOOTNOTE 3} that 

CCS is unlikely to deploy in some states for a variety of reasons, including a 

240
fundamental lack of suitable deep storage formations or the presence of more 

cost effective emissions abatement options. In those cases, it is well accepted 

that the impacted states would be able to draw upon other aspects of the 

nation’s greenhouse gas emissions mitigation portfolio to reduce their emissions 

(e.g., renewable energy, nuclear power). While the proposed rule never 

explicitly frames the question of whether to allow CO2 to be stored above a USDW 

in terms of ensuring that all states have the same set of greenhouse gas 

missions mitigation options (which would be impossible given the heterogeneous 

distribution of deep geologic CO2 storage resources), it appears that some of 

the commenters on the July 2008 rule framed their comments and concerns in that 

manner. The USEPA’s focus should be on fulfilling its existing responsibilities 

under the SDWA as well as any future responsibilities related to reducing 

greenhouse gas emissions in the most effective and efficient manner possible for 

the nation. 

{FOOTNOTE 2} For example, it is clear that the adoption of CCS technologies 

across the U.S. will be quite heterogeneous because of differing endowments of 

geologic storage reservoirs as well as the relative cost effectiveness of other 

ways of reducing greenhouse gases will vary across the nation. See for example, 

Wise MA, JJ Dooley, RT Dahowski, and CL Davidson (2007). "Modeling the impacts 

of climate policy on the deployment of carbon dioxide capture and geologic 

storage across electric power regions in the United States." International 

Journal of Greenhouse Gas Control. Volume 1, Issue 2, April 2007, Pages 261-270. 

doi:10.1016/S1750-5836(07)00017-5 

{FOOTNOTE 3} For example, the NATCARB.org database lists the geologic storage 

potential for a number of states as being essentially zero. 

Individual Response: EPA agrees that protection of USDWs is the most important element of 

determining suitability of a site for GS. However, EPA believes that there are situations where injection 

into non-USDW formations above the lowermost USDW can be performed in a manner that protects 

USDWs, as long as appropriate protections are in place. The final GS rule at §146.95 establishes a 

process by which owners and operators can seek a waiver of the Class VI injection depth 

requirements. The purpose of the injection depth waiver requirements is to ensure protection of 

USDWs while allowing the use of GS capacity above and between USDWs if a site is suitable and all 

Class VI requirements are met. 

Because USDW protection is the priority of the GS rule, owners or operators seeking waivers must 

provide a supplemental report (the GS Class VI injection depth waiver application report) referenced 

at §146.82(d) and outlined at §146.95(a) with additional, site-specific information including: 

241
additional information about the injection zone; identification of confining units above and below the 

injection zone; tailored AoR modeling above and below the injection zone; a demonstration that well 

design is appropriate and protective of USDWs, in lieu of specific requirements at §146.86; a 

description of how monitoring will be tailored for injection above/between USDWs; and information 

about public water supplies in the AoR. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28155 

Comment: Additionally, GS opportunities in Wyoming are significantly reduced if the 

waiver process cannot be applied to 'exempted' aquifers above and between USDWs. 

Our experience with Class I wells has shown that significant injection rates and 

volumes most often occur within aquifers which have been 'exempted' in 

accordance with the exemption criteria contained within 40 CFR §146.4. 

I must stress that, in order for GS to be meaningfully successful and 

significant in Wyoming, we must have the ability to sequester CO2 in aquifers 

(above or between USDWs) that can either be 'waived' for the purposes of GS 

solely by the state, or at the least be 'waived' by the state in accordance with 

the process outlined in the NODA and exempted as USDWs in accordance with the 

exemption options contained within 40 CFR §146.4. Our preference is that the no 

aquifer 'exemption' is required for aquifers when an application for waiver has 

been accepted by the state. If an exemption is required, we recommend that it 

not constitute a substantial program revision, and that the determination of 

exemption status be made by the Regional US EPA office. 

Individual Response: EPA agrees that that there are situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs, as long 

as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. The purpose of 

the injection depth waiver requirements is to ensure protection of USDWs while allowing the use of GS 

capacity above and between USDWs if a site is suitable and all Class VI requirements are met. 

242
Because USDW protection is the priority of the GS rule, owners or operators seeking waivers must

provide a supplemental report (the GS Class VI injection depth waiver application report) referenced 

at §146.82(d) and outlined at §146.95(a) with additional, site-specific information including: 

additional information about the injection zone; identification of confining units above and below the 

injection zone; tailored AoR modeling above and below the injection zone; a demonstration that well 

design is appropriate and protective of USDWs, in lieu of specific requirements at §146.86; a 

description of how monitoring will be tailored for injection above/between USDWs; and information 

about public water supplies in the AoR.

EPA believes that there are limited circumstances where aquifer exemptions for GS may be warranted. 

The final rule allows for the expansion of the areal extent of existing aquifer exemptions for Class II 

EOR/EGR wells transitioning to Class VI injection for GS pursuant to requirements at §§146.4 and 

144.7(d). Class VI owners or operators granted expansions of existing Class II EOR/EGR aquifer 

exemptions for GS projects must meet all of the tailored requirements for GS wells in the final GS 

rule. However, the final rule precludes the issuance of new aquifer exemptions for Class VI GS wells; 

that is, aquifer exemptions will only be granted for projects that are transitioning from Class II 

EOR/EGR wells to Class VI. 

The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances. 

The GS rule requires that all aquifer exemption expansion requests be treated as substantial program 

revisions under §145.32 and will require revision of Part 147. Furthermore, if EPA directly implements 

the UIC program in a State, an aquifer exemption expansion requires a revision to the UIC program of 

the applicable State under Part 147. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3120 3.1.2. Allowing GS in All Formation Types 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

243
Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28231 

Comment: EPA should leave the door open for a range of injection sites and methods (some 

of which are not yet fully understood), provided that the CCS project owner or 

operator can show that the injection and storage will be protective of drinking 

water supplies. 

Individual Response: EPA agrees that there are situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs, as long 

as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. The purpose of 

the injection depth waiver requirements is to ensure protection of USDWs while allowing the use of GS 

capacity above and between USDWs if a site is suitable and all Class VI requirements are met. 

Because USDW protection is the priority of the GS rule, owners or operators seeking waivers must 

provide a supplemental report (the GS Class VI injection depth waiver application report) referenced 

at §146.82(d) and outlined at §146.95(a) with additional, site-specific information including: 

additional information about the injection zone; identification of confining units above and below the 

injection zone; tailored AoR modeling above and below the injection zone; a demonstration that well 

design is appropriate and protective of USDWs, in lieu of specific requirements at §146.86; a 

description of how monitoring will be tailored for injection above/between USDWs; and information 

about public water supplies in the AoR. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

244
Commenter Name: B. Peter McGrail 

Commenter Organization: Pacific Northwest National Laboratory 

EPA Letter ID: 0375 

EPA Comment ID: 28162 

Comment: Mischaracterization of Basalts and Coal Seams 

The EPA NODA on pg. 44808 and 44809 refers to basalts and coal seams as examples 

of "shallow" formations impacted by the proposed depth requirement in the draft 

regulations. While shallow basalts and coal seams certainly exist, so do shallow 

saline aquifers as well (i.e. the Coconino aquifer in Arizona). None of these 

shallow formations would be suitable sequestration targets. In contrast, deep 

basalt (and coal seams) exist that appear to offer suitable if not significantly 

lower long-term risk (due to rapid mineralization and other permanent 

sequestration mechanisms) than exist in other reservoirs. Moreover, a cursory 

look at the literature would quickly show that in the Pacific Northwest for 

example, flood basalt formations extend in the deepest parts of the region up to 

16,000 ft bgs. Hence, characterization of these formations as "shallow" is 

demonstrably false, and misleading to the public. 

Individual Response: EPA recognizes that aquifers, coal seams, and basalts can be found both at 

shallow and deep depths. EPA believes that, in some cases these formations can be used for GS, and 

the waiver process in the final GS rule at §146.95 provides additional capacity where these types of 

formations are shallow and protection of USDWs can be demonstrated. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28177 

Comment: In addition, however, given the relative similarity between GS in saline 

formations and oil/gas reservoirs in comparison to GS in coal seams, basalts, 

salt caverns and shales, we are puzzled by the Agency’s omission in including a 

similar comparison of risk profiles between saline and basalts, coal seams, salt 

245
caverns and shales. We therefore reiterate our points above regarding GS in such 

formations. 

Individual Response: EPA recognizes that some types of formations, such as coal seams and 

basalts, are typically shallow and above the lowermost USDW. The Agency expects that injection for 

GS into these shallow formations can be issued waivers and permitted as Class VI wells, provided their 

owners or operators can meet all of the requirements at §146.95 and demonstrate that such injection 

can be performed in a manner that protects USDWs. 

EPA believes that if site characterization is properly conducted, confinement is demonstrated, and 

wells are properly constructed, operated, monitored, and closed then formations such as coal seams 

and basalts can be safely used for GS. The final GS rule does not categorically preclude or prohibit 

injection into any type of formation. EPA believes that the requirements that allow owners or 

operators to seek waivers from the injection depth requirements at §146.95, along with proper siting, 

well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure USDW protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3130 3.1.3. Addressing the Differences Between Class II and Class VI Wells 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28224 

246
Comment: -Drawing a Clear Distinction Between Class II and Class VI Activities: We are 

also pleased that the Agency has drawn a clear distinction between GS injections 

to be covered by this new Class VI category and activities covered by the 

existing Class II category. We believe EPA’s clarification is critically 

important to avoid confusion and/or impediments to existing CO2 uses, such as 

enhanced oil recovery (EOR), already covered under Class II of the UIC regime. 

Individual Response: EPA believes that the tailored requirements for Class VI wells address the 

unique characteristics of CO2 injection for GS. For additional information on the distinctions between 

Class II and Class VI well activities, see the preamble to the final rule and the responses to comments 

on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28262 

Comment: The Agency noted in the NODA several specific comments made in favor of an 

outright prohibition on injection above the lowermost USDW. One comment in 

particular stated that injection below the lowermost USDW is a long-standing 

principle of UIC deep well injection and that, as a result, injection under the 

proposed Class VI regulations should be so limited. This comment fails to take 

into account the decades of experience with injection above the lowermost USDW 

in the context of Class II wells which have been specifically designed to inject 

CO2 for purposes of enhanced oil recovery. Further, as explained in NACCSA's 

prior comments, CO2 injection and storage projects are not analogous to the 

injection of hazardous wastes. Injection limitations that may be appropriate for 

such substances do not necessarily translate (if at all) to the GS context. A 

second comment noted that given the relatively untested nature of commercialscale GS, injection limitations are prudent during the early years and may be 

relaxed later should experience warrant. While NACCSA does not disagree that GS 

rules may appropriately be tailored as expertise is gained through experience, 

imposing injection depth limitations across the board is unnecessary and 

counterproductive, particularly when the EOR context is considered. EOR projects 

247
are likely to be among the "first movers" of CCS projects, and also perhaps the 

projects most likely to be sited above the lowermost USDW. Essentially 

eliminating them by virtue of blanket prohibitions on receiving formations will 

prevent the Agency and the CCS industry as a whole from taking advantage of the 

experience and knowledge they will provide. 

Individual Response: EPA agrees that there are situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs, as long 

as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. The purpose of 

the injection depth waiver requirements is to ensure protection of USDWs while allowing the use of GS 

capacity above and between USDWs if a site is suitable and all Class VI requirements are met. 

The Agency believes the waiver approach accommodates injection into different formation types, 

including depleting oil and gas fields where injection is above the lowermost USDW, and considers the 

concept that CO2 injection for GS above and/or between USDWs could be as safe and effective as 

injection below the lowermost USDW as evidenced by past experiences with Class II wells.

EPA acknowledges that Class II well operators have decades of experience injecting CO2. However, 

EPA believes that significant operational differences between Class II wells and Class VI wells to 

warrant tailored requirements for GS. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28265 

Comment: One topic the NODA does not discuss is how the waiver concept might apply to 

existing (or future) projects permitted outside of Class VI, in particular Class 

II CO2-EOR projects, with injection above the lowermost USDW. As noted above, as 

originally proposed, the coupling of a ban on injection above the lowermost USDW 

with an extremely narrow provision allowing for "grandfathering" of existing 

wells (including EOR wells) into the Class VI category only insofar as well 

construction requirements are concerned essentially meant that CO2-EOR projects 

248
storing CO2 above the lowermost USDW would have no ability to convert to Class 

VI status if so desired. Obtaining a waiver from the deep injection requirement 

would be absolutely critical for such a project to achieve Class VI status. 

NACCSA submits that a preferred approach would be to provide for "automatic" 

waivers for these projects, unless the project at issue can be shown to pose a 

threat to USDW. Notably, the project would have demonstrated the absence of USDW 

endangerment in the original permitting context. 

Individual Response: EPA disagrees that an "automatic" waiver is appropriate where wells are 

grandfathered. However, EPA agrees that there are situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs, as long 

as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. The purpose of 

the injection depth waiver requirements is to ensure protection of USDWs while allowing the use of GS 

capacity above and between USDWs if a site is suitable and all Class VI requirements are met. 

EPA clarifies that owners or operators seeking waivers from the injection depth requirements must 

provide additional information to ensure USDW protection. Specifically, they must submit a 

supplemental report (the GS Class VI injection depth waiver application report) referenced at 

§146.82(d) and outlined at §146.95(a) with additional, site-specific information including: additional 

information about the injection zone; identification of confining units above and below the injection 

zone; tailored AoR modeling above and below the injection zone; a demonstration that well design is 

appropriate and protective of USDWs, in lieu of specific requirements at §146.86; a description of how 

monitoring will be tailored for injection above/between USDWs; and information about public water 

supplies in the AoR.

EPA clarifies that owners or operators of GS/ER projects that were formerly classified as Class II that 

seek to be permitted as Class VI injection wells would also need to demonstrate to the Director that 

the wells were engineered and constructed to achieve the goals of §§146.86(b) and 147.87(a) and 

ensure protection of USDWs. This demonstration would be separate from the waiver application 

process at §146.95. For additional information on grandfathering requirements, see the preamble to 

the final rule and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

249
Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27909 

Comment: Risks 

There are significant risks to GS. We note that GS is not the same as Enhanced 

Oil Recovery (EOR) or Enhanced Gas Recovery (EGR). GS needs to have 

higher standards than EOR activities have had to date for the following reasons: 

- GS is being considered in basins without proven oil and gas capture and 

holding reservoirs. 

- Oil and gas reservoirs are being considered for geologic sequestration even 

where exhausted, and the amount of carbon dioxide to be injected is greater than 

used for EOR/EGR and the goals of the injection are different. 

Individual Response: EPA agrees that ER is different than GS, and clarifies that the final GS rule 

requirements are designed to address these unique attributes of GS. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28176 

Comment: 3. Distinction between Class VI and other wells 

We commend EPA for recognizing that in the NODA that "it is necessary to address 

the specific, unique characteristics of Class VI injection (e.g., large 

injection volumes, viscosity, and buoyancy) and the Agency does not have 

information or data indicating that Class II operations are entirely analogous 

to Class VI, large-scale injection, this alternative allows Class VI injection 

depth considerations to be tailored for GS. A number of dominant differences 

between Class II and Class VI operations indicate that these well classes 

250
warrant different treatment. These differences include: the risk profiles for 

these operations; the greater total injection volumes (of CO2) for Class VI GS; 

and, differences in formation pressures (potentially higher for GS), greater 

opportunities for mobilization of constituents, and injection rates and 

operating conditions." [FOOTNOTE 16] This is of significance as the Agency 

considers how to regulate GS in oil/gas reservoirs. 

FOOTNOTE 16 - 74 Fed.Reg. 44810 

Individual Response: EPA agrees that ER is different than GS, and clarifies that the final GS rule 

requirements are designed to address these unique attributes of GS. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27981 

Other EPA Comment Codes and Descriptions: 2320 2.3.2. Recent Publications on Risk and Risk 

Management 

Comment: Comment No. 38 

Page 44810 

Issue Topic from EPA's NODA 

Third, because the Agency believes that it is necessary to address the specific, 

unique characteristics of Class VI injection (e.g., large injection volumes, 

viscosity, and buoyancy) and the Agency does not have information or data 

indicating that Class II operations are entirely analogous to Class VI, largescale injection, this alternative allows Class VI injection depth considerations 

to be tailored for GS. 

Carbon Sequestration Council Comments 

251
Within the past year, there have been several papers that have demonstrated this 

excellent record of producing, transporting, and injecting CO2. The first study 

by Duncan et al. (2009) examines the safety risks associated with large scale 

CO2 sequestration by taking a systematic review of all accident and blowout data 

associated with CO2 pipeline transport and injection and finds that "The CO2-EOR 

industry has an excellent safety record" and "the rarity of corrosion related 

incidents reflects the industries [sic] success in implementing anti-corrosion 

measures." The second study by Smyth et al. (2009) demonstrates the industry's 

protection of the environment. It examines the groundwater in the SACROC CO2- 

EOR field and finds "that no widespread degradation of water quality exists 

inside the SACROC oilfiled [sic] as a result of CO2-injection." A third study 

on the mechanical integrity of CO2 injection wells is in progress and should be 

completed in time for consideration by EPA. 

[References]: 

Duncan, I., Nicot, J. P., and Choi, J., 2009, Risk assessment for future CO2 

sequestration projects based on CO2 enhanced oil recovery in the U.S., GHGT-9, 

Energy Procedia I, 2037-2042 - presented at the 9th International Conference on 

Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., November 16-20, 

2008. GCCC Digital Publication Series #08-03i. 

Smyth, R.C., Hovarka, S., Lu, J., Romanak, K., Partin, J., Wong, C., and Yang, 

C., 2009, Assessing risk to fresh water resources form long term CO2 injection - 

laboratory and field studies, GHGT-9, Energy Procedia I: 1957-1964 - paper GCCC 

Digital Publication Series #08-03j, presented at the 9th International 

Conference on Greenhouse Gas Control Technologies (GHGT-9), Washington, D.C., 

November 16-20, 2008. Download from BEG/UT website: 

http://www.beg.utexas.edu/gccc/bookshelf/2008/GHGT9/08-03j-Final.pdf. 

Individual Response: EPA acknowledges that several recent and ongoing studies are examining the 

risks associated with CCS, including those studies cited by the commenter, which focus on drawing an 

analogy between ongoing ER projects and CCS. As part of its commitment to an adaptive rulemaking 

approach for wells, EPA is tracking the results of GS-related research and data collected from early GS 

projects. 

EPA agrees with the commenter that industry experience injecting CO2 for the purpose of ER must be 

leveraged in implementation of GS. However, operation of GS sites, while similar to ER in some 

respects, will exhibit the fundamentally different objective of maximizing CO2 injection and 

sequestration. ER projects are operated to minimize CO2 use and maximize oil or gas production. 

252
Therefore, EPA anticipates that the risk posed by GS projects to USDWs will be greater than currently 

operated ER projects and has designed the Class VI GS requirements accordingly. EPA adds that it has 

been monitoring progress at the SACROC site.

As part of its commitment to an adaptive rulemaking approach for wells, EPA will continue to review 

GS-related research such as the forthcoming MIT report and data collected from early GS projects 

such as SACROC. The Agency will evaluate the information and determine whether modifications to 

the requirements are necessary to protect USDWs from endangerment.

EPA has reviewed the cited studies as part of the final rulemaking. EPA notes that although Duncan et 

al. noted that "[t]he CO2-EOR industry has an excellent safety record," their paper is based on case 

studies and does not provide failure rates, so the safety of the industry as a whole cannot be 

quantified. EPA also notes that Smyth et al. indicate that the methods used to detect leaks of CO2 

from ER were not adequate to determine if leaks had occurred. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27982 

Comment: Comment No. 39 

Page 44810 

Issue Topic from EPA's NODA 

A number of dominant differences between Class II and Class VI operations 

indicate that these well classes warrant different treatment. EPA received 

comment during the public comment period supporting the need for such a 

distinction. These differences include: the risk profiles for these operations; 

the greater total injection volumes (of CO2) for Class VI GS; and, differences 

in formation pressures (potentially higher for GS), greater opportunities for 

mobilization of constituents, and injection rates and operating conditions. 

Carbon Sequestration Council Comments 

253
The Multi-Stakeholder discussions (MSD) and recommendations from MSD 

participants have addressed these issues in a series of recommendations that 

account for the different risk profiles. 

The December 23, 2008 letter from MSD participants explained the agreement 

reached on the proposed language describing wells in a proposed new 

classification 40 CFR 146.5(b)(4) that would establish a "bright line" 

definition distinguishing (1) wells that inject CO2 for EOR/EGR and those that 

inject CO2 for GS in conjunction with EOR/EGR from (2) wells that inject CO2 for 

GS where EOR/EGR activities and any hydrocarbon production would be minimal.. 

The signatories to the December 23, 2008, letter recommended, consistent with 

EPA's intent, that wells used for EOR/EGR should remain in Class II and that 

wells used for EOR/EGR with GS - that meet the recommended (b)(4) definition - 

should also remain in Class II and be subject to the current requirements for 

Class II. Signatories to that letter also agreed that the wells used for GS in 

oil and gas reservoirs that do not meet the criteria of (b)(4) should be subject 

to additional requirements. That letter noted an agreement to define such wells 

as wells used "for geologic sequestration in oil and gas formations and where 

the criteria of paragraph (b)(4) are not met." 

In a letter dated October 9, 2009, MSD participants agreed that wells used for 

GS in oil and gas reservoirs that do not meet the criteria of paragraph (b)(4) 

should be subject to a set of additional requirements different from those that 

would apply under the current Class II provisions to wells that inject CO2for 

EOR/EGR and GS, due to the potential change in the risk profile when EOR/EGR 

activities cease. This common view is also reflected in the four letters EPA 

received on March 17, 2009 from MSD participants. Each of those March 17 letters 

asks EPA to include this approach in its final GS rule. Accordingly, EPA should 

adopt the recommended provisions for a new section 146.25 and the 

recommendations submitted with respect to Class V GS wells and Class VI GS 

wells. See MSD Recommendation Letters dated December 23, 2008; May 14, 2009 and 

May 15, 2009. 

Individual Response: EPA acknowledges that Class II well operators have decades of experience 

injecting CO2. However, EPA believes that significant operational differences between Class II wells 

and Class VI wells to warrant tailored requirements for GS. 

EPA clarifies that the final GS rule contains risk based criteria at §144.19 to inform a Director’s 

determination to apply Class VI requirements to wells transitioning from an ER project to a project for 

254
which the primary purpose is long-term storage of CO2. For additional information on transitioning of 

Class II wells for GS, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28312 

Comment: Currently, it is unclear how Class II enhanced oil recovery wells or projects 

would be treated under the proposed waiver process. And the rules should include 

a mechanism to allow existing Class II wells injecting into receiving formations 

above the lower USDW to convert to Class VI wells absent a threat to drinking 

water. Under those circumstances, an automatic waiver or aquifer exemption may 

be appropriate. 

Individual Response: EPA disagrees that an "automatic" waiver is appropriate where wells are 

grandfathered. However, EPA agrees that there are situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs, as long 

as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which 

owners and operators can seek a waiver of the Class VI injection depth requirements. The purpose of 

the injection depth waiver requirements is to ensure protection of USDWs while allowing the use of GS 

capacity above and between USDWs if a site is suitable and all Class VI requirements are met. 

EPA clarifies that owners or operators seeking waivers from the injection depth requirements must 

provide additional information to ensure USDW protection. Specifically, they must submit a 

supplemental report (the GS Class VI injection depth waiver application report) referenced at 

§146.82(d) and outlined at §146.95(a) with additional, site-specific information, including: additional 

information about the injection zone; identification of confining units above and below the injection 

zone; tailored AoR modeling above and below the injection zone; a demonstration that well design is 

appropriate and protective of USDWs, in lieu of specific requirements at §146.86; a description of how 

monitoring will be tailored for injection above/between USDWs; and information about public water 

supplies in the AoR.

255
EPA clarifies that the final GS rule contains risk-based criteria at §144.19 to inform a Director’s 

determination to apply Class VI requirements to wells transitioning from an ER project to a project for 

which the primary purpose is long-term storage of CO2. For additional information on transitioning of 

Class II wells for GS, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3200 3.2. Comments on Alternative Injection Depth Waiver Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Pamela F. Faggert 

Commenter Organization: Dominion Resources Services, Inc. 

EPA Letter ID: 0358 

EPA Comment ID: 28235 

Comment: We commend EPA for its recognition in this NODA that a blanket prohibition 

related to injection depth would be problematic and for its attempt to provide 

needed flexibility into the process to consider project-specific siting issues 

through a waiver process. However, we believe that a removal of the blanket 

prohibition and an approach to consider siting on a case-by-case basis (without 

a specific requirement to obtain a waiver) would provide the same level of 

desired protection of USDWs that would be achieved through a waiver process. 

- Permit applicants will be required to submit detailed information in the 

permit application process and demonstrate that there will be no endangerment 

of USDWs regardless of whether a waiver is needed or not. Imposing the formality 

of a waiver may add an unnecessary administrative layer and regulatory hurdles 

256
to the process. 

- A waiver process would essentially assume, by default, that all projects 

injecting above the lowermost USDW pose a heightened risk to drinking water. 

This is likely to create unfavorable public perception issues. 

- We remain concerned that even EPA's waiver approach could eliminate vast 

storage formations that may be the only geographically feasible GS site for some 

sources of CO2 and will still be unnecessarily prohibitive of some safe EOR 

projects. Since EOR wells are likely the early adopters of GS, this could hamper 

commercial development of GS. 

To the extent the Agency retains a waiver provision, EPA should develop clear 

guidelines for decision makers in evaluating waiver applications as well as the 

development of a transparent process to provide guidance for future applicants. 

Individual Response: EPA agrees that a site-specific and flexible approach is appropriate, and 

believes that the requirements at §146.95 that allow injection above and between USDWs through the 

issuance of a waiver of the injection depth requirements for Class VI wells based on site-specific 

information will ensure USDW protection while allowing injection depth flexibility and use of varied 

formations and capacity. EPA adds that the waiver process will also increase public confidence in the 

process by providing a clear and transparent public notification process.

EPA agrees with the commenter that a waiver application process that is separate from the permit 

application is not necessary, and the final rule combines the application processes. Owners or 

operators seeking waivers must provide a supplemental report (the GS Class VI injection depth waiver 

application report) with their permit applications outlined at §146.95(a) with additional, site-specific 

information including: additional information about the injection zone; identification of confining units 

above and below the injection zone; tailored AoR modeling above and below the injection zone; a 

demonstration that well design is appropriate and protective of USDWs, in lieu of specific requirements 

at §146.86; a description of how monitoring will be tailored for injection above/between USDWs; and 

information about public water supplies in the AoR.

The Agency disagrees that a waiver process constitutes a default assumption that all projects above 

USDWs pose a heightened risk. Instead, the Agency believes that injection above and between USDWs 

warrants special considerations to ensure that injection operations do not endanger USDWs. 

The Agency disagrees that EPA is reducing capacity for GS, and believes the waiver approach responds 

to concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; allows for a more site-specific assessment of injection depth for GS 

257
projects; accommodates injection into different formation types. However, the primary focus of the GS 

rule is USDW protection and a GS project will not be issued a permit if it cannot be demonstrated that 

the injection will be protective of USDWs. 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28020 

Comment: 2. In many cases, a waiver may need to be accompanied by an aquifer exemption. 

Since no changes to the aquifer exemption criteria have been proposed, it appears 

that obtaining an exemption for USDW’s above the lowermost USDW for the purpose 

of geosequestration would not be possible unless the injection zone happens to 

qualify under one of the existing criteria in 40 CFR Part 146.4. In such 

circumstances this would create a prohibition for injection above the lowermost 

USDW regardless of whether or not a waiver process exists; 

Individual Response: EPA believes that there are limited circumstances where aquifer exemptions 

for GS may be warranted. The final rule allows for the expansion of the areal extent of existing aquifer 

exemptions for Class II EOR/EGR wells transitioning to Class VI injection for GS pursuant to 

requirements at §§146.4 and 144.7(d). 

The aquifer exemption requirements in the final rule provide flexibility and afford owners or operators 

an opportunity to assess and select a suitable GS site while also preserving USDWs (i.e., 

formations/aquifers afforded SDWA protection). Class VI owners or operators granted expansions of 

existing Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored 

requirements for GS wells in the final GS rule.

258
The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: B. Peter McGrail 

Commenter Organization: Pacific Northwest National Laboratory 

EPA Letter ID: 0375 

EPA Comment ID: 28161 

Comment: additional requirements outlined in this draft NODA. We strongly urge the EPA to 

draft a single and consistent set of requirements that all GS sequestration 

projects must meet to ensure site suitability. 

There is precedent supporting a single set of requirements approach. The 

European Union issued a directive in April 2009 that established the legal 

framework for the geological storage of CO2 (Directive 2009/31/EC). This 

directive delineates the objectives for GS projects that must be reached by 

member states in a reasonable time. However, each State is allowed to adapt its 

domestic law to the objectives of the directive. Several EU States, including 

the UK, have already endorsed most all of these objectives. 

The EU Directive concerning the selection of storage sites provides a list of 

criteria that must be fulfilled to determine if a geological formation is 

suitable or not. There are no constraining criteria in terms of depth 

relationships with any USDW. The potential storage complex and surrounding area 

must be characterized and article 4.4 says "A geological formation shall only be 

selected as a storage site if under the proper conditions of use there is no 

significant risk of leakage and if no environmental or health risk exists". 

There is no other constraint. Similarly, Australia was the first country in 2005 

to endorse new regulatory guidelines for CCS, and these guidelines do not impose 

depth criteria for the selection of suitable CO2 storage sites and further 

emphasize establishment of a consistent regulatory framework for CCS projects.[FOOTNOTE 1] 

259
Finally, new reservoir engineering approaches are being considered [FOOTNOTE 2] that 

eliminate a free CO2 phase in the target reservoir and thus could obviate 

virtually any risk to USDWs. Consequently, we emphasize again the importance of 

drafting a single set of consistent regulations that treat all potential 

geologic formations equally and without imposition of additional unwarranted and 

arbitrary requirements based on position in the subsurface with respect to 

USDWs. 

FOOTNOTE 1 - Carbon Dioxide Capture and Geological Storage, Australian 

Regulatory Guiding Principles, Ministerial Council on Mineral and Petroleum 

Resources, 2005. 

FOOTNOTE 2 - Burton, M. and S. L. Bryant. 2009. "Surface Dissolution: Minimizing 

Groundwater Impact and Leakage Risk Simultaneously." Energy Procedia 

1(1):3707-3714. 

Individual Response: EPA clarifies that GS projects that operate under injection depth waivers must 

meet the same requirements as other Class VI wells; the purpose of the waiver requirements at 

§146.95 is to provide additional considerations for wells injecting above or between USDWs to ensure 

protection of all USDWs. The waiver process allows for flexibility and does not preclude any 

formations, instead relying on site characterization, well construction, maintenance, monitoring, and 

post site closure care. 

EPA adds that it is monitoring the progress of international research and legislative developments; a 

paper summarizing EPA's research on international GS projects and legislation is in the rulemaking 

docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28092 

Comment: APC supports the concept of allowing injection above a USDW; however, we are 

concerned about the waiver process as currently designed. First, the EPA has not 

260
demonstrated how injection above a USDW presents an additional risk that would 

warrant a significant increase in the permitting requirements. If the proposed 

regulations are adopted, then a properly sited project will not pose any greater 

danger sited above a USDW as below one. Characterization of the confining zones 

will still be necessary whether they prevent against upward movement or downward 

movement. The regulations as proposed have been written broadly enough to 

require the site characterization to encompass both above and below a proposed 

injection zone, where appropriate. 

Individual Response: EPA believes that that injection for the purpose of GS into non-USDW 

formations above the lowermost USDW warrants tailored requirements to address the unique 

challenges and risks relative to injection below the lowermost USDW. For example, there is a risk of 

downward migration of fluids if there is no lower confining layer or inadequate confinement. In 

addition, there is potential that wells will be drilled through the injection zone in the future to reach 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements at §146.95 will provide additional 

considerations for the owner or operator and Director when permitting such wells to ensure protection 

of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27979 

Comment: Comment No. 36 

Page 44810 

Issue Topic from EPA's NODA 

Lastly, the approach is designed to acknowledge and accommodate comments and 

concerns about drinking water resource availability and the potential/known 

future needs, and to afford such water resources protection. 

261
Carbon Sequestration Council Comments 

EPA should clarify the scope and applicability of the proposed waiver process. 

First, EPA's intent appears to be to issue waivers only for situations where a 

more saline reservoir is overlying a USDW. These conditions are uncommon and 

would not address the problem faced in large portions of the western US where 

USDWs may extend from the surface to very great depths. To allow CCS in these 

regions, the waivers would necessarily have to authorize injection into USDWs 

above the lowermost USDW. Second, for the waiver system to work effectively, 

the final decision making authority for a waiver should be with the agency 

holding primacy for the proposed Class VI UIC program. 

Individual Response: EPA clarifies that injection depth waivers are necessary whenever owners or 

operators seek to inject CO2 for GS into non-USDWs that are above the lowermost formation 

containing a USDW or in between formations containing USDWs. Commenters on the proposed GS 

rule indicated that there are many circumstances, particularly in the western U.S., where there are 

deep USDWs and that the proposed injection depth requirements could preclude GS in certain regions 

of the country. These commenters also indicated that injection depth flexibility for GS is important to 

ensure that no parts of the country are excluded from GS activities and that CCS deployment is not 

restricted. The waiver process will allow injection into formations above the lowermost USDW if it can 

be demonstrated that the site is equally as protective of USDWs as injecting beneath the lowermost 

USDW. 

Regarding decisions on granting of injection depth waivers, EPA clarifies that the final determination 

regarding waiver issuance will be made by the Director, following evaluation of all site-specific 

information, public notice, and receipt of written concurrence or non-concurrence from the Regional 

Administrator. However, prior to a final decision, the Director must provide the Regional Administrator 

with the information collected during the waiver application and the public notice processes. Based on 

this information and pursuant to requirements at §146.95(d), the Regional Administrator will provide 

written concurrence or non-concurrence regarding waiver issuance. EPA believes Agency input is 

necessary in making injection depth waiver decisions and agrees with commenters who expressed 

interest in ensuring that multi-state boundary and water resource issues are addressed. The Agency 

also believes that Agency involvement in the waiver decision process will contribute to national 

consistency in waiver issuance. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

262
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28157 

Comment: Recommendation: We recommend that the waiver provision be made available to 

increase opportunities for GS. The waiver option should also apply to those 

aquifers that meet the criteria of 'exempted' aquifers at 40 CFR §146.4, and 

that no further 'exemption' should be required by US EPA. No separate aquifer 

'exemption' should be required for aquifers when an application for waiver has 

been accepted by the state. If an exemption is required by US EPA. we recommend 

that it not constitute a substantial program revision, and that the 

determination of exemption status be made by the Regional US EPA office. We also 

recommend that an additional exemption criteria be created under 40 CFR §146.4 

that provides for the exemption of aquifers for the purposes of geologic 

sequestration. 

Individual Response: EPA acknowledges that there are limited circumstances where aquifer 

exemptions for GS may be warranted. The final rule allows for the expansion of the areal extent of 

existing aquifer exemptions for Class II EOR/EGR wells transitioning to Class VI injection for GS 

pursuant to requirements at §§146.4 and 144.7(d). Class VI owners or operators granted expansions 

of existing Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored 

requirements for GS wells in the final GS rule. However, the final rule precludes the issuance of new 

aquifer exemptions for Class VI GS wells; that is, aquifer exemptions will only be granted for projects 

that are transitioning from Class II EOR/EGR wells to Class VI. 

The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances. 

The GS rule requires that all aquifer exemption expansion requests be treated as substantial program 

revisions under §145.32 and will require revision of Part 147. Furthermore, if EPA directly implements 

the UIC program in a State, an aquifer exemption expansion requires a revision to the UIC program of 

the applicable State under Part 147. 

EPA Team Member: 

263
Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28322 

Comment: API would encourage EPA to clarify the scope and applicability of the proposed 

waiver process. First, EPA's intent appears to be to issue waivers only in 

situations where a more saline reservoir is overlying a USDW. These conditions 

are relatively uncommon and would not address the problem faced in large 

portions of the western US where USDWs may extend from the surface to very great 

depths. To allow CCS in these regions, the waivers would necessarily have to 

authorize injection into USDWs above the lowermost USDW. 

Individual Response: EPA clarifies that injection depth waivers are necessary whenever owners or 

operators seek to inject CO2 for GS into non-USDWs that are above the lowermost formation 

containing a USDW or in between formations containing USDWs. Commenters on the proposed GS 

rule indicated that there are many circumstances, particularly in the western U.S., where there are 

deep USDWs and that the proposed injection depth requirements could preclude GS in certain regions 

of the country. These commenters also indicated that injection depth flexibility for GS is important to 

ensure that no parts of the country are excluded from GS activities and that CCS deployment is not 

restricted. The waiver process will allow injection into formations above the lowermost USDW if it can 

be demonstrated that the site is equally as protective of USDWs as injecting beneath the lowermost 

USDW. 

Regarding decisions on granting of injection depth waivers, EPA clarifies that the final determination 

regarding waiver issuance will be made by the Director, following evaluation of all site-specific 

information, public notice, and receipt of written concurrence or non-concurrence from the Regional 

Administrator. However, prior to a final decision, the Director must provide the Regional Administrator 

with the information collected during the waiver application and the public notice processes. Based on 

this information and pursuant to requirements at §146.95(d), the Regional Administrator will provide 

written concurrence or non-concurrence regarding waiver issuance. EPA believes Agency input is 

necessary in making injection depth waiver decisions and agrees with commenters who expressed 

interest in ensuring that multi-state boundary and water resource issues are addressed. The Agency 

also believes that Agency involvement in the waiver decision process will contribute to national 

264
consistency in waiver issuance. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3210 3.2.1. Comments Generally in Support of the Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: September 29, 2010 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28197 

Comment: 14. We support the view of some States that GS should be allowed where sitespecific demonstration is made that USDW will be protected -> even though depth 

criteria may not be in conformity with the basic rule requirement for injection 

below the lower most aquifer. A straightforward "waiver" process may serve in 

these cases. There should NOT be a blanket prohibition of injection above or 

between USDWs. 

Well completion technology and characterization of injection horizon and fluid 

interaction is a sufficiently developed state of the art to promote EPA’s 

"adaptive rule making." 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. 

265
EPA agrees that a flexible, site-specific approach to waiver determinations (and all Class VI permitting 

decisions) is appropriate. Site-specific demonstrations of injection zone integrity along with proper 

well construction, operation, monitoring, and post closure site care are the best way to ensure USDW 

safety while allowing flexibility for GS above or between USDWs. EPA believes that the additional 

requirements that apply to owners or operators of Class VI wells granted a waiver of the injection 

depth requirements will provide additional considerations for the owner or operator and Director when 

permitting such wells to ensure protection of all USDWs. EPA adds that all determinations regarding 

the appropriateness of a waiver will be made by the Director based on site-specific information. 

Additionally, the final GS rule does not categorically preclude or prohibit injection into any type of 

formation.

The Agency believes this approach: 1) responds to concerns about local and regional geologic storage 

capacity limitations imposed by the proposed injection depth requirements; 2) allows for a more sitespecific assessment of injection depth for GS projects; 3) accommodates injection into different 

formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between USDWs 

when appropriate and where it can be demonstrated that USDWs will be protected; and 5) responds to 

concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to addressing injection 

depth variability through a waiver process responds to concerns about future drinking water resource 

availability and the need to ensure that high quality water remains available in sufficient quantities to 

supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 28289 

Comment: EPA's more recent NODA [Footnote 4] proposes an alternative to the proposed 

depth-related prohibition. The NODA includes a waiver process whereby a State 

UIC Program Director could allow GS of CO2 in formations which are either 

relatively shallow (such as in coal seams or basalt structures), or which are 

above a very deep USDW. GS projects in states receiving such a waiver would 

need to provide additional, specific information to the UIC Program Director, 

demonstrating that the proposed project would not adversely impact USDW. 

266
[Footnote 4]: 74 FR 44802, August 31, 2009. 

While the waiver approach is preferred over a blanket prohibition, it is 

generally CURC's view that if EPA believes that the specified additional 

information submittals are necessary to protect USDW, the Agency should simply 

require their submittal for GS scenarios of concern, and adopt neither the 

general prohibition nor the waiver process. 

Individual Response: The final GS rule at §146.95 establishes a process by which owners and 

operators can seek a waiver of the Class VI injection depth requirements. The GS rule, at §146.95, 

contains additional requirements that apply to owners or operators of Class VI wells granted a waiver 

of the injection depth requirements. These additional requirements are tailored to ensure protection of 

all USDWs above and below the injection zone and are therefore not appropriate as a "default" for all 

Class VI wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Patrick J. Nugent 

Commenter Organization: Texas Pipeline Association (TPA) 

EPA Letter ID: 0340 

EPA Comment ID: 28013 

Comment: 1. TPA supports EPA's recognition that a case-by-case approach should be used in 

drafting geologic sequestration regulations. We are encouraged that EPA 

recognizes the benefits of "site-specific assessment" in this context. 74 Fed. 

Reg. 44810. In our December 12, 2008 comments, TPA emphasized that no two sites 

are alike and that a regulatory approach to geologic sequestration should be 

flexible so that site differences could be taken into account. Accordingly, we 

agree with and support EPA's proposal to make determinations in this context on 

a site-specific basis. We agree that regulators should have the flexibility to 

determine if "injection at a particular site and depth is the appropriate 

approach." Id. We believe that such an approach strikes the right balance by 

protecting underground sources of drinking water while allowing maximum use 

of geologic sequestration. We encourage EPA to apply the site-specific assessment 

267
Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. 

The final GS rule at §146.95 establishes a process by which owners and operators can seek a waiver 

of the Class VI injection depth requirements. EPA agrees that a flexible, site-specific approach to 

waiver determinations (and all Class VI permitting decisions) is appropriate. Site-specific 

demonstrations of injection zone integrity along with proper well construction, operation, monitoring, 

and post closure site care are the best way to ensure USDW safety while allowing flexibility for GS 

above or between USDWs. EPA believes that the additional requirements that apply to owners or 

operators of Class VI wells granted a waiver of the injection depth requirements will provide additional 

considerations for the owner or operator and Director when permitting such wells to ensure protection 

of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Patrick J. Nugent 

Commenter Organization: Texas Pipeline Association (TPA) 

EPA Letter ID: 0340 

EPA Comment ID: 28015 

Comment: 2. TPA supports EPA's proposal for a waiver process whereby injection above and 

between USDWs may be permitted. TPA agrees with and supports EPA's proposal to 

institute a waiver process concerning the depth at which geologic sequestration 

may occur. In our December 12, 2008 comments, TPA noted that the use of geologic 

sequestration would be unnecessarily hindered if EPA instituted an arbitrary, 

268
across-the-board prohibition on injection above a underground source of drinking 

water ("USDW"). TPA pointed out that, in some circumstances, it could be 

appropriate to allow injection above a USDW -for example, where the injection 

zone was far above a USDW and the characteristics of the intervening space 

prevented migration between the injection zone and the USDW. We also pointed out 

that carbon dioxide has been injected above the lowermost USDW without incident 

for decades in Texas, in connection with enhanced oil and gas recovery efforts. 

Accordingly, we are encouraged by the waiver proposal contained in the NODA. TPA 

believes that a site-specific, case-by-case approach should be used in 

determining the proper depth for carbon injection. In some cases it might be 

inappropriate to allow injection above a USDW, but in other cases injection 

above a USDW would be safe and would result in sequestration of a substantial 

amount of GHG that might otherwise be emitted into the atmosphere. The waiver 

proposal set forth in the NODA would enable a thorough and scientifically based 

assessment of the particular situation at issue. We support this approach and we 

encourage EPA to extend it to additional areas ofthe proposed rules. 

Individual Response: The final GS rule at §146.95 establishes a process by which owners and 

operators can seek a waiver of the Class VI injection depth requirements. EPA agrees that a flexible, 

site-specific approach to waiver determinations (and all Class VI permitting decisions) is appropriate. 

Site-specific demonstrations of injection zone integrity along with proper well construction, operation, 

monitoring, and post closure site care are the best way to ensure USDW safety while allowing 

flexibility for GS above or between USDWs. EPA believes that the additional requirements that apply to 

owners or operators of Class VI wells granted a waiver of the injection depth requirements will provide 

additional considerations for the owner or operator and Director when permitting such wells to ensure 

protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

269
Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27867 

Comment: The NDIC is strongly supportive of the increased flexibility to UIC Program 

Directors in this proposal. This will promote a common sense approach which 

allows consideration of local and regional geologic conditions for more sitespecific assessment and allows for injection into different formation types 

where appropriate based on regulatory flexibility. 

Individual Response: The final GS rule at §146.95 establishes a process by which owners and 

operators can seek a waiver of the Class VI injection depth requirements. EPA agrees that a flexible, 

site-specific approach to waiver determinations (and all Class VI permitting decisions) is appropriate. 

Site-specific demonstrations of injection zone integrity along with proper well construction, operation, 

monitoring, and post closure site care are the best way to ensure USDW safety while allowing 

flexibility for GS above or between USDWs. EPA believes that the additional requirements that apply to 

owners or operators of Class VI wells granted a waiver of the injection depth requirements will provide 

additional considerations for the owner or operator and Director when permitting such wells to ensure 

protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

270
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27868 

Comment: Injection of CO2 above the lowermost formation containing a USDW can be done 

safely where determined appropriate while protecting all USDWs. This is 

currently being done in enhanced oil recovery projects in the United States. In 

fact due to the buoyancy of CO2, there is less risk to USDWs below the injection 

zone. 

Injection of CO2 above the lowermost formation containing a USDW allows for 

injection into multiple stratified formations which allows for greater 

cumulative capacity. This may further reduce risk by maximizing the storage of 

each well and minimizing the number of wells penetrating confining zones or 

USDWs; these penetrations are one of the biggest risk factors. 

Accessing USDWs below a GS site is not technically challenging. Industry has 

developed the ability to safely drill through over-pressured reservoirs which 

may be analogous to GS sites. There are several formations in North Dakota 

which are over- pressured and the industry routinely can safely drill through 

these by taking the appropriate precautions. 

Individual Response: EPA agrees that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. 

EPA believes that that injection for the purpose of GS into non-USDW formations above the lowermost 

USDW warrants tailored requirements to address the unique challenges and risks relative to injection 

below the lowermost USDW. For example, there is a risk of downward migration of fluids if there is no 

lower confining layer or inadequate confinement. In addition, there is potential that wells will be drilled 

through the injection zone in the future to reach USDWs. EPA believes that the additional 

requirements that apply to owners or operators of Class VI wells granted a waiver of the injection 

depth requirements at §146.95 will provide additional considerations for the owner or operator and 

Director when permitting such wells to ensure protection of all USDWs.

EPA acknowledges that technologies exist to address the challenges associated with GS and injection 

271
that will be conducted under the waiver approach, e.g., to inject through over-pressured formations. 

However, EPA also believes that additional considerations are necessary when permitting such wells to 

ensure protection of all USDWs and that the additional requirements that apply to owners or operators 

of Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide this 

protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text that is later repeated in lines 50 to 54. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Olon Plunk 

Commenter Organization: Xcel Energy, Inc. 

EPA Letter ID: 0344 

EPA Comment ID: 27874 

Comment: Xcel Energy commends the EPA in its reconsideration of the originally proposed 

prohibition of CO2 injection into zones between and above the lowermost 

underground sources of drinking water (USDW). Our prior comments included 

discussion concerning the need for the EPA to avoid prohibitions that might 

stifle development of CO2 geological storage by implementing a "one size fits 

all" regulatory approach. As it was originally written, the prohibition would 

have excluded many parts of the country from CCS using geological storage. 

Xcel Energy believes that geological storage done on a case-by-case basis with a 

permitting process based on clear and appropriate parameters identified in the 

rules and that demonstrates the presence of suitable geologic characteristics 

that protect USDWs would be the preferred option. However, Xcel Energy 

recognizes that the proposed waiver process may provide a reasonable flexible 

compromise between the competing interests. 

Individual Response: The final GS rule at §146.95 establishes a process by which owners and 

operators can seek a waiver of the Class VI injection depth requirements. EPA agrees that a flexible, 

site-specific approach to waiver determinations (and all Class VI permitting decisions) is appropriate. 

Site-specific demonstrations of injection zone integrity along with proper well construction, operation, 

monitoring, and post closure site care are the best way to ensure USDW safety while allowing 

flexibility for GS above or between USDWs. EPA believes that the additional requirements that apply to 

owners or operators of Class VI wells granted a waiver of the injection depth requirements will provide 

272
additional considerations for the owner or operator and Director when permitting such wells to ensure 

protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27880 

Comment: AEP supports EPA's suggestion to adopt a flexible waiver process to allow for 

CO2OS injection above and between underground sources of drinking water (USDWs). 

74 Fed. Reg. at 44810. As stated in the NODA, EPA's original proposal to define 

Class VI injection wells as those used for injection of CO2 beneath the 

lowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

rendering impossible CO2 GS sites in large areas of the country with deep USDWs. 

74 Fed. Reg. at 44808. The proposal would also prohibit CO2 injection into many 

shallow formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As the 

NODA observes, a number of states have indicated that regions with very deep and 

layered USDWs could not undertake CO2 GS projects because injectors could not 

comply with the proposed injection depth and well construction requirements. 74 

Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement, but allow owners or operators 

to apply for a site-specific waiver from those injection depth requirements upon 

273
making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. AEP believes that such a flexible approach would ensure adequate 

protection of USDWs while recognizing the vast geographic and topographic 

differences between potential C02 GS sites throughout the country, allowing for 

maximization of safe C02 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. 

The final GS rule at §146.95 establishes a process by which owners and operators can seek a waiver 

of the Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara A. Walz 

Commenter Organization: Tri-State Generation and Transmission Association, Inc. (Tri-State) 

EPA Letter ID: 0346 

EPA Comment ID: 27889 

Comment: Tri-State supports EPA's suggestion to adopt a flexible waiver process to allow 

for CO2 GS injection above and between underground sources of drinking water 

(USDWs) [74 Fed. Reg. at 44810). As stated in the NODA, EPA's original proposal 

to define Class VI injection wells as those used for injection of C02 beneath 

the lowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

274
rendering impossible CO2 GS sites in large areas of the country with deep USDWs 

[74 Fed. Reg. at 44808). The original proposal would also prohibit CO2 injection 

into many shallow formations such as coal seams and basalts [73 Fed. Reg. at 

43512). As the NODA observes, a number of states have indicated that regions 

with very deep and layered USDWs could not undertake CO2 GS projects because 

injectors could not comply with the proposed injection depth and well 

construction requirements [74 Fed. Reg. at 44809). 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement, but allow owners or operators 

to apply for a site-specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

protects public health and USDWs [Id. at 44810). Tri-State believes that such a 

flexible approach would ensure adequate protection of USDWs while recognizing 

the vast geographic and topographic differences between potential CO2 GS sites 

throughout the country, allowing for maximization of safe CO2 storage capacity 

nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James F. Stine 

275
Commenter Organization: National Rural Electric Cooperative Association 

EPA Letter ID: 0348 

EPA Comment ID: 27905 

Comment: NRECA supports EPA's suggestion to adopt a flexible waiver process to allow for 

CO2 GS injection above and between underground sources of drinking water 

(USDWs). 74 Fed. Reg. at 44810. As we stated in our previous comments, EPA's 

original proposal to define Class VI injection wells as those used for injection 

of CO2 beneath the lowermost formation containing a USDW would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

rendering impossible CO2 GS sites in large areas of the country with deep USDWs. 

EPA's initial proposal would also prohibit CO2 injection into many shallow 

formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As the NODA 

observes, a number of states have indicated that regions with very deep and 

layered USDWs could not undertake CO2 GS projects because injectors could not 

comply with the proposed injection depth and well construction requirements. 74 

Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site-specific waiver from those injection depth requirements upon 

making a demonstration that such injection EPA addresses these concerns by the 

proposal set forth in the NODA to keep the originally proposed injection depth 

requirement but allow owners or operators to apply for a site-specific waiver 

from those injection depth requirements upon making a demonstration that such 

injection can be undertaken in a manner that prevents the endangerment of public 

health from USDW contamination. Id. at 44810. NRECA believes that such a 

flexible approach would ensure adequate protection of USDWs while recognizing 

the vast geographic and topographic differences between potential CO2 GS sites 

throughout the country, allowing for maximization of safe CO2 storage capacity 

nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

276
projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James R. Roewer 

Commenter Organization: Utility Solid Waste Activities Group (USWAG) 

EPA Letter ID: 0349 

EPA Comment ID: 28034 

Comment: Specifically, USWAG supports EPA's suggestion to adopt a flexible waiver process 

to allow for CO2 GS injection above and between underground sources of drinking 

water (USDWs). 74 Fed. Reg. at 44810. As stated in the NODA, EPA's original 

proposal to define Class VI injection wells as those used for injection of CO2 

beneath the lowermost formation containing a USDW (73 Fed. Reg. at 43511) would 

preclude injection of CO2 into zones between and above USDWs, thereby 

restricting or rendering impossible CO2 GS sites in large areas of the country 

with deep USDWs. 74 Fed. Reg. at 44808. The proposal would also prohibit CO2 

injection into many shallow formations such as coal seams and basalts. 73 Fed. 

Reg. at 43512. As the NODA observes, a number of states have indicated that 

regions with very deep and layered USDWs could not undertake CO2 GS projects 

because injectors could not comply with the proposed injection depth and well 

construction requirements. 74 Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site- specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. USWAG believes that such a flexible approach would ensure adequate 

protection of USDWs while recognizing the vast geographic and topographic 

differences between potential CO2 GS sites throughout the country, allowing for 

277
maximization of safe CO2 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28044 

Comment: API is supportive of EPA's effort to introduce flexibility on the depth of 

injection relative to the location of USDWs by proposing a waiver process. API 

holds that CO2 can be injected above a USDW while protecting the USDW and 

maintaining access to the USDW for future use. As noted in API's testimony last 

year, the Salt Creek EOR project in Wyoming, which has a USDW below the 

injection zone, is an excellent example of how industry can operate CO2 

injection wells in an EOR context without endangering or limiting access to 

USDWs that are located below the injection zone. Accessing USDWs below a 

storage site, while not trivial, does not present significant technological 

hurdles. Industry has the technology and experience needed to drill through 

over-pressured gas reservoirs which are analogous to GS sites. There are some 

excellent examples of off-shore technologies for drilling through salt 

278
formations and shallow gas pockets that involve the same type of pressure issues 

that would be encountered in drilling through a GS site. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA agrees with the commenter that technologies exist to address the challenges associated with GS 

and injection that will be conducted under the waiver approach, e.g., to inject through overpressurized reservoirs. However, EPA also believes that additional considerations are necessary when 

permitting such wells to ensure protection of all USDWs and that the additional requirements that 

apply to owners or operators of Class VI wells granted a waiver of the injection depth requirements at 

§146.95 will provide this protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text that is later repeated in lines 290 to 296. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Claire M. Olson 

Commenter Organization: Basin Electric Power Cooperative (Basin Electric) 

EPA Letter ID: 0351 

EPA Comment ID: 28055 

Comment: Basin Electric supports EPA's suggestion to adopt a flexible waiver process to 

allow for CO2 GS injection above and between underground sources of drinking 

water (USDWs). 74 Fed. Reg. at 44810. As stated in the NODA, EPA's original 

279
proposal to define Class VI injection wells as those used for injection of CO2 

beneath the lowermost formation containing a USDW (73 Fed. Reg. at 43511) would 

preclude injection of CO2 into zones between and above USDWs, thereby 

restricting or rendering impossible CO2 GS sites in large areas of the country 

with deep USDWs. 74 Fed.Reg. at 44808. The proposal would also prohibit CO2 

injection into many shallow formations such as coal seams and basalts. 73 Fed. 

Reg. at 43512. As the NODA observes, a number of states have indicated that 

regions with very deep and layered USDWs could not undertake CO2 GS projects 

because injectors could not comply with the proposed injection depth and well 

construction requirements. 74 Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site-specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. Basin Electric believes that such a flexible approach would ensure 

adequate protection of USDWs while recognizing the vast geographic and 

topographic differences between potential CO2 GS sites throughout the country, 

allowing for maximization of safe CO2 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

280
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28072 

Comment: We support EPA's suggestion to adopt a flexible waiver process to allow for C02 

as injection above and between underground sources of drinking water ("USDWs"). 

74 Fed. Reg. at 44810. As stated in the NODA, EPA's original proposal to define 

Class VI injection wells as those used for injection of CO2 beneath the 

lowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

rendering impossible C02 as sites in large areas of the country with deep USDWs. 

74 Fed. Reg. at 44808. The proposal would also prohibit CO2 injection into many 

shallow formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As the 

NODA observes, a number of states have indicated that regions with very deep and 

layered USDWs could not undertake CO2as projects because injectors could not 

comply with the proposed injection depth and well construction requirements. 74 

Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site-specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. Ameren believes that such a flexible approach would ensure adequate 

protection of USDWs while recognizing the vast geographic and topographic 

differences between potential C02 as sites throughout the country, allowing for 

maximization of safe CO2 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

281
GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28078 

Comment: EPRI COMMENT#1: The NODA provides a waiver process in which a project proponent 

can submit a permit application for the injection of CO2 above the lowermost 

Underground Source of Drinking Water (USDW). EPRI supports the EPA’s decision to 

create the waiver process because it provides greater flexibility in selecting 

injection sites that meet all of the proposed technical requirements of a Class 

VI injection permit, except for depth. EPRI agrees that protection of USDWs can 

be accomplished regardless of injection depth by selecting and permitting sites 

with competent confining units that will isolate the injected CO2 from the 

adjacent USDW(s). 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

282
that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28086 

Comment: In summary, EPRI believes that the above additional requirements proposed for 

the waiver process, as well as those for enhanced construction and operational 

requirements and type of monitoring technology to be deployed, address concerns 

that are already covered by the July 2008 draft rule, with one exception. We 

agree with EPA’s proposed requirement for monitoring in the USDW below the 

injection zone when injecting CO2 above the lowermost USDW. 

Individual Response: EPA agrees that site specific demonstrations of injection zone integrity along 

with proper well construction, operation, monitoring, and post-injection site care as required in the GS 

rule, are appropriate to ensure USDW protection while allowing GS. 

EPA acknowledges the commenter's support of the waiver approach and site-specific flexibility in 

regulatory development and permitting as described in the NODA and Request for Comment. The 

Agency acknowledges that there are some situations where injection into non-USDW formations above 

the lowermost USDW can be performed in a manner that protects USDWs. 

The final GS rule at §146.95 establishes a process by which owners and operators can seek a waiver 

of the Class VI injection depth requirements and includes additional requirements, such as monitoring 

above and below the injection zone, to ensure USDWs are protected from endangerment. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John A. Gulvas 

Commenter Organization: Consumers Energy (CE) 

283
EPA Letter ID: 0356 

EPA Comment ID: 28088 

Comment: CE also supports EPA’s suggestion to adopt a flexible waiver process to allow 

for CO2 GS injection above and between underground sources of drinking water 

(USDWs). 74 Fed. Reg. at 44810. As stated in the NODA, EPA’s original proposal 

to define Class VI injection wells as those used for injection of CO2 beneath 

the lowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

rendering impossible CO2 GS sites in large areas of the country with deep USDWs. 

74 Fed. Reg. at 44808. The proposal would also prohibit CO2 injection into many 

shallow formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As the 

NODA observes, a number of states have indicated that regions with very deep and 

layered USDWs could not undertake CO2 GS projects because injectors could not 

comply with the proposed injection depth and well construction requirements. 74 

Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site-specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. CE believes that such a flexible approach would ensure adequate 

protection of USDWs while recognizing the vast geographic and topographic 

differences between potential CO2 GS sites throughout the country, allowing for 

maximization of safe CO2 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

284
that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28221 

Comment: In August, 2009. EPA announced a proposed supplement to the 2008 proposal. We 

applaud EPA for its improvements to the rule in three main areas: 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high-quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

285
EPA Letter ID: 0360 

EPA Comment ID: 28241 

Comment: NRG supports EPA’s suggestion to adopt a flexible waiver process to allow for 

CO2 GS injection above and between underground sources of drinking water 

(USDWs). 74 Fed. Reg. at 44810. As stated in the NODA, EPA’s original proposal 

to define Class VI injection wells as those used for injection of CO2 beneath 

the lowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude 

injection of CO2 into zones between and above USDWs, thereby restricting or 

rendering impossible CO2 GS sites in large areas of the country with deep USDWs. 

74 Fed. Reg. at 44808. The proposal would also prohibit CO2 injection into many 

shallow formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As 

the NODA observes, a number of states have indicated that regions with very deep 

and layered USDWs could not undertake CO2 GS projects because injectors could 

not comply with the proposed injection depth and well construction requirements. 

74 Fed. Reg. at 44809. 

EPA addresses these concerns by the proposal set forth in the NODA to keep the 

originally proposed injection depth requirement but allow owners or operators to 

apply for a site- specific waiver from those injection depth requirements upon 

making a demonstration that such injection can be undertaken in a manner that 

prevents the endangerment of public health from USDW contamination. Id. at 

44810. NRG believes that such a flexible approach would ensure adequate 

protection of USDWs while recognizing the vast geographic and topographic 

differences between potential CO2 GS sites throughout the country, allowing for 

maximization of safe CO2 storage capacity nationwide. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

286
that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28258 

Comment: The realization of CCS's full potential depends upon development of clear, yet 

flexible, regulations. In particular, appropriate provisions related to project 

siting are important to achieve the twin goals of facilitating development of 

commercial CCS projects, including EOR projects, and simultaneously protecting 

against threats to underground sources of drinking water (USDW). The NODA's 

contemplated changes to the proposed rules' ban on injection above the lowermost 

USDW, which would allow such injection where a waiver is obtained, mark a step 

in the direction of this needed flexibility. While NACCSA would prefer 

individualized siting decisions that include no predetermined limitations on 

receiving formations, NACCSA commends the Agency's efforts to allow for 

consideration of site- and project-specific factors in siting GS projects 

through this concept of a waiver. NACCSA also submits specific comments 

regarding how flexibility and clarity may best be achieved and suggested 

improvements to the waiver concept, in particular improvements needed to provide 

support for EOR projects, should the Agency decide to retain the prohibition on 

injection above the lowermost USDW as a default concept. 

Individual Response: The final GS rule at §146.95 establishes a process by which owners and 

operators can seek a waiver of the Class VI injection depth requirements. EPA agrees that a flexible, 

site-specific approach to waiver determinations (and all Class VI permitting decisions) is appropriate. 

Site-specific demonstrations of injection zone integrity along with proper well construction, operation, 

monitoring, and post closure site care are the best way to ensure USDW safety while allowing 

flexibility for GS above or between USDWs. EPA believes that the additional requirements that apply to 

owners or operators of Class VI wells granted a waiver of the injection depth requirements will provide 

additional considerations for the owner or operator and Director when permitting such wells to ensure 

protection of all USDWs. 

287
The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

For additional information on transitioning Class II wells for GS, see the preamble to the final rule and 

the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28263 

Comment: After consideration of such comments and others, the Agency now proposes an 

approach that would retain the prohibition on injection and storage above the 

lowermost USDW, but provide for a waiver process to allow injection above the 

lowermost USDW in circumstances in which there are "deep USDWs." NACCSA believes 

that making siting determinations on a case-by- case basis without any default 

prohibition would achieve the same level protection for USDW as imposition of a 

waiver process without introduction of additional regulatory obstacles for 

potential permitees. Nonetheless, NACCSA commends the Agency's revised proposal 

for recognizing that a total ban on injection above the lowermost USDW is not 

warranted and for moving in the direction of site-specific analysis. 

Appropriately crafted, a waiver concept may allay many concerns associated with 

a total ban and allow for site- and project-specific flexibility. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

288
formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. EPA agrees that a flexible, site-specific approach to waiver 

determinations (and all Class VI permitting decisions) is appropriate. Site-specific demonstrations of 

injection zone integrity along with proper well construction, operation, monitoring, and post closure 

site care are the best way to ensure USDW safety while allowing flexibility for GS above or between 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements will provide additional considerations for 

the owner or operator and Director when permitting such wells to ensure protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28275 

Comment: APS supports EPA's proposal to adopt a flexible waiver process to allow for CO2 

sequestration above and between underground sources of drinking water (USDWs). 

74 Fed. Reg. at 44810. In Arizona we are just beginning to investigate the 

potential for geologic storage sites. In the case of the project at our Cholla 

Power Plant, C02 injection was planned below any USDW. However, to the north of 

our plant favorable geologic storage sites may be located between USDWs. The 

data on water quality is sparse in these deeper units. Allowing for a waiver 

gives us increased flexibility to pursue good storage sites that are not beneath 

all USDWs. 

289
Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. EPA agrees that a flexible, site-specific approach to waiver 

determinations (and all Class VI permitting decisions) is appropriate. Site-specific demonstrations of 

injection zone integrity along with proper well construction, operation, monitoring, and post closure 

site care are the best way to ensure USDW safety while allowing flexibility for GS above or between 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements will provide additional considerations for 

the owner or operator and Director when permitting such wells to ensure protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Stroben 

Commenter Organization: Duke Energy Corporation 

EPA Letter ID: 0368 

EPA Comment ID: 27928 

Comment: In its July 25, 2008 proposal, EPA proposed a blanket prohibition on injecting 

CO2 into formations which were either not far enough below an Underground Source 

of Drinking Water (USDW), or above a very deep USDW. In its August 31, 2009 

NODA, EPA indicates that it is now considering an injection depth waiver process 

to allow GS injection above and between USDWs under specific conditions in lieu 

of a blanket prohibition. Duke Energy views EPA's consideration of new 

information and data from comments received, and its resulting proposal to 

290
consider an injection depth waiver process as a positive step and Duke Energy 

commends EPA for its action. A blanket prohibition related to injection depth 

would be problematic and unnecessary. An appropriately designed injection depth 

waiver process [FOOTNOTE 1] will add flexibility to a GS regulatory program by allowing 

site-specific factors to inform project siting and design decisions, thus 

avoiding unnecessary regulatory burdens, but still ensuring that potentially 

undesirable impacts to UDWS are avoided. 

FOOTNOTE 1 - The waiver process itself must be workable to be of any practical 

value in providing flexibility to the GS program and to GS project developers. 

While the waiver process must ensure that potentially undesirable impacts to 

UDSW are avoided, the process must also avoid being so complex that it becomes 

too burdensome for project developers to use and as a result provide no 

flexibility to the GS program. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. EPA agrees that a flexible, site-specific approach to waiver 

determinations (and all Class VI permitting decisions) is appropriate. Site-specific demonstrations of 

injection zone integrity along with proper well construction, operation, monitoring, and post closure 

site care are the best way to ensure USDW safety while allowing flexibility for GS above or between 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements will provide additional considerations for 

the owner or operator and Director when permitting such wells to ensure protection of all USDWs. 

The Agency believes the waiver approach: 1) responds to concerns about local and regional geologic 

storage capacity limitations imposed by the proposed injection depth requirements; 2) allows for a 

more site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or between 

USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) 

responds to concerns about the use of aquifer exemptions for GS. Finally, EPA's approach to 

addressing injection depth variability through a waiver process responds to concerns about future 

drinking water resource availability and the need to ensure that high quality water remains available in 

sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

291
Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28018 

Comment: In principal, the committee does not disagree with EPA’s proposal to establish a 

waiver process for the purpose of allowing injection of CO2 into zones above the 

lowermost Underground Source of Drinking Water (USDW). However, we have several 

concerns about the requirements `of such a process as follows: 

Individual Response: EPA acknowledges that there are some situations where injection into nonUSDW formations above the lowermost USDW can be performed in a manner that protects USDWs. 

The final GS rule at §146.95 establishes a process by which owners and operators can seek a waiver 

of the Class VI injection depth requirements. Please see EPA's specific responses below. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Smith 

Commenter Organization: Questar Exploration & Production Company 

EPA Letter ID: 0374 

EPA Comment ID: 28118 

Comment: Questar appreciates EPA's Willingness to reassess its initial prohibition of 

injection to formations below the lowermost USDW. As stated in the API comments, 

that proposal was "not necessary for the protection of USDWs and would remove a 

significant number of viable formations from consideration as GS sites," using 

the Salt Creek EOR project in Wyoming as an example. Therefore, Questar supports 

the availability of a waiver provision so long as it is workable and available 

in practice. Including the Public Water Supply Supervision (PWSS) Program 

292
Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs.

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28174 

Comment: 2. CO2 Sequestration Should be Allowed Above the Lowermost USDW, But Only Where 

the Geology is Sufficiently Protective, and the Permit Contains Adequate 

Requirements 

EPA seeks comment on the alternative idea of a "waiver" process, wherein the 

Director might grant site-specific exemptions from the general prohibition on 

injection above the lowermost USDW. We support this idea generally. As we 

described in our comments on the NOPR, [FOOTNOTE 14] GS reservoirs located above 

lowermost USDWs may or may not present additional risks than sites located below 

293
the lowermost USDWs, and establishing safe and effective siting and operations 

should be based on additional considerations. At the same time, we recognize 

that there are many potentially excellent sequestration sites above USDWs, and 

that in some areas of the country, these may be the only sites available. 

FOOTNOTE 14 - Id. at 12. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs.

EPA believes that that injection for the purpose of GS into non-USDW formations above the lowermost 

USDW warrants tailored requirements to address the unique challenges and risks relative to injection 

below the lowermost USDW. For example, there is a risk of downward migration of fluids if there is no 

lower confining layer or inadequate confinement. In addition, there is potential that wells will be drilled 

through the injection zone in the future to reach USDWs. EPA believes that the additional 

requirements that apply to owners or operators of Class VI wells granted a waiver of the injection 

depth requirements at §146.95 will provide additional considerations for the owner or operator and 

Director when permitting such wells to ensure protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Stan Belieu 

Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC) 

294
EPA Letter ID: 0378 

EPA Comment ID: 28182 

Comment: The NOGCC is strongly supportive of the increased flexibility to UIC Program 

Directors in this proposal. This will promote a common sense approach which 

allows consideration of local and regional geologic conditions for more sitespecific assessment and allows for injection into appropriate formation types, 

based on quality of a particular geologic basin. 

NOGCC houses what we believe is the most encompassing library of sub-surface 

geologic data in the state of Nebraska, base on our knowledge of the geology of 

Nebraska, without regulatory flexibility, GS would not be possible in most of 

state, as USDWs are present through the entire geological stratigraphic column 

to the pre-Cambrian basement. 

The injection of CO2 above the lowermost formation containing a USDW can be done 

safely where determined appropriate while protecting all USDWs. This is 

currently being done in enhanced oil recovery projects in Nebraska and 

throughout the United States. In fact due to the buoyancy of CO2, there is less 

risk to USDWs below the injection zone. 

Injection of CO2 above the lowermost formation containing a USDW allows for 

injection into multiple stratified formations which allows for greater 

cumulative capacity. This may further reduce risk by maximizing the storage of 

each well and minimizing the number of wells penetrating confining zones or 

USDWs; these penetrations are one of the biggest risk factors. 

Accessing USDWs below a GS site is not technically challenging. Industry has 

developed the ability to safely drill through over-pressured reservoirs which 

may be analogous to GS sites. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. 

EPA also agrees that technologies exist to address the challenges associated with GS and injection 

that will be conducted under the waiver approach, e.g., to inject through over-pressurized reservoirs. 

295
However, EPA also believes that additional considerations are necessary when permitting such wells to 

ensure protection of all USDWs and that the additional requirements that apply to owners or operators 

of Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide this 

protection. 

Furthermore, EPA believes that the requirements at §146.95 address potential risks associated with 

injection into non-USDW formations above the lowermost USDW. These may include the risk of 

downward migration of fluids if there is no lower confining layer or inadequate confinement. In 

addition, there is the potential that wells will be drilled through the injection zone in the future to 

reach the USDW. EPA believes that the additional requirements that apply to owners or operators of 

Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide additional 

considerations for owners or operators and Directors when permitting such wells to ensure protection 

of all USDWs.

Regarding the comment on consideration of distance, EPA believes that suitable confining layers (e.g., 

low-permeability, low-porosity formations identified through proper site characterization process) 

along with proper well construction, operation, monitoring, and post-injection site care are key to 

protecting USDWs from endangerment. Additionally, the Agency believes that distance between the 

injection zone and USDWs can impede vertical fluid movement, allow for pressure dissipation, and 

provide additional sites for monitoring, mitigation, and remediation if conditions warrant. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text that is later repeated in lines 56 to 58. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28091 

Other EPA Comment Codes and Descriptions: 3420 3.4.2. Request for Information on Areas 

Where Injection Depth and USDWs Are a Concern (seeking comment) 

Comment: Injection Depth for GS Projects 

APC is supportive of EPA’s effort to introduce flexibility on the depth of 

injection relative to the location of USDWs. APC holds that CO2 can be injected 

above a USDW while protecting the USDW and maintaining access to the USDW for 

future use. Anadarko’s Salt Creek EOR project in Wyoming, which has a USDW below 

296
the injection zone, is an excellent example of how industry can operate CO2 

injection wells in an EOR context without endangering or limiting access to 

USDWs that are located below the injection zone. Accessing USDWs below a CCS 

site does not present significant technological hurdles. Industry has the 

technology to drill through over-pressured gas reservoirs which are analogous to 

CCS sites. There are some excellent examples of off-shore technologies for 

drilling through salt formations and shallow gas pockets that involve the same 

type of pressure issues that would be encountered in drilling through a CCS 

site. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs.

EPA acknowledges that technologies and past experience exist to inject through over-pressured 

formations while maintaining zonal isolation (e.g., oil and gas industry experience in drilling through 

shallow pockets of gas or other zones that have higher pressures). EPA has reviewed information on 

these types of projects and has determined that, if properly constructed, wells can be drilled through 

pressurized zones without causing fluid movement. However, to provide additional USDW protection 

and ensure that any planned drilling is conducted appropriately, the final GS rule requires the Director 

to consider planned or permitted water, hydrocarbon, or mineral resource exploitation potential of the 

proposed injection formation and other formations both above and below the injection zone to 

determine if there are any plans to drill through the formation to access resources in or beneath the 

proposed injection zone/formation as specified in §146.95(b)(1)(vii). EPA believes that these 

additional considerations are necessary when permitting such wells to ensure protection of all USDWs 

and that the additional requirements that apply to owners or operators of Class VI wells granted a 

waiver of the injection depth requirements at §146.95 will provide this protection. 

EPA Team Member: 

Draft Status: 

297
Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27975 

Comment: Comment No. 32 

Page 44809 

Issue Topic from EPA's NODA 

Certain States have indicated that where USDWs are very deep (e.g., 15,000 

ft/4,572 meters and deeper) and layered (stratified) these regions would become 

unavailable for large- scale GS projects because injectors would not be able to 

comply with the current injection depth (and well construction) requirements. 

These States suggest that GS should be allowed in certain areas if a sitespecific demonstration can be made that USDWs will be protected. 

Carbon Sequestration Council Comments 

We support the provision to allow CO2 injection into formations above the 

lowermost USDW when adequate containment of injected CO2 and protection of USDWs 

can be demonstrated. As noted in our comments of December 24, 2008, we would 

prefer to have the necessary criteria for GS project siting and containment 

demonstration built into the normal permitting process, where these requirements 

would be routinely applicable whenever a permit applicant is proposing to inject 

into a saline formation that is above the lowermost USDW. The permitting process 

- with the notice, comment, hearing and permitting provisions we support - would 

provide adequately for consideration of the necessary technical issues. 

Nevertheless, we also believe that the concept of a site-specific waiver process 

for geologic storage above the lowermost USDW can be made workable but requires 

some improvements which are specifically noted in these Comments. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

298
Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28122 

Comment: In addition, we commend the Agency for its careful reconsideration of the 

originally- proposed prohibition on injection and storage above the lowermost 

underground source of drinking water (USDW) and its revised proposal to allow 

injection and storage above the lowermost USDW where a waiver is obtained. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

299
demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28124 

Comment: Accordingly, a blanket prohibition on the use of potential receiving 

formations above the lowermost USDW, even where regulatory provisions for a 

waiver are available, is unnecessary. However, allowing for a transparent, 

outcome-predictable waiver process that works within the current definition of 

USDW would ameliorate many of the concerns associated with limiting injection and 

storage to formations below the lowermost USDW. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. 

EPA believes that through the waiver process, the GS rule avoids a "blanket prohibition" of injection 

into any formation types, so long as the injection is demonstrated to be protective of USDWs. The final 

GS rule maintains the principles of site-suitability and flexibility and does not categorically preclude or 

prohibit injection into any type of formation. Instead, the requirements are designed to ensure 

protection of USDWs through proper siting, well construction, operation, monitoring, and postinjection site care at all sites selected for GS. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

300
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28129 

Comment: Such a limitation on receiving formations would be unnecessary, unduly 

burdensome, and undesirable for several reasons: 

-A categorical elimination of certain potential receiving formations is 

unnecessary in light of the overall function of the UIC rules, which require all 

permit applicants to demonstrate that projects will not endanger USDW. Further, 

the proposed rules would require permittees to demonstrate the presence of a 

"suitable geologic system" for a project. The suitability of any particular 

receiving formation will thus necessarily be evaluated for each project. 

-Each project and project site will possess its own unique characteristics. For 

sites that would require injection above the lowermost USDW, there may exist 

other characteristics that would provide equivalent or greater protection for 

USDW. 

-Limitations on injection above the lowermost USDW is currently imposed only on 

Class I hazardous waste injection wells. As carbon dioxide is not a hazardous 

waste, imposing an identical requirement for CO2 injection wells is likely to 

create public misperceptions concerning the safety of GS projects. 

-Limitations on injection above the lowermost USDW also may serve to exclude oil 

and gas reservoirs as potential CO2 receiving formations. 

The appropriateness of any given receiving formation more appropriately would be 

considered on a case-by-case basis in light of the geologic characteristics of a 

given project and based on the application of clear and appropriate parameters 

set forth in the rules. In response to such comments, the Agency now seeks 

comment on regulations that would retain the prohibition on injection and 

storage above the lowermost USDW, but provide for a waiver process to account 

for circumstances in which there are deep USDW. 

Eliminating the default prohibition and making siting determinations on a caseby-case basis as outlined above would achieve the same level protection for 

USDWs as the imposition of a waiver process (which could be interpreted as a 

301
baseline assumption that all projects injecting above the lowermost USDW pose 

some heightened risk to drinking water), without the addition of unnecessary 

regulatory hurdles. Nevertheless, EEI commends the Agency’s revised proposal 

for its recognition that a blanket prohibition related to injection depth would 

be problematic and unnecessary, and recognizes that a waiver procedure may 

provide a workable compromise for the competing interests evidenced in the 

comments. The contemplated waiver process is an example of how the Agency may 

insert needed flexibility into the process to take into account project-specific 

siting and other issues while ensuring the continued protection of USDW. 

Individual Response: EPA agrees that a flexible, site-specific approach to waiver determinations 

(and all Class VI permitting decisions) is appropriate. The final GS rule at §146.95 establishes a 

process by which owners and operators can seek a waiver of the Class VI injection depth 

requirements. Site-specific demonstrations of injection zone integrity along with proper well 

construction, operation, monitoring, and post closure site care are the best way to ensure USDW 

safety while allowing flexibility for GS above or between USDWs. EPA believes that the additional 

requirements that apply to owners or operators of Class VI wells granted a waiver of the injection 

depth requirements will provide additional considerations for the owner or operator and Director when 

permitting such wells to ensure protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28130 

Other EPA Comment Codes and Descriptions: 3310 3.3.1. Site Characterization 

Comment: Fundamentally, proper site selection is critical to a successful GS project. 

Indeed, proper site characterization is the most effective risk management tool 

for GS projects. It serves to minimize, if not eliminate, any potential threats 

to USDW that GS projects may pose. EEI maintains that siting decisions may best 

be made on a project-by- project basis through exercise of the program 

director’s discretion bounded by clear principles for its application, and that 

a blanket prohibition on use of potential receiving formations above the 

lowermost USDW, even where regulatory provisions for a waiver are available, is 

302
unnecessary. However, allowing for a waiver process would ameliorate many of 

EEI’s concerns with limiting injection and storage to formations below the 

lowermost USDW. 

Individual Response: EPA agrees that proper site selection, along with proper well construction, 

operation, monitoring, and post-injection site care, are critical components of a GS project. EPA 

clarifies that the requirements at §146.95 for owners and operators seeking injection depth waivers 

are intended to add to and modify the requirements that all GS well owners or operators must meet, 

including those for site-specific geologic characterization, to ensure that the proposed site is evaluated 

in the context of the presence of USDWs above and below the injection zone. EPA anticipates that 

issuance of waivers will be limited to circumstances where there are deep USDWs and/or where the 

lack of a waiver of injection depth requirements would result in impractical or technically infeasible 

well construction, and where USDW protection is demonstrated and maintained through the life of the 

GS project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28153 

Comment: EPA’s proposed waiver process for injection below the lowermost USDW is sound in 

principle but needs revisions. First, the waiver application should be submitted 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

303
demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28154 

Comment: Comment: Waiver process to allow geologic sequestration (GS) of CO2 above and 

between USDWs 

We appreciate EPA's analysis of the benefits that can accrue toward CO2 

sequestration at the national level by providing states additional flexibility 

in selecting suitable and preferred injection zones and formations. We agree 

with US EPA that such flexibility may greatly increase the opportunities for 

significant, safe sequestration in states such as ours, where potential USDWs 

may exist at depths in excess of 15,000 below surface. In those situations few, 

if any, opportunities exist for GS beneath deep USDWs, given the absence of 

geologic conditions (i.e. porosity, permeability, thickness) favorable to 

injection. Furthermore, we believe that GS can be performed safely and 

successfully in shallower geologic environments while also being protective of 

USDWs, as evidenced by the existence of pressurized natural gas and petroleumbearing deposits above, as well as adjacent to USDWs in Wyoming. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

304
projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA acknowledges that technologies exist to address the challenges associated with GS and injection 

that will be conducted under the waiver approach, e.g., to inject through over-pressured formations. 

However, EPA also believes that additional considerations are necessary when permitting such wells to 

ensure protection of all USDWs and that the additional requirements that apply to owners or operators 

of Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide this 

protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Chris Korleski 

Commenter Organization: Ohio Environmental Protection Agency (Ohio EPA) 

EPA Letter ID: 0390 

EPA Comment ID: 28309 

Comment: Ohio EPA is supportive of US EPA's proposal to create a waiver process to allow 

on a case by case basis the injection of CO2 above an underground source of 

drinking water. Ohio EPA agrees with the waiver process as described within the 

notice of data availability and request of comments. Ohio EPA agrees that the 

request for a waiver should include: site specific geologic and hydrogeologic 

information; be reviewed in consultation with the Drinking Water Program; and be 

optional for adoption by state programs with primacy. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

305
injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs.

EPA clarifies that the information requirements to support waiver applications as specified in 

§146.95(a) include the types of site-specific geologic and hydrogeologic information the commenter 

suggests. In addition, §146.95(b) requires consultation with the PWSS Director. EPA adds that 

adoption of the waiver process will remain at the discretion of individual UIC programs. Therefore, 

States, Territories, and Tribes seeking primacy for Class VI wells are not required to provide for 

injection depth waivers in their UIC regulations and may choose not to make this process available to 

Class VI wells under their jurisdiction. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text that is later repeated in lines 35 to 38. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28321 

Comment: Regarding EPA's Notice of Data Availability, API is supportive of EPA's effort 

to introduce flexibility on the depth of injection relative to location of USDWs 

by proposing a waiver process. API holds that CO2 can be injected above a USDW 

while protecting the USDW and maintaining access to the USDW for future use. As 

noted in last year's testimony, the Salt Creek EOR project in Wyoming which has 

a USDW below the injection zone is an excellent example of how industry can 

operate CO2 injection wells in an EOR context without endangering or limiting 

access to USDWs that are located below the injection zone. 

Accessing USDWs below a CCS site, while not trivial, does not present 

significant technological hurdles. Industry has the technology to drill through 

over-pressured gas reservoirs which are analogous to CCS sites. There are some 

excellent offshore technologies for drilling through salt formations and shallow 

306
gas pockets that involve the same type of pressure issues that would be 

encountered in drilling through a CCS site. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs. 

EPA agrees with the commenter that technologies exist to address the challenges associated with GS 

and injection that will be conducted under the waiver approach, e.g., to inject through overpressurized reservoirs. However, EPA also believes that additional considerations are necessary when 

permitting such wells to ensure protection of all USDWs and that the additional requirements that 

apply to owners or operators of Class VI wells granted a waiver of the injection depth requirements at 

§146.95 will provide this protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28327 

Comment: In conclusion, API is supportive of the waiver approach for dealing with 

injection above the lowermost USDW. API is still concerned, though, that by 

307
Individual Response: As described above, EPA acknowledges the commenter's support of the waiver 

approach and site-specific flexibility in regulatory development and permitting as described in the 

NODA and Request for Comment. The Agency acknowledges that there are some situations where 

injection into non-USDW formations above the lowermost USDW can be performed in a manner that 

protects USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3220 3.2.2. Comments in Opposition to the Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27925 

Comment: d. At page 47 FR 44809, EPA discusses "injecting above the USDW". 

Many Underground Sources of drinking Water (USDW) are located in contact 

with the vados zone, which is open to the atmosphere. Injecting CO2 above the 

USDW could allow CO2 to return to the atmosphere. Those USDW’s not associated 

with a vados zone would be so close to the surface that injecting at ± 2200 psi 

would likely destroy the geological seal and blowout would occur. Injecting 

above the USDW appears to court disaster. 

Individual Response: EPA clarifies that no injection will be allowed into any formation that does not 

have a confining layer that is capable of containing CO2 injected at the proposed injection pressure 

308
without fracturing. EPA also clarifies that the target formations anticipated for GS, including those 

projects operating under a waiver, will be hundreds of feet deep and not "open to the atmosphere" as 

the commenter suggests. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Anonymous9 

Commenter Organization: 

EPA Letter ID: 0335 

EPA Comment ID: 28214 

Comment: invested in renewables and efficiency instead. But to allow injection above the 

lowest underground source of drinking water is INSANE, why would anyone in 

his/her right mind think that's an acceptable thing to do? For crying out loud, 

DON'T ALLOW THIS!!!!!!!!!!!! 

Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the 

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that 

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is 

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees 

that finalization of the GS rule is premature. For additional information regarding the data on which 

EPA based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on 

the proposed injection depth requirements and the waiver process discussed in the NODA, and 

concerns about USDW protection, EPA believes that there are situations where injection into nonUSDW formations above the lowermost USDW can be performed in a manner that protects USDWs. 

The final GS rule at §146.95 establishes a process by which owners or operators can seek a waiver of 

the Class VI injection depth requirements. The waiver approach establishes requirements for extensive 

site-specific information related to injecting above or between USDWs that the owner or operator must 

submit and the Director must consider, in consultation with PWSS Directors, to ensure that water 

supplies in the area and all USDWs are protected. 

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include: modified construction requirements and requirements to 

309
monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 29036 

Comment: resources while promoting reduction of greenhouse gas emissions. The American 

Public Power Association (APPA), a member of CURC, does not agree with comments 

made in this submittal supporting the granting of waiver authority to state UIC 

program directors as more fully explained herein. Therefore APPA cannot support 

these comments. 

Individual Response: EPA acknowledges the commenter's concerns and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on 

the proposed injection depth requirements and the waiver process discussed in the NODA, and 

concerns about USDW protection, EPA believes that there are limited situations where injection into 

non-USDW formations above the lowermost USDW can be performed in a manner that protects 

USDWs. The final GS rule at §146.95 establishes a process by which owners or operators can seek a 

waiver of the Class VI injection depth requirements. The waiver approach establishes requirements for 

extensive site-specific information related to injecting above or between USDWs (including ground 

water use and water supply needs, as the commenter suggests) that the owner or operator must 

submit and the Director must consider, in consultation with PWSS Directors, to ensure that water 

supplies in the area and all USDWs are protected. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

310
EPA Letter ID: 0339 

EPA Comment ID: 28010 

Other EPA Comment Codes and Descriptions: 3100 3.1. Comments on Concerns About Injection 

Depth for Class VI Wells 

Comment: B. SWRCB Comment #2 on: "IV. Injection Depth for GS Projects A. What did EPA 

propose for Class VI well injection depth relative to the location of USDWs?" 

Injecting CO2 above or below the water supply aquifer is irrelevant since under 

extreme pressure and high temperature, CO2 gas will migrate downward and upward, 

following porosity, fault zones or man-made pathways. Plus, you cannot compare 

CO2 gas to liquid injection since CO2 gas will expand under pressure in all 

directions, and has much greater mobility than fluids. Gas will penetrate rock 

with much smaller opening pores or fractures than those needed for fluid 

migration. Fluid compressibility and subsequent expansibility is negligible 

compared to this of gases. The LBNL modeling showed injected gas will expand for 

hundreds of miles, for many years after injection stops, and sooner or later may 

reach area(s) where will be able to escape to the surface or drinking water 

aquifer. 

CO2 is heavier than air and if release to the surface at high concentration will 

be deadly. 

Individual Response: EPA believes proper siting, well construction, operation, monitoring, and postinjection site care will allow CO2 to be sequestered, despite its buoyancy. The GS rule is designed to 

ensure that appropriate requirements are in place to protect USDWs from endangerment. EPA 

acknowledges that faults and artificial penetrations offer paths for fluid movement. For this reason, 

the GS rule contains requirements at §146.82 for characterization of faults and fractures, and §146.84 

requires an AoR evaluation and corrective action. For additional information on characterization of 

faults and fractures, AoR, and corrective actions, see the preamble to the final rule and the responses 

to comments on the proposed GS rule. 

In addition, owners or operators seeking waivers from the injection depth requirements must provide 

additional information about the injection zone; identification of confining units above and below the 

injection zone; and tailored AoR modeling above and below the injection zone, as required at 

§146.95(a). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

311
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

EPA Letter ID: 0339 

EPA Comment ID: 29236 

Comment: No waiver should be issued in any area that has extensive groundwater use, high 

density water or oil wells, seismically unstable now or potentially in the 

future, potential for earthquakes, volcanic activities presently or in distant 

future. 

Injecting such a small fraction of CO2 is high risk and its cost to benefiteffect on climate change is negligible. Also, the State of California does not 

allow for permits to dispose of hazardous materials through injection wells. 

Individual Response: EPA acknowledges the commenter's concerns about USDW protection and 

clarifies that the mission of the UIC Program is to protect USDWs from endangerment. Based on an 

evaluation of comments on the proposed injection depth requirements and the waiver process 

discussed in the NODA, and concerns about USDW protection, EPA believes that there are limited 

situations where injection into non-USDW formations above the lowermost USDW can be performed in 

a manner that protects USDWs. The final GS rule at §146.95 establishes a process by which owners or 

operators can seek a waiver of the Class VI injection depth requirements. The waiver approach 

establishes requirements for extensive site-specific information related to injecting above or between 

USDWs (including ground water use and water supply needs, as the commenter suggests) that the 

owner or operator must submit and the Director must consider, in consultation with PWSS Directors, 

to ensure that water supplies in the area and all USDWs are protected. 

EPA clarifies that any decision to grant a waiver (or a Class VI permit) will be based on extensive 

study of the proposed area, including the number and condition of wells in the air and seismic history.

EPA Team Member: 

Draft Status: 

Date Uploaded: 18-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: William E. Freeman 

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Commenter Organization: Navajo Nation 

EPA Letter ID: 0341 

EPA Comment ID: 28024 

Comment: Comment: 

Due to the mobility and corrosive nature of CO2, sequestration 

should be below the lowest USDW. Not all geologic provinces in the U.S. are 

suitable for CO2 sequestration. 

Individual Response: EPA agrees that not all regions are suitable for GS. However, based on an 

evaluation of comments on the proposed injection depth requirements and the waiver process 

discussed in the NODA, and concerns about USDW protection, EPA believes that there are situations 

where injection into non-USDW formations above the lowermost USDW can be performed in a manner 

that protects USDWs. The final GS rule at §146.95 establishes a process by which owners or operators 

can seek a waiver of the Class VI injection depth requirements. The waiver approach establishes 

requirements for extensive site-specific information related to injecting above or between USDWs that 

the owner or operator must submit and the Director must consider, in consultation with PWSS 

Directors, to ensure that water supplies in the area and all USDWs are protected. Such decisions will 

be made on a case by case basis after reviewing the required data, including proof of continuous 

confining layers above and below the proposed injection zone and proof that the injection zone 

formation does not outcrop. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Emily Rochon 

Commenter Organization: Greenpeace International 

EPA Letter ID: 0342 

EPA Comment ID: 28030 

Comment: Injection depth for GS Projects should remain as originally proposed in draft 

rule 

Greenpeace supports the EPA's original proposal to constrain injection to 

below the lowermost USDW. Maximizing protection of UDW is the priority of the 

SDWA and this standard should not be relaxed in order to facilitate underground 

storage of CO2. As noted by Dr. Sally Benson, "The biggest risk of storage and 

saline aquifers is potential impacts to ground water." [Footnote 2] 

313
[Footnote 2]: Sally M. Benson. Carbon Capture and Sequestration: Technological 

Challenges. (A University of California, Berkeley, symposium) Video presentation 

by Sally M. Benson, Executive Director, The Global Climate and Energy Project, 

Stanford University. November 13, 2008. See: 

http://video.google.com/videoplay?docid=665563992926487780&hl=en 

In Florida, partially treated wastewater has been injected into saline 

formations underground for more than 30 years. Over time, some of that 

contaminated water has migrated into UDW.[Footnote 3] The analogy to CO2 storage 

is inescapable. It is foolish to assume that all of the stored CO2 will stay in 

its place and not migrate into UDW sources. Leakages of CO2 will undoubtedly 

occur because things such as poor planning, unforeseen complications and bad 

project management cannot be ruled out. 

[Footnote 3]: David. W. Keith, et al. "Regulating the Underground Injection of 

CO2: Florida's battle over injecting wastewater deep underground offer a lesson 

for any future U.S. regulation of the underground disposal and sequestration of 

CO2". Environmental Science and Technology. December 15, 2005. 

In the context of the SDWA, the question before the EPA is not how best to 

facilitate the storage of CO2 but how best to prevent protect UDW. From 

Greenpeace's perspective, that means not allowing any injection to occur above 

USDWs. 

We are aware that such a requirement could preclude the use of CO2 storage in 

certain parts of the country but it is worth noting that CO2 storage is not a 

necessity, it is merely a potential option that could stem the increase in 

atmospheric concentrations of global warming pollution. Places where CO2 

storage would be ruled out by such a requirement can explore alternative 

measures to combat climate change and meet their energy needs. For example, a 

variety of untapped renewable energy resources are available throughout the 

United States and can be readily harnessed with existing technologies. Western 

states, in particular, have tremendous renewable energy potential and western 

Governors are increasingly committed to diversifying their energy sources, which 

means less coal and CO2.[Footnote 4] Energy efficiency measures are also available to 

reduce the growth of energy demand. Both of these options avoid the generation 

of new CO2 and obviate the need for underground storage. 

[Footnote 4]: See Western Governors' Association Policy resolution on renewable energy: 

http://www.westgov.org/wga/policy/09/energy.pdf 

314
Conclusion 

Given the substantial knowledge gaps relating to our ability to 

execute carbon storage safely, Greenpeace argues that the permitting and 

regulation of large scale geological storage projects is premature. Given the 

fact that technical feasibility of CCS is not expected until 2030, it would seem 

prudent to wait for proof that environmentally sound carbon storage is possible 

before moving forward with regulations. The inability of the EPA to fully 

address the issue of CO2 storage under the SDWA underscores is another critical 

reason for the Agency to hold off on promulgating final regulations at this 

juncture. 

In considering the new science on the GS storage of CO2, we hope that the EPA 

recognizes the need to proceed with the utmost caution on this issue. Keeping 

in mind its mandate to maximize the protection of UDW, it should not weaken any 

standards that facilitate CO2 storage operations at the expense of that mandate. 

Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the 

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that 

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is 

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees 

that finalization of the GS rule is premature. For additional information regarding the data on which 

EPA based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on 

the proposed injection depth requirements, the waiver process discussed in the NODA and Request for 

Comment, and concerns about USDW protection, EPA believes that there are situations where 

injection into non-USDW formations above the lowermost USDW can be performed in a manner that 

protects USDWs. The final GS rule at §146.95 establishes a process by which owners or operators can 

seek a waiver of the Class VI injection depth requirements. 

The waiver approach establishes requirements for extensive site-specific information related to 

injecting above or between USDWs that the owner or operator must submit and the Director must 

consider, in consultation with PWSS Directors, to ensure that water supplies in the area and all USDWs 

are protected. Furthermore, owners or operators granted injection depth waivers are subject to 

additional requirements at §146.95(f), which include: modified construction requirements and 

requirements to monitor above and below the injection zone in order to ensure protection of USDWs 

underlying and overlying the injection zone during both well operation and the post-injection site care 

period. 

315
In response to the comment regarding unintended consequences related to municipal disposal wells in 

Florida, EPA clarifies that GS is different from the injection of wastewater in Florida. An owner or 

operator seeking to characterize a site for GS pursuant to the requirements at §146.82 and identify 

both injection formations and suitable confining units per §146.83 may not be able to meet the 

requirements and ensure protection of USDWs due to the nature of karst formations/geology. In 

addition, the computational modeling required to delineate the AoR for a GS project would likely 

predict inappropriate buoyant flow and eliminate such formations as potential GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27911 

Comment: Injection Depth for GS Projects (IV) 

We believe GS should only be allowed beneath the lowest Underground Source of 

Drinking Water (USDW). Protecting USDW is the most important aspect of the UIC 

program and of great importance for the regional state economy and 

sustainability. Verifiable containment or a cap rock is critical to prevent the 

migration of CO2 upward into USDWs. Allowing the EPA Director or states with 

delegated UIC programs to require additional confining zones is important to 

protect USDWs, especially in geologically marginal areas where GS may occur. 

Waiver Process (IV.D.) 

EPA is considering an alternative through a waiver process to allow GS injection 

above and between USDWs under specific conditions that would provide 

flexibility and allow for more site- specific assessment. We do not support the 

waiver process allowing injection above and between USDWs and alternatives that 

will undermine long term protection of USDWs for the following reasons: 

- The waiver process is a divergence from Class I and III requirements and would 

allow for modifications and widespread use. 

316
- GS in Oregon could be proposed in Columbia River Flood basalts not in saline 

basins, or deep buried volcanic plains. Oregon currently has no exempt aquifers 

- all aquifers statewide under the 1990 State Groundwater Act are considered to 

be protected and potable. 

- The waiver would place a greater burden on the state to administer this 

program that is minimally supported by current EPA funding levels that are 

directed towards Class I and II development. 

Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the 

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that 

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is 

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees 

that finalization of the GS rule is premature. For additional information regarding the data on which 

EPA based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on 

the proposed injection depth requirements, the waiver process discussed in the NODA and Request for 

Comment, and concerns about USDW protection, EPA believes that there are situations where 

injection into non-USDW formations above the lowermost USDW can be performed in a manner that 

protects USDWs. The final GS rule at §146.95 establishes a process by which owners or operators can 

seek a waiver of the Class VI injection depth requirements. The waiver approach establishes 

requirements for extensive site-specific information related to injecting above or between USDWs that 

the owner or operator must submit and the Director must consider, in consultation with PWSS 

Directors, to ensure that water supplies in the area and all USDWs are protected. 

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include modified construction requirements and requirements to 

monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA clarifies that adoption of the waiver process remains at the discretion of individual UIC programs. 

Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are not required to 

provide for injection depth waivers in their UIC regulations and may choose not to make this process 

available to Class VI wells under their jurisdiction. This approach allows flexibility for individual 

program Directors to determine the appropriateness of allowing for waivers based on regional or 

state-specific conditions, such as the predominant geologic settings anticipated to be used for GS or 

other land uses in the state while ensuring maximum protection of USDWs. The final approach for 

injection depth waivers represents minimum Federal requirements. UIC program Directors may adopt 

317
GS requirements that do not allow injection above or between USDWs if they determine this to be 

appropriate (for conditions in their State, territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27936 

Comment: AWWA would also like to reiterate our concern of the current classification of a 

USDW as the best sources of drinking water are already being used by utilities. 

With the potential impacts from climate change, drinking water utilities are 

facing an even more limited supply of fresh drinking water. As a result, many 

utilities are turning to more challenging groundwater sources such as those that 

are very deep or have high salinity concentrations. Some of these new sources 

could fall outside of the current definition of a USDW, in that the aquifer has 

a TDS concentration higher than 10,000 ppm. The definition of a USDW was 

written at a time when many advanced water treatment technologies were generally 

cost prohibitive, and the general thinking that the high-salinity aquifers would 

never be utilized as drinking water sources. 

Recognizing that it is difficult to extend protection to these aquifers due to 

the restrictions of the SDWA, AWWA recommends that during the project planning 

process or the injection depth waiver process (as identified in this NODA), the 

owner/operators should include state environmental departments as they can 

provide insight into what aquifers not currently classified as USDWs might be 

considered as future drinking water sources. The stakeholder process should 

also involve both regional and local planning boards, as well as the local water 

utilities. This process will allow for protection to be extended to the nontraditional aquifers, which will be necessary given the pressures on water 

resources that the country will be facing in the upcoming century. In addition, 

this process will prevent waivers from being issued for injection into saline 

aquifers that could be considered as future sources of drinking water. 

318
Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the 

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that 

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is 

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees 

that finalization of the GS rule is premature. For additional information regarding the data on which 

EPA based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. The final GS rule includes a requirement at 

§146.95(b)(2) that the UIC Program Director consult with the PWSS Directors of all States, Territories, 

and Tribes having jurisdiction within the AoR of a well for which a waiver is sought. EPA believes this 

process is necessary and appropriate to ensure that water system concerns are considered when 

evaluating a waiver application. EPA requires this information be documented to ensure that this 

consultation will enable transparent public disclosure of all information evaluated by the Directors and 

their respective recommendations.

EPA agrees that a stakeholder process that includes environmental departments, regional and local 

planning boards, and local water utilities is important. EPA has added a requirement at 

§124.10(c)(1)(xi) that state and local oil and gas regulatory agencies and state agencies regulating 

mineral exploration and recovery, the PWSS program director, and all agencies that oversee injection 

wells in the state must be notified as part of the public notice process for a Class VI permit. For 

additional information on public participation associated with GS projects, see the preamble to the 

final rule and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27940 

Comment: WAIVER PROCESS FOR INJECTION ABOVE AND/OR BETWEEN USDWs 

AWWA is in strong opposition to the proposed waiver process for injection above 

and/or between USDWs as it presents too great a risk to USDWs. GS is still an 

emerging technology and EPA should employ caution at this time until more 

experience is gained with pilot studies of deep saline injection zones. Efforts 

319
to date have focused on containment of supercritical carbon dioxide rather than 

gaseous or liquid forms that might exist at shallower depths. It is unclear how 

owners/operators would be able to demonstrate containment of these plumes. 

Further research is necessary to define suitable management practices. 

AWWA is concerned that a waiver process, as well as the proposed regulation, has 

many limitations that could allow for the degradation of USDWs. Many of the 

requirements are based on faith and not data, and the drinking water community 

and the citizens they serve are being asked to trust that geologic sequestration 

technology will work even though there is very little experience with this 

technology at a large scale. For example, the requirements for determining the 

direction of carbon dioxide plume migration, predicting confining layer 

containment potential, and identifying necessary geo-chemical monitoring are 

based on modeling exercises, with limited monitoring data to validate these 

models and limited real-life data to support the requirements. The possibility 

for unintended consequences to occur with geologic sequestration is very real 

and is similar to what was observed with the use of MTBE. MTBE is the fuel 

additive that was meant to solve an air pollution problem but its use resulted 

in unanticipated drinking water pollution problems. Carbon dioxide is an energy 

production/use byproduct that causes air pollution/climate problem but whose 

mitigation (using geologic sequestration) could cause drinking water 

contamination and other (supply) problems. EPA needs to draw on the lessons 

learned from the MTBE situation, and do everything possible to prevent a similar 

situation from occurring with geologic sequestration. Even though MTBE is an 

excellent example, the difference in scale between the possible unintended 

consequences of sequestration and MTBE are huge. Experience gained from deep 

injection wastewater wells in Florida should also be documented and considered. 

AWWA strongly recommends that EPA not move forward with the injection depth 

waiver process. If EPA decides to proceed down this road despite AWWA’s 

negative comments, there are several significant issues that EPA needs to 

consider: 

- EPA’s suggested criteria for approving a GS injection depth waiver includes a 

requirement that the owner/operator identify all artificial penetrations in the 

Area of Review that penetrate the injection zone, the upper and lower confining 

zones, and all USDWs in the area. The stated purpose of this demonstration would 

be to ensure that public water supplies, private wells, and potential future 

water resources are identified and the location of artificial penetrations into 

such formations are known and these artificial penetrations can be appropriately 

plugged during the permitting process. Because drinking water wells are 

320
artificial penetrations, it appears that they would be plugged, making them 

useless for supplying water. If not, it is unclear how the owner/operator can 

demonstrate that the construction of these wells is equivalent to Class VI well 

requirements and thus would not serve as conduits to contaminate USDWs. 

- It is unclear that technology has been developed for drilling through 

injection zones containing stored carbon dioxide without releasing some of the 

stored gas. EPA should insist that demonstration of such technologies be 

performed before considering a waiver program. 

-The risk of damaging water or mineral resources will be greatly increased, and 

there needs to be an adequate mechanism for compensating water utilities and 

other resource owners for remedial actions that must be taken to restore or 

replace beneficial uses. 

Individual Response: EPA agrees that USDW protection is the highest priority; the purpose of the 

GS regulation is to ensure that GS, where deployed, is conducted in a manner that protects USDWs.

EPA clarifies that the mission of the UIC Program is to protect USDWs from endangerment. Based on 

an evaluation of comments on the proposed injection depth requirements and the waiver process, EPA 

believes that there are limited situations where injection into deep non-USDW formations above the 

lowermost USDW can be performed in a manner that protects USDWs. The final GS rule at §146.95 

establishes a process by which owners or operators can seek a waiver of the Class VI injection depth 

requirements. The rule establishes requirements for extensive site-specific information that the owner 

or operator must submit and the Director must consider, in consultation with PWSS Directors, to 

ensure that all USDWs are protected. This information includes a modified AoR evaluation that 

addresses the need for confinement above and below the injection formation, the additional impacts of 

artificial penetrations, and the location of all the public water supplies affected, reasonably likely to be 

affected, or served by USDWs in the AoR. The Agency anticipates that injection depth waivers will be 

issued in limited circumstances.

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), including modified construction requirements and requirements to 

monitor above and below the injection zone to ensure protection of USDWs underlying and overlying 

the injection zone during both well operation and the post-injection site care period. EPA adds that, for 

GS projects where injection depth waivers are sought, the Director must also consider the proposed 

emergency and remedial response plan and a demonstration of financial responsibility in making a 

determination whether to grant a waiver §146.95(b)(1)(iv).

In an effort to ensure national consistency and application of the requirements, §146.95(d) requires 

321
the Regional Administrator to make the final determination regarding waiver issuance following an 

evaluation of all site-specific information, public notice, and recommendations from the UIC Director. 

EPA believes that UIC Program staff are in the appropriate position to evaluate the technical details of 

the waiver application, in concert with the UIC permit application, to inform the Regional 

Administrator's decision.

EPA disagrees that finalization of the GS rule is premature or is not based on data. EPA believes that 

the tailored requirements for GS wells, which are built on a long-protective UIC regulatory framework 

and extensive data gathered from DOE pilot projects, international full-scale GS projects, and decades 

of Class II ER experience, provide appropriate USDW protection. The Agency believes that a proactive 

approach is appropriate to ensure USDW protection from endangerment.

EPA notes that technologies exist to inject through over-pressured formations while maintaining zonal 

isolation (e.g., oil and gas industry experience in drilling through shallow pockets of gas or other zones 

that have higher pressures). EPA has reviewed information on these types of projects and has 

determined that, if properly constructed, wells can be drilled through pressurized zones without 

causing fluid movement. However, to provide additional USDW protection and ensure that any planned 

drilling is conducted appropriately, the final GS rule requires the Director to consider planned or

permitted water, hydrocarbon, or mineral resource exploitation potential of the proposed injection 

formation and other formations both above and below the injection zone as specified in 

§146.95(b)(1)(vii).

For additional information regarding the data on which EPA based the final GS rule and the specific 

rule requirements, see the preamble to the final GS rule and technical support documents in the 

docket for this rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text that is later repeated in lines 265 to 276 and lines 278 to 286. 

Part of this comment appears three times in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27946 

Comment: Most importantly, AWWA stands by our previously stated positions that injection 

should only be carried out at the pilot phase and only allowed below USDWs. If 

USDW water quality is degraded by a GS project, the owner/operator of that 

322
project is responsible for any costs borne by drinking water utilities due to 

increased treatment requirements for that ground water or replacement of lost 

capacity in perpetuity. The key words are "in perpetuity and without limit", as 

remediation of that contaminated groundwater would continue in perpetuity. 

Individual Response: EPA acknowledges the commenter's concerns about the permanence of 

contamination and the need to protect USDW from endangerment, and clarifies that the mission of the 

UIC Program is to protect USDWs from endangerment. EPA clarifies that owners or operators of all GS 

projects, regardless of whether they are operating under a waiver, must employ proper site 

characterization, construction, operation, testing, monitoring, and post injection site care to ensure 

that USDWs are protected. Owners or operators must also develop an emergency and remedial 

response plan pursuant to the requirements at §146.94 to address potential USDW contamination and 

demonstrate financial responsibility, as required at §146.85 as part of the permit application process. 

The purpose of the emergency and remedial response plan and associated financial responsibility 

requirements is to explain that an owner or operator has considered regional water resource issues, 

has explored alternative water supplies or water treatment options to address unanticipated 

movement of the injectate or formation fluids into any overlying or underlying USDWs, and has 

appropriate resources to address the need for future response actions to protect USDWs from 

endangerment. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 28578 

Comment: Despite providing the above-mentioned requirements, it is important to note that 

AWWA remains in strong opposition to the injection depth waiver process and our 

suggestion of these requirements in no way means that AWWA endorses the 

injection depth waiver process. However, we recognize that if EPA does decide to 

move forward on this issue, providing comment in response to the waiver question 

in the NODA is our only opportunity to shape the final regulation for GS using 

Class VI injection wells. 

323
Individual Response: EPA acknowledges the commenter's concerns about USDW protection and, as 

described above, clarifies that the mission of the UIC Program is to protect USDWs from 

endangerment. EPA believes that there are situations where injection into non-USDW formations 

above the lowermost USDW can be performed in a manner that protects USDWs. 

The waiver approach at §146.95 establishes requirements for extensive site-specific information 

related to injecting above or between USDWs that the owner or operator must submit and the Director 

must consider, in consultation with PWSS Directors, to ensure that water supplies in the area and all 

USDWs are protected. 

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include: modified construction requirements and requirements to 

monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert S. Lynch 

Commenter Organization: Irrigation & Electrical Districts Association of Arizona 

EPA Letter ID: 0372 

EPA Comment ID: 27949 

Comment: We are particularly concerned about the language the notice uses on page 44811 

concerning the proposed waiver that would allow drilling to and storage between 

Underground Sources of Drinking Water (USDW). 

We think it goes without saying that any new and relatively untested scheme for 

underground storage of CO2 and other greenhouse gases by use of injection wells 

is fraught with potential problems. EPA must agree because it has proposed 

requirements for emergency and remedial response and financial responsibility. 

These are obviously important elements in any waiver process that the agency 

would implement. What concerns us, however, is the vague language discussing 

these critical subjects. 

Individual Response: EPA acknowledges the commenter's concerns about USDW protection and 

clarifies that the mission of the UIC Program is to protect USDWs from endangerment. Based on an 

324
evaluation of comments on the proposed injection depth requirements and the waiver process 

discussed in the NODA and Request for Comment, and concerns about USDW protection, EPA believes 

that there are situations where injection into non-USDW formations above the lowermost USDW can 

be performed in a manner that protects USDWs. The final GS rule at §146.95 establishes a process 

and specific requirements by which owners or operators can seek a waiver of the Class VI injection 

depth requirements. The waiver approach establishes requirements for extensive site-specific 

information related to injecting above or between USDWs that the owner or operator must submit and 

the Director must consider, in consultation with PWSS Directors, to ensure that water supplies in the 

area and all USDWs are protected. 

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include: modified construction requirements and requirements to 

monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA clarifies that the purpose of the emergency and remedial response requirements is to address the 

remote possibility for USDW contamination associated with GS wells. EPA stresses that the primary 

focus of USDW protection in the GS rule is proper site characterization, construction, operation, 

testing, monitoring, and post-injection site care of all GS projects.

EPA disagrees that finalization of the GS rule is premature or the technology is untested. EPA believes 

that the tailored requirements for GS wells, which are built on a long-protective UIC regulatory 

framework and extensive data gathered from DOE pilot projects, international full-scale GS projects, 

and decades of Class II ER experience, provide adequate USDW protection. For additional information 

regarding the data on which EPA based the final GS rule, see the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert S. Lynch 

Commenter Organization: Irrigation & Electrical Districts Association of Arizona 

EPA Letter ID: 0372 

EPA Comment ID: 27951 

Comment: In short, we believe that the safety net alluded to in this Federal Register 

notice lacks so much detail as to be too imprecise a basis on which to make a 

decision about whether to institute the waiver process or not. Protecting the 

quality of our ground water resources in the desert is a matter of utmost 

325
concern. We think EPA ought to go back to the drawing board on this one until 

it can articulate with some specificity the safety net it will require for 

anyone seeking to implement this waiver process. 

Individual Response: The final GS rule, at §146.95(a), requires owners or operators to submit 

information to support a determination regarding whether a waiver from the injection depth 

requirements should be granted. The rule requires that the owner or operator provide:

• A demonstration that the injection zone is laterally continuous, not connected to a USDW, does not 

outcrop, and can safely contain the proposed amount of CO2 injection.

• A demonstration that adequate confining layers are present above and below the injection zone.

• A demonstration using modeling that USDWs will not be endangered by fluid movement.

• A demonstration that well construction will isolate the injection zone from other zones.

• The location of all water supplies in the area that may be affected by the injection.

• A description of planned monitoring above and below the injection zone.

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include: modified construction requirements and requirements to 

monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: B. Peter McGrail 

Commenter Organization: Pacific Northwest National Laboratory 

EPA Letter ID: 0375 

EPA Comment ID: 28160 

Comment: We applaud the EPA for listening to criticisms from knowledgeable scientists and 

engineers regarding the unwarranted and technically indefensible position 

326
prohibiting CO2 injection above and between USDWs, which the EPA issued in its 

original July 25, 2008, proposed rule, "Federal Requirements Under the 

Underground Injection Control (UIC) Program for Carbon Dioxide (CO2) Geologic 

Sequestration (GS) Wells". Furthermore, we strongly concur with the core 

principle articulated in this NODA that all geologic formations receive equal 

treatment and the rule should allow specific regions of the country the 

regulatory flexibility to determine if any injection at a particular site and 

depth is the appropriate approach. Unfortunately, the proposed waiver process 

and specifically the extraordinary set of additional technical and financial 

requirements imposed through the waiver process clearly violate these principles 

by establishing a set of virtually insurmountable barriers for any 

owner/operator seeking a UIC permit for a GS project through the waiver process. 

The EPA has cited no technical evidence to suggest elevated risk factors from 

properly sited GS projects conducted above or between USDWs that would justify 

imposition of the additional site characterization, emergency response planning, 

financial liability, alternative water resource planning, and the many other 

additional requirements outlined in this draft NODA. We strongly urge the EPA to 

draft a single and consistent set of requirements that all GS sequestration 

projects must meet to ensure site suitability. 

Individual Response: EPA believes there is potential risk associated with injection into non-USDW 

formations above the lowermost USDW and additional requirements are warranted. For example, 

there is a risk of downward migration of fluids if there is no lower confining layer or inadequate 

confinement. In addition, there is the potential that wells will be drilled through the injection zone in 

the future to reach the USDW. EPA believes that the additional requirements that apply to owners or 

operators of Class VI wells granted a waiver of the injection depth requirements at §146.95 will 

provide additional information when permitting such wells to ensure protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28104 

327
Comment: With such limited information and significant potential adverse consequences, 

the proposal for a waiver process to allow for GS injection above and between 

USDWs is premature. AMWA recommends that EPA not proceed with a waiver process 

at this time. Instead, the agency should commit to wait for the data from pilot 

projects relevant to interactions between groundwater and the injected CO2 prior 

to considering the implementation of any waiver process. We reiterate our 

December 23, 2008 comments and urge EPA to "prohibit the construction of CO2 

sequestration wells in aquifers currently used for drinking water supply or 

expected to be used in the future." 

Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the 

purpose of the GS regulation is to ensure that GS, where deployed, is conducted in a manner that 

protects USDWs. Incentivizing the use of GS or other renewable energy resources and technologies is 

outside the scope of this rulemaking and the UIC Program’s authority under the SDWA. EPA disagrees 

that finalization of the GS rule is premature. For additional information regarding the data on which 

EPA based the final GS rule, see the preamble to the final GS rule.

EPA acknowledges the commenter's concerns about USDW protection and clarifies that the mission of 

the UIC Program is to protect USDWs from endangerment. Based on an evaluation of comments on 

the proposed injection depth requirements and the waiver process discussed in the NODA and Request 

for Comment, and concerns about USDW protection, EPA believes that there are situations where 

injection into non-USDW formations above the lowermost USDW can be performed in a manner that 

protects USDWs. The final GS rule at §146.95 establishes a process by which owners or operators can 

seek a waiver of the Class VI injection depth requirements. The waiver approach establishes 

requirements for extensive site-specific information related to injecting above or between USDWs that 

the owner or operator must submit and the Director must consider, in consultation with PWSS 

Directors, to ensure that water supplies in the area and all USDWs are protected. 

Furthermore, owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f), which include: modified construction requirements and requirements to 

monitor above and below the injection zone in order to ensure protection of USDWs underlying and 

overlying the injection zone during both well operation and the post-injection site care period. 

EPA disagrees that adoption of the waiver process is premature. The Agency has collected data on 

various types of injection activities, including Class II injection and current GS activities and from 

commenters, and believes that issuance of waivers pursuant to the additional protective requirements 

at §146.95 (e.g., consideration of water resources issues, consultation with PWSS Directors, and 

additional permit requirements) will allow injection that addresses capacity concerns and protects 

USDWs. 

EPA Team Member: 

328
Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28105 

Comment: AMWA recommends that EPA work with the Department of Energy and other interested 

parties to develop current and future pilot projects to demonstrate the proof of 

concept of a waiver prior to implementing a waiver provision. EPA should 

implement the pilot program with the aim of evaluating GS technology in areas 

where, after careful review, the technology is determined to be the most viable 

alternative for reducing greenhouse gas (GHG) emissions, yet it would be a 

candidate for a waiver because the geologic formation for sequestration is above 

the USDW. AMWA also recommends that the pilot program be set up with the 

purpose of evaluating the technology and gathering as much comprehensive data as 

possible, particularly with regard to water/rock/gas interaction and the impacts 

of injected CO2 on aquifers within the area of review. The NODA provides 

information about preliminary studies by Lawrence Berkley National Labs, and 

notes that the conclusions of these studies also recommended that further 

studies be conducted, including laboratory or field studies. To this end, 

modeling should be carried out in conjunction with the pilots and the model 

results validated by the data gathered from pilot projects; the modeling results 

described in the NODA are not validated and of minimal predictive value. 

In its July 25, 2008 rule proposal for CO2 geosequestration (73 Federal Register 

43492), EPA noted that an adaptive approach to the rulemaking would be required. 

AMWA supported this approach, recommending that EPA "commit to update the rule 

regularly as more becomes known about carbon capture and sequestration (CCS) 

technology and the behavior of CO2 injected into the subsurface." AMWA 

recommends that the first step in the adaptive approach to the waiver process is 

to gather more information from pilot projects currently underway, as well as 

pilot projects from potential waiver scenarios. The following step would be to 

proceed to develop a formal waiver process, only if warranted. 

329
Individual Response: As described above, EPA disagrees that adoption of the waiver process is 

premature, and the Agency clarifies that the GS rule requirements are based on extensive research, 

including the results of DOE pilot projects. 

As part of its adaptive approach to regulating GS, EPA plans, every six years, to collect and review

data on GS projects, including information on any Class VI wells granted a waiver of the injection 

depth requirements, to determine whether the appropriate amount and types of information and 

appropriate documentation are being collected, and to determine if modifications to the requirements 

are appropriate or necessary. Given the unique nature of the waiver of injection depth requirements, 

the Agency will further assess if the requirements provided in §146.95 are appropriately designed to 

evaluate waiver applications, issue waivers, and ensure protection of USDWs. The adaptive approach 

will also afford the Agency an opportunity to assess the manner in which waivers are issued across the 

US. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes:

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28311 

Comment: The first area I want to touch on relates to siting decisions. Originally, the 

proposed Class VI regulations prohibited any injection and storage above the 

lowermost USDW. For a number of reasons, this prohibition was unnecessary, and 

in recognition of this, EPA proposed the waiver program to inject some, no pun 

intended, flexibility into the administration of the program. 

EEI appreciates the efforts the EPA is making to increase flexibility, but we 

believe that the appropriateness of any given receiving formation should be 

considered on a case by case basis in light of the geologic characteristics of a 

given project in clear and appropriate parameters set forth in the rules. A case 

by case approach would provide the same level of protection for USDWs as a 

waiver process which could still create a perception that geologic storage 

projects pose a heightened risk to drinking water. The case by case approach, 

with the creation of clear and appropriate parameters, would also provide more 

transparency and predictability than the waiver process to future applicants. 

330
Individual Response: EPA agrees that all decisions regarding waivers (and all aspects of GS project 

permitting) should be made on a site-specific basis, as the commenter suggests. The waiver approach 

establishes requirements for extensive site-specific information related to injecting above or between 

USDWs that the owner or operator must submit and the Director must consider, in consultation with 

PWSS Directors, to ensure that water supplies in the area and all USDWs are protected. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3230 3.2.3. Comments that Additional Submissions are Needed (seeking 

comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27944 

Comment: If, after reviewing these significant issues, EPA remains committed to further 

developing the waiver process, the following requirements should be mandatory 

for the siting and operation of GS projects that inject CO2 above the lowermost 

USDW: 

1. A GS owner/operator can only apply for the waiver for injection into a 

formation above the lowermost USDW if there is no other option available for 

sequestering CO2. The waiver process should not be available if there are other 

viable formations located below the lowermost USDW. It is not a process for GS 

owner/operators to use to try and reduce project costs by injecting into a 

shallower aquifer. In addition, the GS owner/operator will collect baseline 

331
water quality data for the potentially impacted USDWs to allow for any 

degradation in water quality to be measured from the baseline conditions that 

exist prior to the injection 

of carbon dioxide. 

2. The carbon dioxide injection well shall be located such that a buffer zone is 

provided between the injection activities and any active or planned drinking 

water wells. The buffer zone shall be large enough as to provide for a minimum 

of ten (10) years of travel time for carbon dioxide, as modeled from the point 

of injection to the drinking water well. In the event of a leakage and/or USDW 

contamination event, this will allow for spatial separation that will provide 

the project owner/operator with enough time to appropriately remediate the 

contamination without adverse impact to the drinking water system. 

3. If injection activities result in the leakage of carbon dioxide into a USDW, 

the GS project owner/operator shall immediately notify operators of drinking 

water wells using that USDW to discontinue using the well if it no longer 

produces safe, wholesome, potable water. Notification shall also be provided to 

the appropriate state and local water and/or public health agencies. The GS 

project owner/operator shall immediately provide an alternative safe drinking 

water supply as approved by the appropriate water and/or public health 

agencies. 

4. Injection above the lower-most USDW should only be allowed if the full extent 

of the carbon dioxide plume does not completely cover the lateral extents of the 

lower-most USDW. The GS project, and resulting carbon dioxide plume, should be 

sited in such a way that provides for a minimum of four (4) separate points of 

access (via new drinking water wells) to the USDW without drilling through the 

plume of sequestered CO2 . These four points should be equally spaced around 

the project footprint to allow drinking water utilities unrestricted access to 

those USDWs without worry of leakage of CO2 during well construction. 

Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpose 

of the UIC requirements. The waiver approach establishes extensive site-specific information related 

to injecting above or between USDWs that the owner or operator must submit and the Director must 

consider, in consultation with PWSS Directors, to ensure that water supplies in the area and all USDWs 

are protected. Furthermore, owners or operators granted injection depth waivers are subject to 

additional requirements at §146.95(f) ensuring protection of USDWs above and below an injection 

zone. 

332
Many of these additional requirements specifically address water resources and the types of 

information the commenter suggests. The rule, at §146.95(b) establishes considerations that the UIC 

Director must assess when evaluating a waiver application to ensure that USDW protection, sitespecific drinking water resource issues, and the use and impact of GS technologies are considered and 

documented. Considerations that address water resources include: community needs, demands, and 

supply from drinking water resources; planned needs, potential and/or future use of USDWs and nonUSDWs in the area; planned or permitted water, hydrocarbon, or mineral resource exploitation 

potential of the proposed injection formation and other formations both above and below the injection 

zone to determine if there are any plans to drill through the formation to access resources in or 

beneath the proposed injection zone/formation; and a proposed plan for securing alternative 

resources or treating USDW formation waters in the event of contamination related to the Class VI 

injection activity.

Other aspects of the final approach to waivers also address the commenter's concerns. For example, 

owners or operators seeking a waiver must demonstrate that the injection zone is bounded by laterally 

continuous, impermeable confining units above and below the injection zone adequate to prevent fluid 

movement and pressure buildup outside of the injection zone; and, that the confining units are free of 

transmissive faults and fractures as specified in §146.95(a)(2). Also, in making a determination 

whether to grant a waiver, the Director must consider potential capacity of the geologic formation to 

sequester CO2, accounting for the availability of alternative injection sites as specified in 

§146.95(b)(1)(iii) and all other site characterization data, the proposed emergency and remedial 

response plan, and a demonstration of financial responsibility as specified in §146.95(b)(1)(iv). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28113 

Comment: 4. EPA should consider modifying 40 CFR Part 146.4 to include an additional 

provision for aquifer exemption based on the expected use of a USDW as a CO2 

storage reservoir. However, in adding such a provision we recommend that the 

proposed injection zone still be required to meet the criteria of not 

being reasonably expected to supply a public drinking water source, whether due 

to location, depth, total dissolved solids content or for other technological or 

333
practical reasons. 

Individual Response: EPA believes that there are limited circumstances where aquifer exemptions 

for GS may be warranted. The final rule allows for the expansion of the areal extent of existing aquifer 

exemptions for Class II EOR/EGR wells transitioning to Class VI injection for GS pursuant to 

requirements at §§146.4 and 144.7(d). However, the final rule precludes the issuance of new aquifer 

exemptions for Class VI GS wells; that is, aquifer exemptions will only be granted for projects that are 

transitioning from Class II EOR/EGR wells to Class VI. 

The aquifer exemption requirements in the final rule provide flexibility and afford owners or operators 

an opportunity to assess and select a suitable GS site while also preserving USDWs (i.e., 

formations/aquifers afforded SDWA protection). Class VI owners or operators granted expansions of 

existing Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored 

requirements for GS wells in the final GS rule.

The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 29336 

Comment: 5. Because injection above USDW’s may present additional questions relative to 

movement of CO2 in the subsurface, we believe EPA should consider adding a 

provision for additional regional hydrologic studies when injection above USDW’s 

is proposed. 

334
Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpose 

of the UIC requirements. The waiver approach establishes extensive site-specific geologic and 

hydrogeologic information related to injecting above or between USDWs that the owner or operator 

must submit and the Director must consider, in consultation with PWSS Directors, to ensure that 

water supplies in the area and all USDWs are protected. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 30-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28175 

Comment: For that reason, we continue to assert that if CO2 injection is permitted above 

the lowermost USDW, the regulations allowing such injection must require (in 

addition to the information EPA asserts the Director would consider in 

evaluating a waiver application): [FOOTNOTE 15] 

- confirmation that there are laterally continuous, impermeable confining units 

above and below the injection zone adequate to prevent fluid movement and 

pressure buildup 

- identification of other wells in the area; and 

- monitoring for changes in groundwater chemistry above the upper confining zone 

and below the lower confining zone. 

FOOTNOTE 15 - 74 Fed. Reg. at 44811. 

EPA should also require, in appropriate circumstances, prior to permit issuance, 

completion of regional hydrogeologic studies that are conducted with sufficient 

accuracy to simulate regional hydrologic flows and demonstrate that USDWs would 

not be endangered if injected or formation fluids were to move beyond either the 

higher or the lower confining zone. 

Before finalizing regulatory language on a waiver process to allow injection 

above the lowermost USDW, EPA should investigate and address the potential need 

for protection against water wells, or wells of any other type that may bisect 

335
pressurized GS reservoirs. 

Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpose 

of the UIC requirements. The waiver approach establishes extensive site-specific information related 

to injecting above or between USDWs that the owner or operator must submit and the Director must 

consider, in consultation with PWSS Directors, to ensure that water supplies in the area and all USDWs 

are protected. This includes site-specific geologic and hydrologic data as the commenter suggests, 

including a demonstration that the injection zone is bounded by laterally continuous, impermeable 

confining units above and below it that are adequate to prevent fluid movement and pressure buildup 

outside of the injection zone; and, that the confining units are free of transmissive faults and fractures 

per §146.95(a)(2). The owner or operator must also describe how the monitoring and testing and any 

additional plans will be tailored to the GS project to ensure protection of USDWs above and below the 

injection zone as specified in §146.95(a)(5). 

In making a determination regarding whether to grant a waiver, the Director must also consider the 

suitability of the injection zone, including current or planned artificial penetrations into the injection 

zone or formations below it as specified in §146.95(b)(ii).

Many of these additional requirements specifically address water resources, as the commenter 

suggests. The requirement at §146.95(b) establishes considerations that the UIC Director must assess 

when evaluating a waiver application to ensure that USDW protection, site-specific drinking water 

resource issues, and the use and impact of GS technologies are considered and documented. 

Considerations associated with water resources include: community needs, demands, and supply from 

drinking water resources; planned needs, potential, and/or future use of USDWs and non-USDWs in 

the area; planned or permitted water, hydrocarbon, or mineral resource exploitation potential of the 

proposed injection formation and other formations both above and below the injection zone to 

determine if there are any plans to drill through the formation to access resources in or beneath the 

proposed injection zone/formation; and a proposed plan for securing alternative resources or treating 

USDW formation waters in the event of contamination related to the Class VI injection activity.

EPA adds that owners or operators granted injection depth waivers are subject to additional 

requirements at §146.95(f) ensuring protection of USDWs above and below an injection zone. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

336
Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28106 

Comment: Amwa strongly recommends that epa take these steps before finalizing the waiver 

provision. However, if epa decides to finalize its rule under the uic program 

for co2 gs wells that includes the waiver provision - despite drinking water 

utilities’ grave concerns about unintended consequences to current and future 

supplies - then amwa recommends the following additional conditions and criteria 

be incorporated into such a provision: 

- A waiver application should only be considered if the owner/operator has 

completed a thorough environmental review including demonstrating that the GS 

option has the least environmental impact and there is no other option for 

reducing greenhouse gas emissions. 

- A waiver application must include additional criteria and requirements that 

provide additional safeguards beyond the proposed requirements for Class VI 

wells, such as more comprehensive monitoring plans. 

Waiver applications should only be considered under very specific circumstances. 

EPA’s proposal for a waiver process should describe in detail how an 

owner/operator must demonstrate the necessity for a waiver. Each waiver 

application would be very site specific but should consider additional criteria 

such as pilot scale and modeling data. 

- A waiver application must be subject to local notice and a public hearing, 

particularly where USDWs or potential USDWs (including high TDS aquifers that 

could be considered for future supplies in light of climate change, normal 

population growth or other supply issues) are in the area of review. 

Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpose 

of the UIC requirements. The waiver approach establishes extensive site-specific information related 

to injecting above or between USDWs that the owner or operator must submit and the Director must 

consider, in consultation with PWSS Directors, to ensure that water supplies in the area and all USDWs 

are protected. 

Many of these additional requirements specifically address impacts to drinking water resources. 

§146.95(b) establishes considerations that the UIC Director must assess when evaluating a waiver 

application to ensure that USDW protection, site-specific drinking water resource issues, and the use 

337
and impact of GS technologies are considered and documented. 

Other aspects of the final approach to waivers also address the commenter's concerns. For example, 

owners or operators seeking a waiver must demonstrate that the injection zone is bounded by laterally 

continuous, impermeable confining units above and below the injection zone adequate to prevent fluid 

movement and pressure buildup outside of the injection zone; and, that the confining units are free of 

transmissive faults and fractures as specified in §146.95(a)(2). The owner or operator must also 

demonstrate using computational modeling, that USDWs above and below the injection zone will not 

be endangered as a result of fluid movement as specified in §146.95(a)(3). The owner or operator 

must also describe how the monitoring and testing and any additional plans will be tailored to the GS 

project to ensure protection of USDWs above and below the injection zone as specified in 

§146.95(a)(5). 

EPA agrees that the waiver application must be subject to local notice and a public hearing; 

§146.95(c) requires the Director to give public notice, as part of the permit application process, 

including notice that a waiver application has been submitted. Furthermore, owners or operators 

granted injection depth waivers are subject to additional requirements at §146.95(f) ensuring 

protection of USDWs above and below an injection zone. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit.

EPA adds that the GS rule does not address the availability of other climate change mitigation options; 

rather the GS rule, including the waiver requirements, are designed to ensure that where deployed, 

GS is performed in a manner that protects USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Chris Korleski 

Commenter Organization: Ohio Environmental Protection Agency (Ohio EPA) 

EPA Letter ID: 0390 

EPA Comment ID: 28310 

Comment: notice of data availability and request of comments. Ohio EPA agrees that the 

request for a waiver should include: site specific geologic and hydrogeologic 

information; be reviewed in consultation with the Drinking Water Program; and be 

338
optional for adoption by state programs with primacy. 

Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpose 

of the UIC requirements. The waiver approach establishes extensive site-specific geologic and 

hydrogeologic information related to injecting above or between USDWs that the owner or operator 

must submit and the Director must consider, in consultation with PWSS Directors, to ensure that 

water supplies in the area and all USDWs are protected. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from lines 35 to 38, which is an excerpt from the previous section, 

lines 32 to 38. This comment appears twice in this report, once for each set of line numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3240 3.2.4. Comments that the Approach Requests Too Much Data (seeking 

comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27870 

Comment: While the NDIC is supportive of allowing injection of CO2 above a USDW, the 

proposed waiver process is too onerous. EPA has not shown how injection above a 

USDW poses any additional risk which warrants the significant increase in 

permitting requirements. Injection below the lowermost USDW or above a USDW both 

require confinement of the injection stream and formation fluids from upward or 

downward migration, there is no difference. 

339
Individual Response: EPA believes that the information required to obtain a waiver is necessary to 

ensure that the owner or operator collects information and demonstrates to the Director that the 

injection zone is suitable for GS, is confined by confining units above and below the injection zone, 

and that well construction, operation, and monitoring are tailored for the site and take into 

consideration the presence of USDWs above and below the injection zone. Because USDW protection 

is the priority of the GS rule, owners or operators seeking waivers must provide a supplemental report 

(the GS Class VI injection depth waiver application report), referenced at §146.82(d) and outlined at 

§146.95(a), with their Class VI permit applications. This report, suggested by commenters, is 

designed to ensure that all waiver information is discrete (from the permit application) and can be 

made available to the Director, PWSS Directors, and the public when the waiver is publicly noticed 

with the draft Class VI permit application. The Agency believes that this report and requirements at 

§146.95 are complementary and not redundant of the Class VI permit application requirements. 

Furthermore, to eliminate concerns about duplication or redundancy, the requirements at §146.82(d) 

clarify that the supplemental report is not part of the permit application. 

EPA believes that that injection for the purpose of GS into non-USDW formations above the lowermost 

USDW warrants tailored requirements to address the unique challenges and risks relative to injection 

below the lowermost USDW. For example, there is a risk of downward migration of fluids if there is no 

lower confining layer or inadequate confinement. In addition, there is potential that wells will be drilled 

through the injection zone in the future to reach USDWs. EPA believes that the additional 

requirements that apply to owners or operators of Class VI wells granted a waiver of the injection 

depth requirements at §146.95 will provide additional considerations for the owner or operator and 

Director when permitting such wells to ensure protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Olon Plunk 

Commenter Organization: Xcel Energy, Inc. 

EPA Letter ID: 0344 

EPA Comment ID: 27875 

Comment: As proposed, the waiver applicant would be required to submit additional site 

specific information prior to completing a Class VI permit application. The 

waiver process should not include requirements that are redundant to the 

permitting process. In addition, the waiver process needs to have clear 

guidelines for decision makers that review the waiver applications to ensure a 

340
transparent and predictable process for applicants and interested parties. 

Individual Response: EPA believes that the information required to obtain a waiver is necessary to 

ensure that the owner or operator collects information and demonstrates to the Director that the 

injection zone is suitable for GS, is confined by confining units above and below the injection zone, 

and that well construction, operation, and monitoring are tailored for the site and take into 

consideration the presence of USDWs above and below the injection zone. Because USDW protection 

is the priority of the GS rule, owners or operators seeking waivers must provide a supplemental report 

(the GS Class VI injection depth waiver application report), referenced at §146.82(d) and outlined at 

§146.95(a), with their Class VI permit applications. This report, suggested by commenters, is 

designed to ensure that all waiver information is discrete (from the permit application) and can be 

made available to the Director, PWSS Directors, and the public when the waiver is publicly noticed 

with the draft Class VI permit application. The Agency believes that this report and requirements at 

§146.95 are complementary and not redundant of the Class VI permit application requirements. 

Furthermore, to eliminate concerns about duplication or redundancy, the requirements at §146.82(d) 

clarify that the supplemental report is not part of the permit application. 

The final GS rule also contains a clear and transparent review process. Section 146.95(b) establishes 

considerations that the UIC Director must assess when evaluating a waiver application to ensure that 

USDW protection, site-specific drinking water resource issues, and the use and impact of GS 

technologies are considered and documented. Section 146.95(c) requires the Director to give public 

notice, as part of the permit application process, including notice that a waiver application has been 

submitted. If the permitting authority receives comments on the injection depth waiver during the 

public comment period for both the waiver and the permit application, the Director in consultation with 

the Regional Administrator, must evaluate comments prior to providing a recommendation to the 

Regional Administrator regarding a waiver and issuing the Class VI permit.

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

341
Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28074 

Comment: Ultimately, in drafting a final rule, EPA should strive to develop clear 

guidelines for decision makers in evaluating waiver applications as well as the 

development of a transparent and, to the extent possible, outcome-predictable 

process to provide guidance for future applicants. In terms of the substantive 

requirements for waiver applicants, the Agency should guard against the 

insertion of unnecessary complexity and redundancy into the process that bring 

no corresponding increase in protection of USDWs. 

Individual Response: EPA believes that the information required to obtain a waiver is necessary to 

ensure that the owner or operator collects information and demonstrates to the Director that the 

injection zone is suitable for GS, is confined by confining units above and below the injection zone, 

and that well construction, operation, and monitoring are tailored for the site and take into 

consideration the presence of USDWs above and below the injection zone. Because USDW protection 

is the priority of the GS rule, owners or operators seeking waivers must provide a supplemental report 

(the GS Class VI injection depth waiver application report), referenced at §146.82(d) and outlined at 

§146.95(a), with their Class VI permit applications. This report, suggested by commenters, is 

designed to ensure that all waiver information is discrete (from the permit application) and can be 

made available to the Director, PWSS Directors, and the public when the waiver is publicly noticed 

with the draft Class VI permit application. The Agency believes that this report and requirements at 

§146.95 are complementary and not redundant of the Class VI permit application requirements. 

Furthermore, to eliminate concerns about duplication or redundancy, the requirements at §146.82(d) 

clarify that the supplemental report is not part of the permit application. 

The final GS rule also contains a clear and transparent review process. Section 146.95(b) establishes 

considerations that the UIC Director must assess when evaluating a waiver application to ensure that 

USDW protection, site-specific drinking water resource issues, and the use and impact of GS 

technologies are considered and documented. Section 146.95(c) requires the Director to give public 

notice, as part of the permit application process, including notice that a waiver application has been 

submitted. If the permitting authority receives comments on the injection depth waiver during the 

public comment period for both the waiver and the permit application, the Director in consultation with 

the Regional Administrator, must evaluate comments prior to providing a recommendation to the 

Regional Administrator regarding a waiver and issuing the Class VI permit.

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

342
that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28133 

Comment: In terms of the substantive requirements for waiver applicants, the Agency 

should guard against the insertion of unnecessary complexity and redundancy into 

the process that bring no corresponding increase in protection of USDWs. 

Individual Response: EPA believes that the information required to obtain a waiver is necessary to 

ensure that the owner or operator collects information and demonstrates to the Director that the 

injection zone is suitable for GS, is confined by confining units above and below the injection zone, 

and that well construction, operation, and monitoring are tailored for the site and take into 

consideration the presence of USDWs above and below the injection zone. Because USDW protection 

is the priority of the GS rule, owners or operators seeking waivers must provide a supplemental report 

(the GS Class VI injection depth waiver application report), referenced at §146.82(d) and outlined at 

§146.95(a), with their Class VI permit applications. This report, suggested by commenters, is 

designed to ensure that all waiver information is discrete (from the permit application) and can be 

made available to the Director, PWSS Directors, and the public when the waiver is publicly noticed 

with the draft Class VI permit application. The Agency believes that this report and requirements at 

§146.95 are complementary and not redundant of the Class VI permit application requirements. 

Furthermore, to eliminate concerns about duplication or redundancy, the requirements at §146.82(d) 

clarify that the supplemental report is not part of the permit application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

343
Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28148 

Other EPA Comment Codes and Descriptions: 3310 3.3.1. Site Characterization 

Comment: E. Waiver application should not require regional characterization of the entire 

basin 

As described above, performing basin-scale evaluations should be the 

responsibility of a government agency, not an individual company. Requiring a 

regional characterization of the entire basin only in those cases where the 

proposed injection is above the lowermost USDW is arbitrary and overly 

burdensome. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. The Agency acknowledges that basin scale 

assessments are currently commonly conducted for other purposes including oil and gas production. 

EPA believes that the information required to obtain a waiver is necessary to ensure that the owner or 

operator collects information and demonstrates to the Director that the injection zone is suitable for 

GS, is confined by confining units above and below the injection zone, and that well construction, 

operation, and monitoring are tailored for the site and take into consideration the presence of USDWs 

above and below the injection zone. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28156 

344
Comment: While we believe that the waiver process described in the NODA offers potential 

advantages, we recognize that the process also includes requirements that may 

not be necessary, nor achieve the intended benefits. 

Individual Response: EPA believes that the information required to obtain a waiver is necessary to 

ensure that the owner or operator collects information and demonstrates to the Director that the 

injection zone is suitable for GS, is confined by confining units above and below the injection zone, 

and that well construction, operation, and monitoring are tailored for the site and take into 

consideration the presence of USDWs above and below the injection zone. Because USDW protection 

is the priority of the GS rule, owners or operators seeking waivers must provide a supplemental report 

(the GS Class VI injection depth waiver application report), referenced at §146.82(d) and outlined at 

§146.95(a), with their Class VI permit applications. This report, suggested by commenters, is 

designed to ensure that all waiver information is discrete (from the permit application) and can be 

made available to the Director, PWSS Directors, and the public when the waiver is publicly noticed 

with the draft Class VI permit application. The Agency believes that this report and requirements at 

§146.95 are complementary and not redundant of the Class VI permit application requirements. 

Furthermore, to eliminate concerns about duplication or redundancy, the requirements at §146.82(d) 

clarify that the supplemental report is not part of the permit application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3300 3.3. Comments on Specific Elements of the Waiver Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

345
EPA Letter ID: 0343 

EPA Comment ID: 27871 

Comment: Since there is no real additional risk, the following areas highlighted in the 

NODA are unnecessary: supplement to Emergency Response Plan; additional 

financial responsibility; need to identify alternative injection sites; 

community needs, demands, and supply from drinking water resources; planned 

needs, potential and/or future use of USDWs and non-USDWs in area; planned or 

permitted water, hydrocarbon, or mineral resource exploitation potential of the 

proposed injection formation and other formations both above and below the 

injection zone to determine if there are any plans to drill through the 

formation to access resources in or beneath the proposed injection zone; 

proposed plan for securing alternative resources or treating USDW in the event 

of contamination related to Class VI injection activity; more stringent 

injection pressure limitations; and increased formation fluid and ground water 

sampling and monitoring above and below the injection zone in concert with local 

water suppliers. 

Individual Response: EPA believes that that injection for the purpose of GS into non-USDW 

formations above the lowermost USDW warrants tailored requirements to address the unique 

challenges and risks relative to injection below the lowermost USDW. For example, there is a risk of 

downward migration of fluids if there is no lower confining layer or inadequate confinement. In 

addition, there is potential that wells will be drilled through the injection zone in the future to reach 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements at §146.95 will provide additional 

considerations when permitting such wells to ensure protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27872 

Comment: One item of particular concern is the planned needs, potential and/or future use 

of USDWs and non-USDWs in area. The inclusion of non-USDWs is broad and 

undefined. What non-USDWs are of concern and why? This information on these 

346
formations, if not the injection or confining zones, is of little value and 

provides no additional protection. Nothing about the location of the injection 

zone being located above a USDW makes this any more relevant than if the 

injection zone is below the lowermost USDW 

Another area of concern is the community needs, demands, and supply from 

drinking water resources, and the planned needs, potential and/or future use of 

USDWs and non-USDWs in area. This appears to require something similar to an 

aquifer exemption for the entire stratigraphic column. 

Also of concern is the planned or permitted water, hydrocarbon, or mineral 

resource exploitation potential of the proposed injection formation and other 

formations both above and below the injection zone to determine if there are any 

plans to drill through the formation to access resources in or beneath the 

proposed injection zone. The same exploitation of various formations can also 

take place if the injection is limited to below the lowermost USDW. This 

information is of little value and provides no additional protection. 

Individual Response: The requirements for consideration of community needs, demands, and supply 

from drinking water resources; planned needs, potential, and/or future use of USDWs and non-USDWs 

in the area; and planned or permitted water, hydrocarbon, or mineral resource exploitation potential 

are designed to ensure that USDW protection, site-specific drinking water resource issues, and the use 

and impact of GS technologies are considered and documented. The final GS rule retains these 

considerations at §146.95(b). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28264 

Comment: NACCSA encourages the Agency to ensure that any waiver provisions include 

specific guidelines for evaluation of and decisions on waiver applications. The 

NODA includes a list of topics decision makers could be required to consider, as 

well as a description of the types of additional information that may be sought 

347
from waiver applicants. While NACCSA understands that not all decision points at 

issue in every situation can be specifically catalogued in a regulation, and 

that some discretion is appropriately vested in program directors, providing 

clear guidelines regarding the waiver process will bring needed certainty and 

predictability to the process. 

Individual Response: EPA is developing guidance on the injection depth waiver process. The 

guidance describes the recommended approach an owner or operator may follow when submitting a 

waiver application, processing waiver applications by the UIC and PWSS Program Directors, and 

additional considerations that may apply to projects that have been issued waivers. This guidance will 

be available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27942 

Comment: - It is unclear that technology has been developed for drilling through 

injection zones containing stored carbon dioxide without releasing some of the 

stored gas. EPA should insist that demonstration of such technologies be 

performed before considering a waiver program. 

-The risk of damaging water or mineral resources will be greatly increased, and 

there needs to be an adequate mechanism for compensating water utilities and 

other resource owners for remedial actions that must be taken to restore or 

replace beneficial uses. 

Individual Response: EPA believes that technologies and past experience exist to inject through 

over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry experience in 

drilling through shallow pockets of gas or other zones that have higher pressures). EPA has reviewed 

information on these types of projects and has determined that, if properly constructed, wells can be 

drilled through pressurized zones without causing fluid movement. However, to provide additional 

USDW protection and ensure that any planned drilling is conducted appropriately, the final GS rule 

348
requires the Director to consider planned or permitted water, hydrocarbon, or mineral resource 

exploitation potential of the proposed injection formation and other formations both above and below 

the injection zone to determine if there are any plans to drill through the formation to access 

resources in or beneath the proposed injection zone/formation as specified in §146.95(b)(1)(vii).

EPA clarifies that the financial responsibility and emergency and remedial response requirements in 

the final GS rule, at §§146.85 and 146.94, are designed to ensure that actions can be taken 

expeditiously to address impacts to drinking water supplies and that resources are available to fund 

those actions. EPA adds that, for GS projects where injection depth waivers are sought, the Director 

must also consider the proposed emergency and remedial response plan, as well as a demonstration 

of financial responsibility, in making a determination on whether to grant a waiver per 

§146.95(b)(1)(iv). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 278 to 286, which is an excerpt from a previous 

section, lines 226 to 286. This comment appears twice in this report, once for each set of line 

numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27992 

Comment: Comment No. 49 

Page 44811 

Issue Topic from EPA's NODA 

These Directors would consider factors such as: 

* * * 

-The potential capacity of the geologic formation to sequester CO2, accounting 

for the availability of alternative injection sites; 

* * * 

Carbon Sequestration Council Comments 

There are many factors that project developers must consider in selecting an 

349
appropriate site for geologic sequestration. A review of the entire selection 

process and alternatives is not an appropriate task for Directors; there should 

not be a need to make comparison demonstrations to prove one site better than 

another if the proposed GS site meets all of the permitting requirements. 

Individual Response: EPA clarifies that the intent of the requirement to consider alternatives 

ensures the waiver approach is applied only when needed. EPA anticipates that issuance of waivers 

will be limited to circumstances where there are deep USDWs and/or where the lack of a waiver of 

injection depth requirements would result in impractical or technically infeasible well construction, and 

where USDW protection is demonstrated and maintained through the life of the GS project. EPA 

clarifies that the responsibility for making a demonstration that no suitable alternative injection sites 

exist is the responsibility of the owner or operator, not the Director. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27993 

Other EPA Comment Codes and Descriptions: 3350 3.3.5. Requirement to Submit Waiver 

Application to UIC and PWSS Program Directors 

Comment: Comment No. 50 

Page 44811 

Issue Topic from EPA's NODA 

- Planned needs, potential and/or future use of USDWs and non- USDWs in the 

area; 

Carbon Sequestration Council Comments 

Concrete plans for future use of formations can and should be submitted to EPA 

in comments from the PWSS Director for consideration but must be considered 

within the context of the SDWA endangerment standard for protecting USDWs. 

350
Comment No. 51 

Page 44811 

Issue Topic from EPA's NODA 

- Planned (or permitted) water, hydrocarbon, or mineral resource exploitation 

potential of the proposed injection formation and other formations both above 

and below the injection zone - to determine if there are any plans to drill 

through the formation to access resources in or beneath the proposed injection 

zone/formation; 

Carbon Sequestration Council Comments 

Same comment as 50 above. 

Individual Response: EPA agrees that information on planned and future uses of USDWs and water 

and mineral resources near an injection zone should be considered by the UIC and PWSS program 

staff in the context of USDW protection, and believes that the final GS rule requirements for 

consultation allow consideration from both perspectives. 

EPA believes that the requirements at §146.95 for owners and operators seeking injection depth 

waivers are intended to add to and modify the requirements that all GS well owners or operators must 

meet to ensure that the proposed site is evaluated in the context of the presence of USDWs above and 

below the injection zone. 

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

351
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27994 

Other EPA Comment Codes and Descriptions: 3340 3.3.4. Financial Responsibility 

Comment: Comment No. 52 

Page 44811 

Issue Topic from EPA's NODA 

- The proposed plan for securing alternative resources or treating USDW 

formation waters in the event of contamination related to the Class VI injection 

activity; and, 

Carbon Sequestration Council Comments 

This is a matter to be addressed on a site-specific basis by the operator as 

part of the emergency response plan. It should not be required in all instances 

and should be a part of the plan only where chosen as an approach by the 

owner/operator to meet the regular permit requirement for preparation and 

maintenance of that plan. 

Individual Response: As described above, the requirements at §146.95 for owners and operators 

seeking injection depth waivers are intended to add to and modify the requirements that all GS well 

owners or operators must meet, including those for financial responsibility and emergency and 

remedial response, to ensure that the proposed site is evaluated in the context of the presence of 

USDWs above and below the injection zone. 

EPA clarifies that, for GS projects where injection depth waivers are sought, the Director must also 

consider the proposed emergency and remedial response plan in making a determination whether to 

grant a waiver per §146.95(b)(1)(iv). EPA believes that additional consideration of the emergency and 

remedial response plan, which is required of all owners or operators per §146.94, in the context of 

USDWs above and below the injection zone is appropriate where injection depth waivers are being 

considered. 

EPA Team Member: 

Draft Status: 

352
Date Uploaded: 05-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27995 

Comment: Comment No. 53 

Page 44811 

Issue Topic from EPA's NODA 

- Any other locally applicable considerations. 

Carbon Sequestration Council Comments 

Such considerations would be appropriate to the extent related to the 

endangerment standard that is applied by the Director in making permitting 

decisions. 

Individual Response: EPA agrees that any additional information requested should be limited to that 

which supports decisions regarding waivers, based on the potential for USDW endangerment. The final 

GS rule, at §146.95(B)(1)(ix), stipulates that the Director consider "any other applicable 

considerations or information requested by the Director." EPA believes this requirement provides the 

Director with appropriate authority to consider all site-specific information and promotes the flexibility 

sought by commenters. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

353
EPA Letter ID: 0383 

EPA Comment ID: 28108 

Comment: - Any project accepted under the waiver program should be treated as a case 

study, with limitations on the amount of CO2 to be injected and/or the time span 

of the project, coupled with increased frequency of results of monitoring data 

to indentify potential impacts of GS operations, until long- term assessments of 

the monitoring data can be completed. 

- An emergency response plan for each project should identify failure scenarios 

along with mitigation and remediation plans and responsibilities. 

- Long-term financial responsibility (> 50 years) must be assigned to ensure the 

viability of current and future water supplies that could be negatively impacted 

by a GS project. The contaminating party must not be allowed to walk away. 

Individual Response: EPA clarifies that all decisions regarding waivers (and all aspects of GS project 

permitting) will be made on a site-specific basis. The waiver approach establishes requirements for 

extensive site-specific information related to injecting above or between USDWs that the owner or 

operator must submit and the Director must consider, in consultation with PWSS Directors, to ensure 

that water supplies in the area and all USDWs are protected. Furthermore, owners or operators 

granted injection depth waivers are subject to additional requirements at §146.95(f), which include 

requirements to monitor above and below the injection zone in order to ensure protection of USDWs 

underlying and overlying the injection zone during both well operation and the post-injection site care 

period. 

EPA clarifies that, in the final GS rule, for GS projects where injection depth waivers are sought, the 

Director must also consider the proposed emergency and remedial response plan in making a 

determination whether to grant a waiver as specified in §146.95(b)(1)(iv). 

Regarding long-term liability, under the final GS rule, once an owner or operator has met all 

regulatory requirements under Part 146 for Class VI wells and the Director has approved site closure 

pursuant to requirements at §146.93, the owner or operator will generally no longer be subject to 

enforcement for regulatory noncompliance. Furthermore, their financial instrument as required under 

§146.85 will be released if it was not used. However, even if a site closure is approved under §146.93, 

an owner or operator may be held liable for regulatory noncompliance (including violation of 40 CFR 

144.12) in certain circumstances. For example, an owner or operator may be held liable for regulatory 

noncompliance even after site closure was approved if the Director relied on erroneous information 

(e.g., erroneous modeling data) provided by the owner or operator when approving site closure. 

354
Separate from EPA’s authority to enforce regulatory compliance, an owner or operator may be subject 

to a §1431 response order even after proper site closure is approved under §146.93. Under §1431 the 

Administrator may require an owner or operator to take necessary response measures if he or she 

receives information that a contaminant is present or is likely to enter a public water system or an 

USDW, which may present an imminent and substantial endangerment to the health of persons, and 

the appropriate State and local authorities have not acted to protect the health of such persons. The 

action may include issuing administrative orders or commencing a civil action for appropriate relief 

against the owner or operator of a Class VI well. If the owner or operator fails to comply with the 

order, they may be subject to a civil penalty for each day in which such violation occurs or failure to 

comply continues. 

Furthermore, after site closure an owner or operator may remain liable under tort and other remedies, 

or under other federal statutes including, but not limited to, Clean Air Act, 42 U.S.C. §§ 7401-7671; 

CERCLA, 42 U.S.C. § 9601-9675; and RCRA, 42 U.S.C. § 6901-6992. Please note that EPA does not 

have authority to transfer SDWA or other legal liability for Class VI wells to the State or federal 

government or a third-party fund. 

For additional information on the financial responsibility requirements for GS projects, see the 

preamble to the final rule and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-OCT-10 

Notes: This comment contains text that is later repeated in lines 160 to 161 and 163 to 165. Part of 

this comment appears three times in this report, once for each set of line numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3310 3.3.1. Site Characterization 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

355
Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 28293 

Comment: Moreover, CURC requests that EPA demonstrate that certain of the prescribed 

requirements in the waiver information submittal are universally necessary to 

protect USDW. For example, it is not clear why it is necessary to show that 

"the injection matrix is not dissolved as a result of injection." It is our 

understanding that the nature of these systems will result in slow chemical 

reactions between the rock matrix and the injected CO2, which means that some of 

the rock material could dissolve. Similarly, it is not clear to us that the 

same structural requirements are appropriate for downward migration of the 

inherently buoyant injectate, as are needed for limiting upward migration. A 

requirement for a clear demonstration of the inability of injected CO2 to reach 

any deep USDW is appropriate, but a universal requirement for a mandatory 

impermeable barrier below the injection zone may not be. 

Individual Response: EPA clarifies that the requirements at §146.95 for owners and operators 

seeking injection depth waivers are intended to add to and modify the requirements that all GS well 

owners or operators must meet, including those for site-specific geologic characterization and 

information on potential mineralization reactions, to ensure that the proposed site is evaluated in the 

context of the presence of USDWs above and below the injection zone. EPA believes that the presence 

of confining zones above and below the injection zone are appropriate where injection depth waivers 

are employed because the area of increased pressure ahead of the CO2 plume, can potentially 

displace saline, native fluids into USDWs above or below the injection zone.

EPA anticipates that issuance of waivers will be limited to circumstances where there are deep USDWs 

and/or where the lack of a waiver of injection depth requirements would result in impractical or 

technically infeasible well construction, and where USDW protection is demonstrated and maintained 

through the life of the GS project. 

The GS regulation requires the owner or operator to submit information on the porosity, permeability, 

mineralogy, and geochemistry of the targeted injection and confining zones and on the compatibility of 

the CO2 stream with fluids in the injection zone and minerals in both the injection and confining zones 

as specified in §146.82(c)(3). The data can help the Director determine the potential for geochemical 

reactions between the injectate (CO2) and the host geologic formations, which could result in the 

plugging of pore spaces or the dissolution of formation minerals. For additional information on site 

characterization for GS projects, see the preamble to the final rule and the responses to comments on 

the proposed GS rule. 

EPA Team Member: 

Draft Status: 

356
Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

EPA Letter ID: 0339 

EPA Comment ID: 28011 

Comment: C. SWRCB Comment #3 on: "D. - Evaluation of concerns about injection depth for 

Class VI wells": 

Laterally continuous, impermeable confining units on large scale have not been 

found to exist in nature. 

Laterally continuous, CO2 injection zones with the required porosity and 

chemistry are very rare in nature. 

Continuous zone free of fractures and faults have not been found to exist in 

nature. 

Characterization of fractures and faults deep under ground is not currently 

possible; the proposed Yucca Mountain waste repository site characterization 

process includes access to deep zone through miles of tunnels and boreholes. 

Even with all of this, there are still uncertainties about its safety. 

Individual Response: EPA disagrees that laterally continuous, impermeable confining zones and 

laterally continuous injection zones are rare in nature. Existing geologic structures such as gas and oil 

fields and natural CO2 domes have shown the ability to trap and retain gases for millions of years. 

Many owners or operators of injection projects have made similar demonstrations to satisfy UIC 

permitting requirements (e.g., Class I through V), including evaluating the existence of laterally 

continuous injection and confining zones and the absence of transmissive faults and fractures. For 

additional information on site characterization for GS projects, see the preamble to the final rule and 

the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

357
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28082 

Comment: process. 

Page 44811: "(3) An injection zone and confining formations free of transmissible 

fractures and faults." 

EPRI COMMENT#5: EPRI does not see a need to exclude injection zones containing 

transmissible fractures or faults from being considered as geologic storage 

targets as long as these transmissible features are not present in the 

overlying/underlying confining units. Fractured formations often have excellent 

permeability promoting high injection rates at relatively low injection 

pressures. Lower injection pressures will lead to lower risk of fracturing the 

adjacent confining unit(s). 

Individual Response: EPA clarifies that the requirement refers to the confining zone. The final GS 

rule requires a demonstration that the confining units are free of transmissive faults and fractures per 

§146.95(a)(2). For additional information on site characterization for GS projects, see the preamble to 

the final rule and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28083 

Comment: Page 44811, "(4) A characterization of regional fracture properties and a 

demonstration that such fractures will not interfere with injection, serve as 

conduits, or endanger USDWs." 

358
ERPI COMMENT#6: EPRI does not understand the need for this requirement given the 

EPA’s position that the waiver should only be granted for confining units free 

of transmissible faults and fracture as quoted above. Why would a regional 

characterization of the properties of these features be required if transmissible 

members of the population can't be present in the confining unit in order to 

receive the waiver? 

EPRI believes a regional characterization of fracture properties should not be 

required for injection zones too. A regional assessment of fracture properties 

is somewhat academic and may not aid the project proponent and regulator in 

assessing local project safety. Local rock properties and stresses (past and 

present) control evolution of local fracture patterns and their corresponding 

hydraulic properties. Regional stresses and rock properties may be significantly 

different than local conditions leading to erroneous conclusions. Therefore, 

fracture characterization, if required at all, should be limited to the Area of 

Review where local features would potentially be present and serve as conduits. 

Individual Response: EPA clarifies that the requirement for regional characterization of fracture 

properties applies to the confining zone. The final GS rule requires a demonstration that the confining 

units are free of transmissive faults and fractures and requires regional characterization of fracture 

properties as specified in §146.95(a)(2) to support a determination that no fractures will interfere with 

injection, serve as conduits, or endanger USDWs. This requirement applies to all GS projects as 

specified in §146.82(a), and the requirements at §146.95 for owners and operators seeking injection 

depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for site-specific geologic characterization of faults and fractures, 

to ensure that the proposed site is evaluated in the context of the presence of USDWs above and 

below the injection zone. EPA anticipates that issuance of waivers will be limited to circumstances 

where there are deep USDWs and/or where the lack of a waiver of injection depth requirements would 

result in impractical or technically infeasible well construction, and where USDW protection is 

demonstrated and maintained through the life of the GS project. For additional information on site 

characterization for GS projects, see the preamble to the final rule and the responses to comments on 

the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

359
Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28084 

Comment: Page 44811: "The potential capacity of the geologic formation to sequester CO2, 

accounting for the availability of alternative injection sites;" 

EPRI COMMENT#7: Presumably the project proponent will have screened numerous 

sites (if available) before selecting an optimum location that meets the 

requirements of the EPA rule as finally promulgated (including capacity) and the 

economic, technical and non-technical needs of the project. However, numerous 

factors enter into the decision to develop a GS project and submit a permit 

application, not just "capacity" and "availability of alternative injection 

sites." Therefore, the need for this requirement is not clear. 

Individual Response: EPA clarifies that the intent of the requirement to consider alternative injection 

sites ensures the waiver approach is applied only when needed. EPA anticipates that issuance of 

waivers will be limited to circumstances where there are deep USDWs and/or where the lack of a 

waiver of injection depth requirements would result in impractical or technically infeasible well 

construction, and where USDW protection is demonstrated and maintained through the life of the GS 

project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28222 

Comment: 

-Added Flexibility to Site-Determinations for GS Injections of CO2: EPA 

initially proposed that the injection of CO2 be confined primarily to areas 

below the lowermost formation containing an underground source of drinking water 

(USDW). Such an approach would preclude injection of CO2 into zones between and 

above USDWs and would prohibit injection into shallow formations such as coal 

seams and basalts. 

360
In its August 31, 2009 supplement, EPA presents an alternative to the very rigid 

"one- size-fits-all" injection depth approach suggested in the initial 

rulemaking. Under the proposed alternative, the Agency would add a waiver 

process. As the Agency puts it: 

"The proposed Class VI injection depth requirements would remain unchanged but 

would allow an owner or operator seeking to inject above and/or between USDWs to 

apply for a waiver from the proposed injection depth requirements. The owner or 

operator would be required to demonstrate to regulatory authorities that such 

injection can be undertaken and completed in a manner that prevents fluid 

movement into overlying (and underlying) USDWs, thereby preventing the 

endangerment of public health from USDW contamination." 

Individual Response: EPA acknowledges the commenter's support of the waiver approach. The 

requirements at §146.95 for owners and operators seeking injection depth waivers are intended to 

add to and modify the requirements that all GS well owners or operators must meet, including those 

for site-specific geologic characterization, to ensure that the proposed site is evaluated in the context 

of the presence of USDWs above and below the injection zone and provide flexibility sought by 

commenters. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Joyce Dillard 

Commenter Organization: 

EPA Letter ID: 0364 

EPA Comment ID: 28291 

Comment: Will waivers negate any of the scientific evidence and make sequestration 

restrictions mute and potentially dangerous. What are the criteria for 

earthquake areas. 

Individual Response: EPA stresses that determinations about the appropriateness of waivers will be 

based on carefully planned and collected site-specific information. All owners or operators of proposed 

GS sites must provide extensive geologic information about the site, including its seismic history per 

361
§146.82(a)(3)(v). For additional information on geologic characterization of GS sites, see the 

preamble to the final rule and the responses to comments on the proposed GS rule.

EPA clarifies that the requirements at §146.95 for owners and operators seeking injection depth 

waivers are intended to add to and modify the requirements that all GS well owners or operators must 

meet, including those for site-specific geologic characterization and an evaluation of seismic risk, to 

ensure that the proposed site is evaluated in the context of the presence of USDWs above and below 

the injection zone. EPA anticipates that issuance of waivers will be limited to circumstances where 

there are deep USDWs and/or where the lack of a waiver of injection depth requirements would result 

in impractical or technically infeasible well construction, and where USDW protection is demonstrated 

and maintained through the life of the GS project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: B. Peter McGrail 

Commenter Organization: Pacific Northwest National Laboratory 

EPA Letter ID: 0375 

EPA Comment ID: 28163 

Comment: Also on pg. 44811 under Site Characterization, the following statement is made: 

"..and appropriate soilrock chemistry (so as to ensure that the injection matrix 

is not dissolved as a result of injection);". EPA provides no context, limits, 

or constraints on this requirement, which again would only apply to those 

seeking a waiver under these draft rules. First, the perturbation in groundwater 

chemistry induced from CO2 injection virtually guarantees that some amount of 

matrix dissolution will occur in any foreseeable type of geologic reservoir. A 

strict legal interpretation of this statement would potentially exclude all 

reservoirs in the U.S. for GS. In reality, matrix dissolution reactions are 

inherently limited due to slow dissolution kinetics in most reservoirs and the 

high SiO2 content of most siliclastic and volcanic rocks of interest for GS. In 

basalts, some matrix dissolution is desired as it is a precursor step towards 

eventual precipitation of carbonate minerals that permanently sequester the CO2 

in these reservoirs. EPA statement regarding a matrix dissolution requirement 

should at least be heavily caveated but preferentially removed in any future 

drafts of these regulations. 

362
Individual Response: EPA clarifies that the GS regulation requires all owners or operators to submit 

information on the porosity, permeability, mineralogy, and geochemistry of the targeted injection and 

confining zones and on the compatibility of the CO2 stream with fluids in the injection zone and 

minerals in both the injection and confining zones at §146.82(c)(3). The data can help the Director 

determine the potential for geochemical reactions between the injectate (CO2) and the host geologic 

formations, which could result in the plugging of pore spaces or the dissolution of formation minerals. 

For additional information on site characterization for GS projects, see the preamble to the final rule 

and the responses to comments on the proposed GS rule.

EPA is developing guidance on site characterization of GS sites to assist owners or operators and 

Directors in evaluating the requirements under §146.82. The guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27976 

Comment: Comment No. 33 

Page 44809-10 

Issue Topic from EPA's NODA 

Class II and Class III owners and operators of sites where injection is taking 

place above and between USDWs must identify and demonstrate upper and lower 

impermeable confining units. These confining units serve as barriers to fluid 

movement and pressure and must ensure continuous injectate isolation, 

confinement, and USDW protection. Identification of such units is conducted 

through analysis of sonic and resistivity logs, drill stem tests, and wire line 

tests. 

Carbon Sequestration Council Comments 

The requirement to demonstrate the suitability of the confining unit below the 

363
proposed injection zone is reasonable and technically feasible. Other site 

characterization requirements are not significantly different than for geologic 

storage below the lowermost USDW. 

As reflected in recommendations presented by the Multi-Stakeholder Discussion 

participants in the MSD Recommendation Letters of December 23, 2008 and October 

9, 2009, which the Council and many of our members signed, the requirement that 

GS take place in formations beneath the lowermost USDW should not be imposed on 

GS taking place in oil and gas reservoirs, many of which are located above the 

lowermost USDW and have demonstrated containment capabilities over geologic time 

and through many years of oil and gas production operations. 

Individual Response: EPA acknowledges the comment. For additional information on 

characterization of GS sites, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27987 

Comment: Comment No. 44 

Page 44811 

Issue Topic from EPA's NODA 

The waiver application would need to demonstrate: 1) Laterally continuous, 

impermeable confining units above and below the injection zone adequate to 

prevent fluid movement and pressure buildup; 2) A laterally continuous injection 

zone/formation with adequate injectability, including sufficient porosity and 

permeability, and appropriate soil-rock chemistry (so as to ensure that the 

injection matrix is not dissolved as a result of injection); 3) An injection 

zone and confining formations free of transmissive fractures and faults; and, 4) 

364
A characterization of regional fracture properties and a demonstration that such 

fractures will not interfere with injection, serve as conduits, or endanger 

USDWs. 

Carbon Sequestration Council Comments 

The information identified in item 3 is important for confining zones, but not 

necessary for things that occur solely within an injection zone. The Council 

has joined with other MSD participants in recommending a revised definition for 

transmissive faults or fractures that takes into account the potential for GS 

above the lowermost USDW: 

The recommendation recognizes that EPA's proposed rule in §146.83(a)(2) would 

require a confining zone(s) that is free of transmissive faults or fractures, 

while proposed §146.81 would define this term as "A fault or fracture that has 

sufficient permeability and vertical extent to allow fluids to move between 

formations". 

The MSD letter recommends the following modification to the definition in 

§146.81(d) in order to avoid unduly restricting movement that is merely between 

formations: 

"Transmissive fault or fracture means a fault or fracture that has sufficient 

permeability and vertical extent to allow fluids to move beyond a confining 

zone." 

MSD Recommendation Letter, May 14, 2009, Item 3. 

Individual Response: The final GS rule requires owners and operators seeking injection depth 

waivers to demonstrate that the confining units are free of transmissive faults and fractures and that 

such fractures will not interfere with injection, serve as conduits, or endanger USDWs as specified in 

§146.95(a)(2). For additional information on site characterization for GS projects, see the preamble to 

the final rule and the responses to comments on the proposed GS rule.

EPA clarifies that the requirements at §146.95 for owners and operators seeking injection depth 

waivers are intended to add to and modify the requirements that all GS well owners or operators must 

meet, including those for site-specific geologic characterization and consideration of the presence of 

faults and fractures, to ensure that the proposed site is evaluated in the context of the presence of 

USDWs above and below the injection zone. EPA anticipates that issuance of waivers will be limited to 

circumstances where there are deep USDWs and/or where the lack of a waiver of injection depth 

365
requirements would result in impractical or technically infeasible well construction, and where USDW 

protection is demonstrated and maintained through the life of the GS project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28123 

Comment: Fundamentally, proper site selection is critical to a successful GS project. 

Indeed, proper site characterization is the most effective risk management tool 

for GS projects and the best way to ensure protection of USDWs. It serves to 

minimize, if not eliminate, any potential threats to USDWs that GS projects may pose. 

Individual Response: EPA agrees that proper site selection, along with proper construction, 

operation, monitoring, and post closure site care, are the most critical components of a GS project. 

EPA clarifies that the requirements at §146.95 for owners and operators seeking injection depth 

waivers are intended to add to and modify the requirements that all GS well owners or operators must 

meet, including those for site-specific geologic characterization, to ensure that the proposed site is 

evaluated in the context of the presence of USDWs above and below the injection zone. EPA 

anticipates that issuance of waivers will be limited to circumstances where there are deep USDWs 

and/or where the lack of a waiver of injection depth requirements would result in impractical or 

technically infeasible well construction, and where USDW protection is demonstrated and maintained 

through the life of the GS project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28130 

366
Other EPA Comment Codes and Descriptions: 3210 3.2.1. Comments Generally in Support of the 

Approach 

Comment: Fundamentally, proper site selection is critical to a successful GS project. 

Indeed, proper site characterization is the most effective risk management tool 

for GS projects. It serves to minimize, if not eliminate, any potential threats 

to USDW that GS projects may pose. EEI maintains that siting decisions may best 

be made on a project-by- project basis through exercise of the program 

director’s discretion bounded by clear principles for its application, and that 

a blanket prohibition on use of potential receiving formations above the 

lowermost USDW, even where regulatory provisions for a waiver are available, is 

unnecessary. However, allowing for a waiver process would ameliorate many of 

EEI’s concerns with limiting injection and storage to formations below the 

lowermost USDW. 

Individual Response: EPA agrees that proper site selection, along with proper well construction, 

operation, monitoring, and post-injection site care, are critical components of a GS project. EPA 

clarifies that the requirements at §146.95 for owners and operators seeking injection depth waivers 

are intended to add to and modify the requirements that all GS well owners or operators must meet, 

including those for site-specific geologic characterization, to ensure that the proposed site is evaluated 

in the context of the presence of USDWs above and below the injection zone. EPA anticipates that 

issuance of waivers will be limited to circumstances where there are deep USDWs and/or where the 

lack of a waiver of injection depth requirements would result in impractical or technically infeasible 

well construction, and where USDW protection is demonstrated and maintained through the life of the 

GS project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28148 

Other EPA Comment Codes and Descriptions: 3240 3.2.4. Comments that the Approach Requests 

Too Much Data (seeking comment) 

367
Comment: E. Waiver application should not require regional characterization of the entire 

basin 

As described above, performing basin-scale evaluations should be the 

responsibility of a government agency, not an individual company. Requiring a 

regional characterization of the entire basin only in those cases where the 

proposed injection is above the lowermost USDW is arbitrary and overly 

burdensome. 

Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. The Agency acknowledges that basin scale 

assessments are currently commonly conducted for other purposes including oil and gas production. 

EPA believes that the information required to obtain a waiver is necessary to ensure that the owner or 

operator collects information and demonstrates to the Director that the injection zone is suitable for 

GS, is confined by confining units above and below the injection zone, and that well construction, 

operation, and monitoring are tailored for the site and take into consideration the presence of USDWs 

above and below the injection zone. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28574 

Comment: require a separate application process with redundant data submittal. Second, 

the waiver applications should not require the operator to complete a basinlevel study but rather demonstrate no impact on existing adjacent subsurface 

operations such as gas storage, production and geologic sequestration. Third, 

368
Individual Response: The final GS rule focuses on permitting of individual GS wells and therefore 

does not include requirements for basin-scale evaluations. However, EPA agrees that proactive 

management of basin scale concerns to maintain pressures within acceptable ranges is important and 

encourages owners or operators and permitting authorities to communicate planned GS activities to 

maximize coordination and minimize pressure interference. The Agency acknowledges that basin scale

assessments are currently commonly conducted for other purposes including oil and gas production. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3320 3.3.2. AoR and Corrective Action 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27941 

Comment: - EPA’s suggested criteria for approving a GS injection depth waiver includes a 

requirement that the owner/operator identify all artificial penetrations in the 

Area of Review that penetrate the injection zone, the upper and lower confining 

zones, and all USDWs in the area. The stated purpose of this demonstration would 

be to ensure that public water supplies, private wells, and potential future 

water resources are identified and the location of artificial penetrations into 

such formations are known and these artificial penetrations can be appropriately 

plugged during the permitting process. Because drinking water wells are 

artificial penetrations, it appears that they would be plugged, making them 

useless for supplying water. If not, it is unclear how the owner/operator can 

demonstrate that the construction of these wells is equivalent to Class VI well 

369
requirements and thus would not serve as conduits to contaminate USDWs. 

Individual Response: EPA clarifies that, while all wells in the AoR must be identified, only improperly 

plugged wells that penetrate the confining zone must be plugged per §146.84. EPA expects that most 

active drinking water wells would not be completed at depths close to the injection zone for a GS 

project. For additional information on corrective action for GS projects, see the preamble to the final 

rule and the responses to comments on the proposed GS rule.

EPA adds that the requirements at §146.95 for owners and operators seeking injection depth waivers 

are intended to add to and modify the requirements that all GS well owners or operators must meet, 

including those for corrective action, to ensure that the proposed site is evaluated in the context of the 

presence of USDWs above and below the injection zone. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 265 to 276, which is an excerpt from the previous 

section, lines 226 to 286. This comment appears twice in this report, once for each set of line 

numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27988 

Comment: Comment No. 45 

Page 44811 

Issue Topic from EPA's NODA 

Due to the potential risk that artificial penetrations pose as fluid/injectate 

conduits, the owner/operator would need to map and identify all artificial 

penetrations in the AoR that penetrate the injection zone, the upper and lower 

confining zones, and all USDWs in the area. The purpose of this demonstration 

would be to ensure that public water supplies, private wells, and potential 

future water resources are identified and the location of artificial 

penetrations into such formations are known and these artificial penetrations 

can be appropriately plugged during the permitting phase. 

370
Carbon Sequestration Council Comments 

These requirements for the area of review and corrective action are the same as 

would apply to all permit applications. It should not be necessary to plug all 

wells during the permitting phase, only to demonstrate either that wells were 

constructed and/or plugged so as to prevent fluid movement up or down into 

USDWs, or that a plan will be executed to remediate wells that were not 

appropriately constructed and/or plugged. See Bachu and Watson, 2007 for 

characteristics in pre-existing wells that correspond to higher risks for 

leakage. 

[Reference]: Bachu, S. and Watson T., Factors Affecting or Indicating Potential 

Wellbore Leakage, IEA GHG 3rd Wellbore Integrity Network Meeting, Santa Fe, 

2007. 

Individual Response: EPA clarifies that the final GS rule allows phased corrective action as specified 

in an approved AoR and corrective action plan per §146.84. For additional information on corrective 

action for GS projects, see the preamble to the final rule and the responses to comments on the 

proposed GS rule. EPA adds that the requirements at §146.95 for owners and operators seeking 

injection depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for corrective action, to ensure that the proposed site is 

evaluated in the context of the presence of USDWs above and below the injection zone. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3330 3.3.3. Emergency and Remedial Response 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

371
Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27989 

Comment: Comment No. 46 

Page 44811 

Issue Topic from EPA's NODA 

The owner or operator would need to supplement the emergency and remedial 

response plan (submitted as part of the waiver application process and as part 

of the UIC Class VI permit) to ensure protection of USDWs above and below the 

injection zone. The purpose of this plan would be to explain that the owner or 

operator has considered regional water resource issues and has explored 

alternative water supplies or water treatment options to address unanticipated 

movement of the injectate or formation fluids (e.g., CO2, brine, or other 

fluids) into any overlying or underlying USDWs. 

Carbon Sequestration Council Comments 

The requirements described would not be any different from what would be 

required in this context under the original proposed Class VI requirements. To 

the extent that this statement is intended to indicate that multiple or 

duplicate plans must be prepared and submitted, such a requirement would be an 

unwarranted burden on both applicants and permitting agencies. Moreover, such 

an approach could lead to having inconsistent plans for GS projects and wells. 

EPA should clarify exactly what is to be required and should provide that the 

permit and waiver application can be a single submission to the permitting 

agency. It is confusing to refer to a need to "supplement" the emergency and 

remedial response plan when it is clear from the context that any permit 

application for GS injection into a formation above the lowermost USDW will need 

to include these explanations from the outset rather than as a "supplement." 

Individual Response: The requirements at §146.95 for owners and operators seeking injection 

depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for emergency and remedial response, to ensure that the 

proposed site is evaluated in the context of the presence of USDWs above and below the injection 

372
zone. EPA anticipates that issuance of waivers will be limited to circumstances where there are deep 

USDWs and/or where the lack of a waiver of injection depth requirements would result in impractical 

or technically infeasible well construction, and where USDW protection is demonstrated and 

maintained through the life of the GS project. 

In the final GS rule, for GS projects where injection depth waivers are sought, the Director must also 

consider the proposed emergency and remedial response plan in making a determination whether to 

grant a waiver as specified in §146.95(b)(1)(iv). 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional processes that 

may apply to projects that have been issued waivers. This guidance will be available on EPA’s website 

at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28109 

Comment: - An emergency response plan for each project should identify failure scenarios 

along with mitigation and remediation plans and responsibilities. 

Individual Response: EPA believes that the emergency and remedial response plan required at 

§146.94 should focus on actions to be taken in the event of an adverse impact on drinking water 

supplies; such actions should include identifying remediation plans and responsible parties. While the 

plan is not required to identify failure scenarios, EPA expects that owners and operators would 

consider potential failure scenarios in developing the emergency and remedial response plan. EPA is 

developing guidance on preparing all of the required GS project plans, including emergency and 

remedial response plans. This guidance will be available on EPA’s website at 

water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

373
Notes: This comment contains text from lines 160 to 161, which is an excerpt from the previous 

section, lines 154 to 166. This comment appears twice in this report, once for each set of line 

numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3340 3.3.4. Financial Responsibility 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code:

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Nightingale 

Commenter Organization: Illinois Environmental Protection Agency (IEPA) 

EPA Letter ID: 0333 

EPA Comment ID: 28200 

Comment: I. Third Party Wells (page 44811) 

Under the bullet entitled "Emergency and remedial response and financial 

responsibility," the Notice of Data Availability "NODA" discusses evaluation of 

potential future use of resources located below or within the injection zone. If 

a third party chooses to drill into or through the injection zone formation to 

obtain resources in or beneath it, who is responsible for releases that result 

from the construction/operation of a third party well? Should a release to a 

USDW occur due to the actions of a third party, is the owner/operator of the 

injection facility responsible for the cost of the cleanup? It would seem that 

within the AOR any penetrations through the injection zone formation should be 

regulated in some manner as they increase the risk of contamination of USDWs. 

II. Any Potential Contamination (pg 44811) 

Under the bullet entitled "Emergency and remedial response and financial 

responsibility" it states, "The owner/operator would also demonstrate 

sufficient, additional financial responsibility to address any potential 

374
contamination of USDWs above or below the injection zone." Illinois EPA believes 

the regulations should specifically define what "any potential contamination" 

means. Does this mean that the owner/operator must provide financial assurance 

for a worst-case scenario, i.e. a massive release of all CO2 that has been 

sequestered, or some other risked based evaluation? Without a clear 

understanding of what "any potential contamination" means, a wide variety of 

definitions may be developed from region to region as well as from state to 

state. The regulations should be specific enough to provide a consistent 

regulation regardless of which regulatory body has permitting authority. 

Individual Response: In response to the question about third parties drilling through the injection 

zone, EPA clarifies that if an injection well is drilled in the future, the applicable UIC requirements (i.e., 

based on the well class) for AoR and corrective action would apply. The UIC program has no authority 

to address drilling for other purposes. However, EPA anticipates that any applicable permitting process 

would consider prior uses of subsurface formations.

EPA acknowledges that it is not possible to anticipate every potential failure or contamination scenario, 

but believes that the owner or operator's demonstration of financial responsibility per §146.85 and 

emergency and remedial response plan per §146.94 should address any reasonably conceived failure 

or contamination scenario based on site- and project-specific information. The purpose of these 

requirements is to ensure that in the unlikely event of an emergency, a plan is in place and resources 

are available to expeditiously mitigate the situation. For additional information on the financial 

responsibility and emergency and remedial response requirement for GS projects, see the preamble to 

the final rule and the responses to comments on the proposed GS rule. 

EPA is developing guidance on financial responsibility to assist owners or operators in evaluating the 

requirements of §146.85 and to assist Directors in evaluating financial responsibility demonstrations. 

The guidance describes the types of financial mechanisms that operators may choose to use to meet 

the financial responsibility requirements for GS wells and it will also include a section on how best to 

estimate costs to support accurate financial responsibility demonstrations. This guidance will be 

available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

375
Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28212 

Comment: Additional financial responsibility measures for projects involving waivers do 

not appear to be consistent or well articulated. The NODA states on page 44811 

that "The owner/operator would also demonstrate sufficient, additional financial 

responsibility to address any potential contamination of USDWs above or below 

the injection zone." This is immediately proceeded by a passage that speaks to 

the need to prepare a plan that considers "regional water resources issues and 

has explored alternative water supplies or water treatment options." Later on 

this same page, the prospective CO2 storage operator is asked for a plan "for 

securing alternative resources or treating USDW formation waters in the event of 

contamination related to the Class VI injection activity." These seem to be 

describing wildly different levels of responsibility and financial commitment. 

The requirement to demonstrate existing financial resources needed to provide 

clean water to all possible current and future users within an undefined region 

seems like an activity that could cost millions, hundreds of millions, billions 

of dollars. On the other hand, a plan for how one might secure alternative 

sources of water if the need should ever arise seems like something that could 

be satisfied via a $10,000 paper study. The large gap between these two 

endpoints will likely lead to confusion among CCS stakeholders. The USEPA is 

encouraged to better define what would be expected of applicants for wells that 

would need waivers so that CCS stakeholders can more thoughtfully respond to the 

proposal. 

Individual Response: The requirements at §146.95 for owners and operators seeking injection 

depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for financial responsibility, to ensure that the proposed site is 

evaluated in the context of the presence of USDWs above and below the injection zone. EPA 

anticipates that issuance of waivers will be limited to circumstances where there are deep USDWs 

and/or where the lack of a waiver of injection depth requirements would result in impractical or 

technically infeasible well construction, and where USDW protection is demonstrated and maintained 

through the life of the GS project. 

EPA is developing guidance on financial responsibility to assist owners or operators in evaluating the 

requirements of §146.85 and to assist Directors in evaluating financial responsibility demonstrations. 

EPA is also developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors. These guidances will be 

376
available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Patrick J. Nugent 

Commenter Organization: Texas Pipeline Association (TPA) 

EPA Letter ID: 0340 

EPA Comment ID: 28016 

Comment: 3. The rule's financial assurance requirements are already too stringent and 

should not be made even more onerous. In our December 12, 2008 comments, TPA 

urged EPA to avoid imposition of unduly burdensome financial assurance 

requirements upon those who are engaged in carbon sequestration. We stated our 

belief that the requirement of unduly lengthy financial assurance commitments 

might unnecessarily hinder development and implementation of sequestration 

projects, and we urged that financial assurance requirements be assessed on a 

site-specific, case-by-case basis. We also urged EPA to consider alternative 

arrangements such as group stewardship or designated management entities for the 

post-closure period. 

Given our views as to the possible negative impact that unduly burdensome 

financial assurance requirements might have on companies' willingness to engage 

in geologic sequestration, we are troubled by the NODA's statement that waiver 

participants would be required to supplement standard Class VI permit 

information with a demonstration of "sufficient, additional fmancial 

responsibility to address any potential contamination of USDWs above or below 

the injection zone." 74 Fed. Reg. 44811 (emphasis added). As we believe that the 

financial assurance requirements set forth in the initial notice of rulemaking 

are already too burdensome, we oppose imposition of any additional requirements 

in this area. We again urge EPA to ensure that financial assurance requirements 

are imposed in a manner that does not create an unnecessary burden on program 

participants. Such requirements should be imposed only after an assessment of 

the specific conditions at each particular site. We believe that imposition of 

any additional requirements would be counterproductive, because it would 

discourage the use of geologic sequestration while not adding any real benefit 

to the public. 

377
Individual Response: The requirements at §146.95 for owners and operators seeking injection 

depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for financial responsibility, to ensure that the proposed site is 

evaluated in the context of the presence of USDWs above and below the injection zone. For additional 

information on financial responsibility for GS projects, see the preamble to the final rule and the 

responses to comments on the proposed GS rule.

EPA is developing guidance on financial responsibility to assist owners or operators in evaluating the 

requirements of §146.85 and to assist Directors in evaluating financial responsibility demonstrations. 

EPA is also developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors. These guidances will be 

available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert S. Lynch 

Commenter Organization: Irrigation & Electrical Districts Association of Arizona 

EPA Letter ID: 0372 

EPA Comment ID: 27950 

Comment: Concerning financial responsibility, the notice says that the responsible party 

would have to supplement the emergency remedial response plan otherwise required 

of an underground injection control (UIC) Class VI permit, which otherwise 

requires injection to take place below USDWs. The applicant would have to 

"demonstrate sufficient, additional financial responsibility to address any 

potential contamination of USDWs above or below the injection zone". We have no 

idea what this means. We presume that the demonstration would be to EPA in the 

process for obtaining the waiver. However, the factors that are then listed as 

those that might be considered are just that, things that might be considered, 

not things that must be. Most importantly, because this is a process 

anticipating things going wrong, the listing for a proposed plan "for securing 

alternative resources or treating USDW formations in the event of contamination 

related to Class VI injection activity" gives essentially no detail on what the 

proposed plan would have to be in order to qualify. Will there need to be a 

legal opinion from a qualified water attorney that the applicant has the legal 

ability to acquire such an alternative resource? Has the technical capability 

378
to treat contaminated USDW "formation waters"? What level of contamination 

triggers this requirement? What happens if the contaminated USDW is not being 

used for drinking water purposes at the time of contamination but only for other 

uses such as industrial or agricultural uses? What form will financial 

responsibility have to take? Insurance? Bonding? How much? And how will these 

matters be determined? 

Individual Response: EPA clarifies that the owner or operator must develop and implement an 

emergency and remedial response plan for how any contaminated water or other resources will be 

replaced if an adverse event associated with the GS project renders them unusable per §146.94. The 

owner or operator must demonstrate the financial resources to carry out the plan if it becomes 

necessary 9146.85. EPA will issue guidance on developing the required plans and meeting financial 

responsibility requirements. 

EPA adds that the requirements at §146.95 for owners and operators seeking injection depth waivers 

are intended to add to and modify the requirements that all GS well owners or operators must meet, 

including those for financial responsibility and emergency and remedial response, to ensure that the 

proposed site is evaluated in the context of the presence of USDWs above and below the injection 

zone. 

EPA is developing guidance on financial responsibility to assist owners or operators in evaluating the 

requirements of §146.85 and to assist Directors in evaluating financial responsibility demonstrations. 

EPA is also developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors. These guidances will be

available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27990 

Comment: Comment No. 47 

379
Page 44811 

Issue Topic from EPA's NODA 

The owner/operator would also demonstrate sufficient, additional financial 

responsibility to address any potential contamination of USDWs above or below 

the injection zone. 

Carbon Sequestration Council Comments 

Financial assurance is tied to plans and should not be changed for this waiver 

requirement.There is no appropriate additional basis for addressing "potential 

contamination" beyond what would already be required in preparing and 

maintaining the appropriate required plans. 

Individual Response: The requirements at §146.95 for owners and operators seeking injection 

depth waivers are intended to add to and modify the requirements that all GS well owners or 

operators must meet, including those for financial responsibility, to ensure that the proposed site is 

evaluated in the context of the presence of USDWs above and below the injection zone. 

EPA is developing guidance on financial responsibility to assist owners or operators in evaluating the 

requirements of §146.85 and to assist Directors in evaluating financial responsibility demonstrations. 

EPA is also developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors. These guidances will be 

available on EPA’s website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27994 

Other EPA Comment Codes and Descriptions: 3300 3.3. Comments on Specific Elements of the 

Waiver Approach 

380
Comment: Comment No. 52 

Page 44811 

Issue Topic from EPA's NODA 

- The proposed plan for securing alternative resources or treating USDW 

formation waters in the event of contamination related to the Class VI injection 

activity; and, 

Carbon Sequestration Council Comments 

This is a matter to be addressed on a site-specific basis by the operator as 

part of the emergency response plan. It should not be required in all instances 

and should be a part of the plan only where chosen as an approach by the 

owner/operator to meet the regular permit requirement for preparation and 

maintenance of that plan. 

Individual Response: As described above, the requirements at §146.95 for owners and operators 

seeking injection depth waivers are intended to add to and modify the requirements that all GS well 

owners or operators must meet, including those for financial responsibility and emergency and 

remedial response, to ensure that the proposed site is evaluated in the context of the presence of 

USDWs above and below the injection zone. 

EPA clarifies that, for GS projects where injection depth waivers are sought, the Director must also 

consider the proposed emergency and remedial response plan in making a determination whether to 

grant a waiver per §146.95(b)(1)(iv). EPA believes that additional consideration of the emergency and 

remedial response plan, which is required of all owners or operators per §146.94, in the context of 

USDWs above and below the injection zone is appropriate where injection depth waivers are being 

considered. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

381
EPA Letter ID: 0383 

EPA Comment ID: 28110 

Comment: - Long-term financial responsibility (> 50 years) must be assigned to ensure the 

viability of current and future water supplies that could be negatively impacted 

by a GS project. The contaminating party must not be allowed to walk away. 

Individual Response: Under the final GS rule, once an owner or operator has met all regulatory 

requirements under Part 146 for Class VI wells and the Director has approved site closure pursuant to 

requirements at §146.93, the owner or operator will generally no longer be subject to enforcement for 

regulatory noncompliance. Furthermore, their financial instrument as required under §146.85 will be 

released if it was not used. However, even if a site closure is approved under §146.93, an owner or 

operator may be held liable for regulatory noncompliance (including violation of 40 CFR 144.12) in 

certain circumstances. For example, an owner or operator may be held liable for regulatory 

noncompliance even after site closure was approved if the Director relied on erroneous information 

(e.g., erroneous modeling data) provided by the owner or operator when approving site closure. 

Separate from EPA’s authority to enforce regulatory compliance, an owner or operator may be subject 

to a §1431 response order even after proper site closure is approved under §146.93. Under §1431 the 

Administrator may require an owner or operator to take necessary response measures if he or she 

receives information that a contaminant is present or is likely to enter a public water system or an 

USDW, which may present an imminent and substantial endangerment to the health of persons, and 

the appropriate State and local authorities have not acted to protect the health of such persons. The 

action may include issuing administrative orders or commencing a civil action for appropriate relief 

against the owner or operator of a Class VI well. If the owner or operator fails to comply with the 

order, they may be subject to a civil penalty for each day in which such violation occurs or failure to 

comply continues. 

Furthermore, after site closure an owner or operator may remain liable under tort and other remedies, 

or under other federal statutes including, but not limited to, Clean Air Act, 42 U.S.C. §§ 7401-7671; 

CERCLA, 42 U.S.C. § 9601-9675; and RCRA, 42 U.S.C. § 6901-6992. Please note that EPA does not 

have authority to transfer SDWA or other legal liability for Class VI wells to the State or federal 

government or a third-party fund. 

For additional information on the financial responsibility requirements for GS projects, see the 

preamble to the final rule and the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 163 to 165, which is an excerpt from a previous 

382
section, lines 154 to 166. This comment appears twice in this report, once for each set of line 

numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3350 3.3.5. Requirement to Submit Waiver Application to UIC and PWSS 

Program Directors 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 27873 

Comment: The inclusion of the Public Water Supply Supervision (PWSS) Program Director in 

the decision process adds an additional layer of bureaucracy, is duplicative, 

and is inefficient. Final decision authority must be with the agency granted 

primacy for regulation of CO2 sequestration. EPA must not dictate to states 

that have primacy which agencies must approve an application. The PWSS Program 

Director can have input and participate through the normal public participation 

process. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this consultation be documented to ensure transparent public disclosure 

of all information evaluated by the Directors and their respective recommendations. EPA clarifies that 

the PWSS director does not have "veto power" over a UIC permitting decision; instead, the role of the 

PWSS Director is to ensure consideration of water system and water resource issues where injection 

into non-USDW formations above the lowermost USDW is being considered. Due to the unique nature 

383
of the injection depth waiver process and in an effort to ensure national consistency and application of 

the requirements, the requirement at §146.95(d) indicates that the Regional Administrator makes the 

final determination regarding waiver issuance following an evaluation of all site-specific information, 

public notice, and recommendations from the UIC Director. EPA believes that UIC Program staff is in 

the appropriate position to evaluate the technical details of the waiver application, in concert with the 

UIC permit application, to inform the Regional Administrator’s decision. EPA adds that adoption of the 

waiver process will remain at the discretion of individual UIC programs. 

EPA believes that the consultative communication between the UIC Director and PWSS Directors will 

enable a comprehensive evaluation of resource concerns and increase USDW protection. EPA adds that 

it does not anticipate that the PWSS director would perform the same level of review as the UIC 

Director and anticipates states would determine the level of PWSS review. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28046 

Comment: Second, for the waiver system to work effectively, the final decision making 

authority for a waiver should be with the agency holding primacy for the 

proposed Class VI UIC program. EPA's current proposal would appear to give a 

Public Water Supply Supervision (PWSS) Program Director veto power over a 

waiver. API believes this is not appropriate because a PWSS Program Director 

(and the Director's staff) is rarely as knowledgeable regarding underground 

injection as the UIC Program Director (and the Director's staff). The PWSS 

director should participate with a commenting role in the waiver process as 

opposed to being the decision making authority. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all States, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this consultation be documented to ensure transparent public disclosure 

of all information evaluated by the Directors and their respective recommendations. EPA clarifies that 

384
the PWSS director does not have "veto power" over a UIC permitting decision; instead, the role of the 

PWSS Director is to ensure consideration of water system and water resource issues where injection 

into non-USDW formations above the lowermost USDW is being considered. Due to the unique nature 

of the injection depth waiver process and in an effort to ensure national consistency and application of 

the requirements, the requirement at §146.95(d) indicates that the Regional Administrator makes the 

final determination regarding waiver issuance following an evaluation of all site-specific information, 

public notice, and recommendations from the UIC Director. EPA believes that UIC Program staff is in 

the appropriate position to evaluate the technical details of the waiver application, in concert with the 

UIC permit application, to inform the Regional Administrator’s decision. EPA adds that adoption of the 

waiver process will remain at the discretion of individual UIC programs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

EPA Letter ID: 0369 

EPA Comment ID: 27943 

Comment: -EPA indicates that the "Public Water Supply Supervision (PWSS) Director," in 

conjunction with the UIC Program Director, must review and approve waivers for 

injection depths above the lowest USDW formation. However, EPA does not define 

who the PWSS Director is, but presumably it is the head of the State, 

Territorial, or Tribal Drinking Water Primacy Agency, which may be the EPA 

Regional Administrator (who can also be the UIC Program Director). EPA needs to 

define the position of DWSS Director and determine whether an EPA Regional 

Administrator can fill both roles without a conflict of interest. 

Individual Response: EPA clarifies that the PWSS Director is the person who has charge of the 

program administering the PWSS portion of drinking water regulations in any states, Territories, or 

Tribes within the AoR of the GS well. The final GS rule includes a requirement that the UIC Program 

Director consult with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within 

the AoR of a well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process 

is necessary and appropriate to ensure that water system concerns are considered when evaluating a 

waiver application. EPA requires that this information be documented to ensure that this consultation 

will enable transparent public disclosure of all information evaluated by the Directors and their 

respective recommendations. EPA clarifies that the PWSS director does not have "veto power" over a 

385
UIC permitting decision; instead, the role of the PWSS Director is to ensure consideration of water 

system and water resource issues where injection into non-USDW formations above the lowermost 

USDW is being considered. EPA believes that UIC Program staff are in the appropriate position to 

evaluate the technical details of the waiver application, in concert with the UIC permit application, and 

the final requirements retain decision making authority with the UIC Program. 

While EPA disagrees that the EPA Regional Administrator will fill both of these roles, EPA clarifies that 

the Regional Administrator will provide written concurrence or non-concurrence regarding whether to 

issue an injection depth waiver per §146.95(d). EPA adds that the final determination regarding 

waiver issuance will be made by the Director, following evaluation of all site-specific information, 

public notice, and receipt of written concurrence or non-concurrence from the Regional Administrator. 

EPA believes Agency input is necessary in making injection depth waiver decisions and agrees with 

commenters who expressed interest in ensuring that multi-state boundary and water resource issues 

are addressed. The Agency also believes that Agency involvement in the waiver decision process will 

contribute to national consistency in waiver issuance.

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28019 

Comment: 1. The NODA proposes that PWSS Directors play a formal role in the approval or 

disapproval of applications to inject above the lowermost USDW. The committee 

would like to point out several issues related to such an approval requirement: 

a. PWSS Directors and their staffs that are not already a part of the state UIC 

primacy agency are less likely to have the requisite UIC permitting and 

technical expertise needed to perform such a review. Consequently, such PWSS 

agencies would need to hire additional staff and acquire appropriate training 

386
for the staff. Further, in order for such PWSS Directors to be a formal part of 

the review process states may need to revise their statutes to provide 

authority to the PWSS agency. These are additional burdens on the states that do 

not substantially "add value" to the permitting or operation of geosequestration 

projects; 

b. No additional criteria for PWSS agency review has been suggested that would 

not already be part of the state UIC primacy agency’s review process. Again 

there is no "value added" element to requiring this additional review. 

c. The determination as to which elements of state government play a formal or 

authoritative role in the review and approval of activities that are part of a 

state primacy program should rest with the state alone. States are the best 

judge of which agency should perform permitting functions; 

d. Any requirement that would provide for two separate agencies of state 

government to have the same authority over a single permitting process is 

inefficient and duplicative. In Wyoming’s case, it would result in both a 

federal and state agency having the same authority, since Region 8 administers 

the PWSS rather than the state. It is also conceivable that the UIC primacy 

agency may approve or disapprove an application while the PWSS Director may take 

an opposite stance. Consequently, the effect of the waiver process would be to 

create a veto authority for one state agency over the actions of another state 

agency. In such cases, one state agency could be placed in the position of 

initiating an administrative action against another state agency or at least 

testifying against another agency in any action initiated by an aggrieved party 

under state administrative adjudication laws. Therefore, in the interests of 

"good government", a single state agency should have the final authority to 

approve or deny an application. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this consultation be documented to ensure transparent public disclosure 

of all information evaluated by the Directors and their respective recommendations. EPA clarifies that 

the PWSS director does not have "veto power" over a UIC permitting decision; instead, the role of the 

PWSS Director is to ensure consideration of water system and water resource issues where injection 

into non-USDW formations above the lowermost USDW is being considered. Due to the unique nature 

of the injection depth waiver process and in an effort to ensure national consistency and application of 

387
the requirements, the requirement at §146.95(d) indicates that the Regional Administrator makes the 

final determination regarding waiver issuance following an evaluation of all site-specific information, 

public notice, and recommendations from the UIC Director. EPA believes that UIC Program staff is in 

the appropriate position to evaluate the technical details of the waiver application, in concert with the 

UIC permit application, to inform the Regional Administrator’s decision. EPA adds that adoption of the 

waiver process will remain at the discretion of individual UIC programs. 

EPA disagrees that consultation with the PWSS Director would be "burdensome," "inefficient," or 

"duplicative," and believes that the consultative communication between the UIC Director and PWSS 

Directors will enable a comprehensive evaluation of resource concerns and increase USDW protection 

EPA adds that it does not anticipate that the PWSS director would perform the same level of review as 

the UIC Director and anticipates states would determine the level of PWSS review. 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm.

EPA clarifies that adoption of the waiver process remains at the discretion of individual UIC programs. 

Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are not required to 

provide for injection depth waivers in their UIC regulations and may choose not to make this process 

available to Class VI wells under their jurisdiction. Although some commenters asked EPA to require 

that waivers be applied nationally, the Agency believes that the decision about whether a waiver 

program is appropriate in a specific State, Tribe, or Territory should be made by each program. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28022 

Comment: The GWPC CO2 Committee recommends the following with respect to implementation of 

a waiver process: 

1. The authority for granting a waiver should rest solely with the state UIC 

388
primacy agency. 

Individual Response: EPA clarifies that the final determination regarding waiver issuance will be 

made by the Director, following evaluation of all site-specific information, public notice, and receipt of 

written concurrence or non-concurrence from the Regional Administrator. The role of the PWSS 

Director is to ensure consideration of water system and water resource issues where injection into 

non-USDW formations above the lowermost USDW is being considered. 

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

The final GS rule includes a requirement that the UIC Program Director consult with the PWSS 

Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a well for which a 

waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary and appropriate 

to ensure that water system concerns are considered when evaluating a waiver application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28112 

Comment: 3. In those cases where the PWSS Director is not a part of the state UIC primacy 

agency, a special notification with opportunity to comment should be provided to 

the PWSS Director. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

389
and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this information be documented to ensure that this consultation will 

enable transparent public disclosure of all information evaluated by the Directors and their respective 

recommendations. 

EPA believes this process is necessary and appropriate to ensure that water system concerns are 

considered when evaluating a waiver application. EPA clarifies that the final determination regarding 

waiver issuance will be made by the Director, following evaluation of all site-specific information, 

public notice, and receipt of written concurrence or non-concurrence from the Regional Administrator. 

EPA believes that UIC Program staff are in the appropriate position to evaluate the technical details of 

the waiver application, in concert with the UIC permit application, and the final requirements retain 

decision making authority with the UIC Program. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Smith 

Commenter Organization: Questar Exploration & Production Company 

EPA Letter ID: 0374 

EPA Comment ID: 28119 

Comment: in practice. Including the Public Water Supply Supervision (PWSS) Program 

Director in the approval process, like many of the underlying proposed 

regulations, is unnecessary and only has the potential of slowing down the 

implementation of GS in appropriate areas. Along those lines, Questar wishes to 

Individual Response: EPA believes the consultation with the PWSS Director process is necessary and 

appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. The final GS rule includes a requirement that the UIC Program Director consult with the 

PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a well for 

which a waiver is sought as specified in §146.95(b)(2). EPA clarifies that the communication with the 

PWSS Director is consultative and does not constitute a final decision making. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

390
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Stan Belieu 

Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC) 

EPA Letter ID: 0378 

EPA Comment ID: 28183 

Comment: proposed Class VI UIC program. In Nebraska, UIC primacy lays with NDEQ and 

NOGCC, any requirement that would provide for non-UIC delegated programs to have 

the same authority over a single permitting process is inefficient and 

duplicative. EPA’s current proposal would appear to give the Public Water Supply 

Supervision (PWSS) Program Director essentially veto power over the waiver. 

NOGCC feels this is not appropriate due to the fact that the PWSS Program 

Director is not as knowledgeable regarding underground injection does not have 

the technical expertise as the UIC Program Director. In addition, NOGCC would 

question what authority the EPA has to dictate to those states with primacy 

which agencies must approve a permit. Instead, APC would recommend that the 

PWSS, like all other interested agencies, be included in the comment period 

making sure that they have the opportunity to raise any concerns they may have 

with the project. 

Individual Response: EPA disagrees that consultation with the PWSS Director is duplicative: the 

communication with the PWSS Director is consultative and does not constitute a final decision making. 

The final GS rule includes a requirement that the UIC Program Director consult with the PWSS 

Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a well for which a 

waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary and appropriate 

to ensure that water system concerns are considered when evaluating a waiver application. 

EPA clarifies that the PWSS director does not have "veto power" over a UIC permitting decision; 

instead, the role of the PWSS Director is to ensure consideration of water system and water resource 

issues where injection into non-USDW formations above the lowermost USDW is being considered. 

EPA clarifies that the final determination regarding waiver issuance will be made by the Director, 

following evaluation of all site-specific information, public notice, and receipt of written concurrence or 

non-concurrence from the Regional Administrator. EPA believes that UIC Program staff are in the 

appropriate position to evaluate the technical details of the waiver application, in concert with the UIC 

permit application, and the final requirements retain decision-making authority with the UIC Program. 

EPA adds that adoption of the waiver process will remain at the discretion of individual UIC programs, 

and states can opt to not adopt the waiver process if this is deemed too burdensome. 

EPA Team Member: 

391
Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28093 

Comment: Second, for the waiver system to work effectively, the final decision making 

authority for a waiver should be with the agency holding primacy for the 

proposed Class VI UIC program. Any requirement that would provide for two 

separate agencies of state government to have the same authority over a single 

permitting process is inefficient and unnecessarily duplicative creating a risk 

of inconsistent permitting decisions. EPA’s current proposal would appear to 

give the Public Water Supply Supervision (PWSS) Program Director essentially 

veto power over the waiver. APC feels this is not appropriate due to the fact 

that the PWSS Program Director (and the Director’s staff) is not as 

knowledgeable regarding underground injection as the UIC Program Director (and 

the Director’s staff). In addition, APC questions what authority the EPA has to 

dictate to those states with primacy which agencies must approve a permit. 

Instead, APC recommends that the PWSS, like all other interested agencies, be 

included in the comment period making sure that they have the opportunity to 

raise any concerns they may have with the project. 

Individual Response: EPA disagrees that consultation with the PWSS Director is duplicative: the 

communication with the PWSS Director is consultative and does not constitute a final decision making. 

The final GS rule includes a requirement that the UIC Program Director consult with the PWSS 

Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a well for which a 

waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary and appropriate 

to ensure that water system concerns are considered when evaluating a waiver application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

392
Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27983 

Comment: Comment No. 40 

Page 44810 

Issue Topic from EPA's NODA 

The alternative EPA is considering relies on the principle of site-suitability 

for GS: injection zones/formations that have suitable upper and lower confining 

units, appropriate lateral and vertical extent to receive and contain the 

injected CO2, and an appropriate management scheme to ensure that the water and 

other resources contained within the injection zone will not be needed in the 

future. The management scheme will also ensure that there is a strategy 

developed to address future needs to access formations below the injection zone. 

Carbon Sequestration Council Comments 

We support the provision to allow CO2 injection into formations above the 

lowermost USDW when adequate containment of injected CO2 and protection of USDWs 

can be demonstrated. As noted in our comments of December 24, 2008, we would 

prefer to have the necessary criteria for GS project siting and containment 

demonstration built into the normal permitting process, where these requirements 

would be routinely applicable whenever a permit applicant is proposing to inject 

into a saline formation that is above the lowermost USDW. The permitting process 

- with the notice, comment, hearing and permitting provisions we support - would 

provide adequately for consideration of the necessary technical issues. 

Nevertheless, we also believe that the concept of a site-specific waiver process 

for geologic storage above the lowermost USDW can be made workable but requires 

some improvements which are specifically noted in these Comments. 

We are concerned in particular that EPA may lack the authority to require a 

waiver process as specifically presented in the NODA because the decisionmaking 

authority that EPA appears to be proposing for PWSS Directors lacks a 

decisionmaking standard that is consistent with the existing statutory 

requirements of the SDWA and EPA's UIC regulations; assigning such a role to 

PWSS Directors would encroach upon the prerogatives of the states under the UIC 

primacy program in violation of the UIC regulations; and division of authority 

393
between UIC Directors and PWSS Directors would be burdensome, inefficient, and 

potentially disruptive if the Directors disagree on approvals. 

Individual Response: EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will 

make the final determination whether to issue an injection depth waiver. However, prior to a final 

decision, the Director must provide the Regional Administrator with the information collected during 

the waiver application and the public notice processes. Based on this information and pursuant to 

requirements at §146.95(d), the Regional Administrator will provide written concurrence or nonconcurrence regarding waiver issuance. The Agency clarifies that these requirements are within the 

authority of the Safe Drinking Water Act. 

The final GS rule includes a requirement that the UIC Program Director consult with the PWSS 

Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a well for which a 

waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary and appropriate 

to ensure that water system concerns are considered when evaluating a waiver application. EPA 

requires that this consultation be documented to ensure transparent public disclosure of all 

information evaluated by the Directors and their respective recommendations. EPA clarifies that the 

PWSS director does not have "veto power" over a UIC permitting decision; instead, the role of the 

PWSS Director is to ensure consideration of water system and water resource issues where injection 

into non-USDW formations above the lowermost USDW is being considered. Due to the unique nature 

of the injection depth waiver process and in an effort to ensure national consistency and application of 

the requirements, the requirement at §146.95(d) indicates that the Regional Administrator makes the 

final determination regarding waiver issuance following an evaluation of all site-specific information, 

public notice, and recommendations from the UIC Director. EPA believes that UIC Program staff is in 

the appropriate position to evaluate the technical details of the waiver application, in concert with the 

UIC permit application, to inform the Regional Administrator’s decision. EPA adds that adoption of the 

waiver process will remain at the discretion of individual UIC programs. 

EPA disagrees that consultation with the PWSS Director would be "burdensome," "inefficient," or 

"duplicative," and believes that the consultative communication between the UIC Director and PWSS 

Directors will enable a comprehensive evaluation of resource concerns and increase USDW protection. 

EPA adds that it does not anticipate that the PWSS director would perform the same level of review as 

the UIC Director and anticipates states would determine the level of PWSS review. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

394
Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27991 

Comment: Comment No. 48 

Page 44811 

Issue Topic from EPA's NODA 

Upon compliance with the waiver process requirements, the owner/operator would 

need to submit the information jointly to the UIC Program Director and the PWSS 

Program Director. 

Carbon Sequestration Council Comments 

The language in this statement may be creating unnecessary confusion. If the 

intent is to provide for notice to the PWSS Program Director so that appropriate 

comments can be submitted to the UIC Program Director for consideration in 

preparing and approving a permit, that would be acceptable. The statements 

here, however, suggest that there would be shared decisionmaking between the two 

Directors, which would be inefficient and could lead to conflicts among the 

agencies. Moreover, this type of approach would not be legal under the 

provisions of the SDWA and 40 CFR Part 145, which allow states to identify the 

agencies to participate in UIC permitting and to provide how the 

responsibilities will be divided among the participating state agencies. 40 CFR 

145.23(b). The authority for granting a waiver should rest solely with the 

state UIC primacy agency. 

Individual Response: EPA clarifies that decision making regarding injection depth waivers will not be 

shared and disagrees that consultation with the PWSS Director is duplicative. The communication with 

the PWSS Director is consultative and does not constitute a final decision making. The final GS rule 

includes a requirement that the UIC Program Director consult with the PWSS Directors of all states, 

Territories, and Tribes having jurisdiction within the AoR of a well for which a waiver is sought as 

specified in §146.95(b)(2). EPA believes this process is necessary and appropriate to ensure that 

water system concerns are considered when evaluating a waiver application. 

EPA clarifies that the role of the PWSS Director is to ensure consideration of water system and water 

resource issues where injection into non-USDW formations above the lowermost USDW is being 

395
considered. Due to the unique nature of the injection depth waiver process and in an effort to ensure 

national consistency and application of the requirements, the requirement at §146.95(d) indicates that 

the Regional Administrator makes the final determination regarding waiver issuance following an 

evaluation of all site-specific information, public notice, and recommendations from the UIC Director. 

EPA believes that UIC Program staff is in the appropriate position to evaluate the technical details of 

the waiver application, in concert with the UIC permit application, to inform the Regional 

Administrator’s decision. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27993 

Other EPA Comment Codes and Descriptions: 3300 3.3. Comments on Specific Elements of the 

Waiver Approach 

Comment: Comment No. 50 

Page 44811 

Issue Topic from EPA's NODA 

- Planned needs, potential and/or future use of USDWs and non- USDWs in the 

area; 

Carbon Sequestration Council Comments 

Concrete plans for future use of formations can and should be submitted to EPA 

in comments from the PWSS Director for consideration but must be considered 

within the context of the SDWA endangerment standard for protecting USDWs. 

Comment No. 51 

Page 44811 

Issue Topic from EPA's NODA 

396
- Planned (or permitted) water, hydrocarbon, or mineral resource exploitation 

potential of the proposed injection formation and other formations both above 

and below the injection zone - to determine if there are any plans to drill 

through the formation to access resources in or beneath the proposed injection 

zone/formation; 

Carbon Sequestration Council Comments 

Same comment as 50 above. 

Individual Response: EPA agrees that information on planned and future uses of USDWs and water 

and mineral resources near an injection zone should be considered by the UIC and PWSS program 

staff in the context of USDW protection, and believes that the final GS rule requirements for 

consultation allow consideration from both perspectives. 

EPA believes that the requirements at §146.95 for owners and operators seeking injection depth 

waivers are intended to add to and modify the requirements that all GS well owners or operators must 

meet to ensure that the proposed site is evaluated in the context of the presence of USDWs above and 

below the injection zone. 

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27996 

Other EPA Comment Codes and Descriptions: 3370 3.3.7. Notice and Hearing 

397
Comment: Comment No. 54 

Page 44811 

Issue Topic from EPA's NODA 

The waiver may also be subject to local notice and public hearing. Following a 

public hearing and waiver approval by both Program Directors, the owner/operator 

may complete and submit the Class VI permit application. 

Carbon Sequestration Council Comments 

The authority for granting a waiver should rest solely with the state UIC 

primacy agency. It would, however, seem appropriate to provide a special 

notification to the PWSS Director with opportunity to comment. 

Individual Response: EPA believes that informing and consulting with the PWSS Directors of all 

states, Territories, and Tribes having jurisdiction within the AoR of a well for which a waiver is sought 

as specified in §146.95(b)(2) is necessary and appropriate to ensure that water system concerns are 

considered when evaluating a waiver application. EPA requires that this consultation be documented to 

ensure transparent public disclosure of all information evaluated by the Directors and their respective 

recommendations. 

EPA clarifies that the final determination regarding waiver issuance will be made by the Director, 

following evaluation of all site-specific information, public notice, and receipt of written concurrence or 

non-concurrence from the Regional Administrator. EPA believes Agency input is necessary in making 

injection depth waiver decisions and agrees with commenters who expressed interest in ensuring that 

multi-state boundary and water resource issues are addressed. The Agency also believes that Agency 

involvement in the waiver decision process will contribute to national consistency in waiver issuance. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28132 

398
Comment: As proposed, the waiver process would require applicants to submit additional 

information to the UIC program director and Public Water Supply Supervision 

(PWSS) program director for review prior to completion of the permit 

application, and these directors would weigh this information against specified 

factors in making waiver decisions. In drafting a final rule, EPA should strive 

to develop clear guidelines for decision makers in evaluating waiver 

applications as well as the development of a transparent and, to the extent 

possible, outcome-predictable process to provide guidance for future applicants. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28159 

Comment: Comment: Requirement that the waiver be approved by both the UIC Program 

Director and the PWSS Program Director 

We believe this requirement is unnecessary since the focus of the UIC program is 

upon assessing permit applications and issuing permits to ensure the protection 

of USDWs, whether they be used as public water supply sources, or not. That is 

the primary purpose of the UIC program review. To engage another program (PWSS) 

in the same review and approval process would essentially be a redundant, 

399
duplicative effort with questionable, if any value added. In addition, it has 

the potential to pit the determinations of one agency against another. 

We believe this requirement is further problematic, and especially for states 

where the respective UIC and PWSS Program Directors may be operating within 

different agencies under different statutory authorities and/or regulatory 

requirements. We would like to point out that such a requirement presents 

numerous, unpredictable consequences in those situations where Directors may 

disagree on the approval of the waiver. As you know, many states have 

administrative procedures and review/appeal boards that are unique to their 

agency, but could work at cross-purposes in the event there was disagreement 

between Directors on the waiver approval. For instance, if each Director reports 

to his/her own administrative hearing board, or council, for decisions on 

appeal, which board/council decision prevails when both have equal authority? 

Such an arrangement places both the waiver applicant and the agencies in a realm 

of great uncertainty and delay in determining the status of the waiver 

application. The requirement is especially problematic for Wyoming, the only 

state where US EPA [Region 8] administers the PWSS Program, rather than the 

state. Under the proposed scenario, final waiver approval would require both 

state and federal approval, resulting in confusion regarding the highest 

determinations of state and federal sovereignty and rights. 

Finally, we caution that the Safe Drinking Water Act may not provide specific 

authority for PWSS programs to engage in permit, or waiver decisions, regarding 

the protection of USDWs from underground injection. To the contrary, the SDWA 

contains no requirements to implement drinking water protection programs such as 

Wellhead or Source Water protection programs. To extend PWSS programs into the 

review of UIC program administrative decisions, waivers, and permits may be 

questionable from a legal standpoint, but unnecessary, regardless. 

We remain sensitive, however, to the interests of local public water systems in 

being aware of activities within their wellhead and/or source water protection 

areas that may have the potential to affect the quality or quantity of source 

waters supplying their systems. 

Recommendation: We recommend that there be no requirement for the PWSS Program 

Director to approve the waiver; the approval determination should be left solely 

with the UIC Program Director. In order to ensure that the PWSS Program Director 

and local public water systems that may potentially be affected by a GS project 

are informed that a waiver application has been applied for, we would suggest 

that US EPA consider specifying in the proposed GS rule that public notice be 

400
provided to those entities. In addition, US EPA may wish to consider requiring 

that state approved Wellhead and Source Water Protection areas be included in 

those items to be illustrated on the map required under §146.82 of the proposed 

GS rule. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this consultation be documented to ensure transparent public disclosure 

of all information evaluated by the Directors and their respective recommendations. 

EPA clarifies that the PWSS director does not have "veto power" over a UIC permitting decision; 

instead, the role of the PWSS Director is to ensure consideration of water system and water resource 

issues where injection into non-USDW formations above the lowermost USDW is being considered. 

Due to the unique nature of the injection depth waiver process and in an effort to ensure national 

consistency and application of the requirements, the requirement at §146.95(d) indicates that the 

Regional Administrator makes the final determination regarding waiver issuance following an 

evaluation of all site-specific information, public notice, and recommendations from the UIC Director. 

EPA believes that UIC Program staff is in the appropriate position to evaluate the technical details of 

the waiver application, in concert with the UIC permit application, to inform the Regional 

Administrator’s decision. EPA adds that adoption of the waiver process will remain at the discretion of 

individual UIC programs. 

EPA is developing guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James Taft 

Commenter Organization: Association of State Drinking Water Administrators (ASDWA) 

EPA Letter ID: 0392 

EPA Comment ID: 28757 

401
Comment: In particular, ASDWA is offering comments on the portion of the NODA proposal 

suggesting that state drinking water program directors play a formal role in the 

approval or disapproval of applications to inject CO2 into formations above the 

lowermost underground source of drinking water (USDW). While ASDWA believes that 

state Public Water Supply Supervision (PWSS) programs should be consulted during 

the subject waiver request process, we believe that a joint permitting function 

could be problematic. As an alternative, ASDWA recommends the Underground 

Injection Control (UIC) primacy agency be required to notify the director of the 

state water resource management and PWSS agency(ies) and that they be provided 

the opportunity to offer comments on the proposed action. 

A single state agency should have the final authority to approve or deny an 

application. Providing two separate agencies of state government the same 

authority over a single permitting process is potentially inefficient and 

duplicative. It would also create the potential for one agency to approve an 

application while the other proposes denial. 

PWSS Directors and their staffs are less likely to have the requisite UIC 

permitting and technical expertise needed to perform such a review. 

Consequently, such PWSS agencies would need to hire additional staff and acquire 

appropriate training for the staff. This would require an additional source of 

dedicated funding, since state PWSS programs are already severely underfunded. 

Further, in order for such PWSS Directors to be a formal part of the review 

process, states may need to revise their statutes to provide the necessary 

authority to the PWSS agency. 

I light of the foregoing considerations, ASDWA believes a single state agency 

should approve or disapprove the subject applications - with a requirement for 

notification and comment by the water resource management and PWSS agencies. 

Individual Response: The final GS rule includes a requirement that the UIC Program Director consult 

with the PWSS Directors of all states, Territories, and Tribes having jurisdiction within the AoR of a 

well for which a waiver is sought as specified in §146.95(b)(2). EPA believes this process is necessary 

and appropriate to ensure that water system concerns are considered when evaluating a waiver 

application. EPA requires that this consultation be documented to ensure transparent public disclosure 

of all information evaluated by the Directors and their respective recommendations. EPA clarifies that 

the PWSS director does not have "veto power" over a UIC permitting decision; instead, the role of the 

PWSS Director is to ensure consideration of water system and water resource issues where injection 

into non-USDW formations above the lowermost USDW is being considered. Due to the unique nature 

of the injection depth waiver process and in an effort to ensure national consistency and application of

402
the requirements, the requirement at §146.95(d) indicates that the Regional Administrator makes the 

final determination regarding waiver issuance following an evaluation of all site-specific information, 

public notice, and recommendations from the UIC Director. EPA believes that UIC Program staff is in 

the appropriate position to evaluate the technical details of the waiver application, in concert with the 

UIC permit application, to inform the Regional Administrator’s decision. EPA adds that adoption of the 

waiver process will remain at the discretion of individual UIC programs. 

EPA believes that the consultative communication between the UIC Director and PWSS Directors will 

enable a comprehensive evaluation of resource concerns and increase USDW protection. EPA adds that 

it does not anticipate that the PWSS director would perform the same level of review as the UIC 

Director and anticipates states would determine the level of PWSS review.

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 18-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3360 3.3.6. Requirement to Apply for Waiver Separately from UIC Permit 

Application (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Nightingale 

Commenter Organization: Illinois Environmental Protection Agency (IEPA) 

403
EPA Letter ID: 0333 

EPA Comment ID: 28201 

Other EPA Comment Codes and Descriptions: 3390 3.3.9. Comments Regarding State Discretion 

to Adopt the Waiver Approach 

Comment: III. Consideration of New Approach (pg 44810- 44812) 

Beginning on p. 44810, under the heading "Consideration of New Approach," and 

through p. 44812, the Illinois EPA would like to comment on the proposed waiver 

approach. If a facility wanted to inject above or between USDWs, the proposed 

waiver approach would unduly burden the State UIC program by requiring the 

states to determine site suitability and appropriate injection depth. The State 

of Illinois is in a financial situation in which we have very limited resources 

for the evaluations required under the proposed waiver process. The Illinois EPA 

anticipates that within the next year we will lose more resources due to 

financial restraints. Additionally, there has been no guidance provided as to 

how to accurately evaluate these sites to make a determination on injection 

depths. Therefore, we recommend that U.S. EPA Region V evaluate all the waivers 

that may be requested under these proposed Class VI rules. The U.S. EPA would 

need to provide more funding to the State programs if the waiver approach is 

approved and the additional burden placed on the State regulators. The U.S. EPA 

does not provide enough funding to the State programs to even support the 

current UIC programs. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. 

EPA is developing a series of guidance documents to support Class VI owners and operators and 

Directors including guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

404
EPA Team Member: 

Draft Status: 

Date Uploaded: 24-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28047 

Comment: Third, EPA should integrate the waiver process into the normal permit approval 

process as much as possible. For example, EPA should combine the public hearing 

for the waiver along with the public hearing for the permit, if one is held. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

405
requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28052 

Comment: API supports the waiver approach for dealing with injection above the lowermost 

USDW, but is very concerned that the current administrative arrangement may 

limit its value in facilitating GS. API remains concerned with EPA's proposed 

Individual Response: EPA believes that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

406
USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 05-OCT-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28023 

Comment: 2. The waiver, permit application and aquifer exemption request (if needed) 

should all be part of the same application process such that each is not subject 

to separate public notice and participation requirements. Further, EPA should 

consider accepting state public notification as a means of satisfying federal 

public notice requirements for aquifer exemptions. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

407
notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27977 

Comment: Comment No. 34 

Page 44810 

Issue Topic from EPA's NODA 

EPA believes that a waiver process may respond to the range of comments, both 

for and against the proposed requirement that Class VI wells inject below the 

lowermost USDW. 

Carbon Sequestration Council Comments 

EPA should integrate the waiver process into the normal permit approval process 

as much as possible, for example, by combining the public hearing for the waiver 

with the public hearing for the permit, if one is held. Hearings should be an 

option, and not an automatic requirement. Hearings should be offered as a 

potential option but should not be required unless warranted in the judgment of 

the Director. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

408
proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27984 

Comment: Comment No. 41 

Page 44810 

Issue Topic from EPA's NODA 

EPA is weighing the fact that this alternative would be a divergence from the 

existing UIC deep-well injection requirements for industrial and hazardous waste 

409
injection. It will result in greater injection depth variability throughout the 

United States and may result in emplacement of fluids by injection in closer 

proximity to USDWs than would occur under the proposed requirements. 

Additionally, adoption of this alternative could potentially add a new 

administrative burden to UIC programs pursuing the waiver approach. 

Carbon Sequestration Council Comments 

Divergence from deep well injection requirements for industrial and hazardous 

wastes is completely justified because GS does not involve waste disposal or 

pose the same risk profiles. Moreover, this limitation on waste injection was 

an original part of the UIC program and, as has been noted in comments on the GS 

proposal, is not warranted in all instances for waste disposal. Restrictions 

such as this one run counter to EPA's avowed commitments to performance based 

and adaptable requirements. Instead of identifying and applying the proper 

siting and containment criteria, EPA would be imposing a requirement that 

commenters have already shown to be unwarranted in every instance. The 

administrative burdens to which EPA alludes could be avoided by incorporating 

the consideration of appropriate requirements for injection above the lowermost 

USDW into the normal permitting process rather than in a separate waiver 

process. The burdens also can be minimized by integrating the consideration of 

these criteria as closely as possible with the GS UIC permitting process and 

minimizing the amount of duplicative reviews that are required to be conducted 

by separate agencies at the state and/or EPA regional levels. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems. 

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. The Agency believes that this report 

and requirements at §146.95 are complementary and not redundant of the Class VI permit application 

410
requirements. Furthermore, to eliminate concerns about duplication or redundancy, the requirements 

at §146.82(d) clarify that the supplemental report is not part of the permit application.

Furthermore, EPA believes that the requirements at §146.95 address potential risks associated with 

injection into non-USDW formations above the lowermost USDW. These may include the risk of 

downward migration of fluids if there is no lower confining layer or inadequate confinement. In 

addition, there is the potential that wells will be drilled through the injection zone in the future to 

reach the USDW. EPA believes that the additional requirements that apply to owners or operators of 

Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide additional 

considerations for owners or operators and Directors when permitting such wells to ensure protection 

of all USDWs.

For additional information on EPA's flexible regulatory approach, see the preamble to the final rule and 

the responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27985 

Comment: Comment No. 42 

Page 44810 

Issue Topic from EPA's NODA 

The owner or operator would be required to demonstrate to regulatory authorities 

that such injection can be undertaken and completed in a manner that prevents 

fluid movement into overlying (and underlying) USDWs, thereby preventing the 

endangerment of public health from USDW contamination. 

Carbon Sequestration Council Comments 

As stated in the Council's December 23, we support the use of this approach and 

these criteria to the extent necessary to protect USDWs. We see, however, no 

411
particular reason why these criteria could not be specified and considered as 

part of the regular permit application process when injection is proposed for a 

saline injection zone that is overlying a USDW. 

Individual Response: As described above, EPA agrees that it is appropriate to consider and evaluate 

the waiver application in concert with the UIC permit application, and not under a separate process. 

For this reason, the final requirements at §146.95 create an application and review process for GS 

injection depth waivers that is integrated with the UIC permit application process while ensuring that 

the proposed project is considered in the context of the presence of USDWs above and below the 

injection zone and potential impacts on water systems. 

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. If the permitting authority receives comments on the injection depth waiver during the 

public comment period for both the waiver and the permit application, the Director in consultation with 

the Regional Administrator, must evaluate comments prior to providing a recommendation to the 

Regional Administrator regarding a waiver and issuing the Class VI permit. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28147 

Comment: In the event that the Director is not given discretion to make such 

determinations, Spectra supports the concept of a waiver process to allow 

injection above the lowermost USDW; however, we recommend a simple process 

improvement. As proposed in the NODA, the supporting data required for the 

waiver application is virtually the same extensive information required for the 

full GS operation application; this creates an onerous process for both the 

regulatory agencies and the applicant. Therefore to prevent the proliferation of 

redundant material and hearings, yet still ensure the regulatory agency has 

412
adequate data on the proposal, we recommend the waiver be an additional form 

filed along with the initial GS application and not a separate application 

process. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit. The Agency believes that this report and requirements at §146.95 are 

complementary and not redundant of the Class VI permit application requirements. Furthermore, to 

eliminate concerns about duplication or redundancy, the requirements at §146.82(d) clarify that the 

supplemental report is not part of the permit application.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

413
Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28573 

Comment: principle but needs revisions. First, the waiver application should be submitted 

as an additional form with the initial GS scheme application and should not 

require a separate application process with redundant data submittal. Second, 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver 

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit. The Agency believes that this report and requirements at §146.95 are 

complementary and not redundant of the Class VI permit application requirements. Furthermore, to 

eliminate concerns about duplication or redundancy, the requirements at §146.82(d) clarify that the 

supplemental report is not part of the permit application.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

414
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28324 

Comment: Class VI UIC Program. EPA should integrate the waiver process into the normal 

permit approval process as much as possible. For example, combining the public 

hearing for the waiver along with the public hearing for the permit, if one is 

held. 

Individual Response: EPA agrees that it is appropriate to consider and evaluate the waiver

application in concert with the UIC permit application, and not under a separate process. For this 

reason, the final requirements at §146.95 create an application and review process for GS injection 

depth waivers that is integrated with the UIC permit application process while ensuring that the 

proposed project is considered in the context of the presence of USDWs above and below the injection 

zone and potential impacts on water systems.

For example, rather than submit a separate waiver application, owners or operators seeking waivers 

must provide a supplemental report (the GS Class VI injection depth waiver application report) 

referenced at §146.82(d) and outlined at §146.95(a) with additional, site-specific information relevant 

to operation under an injection depth waiver. This report, suggested by commenters, is designed to 

ensure that all waiver information is discrete (from the permit application) and can be made available 

to the Director, PWSS Directors, and the public when the waiver is publicly noticed. The UIC permit 

application and waiver application would be reviewed together. If the permitting authority receives 

comments on the injection depth waiver during the public comment period for both the waiver and the 

permit application, the Director in consultation with the Regional Administrator, must evaluate 

comments prior to providing a recommendation to the Regional Administrator regarding a waiver and 

issuing the Class VI permit. The Agency believes that this report and requirements at §146.95 are 

complementary and not redundant of the Class VI permit application requirements. Furthermore, to 

eliminate concerns about duplication or redundancy, the requirements at §146.82(d) clarify that the 

supplemental report is not part of the permit application.

In addition, the public notification process for the waiver must occur concurrently with the UIC permit 

notification to ensure that all necessary information is disclosed to the public for notice and comment 

and that the public understands that the site, if permitted, would be operating under a waiver from 

the injection depth requirements as specified in §146.95(c). EPA believes these requirements balance 

USDW protection and disclosure of PWSS information with the GS permit application process 

requirements. 

415
EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3370 3.3.7. Notice and Hearing 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27996 

Other EPA Comment Codes and Descriptions: 3350 3.3.5. Requirement to Submit Waiver 

Application to UIC and PWSS Program Directors 

Comment: Comment No. 54 

Page 44811 

Issue Topic from EPA's NODA 

The waiver may also be subject to local notice and public hearing. Following a 

public hearing and waiver approval by both Program Directors, the owner/operator 

may complete and submit the Class VI permit application. 

Carbon Sequestration Council Comments 

The authority for granting a waiver should rest solely with the state UIC 

primacy agency. It would, however, seem appropriate to provide a special 

notification to the PWSS Director with opportunity to comment. 

416
Individual Response: EPA believes that informing and consulting with the PWSS Directors of all 

states, Territories, and Tribes having jurisdiction within the AoR of a well for which a waiver is sought 

as specified in §146.95(b)(2) is necessary and appropriate to ensure that water system concerns are 

considered when evaluating a waiver application. EPA requires that this consultation be documented to 

ensure transparent public disclosure of all information evaluated by the Directors and their respective 

recommendations. 

EPA clarifies that the final determination regarding waiver issuance will be made by the Director, 

following evaluation of all site-specific information, public notice, and receipt of written concurrence or 

non-concurrence from the Regional Administrator. EPA believes Agency input is necessary in making 

injection depth waiver decisions and agrees with commenters who expressed interest in ensuring that 

multi-state boundary and water resource issues are addressed. The Agency also believes that Agency 

involvement in the waiver decision process will contribute to national consistency in waiver issuance. 

EPA Team Member:

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28107 

Comment: As with AMWA’s comments on EPA’s original proposal for any GS project that could 

affect current or future water supplies, a public process and opportunity for 

public comment must be a prerequisite for a waiver application. As recommended 

in our December 2008 comments, AMWA also believes that local drinking water 

utilities should be notified directly and invited to participate in the public 

proceedings. Protection of water supplies should be given the highest priority; 

transparency of the waiver process, including public disclosure of modeling and 

monitoring results, are essential elements in preserving the public trust. 

Individual Response: EPA agrees that local drinking water entities should be consulted and provided 

an opportunity to inform in the waiver application evaluation process. In addition to the requirement 

for consultation with the PWSS Directors of all States, Territories, and Tribes having jurisdiction within 

the AoR of a well for which a waiver is sought as specified in §146.95(b)(2), the public notification 

process for the waiver must occur concurrently with the UIC permit notification as specified in 

§146.95(c). EPA believes this requirement is necessary to ensure that appropriate information is 

417
disclosed to the public for notice and comment and that the public understands that the site, if 

permitted, would be operating under a waiver. EPA believes these requirements balance USDW 

protection and disclosure of PWSS information with the GS permit application process requirements. 

EPA has also added a requirement at §124.10(c)(1)(xi) that state and local oil and gas regulatory 

agencies and state agencies regulating mineral exploration and recovery, the PWSS program director, 

and all agencies that oversee injection wells in the state must be notified as part of the public notice 

process for all Class VI permits. For additional information on the requirements for public notification 

associated with GS permitting, see the preamble to the final rule and the responses to comments on 

the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John V. Corra 

Commenter Organization: Wyoming Department of Environmental Quality (WDEQ) 

EPA Letter ID: 0386 

EPA Comment ID: 28158 

Comment: Comment: Requirement that the waiver may be subject to local notice and public 

hearing 

While we recognize and appreciate the need for the public to be informed when a 

GS project has applied for a waiver, we believe that the requirement for a 

public hearing may be unnecessary in many cases, especially where the project 

will have little, if any, effect upon the local populace, as may be the case in 

sparsely populated western states. We would prefer that the option for a public 

hearing remain at the discretion of the Director, and avoid the requirement for 

public hearing when there may be little, if any public interest. Upon public 

notice, interested citizens should have the opportunity to request a public 

hearing, and it is reasonable to expect that many Directors would voluntarily 

schedule public hearings for GS projects that involve potentially controversial 

waivers. We would remind US EPA that, under its proposed GS regulation, public 

notice is required and the public has an opportunity to request a public hearing 

once the draft permit is noticed. 

Recommendation: We recommend that there be no requirement for public hearing on 

GS waiver applications, but that the Director be provided discretion to hold 

418
public hearings as he/she deems necessary. 

Individual Response: EPA disagrees that public hearings should be optional. The Agency believes 

that public participation is an important part of the UIC permitting process and wants to ensure wide 

access to decision-making processes and information on projects that may affect the public, 

particularly where waivers are under consideration. 

The final GS rule requires that the public notification process for a waiver of injection depth 

requirements for a Class VI well occur concurrently with permit notification in order to ensure that all 

necessary information is disclosed to the public for notice and comment and that the public 

understands that the site, if permitted, would be operating under a waiver. The rule at §146.95(c) 

requires the Director to provide the public with appropriate, site-specific, and waiver-specific 

information to inform public comment. These requirements balance USDW protection and disclosure of 

PWSS information with the GS permit application process requirements. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28303 

Comment: Second, if the EPA allows for a waiver process, the EPA should ensure that 

waiver decisions are subject to public notice and comment. EPA should ensure 

that the final rule includes ample public involvement at the earliest possible 

stage of a waiver decision to gain public trust and acceptance of its decisions. 

This gives the community time to process the complicated and voluminous 

information involved in a siting and waiver decision. It also will mitigate some 

controversial issues and potentially avoid litigation and other delays. 

As Sierra Club noted in its December comments, public acceptance of CCS is a 

major issue. Innumerable reports and recommendations from the federal government 

and top scientists, institutions and workgroups stress that the success of a CCS 

program will depend heavily on public acceptance. The National Academy of 

Sciences cautioned "the storage program cannot be successful if a significant 

fraction of the public views it as dangerous or unacceptable. Thus, CCS 

419
technologies must not only be safe and effective, it must be explainable to the 

public in such as way as to instill confidence that they are in fact safe and 

effective."[FOOTNOTE 5] The International Risk Governance Council recommends 

that regulatory frameworks must include "effective risk communication to engage 

and educate the public, involve all stakeholders in risk-related decisions, and 

build confidence in the institutions governing CCS." [FOOTNOTE 6] The Clean Air 

Act Advisory Committee’s Advanced Coal Technology Work Group’s January 2008 

report similarly highlighted the need for public outreach.[FOOTNOTE 7] The need to gain 

public acceptance will be especially crucial with early projects. Since 

injection above USDWs are likely to be more controversial, EPA should mitigate 

anticipated controversy by requiring that draft waiver decisions are subject to 

public notice and comment. 

[FOOTNOTE 5]: U.S. GAO Report. CLIMATE CHANGE: Federal Actions will Greatly 

Affect the Viability of Carbon Capture and Storage As a Key Mitigation Option, 

GAO-08-1080, September 2008 (quoting National Academy of Sciences, Prospective 

Evaluation). 

[FOOTNOTE 6]: IRGC, Regulation of Carbon Capture and Storage, p. 24, available 

at http://www.irgc.org/IMG/pdf/Policy_Brief_CCS.pdf (last visited December 17, 

2008). 

[FOOTNOTE 7]: January 29, 2008 Final Report, available at 

http://www.epa.gov/air/caaac/coaltech/2008_01_final_report.pdf (last visited 

December 17, 2008). 

Individual Response: EPA agrees that local drinking water entities should be consulted and provided 

an opportunity to inform in the waiver application evaluation process. In addition to the requirement 

for consultation with the PWSS Directors of all States, Territories, and Tribes having jurisdiction within 

the AoR of a well for which a waiver is sought as specified in §146.95(b)(2), the public notification 

process for the waiver must occur concurrently with the UIC permit notification as specified in 

§146.95(c). EPA believes this requirement is necessary to ensure that appropriate information is 

disclosed to the public for notice and comment and that the public understands that the site, if 

permitted, would be operating under a waiver. EPA believes these requirements balance USDW 

protection and disclosure of PWSS information with the GS permit application process requirements. 

EPA has also added a requirement at §124.10(c)(1)(xi) that state and local oil and gas regulatory 

agencies and state agencies regulating mineral exploration and recovery, the PWSS program director, 

and all agencies that oversee injection wells in the state must be notified as part of the public notice 

process for all Class VI permits. For additional information on requirements for public notification 

420
associated with GS permitting, see the preamble to the final rule and the responses to comments on 

the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3380 3.3.8. Additional Requirements Established by the UIC Director 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael J. Miller 

Commenter Organization: Electric Power Research Institute (EPRI) 

EPA Letter ID: 0355 

EPA Comment ID: 28085 

Comment: EPRI’s next comment is based on (a) the following EPA assumption: "The basis of 

these requirements is the principle that placing distance between the injection 

formation and USDWs decreases risks to USDWs" (Page 44809), and (b) the 

statement that "The owner/operator may be required to comply with additional 

requirements that apply as a result of receipt of the waiver, designed to ensure 

the protection of USDWs both above and below the injection zone." (Page 44811). 

EPRI COMMENT#8: EPA’s technical rationale for wanting to include additional 

requirements in the permit waiver beyond those already required for an injection 

into a zone located below the lowermost USDW is unclear. EPA’s justification 

appears to be based on vertical position of the injection zone relative to the 

adjacent USDWs and intervening distance between the two. Injection below the 

lowermost USDW appears to be viewed by EPA as being less risky than injection 

above the lowermost USDW, even though the upper boundary condition could be 

identical in both cases. For example, one could propose a GS project with 

421
injection immediately below the lowermost USDW with only one intervening 

confining unit of given thickness (i.e., distance) between it and the lowermost 

USDW above to prevent CO2 migration. Likewise, one could propose a GS project 

above the lowermost USDW with the same identical upper boundary condition (i.e. 

one intervening confining unit with same thickness) relative to the next USDW 

above. The risk of impact from CO2 migration into the overlying USDW is 

identical. See figure below for illustration of this concept. 

This figure illustrates that injection of CO2 into the center zone below identical 

confining units having identical properties (including thickness) will result in identical risks to the 

overlying USDW regardless whether injection is occurring above or below the lowermost USDW. [SEE 

P. 6 of EPA-HQ-OW-2008-0390-0355.PDF FOR FIGURE.] 

The EPA draft standard published in July 2008 for injection below the lowermost 

USDW appears to be deemed adequately protective of USDWs above by EPA. EPRI 

sees no physical reason why the same standards would not be equally protective 

of USDWs if injection occurs into a zone above the lowermost USDW, when the 

boundary conditions and risks are essentially identical. Therefore, EPRI 

questions the need for additional well construction, operational or monitoring, 

as required by the proposed waiver process, regardless of vertical position; it 

appears that the Agency has already taken this scenario into account in the July 

2008 draft rule. 

One could argue that the lower boundary doubles the risk for a GS project 

injecting above the lowermost USDW increases the risk of a project because 

contamination of this lower USDW could occur from above (refer to figure). 

However, it is the transmissivity and lateral continuity of the upper and lower 

seals that control CO2 migration across the boundary that defines the risk, not 

the number of boundaries. (i.e., one or two) across which CO2 could migrate to 

adjacent USDWs. In addition, it is far less likely that free CO2 will migrate 

across the lower boundary because CO2 is buoyant. Saline groundwater (and CO2 

dissolved in the same) could potentially be displaced below the lower seal, but 

the requirements in the draft standards published by EPA in July 2008 already 

affords adequate USDW protection against these mechanisms - i.e., EPA’s current 

draft rule already accounts for the worst case scenario (displaced water 

containing dissolved CO2 and free CO2). 

Individual Response: EPA believes that that injection for the purpose of GS into non-USDW 

formations above the lowermost USDW warrants tailored requirements to address the unique 

challenges and risks relative to injection below the lowermost USDW. For example, there is a risk of 

422
downward migration of fluids if there is no lower confining layer or inadequate confinement. In 

addition, there is potential that wells will be drilled through the injection zone in the future to reach 

USDWs. EPA believes that the additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements at §146.95 will provide additional 

considerations for the owner or operator and Director when permitting such wells to ensure protection 

of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27997 

Comment: Comment No. 55 

Page 44811 

Issue Topic from EPA's NODA 

The owner/operator may be required to comply with additional requirements that 

apply as a result of receipt of the waiver, designed to ensure the protection of 

USDWs both above and below the injection zone. 

Carbon Sequestration Council Comments 

Appropriate permit conditions may be included as necessary to ensure the 

protection of USDWs both above and below the injection zone. As with other 

requirements of the proposed rule, additional requirements under the proposed 

waiver should be appropriate and site specific. For example, seismic plume 

tracking may not be possible in some instances but other monitoring methods may 

provide sufficient protection of USDWs. 

Individual Response: EPA agrees that all requirements for GS projects, including those operating 

under injection depth waivers, must be based on site-specific conditions. The requirements at §146.95 

that allow owners or operators to seek a waiver from the injection depth requirements for GS wells are 

423
designed to ensure that the owner or operator submit and the Director consider, on a site-specific 

basis, the implications, benefits, and challenges associated with GS and ensuring water availability 

and USDW protection. EPA believes that the additional requirements that apply to owners or operators 

of Class VI wells granted a waiver of the injection depth requirements at §146.95 will provide 

additional considerations for the owner or operator and Director when permitting such wells to ensure 

protection of all USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3390 3.3.9. Comments Regarding State Discretion to Adopt the Waiver 

Approach 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28199 

Comment: 16. For pragmatic reasons, with respect to deployment of GS at least, State 

Discretion and Delegation should be maximized; as well as the cooperative 

relationships with external expertise, whether State or not, that USEPA has 

already established. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

424
asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their

State, Territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Nightingale 

Commenter Organization: Illinois Environmental Protection Agency (IEPA) 

EPA Letter ID: 0333 

EPA Comment ID: 28201 

Other EPA Comment Codes and Descriptions: 3360 3.3.6. Requirement to Apply for Waiver 

Separately from UIC Permit Application (seeking comment) 

Comment: III. Consideration of New Approach (pg 44810- 44812) 

Beginning on p. 44810, under the heading "Consideration of New Approach," and 

through p. 44812, the Illinois EPA would like to comment on the proposed waiver 

approach. If a facility wanted to inject above or between USDWs, the proposed 

waiver approach would unduly burden the State UIC program by requiring the 

states to determine site suitability and appropriate injection depth. The State 

of Illinois is in a financial situation in which we have very limited resources 

for the evaluations required under the proposed waiver process. The Illinois EPA 

anticipates that within the next year we will lose more resources due to 

financial restraints. Additionally, there has been no guidance provided as to 

how to accurately evaluate these sites to make a determination on injection 

depths. Therefore, we recommend that U.S. EPA Region V evaluate all the waivers 

that may be requested under these proposed Class VI rules. The U.S. EPA would 

need to provide more funding to the State programs if the waiver approach is 

approved and the additional burden placed on the State regulators. The U.S. EPA 

does not provide enough funding to the State programs to even support the 

425
current UIC programs. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. 

EPA is developing a series of guidance documents to support Class VI owners and operators and 

Directors including guidance on the injection depth waiver process. The guidance describes the 

recommended approach an owner or operator may follow when submitting a waiver application, 

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations 

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s 

website at http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Olon Plunk 

Commenter Organization: Xcel Energy, Inc. 

EPA Letter ID: 0344 

EPA Comment ID: 27876 

Comment: Xcel Energy supports EPA's continued collaborative effort with states in the 

development of the Class VI application and approval process. Permitting 

decisions are best made at the state level where there is knowledge of local 

geologic conditions and awareness of public concerns. Xcel Energy supports the 

concept that states should have the ability to obtain only Class VI delegation 

authority. 

426
Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27881 

Comment: While AEP supports the flexible injection depth waiver proposal described above, 

AEP urges EPA to consider requiring the inclusion of such a waiver provision, 

rather than leaving the adoption of an injection depth waiver process to the 

discretion of the individual VIC Program Directors. Id. at 44811. While it is 

true that deep USDWs do not exist in every state and that states without USDWs 

may choose not to grant waivers, inclusion of a waiver provision would still leave UIC Program 

Directors free to decline to grant any waivers 

where not necessary or appropriate. See id. CO2 GS technology is rapidly 

developing; because this experience with and information regarding this 

technology is growing rapidly, it is prudent to structure a regulatory framework 

that is flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

427
make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara A. Walz 

Commenter Organization: Tri-State Generation and Transmission Association, Inc. (Tri-State) 

EPA Letter ID: 0346 

EPA Comment ID: 27890 

Comment: Tri-State urges EPA to consider requiring the inclusion of such a waiver 

provision, rather than leaving the adoption of an injection depth waiver process 

to the discretion of the individual UIC Program Directors [Id. at 44811]. 

Inclusion of a waiver provision would retain for UIC Program Directors 

prerogative to decline to grant any waivers where not necessary or appropriate. 

See id. Since CO2 GS technology is rapidly developing, it is prudent to 

structure a regulatory framework that is flexible enough to respond to 

developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

428
are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James F. Stine 

Commenter Organization: National Rural Electric Cooperative Association 

EPA Letter ID: 0348 

EPA Comment ID: 27906 

Comment: While NRECA supports the flexible injection depth waiver proposal described 

above, NRECA urges EPA to consider requiring the inclusion of such a waiver 

provision, rather than leaving the adoption of an injection depth waiver process 

to the discretion of the individual UIC Program Directors. Id. at 44811. While 

it is true that deep USDWs do not exist in every state and that states without 

USDWs may choose not to grant waivers, inclusion of a waiver provision would 

still leave UIC Program Directors free to decline to grant any waivers where not 

necessary or appropriate. See id. CO2 GS technology is rapidly developing; 

because this experience with and information regarding this technology is 

growing rapidly, it is prudent to structure a regulatory framework that is 

429
flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James R. Roewer 

Commenter Organization: Utility Solid Waste Activities Group (USWAG) 

EPA Letter ID: 0349 

EPA Comment ID: 28035 

Comment: While USWAG supports the flexible injection depth waiver proposal described 

above, USWAG urges EPA to consider requiring the inclusion of such a waiver 

provision, rather than leaving the adoption of an injection depth waiver process 

to the discretion of the individual UIC Program Directors. Id. at 44811. While 

it is true that deep USDWs do not exist in every state and that states without 

USDWs may choose not to grant waivers, inclusion of a waiver provision would 

430
still leave UIC Program Directors free to decline to grant any waivers where not 

necessary or appropriate. See id. As USWAG noted in our original comments in 

response to the proposed rule, CO2 GS technology remains in the nascent stage; 

because this experience with and information regarding this technology is 

growing rapidly, it is prudent to structure a regulatory framework that is 

flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Claire M. Olson 

Commenter Organization: Basin Electric Power Cooperative (Basin Electric) 

EPA Letter ID: 0351 

EPA Comment ID: 28056 

431
Comment: While Basin Electric supports the flexible injection depth waiver proposal 

described above, we urge EPA to consider requiring the inclusion of such a 

waiver provision, rather than leaving the adoption of an injection depth waiver 

process to the discretion of the individual UIC Program Directors. Id. at 44811. 

While it is true that deep USDWs do not exist in every state and that states 

without USDWs may choose not to grant waivers, inclusion of a waiver provision 

would still leave UIC Program Directors free to decline to grant any waivers 

where not necessary or appropriate. See id. CO2 GS technology is rapidly 

developing; because this experience with and information regarding this 

technology is growing rapidly, it is prudent to structure a regulatory framework 

that is flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Paul R. Pike 

432
Commenter Organization: Ameren Corporation 

EPA Letter ID: 0354 

EPA Comment ID: 28073 

Comment: While Ameren supports the flexible injection depth waiver proposal described 

above, we urge EPA to consider requiring the inclusion of such a waiver 

provision, rather than leaving the adoption of an injection depth waiver process 

to the discretion of the individual UIC Program Directors. Id. at 44811. While 

it is true that deep USDWs do not exist in every state and that states without 

USDWs may choose not to grant waivers, inclusion of a waiver provision would 

still leave UIC Program Directors free to decline to grant any waivers where not 

necessary or appropriate. See id. CO2 GS technology is rapidly developing; 

because this experience with and information regarding this technology is 

growing rapidly, it is prudent to structure a regulatory framework that is 

flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

433
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John A. Gulvas 

Commenter Organization: Consumers Energy (CE) 

EPA Letter ID: 0356 

EPA Comment ID: 28089 

Comment: While CE supports the flexible injection depth waiver proposal described above, 

we urge EPA to consider requiring the inclusion of such a waiver provision, 

rather than leaving the adoption of an injection depth waiver process to the 

discretion of the individual UIC Program Directors. Id. at 44811. While it is 

true that deep USDWs do no exist in every state and that states without USDWs 

may choose not to grant waivers, inclusion of a waiver provision would still 

leave UIC Program Directors free to decline to grant any waivers where not 

necessary or appropriate. See id. CO2 GS technology is rapidly developing; 

because this experience with and information regarding this technology is 

growing rapidly, it is prudent to structure a regulatory framework that is 

flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

434
Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28225 

Comment: -Making Clear States’ Role in Site Determinations/Technical Assessments: We 

appreciate EPA’s explicit nod to states’ expertise in grappling with the many 

and varied issues that will arise in the context of CO2 sequestration. We agree 

states should play the key role in assessing and making determinations on key 

technical issues such as appropriate injection depths of a given CO2 CCS 

project. We believe more needs to be done in this area (See our comments 

below.) 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. 

EPA clarifies that adoption of the waiver process remains at the discretion of individual UIC programs. 

Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are not required to 

provide for injection depth waivers in their UIC regulations and may choose not to make this process 

available to Class VI wells under their jurisdiction. Although some commenters asked EPA to require 

that waivers be applied nationally, the Agency believes that the decision about whether a waiver 

program is appropriate in a specific State, Tribe, or Territory should be made by each program. This 

approach allows flexibility for individual program Directors to determine the appropriateness of 

allowing for waivers based on regional or state-specific conditions, such as the predominant geologic 

settings anticipated to be used for GS or other land uses in the state while ensuring maximum 

protection of USDWs. The final approach for injection depth waivers represents minimum Federal 

requirements. UIC program Directors may adopt GS requirements that do not allow injection above or 

between USDWs if they determine this to be appropriate (for conditions in their State, territory, Tribe, 

or Region) and protective.

435
Regarding decisions on granting of injection depth waivers, EPA clarifies that, pursuant to §146.95(d), 

the Regional Administrator will make the final determination whether to issue an injection depth 

waiver. However, prior to a final decision, the Director must provide the Regional Administrator with 

the information collected during the waiver application and the public notice processes. Based on this 

information and pursuant to requirements at §146.95(d), the Regional Administrator will provide 

written concurrence or non-concurrence regarding waiver issuance. The Agency clarifies that these 

requirements are within the authority of the Safe Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

EPA Letter ID: 0360 

EPA Comment ID: 28242 

Comment: While NRG supports the flexible injection depth waiver proposal described above, 

NRG urges EPA to consider requiring the inclusion of such a waiver provision, 

rather than leaving the adoption of an injection depth waiver process to the 

discretion of the individual UIC Program Directors. Id. at 44811. While it is 

true that deep USDWs do not exist in every state and that states without USDWs 

may choose not to grant waivers, inclusion of a waiver provision would still 

leave UIC Program Directors free to decline to grant any waivers where not 

necessary or appropriate. See id. CO2 GS technology is rapidly developing; 

because this experience with and information regarding this technology is 

growing rapidly, it is prudent to structure a regulatory framework that is 

flexible enough to respond to developments in the field. 

Individual Response: EPA clarifies that adoption of the injection waiver process will remain at the 

discretion of individual UIC programs. States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations. Although some 

commenters asked EPA to require that waivers be applied nationally, the Agency believes that the 

decision about whether a waiver program is appropriate should be made by each program. This 

approach allows flexibility for individual program Directors to determine the appropriateness of

allowing for waivers based on regional or state-specific conditions, such as the predominant geologic 

settings anticipated to be used for GS or other land uses in the state while ensuring maximum 

protection of USDWs. The final approach for injection depth waivers represents minimum Federal 

436
requirements. UIC program Directors may adopt GS requirements that do not allow injection above or 

between USDWs if they determine this to be appropriate (for conditions in their State, territory, Tribe, 

or Region) and protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an 

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects, 

including information on any Class VI wells granted a waiver of the injection depth requirements, to 

determine whether the appropriate amount and types of information and appropriate documentation 

are being collected, and to determine if modifications to the requirements are appropriate or 

necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28244 

Comment: State discretion with respect to adoption of an injection depth waiver process 

In the august 31,2009 notice of data availability and request for comment 

(noda), the epa requested comment on a proposed waiver process that would allow 

as injection above and between underground sources of drinking water (usdws) 

under specific conditions in lieu of a blanket prohibition on injection above 

and between usdws. 

We support the EPA 's approach in this NODA that adoption of any such injection 

depth waiver process should be at the discretion of the UIC Program Director, 

and that UIC Programs in States may instead adopt and enforce the proposed 

requirements that injection for as be below the lowermost USDW. 

Further, we appreciate that EP A reiterates in the NODA that States and UIC 

Directors have discretion to be more stringent in writing regulations for as 

and/or adopting Federal UIC requirements. As such, States have discretion to 

include a minimum injection depth requirement in their regulations; or, as an 

alternate approach, Directors may impose such requirements on a site specific 

437
basis. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28276 

Comment: Because of the importance of the waiver proposal APS asks that EPA consider 

requiring the inclusion of this waiver provision, rather than leaving the 

adoption of an injection depth waiver process to the discretion of the 

individual UIC Program Directors. 74 Fed. Reg. 44811. Inclusion of a waiver 

provision would still leave UIC Program Directors free to decline to grant any 

waivers where not necessary or appropriate. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

438
whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Stroben 

Commenter Organization: Duke Energy Corporation 

EPA Letter ID: 0368 

EPA Comment ID: 27929 

Comment: As EPA works to complete the subject rulemaking, Duke Energy urges the Agency to 

incorporate an appropriately designed injection depth waiver process in its 

final rule, rather than leaving the adoption of an injection depth waiver 

process to the discretion of the individual UIC Program Directors. Inclusion of 

a waiver provision would still leave UIC Program Directors free to decline to 

grant any waivers where they were not necessary or appropriate. Duke Energy 

further encourages EPA to consider and incorporate additional flexibility 

measures that will enhance the workability of the program while ensuring that 

potentially undesirable impacts to UDWS are avoided. Having a workable 

regulatory program in place for the GS of CO2 is absolutely essential to this 

country's ability to make significant reductions in greenhouse gas emissions at 

a reasonable cost and without eliminating coal as a viable energy resource. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

439
appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Stan Belieu 

Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC) 

EPA Letter ID: 0378 

EPA Comment ID: 28570 

Comment: To address Nebraska’s lack of non-USDWs we applaud EPAs proposal of a waiver 

system. However, for the waiver system to work effectively, the final decision 

making authority for a waiver should be with the agency holding primacy for the 

proposed Class VI UIC program. In Nebraska, UIC primacy lays with NDEQ and 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA clarifies that, under the injection depth waiver approach, owners or operators may only inject into 

non-USDWs. 

440
Regarding decisions on granting of injection depth waivers, EPA clarifies that, pursuant to §146.95(d), 

the Regional Administrator will make the final determination whether to issue an injection depth 

waiver. However, prior to a final decision, the Director must provide the Regional Administrator with 

the information collected during the waiver application and the public notice processes. Based on this 

information and pursuant to requirements at §146.95(d), the Regional Administrator will provide 

written concurrence or non-concurrence regarding waiver issuance. The Agency clarifies that these 

requirements are within the authority of the Safe Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27978 

Comment: Comment No. 35 

Page 44810 

Issue Topic from EPA's NODA 

EPA believes this approach may additionally accommodate requests for geographic 

flexibility while placing such determinations at the State or Regional level. 

Carbon Sequestration Council Comments 

These determinations should be at the state or regional level, although EPA 

Regions often will not be in a position to make these determinations as 

effectively as a state agency because the EPA regional offices typically have 

limited involvement in the related areas of program oversight. Where EPA 

regional offices are making permitting decisions for Class VI wells, they should 

coordinate with the relevant state agencies. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

441
make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, Territory, Tribe, or Region) and protective.

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27998 

Comment: Comment No. 56 

Page 44811 

Issue Topic from EPA's NODA 

Due to the range of concerns and comments related to the injection depth 

requirements and the nature of the suggested waiver approval procedure, EPA 

believes that adoption of any such injection depth waiver process, as previously 

described, should be at the discretion of the UIC Program Director. 

442
Carbon Sequestration Council Comments 

There should not be a requirement for states to make special application to 

conduct a waiver program; the use of formations above the lowermost USDW should 

be available where permit requirements can be met. States already have the 

ability to impose more stringent requirements if they choose to do that. 

Individual Response: As described above, adoption of the waiver process will remain at the 

discretion of individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for 

Class VI wells are not required to provide for injection depth waivers in their UIC regulations and may 

choose not to make this process available to Class VI wells under their jurisdiction. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28149 

Comment: F. States should be required to accept the waiver process unless they have 

primacy over the entire UIC Rule 

Allowing states to opt out of the waiver process creates additional regulatory 

uncertainty, which will further slow the process of making CCS commercially 

viable. By requiring States to accept the waiver process, EPA is not authorizing 

injection above the lowermost USDW in all situations; even if a State accepts 

the waiver process, the responsible agencies still have the authority to decline 

a waiver request. 

Additionally, EPA should be thorough in reviewing State capabilities prior to 

granting States primacy over the Class VI well program because of the unique 

technical issues associated with GS. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

443
are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective. EPA also clarifies that states choosing to adopt the 

waiver would include this as part of their Class VI primacy application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28575 

Comment: operations such as gas storage, production and geologic sequestration. Third, 

States should not be able to opt out of the waiver process unless they have 

primacy for entire UIC program. 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

444
State, territory, Tribe, or Region) and protective. EPA also clarifies that states choosing to adopt the 

waiver would include this as part of their Class VI primacy application. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28302 

Comment: B. If the EPA Allows Injection Above the Lowermost USDW, then EPA Should Not 

Provide States Waiver Discretion and Should Require Public Participation. 

In the NODA, EPA states that it may be appropriate to create a waiver process 

that would allow injection above the lowermost USDW. 74 Fed. Reg. at 44,810. At 

this time, Sierra Club takes no position regarding whether it is appropriate to 

allow injection above USDWs. However, Sierra Club notes two problems with the 

proposed inclusion of the waiver. 

First, if the EPA decides to allow for a waiver process, it should not allow 

states the discretion to issue a waiver. Instead, the EPA itself should 

administer any waiver program with the assistance of a CCS technical advisory 

committee, a proposal the Sierra Club discussed in depth in our December 

comments. 

In the NODA, EPA states that the "owner or operator would be required to 

demonstrate to regulatory authorities that such injection can be undertaken and 

completed in a manner that prevents fluid movement into overlying (and 

underlying) USDWs." 74 Fed. Reg. at 44,810. State regulatory authorities are not 

properly equipped to demonstrate that injection will not lead to fluid movement 

into USDWs. Permit decisions require evaluation of many complicated technical 

issues that demand a high level of expertise and there are scores of 

uncertainties at this early stage of CCS development. There is also cause for 

concern over the capacity and competency of some state regulatory agencies to 

properly regulate a CCS program. State permitting decisions can contradict 

science and logic and produce dangerous results for local health and welfare. 

For instance, the Florida Department of Environmental Protection approved the 

445
construction and operation of a facility designed to inject more than 112 

million gallons of treated sewage a day, erroneously believing that the 

subsurface geology would prevent the injected sewage from migrating into the 

overlying Floridan Aquifer. Most experts agreed that the injection program 

should not have been permitted, and eventually the injected sewage migrated 

upward into the Floridan Aquifer. Even after evidence of contamination was wellestablished, Florida continued to expand its injection program. The Florida 

program was supposed to prevent the migration of sewage into overlying USDWs. 

Given such track records, states should not have the discretion to issue waivers 

for injection above the lowermost USDWs. 

Individual Response: As described above, EPA believes that there are some situations where 

injection into non-USDW formations above the lowermost USDW can be performed in a manner that 

protects USDWs.

EPA clarifies that adoption of the waiver process remains at the discretion of individual UIC programs. 

Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are not required to 

provide for injection depth waivers in their UIC regulations and may choose not to make this process 

available to Class VI wells under their jurisdiction. Although some commenters asked EPA to require 

that waivers be applied nationally, the Agency believes that the decision about whether a waiver 

program is appropriate in a specific State, Tribe, or Territory should be made by each program. This 

approach allows flexibility for individual program Directors to determine the appropriateness of 

allowing for waivers based on regional or state-specific conditions, such as the predominant geologic 

settings anticipated to be used for GS or other land uses in the state while ensuring maximum 

protection of USDWs. The final approach for injection depth waivers represents minimum Federal 

requirements. UIC program Directors may adopt GS requirements that do not allow injection above or 

between USDWs if they determine this to be appropriate (for conditions in their State, territory, Tribe, 

or Region) and protective.

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

446
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28323 

Comment: Second, for the waiver system to work effectively, the final decision-making 

authority for waiver should be with the agency holding primacy for the proposed 

Class VI UIC Program. EPA should integrate the waiver process into the normal 

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of 

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells 

are not required to provide for injection depth waivers in their UIC regulations and may choose not to 

make this process available to Class VI wells under their jurisdiction. Although some commenters 

asked EPA to require that waivers be applied nationally, the Agency believes that the decision about 

whether a waiver program is appropriate in a specific State, Tribe, or Territory should be made by 

each program. This approach allows flexibility for individual program Directors to determine the 

appropriateness of allowing for waivers based on regional or state-specific conditions, such as the 

predominant geologic settings anticipated to be used for GS or other land uses in the state while 

ensuring maximum protection of USDWs. The final approach for injection depth waivers represents 

minimum Federal requirements. UIC program Directors may adopt GS requirements that do not allow 

injection above or between USDWs if they determine this to be appropriate (for conditions in their 

State, territory, Tribe, or Region) and protective.

EPA clarifies that, pursuant to §146.95(d), the Regional Administrator will make the final 

determination whether to issue an injection depth waiver. However, prior to a final decision, the 

Director must provide the Regional Administrator with the information collected during the waiver 

application and the public notice processes. Based on this information and pursuant to requirements at 

§146.95(d), the Regional Administrator will provide written concurrence or non-concurrence regarding 

waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe 

Drinking Water Act. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3400 3.4 Additional Information Regarding the Waiver Approach 

447
EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Paque 

Commenter Organization: Ground Water Protection Council (GWPC) 

EPA Letter ID: 0373 

EPA Comment ID: 28021 

Comment: 3. There is some question as to how wells converted to Class VI from Class II 

would be handled under the waiver process. Would a waiver be required for such 

wells and under what circumstances? 

Individual Response: If an owner or operator is transitioning a well from Class II to Class VI that 

injects above the lowermost USDW, they must apply for a waiver from the injection depth 

requirements pursuant to §146.95. EPA clarifies that the final GS rule contains risk-based criteria at 

§144.19 to inform a Director’s determination to apply Class VI requirements to wells transitioning 

from an ER project to a project for which the primary purpose is long-term storage of CO2. For 

additional information on transitioning of Class II wells for GS, see the preamble to the final rule and 

the responses to comments on the proposed GS rule.

EPA is developing guidance on transitioning from Class II to Class VI. The guidance will assist 

Directors and owner or operators in evaluating where a project may fit within a Class II to Class VI 

transition. The guidance describes the methods available for the Director to determine the risk posed 

to USDWs from a GS/ER project, and how the Director may determine if a project should be regulated 

within the Class II or Class VI UIC program. This guidance will be available on EPA’s website at 

water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-SEP-10 

Notes: 

448
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27986 

Comment: Comment No. 43 

Page 44810 

Issue Topic from EPA's NODA 

This process would be separate from aquifer exemptions and has no effect on 40 

CFR Parts 144.7 and 146.4. 

Carbon Sequestration Council Comments 

In many cases, waivers are likely to require an aquifer exemption for the 

injection zone itself. Consequently, it is unclear as to how a waiver process 

would be beneficial to either state agencies or applicants. If states still 

need to obtain an aquifer exemption; which must be approved by EPA, we believe 

this would negate the benefit of a waiver process that does not require EPA 

approval. Further, 40 CFR Part 146.4 does not currently have a criterion for 

aquifer exemption on the basis of "use as a storage zone for CO2 

geosequestration". Since no changes to the aquifer exemption criteria have been 

proposed, it appears that obtaining an exemption for USDWs above the lowermost 

USDW for the purpose of geosequestration would be very difficult. In effect, 

this would create a requirement for injection below the lowermost USDW 

regardless of whether or not a waiver process exists. 

Individual Response: EPA acknowledges that there are limited circumstances where aquifer 

exemptions for GS may be warranted or needed. The final rule allows for the expansion of the areal 

extent of existing aquifer exemptions for Class II EOR/EGR wells transitioning to Class VI injection for 

GS pursuant to requirements at §§146.4 and 144.7(d). Class VI owners or operators granted 

expansions of existing Class II EOR/EGR aquifer exemptions for GS projects must meet all of the 

tailored requirements for GS wells in the final GS rule. However, the final rule precludes the issuance 

of new aquifer exemptions for Class VI GS wells; that is, aquifer exemptions will only be granted for 

projects that are transitioning from Class II EOR/EGR wells to Class VI. 

449
The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances.

EPA clarifies that all decisions regarding whether expansion of existing aquifer exemptions will be at 

the Director's discretion and based on site-specific information. If an owner or operator applies for a 

Class VI permit to inject CO2 into a previously exempted aquifer (non-USDW) that is located above 

and/or between USDWs, the permit applicant must also apply for a waiver of the injection depth 

requirements pursuant to §146.95 to ensure that if a waiver is granted, USDWs above and below the 

injection zone are protected from endangerment. The Agency clarifies that it is anticipated that both of 

these tools will be used in limited circumstances. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28134 

Comment: The Agency proposes that applicants for a waiver be required to consider several 

issues related to water supply, including "regional water resource issues" and 

"alternative water supplies or water treatment options to address unanticipated 

movement of the injectate or formation fluids." Further, the NODA may be read 

to suggest that injection depth limitations are desirable to protect for 

underground waters not meeting the Agency’s current definition of USDW (i.e., 

10,000 ppm total dissolved solids (TDS)) and that any waiver decisions also may 

take into consideration the protection of such underground waters. EEI does not 

dispute the benefits of requiring waiver applicants to consider potential issues 

related to water supply or water treatment, or the need to consider potential 

technological advancements in terms of underground water access and treatment. 

However, USDWs, the subject of the UIC program’s protection, are defined only to 

include those below 10,000 ppm TDS. Absent a proposal to change the definition 

of USDW, the Agency must work within the current definition and craft any 

450
injection depth limitations with it in mind. 

Individual Response: The requirements to consider water issues related to water supply, including 

regional water resource issues and alternative water supplies or water treatment options to address 

unanticipated movement of the injectate or formation fluids at §146.95 are to ensure consideration of 

water system and water resource issues where injection into non-USDW formations above the 

lowermost USDW is being considered. 

EPA is not changing the definition a USDW; changing the definition of a USDW is outside the scope of 

the GS rulemaking. The GS rule focuses on ensuring protection of USDWs, as required under the 

SDWA, by establishing regulations to ensure the safe injection of CO2 for long-term storage. For 

additional information on EPA's approached to USDW protection, see the preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3410 3.4.1. Applicability of Waiver Process to Deep Saline and Other Types of 

Formations (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28045 

Comment: API, while supportive of the concept of a waiver process, has concerns with how 

the proposed waiver process would function. First, the scope and applicability 

of the proposed waiver process appears very limited. EPA's apparent intent is 

451
to issue waivers for situations where the injection zone is 1) a saline 

formation overlying a USDW or 2) a depleted oil or gas reservoir overlying a 

USDW. With respect to the former situation, these conditions are relatively 

uncommon and would not address the problem faced in large portions of the 

western US where USDWs may extend from the surface to very great depths. 

Applicability would also be limited in the latter situation because frequently 

the water legs of oil and gas reservoirs meet the definition of a USDW. In 

effect then, a waiver may not be sufficient to inject into such a depleted oil 

and gas reservoir without also obtaining an aquifer exemption. 

Individual Response: EPA clarifies that injection depth waivers are required in all situations where 

CO2 injection for GS would be above the lowermost USDW. EPA believes the requirements at §146.95 

are necessary to ensure USDW protection above and below the injection zone and offer additional 

flexibility and capacity beyond what was contained in the proposed GS rule. EPA recognizes that there 

may still be regions where GS would be prohibited but clarifies that USDW protection is the primary 

purpose of the GS rule.

EPA acknowledges that there are limited circumstances where aquifer exemptions for GS may be 

warranted. The final rule allows for the expansion of the areal extent of existing aquifer exemptions 

for Class II EOR/EGR wells transitioning to Class VI injection for GS pursuant to requirements at 

§§146.4 and 144.7(d). Class VI owners or operators granted expansions of existing Class II EOR/EGR 

aquifer exemptions for GS projects must meet all of the tailored requirements for GS wells in the final 

GS rule. However, the final rule precludes the issuance of new aquifer exemptions for Class VI GS 

wells; that is, aquifer exemptions will only be granted for projects that are transitioning from Class II 

EOR/EGR wells to Class VI. 

The Agency clarifies that the aquifer exemption requirements and the injection depth waiver 

requirements serve different purposes. Class VI owners or operators granted expansions of existing 

Class II EOR/EGR aquifer exemptions for GS projects must meet all of the tailored requirements for 

GS wells in the final GS rule, including the site criteria at §146.83. EPA believes that, in most cases, 

the injection depth waiver is a more appropriate option than aquifer exemptions for Class VI injection, 

and believes that aquifer exemption expansions for GS should be granted in limited circumstances. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

452
Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28223 

Comment: We also support the Agency’s decision to remove explicit prohibitions against 

injection into specific formation types like basalts and/or coal seams. We 

agree with the Agency that all formations should be afforded equal treatment 

under the regulations. 

We appreciate EPA’s further refinement of this crucial issue. By allowing more 

areas to be considered for geologic sequestration, EPA is removing a very 

significant hurdle to the advancement of a viable commercial CO2 CCS program. 

It will begin to address some of the concerns we expressed in our original 

comments regarding the need for regulatory flexibility and the importance of 

site-specific assessments. 

Individual Response: EPA agrees that the GS rule should not categorically preclude or prohibit 

injection into any type of formation. EPA believes that the requirements that allow owners or 

operators to seek waivers from the injection depth requirements at §146.95, along with proper siting, 

well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure that USDWs are protected from endangerment.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

a manner that protects USDWs, as required in the GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28260 

453
Comment: III. Specific Comments 

a. Project Siting 

The proposed regulations as originally issued would not permit project operators 

to inject and store CO2 above the lowermost formation containing a USDW. As 

explained in its prior comments, NACCSA believes that a categorical elimination 

of receiving formations is unnecessary and undesirable. Rather, the 

appropriateness of any given receiving formation - as with the bulk of issues 

related to the siting of projects - should be considered on a case-by-case basis 

in light of the geologic characteristics of a given project and based on the 

application of clear and appropriate parameters set forth in the rules. 

Categorically eliminating a set of potential receiving formations is simply 

unnecessary in light of the overall function of the UIC rules. As a general 

proposition, permit applicants must demonstrate that projects will not endanger 

USDW; permit applicants for CO2 injection and storage projects would be held to 

the same standard. The proposed rules would require permit applicants to 

demonstrate that the project will be sited in areas with a "suitable geologic 

system," consisting of an injection zone of sufficient areal extent, thickness, 

porosity, and permeability to receive the total anticipated volume of injectate, 

as well as a confining zone free of transmissive faults or fractures and 

sufficient to contain the injected stream and any displaced fluids, considering 

the proposed maximum pressures and volumes of injection, without fracturing. It 

is NACCSA's view that if the "suitable geologic system" contains confining zones 

above and below the injection formation that will not allow the endangerment of 

USDW, injection above a USDW should be allowed because the system will still 

meet the groundwater protection requirements of the UIC program. The fact that 

permit applications would be considered based on site specific information would 

mean that the regulator could evaluate whether individual projects would be 

protective of groundwater regardless of their depth with respect to USDW. 

Individual Response: EPA agrees and clarifies that the GS rule does not categorically preclude or 

prohibit injection into any type of formation. EPA believes that the requirements that allow owners or 

operators to seek waivers from the injection depth requirements at §146.95, along with proper siting, 

well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure USDW protection.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

454
a manner that protects USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28166 

Comment: B. Definitions in the NODA 

1. Definition of Class VI well as proposed does not "preclude" or prohibit 

injection into basalts, coal seams, salt caverns and shales, and GS in such 

formations should be excluded from Class VI at this time 

EPA mistakenly asserts that the definition of a Class VI well }[a]s proposed, 

... would ... preclude the injection of CO2 into shallow formations such as coal 

seams and basalts." [FOOTNOTE 3] In fact, the definition of a Class VI well as 

proposed only states that a Class VI well is one “used for geologic 

sequestration of carbon dioxide beneath the lowermost formation containing an 

underground source of drinking water (USDW). [FOOTNOTE 4] As basalts and coal 

seams can be found in areas beneath the lowermost USDW, or in areas where there 

is no USDW, this definition actually does not preclude or prohibit injection 

into basalts or coal seams, shallow or otherwise. 

FOOTNOTE 3- 74 Fed. Reg. 44808. 

FOOTNOTE 4- 73 Fed. Reg. at 43535. 

Individual Response: EPA agrees and clarifies that the rule does not preclude injection into coal 

seams or basalts. EPA believes that the requirements that allow owners or operators to seek waivers 

from the injection depth requirements at §146.95, along with proper siting, well construction, 

operation, monitoring, and post-injection site care pursuant to the GS rule requirements will ensure 

USDW protection. 

EPA Team Member: 

Draft Status: 

455
Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28167 

Comment: A more important point, however, and one raised in both our earlier comments and 

today’s comments, is that an affirmative prohibition on the inclusion of 

basalts, coal seams, salt caverns and shales in Class VI is warranted based on 

the state of the science at present. EPA should adopt regulatory language 

containing such a prohibition. [FOOTNOTE 5] Such language need not be added to the 

definition of a Class VI well, but it is not sufficient simply to assert in a 

preamble that the current language preclude such injection. Experimentation 

with GS in basalts, coal seams, salt caverns and shales should continue under 

Class V for the foreseeable future. 

FOOTNOTE 5 - Also refer to Multi-Stakeholder Group letter of May 14. 2009, which 

supported the exclusion of GS in basalts, coal seams, salt caverns, and shales 

from Class VI. 

Individual Response: EPA disagrees that categorically precluding or prohibiting injection into any 

type of formation is appropriate. Instead, construction and operation of a Class VI well for injection 

into shallower formations can be permitted if an owner or operator can demonstrate, pursuant to the 

requirements at §146.95, that injection can be performed in a manner that protects USDWs and if the 

owner or operator meets the other protective requirements at §146.82 through §146.94. EPA believes 

that the injection depth waiver requirements at §146.95, along with proper siting, well construction, 

operation, monitoring, and post-injection site care pursuant to the GS rule requirements will ensure 

USDW protection.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

a manner that protects USDWs. 

EPA recognizes that it may be appropriate to conduct injection into certain formation types (e.g., in 

456
basalts, coal seams, salt caverns, and shales) on a small scale as experimental projects; such wells 

could be permitted as Class V experimental technology wells. To facilitate experimental injection for 

GS and to increase global understanding of injection into these formation types, the Agency is 

preparing an addendum to the Class V experimental technology guidance on wells that meet the 

criteria. The decision about whether a well should be permitted as a Class V experimental technology 

well or a Class VI well will be site-specific and depend on the nature of the project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28173 

Comment: D. CO2 Injection Above the Lowermost Formation Containing a USDW and Other Issues 

1. Injection into coal seams and basalts 

As noted above, the currently proposed definition of a Class VI well confines GS 

to geologic formations located below the lowermost USDW. [FOOTNOTE 12] While 

EPA asserts that "as proposed, the definition would also preclude injection of 

CO2 into shallow formations such as coal seams and basalts," in fact that is 

not the case. First, USDWs do not exist everywhere, and there may be shallow 

coal seams and basalts in areas where there is not USDW. Second, shallow basalts 

and coal seams may be located below the lowermost USDW. We continue to assert 

that the Agency should prohibit Class VI wells in basalts, coal seams, salt 

caverns and shales regardless of injection depth. 

FOOTNOTE 12 - See proposed 40 C.F.R. §§ 144.6(f), 144.80(f) 146.5(f). at 73 Fed. 

Reg. 43534-43535. 

As we noted in our December comments: [FOOTNOTE 13] there is no significant 

prior experience or consensus on how to assess and manage risks, what data is 

needed to characterize sites, how to select sites, how to conduct and manage 

injection operations, how to model the behavior of CO2, and how to monitor 

project performance of CO2 sequestration in basalts, coal seams, salt caverns 

and shales. The trapping mechanisms of CO2 and/or the operational engineering 

457
involved in such operations is significantly different from those in deep saline 

formations and hydrocarbon reservoirs. We simply do not know at this time 

whether sequestration (or even injection in some cases) can even be done at 

scale in such formations. 

FOOTNOTE 13 - Joint Environmental Group Comments at 11 (Dec. 24, 2008). 

Due to this fundamentally different nature of GS in these formations, if EPA 

decides not to explicitly prohibit Class VI wells in such formations, it must 

provide substantial evidence of the scientific basis on which it bases its 

belief that the physical processes, operational engineering, and risks involved 

are similar to and/or equally mature as those in saline formations or oil/gas 

reservoirs. We believe that such a demonstration is important both as a policy 

matter and a legal matter. 

We reassert that until there is better understanding of whether and how 

sequestration can be safely accomplished in basalts, coal seams, salt caverns 

and shales, wells in these formations should be treated as experimental and 

regulated under UIC Class V. 

Individual Response: As described above, EPA disagrees that categorically prohibiting injection into 

any type of formation is appropriate. EPA recognizes that injection into basalts, coal seams, salt 

caverns, and shales have been the subject of limited experimental projects in the past. However, EPA 

believes that the GS rule provides safeguards to allow, on a site-specific basis, GS in other formation 

types, provided the owner or operator demonstrates to the Director's satisfaction that the formations 

are suitable for receiving and confining injected CO2 as specified at §146.83. The siting, well 

construction, operational, and other requirements in the GS rule are designed to ensure that injected 

CO2 remains within the target formation. 

As described above, small-scale, experimental injection into shallow basalts, coal seams, salt caverns 

and shales; such wells would be permitted as Class V experimental technology wells. See the 

preamble to the final rule and the responses to comments on the proposed GS rule for additional 

information on EPA's approach to injection into various formation types. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

458
Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27974 

Comment: Comment No. 31 

Page 44809 

Issue Topic from EPA's NODA 

Furthermore, some specific research on CO2 injection for GS into various 

formations including shallow, volcanic rocks such as flood basalts (McGrail, et 

al., 2006) and coal seam injection (Dooley, et al., 2006; IPCC, 2005; MIT 2007; 

White et al., 2005) illustrates the potential for GS in these formations, but 

only if there is depth requirement flexibility. 

Carbon Sequestration Council Comments 

The Council agrees that broad categories of formations should not be arbitrarily 

excluded from use solely on the grounds of underlying USDWs. Site selection 

should be able to consider all locations and receiving injection zones that can 

meet the siting requirements by providing sufficient containment of CO2streams. 

The proposed exclusion of formations is thus inconsistent with EPA's basic 

adaptability approach in disallowing for the advancements that may result from 

research and development projects that identify additional suitable types of 

formations for GS. 

The Council has joined with other MSD participants to recommend that[w]ells in 

basalts, coal seams, salt caverns and shale formations should be treated as 

experimental wells under Class V, recognizing that completing the process of 

research, development and demonstration likely will require initial full scale 

experimental projects in addition to pilot projects. 

"Keeping these wells under Class V would allow EPA and the states to gain enough 

experience to develop suitable permitting requirements for such wells and to 

tailor those requirements at both the pilot and commercial scales until the 

agencies are ready to regulate such wells under an appropriate class." MSD 

Recommendation Letter, May 14, 2009, Item 1. 

459
Individual Response: EPA agrees and clarifies that the GS rule does not categorically preclude or 

prohibit injection into any type of formation. EPA believes that the requirements that allow owners or 

operators to seek waivers from the injection depth requirements at §146.95, along with proper siting, 

well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure USDW protection.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

a manner that protects USDWs. 

EPA adds that wells used to inject into these formations types or other formation types (e.g., salt 

domes and shales) for experimental purposes would be permitted as Class V experimental technology 

wells. To facilitate experimental injection for GS and to increase global understanding of injection into 

basalts, shales, and other formation types, the Agency is preparing an addendum to the Class V 

experimental technology guidance on wells that meet the criteria. The decision about whether a well 

should be permitted as a Class V experimental technology well or a Class VI well will be site-specific 

and depend on the nature of the project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 20-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27980 

Comment: Comment No. 37 

Page 44810 

Issue Topic from EPA's NODA 

Second, the alternative under consideration does not prohibit injection into any 

specific formation types (e.g., basalts and/or coal seams). It affords all 

formations equal treatment and allows specific regions of the country the 

regulatory flexibility to determine if any injection at a particular site and 

460
depth is the appropriate approach. It will also help to manage injection in 

areas where there may be multiple, stratified formations with significant 

assessed cumulative capacity. 

Carbon Sequestration Council Comments 

We are supportive of EPA's effort to introduce flexibility on the depth of 

injection relative to the location of USDWs by proposing a waiver process. As 

stated in our December 24, 2008 Comments, we agree that CO2 can be injected 

above a USDW while protecting the USDW and maintaining access to the USDW for 

future use. As noted in our Comments, the Salt Creek EOR project in Wyoming, 

which has a USDW below the injection zone, is an excellent example of how 

industry can operate CO2 injection wells in an EOR context without endangering 

or limiting access to USDWs that are located below the injection zone. 

Accessing USDWs below a CCS site, while not trivial, does not present 

significant technological hurdles. Industry has the technology to drill through 

over-pressured gas reservoirs which are analogous to CCS sites. There are some 

excellent examples of off-shore technologies for drilling through salt 

formations and shallow gas pockets that involve the same type of pressure issues 

that would be encountered in drilling through a CCS site. 

Individual Response: EPA agrees that the GS rule should be flexible and not categorically preclude 

or prohibit injection into any type of formation. EPA believes that the requirements that allow owners 

or operators to seek waivers from the injection depth requirements at §146.95, along with proper 

siting, well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure USDW protection.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

a manner that protects USDWs. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text that is later repeated in lines 945 to 957. Part of this comment 

appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

461
Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27999 

Comment: Comment No. 57 

Page 44811 

Issue Topic from EPA's NODA 

Some stakeholders are concerned about the risks associated with the use of 

formations other than deep saline and depleted reservoirs (e.g., coal seams, 

basalts, etc.). EPA is seeking comment on whether the waiver process should 

apply to formations other than these. 

Carbon Sequestration Council Comments 

The Council has joined with other MSD participants to make specific 

recommendations regarding these types of formations: 

"We agree that EPA has ample basis for adopting rules to regulate GS in 

hydrocarbon reservoirs and in deep saline formations under the SDWA. For these 

types of geologic formations, there is a widespread technical consensus on how 

to assess and manage risks, what data is needed to characterize sites, how to 

select sites, how to conduct injection operations, how to model the behavior of 

CO2 in the reservoir, and how to monitor project performance. 

"There is less technical support on the ability to conduct GS in basalts, coal 

seams, salt caverns, and shales. As compared with deep saline formations and 

hydrocarbon reservoirs, the trapping/containment mechanisms of CO2 and/or 

operational engineering involved in basalts, coal seams, salt caverns and shales 

may be significantly different and using identical regulatory language might not 

be appropriate. In fact, it is not known at this time whether GS (or even 

injection in some cases) can be done at commercial scale in each of these types 

of formations - GS efforts in these formations are still in the experimental 

stage. Wells in basalts, coal seams, salt caverns and shale formations should be 

treated as experimental wells under Class V, recognizing that completing the 

process of research, development and demonstration likely will require initial 

full scale experimental projects in addition to pilot projects. 

462
"Keeping these wells under Class V would allow EPA and the states to gain enough 

experience to develop suitable permitting requirements for such wells and to 

tailor those requirements at both the pilot and commercial scales until the 

agencies are ready to regulate such wells under an appropriate class. 

"To implement this approach, sections 144.6(f), 144.80(f), 146.5(f) and the 

definition of sequestration in 146.81 should be revised. The proposed 144.15 

provision that the construction, operation or maintenance of any nonexperimental Class V GS well is prohibited should be retained, but only with the 

understanding that this prohibition is not intended to limit the size or scale 

of any experimental GS operation." MSD Recommendation Letter May 14, 2009, Item 

1. 

Individual Response: EPA agrees that it may be appropriate to conduct injection into certain 

formation types (e.g., in basalts and coal seams) on a small scale as experimental projects; such wells 

would be permitted as Class V experimental technology wells. To facilitate experimental injection for 

GS and to increase global understanding of injection into these formation types, the Agency is 

preparing an addendum to the Class V experimental technology guidance on wells that meet the 

criteria. The decision about whether a well should be permitted as a Class V experimental technology 

well or a Class VI well will be site-specific and depend on the nature of the project. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28400 

Comment: As discussed in our original comment submittal, Spectra recommends that EPA not 

arbitrarily preclude injection above the lowermost Underground Source of 

Drinking Water (USDW); the decision should be based on the geology of the area. 

Spectra believes that it is premature for the Agency to preclude the injection 

of CO2 into formations such as unmineable coal seams, depleted oil and gas 

reservoirs, zones in between or above USDWs, or other formations. As EPA points 

out, imposing such a limit may preclude the application of GS in areas such as 

the Williston and Powder River Basins in Wyoming and the Dakotas, where the 

463
lowermost USDW is located thousands of feet below the surface. In these cases, 

we agree with EPA that GS may still be appropriate and, therefore, the Director 

should have the discretion to make such determinations. Such determination must 

ultimately be made based on the protection of USDWs. 

Individual Response: EPA agrees and clarifies that the GS rule does not categorically preclude or 

prohibit injection into any type of formation. EPA believes that the requirements that allow owners or 

operators to seek waivers from the injection depth requirements at §146.95, along with proper siting, 

well construction, operation, monitoring, and post-injection site care pursuant to the GS rule 

requirements will ensure USDW protection.

EPA recognizes that some types of formations, such as coal seams and basalts, are typically shallow 

and above the lowermost USDW. The Agency expects that injection for GS into these shallow 

formations can be issued waivers and permitted as Class VI wells, provided their owners or operators 

can meet all of the requirements at §146.95 and demonstrate that such injection can be performed in 

a manner that protects USDWs. 

EPA adds that wells used to inject into these formations types or other formation types (e.g., salt 

domes and shales) for experimental purposes would be permitted as Class V experimental technology 

wells. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28296 

Comment: I. Class VI Wells Should Be Permitted Only in Oil and Gas Reservoirs and Deep 

Saline Formations. 

EPA has not proposed changes, in the NODA, to any of the regulatory language 

included in the Notice of Proposed Rulemaking. Therefore, Sierra Club assumes 

that the "definitions" included in the NODA are meant for clarity only, and do 

not indicate any intention by the Agency to change those definitions. 

464
The proposed regulations allow for injection into unmineable coal seams, 

basalts, salt caverns, and shales. The proposed regulations define Class VI as 

one "used for geologic sequestration of carbon dioxide beneath the lowermost 

formation containing an underground source of drinking water (USDW)." 73 Fed. 

Reg. 43,492, 43,535 (July 25, 2008). As basalts and coal seams are found in 

areas beneath the lowermost USDW, or in areas where there is no USDW, this 

definition allows injection into basalts or coal seams, shallow or otherwise. 

In the NODA, EPA erroneously claims that the definition of a Class VI well "[a]s 

proposed, ... would ... preclude the injection of CO2 into shallow formations 

such as coal seams and basalts." 74 Fed. Reg. 44,802, 44,808 (Aug. 31, 2009). As 

we noted in our December comments: EPA should revise this definition section to 

prohibit injection into unmineable coal seams, basalts, salt caverns, and shales 

until further studies are completed and CCS potential in these formations is 

better understood. EPA lacks an adequate scientific basis to develop regulations 

for commercial-scale sequestration projects in these formations because "the 

process of CO2 adsorption to coal has not been proven and the chemical reactions 

of supercritical CO2 within coal formations are not well understood." 73 Fed. 

Reg. 43,492, 43,503. Sequestration in coal seams is "an emerging technology that 

is in the demonstration phase." Id. As far as basalts, shales and salt caverns, 

EPA has noted that their "technical or economic viability as GS sites have not 

been demonstrated." Id. 

The IPCC CCS report supports EPA’s conclusions and goes a step further, 

concluding that "basalts appear unlikely to be suitable for CO2 storage." 

[FOOTNOTE 3] The IPCC agrees that coalbed storage technology "is not well 

developed and a better understanding of injection and storage processes in coals 

is needed." [FOOTNOTE 4] 

[FOOTNOTE 3]: IPCC CCS § 5.3.5.1. 

[FOOTNOTE 4]: IPCC CCS Chapt. 5 Exec. Summary; see also § 5.3.4. 

Precautionary principles demand that the first Class VI permits are issued for 

injection into geological formations with the greatest degree of scientific 

certainty, where any damages would be minimal - namely, depleted oil and gas 

reservoirs and deep saline formations. Accordingly, initial Class VI wells 

should not include coal seams, basalts, shales, and salt caverns regardless of 

whether they are above or below the deepest USDW. Continued research is 

appropriate for geological sequestration projects in these formations. 

465
Finally, due to this fundamentally different nature of geological sequestration 

in these formations, if EPA decides not to explicitly prohibit Class VI wells in 

such formations, it must provide substantial evidence of the scientific basis on 

which it bases its belief that the physical processes, operational engineering, 

and risks involved are similar to and/or equally mature as those in saline 

formations or oil/gas reservoirs. Sierra Club believes that such a demonstration 

is important both as a policy matter and a legal matter. 

Individual Response: EPA disagrees that categorically precluding or prohibiting injection into any 

type of formation is appropriate. Instead, construction and operation of a Class VI well for injection 

into shallower formations can be permitted if an owner or operator can demonstrate, pursuant to the 

requirements at §146.95, that injection can be performed in a manner that protects USDWs and if the 

owner or operator meets the other protective requirements at §146.82 through §146.94. EPA believes 

that the injection depth waiver requirements at §146.95, along with proper siting, well construction, 

operation, monitoring, and post-injection site care pursuant to the GS rule requirements will ensure 

USDW protection.

EPA recognizes that injection into basalts, coal seams, salt caverns, and shales have been the subject 

of limited experimental projects in the past. However, EPA believes that the GS rule provides 

safeguards to allow, on a site-specific basis, GS in other formation types, provided the owner or 

operator demonstrates to the Director's satisfaction that the formations are suitable for receiving and 

confining injected CO2 as specified in §146.83. The siting, well construction, operational, and other 

requirements in the GS rule are designed to ensure that injected CO2 remains within the target 

formation. 

EPA adds that it has revised the definition of a Class VI well to read as follows: “Wells that are not 

experimental in nature that are used for geologic sequestration of carbon dioxide beneath the 

lowermost formation containing a USDW; or, wells used for geologic sequestration of carbon dioxide 

that have been granted a waiver of the injection depth requirements pursuant to requirements at 

§146.95 of this chapter; or, wells used for geologic sequestration of carbon dioxide that have received 

an expansion to the areal extent of an existing Class II enhanced oil recovery or enhanced gas 

recovery aquifer exemption pursuant to §§146.4 of this chapter and 144.7(d).” 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

466
Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28300 

Comment: A. Injection into coal seams and basalts 

In the original proposed rule, EPA required that injection of CO2 must occur 

beneath the lowermost formation containing a USDW. In the NODA, EPA proposes 

possibly creating a waiver process so that injection could occur above or 

between USDWs. 74 Fed. Reg. at 44,810. One of the reasons provided by the EPA 

regarding why this waiver process is appropriate is because "as proposed, the 

definition would also preclude injection of CO2 into shallow formations such as 

coal seams and basalts." 74 Fed. Reg, at 44,808. 

First, as noted above, the EPA’s statement that the current regulations prohibit 

injection into coal seams and basalts is wrong because the currently proposed 

definition of a Class VI wells allows injection unmineable coal seams, basalts, 

salt caverns, and shales. See proposed 40 C.F.R. §§ 144.6(f), 144.80(f) 146.5(f) 

at 73 Fed. Reg. 43,534-43,535. 

Second, the EPA should not create a waiver process that allows injection above 

or between USDWs to promote injection into coal seams and basalts as these 

formations are not appropriate injection formations. As discussed above and in 

our previous comments there is no significant prior experience or consensus on 

how to assess and manage risks, what data is needed to characterize sites, how 

to select sites, how to conduct and manage injection operations, how to model 

the behavior of CO2, and how to monitor project performance of CO2 sequestration 

in basalts, coal seams, salt caverns and shales. The trapping mechanisms of CO2 

and/or the operational engineering involved in such operations is significantly 

different from those in deep saline formations and hydrocarbon reservoirs. We 

simply do not know at this time whether sequestration (or even injection in some 

cases) can even be done at scale in such formations. Therefore, the EPA should 

not change the prohibition on injections above USDWs to promote use of these 

sites. 

Individual Response: As described above, the GS rule does not categorically preclude or prohibit 

injection into any type of formation. Instead, construction and operation of a Class VI well for injection 

into shallower formations can be permitted if an owner or operator can demonstrate, pursuant to the 

requirements at §146.95, that injection can be performed in a manner that protects USDWs and if the 

owner or operator meets the other protective requirements at §146.82 through §146.94. 

467
EPA believes it may be appropriate to conduct small-scale, experimental injection into shallow basalts, 

coal seams, salt caverns and shales; such wells would be permitted as Class V experimental 

technology wells. To facilitate experimental injection for GS and to increase global understanding of 

injection into these formation types, the Agency is preparing an addendum to the Class V 

experimental technology guidance on wells that meet the criteria. For additional information on EPA's 

approach to injection into various formation types, see the preamble to the final rule and the 

responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3420 3.4.2. Request for Information on Areas Where Injection Depth and 

USDWs Are a Concern (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28210 

Other EPA Comment Codes and Descriptions: 3430 3.4.3. Request for Information on 

Constructing Wells Through Existing CO2 Plumes (seeking comment) 

Comment: On the Appropriateness of Allowing CO2 Storage above a USDW and the related 

issue of who will regulate production wells that could intersect stored CO2? The 

overriding principle should be does the proposed Class VI rule help protect the 

wellbeing of humans and the health of the environment. Framing the issue in this 

way makes it clear that there is an explicit tradeoff being made about the use 

of USDWs for CO2 storage or the use of water bearing bodies that have more than 

468
10,000 TDS but are shallower than another formation which has waters with less 

than 10,000 TDS. This calls for a flexible and site- or region-specific approach 

that still includes mandatory criteria such as the presence of adequate caprocks 

above and below the proposed storage formation to ensure the protection of both 

shallower and deeper USDWs. 

Individual Response: EPA clarifies that the GS rule sets requirements for siting of GS projects, 

including the presence of adequate confining zones above (and where waivers are issued, below) the 

injection zone for the purpose of protecting USDWs from endangerment. EPA adds that the GS rule 

does not promote the use of any formations for GS over other uses. 

Finally, EPA clarifies that regulating production wells is outside the UIC program’s authority, but adds 

that the presence of production wells in the AoR of a Class VI well must be considered in the AoR and 

corrective action plan. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mark Bohrer 

Commenter Organization: North Dakota Industrial Commission (NDIC) 

EPA Letter ID: 0343 

EPA Comment ID: 28566 

Comment: Accessing USDWs below a GS site is not technically challenging. Industry has 

developed the ability to safely drill through over-pressured reservoirs which 

may be analogous to GS sites. There are several formations in North Dakota 

which are over- pressured and the industry routinely can safely drill through 

these by taking the appropriate precautions. 

Individual Response: EPA acknowledges that technologies and past experience exist to inject 

through over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry 

experience in drilling through shallow pockets of gas or other zones that have higher pressures). EPA 

has reviewed information on these types of projects and has determined that, if properly constructed, 

wells can be drilled through pressurized zones without causing fluid movement. However, to provide 

additional USDW protection and ensure that any planned drilling is conducted appropriately, the final 

GS rule requires the Director to consider planned or permitted water, hydrocarbon, or mineral 

469
resource exploitation potential of the proposed injection formation and other formations both above 

and below the injection zone to determine if there are any plans to drill through the formation to 

access resources in or beneath the proposed injection zone/formation as specified in 

§146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from lines 50 to 54, which is an excerpt from the previous section, 

lines 38 to 54. This comment appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28567 

Comment: USDWs that are located below the injection zone. Accessing USDWs below a 

storage site, while not trivial, does not present significant technological 

hurdles. Industry has the technology and experience needed to drill through 

over-pressured gas reservoirs which are analogous to GS sites. There are some 

excellent examples of off-shore technologies for drilling through salt 

formations and shallow gas pockets that involve the same type of pressure issues 

that would be encountered in drilling through a GS site. 

Individual Response: EPA acknowledges that technologies and past experience exist to inject 

through over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry 

experience in drilling through shallow pockets of gas or other zones that have higher pressures). EPA 

has reviewed information on these types of projects and has determined that, if properly constructed, 

wells can be drilled through pressurized zones without causing fluid movement. However, to provide 

additional USDW protection and ensure that any planned drilling is conducted appropriately, the final 

GS rule requires the Director to consider planned or permitted water, hydrocarbon, or mineral 

resource exploitation potential of the proposed injection formation and other formations both above 

and below the injection zone to determine if there are any plans to drill through the formation to 

access resources in or beneath the proposed injection zone/formation as specified in 

§146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 290 to 296, which is an excerpt from the previous 

470
section, lines 283 to 296. This comment appears twice in this report, once for each set of line 

numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Stan Belieu 

Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC) 

EPA Letter ID: 0378 

EPA Comment ID: 28568 

Comment: Accessing USDWs below a GS site is not technically challenging. Industry has 

developed the ability to safely drill through over-pressured reservoirs which 

may be analogous to GS sites. 

Individual Response: EPA acknowledges that technologies and past experience exist to inject 

through over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry 

experience in drilling through shallow pockets of gas or other zones that have higher pressures). EPA 

has reviewed information on these types of projects and has determined that, if properly constructed, 

wells can be drilled through pressurized zones without causing fluid movement. However, to provide 

additional USDW protection and ensure that any planned drilling is conducted appropriately, the final 

GS rule requires the Director to consider planned or permitted water, hydrocarbon, or mineral 

resource exploitation potential of the proposed injection formation and other formations both above 

and below the injection zone to determine if there are any plans to drill through the formation to 

access resources in or beneath the proposed injection zone/formation as specified in 

§146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from lines 56 to 58, which is an excerpt from the previous section, 

lines 32 to 58. This comment appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Rebecca Thingelstad 

Commenter Organization: Anadarko Petroleum Corporation (APC) 

EPA Letter ID: 0380 

EPA Comment ID: 28091 

Other EPA Comment Codes and Descriptions: 3210 3.2.1. Comments Generally in Support of the 

Approach 

471
Comment: Injection Depth for GS Projects 

APC is supportive of EPA’s effort to introduce flexibility on the depth of 

injection relative to the location of USDWs. APC holds that CO2 can be injected 

above a USDW while protecting the USDW and maintaining access to the USDW for 

future use. Anadarko’s Salt Creek EOR project in Wyoming, which has a USDW below 

the injection zone, is an excellent example of how industry can operate CO2 

injection wells in an EOR context without endangering or limiting access to 

USDWs that are located below the injection zone. Accessing USDWs below a CCS 

site does not present significant technological hurdles. Industry has the 

technology to drill through over-pressured gas reservoirs which are analogous to 

CCS sites. There are some excellent examples of off-shore technologies for 

drilling through salt formations and shallow gas pockets that involve the same 

type of pressure issues that would be encountered in drilling through a CCS 

site. 

Individual Response: EPA acknowledges the commenter's support of the waiver approach and sitespecific flexibility in regulatory development and permitting as described in the NODA and Request for 

Comment. The Agency acknowledges that there are some situations where injection into non-USDW 

formations above the lowermost USDW can be performed in a manner that protects USDWs. The final 

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the 

Class VI injection depth requirements. The Agency believes the waiver approach: 1) responds to 

concerns about local and regional geologic storage capacity limitations imposed by the proposed 

injection depth requirements; 2) allows for a more site-specific assessment of injection depth for GS 

projects; 3) accommodates injection into different formation types; 4) allows for injection of CO2 for 

GS into non-USDWs above and/or between USDWs when appropriate and where it can be 

demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aquifer 

exemptions for GS. Finally, EPA's approach to addressing injection depth variability through a waiver 

process responds to concerns about future drinking water resource availability and the need to ensure 

that high quality water remains available in sufficient quantities to supply drinking water needs.

EPA acknowledges that technologies and past experience exist to inject through over-pressured 

formations while maintaining zonal isolation (e.g., oil and gas industry experience in drilling through 

shallow pockets of gas or other zones that have higher pressures). EPA has reviewed information on 

these types of projects and has determined that, if properly constructed, wells can be drilled through 

pressurized zones without causing fluid movement. However, to provide additional USDW protection 

and ensure that any planned drilling is conducted appropriately, the final GS rule requires the Director 

to consider planned or permitted water, hydrocarbon, or mineral resource exploitation potential of the 

proposed injection formation and other formations both above and below the injection zone to 

determine if there are any plans to drill through the formation to access resources in or beneath the 

472
proposed injection zone/formation as specified in §146.95(b)(1)(vii). EPA believes that these 

additional considerations are necessary when permitting such wells to ensure protection of all USDWs 

and that the additional requirements that apply to owners or operators of Class VI wells granted a 

waiver of the injection depth requirements at §146.95 will provide this protection. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 28000 

Comment: Comment No. 58 

Page 44811-44812 

Issue Topic from EPA's NODA 

Additionally, the Agency is interested in: 1) Information on specific areas of 

the United States where injection depth and USDW depth are of concern (including 

formation depth, location, and assessed capacity; demonstrated confinement and 

GS suitability; and, formation salinity/TDS) as determined by well-log analyses, 

cross sections, and formation fluid analyses; 2) Data, information, and evidence 

from owners and operators constructing and operating injection wells through 

existing CO2 plumes to access resources (e.g., water, hydrocarbon, etc.) below 

the injection zone and whether or not such operations are safe and do not 

endanger USDWs; and, 3) Strategies that States, Tribes, and regions are 

considering to manage competing GS and resource issues. 

Carbon Sequestration Council Comments 

As noted in our Comments, the Salt Creek EOR project in Wyoming, which has a 

USDW below the injection zone, is an excellent example of how industry can 

operate CO2 injection wells in an EOR context without endangering or limiting 

access to USDWs that are located below the injection zone. Accessing USDWs 

below a CCS site, while not trivial, does not present significant technological 

hurdles. Industry has the technology to drill through over-pressured gas 

473
reservoirs which are analogous to CCS sites. There are some excellent examples 

of off-shore technologies for drilling through salt formations and shallow gas 

pockets that involve the same type of pressure issues that would be encountered 

in drilling through a CCS site. 

Individual Response: EPA acknowledges that technologies and past experience exist to inject 

through over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry 

experience in drilling through shallow pockets of gas or other zones that have higher pressures). EPA 

has reviewed information on these types of projects and has determined that, if properly constructed, 

wells can be drilled through pressurized zones without causing fluid movement. However, to provide 

additional USDW protection and ensure that any planned drilling is conducted appropriately, the final 

GS rule requires the Director to consider planned or permitted water, hydrocarbon, or mineral 

resource exploitation potential of the proposed injection formation and other formations both above 

and below the injection zone to determine if there are any plans to drill through the formation to 

access resources in or beneath the proposed injection zone/formation as specified in 

§146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 28565 

Comment: injection relative to the location of USDWs by proposing a waiver process. As 

stated in our December 24, 2008 Comments, we agree that CO2 can be injected 

above a USDW while protecting the USDW and maintaining access to the USDW for 

future use. As noted in our Comments, the Salt Creek EOR project in Wyoming, 

which has a USDW below the injection zone, is an excellent example of how 

industry can operate CO2 injection wells in an EOR context without endangering 

or limiting access to USDWs that are located below the injection zone. 

Accessing USDWs below a CCS site, while not trivial, does not present 

significant technological hurdles. Industry has the technology to drill through 

over-pressured gas reservoirs which are analogous to CCS sites. There are some 

excellent examples of off-shore technologies for drilling through salt 

formations and shallow gas pockets that involve the same type of pressure issues 

474
that would be encountered in drilling through a CCS site. 

Individual Response: EPA acknowledges that technologies and past experience exist to inject 

through over-pressured formations while maintaining zonal isolation (e.g., oil and gas industry 

experience in drilling through shallow pockets of gas or other zones that have higher pressures). EPA

has reviewed information on these types of projects and has determined that, if properly constructed, 

wells can be drilled through pressurized zones without causing fluid movement. However, to provide 

additional USDW protection and ensure that any planned drilling is conducted appropriately, the final 

GS rule requires the Director to consider planned or permitted water, hydrocarbon, or mineral 

resource exploitation potential of the proposed injection formation and other formations both above 

and below the injection zone to determine if there are any plans to drill through the formation to 

access resources in or beneath the proposed injection zone/formation as specified in 

§146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from lines 945 to 957, which is an excerpt from the previous 

section, lines 928 to 957. This comment appears twice in this report, once for each set of line 

numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 3430 3.4.3. Request for Information on Constructing Wells Through Existing 

CO2 Plumes (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28210 

475
Other EPA Comment Codes and Descriptions: 3420 3.4.2. Request for Information on Areas 

Where Injection Depth and USDWs Are a Concern (seeking comment) 

Comment: On the Appropriateness of Allowing CO2 Storage above a USDW and the related 

issue of who will regulate production wells that could intersect stored CO2? The 

overriding principle should be does the proposed Class VI rule help protect the 

wellbeing of humans and the health of the environment. Framing the issue in this 

way makes it clear that there is an explicit tradeoff being made about the use 

of USDWs for CO2 storage or the use of water bearing bodies that have more than 

10,000 TDS but are shallower than another formation which has waters with less 

than 10,000 TDS. This calls for a flexible and site- or region-specific approach 

that still includes mandatory criteria such as the presence of adequate caprocks 

above and below the proposed storage formation to ensure the protection of both 

shallower and deeper USDWs. 

Individual Response: EPA clarifies that the GS rule sets requirements for siting of GS projects, 

including the presence of adequate confining zones above (and where waivers are issued, below) the 

injection zone for the purpose of protecting USDWs from endangerment. EPA adds that the GS rule 

does not promote the use of any formations for GS over other uses. 

Finally, EPA clarifies that regulating production wells is outside the UIC program’s authority, but adds 

that the presence of production wells in the AoR of a Class VI well must be considered in the AoR and 

corrective action plan. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28211 

Comment: The USEPA should also explain in detail what authority it has (or needs to be 

given) to ensure that any future wells (oil, gas, water, injection) that drill 

through a formation which is being used for CO2 storage are built to withstand 

the higher pressures and acidity of these formations without becoming pathways 

for the migration of previously stored CO2 out of the target storage formation. 

476
If the USEPA has no way of regulating the construction of production wells that 

penetrate a CO2 storage formation and if it believes that it will not be granted 

this authority, then this needs to bear on decisions to allow storage in 

formations that are shallower than formations that might in the future be host 

to future water, oil or gas production wells that could penetrate the storage 

formation. The NODA asserts without elaboration "The management scheme will also 

ensure that there is a strategy developed to address future needs to access 

formations below the injection zone." (p. 44810) Without further elaborating how 

this would be done in practice, it would appear that the July 2008 proposed rule 

and the August 2009 NODA have yet to meaningfully address a key aspect of how 

injection above a USDW could be implemented safely. It is hoped that before this 

rule is finalized some clarity and specificity will be brought to this critical 

issue. 

Individual Response: EPA believes that, as part of its mission to protect current and future drinking 

water sources and to respond to public concerns about future drinking water resource availability it is 

appropriate to consider planned water, hydrocarbon, or mineral resource exploitation potential as part 

of a thorough site-specific evaluation of a proposed GS site. Therefore, to provide additional USDW 

protection and ensure that any planned drilling is conducted appropriately, the final GS rule requires 

the Director to consider planned or permitted water, hydrocarbon, or mineral resource exploitation 

potential of the proposed injection formation and other formations both above and below the injection 

zone to determine if there are any plans to drill through the formation to access resources in or 

beneath the proposed injection zone/formation as specified in §146.95(b)(1)(vii). 

EPA Team Member: 

Draft Status: 

Date Uploaded: 16-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 4000 4. Comments on Current State GS Activities (seeking comment) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

477
Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Nightingale 

Commenter Organization: Illinois Environmental Protection Agency (IEPA) 

EPA Letter ID: 0333 

EPA Comment ID: 28202 

Comment: IV. Current Illinois EPA activities addressing Geologic Sequestration ("GS") (pg 

44812) 

USEPA requested comment on current State activities addressing GS. At 

this time, the Illinois EPA is permitting geologic sequestration wells using the 

current Class I UIC regulations. 

Individual Response: EPA acknowledges that many states have already developed their own 

approaches to regulating GS. EPA believes that in many cases, these approaches will be compatible 

with EPA's final GS rule. The final GS rule, at §146.81(c), allows the construction of existing Class I, 

II, or V wells to be grandfathered, provided the owner or operator can demonstrate to the Director 

that the wells were engineered and constructed to meet the requirements at §146.86(a) and ensure 

protection of USDWs, in lieu of requirements at §146.86(b) and §146.87(a). EPA clarifies that, if these 

wells are determined to be acceptable for GS, they will be re-permitted as Class VI wells and will be 

subject to the operational, testing and monitoring, reporting, injection well plugging, and postinjection site care and site closure requirements in Subpart H of 40 CFR 146. If an owner or operator 

seeking to grandfather an existing Class I, II, or V well to a Class VI well cannot make this 

demonstration, then grandfathering of the constructed well will not be allowed. For additional 

information on the issue of grandfathering, please see the preamble to the final rule and responses to 

comments on the proposed GS rule. 

EPA Team Member: Cadmus--Natalie 

Draft Status: First 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28226 

Other EPA Comment Codes and Descriptions: 5700 5.14. Comments on Other Aspects of the 

Proposed Rule 

478
Comment: ROUNDTABLE SUGGESTIONS 

1. Respect State Primacy on SDWA Permitting. We believe that the Agency should 

be explicit in providing a reasonable process whereby states can obtain primacy 

over regulation of Class VI (CCS) wells. Many states already administer SDWA 

programs and have long experience regulating CO2 injection through Class II EOR 

programs. Further, a number of states are moving ahead with developing their 

own initiatives and regulations to solve other issues associated with CCS -- 

incentives provisions and provisions clarifying the nature of potentially 

affected property rights as two examples. As the Agency itself notes in its 

supplement: 

"The Agency is aware that States are currently in various stages of developing 

statutory frameworks, regulations, workgroups, technical guidance, and 

strategies for addressing CCS and GS. Much of the expertise and infrastructure 

currently exists within State UIC Programs. These programs will form the 

foundation for managing GS wells. Additionally, States can use multiple 

authorities beyond those afforded under the SDWA and UIC regulations including 

surface access and land rights, unitization of fields, pore space ownership, 

mineral rights, worker safety and emergency preparedness, and maximization of 

State oil and gas resource exploitation." 

Clearly, in determining state primacy, EPA will have to consider how to handle 

projects that span multiple states. We do not believe that issue to be 

insurmountable. Rules could include, for example, provisions for establishing a 

primary state for permitting purposes, with other affected states provided an 

opportunity for notice and comment. 

Such regulatory clarity is critically important, not only to states, but also 

project proponents, interested in early investment in major CCS projects. 

Individual Response: EPA agrees that states should be allowed to obtain primacy for Class VI wells 

independently of other well classes. EPA believes that allowing independent Class VI primacy may 

encourage states to take responsibility for implementation of Class VI regulations and provide for a 

more comprehensive approach to managing CCS projects by promoting the integration of GS activities 

under SDWA into a broader framework for managing CCS. Furthermore, GS operations involve 

ancillary activities (e.g., pipeline operations, pore space ownership, land use rights, and surface 

access) for which states can call upon other authorities that exist at the state level (but outside UIC 

authority) to provide a more comprehensive CCS management approach. In response to concerns 

about which state or region would oversee the permit for projects where the AoR spans state or tribal 

479
boundaries, EPA clarifies that issuance and oversight of a GS permit, including any associated AoR 

boundary-related coordination, is the responsibility of the primacy agency (State or Tribal) or regional 

DI program in the state where the injection well is located. EPA adds that the GS rule, at §146.82(b), 

requires that the Director notify representatives of all states, tribes, and territories in the AoR to 

inform them of the permit application and offer them an opportunity to be involved in any relevant 

activities, such as development of the required project-specific plans. For additional information on 

primacy, please see the preamble to the final rule and responses to comments on the proposed GS 

rule. 

EPA Team Member: Cadmus--Natalie 

Draft Status: 

Date Uploaded: 14-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28268 

Comment: d. State Progress 

The NODA seeks comment on "current State activities addressing GS," recognizing 

their pace- setting progress on CCS issues and its desire not to "unduly hinder" 

such progress. The NODA also mentions the "expertise and infrastructure" 

currently embodied in state programs. Of course, states have decades of 

experience and expertise dealing with the underground injection of CO2 in the 

EOR context, and, as NACCSA has previously commented, this experience and 

expertise should be maximized in the CCS context by allowing states substantial 

authority through delegated programs.[FOOTNOTE 4] Beyond the EOR context, 

however, and as the NODA notes, numerous states have made great progress in 

addressing the gamut of issues related to CCS, including issues related to 

property rights and long term assumption of/release from liability. 

FOOTNOTE 4: As previously noted, states should be given the option of obtaining 

primacy for only those well classes desired. A state with a history of primacy 

for Class II wells, for example, may want to parlay its experience and expertise 

into a Class VI program, but may not gain similar efficiencies if required to 

also accept primacy for other well classes with which it has little or no 

experience. Further, allowing primacy for Class VI wells alone would reward 

states for their foresight and action on CCS-related issues. NACCSA encourages 

the Agency to consider the states' solutions to these key issues in developing 

480
any comprehensive regulatory framework. 

Individual Response: EPA agrees that states should be allowed to obtain primacy for Class VI wells 

independent of other well classes. EPA believes that allowing independent Class VI primacy may 

encourage states to take responsibility for implementation of Class VI regulations and provide for a 

more comprehensive approach to managing CCS projects by promoting the integration of GS activities 

under SDWA into a broader framework for managing CCS. Furthermore, GS operations involve 

ancillary activities (e.g., pipeline operations, pore space ownership, land use rights, and surface 

access) for which states can call upon other authorities that exist at the state level (but outside UIC 

authority) to provide a more comprehensive CCS management approach. For additional information on 

primacy, please see the preamble to the final rule and responses to comments on the proposed GS 

rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28142 

Comment: d. State Progress 

The NODA seeks comment on "current State activities addressing GS," 

acknowledging that states have made great progress on this front and expressing 

its desire not to "unduly hinder" such progress. The NODA also references the 

"expertise and infrastructure" currently embodied in state programs and states’ 

abilities to bring clarity to CCS issues beyond those associated specifically 

with underground injection. The NODA suggests an approach that would give the 

states substantial authority under a delegated program (through 

primacy). [Footnote 15] 

[Footnote 15] See id. at 44812. 

States and tribes should play a key role in managing CCS projects and their 

decades of valuable experience regulating CO2 injection should be tapped as a 

resource. As the NODA notes, states have substantial authority to regulate 

481
aspects of CCS projects, such as issues related to property rights and financial 

incentives beyond injection and storage, and the Agency’s regulation on the 

latter can and should complement state action on the former. 

Individual Response: EPA acknowledges the expertise of state oil and gas agencies that have been 

regulating Class II wells for decades under section 1425 of SDWA. These agencies already understand 

many of the issues pertaining to Class VI wells and have experience with CO2 injection, subsurface 

operations, and pipeline transport, as well as familiarity with local interests and the SDWA. EPA 

assumes that this experience, along with the agencies’ familiarity with UIC permitting requirements, 

will help facilitate the adoption of Class VI primacy programs and assumes that many states with Class 

II programs will choose to have the Class II primacy agency implement the Class VI program. EPA 

believes that allowing independent Class VI primacy may encourage states to take responsibility for 

implementation of Class VI regulations and provide for a more comprehensive approach to managing 

CCS projects by promoting the integration of GS activities under SDWA into a broader framework for 

managing CCS. Furthermore, GS operations involve ancillary activities (e.g., pipeline operations, pore 

space ownership, land use rights, and surface access) for which states can call upon other authorities 

that exist at the state level (but outside UIC authority) to provide a more comprehensive CCS 

management approach. 

EPA Team Member: Cadmus--Natalie 

Draft Status: First 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28318 

Comment: The NODA seeks comments on current state activities addressing GS and seeks to 

avoid hindering progress states have made on this front. The NODA suggests an 

approach that would give the states substantial authority under a delegated 

program through primacy. EEI agrees that states and tribes have decades of 

valuable experience in this area and should play a key role in managing carbon 

capture and storage projects. In fact, states also have substantial authority to 

regulate aspects of carbon capture and storage in issues relating to property 

rights and financial incentives beyond injection and storage. However, it is 

482
Individual Response: EPA acknowledges the expertise of state oil and gas agencies that have been 

regulating Class II wells for decades under section 1425 of SDWA. These agencies already understand 

many of the issues pertaining to Class VI wells and have experience with CO2 injection, subsurface 

operations, and pipeline transport, as well as familiarity with local interests and the SDWA. EPA 

assumes that this experience, along with the agencies’ familiarity with UIC permitting requirements, 

will help facilitate the adoption of Class VI primacy programs. 

EPA Team Member: Cadmus--Natalie 

Draft Status: First 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text that is later repeated in lines 100 to 115. Part of this comment 

appears twice in this report, once for each set of line numbers. 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5000 5. Comments on the Proposed Rule (out of NODA Scope) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28204 

Other EPA Comment Codes and Descriptions: 1100 1.1 Comments on the Comprehensive 

Approach 

Comment: Completion of the proposed Class VI well rule should not be tied to the 

resolution of future US climate policy. The USEPA should also be commended for 

moving forward with the standalone proposed Class VI UIC rule even though there 

is a strong desire (and indeed a need) from many stakeholders to understand how 

this proposed Class VI rule would fit into a larger national climate change 

mitigation policy. While it is undoubtedly true that in a perfect world, it 

would be best if the nation’s future climate policy was fully articulated before 

the final Class VI rule were promulgated, we do not live in such a perfect 

483
world. And just as it is clear that the Class VI rule will need to be changed 

and revised over time as we learn more about commercial scale geologic CO2 

storage, it is also clear that the same kind of "adaptive regulatory approach" 

will be needed for the larger national climate policy as we learn more about the 

potential of various mitigation options as well as the extent and pace of 

negative climatic impacts. Therefore, it is wise to proceed with this rule as 

discussed in "Section II. What Did EPA Propose?" of the NODA (p. 44805). 

Individual Response: The Agency is using an adaptive approach to ensure USDW protection and 

meet the potentially fast pace of GS deployment. EPA believes that an adaptive approach will allow 

regulatory development to proceed in time to meet the current and future demand for Class VI 

permits while recognizing the need to continue to gather data from pilot projects and other research 

as it becomes available; as well as to enhance understanding of the technical and administrative 

aspects of GS deployment, operation, and technology developments. The Agency plans to collect and 

review data every six years on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary.

The issue of climate policy is outside the scope of the Notice of Data Availability and the UIC 

Program’s authority under the GS rulemaking. For more information on the GS requirements and the 

UIC program, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 28285 

Comment: CURC agrees with numerous assessments of climate mitigation strategies that 

conclude broad deployment of GS is an essential element of a strategy to achieve 

sharp reductions in greenhouse gas (GHG) emissions, such as those proposed in 

recent legislation before the U.S. Congress.[Footnote 2] 

[Footnote 2]: For example, both HR 2454 and the recent Kerry-Boxer draft 

legislation propose an 83% reduction in U.S. GHG emissions (relative to 2005 

484
emissions) by 2050. Separate EPA and DOE/EIA analyses each conclude that the 

cost of achieving the reductions specified in these bills is greatly increased 

if CCS technology is either unavailable, or significantly more costly to 

implement than currently projected. Other studies of global strategies conclude 

that CCS can reduce the marginal cost of meeting emission mitigations goals by 

approximately one-half (See Energy Technology Perspectives - 2008, Table 2.5, 

OECD/International Energy Agency, 2008). 

The potential utility of CCS technology in addressing global climate change is 

the basis for a global effort to demonstrate currently available technologies at 

commercial scale, while still conducting research and development to improve the 

technologies to make them more effective and affordable. EPA is faced with the 

challenge of ensuring that CO2 storage projects do not cause environmental 

damage to USDW, while not stifling the technology with unreasonably conservative 

regulation. 

CURC believes that the best way to do this is to provide State UIC Program 

Directors with a strong mandate to permit only injection wells which do not 

present a significant threat to USDW, and to develop tools and procedures to 

facilitate implementation of that mandate. Consistent with this philosophy, 

CURC opposes generic prohibitions of activities that, in the absence of much 

better data than is currently available, should be evaluated by the Program 

Director on a case-by-case basis. The prohibition related to injection depth 

included in the July 25, 2008, Notice of Proposed Rulemaking [Footnote 3] is 

such a requirement. 

[Footnote 3]: 73 FR 43492, July 25, 2008. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

485
EPA Letter ID: 0339 

EPA Comment ID: 28012 

Comment: D. SWRCB Closing Comments: 

There are hundreds of thousands of undocumented, abandoned wells and boreholes 

across US that are either not mapped or identified. These wells and boreholes 

are a conduit for CO2 to either escape to the atmosphere or to adjacent drinking 

water aquifers. To identify, map and properly destroy theses "artificial 

penetrations" before CO2 injection can take place is such a great task it 

borders on the impossible. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 18-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Patrick J. Nugent 

Commenter Organization: Texas Pipeline Association (TPA) 

EPA Letter ID: 0340 

EPA Comment ID: 28014 

Comment: of geologic sequestration. We encourage EPA to apply the site-specific assessment 

concept to issues beyond depth requirements. In our December 12, 2008 comments, 

we urged EPA to apply a site-specific, case-by-case approach to the following 

additional regulatory requirements: 

-the length of the post-closure period; 

-the required level of testing and monitoring; 

-whether tracers would be required to detect leaks; 

-whether down-hole automatic shut-off devices would be required; 

486
-the required level of financial assurance; and 

-requirements related to use of particular materials ~, corrosion-resistant 

materials vs. conventional materials). 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Emily Rochon 

Commenter Organization: Greenpeace International 

EPA Letter ID: 0342 

EPA Comment ID: 28028 

Comment: Permitting geological storage of CO2 under the SDWA is premature and incomplete 

Greenpeace would like to reiterate its concerns that any effort to regulate 

geological storage of CO2 under the SDWA is premature and incomplete. We 

understand EPA's motivation to create some sort of regulatory framework to 

permit this activity and appreciate the care the Agency has taken in drafting 

its proposed rules. However, the magnitude of the unknowns regarding 

underground storage of CO2 prevents the creation of a comprehensive and 

effective permitting regime at this time. Safe, permanent storage of carbon 

dioxide can not be assured; the techniques needed to adequately characterize and 

monitor storage locations are limited. There is no standard methodology that 

prescribes how a site must be characterized; no standard protocols or 

established network designs exist for monitoring and leakage; and no existing 

studies systematically estimate the probability and magnitude of CO2 release 

across a sample of geological storage systems. 

As such, the EPA should refrain from rushing to regulate that which is unknown. 

The storage of CO2 is not the only way to combat climate change and unless and 

until the environmental, public health and safety concerns are resolved, large 

scale projects should not be allowed. 

487
Another source of concern is that the SWDA is not of sufficient scope and 

enforceability to regulate this activity. Any regulatory regime enacted to 

permit this activity must, at a bare minimum, put standards in 

place that deal with matters such as ownership of stored CO2, liability, 

procedures for the detection and mitigation of leaks, verification of stored 

CO2, licensing of storage site operators and purity of the CO2 stream. While 

the SWDA does allow for the EPA to address some of these, it does not allow for 

a comprehensive approach to lay out a clear policy framework for the geological 

storage of CO2. Partial regulation of CO2 storage is inadequate at best and 

dangerous as well as costly to the public at worst. EPA should not enact 

regulations that are only able to partially address the substantial issues 

associated with pumping vast quantities of CO2 underground. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27891 

Comment: General The proposed rule is quite specific and seeks to compartmentalize 

comments only to the endangerment that may be caused to underground sources of 

drinking water (USDW). However, the proposal goes on to state that the Class VI 

injection wells are to be one approach "that could be deployed to reduce CO2 

emissions to the atmosphere and help to mitigate climate change." 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

488
EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28397 

Comment: Class VI well construction, operational, and monitoring requirements. We 

continue to advocate for performance-based standards over prescriptive 

requirements. GS is one of the essential technologies that could help to ensure 

that we can continue to produce the clean energy society demands. If you have 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

EPA Letter ID: 0360 

EPA Comment ID: 28238 

Comment: NRG appreciates the substantial efforts which have been part of this proposal 

development governing CO2 injection for the purpose of GS. As a company, NRG is 

committed to effectively addressing climate change, and believes that GS is a 

critical component for the reduction of CO2 emissions. In general, NRG supports 

and commends the efforts of the EPA to develop a rational approach that would 

(1) create a new category of injection wells (i.e., Class VI) under the 

Underground Injection Control (UIC) Program and (2) establish Federal 

regulations that are specifically tailored to CO2 injection for GS. NRG 

489
submitted comments last December on EPA’s proposal to regulate CO2 GS under the 

UIC program. See 73 Fed. Reg. 43492 (July 25, 2008). 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

EPA Letter ID: 0360 

EPA Comment ID: 28239 

Other EPA Comment Codes and Descriptions: 1000 1. General Comments on the Notice of Data 

Availability 

Comment: At the outset, NRG applauds EPA’s careful approach to the development of CO2 GS 

regulations, including this most recent release of additional data. Because the 

technology contemplated in the CO2 GS proposal will not be commercially deployed 

for many years, it is essential the Final Rule be flexible enough to accommodate 

developments in information and technology related to carbon sequestration. It 

is critical that EPA develop a regulatory regime incorporating performance-based 

standards in order to allow for site-tailored requirements that will reflect the 

vast differences among various potential CO2 GS sites. 

Individual Response: EPA believes that the final rule is based on the most recent GS-related data, 

information, and scientific research available. EPA intends to continue to collect data on GS and to 

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new 

research, data, and information about GS. The Agency believes that an adaptive approach provides 

Class VI owners or operators the flexibility to use and apply newly developed technologies for GS as 

they become available in the future. EPA plans to, every six years, collect and review data on GS 

projects to determine whether the appropriate amount and types of information and appropriate

documentation are being collected, and to determine if modifications to the requirements are 

appropriate or necessary.

490
EPA agrees with the commenter that a site-specific approach to permitting GS sites is important. The 

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a 

specific site and affords the Director flexibility to establish permit requirements on the basis of sitespecific characteristics. For additional information on the adaptive approach and site-specific 

requirements, see the responses to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 30-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Michael Moore 

Commenter Organization: North American Carbon Capture and Storage Association (NACCSA) 

EPA Letter ID: 0362 

EPA Comment ID: 28257 

Comment: II. General Principles and Summary of Key Points 

NACCSA applauds the Agency's initiative and continued efforts to bring 

regulatory certainty to the GS context as evidenced by the Agency's proposed UIC 

rules. As noted in the Preamble to the proposed rules, CCS holds the promise of 

storing large volumes of carbon dioxide in geologic formations such as deep 

saline formations, depleting and depleted oil & natural gas reservoirs, 

unmineable coal seams and similar geologic structures, and thus can play a 

central role as an emissions mitigation tool. Additionally, NACCSA members view 

carbon dioxide as a central component in the enhanced recovery of oil and 

natural gas and recognize that it is capable of being responsibly stored as part 

of this process. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

491
Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28274 

Comment: APS strongly supports aggressive research and development of viable methods for 

carbon capture and sequestration (CCS) projects and for reuse CO2 from fossil 

generation plants. EPA predicts that the electric power sector "will most likely 

be the largest potential market for [CCS] technologies," and predicts that CCS 

technology could lead to CO2 reductions of approximately 80-90% at a single 

plant. 73 Fed. Reg. 44354, 44492 (July 30, 2008). As a result of our involvement 

in this research and because of the potential for impact to our industry APS 

believes we have the knowledge and perspective to provide meaningful comments on 

the development of EPA's UIC regulations for CO2 geologic sequestration. 

APS appreciates EPA's careful approach to the development of the C02 geologic 

sequestration regulations, including this most recent release of additional 

data. Because the technology is still being developed and may not be 

commercially deployed for many years, it is essential that the rule be flexible 

in order to accommodate later developments in information and technology. 

Performance based standards allow for requirements that can be tailored for the 

differences in geology and other site characteristics across the country. 

Individual Response: The final rule is based on the most recent GS-related data, information, and 

scientific research available. EPA intends to continue to collect data on GS and to incorporate such 

data as it implements its adaptive approach to GS rulemaking. EPA plans to, every six years, collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary.

For additional information on the adaptive approach and site specific requirements, see the responses 

to comments on the proposed rule in the rulemaking docket.

The other portion of this comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside 

the scope of the Notice of Data Availability. Please see responses to comments on the proposed rule 

for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

492
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Stroben 

Commenter Organization: Duke Energy Corporation 

EPA Letter ID: 0368 

EPA Comment ID: 27927 

Comment: As one of the largest coal-fired generators of electricity in the U.S., and as a 

likely user of GS to reduce CO2 emissions, this rulemaking will have a direct 

impact on Duke Energy and its customers. In its December 22, 2008 comments on 

EPA's July 25, 2008 proposed "Federal Requirements Under the Underground 

Injection Control (UIC) Program for Carbon Dioxide (CO2) Geologic Sequestration 

(GS) Wells," Duke Energy encouraged EPA to provide flexibility and avoid a onesize-fits-all approach by incorporating performance-based standards into the 

final rule that would allow for site-specific project design, monitoring and 

closure. Duke Energy further stated in its comments that because the technology 

associated with large scale injection and storage of CO2 associated with 

electricity generation is still developing, EPA should provide flexibility by 

designing the UIC program for GS of CO2 so the program requirements can evolve 

along with the technology over time rather than lock-in regulatory requirements 

that will likely become obsolete. 

Individual Response: The final rule is based on the most recent GS-related data, information, and 

scientific research available. EPA intends to continue to collect data on GS and to incorporate such 

data as it implements its adaptive approach to GS rulemaking. EPA plans to, every six years, collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

For additional information on the adaptive approach and site specific requirements, see the responses 

to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Thomas Curtis 

Commenter Organization: American Water Works Association (AWWA) 

493
EPA Letter ID: 0369 

EPA Comment ID: 27933 

Comment: This letter details the comments of the American Water Works Association (AWWA) 

on the Notice of Data Availability (NODA) on the proposed requirements for 

carbon dioxide geosequestration wells under the Underground Injection Control 

(UIC) Program as published in the August 31st Federal Register (73 FR 44802). 

As we have stated in our previous comments on the proposed rule, protection of 

underground sources of drinking water (USDWs) should be a key priority of any 

geologic carbon sequestration (GS) regulation developed as part of the 

Underground Injection Control (UIC) Program. AWWA appreciates the opportunity 

to comment on this NODA, and we would like to reiterate five central issues that 

we feel should be addressed in the final regulation: 

- Protection of underground sources of drinking water (USDWs) should be the 

highest priority - water should trump everything; 

- If USDW water quality is degraded by a GS project, the owner/operator of that 

project must be fully responsible for any costs born by drinking water utilities 

due to increased treatment or other mitigation requirements for that ground 

water or replacement of lost capacity in perpetuity; 

- Prevention of unintended consequences is of utmost importance; 

- Injection of carbon dioxide should not be permitted above and/or between USDWs; 

- Injection of carbon dioxide and construction of injection wells should not be 

permitted in or near sole source aquifers, coal seams, earth-quake prone areas; 

and, 

- Hydraulic fracturing should not be used at all for GS. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

Please see the remainder of EPA's response to this comment for additional responses and on the 

injection depth waiver approach at §146.95. 

EPA Team Member: 

Draft Status: 

494
Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mike Smith 

Commenter Organization: Questar Exploration & Production Company 

EPA Letter ID: 0374 

EPA Comment ID: 28120 

Comment: implementation of GS in appropriate areas. Along those lines, Questar wishes to 

reinforce that the general well construction and operation requirements set 

forth in the proposed rules do not incorporate the lessons learned from 

industry's long-term implementation of enhanced oil and gas recovery, and will 

ultimately make it more difficult to employ GS without providing the additional 

safety benefits one would expect from adopting the more onerous Class I 

hazardous well construction and operating requirements that EPA is proposing. 

The lessons we have learned from EOR activities can and should be applied as EPA 

moves forward with its rulemaking. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27956 

Comment: Comment No. 5 

Page 44805 

Issue Topic from EPA's NODA 

495
EPA's Office of Research and Development is conducting intramural and extramural 

research activities to develop modeling and monitoring tools for protecting 

underground sources of drinking water. 

Carbon Sequestration Council Comments 

Monitoring and modeling needs will be different for each potential CO2 storage 

site, and we encourage flexibility in the model requirements. EPA should not be 

prescriptive in requiring certain models or monitoring techniques, as each 

storage site and the operational experience for each GS project will be 

different. Moreover, existing and future work may yield improved and alternative 

approaches to modeling for particular circumstances. 

Comment No. 6 

Page 44805 

Issue Topic from EPA's NODA 

Analytic and semi-analytic models are being developed and evaluated for 

determining the area of review based on geologic and hydrologic conditions. 

Carbon Sequestration Council Comments 

Same comment as in 5 above. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

496
EPA Letter ID: 0541 

EPA Comment ID: 28328 

Comment: injection above the lowermost USDW. API is still concerned, though, that by 

being overly prescriptive in designing the new well class that the proposed rule 

will hinder the deployment of CCS and could have the unanticipated consequence 

of hindering the innovations that could improve both well security and 

performance. CCS is one of the essential technologies that could help to ensure 

that we can continue to produce the clean energy society demands. API will be 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 14-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5050 5.1. Comments on the Proposed Permit Application Information (146.82) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28230 

Comment: As EPA itself has acknowledged, the geologic variability involved in different 

conceivable GS projects needs to be taken into account. We believe it needs to 

be factored into a whole range of issues ranging from site characterization, to 

497
area of review, to containment requirements. The regulations should encourage 

site-specific, performance-based determinations at the permitting stage to 

handle these important issues. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28255 

Comment: Page 43536- section 145.82- Require Class VI permit information 

In (b) it is indicated that only information of public record is required to be 

on the map. ALL known information public and confidential should be required to 

be on the map. There may mineral exploration drill holes or mapping that shows 

significant open shear zones or faults that may allow migration from the 

injection zone to the fresh water aquifers. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

498
EPA Letter ID: 0366 

EPA Comment ID: 27918 

Comment: Rules Subpart H Criteria and Standards (CFR 146) 

146.82 (b) Required permit Information 

DEQ suggests a modification to this section stating "the map will also show 

faults". Section 146.82(b) requires a map showing the injection wells and the 

applicable area of review, while section 146.82 (c) to (d) describes "data 

obtained during logging and testing of the well formation". The last sentence 

in 146.82(b) should perhaps only state that information of public record is 

required to be included on this map [section 146.82 (b)], and then note that the 

requirements for maps and geological systems information in 146. 82 (c) to (d) 

are different. Derived data and supplemental data should also be discussed in 

association with the site assessment. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5100 5.2. Comments on the Proposed Siting Requirements (146.83) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

499
Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28059 

Comment: (a) Minimum Criteria for Siting - The owner or operator must have demonstrated 

to the satisfaction of the Director that existing wells are, and new wells will 

be, sited in areas with a suitable geologic system. The geologic system must be 

comprised of: 

(1) An injection zone of sufficient areal extent, thickness, porosity, and 

permeability to receive the total anticipated volume of the carbon dioxide 

stream; 

(2) A confining zone(s) that is laterally continuous and free of known 

transmissible faults or fractures over an area sufficient to prevent the movement 

of fluids that endangers an USDW; 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28228 

Comment: We still believe that the most efficient way to proceed is with a tiered set of 

site characterization requirements based on demonstrable and known site 

characteristics. For example, potential sites that are deep saline formations 

located one or more kilometers below the ground surface are generally recognized 

as among the most favorable and secure site options for assuring public safety. 

If such sites do not have USDW aquifer located between it and the ground surface 

above, a more streamlined regulatory site characterization and risk review may 

be appropriate. 

500
On the other hand, an example of a potential site that may require a more 

rigorous site characterization and risk assessment are "sole source aquifers" 

which are aquifers that are the sole supply of water for a region and are 

critically important to protect. We believe that EPA’s proposed standards, with 

the waiver process included , make sense in these sensitive areas. EPA should 

still allow the permiting of Class VI wells in more sensitive areas, if it can 

be shown that there are sufficient caps and protections to prevent the migration 

of CO2 in overlying aquifers, even in proximity to aquifers designated as sole 

source. An early detection monitoring program could be established to provide 

sufficient opportunity to mitigate any unlikely release of CO2 from geologic 

storage unit. 

Such a tiered approach would allow EPA to achieve some streamlining UIC 

regulations for site characterizations and permit UIC Class VI wells that first 

and foremost protect public safety, yet reflect a workable balance in adapting 

site characterization and risk assessments based on criteria adaptable to unique 

candidate sites. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28251 

Comment: Proposed technical criteria for permitting geological sequestration wells 

The following comments are on the July 25,2008 proposed rules under 40 CFR Parts 

144 and 146 Geologic Sequestration (GS) Wells. 

Pages 43505 to 43506- Proposed Geologic Siting Requirements 

501
There are no minimum criteria for either the thickness or the permeability of 

the confining zone. Although there may be some rationality in lithified (solid 

rock) formations, in unconsolidated coastal plain formations the thickness and 

permeabilities are critical. In the New Jersey Coastal Plain there are many pump 

tests that demonstrated effects on overlying aquifers even when separated by 50 

feet of less than lE-08 clay. Note the permeability should be for the CO2 in the 

state being injected, gaseous or super critical CO2. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5150 5.3. Comments on the Proposed AoR and Corrective Action Requirements 

(146.84) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28060 

Comment: (1) The area of review is based on computational modeling, as well as monitoring 

and other operational data, that considers the volumes and the physical and 

chemical properties of all phases of the injected carbon dioxide stream. 

502
(2) The owner or operator must prepare, maintain, and comply with a plan to 

delineate the area of review for a proposed geologic sequestration project under 

this section, reevaluate the delineation, and perform corrective action that 

meets the requirements of this section in a manner and at a frequency acceptable 

to the Director. As a part of the permit application or revision, the owner or 

operator must submit an area of review and corrective action plan that includes 

the following information: 

(i) The method for delineating the area of review that meets the requirements of 

§146.25(b)(1) and (3), including the model to be used, assumptions that will be 

made, and the site characterization and other data including any existing 

monitoring data on which the model will be based; 

(ii) A description of: 

(A) How monitoring and operational data (e.g., injection rate and pressure) will 

be used to inform an area of review reevaluation; and Multi-Stakeholder 

Discussions (B) How corrective action will be conducted to meet the requirements 

of §146.25(b)(4), including what corrective action will be performed prior to 

injection and what, if any, portions of the area of review will have corrective 

action addressed on a phased basis and how the phasing will be determined; how 

corrective action will be adjusted if there are changes in the area of review; 

and how site access will be assured for future corrective action. 

(3) The owner or operator must perform the following actions to delineate the 

area of review and identify all wells that require corrective action: (i) 

Project, using computational modeling and available monitoring data, the 

projected lateral and vertical migration of the carbon dioxide plume and 

formation fluids in the subsurface from the commencement of carbon dioxide 

injection activities until the plume movement ceases or pressure differentials 

sufficient to cause the movement of injected fluids or formation fluids into an 

USDW are no longer present. The model must: 

(A) Be based on detailed geologic data collected to characterize the injection 

and confining zones, available monitoring data, and on anticipated operating 

data, including injection pressures, rates and total volumes over the duration 

of injection; 

(B) Take into account relevant geologic heterogeneities, and data quality, and 

their possible impact on model projections; 

503
(C) Consider potential migration through faults, fractures, and artificial 

penetrations and beyond lateral spill points; and 

(D) Consider the physical and chemical properties of all injected and formation 

fluids in the subsurface. 

(ii) Using methods approved by the Director, identify all known or reasonably 

discoverable artificial penetrations into the confining zone, including active, 

inactive and abandoned wells and underground mines, in the area of review that 

may penetrate the confining zone. Provide a description of each well’s type, 

construction, date drilled, location, depth, record of plugging and/or 

completion, and any additional information or evaluations the Director may 

require; and 

(iii) Determine which abandoned wells identified in §146.25(b)(3)(ii) have been 

plugged in a manner that prevents the movement of carbon dioxide or displaced 

formation fluids that may endanger USDWs; 

(iv) Determine which active and inactive wells identified in §146.25(b)(3)(ii) 

have been completed in a manner that prevents the movement of carbon dioxide or 

displaced formation fluids that may endanger USDWs. 

(4) The owner or operator must perform corrective action using materials 

suitable for use with the carbon dioxide stream on all wells identified in 

§146.25(b)(3)(ii) that are determined to need corrective action in accordance 

with 146.25(b)(2)(ii)(B). 

(5) (a) Notwithstanding the requirement in subparagraph (2)(i) of this paragraph 

to perform a reevaluation of the area of review at the frequency set forth in 

the area of review and corrective action plan, the owner or operator must also 

conduct the following whenever warranted by material change in the monitoring 

and operational data or in the evaluation of the monitoring and operational data 

by the owner or operator: 

"(i) reevaluate the area of review by performing all of the actions specified in 

subparagraphs (3)(i) through (iii) of this subsection to delineate the area of 

review and identify all wells that require corrective action; 

"(ii) perform corrective action on wells requiring corrective action in the 

reevaluated area of review in the same manner specified in paragraph (4) of this 

504
subsection; and 

"(iii) submit an amended area of review and corrective action plan or 

demonstrate to the Director through monitoring data and modeling results that no 

change to the area of review and corrective action plan is needed. 

"(b) Except as provided in subparagraph (c) of this subsection, the owner or 

operator shall also conduct a reevaluation by performing all of the actions 

specified in clauses (i)(A) through (C) of this subsection: 

"(i) Within the time periods specified in the area of review and corrective 

action plan for conducting such a reevaluation of the area of review; or 

"(ii) If an area of review evaluation or reevaluation has not been performed 

pursuant to §146.84(c) and (d) for the geologic sequestration project during the 

preceding ten (10) years, then within six months after the passage of that 10- 

year period. 

"(c) The Director shall waive the requirement for a reevaluation pursuant to 

either §146.25(5)(b)(i) or (ii) if the owner or operator demonstrates to the 

Director through monitoring and operational data and modeling results, such as 

those reviewed annually pursuant to section 146.25(m), that such a reevaluation 

is not warranted by material change." 

(6) The emergency and remedial response plan (as required by §146.25(l)) and a 

demonstration of financial responsibility (as required by §146.25(c)) must 

account for the entire area of review (as modified) regardless of whether or not 

corrective action in the area of review is phased. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

505
Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27912 

Comment: Area of Review 

The proposed standards require modeling and tracking of the actual CO2 plume and 

pressure front, with periodic re-evaluation of the modeled behavior as 

additional local experience is gained with a GS project. We acknowledge that 

modeling is a good method of predicting the behavior of injected CO2 but should 

not be relied upon without monitoring to verify the accuracy of the modeled 

predictions. Modeling should be continually refined throughout the life of a 

sequestration project. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27919 

Comment: 146.84(a) Area of review and corrective action 

This section states "that the area of review is based, in part, on computational 

modeling." we would like to know how many types of modeling exist and what 

the industrial standards or guidance is for the models. Relying on a computer 

model without detailed geological data is not adequate. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

506
EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5200 5.4. Comments on the Proposed Financial Responsibility Requirements 

(146.85) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Anonymous9 

Commenter Organization: 

EPA Letter ID: 0335 

EPA Comment ID: 28215 

Comment: Liability should be retained by generators and operators. Doesn't the fact that 

they're so eager to divest themselves of liability give you a clue as to how 

safe they think it is? It is high time the costs associated with coal-fired 

electricity stopped being subsidized with taxpayer dollars!! 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text that is later repeated in lines 25 to 26. Part of this comment 

appears twice in this report, once for each set of line numbers. 

507
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27898 

Comment: · Liability issues must be clarified in regard to human welfare and 

environmental protection rather than ensuring the financial viability of the 

commercial entities of power plants, pipeline, and well operators. Proponents 

wish to diminish liability for CCS and GS activities (EPA-HQOW-2008-0390-0150.1) and EPA must explicitly recognize the threat of an 

uncontrolled release of CO2 to human life. Acknowledgement of the potential 

hazard, in a manner similar to OSHA guidelines on "gases, vapors, fumes, dusts, 

and mists - 1926.55" would be beneficial. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27900 

Comment: · Financial Assurance should be required for any unforeseen effects of a given 

project. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

508
Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28061 

Comment: (c) Financial Assurance 

(1) The owner or operator must demonstrate the adequacy of existing financial 

responsibility or provide and maintain financial responsibility and resources 

for: corrective action (that meets the requirements of § 146.25 (b)), injection 

well plugging (that meets the requirements of § 146.25(j)), and post-injection 

site care and site closure (that meets the requirements of § 146.25 (k) and 

emergency and remedial response (that meets the requirements of § 146.25(l) in a 

manner prescribed by the Director until: 

(i) The Director receives a well plugging report identified in §146.25(j)(4) or 

completion of the post-injection site care and site closure plan as appropriate; 

and 

(ii) The Director determines that the site has reached the end of the postinjection site care period. 

(2) The owner or operator must provide to the Director, at a frequency 

determined by the Director, but no more frequently than annually, written 

updates or adjustments up or down to the cost estimate to account for any 

changes to the area of review and corrective action plan (§146. 25(b)(2)), the 

injection well plugging plan (§146. 25(j)(2)), and the post-injection site care 

and site closure plan (§146. 25(k)(1)) and for actions taken or changes in 

conditions that reduce the estimated costs of such plans. 

(3) The owner or operator must notify the Director of adverse financial 

conditions that may affect the ability to carry out injection well plugging and 

post-injection site care and site closure. 

(4) The owner or operator must provide an adjustment of the cost estimate to the 

509
Director if the Director has reason to believe that the most recent 

demonstration is no longer adequate to cover the cost of injection well plugging 

(as required by §146. 25(j)) and post-injection site care and site closure (as 

required by §146. 25(k)). 

(5) In conjunction with the submission under (c)(2) and (m), the owner or 

operator may request, and the Director may approve, an adjustment to the 

financial responsibility required by (c)(1) to account for actions or changes in 

conditions that have reduced the estimated costs of the plans referenced in (c) 

(1). 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28219 

Comment: The Roundtable strongly supports the aggressive research and development efforts 

underway to facilitate CO2 capture and sequestration ("CCS") projects. Among 

the biggest impediments to commercial-scale CCS projects today is regulatory 

uncertainty. Meaningful investments in CCS will only occur in the presence of 

clear, carefully tailored regulatory constructs that help encourage early and 

robust development of projects and which aid in eliminating liability risk for 

such early action. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

510
Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27916 

Comment: Financial Assurance 

Financial assurance accounts funded with real assets must be required as with 

other environmental programs (e.g., RCRA). Financial tests and self insurance 

are of no value if a company becomes financially insolvent. Financial assurance 

is only of value if the assets remain in the account after a company's financial 

demise. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5250 5.5. Comments on the Proposed Construction Requirements (146.86) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

511
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27862 

Comment: The Agencies do not look at the difficult research such as. what are the correct 

tubular materials to use for long term CO2 sequestration? The Agencies simply 

say casing and tubing was run, meaning they ran standard carbon steel tubulars, 

which are aggressively attached by wet CO2. This is a sorry way to spend tax 

payers’ money. The authors of some of the references are full time providers of 

reports supporting geological sequestration, since it is their means of making a 

living. EPA presses on, even as each day brings revelations of the incoherence, 

habits and excess of their plan. 

http://www.americanthinker.com/2009/08/global_warming_blues.html 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28062 

Comment: (d) Well Construction Requirements 

(1) Applicability 

(i) the requirements of this subsection apply to newly drilled injection wells 

and any existing well except to the extent the well is exempted pursuant to (ii) 

(ii) the Director may exempt an existing well from any of the provisions of (d) 

(2) if: 

512
(A) the well meets the construction requirements of 40 CFR 146.22; and 

(B) the Director determines, after evaluating the significance of any logs, 

surveys and tests which may be available for the well and the extent to which 

the well does or does not meet the provisions of (d)(2), that requiring the well 

to satisfy a particular provision is not necessary to avoid endangerment of an 

USDW. 

(2) Construction Requirements for newly-drilled injection wells. 

(i) General. The owner or operator must ensure that newly-drilled injection 

wells are constructed and completed to: 

(A) Prevent the movement of fluids into any unauthorized zones or an USDW as a 

result of the planned injection operation; 

(B) Permit the use of appropriate testing devices and workover tools; and 

(C) Permit continuous monitoring of the annulus space between the injection 

tubing and long string casing. 

(ii) Casing and cement or other materials used in the construction of each well 

to which this section is applicable must have sufficient structural strength and 

be designed for the life of the well. All well materials must be compatible with 

fluids with which the materials may be expected to come into contact and meet or 

exceed test standards or practices developed for such materials by the American 

Petroleum Institute, ASTM International, or comparable standards acceptable to 

the Director. The casing and cementing program must be designed to prevent the 

movement of fluids that endangers USDWs. In order to allow the Director to 

evaluate and approve casing and cementing requirements, the owner or operator 

must provide the following information: 

(A) Depth to the injection zone; 

(B) Hole size; 

(C) Size and grade of all casing strings (wall thickness, external diameter, 

nominal weight, length, joint specification and construction material); 

(D) Predicted corrosive characteristics of the combined carbon dioxide stream 

and formation fluids; 

513
(E) Down-hole temperatures and pressures; 

(F) Lithology of injection and confining zones; 

(G) Type or grade of cement and additives; and 

(H) Quantity, chemical composition, and temperature of the carbon dioxide 

stream. 

(iii) Casing must extend through the base of the lowermost USDW above the 

injection zone and be cemented to the surface. Cement may be staged. Surface 

casing need not extend through the base of the lowermost USDW above the 

injection zone if a combination of cement around the surface casing and 

intermediate or long-string casing achieves continuous cement through the base 

of the lowermost USDW above the injection zone. 

(iv)At least one long string casing, using a sufficient number of centralizers, 

which at a minimum must be sealed from within the injection zone upward through 

the overlying confining zone, and must provide adequate isolation of the 

injection zone and other intervals as necessary for protection of USDWs using 

cement and/or other isolation techniques. The Director may approve the use of 

packers or alternative isolation techniques, provided these are demonstrated to 

be equivalent to cement or more effective to provide adequate isolation and to 

protect USDWs. 

(v) Cement and cement additives must be suitable for use with the carbon dioxide 

stream and formation fluids and of sufficient quality and quantity to maintain 

integrity over the life the well. The integrity and location of the cement shall 

be verified using technology capable of evaluating cement quality and 

identifying the location of channels to ensure that USDWs are not endangered. 

(vi) Tubing and packer. 

(A) Owners and operators must inject fluids through tubing with a packer set at 

a depth opposite a cemented interval at the location approved by the Director. 

(B) In order to allow the Director to evaluate and approve tubing and packer 

requirements, the owner or operator must provide the following information:: 

(1) Depth of setting and the depth of the injection zone; 

514
(2) Composition of the carbon dioxide stream. 

(3) Maximum proposed injection temperature and pressure; 

(4) Maximum proposed annular pressure; 

(5) Maximum proposed injection rate (intermittent or continuous) and volume of 

the carbon dioxide stream; 

(6) Size of casing; and 

(7) Tubing tensile, burst, and collapse strengths. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28252 

Comment: Pages 43598 to 43510- Proposed Injection Well Construction Requirements 

Some states such as New Jersey have well construction requirements which are 

stricter than the oil industry standards, and in those cases the state 

regulations should be followed down through all of the fresh water aquifers into 

the confining layer above the target zone. New Jersey requires a 2 inch annulus, 

and generally the oil industry requires a 1 inch annulus. New Jersey has a 

standard for the maximum permeability of a grout. New Jersey requires the entire 

annulus be grouted to the surface. In the coastal areas where there is potential 

for salt water intrusion into underlying aquifers from shallow saline aquifers 

there is a requirement that the well be double-cased with all annuluses 

515
permanently sealed. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28256 

Comment: Page 43537- section 146.86- Injection well construction requirements 

The injection and monitoring wells should meet the state standards down through 

all freshwater zones if the state standard is more stringent than the federal 

standard. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27913 

516
Comment: Well Standards 

We believe the proposed well construction standards may be difficult or 

impossible to meet in some geologic settings. The standards require a surface 

casing installed to the lowermost USDW and cemented to the surface. In geologic 

settings with bedrock and deep drinking water quality aquifers, it may be 

difficult to set the surface casings this deep. Oregon's Columbia River basalts 

may be as deep as 10,000 feet and much of that depth with drinking water quality 

groundwater. The multiple flows and fractures in these beds make for difficult 

drilling and frequently require setting intermediate casings. The standards 

should allow a protective casing program that can be reliably installed in all 

geologic settings. Deep aquifers may provide the most protective geologic 

settings for CO2 injection and the well construction standards should not discourage 

their use. 

Down hole valves and other required downhole equipment may impact or prevent 

certain monitoring techniques. It is important to require appropriate safeguards 

but leave some flexibility to use new technologies as new methods are developed. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27920 

Comment: 146.86(b) (3) Well construction 

We interpret this regulation to imply that wells can be grouted with cement in one 

or more stages. The problem with cementing in stages is that it is possible to 

have cold joints that may allow the movement of water or other fluids within the 

annual space. We would prefer that the grout be placed in one continuous 

517
operation without a significant interruption. By that we mean that the grout 

should not be allowed to set up to a point that a cold joint would be created 

when continuing to place grout after an interruption of over 72 hours if 

Portland Cement is used, 48 hours if High Early Strength Type III Portland 

Cement is used, or 6 hours if high Alumina Cement is used. Other interruption 

times would vary depending upon the final set time of the proposed grout. We also 

suggest it be required for continuous cementing to take a minimum amount of 

grout to complete the seal. For example, the rules should require that a 

minimum of 120% to 130% of the estimated volume of sealing material be used when 

sealing. While this would not guarantee an adequate seal, the chances of a 

sufficient seal would be greater with the appropriate amount of grout. Too 

little grout raises a red flag. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5300 5.6. Comments on the Proposed Logging, Sampling, and Testing 

Requirements (146.87) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28063 

518
Comment: (e) Logging, sampling, and testing prior to new well operation – The following 

requirements apply only to newly-drilled wells. 

(1) During the drilling and construction of an injection well, the owner or 

operator must run appropriate logs, surveys and tests to determine or verify the 

depth, thickness, porosity, permeability, and lithology of, and the salinity of 

any formation fluids in, all relevant geologic formations to evaluate 

conformance with applicable injection well construction requirements and to 

establish accurate baseline data against which future measurements may be 

compared. The owner or operator must submit to the Director a descriptive report 

prepared by a knowledgeable log analyst that includes an interpretation of the 

results of such logs and tests. The Director may approve such additional or 

alternative logs and tests as may be requested by the owner or operator after 

taking into account the availability of similar data in the area of the drilling 

site, the construction plan, and the need for additional information as the 

construction of the well progresses and these may include the following: 

(i) Deviation checks during drilling must be at sufficiently frequent intervals 

to determine the location of the borehole; 

(ii) In conjunction with installation of the surface casing: 

(A) Resistivity, gamma ray, and caliper logs before the casing is installed; and 

(B) Cement evaluation log(s) after the casing is set and cemented and/or map(s) 

to evaluate cement quality with sufficient radial resolution to identify 

channels or missing cement that would prevent compliance with §146.25(d)(2). 

(iii) Before and upon installation of the long string casing: 

(A)Resistivity, spontaneous potential, porosity, caliper, gamma ray and any 

other logs the Director requires based on site specific conditions and riskbased factors for the given geology before the casing is installed; and 

(B) Cement evaluation log(s) after the casing is set and cemented and/or map(s) 

to evaluate cement quality with sufficient radial resolution to identify 

channels or missing cement that would prevent compliance with §146.25(d)(2). 

(iv) Test(s) designed to demonstrate the internal and external mechanical 

integrity of injection wells, which may include one or more of the following: 

519
(A) A pressure test with liquid or gas; 

(B) Oxygen-activation logging; 

(C) Tracer surveys; 

(D) A temperature or noise log; or 

(E) A casing inspection log. 

(v) Any alternative methods that provide reliable, equivalent or better 

information and that are required of and/or approved of by the Director. 

(2) The owner or operator must submit to the Director a report describing whole 

cores or sidewall cores representative of the injection zone and confining 

system and formation fluid samples from the injection zone(s). The Director may 

accept data from cores and fluid samples from nearby wells if the owner or 

operator can demonstrate that such data are representative of conditions in the 

well bore. 

(3) Prior to injection well operation, the owner or operator must record the 

ormation temperature, formation fluid pH and conductivity, and reservoir 

pressure of the injection zone(s). 

(4) At any time prior to injection well operation, the owner or operator must 

determine fracture pressures of the injection and confining zones and conduct 

tests to verify hydrogeologic and geomechanical characteristics of the injection 

zone as necessary to satisfy the requirements of (f)(1). 

(5) The owner or operator must provide the Director with the opportunity to 

witness all logging and testing required by this subpart. The owner or operator 

must submit a schedule of such activities to the Director upon spudding the well 

and submit any changes to the schedule 48 hours prior to the scheduled test. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

520
Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27921 

Comment: 146.87(b) Logging, sampling, and testing prior to operation 

This regulation states that the Director may accept cores from nearby wells if the 

owner/operator can demonstrate that core retrieval is not possible and that such 

cores are representative of conditions of the well. We believe that cores from 

nearby wells may not be indicative of the conditions at the well being 

constructed and thus if possible a down hole video should be made to accurately 

show the conditions at the well site. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5350 5.7. Comments on the Proposed Operating Requirements (146.88) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

521
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28064 

Comment: (f) Injection well operating requirements 

(1) The owner or operator must comply with a maximum injection pressure limit 

approved by the Director and specified in the permit. In approving a maximum 

injection pressure limit, the Director shall consider the results of well tests 

and, where appropriate, geomechanical or other studies that assess the risks of 

tensile failure and shear failure. The Director shall approve limits that, with 

a reasonable degree of certainty, will avoid initiation or propagation of 

fractures in the confining zone or cause otherwise non-transmissive faults 

transecting the confining zone to become transmissible. In no case may injection 

pressure cause movement of injection or formation fluids in a manner prohibited 

by 40 CFR §144.12(a). 

(2) Injection of the carbon dioxide stream into any annulus or between the 

outermost casing protecting USDWs and the well bore is prohibited. 

(3) The owner or operator must fill the annulus between the tubing and the long 

string casing with a corrosion inhibiting fluid approved by the Director and 

must maintain a positive pressure on the annulus. 

(4) The owner or operator must install and use continuous recording devices to 

monitor: the injection pressure and the rate, volume, and temperature of the 

carbon dioxide stream. The owner or operator must regularly monitor the 

pressure on the annulus between the tubing and the long string casing. The owner 

or operator must install, test and use alarms and automatic shut-off systems, 

designed to alert the operator and shut-in the well when operating parameters 

such as injection rate, injection pressure, or other parameters approved by the 

Director diverge beyond ranges and/or gradients specified in the permit. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

522
Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5400 5.8. Comments on the Proposed MIT Requirements (146.89) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28065 

Comment: (5) Mechanical integrity 

(i) A well has mechanical integrity if: 

(A) There is no significant leak in the casing, tubing or packer; and 

(B) There is no significant fluid movement into an USDW through channels 

adjacent to the injection well bore. 

(ii) To evaluate the absence of significant leaks under this subsection, owners 

or operators must, following an initial annulus pressure test, continuously 

monitor and record at least daily injection pressure, rate, injected volumes, 

and pressure on the annulus between tubing and long stem casing and annulus 

fluid volume as specified in §146.25(g)(2)(ii); 

(iii) At least once per year, the owner or operator must confirm the absence of 

significant fluid movement under paragraph (5)(i)(B) of this section using a 

method acceptable to the Director (e.g. including diagnostic surveys such as 

oxygen-activation logging or temperature or noise logs). 

523
(iv) The Director may require any other test to evaluate mechanical integrity 

under paragraph (i)(A) or (i)(B) of this section. Also, the Director may allow 

the use of a test to demonstrate mechanical integrity other than those listed 

above with the written approval of the Administrator. To obtain approval, the 

Director must submit a written request to the Administrator, which must set 

forth the proposed test and all technical data supporting its use. The 

Administrator must approve the request if it will reliably demonstrate the 

mechanical integrity of wells for which its use is proposed. Any alternate 

method approved by the Administrator will be published in the Federal Register 

and may be used in all States in accordance with applicable State law unless its 

use is restricted at the time of approval by the Administrator. 

(v) In conducting and evaluating the tests enumerated in this section or others 

to be allowed by the Director, the owner or operator and the Director must apply 

methods and standards generally accepted in the industry. When the owner or 

operator reports the results of mechanical integrity tests to the Director, 

he/she shall include a description of the test(s) and the method(s) used. In 

making his/her evaluation, the Director must review monitoring and other test 

data submitted since the previous evaluation. 

(vi) The Director may require additional or alternative tests if the results 

presented by the owner or operator under paragraph (d) of this section are not 

satisfactory to the Director to demonstrate that there is no significant leak in 

the casing, tubing or packer or significant movement of fluid into or between 

USDWs resulting from the injection activity as stated in paragraphs (i)(A) and 

(i)(B) of this section. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

524
EPA Letter ID: 0366 

EPA Comment ID: 27922 

Comment: 146.89 Mechanical integrity 

The term "significant" is often used when describing leaks. We propose there 

should either be a definition of significant or the wells should be adequately 

sealed so there are no leaks. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5450 5.9. Comments on the Proposed Monitoring Requirements (146.90) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28192 

Other EPA Comment Codes and Descriptions: 2120 2.1.2. SWP (Aneth Field, UT) 

Comment: 6. We support the requirement for project design with a "robust monitoring plan" 

that is capable of corroborating modeling with actual performance. This should 

include assessment of dissolution or dissociation and effects on the 

525
mobilization of trace elements. 

Individual Response: EPA agrees that GS project design requires a robust monitoring plan. An 

essential part of that monitoring plan must be obtaining data to validate computational model 

performance. The GS rule includes requirements at 146.90(d) for ground water monitoring for 

geochemical changes, which can be used to detect mobilization of metals and dissolution of CO2 in 

subsurface brine. See the response to comments document for the proposed rule for additional 

information on EPA’s final approach to monitoring for GS projects. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27885 

Other EPA Comment Codes and Descriptions: 2100 2.1 DOE Regional Carbon Sequestration 

Partnership Projects 

Comment: It is appropriate to test techniques such as tracers, surface air/soil gas 

monitoring and microseismic monitoring to determine their overall usefulness and 

effectiveness during this experimental period for CCS. The NODA's description of 

these projects, however, could be read to suggest that the Agency favors 

establishing requirements for the use of tracers, surface air/soil gas 

monitoring, and/or microseismic monitoring. Through EEI, AEP has previously 

advised against imposition of a requirement to use tracers or surface air/soil 

gas monitoring to detect movement of CO2, even where, as the Agency proposed, 

such a requirement is left to the UIC program director's discretion. In the case 

of tracers or surface air/soil gas monitoring, these technologies would likely 

provide too little information, too late, in terms of protecting USDWs, and the 

risk of "false positives" is high. With regards to microseismic monitoring, 

AEP's experience has raised concerns about its application to full-scale 

projects. Specifically, existing monitoring equipment has not proven reliable, 

and alternative sources of comparable equipment are not readily available. 

While the use of many technologies, including tracers, surface air/soil gas 

monitoring and microseismic monitoring may be appropriate and useful in the 

526
context of an experimental project, the Agency must keep in mind this context. 

The utility of such technologies in any given experimental context does not 

necessarily warrant their use in a commercial setting. Moreover, EPA must 

separate the utility of these technologies in the experimental context in 

further demonstrating the efficacy of storage from their potential utility as 

"leak detectors" during the operation of commercial CCS projects. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. EPA believes that a robust monitoring 

program is critical to ensuring protection of USDWs at GS projects from endangerment, but clarifies 

that the use of any monitoring technique in the pilot projects does not amount to an endorsement by 

EPA or an intent by EPA to require that particular method. By testing multiple technologies, the pilot 

sites provide valuable data that demonstrate whether or not these technologies are viable and inform 

the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring, 

and tracers are subject to variability and may not be appropriate or necessary in all settings. EPA also 

recognizes that seismic plume tracking may not be appropriate in all settings, e.g., in certain types of 

geologic formations. The final GS rule at 40 CFR 146.90 gives the Director discretion to determine 

what methods are appropriate. All monitoring must be performed according to the Director-approved 

testing and monitoring plan. See the response to comments document for the proposed rule for 

additional information on EPA’s final approach to monitoring at GS sites.

The testing and monitoring requirements for the GS wells at §146.90 incorporate elements of preexisting UIC requirements for monitoring and testing, tailored and augmented as appropriate for GS 

projects. EPA recognizes that much will be learned about monitoring and testing technologies and 

their application in various settings in the early phases of GS deployment. EPA plans, every six years, 

to collect and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary as part of the Agency’s adaptive rulemaking approach. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

527
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28066 

Comment: (g) Testing and Monitoring 

(1) Based on a site-specific assessment of the potential for fluid movement from 

the injection well or injection zone, and on the potential value of monitoring 

wells to detect such movement, the owner or operator of a well must prepare, 

maintain, and comply with a testing and monitoring plan to verify that the 

geologic sequestration project is operating as permitted and is not endangering 

USDWs. The testing and monitoring plan must be submitted with the permit 

application for Director approval, and must include a description of how the 

owner or operator will meet the requirements of this section. 

(2) The testing and monitoring plan must, at a minimum, include: 

(i) analysis of the carbon dioxide stream with sufficient frequency to yield 

data representative of its chemical and physical characteristics; 

(ii)Installation and use, except during well workovers as defined in section 

146.88(d), of continuous monitoring devices (including digital devices capturing 

periodic data) to monitor injection pressure, rate and volume; and to record at 

least daily the pressure on the annulus between the tubing and the long strong 

casing; 

(iii) demonstration of external mechanical integrity pursuant to §146.25(f)(5) 

until the well is plugged; 

(iv) monitoring of the pressure buildup in the injection zone annually, 

including at a minimum, a shut down of the well for a time sufficient to conduct 

a valid observation of the pressure fall-off curve at least once every five 

years; and 

(v) quality assurance provisions. 

(3) Where appropriate, the testing and monitoring plan shall also include: 

528
(i) Monitoring for pressure changes in an appropriately porous and permeable 

formation overlying the confining zone; 

(ii) The use of indirect, geophysical techniques to determine the position of 

the carbon dioxide stream front, the water quality in a designated formation, or 

to provide other site specific data; 

(iii) Periodic monitoring of water quality for constituents specified in the 

plan in an appropriately porous and permeable formation overlying the injection 

zone; 

(iv) Periodic monitoring of water quality for constituents specified in the plan 

in one or more USDWs; 

(v) Corrosion monitoring of the well materials that will come into contact with 

water for loss of mass, thickness, cracking, pitting and other signs of 

corrosion performed and recorded at least quarterly which may be modified to be 

less frequent as approved by the Director based on construction materials, 

operating conditions, and monitoring history to ensure that the well components 

meet minimum standards for material strength and performance by: 

(A) Analyzing coupons of the well construction materials placed in contact with 

the carbon dioxide stream; or 

(B) Routing the carbon dioxide stream through a loop constructed with the 

material used in the well and inspecting the materials in the loop; or 

(C) Using an alternative method, materials, or time period approved by the 

Director; 

(vi) Any additional monitoring, as required by the Director, based on sitespecific conditions and risk-based factors, necessary to support, upgrade, and 

improve computational modeling of the area of review evaluation required under § 

146.25(b)(2); and 

(vii) Any additional testing and monitoring necessary to determine whether fluid 

movement is occurring that would endanger an USDW. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

529
proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28253 

Comment: Pages 43514 to 43517- Proposed Plume and Pressure Front Monitoring Requirements 

At a minimum there should be a monitoring well set just above the confining layer 

at every site the injection zone has a monitoring well. There also should be a 

monitoring well above the confining layer at the site of the injection well. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27914 

Comment: Monitoring 

Direct monitoring of the formations immediately above the confining layer for a 

geologic sequestration injection zone is an important requirement for the early 

detection of unacceptable leakage or venting. The intent is to have no leakage 

or venting occur. Monitoring wells installed into these formations should be 

530
required for all projects. Geophysical methods and other indirect monitoring, 

while useful, should not be allowed to substitute for all direct monitoring 

above the confining layer. 

The number of wells drilled through the confining layer into the injection zone 

should be minimized as each new well represents a risk of establishing a pathway 

for the migration of C02 or in-situ fluids into shallower aquifers. Projects may 

be able to get sufficient monitoring data from injection wells to minimize the 

need for stand-alone injection zone monitoring wells. 

Decisions on the level of direct and indirect monitoring should be made on a 

site-by-site basis, based upon the geologic characteristics. Some direct 

monitoring must be required above the confining layer to confirm that indirect 

monitoring is accurate. 

Periodic corrosion and well integrity testing is important for all pollution 

prevention programs. This well testing will help operators to focus maintenance 

and repair activities on the wells that are degrading. It is better to prevent 

leakage from a well breach than to fix the well after discovering that it has 

leaked. We support adoption of requiring extensive corrosion controls with 

monitoring until more data is available on how cement will react long term with 

CO2. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Robert Voorhees 

Commenter Organization: Carbon Sequestration Council 

EPA Letter ID: 0382 

EPA Comment ID: 27957 

Comment: Page 44805 

531
Issue Topic from EPA's NODA 

Comprehensive laboratory tests are being applied to the development and fieldtesting of monitoring strategies that can detect migration of fluids into 

shallow aquifers and assess potential geochemical impacts. 

Carbon Sequestration Council Comments 

The proposed EPA regulation was drafted with the recognition that there is no 

one suite of monitoring tools that is appropriate for all potential 

sequestration sites. A variety of subsurface factors and location specific 

concerns need to be considered to develop the best monitoring strategy for a 

given project. There are many monitoring tools that could be shown to have some 

utility, but it does not follow that every tool - or any particular tool - 

should be used or required for any given geological storage project, especially 

as scaling-up some of these monitoring techniques from pilot to commercial scale 

would be cost-prohibitive. For example, soil and air monitoring are unnecessary 

under most foreseeable circumstances. The general strategy of monitoring 

programs should be to confirm the validity of the site selection and 

characterization process and to detect any leakage long before it reaches the 

surface. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28125 

Comment: In considering new data on GS projects, EPA must separate the utility of monitoring 

technologies, particularly 

the use of tracers and surface air or soil gas monitoring, in the experimental 

532
context in further demonstrating the efficacy of storage from their potential 

utility as "leak detectors" during commercial CCS operations. Permit writers 

need clear guidance on appropriate monitoring tools for commercial CCS projects, 

as well as sufficient funding to undertake appropriate review of applications. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28139 

Other EPA Comment Codes and Descriptions: 2100 2.1 DOE Regional Carbon Sequestration 

Partnership Projects 

Comment: It is appropriate to test techniques such as tracers and surface air/soil gas 

monitoring to determine their overall usefulness and effectiveness during this 

experimental period for CCS. The NODA’s description of these three projects, 

however, could be read to suggest that the Agency favors employing requirements 

for the use of tracers and/or surface air/soil gas monitoring. EEI has 

previously advised against imposition of a requirement to use tracers or surface 

air/soil gas monitoring to detect movement of CO2, even where, as the Agency 

proposed, such a requirement is left to the UIC program director’s discretion. 

In brief, these technologies would likely provide too little information, too 

late, in terms of protecting USDWs, and the risk of "false positives" is high. 

Requiring their use may create or encourage overly negative and unwarranted 

public perception regarding the safety of GS. Further, tracers may present 

their own safety concerns. Finally, the Agency’s authority under the SDWA to 

protect USDWs via these surface-level monitoring tools is not clear. 

While the use of many technologies, including tracers and surface air/soil gas 

monitoring, may be appropriate and useful in the context of an experimental 

project, the Agency must keep in mind this context. The utility of such 

533
technologies in any given experimental context does not necessarily warrant in 

favor of requiring their use in a commercial setting. Moreover, EPA must 

separate the utility of these technologies in the experimental context in 

further demonstrating the efficacy of storage from their potential utility as 

"leak detectors" during the operation of actual commercial CCS projects. As 

noted above, tracers will not provide sufficient information in an appropriate 

timeframe to allow for immediate remediation of any deficiencies in the 

injection well that may result in a CO2 leak. 

Individual Response: EPA acknowledges that the pilot sites studied involved extensive monitoring 

that may not necessarily be appropriate for all GS sites. However, EPA believes that a robust 

monitoring program is critical to ensuring protection of USDWs at GS projects from endangerment, but 

clarifies that the use of any monitoring technique in the pilot projects does not amount to an 

endorsement by EPA or an intent by EPA to require that particular method. By testing multiple 

technologies, the pilot sites provide valuable data that demonstrate whether or not these technologies 

are viable and informed the final GS rule about the appropriate use of monitoring technologies.

EPA acknowledges that the appropriate monitoring methods and technologies will be determined on a 

site-specific basis. Data from the projects presented supports the need for a site-specific monitoring 

plan that will allow use of a range of monitoring technologies suitable for each unique GS site.

EPA recognizes that certain monitoring technologies, particularly surface air and soil gas monitoring 

and tracers are subject to variability and may not be appropriate or necessary in all settings. The GS 

rule at 146.90 gives the Director discretion to determine what methods are appropriate. All monitoring 

must be performed according to the Director-approved testing and monitoring plan. See the response 

to comments document for the proposed rule for additional information on EPA’s final approach to 

monitoring at GS sites. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5500 5.10. Comments on the Proposed Reporting Requirements (146.91) 

EPA Team Member: 

Draft Status:

Date Uploaded: July 16, 2009 

Notes: 

534
Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28067 

Comment: (h) Reporting Requirements 

The owner or operator must, at a minimum, provide the following reports to the 

Director, for each permitted well: 

(1) Semi-annual or less frequently as determined by the Director reports 

containing: 

(i) Any significant changes to the physical, chemical and other relevant 

characteristics of the carbon dioxide stream from the proposed operating data; 

(ii) Monthly average, maximum and minimum values for injection pressure, flow 

rate and volume, and annular pressure; 

(iii) A description of any event that significantly exceeds operating parameters 

for annulus pressure or injection pressure as specified in the permit; (iv) A 

description of any event which triggers a shutdown device required pursuant to 

§146.25(f)(4) and the response taken; 

(v) The monthly volume of the carbon dioxide stream injected over the reporting 

period and project cumulatively; 

(vi) Monthly annulus fluid volume added; and 

(vii) The results of monitoring prescribed under §146.25(g). 

(2)Report, within 30 days the results of: 

(i)Periodic tests of mechanical integrity; 

535
(ii)Any other test of the injection well conducted by the permittee if required 

by the Director; and 

(iii) Any well workover. 

(3)Owners or operators must submit reports in an electronic format acceptable to 

the Director. At the discretion of the Director, other formats may be accepted. 

(4)The owner or operator must prepare, maintain, and update required plans in 

accordance with the provisions of this section. 

(i)Owners or operators must submit an annual statement, signed by an appropriate 

company official, confirming that the company has: 

(A)reviewed the monitoring and operational data that are relevant to a decision 

on whether to reevaluate the area of review and the monitoring and operational 

data that are relevant to a decision on whether to update a plan identified in 

§146.25(i)(16) or (20) through (23); and 

(B)determined whether any updates were warranted by material change in the 

monitoring and operational data or in the evaluation of the monitoring and 

operational data by the owner or operator. 

(ii)Owners or operators must submit either the updated plan or a summary of the 

modifications for each plan for which an update was determined to be warranted 

pursuant to subparagraph (i) of this paragraph. The Director may require 

submission of copies of any updated plans and/or additional information 

regarding whether or not updates of any particular plans are warranted. 

(iii) The Director may require the revision of any required plan whenever the 

Director determines that such a revision is necessary to comply with the 

requirements of this subchapter. 

(i) Required permit application information This section sets forth the 

information which the owner or operator must submit to the Director in order to 

be permitted. The application for a permit for construction and operation of an 

injection well or for authorization to operate an existing well must include the 

following: 

(1)Information required in 40 CFR 144.31(e)(1) through (6); 

536
(2)A surface map showing the proposed locations for the injection well(s) for 

which a permit is sought and the applicable area of review. Within the area of 

review, the map must show the number, or name and location of all known 

injection wells, producing wells, abandoned wells, plugged wells or dry holes, 

deep stratigraphic boreholes, State or EPA approved subsurface cleanup sites, 

surface bodies of water, springs, mines (surface and subsurface), quarries, 

water wells and other pertinent surface features including structures intended 

for human occupancy and roads. Only information of public record is required to 

be included on this map; 

(3)A map delineating the area of review based upon modeling, using all available 

data including data available from any logging and testing of wells. 

(4)Information on the geologic structure and reservoir properties of the 

proposed storage site and overlying formations, which may include: 

(i)Isopach maps of the proposed injection and confining zone(s), a structural 

contour map aligned with the top of the proposed injection zone, and at least 

two geologic cross sections of the area of review reasonably perpendicular to 

each other showing the geologic formations from the surface to total depth of 

the well. 

(ii)Location, orientation, and properties of known or suspected subsurface 

faults that may transect the confining zone(s) in the area of review and a 

determination that they would not interfere with containment; 

(iii) Information on seismic history that have affected the proposed area of 

review including knowledge of previous seismic events and history of these 

events, including the presence and depth of seismic sources and a determination 

that the seismicity would not compromise containment; 

(iv) Data sufficient to demonstrate the effectiveness of the injection and 

confining zone(s), including data on the depth, areal extent, thickness, 

mineralogy, porosity, vertical permeability reservoir pressure and of the 

injection and confining zone(s) within the area of review; including geologic 

changes based on field data which may include geologic cores, outcrop data, 

seismic surveys, well logs, capillary pressure tests and names and lithologic 

descriptions; 

(v) Geomechanical information representative of the confining zone(s) in the 

537
area of review, such as information on fractures, stress, ductility, rock 

strength, and in situ fluid pressures; and 

(vi) Geologic and topographic maps and cross sections illustrating geology, 

hydrogeology, and the geologic structure of the area of review. 

(5) A compilation of all artificial penetrations within the area of review which 

penetrate the injection or confining zone(s). Such data should include a 

description of each well’s type, construction, date drilled, location, depth, 

record of plugging and/ or completion, and any additional information the 

Director may require; 

(6) Maps and stratigraphic cross sections indicating the general vertical and 

lateral limits of all USDWs, the location of water wells and perennial springs 

within the area of review, their positions relative to the injection zone(s) and 

the direction of water movement, where known; 

(7) A compilation of available baseline geochemical data on the proposed 

injection zone and nearest adjacent porous and permeable formation to the 

confining zone, existing utilized water supply aquifers and any other USDWs 

designated by the Director. 

(8) Proposed operating data: 

(i) Average and maximum daily injection rate and volume of the carbon dioxide 

stream; 

(ii) Average and maximum surface injection pressure; 

(iii) The source of the carbon dioxide stream; and 

(iv) An analysis of the chemical and physical characteristics of the carbon 

dioxide stream; 

(9) Proposed formation testing program to obtain an analysis of the chemical and 

physical characteristics of the injection zone and confining zone; 

(10) The compatibility of the carbon dioxide stream with fluids in the injection 

zone and minerals in both the injection and the confining zone(s), based on the 

results of the formation testing program or other data, and with the materials 

used to construct the well; 

538
(11) Proposed stimulation program and a determination that stimulation will not 

compromise containment; 

(12) The results of the formation testing program as required in paragraph (j) 

of this section; 

(13) Proposed procedure to outline steps necessary to conduct injection 

operation; 

(14) A well bore schematic of the subsurface construction details and surface 

wellhead construction; 

(15) Injection well construction procedures that meet applicable requirements; 

(16) Proposed area of review and corrective action plan required by §146.25(b) 

(2); 

(17) All available logging and testing program data on the well required by 

§146.25(e)(1); 

(18) The proposed demonstration method for mechanical integrity pursuant to 

§146.25(j)(5); 

(19) A demonstration, satisfactory to the Director, that the applicant has met 

the financial responsibility requirements under §146.25(c); 

(20) Proposed testing and monitoring plan required by §146.25(g); 

(21) Proposed injection and monitor well(s) plugging plan required by §146.25(j) 

(2); 

(22) Proposed post-injection site care and site closure plan required by 

§146.25(k); 

(23) Proposed emergency and remedial response plan required by § 146.25(l); and 

(24) Any other information requested by the Director necessary to ensure 

protection of USDWs. 

539
Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5550 5.11. Comments on the Proposed Well Plugging Requirements (146.92) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28068 

Comment: (j) Injection and monitor well plugging 

(1) Prior to the well plugging, the owner or operator must flush each injection 

well with a buffer fluid, determine bottomhole reservoir pressure, and perform a 

final external mechanical integrity test. 

(2) Well Plugging Plan. The owner or operator of a well must prepare, maintain, 

and comply with a well plugging plan for injection and monitor wells that is 

acceptable to the Director. The requirement to maintain and implement an 

approved plan is directly enforceable regardless of whether the requirement is a 

condition of the permit. The well plugging plan must be submitted as part of 

the permit application and must include the following information: 

(i) For injection wells and any monitor wells that penetrate the injection zone: 

540
(A) Appropriate testing or determination of bottomhole reservoir pressure; 

(B) Appropriate testing or determination of reservoir pressure (including, for 

example, through additional perforations) in other formations only if required 

by the Director; 

(C) Appropriate testing methods to ensure final external mechanical integrity as 

specified in §146.25(f)(5); 

(D) The type and number of plugs to be used; 

(E) The placement of each plug including the elevation of the top and bottom of 

each plug; 

(F) The type and grade and quantity of material to be used in plugging. The 

material must be suitable for use with the carbon dioxide stream, reservoir and 

fluid conditions; and 

(G) The method of placement of the plugs. 

(ii) For monitor wells that do not penetrate the injection zone, information to 

demonstrate that the wells will be plugged in compliance with applicable state 

requirements. 

(3) Notice of intent to plug. The owner or operator must notify the Director at 

least 60 days before plugging of a well. At this time, if any changes have been 

made to the original well plugging plan, the owner or operator must also provide 

the revised well plugging plan. At the discretion of the Director, a shorter 

notice period may be allowed. 

(4) Plugging report. Within 60 days after plugging the owner or operator must 

submit a plugging report to the Director. The report must be certified as 

accurate by the owner or operator and by the person who performed the plugging 

operation (if other than the owner or operator.) 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

541
Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28254 

Comment: Pages 43518 to 43520- Proposed Well Plugging, Post- Injection Site Care, and 

Site Closure Requirements 

The well sealing requirements should meet the state standards, if more stringent 

than the federal standards. For New Jersey, the entire confining layer and fresh 

water aquifer zones should properly sealed with a grout that meets the state and 

EPA standards. The permeability tests on the grout should be done using the CO2 

stream that was injected into the well. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27923 

Comment: 146.92 Well plugging 

The proposed rules describe plugs as a way to abandon Class VI wells. Class VI 

wells should be properly abandoned to prevent a health or environmental hazard 

by completely filling them from the bottom up to the land surface with an 

542
approved sealant (e.g., cement) to ensure these wells do not become a health 

hazard or environmental concern. This assumes the well was properly constructed 

in the first place and not grandfathered in as is proposed. We suggest that if a 

well is found that is not properly constructed then another form of plugging may 

be necessary to protect the groundwater resource. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5600 5.12. Comments on the Proposed Post-Injection Site Care Requirements 

(146.93) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28051 

Comment: EPA did not raise the issue of its proposed 50-year default period for postinjection site care in the NODA. However, API encourages EPA to reconsider this 

extreme time frame, as there does not seem to be a scientific basis for the 

selected period of 50 years. Establishing a fixed and unusually long time 

period, even with the Director discretion provided, may create a significant 

barrier for operators considering entry into GS operations. Criteria for 

543
determining the period for post- injection site care should be performance-based 

and a function of the site specific characteristics of a project such as project 

size, geologic factors, and relative risk of the project. Clear guidelines also 

need to be established regarding when operators have met the performance 

standards that determine site closure. Specifically, the standard that the 

project no longer poses an endangerment to USDWs needs to be defined using 

reasonable risk-based criteria. Consideration should also be given as to the 

mechanism for transfer of long-term liability to the appropriate government 

entity; what entity will be responsible for the long-term liability and what 

type of stewardship is required. Please refer back to API's comments submitted 

in Dec., 2008 for specific suggested changes on site closure criteria and 

requirements. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28069 

Comment: (k) Post-injection site care and site closure 

(1) The owner or operator of a well must prepare, maintain, and comply with a 

plan for post-injection site care and site closure that meets the requirements 

of paragraph (1)(ii) of this section and is acceptable to the Director. 

(i) The owner or operator must submit the post-injection site care and site 

closure plan as a part of the permit application to be approved by the Director. 

(ii) The post-injection site care and site closure plan must include the 

following information: 

544
(A) The projected pressure differential between pre-injection and projected 

post-injection pressures in the injection zone; 

(B) The projected position of the carbon dioxide plume and associated pressure 

front at site closure as demonstrated in the area of review evaluation required 

under §146.25(b)(1), (3) and (5); 

(C) A description of post-injection monitoring location, methods, and proposed 

frequency; and 

(D) A proposed schedule for submitting post-injection site care monitoring 

results to the Director. 

(iii) Upon cessation of injection, owners or operators of wells must either 

submit an amended post-injection site care and site closure plan or demonstrate 

to the Director through monitoring data and modeling results that no amendment 

to the plan is needed. 

(iv) The owner or operator may modify and resubmit the post-injection site care 

and site closure plan for the Director’s approval within 30 days of such change 

(2) The owner or operator shall perform monitoring following the cessation of 

injection as follows: 

(i) The owner or operator shall continue to conduct monitoring as specified in 

the Director-approved post-injection site care and site closure plan, pursuant 

to the performance based criteria described in §146.25(k)(2)(iii). 

(ii) The owner or operator may request and demonstrate to the satisfaction of 

the Director that the post-injection site care and site closure plan should be 

revised to reduce the frequency of monitoring. 

(iii) Prior to authorization for site closure, the owner or operator must 

demonstrate to the Director, based on monitoring, other site-specific data, and 

modeling that is reasonably consistent with site performance that no additional 

monitoring is needed to assure that the geologic sequestration project does not 

pose an endangerment to USDWs. The owner or operator must demonstrate, based on 

the current understanding of the site, including monitoring data and/or 

modeling, all of the following: (A) the estimated magnitude and extent of the 

project footprint (carbon dioxide plume and the area of elevated pressure) ; (B) 

the estimated location of the detectable carbon dioxide plume ; (C) that there 

545
is no significant leakage of either carbon dioxide or displaced formation fluids 

that is endangering USDWs; (D) that the injected or displaced fluids are not 

expected to migrate in the future in a manner that encounters a potential 

leakage pathway into an USDW; (E) that the injection wells at the site completed 

into or through the injection zone or confining zone are plugged and abandoned 

in accordance with these requirements; and (F) any remaining project monitoring 

wells at the site are being used and managed pursuant to a plan approved by the 

Director in accordance with §146.25(k)(4). 

(3) Notice of intent for site closure. The owner or operator must notify the 

Director at least 120 days before site closure. At this time, if any changes 

have been made to the original post-injection site care and site closure plan, 

the owner or operator must also provide the revised plan. At the discretion of 

the Director, a shorter notice period may be allowed. 

(4) After the Director has authorized site closure, the owner or operator must 

plug all monitoring wells in a manner which will not allow movement of injection 

or formation fluids that endangers an USDW except that designated wells may 

remain unplugged pursuant to §146.25(k) (2)(iii)(F) with the consent of the 

owner and operator and pursuant to a post-closure monitoring and plugging plan 

approved by the Director which shall provide for, and designate the person 

responsible for, operating and plugging all such monitoring wells in a manner 

which will not allow movement of injection or formation fluids that endangers an 

USDW. 

(5) Once the Director has authorized site closure, the owner or operator must 

submit a site closure report within 90 days after completion of all closure 

operations. The report must include: 

(i) Documentation of appropriate injection and monitoring well plugging as 

specified in §146.25(j) and paragraph (4) of this section. The owner or operator 

must provide a copy of a survey plat which has been submitted to the local 

zoning authority designated by the Director. The plat must indicate the location 

of the injection well(s) relative to permanently surveyed benchmarks. The owner 

or operator must also submit a copy of the plat to the Regional Administrator of 

the appropriate EPA Regional Office; 

(ii) Documentation of appropriate notification and information to such State, 

local and tribal authorities as have authority over drilling activities to 

enable such State and local authorities to impose appropriate conditions on 

subsequent drilling activities that may penetrate the injection and confining 

546
zone(s); and 

(iii) The volume of fluid injected, the injection zone or zones into which it 

was injected, and the period over which injection occurred. 

(6) Each owner or operator of a injection well must provide notification to the 

designated state authority of the following information: 

(i) The fact that land has been used to sequester carbon dioxide; 

(ii) The name of the State agency, local authority, and/or tribe with which the 

survey plat was filed, as well as the address of the Regional Environmental 

Protection Agency Office to which it was submitted; and 

(iii) The volume of fluid injected, the injection zone or zones into which it 

was injected, and the period over which injection occurred. 

(7) The owner or operator must retain for three years following site closure, 

records collected during the post-injection site care period. The owner or 

operator must deliver the records to the Director at the conclusion of the 

retention period, and the records must thereafter be retained at a location 

designated by the Director for that purpose. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27924 

Comment: 146.93 Post injection site care and closure 

547
We suggest that post injection site care and closure data be required to be 

posted on-line. This does not address site reclamation beyond re-vegetating the 

pad, which currently is regulated in Oregon. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jim Stovall 

Commenter Organization: 

EPA Letter ID: 0389 

EPA Comment ID: 28306 

Comment: In addition, we recommend that a third party verify data submitted by the 

operator on a proposed Site Closure and Monitoring Plan. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status:

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5650 5.13. Comments on the Proposed Emergency and Remedial Response 

Requirements (146.94) 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

548
Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28070 

Comment: (l) Emergency and Remedial Response Plan 

(1) As part of a permit application or request for revision to operate under 

this section, the owner or operator must provide the Director with an emergency, 

risk-based remedial response plan that describes actions to be taken to address 

movement of the injection or formation fluids that may cause an endangerment to 

an USDW during construction, operation, closure and post-closure periods. 

(2) If the owner or operator obtains evidence that the injected carbon dioxide 

stream, displaced formation fluids or an associated pressure front endangers an 

USDW, the owner or operator must: 

(i) Cease injection in a prudent manner considering circumstances. 

(ii) Take all steps reasonably necessary to identify and characterize the 

endangerment posed; 

(iii) Notify the Director or the designated representative within 24 hours of 

becoming aware of the endangerment; and 

(iv) Implement the emergency and remedial response plan approved by the Director 

and keep the Director apprized of the implementation. 

(3) The Director may allow the operator to resume injection prior to remediation 

if the owner or operator demonstrates that the injection operation will not 

endanger USDWs. 

(4) The owner or operator must notify the Director and obtain his approval prior 

to conducting any well workover or other remediation measures not listed in the 

549
emergency and remedial response plan. 

(5) If an owner or operator obtains evidence that a pressure front associated 

with one geologic sequestration project intersects or will more likely than not 

intersect the pressure front or area of review associated with another project, 

the owner or operator obtaining such evidence must notify the Director. The 

Director shall notify the owner or operator of the other geologic sequestration 

project. If the Director determines that the pressure front associated with one 

project interferes or will more likely than not interfere with the ability of 

another project to comply with the terms of its permit(s), the Director may 

require the owners or operators of the interfering or potentially interfering 

projects to modify operations as necessary to mitigate or avoid such 

interference. Such modifications may also include modifications mutually agreed 

upon by the respective owners and operators and approved by the Director." 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27915 

Comment: Remedial Action 

Triggers should be established for when remedial action is required. The new 

regulations should address this during the permitting process so the operator and 

regulatory agency know what action is expected before impacts are observed. 

Everyone will then understand what the threshold is and will help to prevent legal 

efforts intended to delay the initiation of remedial actions when environmental 

impacts have been observed. 

550
Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 5700 5.14. Comments on Other Aspects of the Proposed Rule 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27865 

Comment: c. At page 47 FR 44805 col. 2, EPA says 

In the preamble of the proposed rule, EPA described an adaptive approach 

to developing regulations for GS. This approach would allow the Agency 

to establish regulations to protect USDWs and enable the Agency to make 

changes to regulations over time as information from demonstration 

projects and other studies becomes available. 

An adaptive approach is a poor idea! Such a system prevents a company 

from finalizing a facility design. The designer is never sure another rule 

modification wouldn’t invalid the current design or require an add on, which is 

not appropriate for the facility as built. We cannot change facility designs at 

the whim of the regulator! 

551
Individual Response: The final rule is based on the most recent GS-related data, information, and 

scientific research available. EPA intends to continue to collect data on GS and to incorporate such 

data as it implements its adaptive approach to GS rulemaking. EPA plans to, every six years, collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary.

For additional information on the adaptive approach and site specific requirements, see the responses 

to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Dwight N. Lockwood 

Commenter Organization: Global Energy, Inc. 

EPA Letter ID: 0332 

EPA Comment ID: 28195 

Comment: 11. The rule should provide for data collection and reporting to facilitate EPA 

knowledge accumulation and its "adaptive" rule management. 

12. We support USDW protection, and argue for a practical rule and 

implementation to facilitate actual deployment of GS (i.e. the process needs to 

be practical or it will not evolve timely). 

Individual Response: The final rule is based on the most recent GS-related data, information, and 

scientific research available. EPA intends to continue to collect data on GS and to incorporate such 

data as it implements its adaptive approach to GS rulemaking. EPA plans to, every six years, collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

For additional information on the adaptive approach and site specific requirements, see the responses 

to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

552
Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27892 

Comment: 

While such specificity allows for a focused approach, if approved, it may allow 

Class II wells to be used for GS of CO2 under the rule. The use of Class II 

wells for GS of CO2 will likely allow carbon credits in one form or another, 

even though the injected CO2 would be used to enhance the extraction of 

additional fossil fuels (oil or natural gas), which when consumed releases CO2, 

impeding rather than mitigating CO2 emissions. 

If the proposed wells are to be a part of a climate mitigation strategy, 

supporting data must be supplied to verify that goal. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28049 

Comment: Need for Additional Research 

The Notice of Data Availability (NODA) references new studies that EPA can use 

to finalize its rule- making for geologic storage of CO2. However, API sees 

nothing in the newly available information that suggests a need to postpone the 

553
development of final rules, as opposed to proceeding with adaptive regulations. 

While there is always room to expand the knowledge base, and research into 

various aspects of CO2 storage should continue, the state of the science is more 

than adequate to proceed with EPA rule promulgation and commercial-scale 

implementation of geologic storage in the United States. The proven success of 

30+ years of CO2 enhanced oil recovery, 70+ years of natural gas storage, and 

150 years of oil and gas production, demonstrates the industry knows how to 

safely and effectively drill wells, inject and store fluids, and monitor for 

containment. 

Individual Response: EPA recognizes that the oil and gas industry has decades of experience 

injecting CO2 for the purpose of EOR. The GS rulemaking builds upon existing experience and 

knowledge about safe injection practices in EOR and other injection industries, with tailored 

requirements that address the unique nature of CO2 injection for GS. 

The remainder of this comment pertains to EPA’s proposed GS rule (73 FR 43492) and is outside the 

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for 

EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kyle Isakower 

Commenter Organization: American Petroleum Institute (API) 

EPA Letter ID: 0350 

EPA Comment ID: 28050 

Comment: API contends that states and tribes should play a leading role in managing GS 

projects going forward. Accordingly, states should be permitted to seek primacy 

for the Class VI program, even in the absence of primacy for other well classes 

(partial primacy). Numerous states have decades of experience in regulating CO2 

injection through Class II programs, and those states in particular may have 

much to offer in the context of Class VI wells. A critical component of the 

primacy delegation process is for EPA to ensure that States will be adequately 

funded to deal with the increased workload associated with managing the Class VI 

program. Conversely, some states may not have formations with the necessary 

geologic characteristics to allow GS and so may want to pass on obtaining 

554
primacy for this program. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John McManus 

Commenter Organization: American Electric Power (AEP) 

EPA Letter ID: 0353 

EPA Comment ID: 28058 

Comment: MSD participants explained the agreement reached on the proposed language 

describing wells in classification (b)(4) that would establish a "bright line" 

definition distinguishing (1) wells 

that inject CO2 for EOR/EGR and those that inject CO2 for GS in conjunction with 

EOR/EGR from (2) wells that inject CO2 for GS where EOR/EGR activities and any 

hydrocarbon production would be minimal.. The signatories to that letter 

recommended, consistent with EPA’s intent, that wells used for EOR/EGR should 

remain in Class II and that wells used for EOR/EGR with GS - that meet the (b) 

(4) definition - should also remain in Class II and be subject to the current 

requirements for Class II. Signatories to that letter also agreed that the wells 

used for GS in oil and gas reservoirs that do not meet the criteria of (b)(4) 

should be subject to additional requirements. That letter noted an agreement to 

define such wells as wells used "for geologic sequestration in oil and gas 

formations and where the criteria of paragraph (b)(4) are not met." This letter 

and the attached provisions provide specific recommended requirements for GS in 

oil and gas reservoirs when the criteria of paragraph (b)(4) are not met. 

In the Multi-Stakeholder Discussions since March 31, 2009, the signatories to 

this letter have agreed that wells used for GS in oil and gas reservoirs that do 

not meet the criteria of paragraph (b)(4) should be subject to a set of 

additional requirements different from those that would apply under the current 

Class II provisions to wells that inject CO2 for EOR/EGR and GS, due to the 

potential change in the risk profile when EOR/EGR activities cease. This common 

555
view is also reflected in the four letters you received on March 17, 2009 from 

MSD participants. Each of those March 17 letters asks EPA to include this 

approach in its final GS rule. 

The March 31, 2009 MSD letter included a smaller number of signatories than this 

letter because consensus on all of the attached requirements to that letter had 

not been achieved at that time. A broader consensus has now been achieved, 

allowing submission of the attached revised recommendations. 

Recommended Provisions for GS in Oil and Gas Reservoirs 

Specifically, the undersigned recommend that the attached proposed requirements 

be added to Class II through an amendment to add a new section 146.25, as shown. 

Although the MSD process had also considered that these requirements might be 

promulgated as a new Class VII in a new Part 146, Subpart I, the undersigned MSD 

participants have now agreed that the addition to Class II through a new 146.25 

is the better approach provided that EPA adopts the delegation standard for 

primacy explained in this letter. 

The addition of the attached recommended requirements as a new section 146.25 

should be accompanied by the addition of the word "and" at the end of the new 

paragraphs 144.5(b)(4), 144.80(b)(4) and 146.5(b)(4) proposed in the December 23 

MSG letter and by the addition of a new paragraph (5) in subsections 144.5(b), 

144.80(b) and 146.5(b) reading: 

(5) For geologic sequestration in oil and gas formations and where the criteria 

of paragraph (b)(4) are not met. 

And-consistent with the further recommendations presented by MSD participants on 

May 14, 2009-subsections 144.5(f), 144.80(f) and 146.5(f) should be revised to 

read as follows: 

"(f) Class VI. Wells used for geologic sequestration but not including those 

wells used for geologic sequestration that are regulated under another Class. 

Wells used for geologic sequestration in basalts, coal seams, salt caverns or 

shales are regulated under Class V as experimental wells until such time as the 

Administrator establishes separate requirements by rule for the specific type of 

formation or determines, following public notice and opportunity for comment, 

that wells used for geologic sequestration of carbon dioxide streams into the 

specific type of formation should be regulated under another class." 

556
Under this approach, wells used "[f]or geologic sequestration in oil and gas 

formations and where the criteria of paragraph (b)(4) are not met" would be 

"wells used for geologic sequestration that are regulated under another 

Class"-namely Class II. In conjunction with these revisions and the 

implementation of these requirements, the undersigned MSD participants have 

agreed that the attached proposed section 146.25 requirements should be subject 

to state primacy approval under the standard of section 1422 of the Safe 

Drinking Water Act (SDWA) rather than the alternative standard of section 1425, 

especially where it will be clear that injection for geologic sequestration in 

an oil and gas reservoir will be done without recovery of oil or natural gas. If 

the criteria of (b)(4) are not satisfied, any production of oil and gas would be 

an incidental function of the GS injection activities subject to our proposed 

requirements, and accordingly such injection would not relate-within the meaning 

of section 1425-to: 

(1) the underground injection of brine or other fluids which are brought to the 

surface in connection with oil or natural gas production or natural gas storage 

operations, or 

(2) any underground injection for the secondary or tertiary recovery of oil or 

natural gas. 

It should be noted that - as does EPA’s proposal for Class VI - the attached 

proposal for section 146.25 requirements relies on the continued applicability 

of other provisions of EPA’s existing UIC regulations, including in particular 

the provisions of 144.51, which impose the requirements for maintenance of 

mechanical integrity (MI) and for reporting losses of MI. Requirements for 

responding to a potential lack of mechanical integrity are imposed under 40 

C.F.R. §144.51(q). Requirements for 24-hour reporting are imposed under 40 

C.F.R. §144.51(l)(6). 

Conclusion 

The undersigned respectfully submit the attached recommendations and request 

that EPA promulgate a new section 146.25 be adopted as the regulatory 

requirements applicable to wells used for geologic sequestration (GS) in oil and 

gas reservoirs that do not meet the provisions of the (b)(4) language 

recommended in the joint letter submitted by participants in the MultiStakeholder Discussion (MSD) group on December 23, 2008. As previously noted in 

the December 23, 2008 letter, the consensus recommendations presented in this 

letter are solely for the purpose of GS regulation under the Safe Drinking Water 

Act to protect USDWs and not for the purpose of addressing verification 

557
requirements for carbon credits. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28226 

Other EPA Comment Codes and Descriptions: 4000 4. Comments on Current State GS Activities 

(seeking comment) 

Comment: ROUNDTABLE SUGGESTIONS 

1. Respect State Primacy on SDWA Permitting. We believe that the Agency should 

be explicit in providing a reasonable process whereby states can obtain primacy 

over regulation of Class VI (CCS) wells. Many states already administer SDWA 

programs and have long experience regulating CO2 injection through Class II EOR 

programs. Further, a number of states are moving ahead with developing their 

own initiatives and regulations to solve other issues associated with CCS -- 

incentives provisions and provisions clarifying the nature of potentially 

affected property rights as two examples. As the Agency itself notes in its 

supplement: 

"The Agency is aware that States are currently in various stages of developing 

statutory frameworks, regulations, workgroups, technical guidance, and 

strategies for addressing CCS and GS. Much of the expertise and infrastructure 

currently exists within State UIC Programs. These programs will form the 

foundation for managing GS wells. Additionally, States can use multiple 

authorities beyond those afforded under the SDWA and UIC regulations including 

surface access and land rights, unitization of fields, pore space ownership, 

mineral rights, worker safety and emergency preparedness, and maximization of 

State oil and gas resource exploitation." 

558
Clearly, in determining state primacy, EPA will have to consider how to handle 

projects that span multiple states. We do not believe that issue to be 

insurmountable. Rules could include, for example, provisions for establishing a 

primary state for permitting purposes, with other affected states provided an 

opportunity for notice and comment. 

Such regulatory clarity is critically important, not only to states, but also 

project proponents, interested in early investment in major CCS projects. 

Individual Response: EPA agrees that states should be allowed to obtain primacy for Class VI wells 

independently of other well classes. EPA believes that allowing independent Class VI primacy may 

encourage states to take responsibility for implementation of Class VI regulations and provide for a 

more comprehensive approach to managing CCS projects by promoting the integration of GS activities 

under SDWA into a broader framework for managing CCS. Furthermore, GS operations involve 

ancillary activities (e.g., pipeline operations, pore space ownership, land use rights, and surface 

access) for which states can call upon other authorities that exist at the state level (but outside UIC 

authority) to provide a more comprehensive CCS management approach. In response to concerns 

about which state or region would oversee the permit for projects where the AoR spans state or tribal

boundaries, EPA clarifies that issuance and oversight of a GS permit, including any associated AoR 

boundary-related coordination, is the responsibility of the primacy agency (State or Tribal) or regional 

DI program in the state where the injection well is located. EPA adds that the GS rule, at §146.82(b), 

requires that the Director notify representatives of all states, tribes, and territories in the AoR to 

inform them of the permit application and offer them an opportunity to be involved in any relevant 

activities, such as development of the required project-specific plans. For additional information on 

primacy, please see the preamble to the final rule and responses to comments on the proposed GS 

rule. 

EPA Team Member: Cadmus--Natalie 

Draft Status: 

Date Uploaded: 14-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28227 

559
Comment: 2. Appropriately Characterize CO2. We strongly urge EPA to be very careful in 

its characterization of CO2 under the UIC program. As has been previously 

noted, a successful climate change control program will necessarily be 

predicated on development of -- and public support for -- CCS. EPA could 

inadvertently, and inappropriately, stigmatize CCS, if it veers into an 

unwarranted categorization of CO2 as a pollutant or a hazardous waste. Such 

suggestions would imply a liability risk that would chill further development of 

both CCS and EOR operations. 

3. Characterize Carefully Risks of the Geologic Sequestration of CO2. It is, of 

course, crucial that the final rule meet EPA’s objective of protecting drinking 

water supplies. We remain concerned, however, that some of the more 

prescriptive requirements being proposed for Class VI wells are not supported by 

findings of unique risks actually posed. EPA’s regulations should be based upon 

an accurate characterization of the potential risks posed by the GS of CO2 and 

be specifically tailored accordingly to address those identified risks. This 

will ensure that EPA meets its obligation to provide appropriate protection of 

underground sources of drinking water, while avoiding unnecessary regulations 

that may hamper CCS from going forward or call into question the general safety 

of CO2 storage. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James P. Sims 

Commenter Organization: Western Business Roundtable 

EPA Letter ID: 0357 

EPA Comment ID: 28229 

Comment: 4. Avoid Over-Generalization in Regulations. We strongly urge EPA to avoid 

blanket prohibitions or arbitrary absolutes in the rule. We are concerned by 

the inclusion in the proposed regulations of default provisions that simply 

presume universal application. We believe that approach is problematic. It is 

560
too early to fully understand precisely which methods or technologies will 

ultimately prove optimal. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Pamela F. Faggert 

Commenter Organization: Dominion Resources Services, Inc. 

EPA Letter ID: 0358 

EPA Comment ID: 28233 

Comment: Dominion believes that carbon capture and storage (CCS) is an essential 

component of any future greenhouse gas (GHG) program. We support the development 

of clear, flexible and appropriate regulations that will facilitate investment 

and development of CCS technology while assuring appropriate protections against 

adverse impacts to USDWs. As noted in our comments of December 23, 2008 on the 

initial EPA proposal, likely "targets" for geologic storage in Dominion's 

regulated territory include unmineable coal seams and depleted coal bed methane 

wells. Although they represent only a small fraction of the total U.S. projected 

storage capacity, these targets are the most viable for a significant portion of 

Dominion's CO2 sources. In addition, use of coal seams for GS also would provide 

opportunities for enhanced gas recovery, which could help to make GS projects 

more economically feasible. For these reasons, we encourage a flexible approach 

to regulating the injection and geologic storage of CO2 that provides the 

opportunity for the development and deployment with proper environmental 

safeguards and does not impose unnecessary restrictions or hurdles that could 

hinder such development for certain geologic formations. It is with this 

principle in mind that we offer the following comments. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

561
EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0365 

EPA Comment ID: 28282 

Comment: AWWA and AMWA are extremely concerned about the potential for the construction 

of underground injection wells that simultaneously produce oil and sequester 

carbon dioxide. Currently, oil production is regulated using the Class II 

requirements and geologic sequestration will be regulated using the new Class VI 

requirements. There are significant differences in the permitting and operation 

of these two classes, and companies may try to bypass some of the new Class VI 

requirements by designing and operating the system for several years as a Class 

II project before converting it to geologic sequestration. 

Geologic sequestration and oil production are two completely different 

industrial operations. An enhanced oil recovery (EOR) project should not be 

considered as a simultaneous carbon dioxide sequestration project as well simply 

because a portion of the carbon dioxide injected during the EOR process is not 

recovered. There is a significant amount of effort involved in meeting the 

Class VI well requirements for groundwater monitoring, area of review, 

construction methods and materials, and public notification. The Class VI 

requirements provide for strict protection of underground sources of drinking 

water (USDWs) and these protective measures are completely negated if the 

oil/gas industry is allowed to use the less stringent Class II wells for carbon 

dioxide sequestration. As a result, the potential exists for a significant 

amount of USDW contamination since the Class VI protective measures would not be 

required for Class II wells that simultaneously produce oil and sequester carbon 

dioxide. 

AWWA and AMWA's position is unequivocal: EPA must not develop regulations for 

wells that would simultaneously produce oil and sequester CO2. Geologic sequestration 

technology itself is still being heavily researched and we currently know little about the 

long term impacts of sequestering large amounts CO2. The research community needs 

562
to have a much better understanding of this technology before we expand the ability of 

the energy industry to implement commercial-scale operation of this type of nontraditional geologic sequestration technology. We need a measured approach to the 

implementation of geologic sequestration, not a hurried approach that does not address 

the potential for unintended consequences with unproven technology. 

It is imperative that theoretical and observational research continue and be 

very comprehensive. While the UIC program has a long history, the injection of 

CO2 into the ground is a process that is not well understood. Given its 

buoyancy characteristic, CO2 is much different than other historically injected 

substances and the behavior of the compound under severe pressures and 

temperatures is not well known. We strongly recommend that EPA continue to work 

with DOE to perform theoretical modeling and observational research to gain a 

better understanding of the carbon sequestration process and the effects of CO2 

injection on saline aquifers and the subsurface geology. This information will 

be essential to determining where geologic sequestration should be permitted. 

In summary, given that geologic sequestration technology is still in its 

infancy, we urge EPA to exercise caution and not permit injection wells that 

allow for the simultaneous production of oil and sequestration of carbon dioxide 

at this time. EPA needs to ensure the protection of USDWs and future USDWs from 

harmful unintended consequences. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27910 

Comment: EOR/EGR 

563
We suggest keeping the programs for EOR/EGR and geologic sequestration 

separated. EOR/EGR occurs in areas with oil reservoirs with little contemplation 

to the site's long term storage and CO2 containment characteristics. Long term GS 

CO2 storage should be based upon local site characterization work that verifies 

the reservoir provides the storage requirements with minimal environmental 

risks. 

EPA acknowledges that there are differences between Class II and VI operations 

that warrant different treatment such as risk profiles, formation pressures, CO2 

volumes, more opportunities for mobilization, injection rates and operating 

conditions. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara Priest 

Commenter Organization: Oregon Department of Environmental Quality (DEQ) 

EPA Letter ID: 0366 

EPA Comment ID: 27917 

Comment: Non-CO2 Contaminants 

The proposed standard would allow co-disposal of imported non-C02 waste 

streams and non-CO2 contaminants to be injected with the C02unless the 

contaminants would make the CO2 a hazardous waste. Injected gases may not 

qualify as a hazardous waste under current federal standards. It appears that 

the proposed rules would allow a facility to import waste materials to add to 

the CO2 and be injected as a cheap disposal option and we believe this should not 

be allowed to happen. Oregon administrative rules would prohibit the injection 

non-CO2 contaminants if technology is available for their removal. Current state 

rules also prohibit the use of underground injection for most waste disposal. An 

alternative option would be to allow non-CO2 contaminants only as specifically 

addressed in a facility's permit and a statement that the non-C02 contaminants 

564
must be by-products of the CO2 stream and may not be imported for disposal by 

injection with the CO2. States should be able to adopt rules that are more 

restrictive related to this issue. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28102 

Comment: It is because of these water supply challenges that AMWA again urges EPA to 

reexamine the current classification of a USDW (i.e., an aquifer with a total 

dissolved solids (TDS) concentration of less than 10,000 mg/L). As explained in 

our previous comments, new technologies coupled with future water demands and 

resource limitations enhance the feasibility of using high TDS waters as future 

drinking water supplies. The potential need to use saline aquifers for potable 

supply, particularly in water-stressed areas, should be considered before 

authorizing the sequestration of carbon dioxide at these locations. 

AMWA member utilities continue to be concerned about the potential for 

unintended, negative consequences for drinking water utilities if GS wells are 

placed above, between or below a USDW or a future USDW. As described in the 

NODA, GS is a new and emerging technology and projects in the U.S. are in the 

demonstration and pilot phase. There is very limited information available from 

these project sites, particularly with regard to data about subsurface 

geochemistry or CO2 seepage into groundwater. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

565
EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Quinlan J. Shea, III 

Commenter Organization: Edison Electric Institute (EEI) 

EPA Letter ID: 0384 

EPA Comment ID: 28143 

Comment: Accordingly, states should be able to seek primacy for only Class VI wells 

should they so choose, to ensure that they are given credit and recognition for 

their valuable efforts on GS without also requiring them to assume the burden of 

the entire UIC program for the state. Adequate funding for primacy states, 

given the extraordinarily detailed process that will likely accompany obtaining 

a Class VI permit, must be ensured. 

Individual Response: EPA agrees that states should be allowed to obtain primacy for Class VI wells 

independently of other well classes. EPA believes that allowing independent Class VI primacy may 

encourage states to take responsibility for implementation of Class VI regulations and provide for a 

more comprehensive approach to managing CCS projects by promoting the integration of GS activities 

under SDWA into a broader framework for managing CCS. Furthermore, GS operations involve 

ancillary activities (e.g., pipeline operations, pore space ownership, land use rights, and surface 

access) for which states can call upon other authorities that exist at the state level (but outside UIC 

authority) to provide a more comprehensive CCS management approach. For additional information on 

primacy, please see the preamble to the final rule and responses to comments on the proposed GS 

rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28144 

566
Comment: II. Comments on the GS studies and interim information summarized in the Notice 

A. For CCS to be viable, GS requirements must be flexible and tailored to sitespecific needs 

Under the Proposed Rule, EPA has adopted an approach specifically tailored to 

the unique characteristics of CO2 deepwell injection. While we generally support 

the Agency’s decision not to be overly prescriptive in the development of the GS 

requirements, certain portions of the technical requirements appear to be 

excessive and unreasonable and will result in higher operational costs without 

meaningful benefits. For example, although certain monitoring technologies are 

utilized in various Regional Carbon Sequestration Partnership (RCSP) Pilot 

Projects (described in Section B of the current NODA), such technologies as 

time-lapse 3D seismic may not be appropriate, reasonable, or cost-effective for 

all GS full-scale projects. Further, the RCSP pilot projects are employing and 

evaluating numerous technologies as part of their research. It is not yet clear 

which of these technologies will be of the most value; assuming all of these are 

to be employed for GS projects is misleading. 

In the promulgation of the Final Rule, we encourage EPA to continue to build 

upon the concept of flexibility, reduce the amount of unnecessary and costly 

requirements, and, in certain cases, provide greater discretion to the States in 

deciding the technical specifications applicable to siting, well construction, 

and monitoring. State-level oversight and regulation of well design, 

construction, and operations provides the opportunity for local and sitespecific geologic or geographic issues to be addressed that might otherwise be 

absent or inapplicable to another State or area. 

Individual Response: EPA agrees with the commenter that states should be allowed to obtain 

primacy for Class VI wells independently of other well classes. EPA believes that allowing independent 

Class VI primacy may encourage states to take responsibility for implementation of Class VI 

regulations and provide for a more comprehensive approach to managing CCS projects by promoting 

the integration of GS activities under SDWA into a broader framework for managing CCS. 

Furthermore, GS operations involve ancillary activities (e.g., pipeline operations, pore space 

ownership, land use rights, and surface access) for which states can call upon other authorities that 

exist at the state level (but outside UIC authority) to provide a more comprehensive CCS management 

approach. For additional information on primacy, please see the preamble to the final rule and 

responses to comments on the proposed GS rule. 

567
Other portions of this comment pertain to EPA’s proposed GS rule (73 FR 43492) and are outside the 

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for 

EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Brianne Metzger-Doran 

Commenter Organization: Spectra Energy Corp 

EPA Letter ID: 0385 

EPA Comment ID: 28145 

Other EPA Comment Codes and Descriptions: 2100 2.1 DOE Regional Carbon Sequestration 

Partnership Projects 

Comment: B. Significant work is still ongoing at the pilot stage for GS 

As a member of the Plains CO2 Reduction (PCOR) Partnership and the sponsor of a 

Phase III pilot project, Spectra Energy is actively involved in the development 

of new data from pilot efforts in GS. As EPA notes in the NOPR, 

EPA received comments from stakeholders requesting that additional data 

be made available to the public before a final rulemaking (particularly 

related to specific areas of GS) and indicating that more research is 

needed to support GS in general. Many commenters suggested that 

supplementary research on GS is necessary prior to rule promulgation and 

that EPA should wait until the Department of Energy (DOE)-sponsored 

Phase II and Phase III pilot projects are complete before finalizing the 

GS rule. Others believed that a final rulemaking should proceed and that 

new information and data from ongoing GS research should be considered 

and incorporated over time as part of an adaptive rulemaking process. 

(74 FR 44805) 

In accordance with such, we note that EPA acknowledged that it received many 

comments suggesting that promulgation of this rule should be postponed until the 

DOE-sponsored Phase II and Phase III projects are complete. It is Spectra’s 

understanding that the summaries for Phase II projects are due to the DOE by 

December 31, 2009. The actual data and results from these Phase II projects 

could provide significant value as EPA proceeds with development of this Rule. 

568
As such, given the short timeframe, Spectra recommends that EPA postpone final 

promulgation of the GS Rule until it has reviewed those Phase II reports. 

Individual Response: The Phase II RCSP projects are due to be completed soon and EPA plans to 

monitor those projects and others. However, EPA does not plan on delaying implementation of the rule 

in order to obtain results of these or other studies. EPA is implementing an adaptive approach to the 

rule in order to best incorporate ongoing research while still affording protection to USDWs from 

endangerment on a nationally consistent and early basis. EPA plans, every six years, to collect and 

review data on GS projects to determine whether the appropriate amount and types of information 

and appropriate documentation are being collected, and to determine if modifications to the 

requirements are appropriate or necessary. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 21-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28304 

Comment: V. EPA Should Administer the CCS Program Rather than States. 

In the NODA, EPA stated that "The EPA has honored a commitment to 

working with State co-regulators to address regulatory issues related to GS through 

a series of stakeholder and technical workshops, public hearings, and EPA 

participation with national organizations including the Ground Water Protection 

Council, the Interstate Oil and Gas Compact Commission, and the American 

Association of State Geologists. EPA values coordination with States and State coregulators 

and will continue an open dialogue as the Agency moves forward in the 

regulatory development process." 

Sierra Club wants to reiterate the point that it raised in its previous comments 

that, at least at the early stages, EPA should administer the program with the 

help of a technical advisory board that would ensure the initial implementation 

of a national CCS program will be based on the best science, insulate decisions 

from profit and political motives, facilitate good public perception of CCS and 

would ensure the long-term integrity of the program. The International Risk 

569
Governance Council stressed that "[a]ssignment of regulatory responsibility to 

competent and trustworthy bodies or agencies will be paramount in assuring the 

public that the technology is deployed with adequate oversight and safeguards." 

[FOOTNOTE 8] A nationally administered program will also enable federal 

coordination of information for this young program, ensure information-sharing 

to other states and developing nations, and help manage regional issues that 

transcend state lines. 

[FOOTNOTE 8]: IRGC, Regulation of Carbon Capture and Storage, p. 24, available 

at http://www.irgc.org/IMG/pdf/Policy_Brief_CCS.pdf (last visited December 17, 

2008). 

Finally, federal administration is appropriate because CCS permit decisions 

require evaluation of many complicated technical issues that demand a high level 

of expertise, which state regulatory authorities are not currently equipped to 

handle. In fact, the first state permit issued to a CCS project demonstrates 

that there is cause for concern over the capacity and competency of some state 

regulatory agencies to properly regulate a CCS program. The state of West 

Virginia issued a carbon sequestration permit to American Electric Power for the 

Mountaineer Power Station. This permit has a number of problematic provisions. 

For instance, the permit allows hydraulic fracturing of the rock strata in the 

injection zone. In addition the permit does not contain adequate operating and 

monitoring requirements. The permit is written on the assumption that the agency 

can already predict what will happen, rather than from the standpoint that this 

is an experimental project, and the agency needs to verify all assumptions. 

The success or failure of CCS cannot rest on the decisions of state 

administrators like the ones in Florida responsible for the sewage injection 

debacle. "[A] single major accident, resulting from inadequate regulatory 

oversight, anywhere in the world, could seriously endanger the future viability 

of GS [geologic sequestration]." EPA must take responsibility for administration 

of the nation’s CCS program, at least for the first few years until the task 

becomes less extraordinary. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

570
Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jim Stovall 

Commenter Organization: 

EPA Letter ID: 0389 

EPA Comment ID: 28305 

Comment: We have reviewed Parts I and II of 40 CFR Parts 144 and 146, Federal 

Requirements Under the Underground Injection Control (UIC) Program for Carbon 

Dioxide Geologic Sequestration (GS) Wells; Proposed Rule. We realize that the 

Proposed Rule is promulgated under the Safe Drinking Water Act (SDWA) designed 

to protect Underground Sources of Drinking Water (USDW); however, we also have 

concerns on GS that are clearly outside the scope of the this Proposed Rule. We 

wish to make comments to the Proposed Rule as well as general comments on our 

concerns that are outside the scope of the Proposed Rule. 

Comments on the Rule. 

Our biggest concern is on the issue of "Primacy." The "Director," as defined in 

the Rule, is the person responsible for permitting, implementation, and 

compliance of the UIC program, which, in our case, is the State of New Mexico. 

The Director has discretionary authority on several issues of concern to this 

office which includes: the depth to the target injection zone, whether this zone 

is below, between, or above USDWs; exempting aquifers from being afforded 

protection as a USDW; use of tracers; monitoring of GS sites, whether soil gas 

and surface monitoring should be required and if the GS Monitoring Plan should 

be a Director-approved plan (entirely?); and the discretion to shorten the 

tentative 50-year fixed timeframe for the post-injection site care monitoring 

plan. 

We agree that the above topics are not without merit; however, we propose 

additional wording within the Rule that addresses our concerns. A suggestion is, 

"The director has jurisdiction for UIC wells under the clean water act, but that 

does not confer exclusive jurisdiction over GS activities on federal lands. 

Rather, the GS lessee must obtain both the approval of the Director under the 

clean water act and the BLM under the Mineral Leasing Act. Therefore, the 

Director does not have the exclusive authority to grant approval for an 

operation proposed on the federal mineral estate. Thus, even if the operator has 

571
secured the Director’s approval for an operation, the operator cannot take any 

actions on these leases without the concurrent approval of the BLM." 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jim Stovall 

Commenter Organization: 

EPA Letter ID: 0389 

EPA Comment ID: 28308 

Comment: Conclusion. 

We appreciate the opportunity to make specific comments to the Proposed Rule; 

and to express our general concerns regarding GS. We addressed the topic of 

"Primacy" and made a recommendation on possible additional wording to the 

Proposed Rule. We suggested that a third party verify data regarding a proposed 

Site Closure and Monitoring Plan, and we made general comments outside the scope 

of the Proposed Rule regarding human health, air, ecosystems and illegal dumps. 

Further, we recommended emphasis be placed on the accounting of carbon dioxide. 

We are fortunate to be involved in the possible start up of a new industry. We 

should carefully tread these waters at the beginning to ensure a more viable end 

goal of sequestering carbon dioxide from the atmosphere. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 26-JAN-10 

Notes: 

572
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28313 

Comment: The NODA notes that the availability of data could change EPA's approach to 

final rule-making, and this is the adaptive approach that was discussed briefly 

a moment ago. EEI supports this adaptive approach. We think that it's more 

appropriate than waiting until after the data is gathered in final form to adopt 

the rules. In fact, EEI believes a regulatory framework is needed in the short 

term to spur development of a commercial scale GS industry, and currently 

available information is sufficient to form the basis of an effective and safe 

program. 

Individual Response: The final rule is based on the most recent GS-related data, information, and 

scientific research available. EPA intends to continue to collect data on GS and to incorporate such 

data as it implements its adaptive approach to GS rulemaking. EPA plans to, every six years, collect 

and review data on GS projects to determine whether the appropriate amount and types of 

information and appropriate documentation are being collected, and to determine if modifications to 

the requirements are appropriate or necessary. 

For additional information on the adaptive approach and site specific requirements, see the responses 

to comments on the proposed rule in the rulemaking docket. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Harold Buckley 

Commenter Organization: Edison Electric Institute 

EPA Letter ID: 0540 

EPA Comment ID: 28319 

Comment: avoid hindering progress states have made on this front. The NODA suggests an 

approach that would give the states substantial authority under a delegated 

program through primacy. EEI agrees that states and tribes have decades of 

573
valuable experience in this area and should play a key role in managing carbon 

capture and storage projects. In fact, states also have substantial authority to 

regulate aspects of carbon capture and storage in issues relating to property 

rights and financial incentives beyond injection and storage. However, it is 

important that states be given primacy for Class VI wells only if they request 

it or if they choose to do so. This would allow them to be part of the 

administrative process or to actually run it within their state without being 

required to assume the burden of the entire UIC program for their state. 

And then, finally, it's vitally important that the EPA ensure adequate funding 

for primacy states given the extraordinarily detailed process that will likely 

accompany obtaining a Class VI permit. That concludes my comments and thank you 

very much. 

Individual Response: EPA agrees with the commenter that states should be allowed to obtain 

primacy for Class VI wells independently of other well classes. EPA believes that allowing independent 

Class VI primacy may encourage states to take responsibility for implementation of Class VI 

regulations and provide for a more comprehensive approach to managing CCS projects by promoting 

the integration of GS activities under SDWA into a broader framework for managing CCS. 

Furthermore, GS operations involve ancillary activities (e.g., pipeline operations, pore space 

ownership, land use rights, and surface access) for which states can call upon other authorities that 

exist at the state level (but outside UIC authority) to provide a more comprehensive CCS management 

approach. For additional information on primacy, please see the preamble to the final rule and 

responses to comments on the proposed GS rule. 

Other parts of this comment pertain to EPA’s proposed GS rule (73 FR 43492) and are outside the 

scope of the Notice of Data Availability. Please see responses to comments on the proposed rule for 

EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 01-OCT-10 

Notes: This comment contains text from lines 100 to 115, which is an excerpt from the previous 

section, lines 99 to 106. This comment appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Steve Crookshank 

Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry 

EPA Letter ID: 0541 

EPA Comment ID: 28326 

574
Comment: Lastly, API contends that states and tribes should play a key role in managing 

CCS projects going forward. 

Accordingly, states should be able to gain primacy as long as they show that 

their regulations are at least as stringent as the proposed minimum federal 

requirements. Additionally, states should be permitted to seek primacy for the 

Class VI program even in the absence of primacy for other well classes. The 

geologic variation across the country justifies partial primacy. Numerous states 

have decades of experience regulating CO2 injection to Class II programs, and 

those states in particular have much to offer in the context of Class VI wells. 

A critical component of the primacy delegation process is for EPA to ensure that 

states will be adequately funded to deal with the increased burdens associated 

with managing the Class VI program. Conversely, some states will not have 

formations with the necessary geologic characteristics to allow geologic 

sequestration and so may want to decline on obtaining primacy for this program. 

Individual Response: EPA agrees with the commenter that states should be allowed to obtain 

primacy for Class VI wells independently of other well classes. EPA believes that allowing independent 

Class VI primacy may encourage states to take responsibility for implementation of Class VI 

regulations and provide for a more comprehensive approach to managing CCS projects by promoting 

the integration of GS activities under SDWA into a broader framework for managing CCS. 

Furthermore, GS operations involve ancillary activities (e.g., pipeline operations, pore space 

ownership, land use rights, and surface access) for which states can call upon other authorities that 

exist at the state level (but outside UIC authority) to provide a more comprehensive CCS management 

approach. For additional information on primacy, please see the preamble to the final rule and 

responses to comments on the proposed GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

**************************************************************************************

**************************************************** 

EPA Comment Code: 6000 6. Other Comments that are Out of Scope for the NODA 

EPA Team Member: 

Draft Status: 

Date Uploaded: July 16, 2009 

Notes: 

Comment Summary: 

575
Response to Comment Code: 

Individual Comments

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Anonymous8 

Commenter Organization: 

EPA Letter ID: 0322 

EPA Comment ID: 27856 

Comment: what is being proposed is extremely dangerous for all on earth. what would be 

better is simply cutting out the extreme amounts of carbon we are creating. it 

is clear we need india and china and russia to go along with this. we also need 

the developing nations to be willing to forestall. i think the usa should set an 

example and encourage simplicity. to let those bank execs and oil execs erect 

houses that have 50 rooms and 23 bathrooms is an example of excess. why not tax 

them to death so that they need to live on a simpler plane. that wold also give 

the usa govt money to help those who cant even afford to buy a loaf of bread and 

who are livinin tents in the foreest. what is going on is excess, greed, 

venality, viciousness on the part of those bank execs, oil co execs. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0323 

EPA Comment ID: 27857 

Comment: Oil refiner says CO2 bill to cost it $7 billion a year 

http://www.reuters.com/article/GCA-GreenBusiness/idUSTRE57R4JJ20090828 

We cannot afford Cap & Trade and there is no technical reason for CO2 

sequestration! 

576
Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 23-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Tony Eng 

Commenter Organization: Ecospec USA, Inc. 

EPA Letter ID: 0324 

EPA Comment ID: 27858 

Comment: CO2 geologic sequestration is still not the best solution as end results need 

time to verify. There are few other available technologies within and outside 

US. Of which, Ecospec CSNOx methodology (www.ecospec.com) by treating the CO2 

emission using activated water is more feasible. Cost of CO2 low-energy 

breakdown is also very attractive as compared with CO2 GS method. With estimated 

costing over US$150 per ton of CO2, it may generate more carbon footprint while 

during sequestration and transportation. CSNOx is one of few new methods 

developed by R&D outfits that deserve more support and attention; whcih is 

happening in Europe and Asia. The company welcome participation from 

gonvernmental and private insitutions for implementation. Currently working with 

various installation in Europe and Aisa, this technology and few other similar 

post combustion CO2 emission reduction technologies position itself as better 

alternative against heavy scaled CO2 GS methodology. There should be a clear 

advantage by simply breaking down the tough CO2 with very low energy source 

instead of commencing heavy CO2 GS process. CSNOx technology manage to remove 

every 100 kg of CO2 using merely 3 kWhr of energy, excluding water plumbing 

power. Already with firm schedule of installing CSNOx system onboard of Aframax 

class marine oil tanker after impressive onshore and onboard testings. One of 

Asia power plant is also schedule to implement before end of 2009. EPA should 

strongly consider this alternative before pursuing CO2 GS. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

577
Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0325 

EPA Comment ID: 27859 

Comment: I request these attachments beassociated with Dr. Holliday comment submited 7 Sept. 

2009. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27860 

Comment: 1. EPA relies on a faulty basis for needing Class VI injection wells rules. 

EPA has been very careful to avoid saying climate change is caused by greenhouse 

gases. They have consistently cited the IPCC as saying "as CO2 increases, the 

climate temperature increases." However, when a person reads EPA documents 

concerning Class VI injection wells and greenhouse gases, it becomes clear there 

would be no Class VI well rule proposal, if EPA did not believe climate change 

is caused by anthropogenic greenhouse gases.. In this regard, the Technical 

Support Document for Endangerment and Cause or Contribute Findings for 

Greenhouse Gasses under Section 202(a) of the Clean Air Act (TSD) ( 

http://www.epa.gov/climatechange/endangerment/downloads/TSD_Endangerment.pdf), 

EPA almost exclusively cites Intergovernmental Panel on Climate Change (IPCC) 

documents. The IPCC is a governmental body almost devoid of technically trained 

participants. IPCC is politically driven (Note that some of the IPCC critics in 

578
this video are/were part of the IPCC team 

http://youtube.com/watch?v=xzSzItt6h-s) 

There is no way a reasonable person reading the EPA report cannot recognize the 

care with which EPA selects their reference to avoid peer reviewed technology. ( 

http://www.carlineconomics.com/files/pdf/end_comments_7b1.pdf). Experts in the 

field Dr. Richard Lindzen, Dr. Stephen Schwartz Dr. Roy Spencer, Dr. John 

Christy, & Dr. S. Fred Singer are purposely excluded to avoid appearance of 

relying on science to demonstrate climate temperature increase is not the result 

of anthropogenic greenhouse gases (GHG). 

(http://www.hillsdale.edu/news/imprimis/archive/issue.asp?year=2007&month=08 

http://wattsupwiththat.files.wordpress.com/2009/08/rutanagwdataanalysis.pdf) 

EPA misrepresents the facts when they use IPCC reports as representing what will 

happen to the earth’s climate with time are seeking CO2 sequestration rule, when 

the factual data demonstrates EPA is disillusioning themselves or telling a 

falsehood! 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: G.H. Holliday 

Commenter Organization: Holliday Environmental Services, Inc. 

EPA Letter ID: 0326 

EPA Comment ID: 27926 

Comment: The instant comments, the comments submitted for the Proposed Class VI well rule 

and the comments regarding the Greenhouse Endangerment proposed rule clearly 

demonstrated: 

i. EPA uses out dated and discredited IPCC reports to demonstrate the need 

for controlling greenhouse gases, Carlin (2009). 

ii. EPA has purposefully avoided using or referencing to current factual 

climatological measurements of climate temperature ( 

579
http://www.climatescience.gov/Library/sap/sap1-1/finalreport/default.htm) and ( 

http://www.hillsdale.edu/news/imprimis/archive/issue.asp?year=2007&month=08). 

iii. EPA has purposely misrepresented climate change since year 2000 by 

saying the temperature has increased, when in fact the climate temperature has 

decreased consistent. 

iv. EPA uses measured surfained the unsupportable position that if climate 

temperatures increases and the atmospheric CO2 concentration increases, it is 

proof positive that greenhouse gases are cause for the temperature rise. EPA is 

blind to the fact the earth was recovering from the Little Ice from 1850 to the 

present.(http://www.nipccreport.org). ce temperatures taken from knowingly 

improperly placed thermometer being grossly affected by air conditioning fan 

exhaust, parking lot asphalt and other heat sources. Watts, A. (Is the U.S. 

Surface Temperature Record Reliable?) Heartland Institute, 2009. 

v. EPA has maintained the unsupportable position that if climate 

temperatures increases and the atmospheric CO2 concentration increases, it is 

proof positive that greenhouse gases are cause for the temperature rise. EPA is 

blind to the fact the earth was recovering from the Little Ice from 1850 to the 

present.(http://www.nipccreport.org). 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeffrey A. Miller 

Commenter Organization: 

EPA Letter ID: 0331 

EPA Comment ID: 27932 

Comment: The estimated cost is nearly $1 Trillion annually to achieve Kyoto Protocol 

emission reductions. The projected global temperature increase is 0.44o C from 

2008 to 2030 if nothing is done. The projected global temperature increase is 

0.29o C if CO2 is geologically sequestered. The cost for the US alone is $6.67 

Trillion per degree C. Furthermore, the Executive and Legislative Branches 

efforts to deal with global warming by waving their arms and hoping black box 

solutions become available could, and will highly likely do more damage 

580
discouraging young Americans from selecting a career in the sciences and 

Engineering since they will soon become disillusioned with science and 

engineering’s inability to solve this problem. Ex nihilo, or creating something 

from nothing, as this administration and its legislative allies are doing could 

do irreparable harm to America’s creative abilities to solve tough technical 

problems. 

This postulated problem is based on temperature records from sensors 

inappropriately placed and not in conformance with NOAA standards [FOOTNOTE 2], 

misrepresentation of basis equilibrium chemistry as far as the ice record is 

concerned, and models and results when it is difficult to predict tomorrow’s 

weather; let alone temperatures 20 years out. 

It is therefore suggested to drop all illusions of managing CO2 either using the 

Clean Air Act or new legislation using geologic carbon sequestration as the 

featured technology until it can be proven that global warming is indeed an 

apocalyptic event and/or other more reasonable technologies become available. 

Indeed, there are other legal hurdles to address before carbon capture and 

sequestration can even be considered a viable alternative. As an example, 

exceeding the fracture gradient would more than likely cause a vertical fracture 

that could cause a catastrophic release of CO2 to the environment. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: James J. Dooley 

Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National 

Laboratory 

EPA Letter ID: 0334 

EPA Comment ID: 28207 

Comment: Climate change will affect USDWs even if CCS is not available as an emissions 

reduction technology. While it is obviously a requirement that the USEPA examine 

potential impacts associated with CCS on USDWs, the reader is left with the 

581
strong impression that CCS represents the only (or the principal) danger to 

USDWs associated with climate change mitigation. This is not the case. The 

IPCC’s 2008 Climate Change and Water {FOOTNOTE 4} notes that the large scale 

deployment of geothermal energy, biomass energy, and the continued increased 

reliance on unconventional oil resources all represent potential pathways for 

contaminating underground (as well as surface) sources of potable water. This 

same IPCC report also notes that there is evidence that doing nothing to address 

climate change can also lead to a degradation of ground water through slower 

recharge rates and increased salinity. In presenting the potential dangers 

associated with large scale CCS deployment, the USEPA must do a better job of 

contextualizing these findings and must not leave the reader with the impression 

that not using CCS will result in no harm to USDWs. 

{FOOTNOTE 4} Intergovernmental Panel on Climate Change. Technical Paper on 

Climate Change and Water. Bates, B.C., Z.W. Kundzewicz, S. Wu and J.P. 

Palutikof, Eds. IPCC Secretariat, Geneva, 210 pp. June 2008. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Anonymous9 

Commenter Organization: 

EPA Letter ID: 0335 

EPA Comment ID: 28213 

Comment: CCS is a bad idea to start with and is a waste of resources that should be 

invested in renewables and efficiency instead. But to allow injection above the 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

582
Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Anonymous9 

Commenter Organization: 

EPA Letter ID: 0335 

EPA Comment ID: 28216 

Comment: safe they think it is? It is high time the costs associated with coal-fired 

electricity stopped being subsidized with taxpayer dollars!! 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 04-OCT-10 

Notes: This comment contains text from lines 25 to 26, which is an excerpt from the previous section, 

lines 23 to 26. This comment appears twice in this report, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: I.M. Speakings 

Commenter Organization: 

EPA Letter ID: 0336 

EPA Comment ID: 28217 

Comment: Comment: 

The injection of carbon dioxide into underground reservoirs threathens to 

undermine the geological structure of the reservoir by disolving the limestone 

that defines the boundaries of the reservoir. The potential for cave-in of the 

overlying rock formations is a real possibility. This process will be speeded up 

because of the increase in concentration of carbon dioxide. Over and extended 

period of time the injection of carbon dioxide underground may sufficiently 

weaken the overlying rocks so that the ground will be caving in under our 

civilization. 

583
Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: I.M. Speakings 

Commenter Organization: 

EPA Letter ID: 0336 

EPA Comment ID: 28218 

Comment: A better solution to underground sequestration would be to find usseful purposes 

for the carbon emissions. These carbon dioxide emissions could be used to 

stimulate the growh of crops, and could also be used for industial applications. 

Your favorite carbonated soft dink company could also make your favorite 

carbonated soft drink from the carbon dioxide emissions that have been captured. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 28283 

Comment: the Safe Drinking Water Act (SDWA), 42 U.S.C. Â§ 300f et seq. CURC and its 

members have been at the forefront of promoting the demonstration and commercial 

deployment of carbon capture and storage (CCS) technologies. The widespread 

implementation of CCS will allow the nation to continue to enjoy the economic 

and energy security benefits of using our vast domestic and essential U.S. coal 

584
resources while promoting reduction of greenhouse gas emissions. The American 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Shannon Angielski 

Commenter Organization: Coal Utilization Research Council (CURC) 

EPA Letter ID: 0338 

EPA Comment ID: 28287 

Comment: The potential utility of CCS technology in addressing global climate change is 

the basis for a global effort to demonstrate currently available technologies at 

commercial scale, while still conducting research and development to improve the 

technologies to make them more effective and affordable. EPA is faced with the 

challenge of ensuring that CO2 storage projects do not cause environmental 

damage to USDW, while not stifling the technology with unreasonably conservative 

regulation. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 29-SEP-10 

Notes: This comment is an excerpt of comment 28285 (lines 65-98) above. This comment appears 

twice in this letter, once for each set of line numbers. 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John Borkovich 

Commenter Organization: California State Water Resources Control Board (SWRCB) 

EPA Letter ID: 0339 

EPA Comment ID: 28396 

585
Comment: Example: 

In 1986, a tremendous explosion of CO2 from the lake Nyos, West of Cameroon, 

killed more than 1700 people and livestock up to 25 km away. The dissolved CO2 

is seeping from springs beneath the lake and is trapped in deep water by the 

high hydrostatic pressure. If the CO2 saturation level is reached, bubbles 

appear and draw a rich mixture of gas and water up. An avalanche process is 

triggered which results in an explosive over-turn of the whole lake. 

CO2 injection (to save earth from an uncertain climate changes) may result in 

water supply contamination (EPA declared CO2 as a pollutant that need to be 

regulated) or even catastrophic release that can kill thousands. 

After 20 years of investigation and billions dollars spent at Yucca Mountain 

repository, the US EPA and some scientists cannot warrant that that Yucca Mt 

repository is totally safe. After thousands of years radioactive elements may 

leak from the repository and in another thousands of years may reach drinking 

ground water at concentration exceeding maximum contaminant level. The reported 

CO2 modeling by LBNL cited in this document is limited to 100-years period. 

What fraction of CO2 generated world-wide (30 billion tons/year) can be injected 

into selected formations in the USA and at what cost? How this fraction of 

stored CO2 will affect earth atmosphere and subsequently temperature on earth? 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Emily Rochon 

Commenter Organization: Greenpeace International 

EPA Letter ID: 0342 

EPA Comment ID: 28027 

Comment: CO2 storage is an unproven end-of-pipe 'fix' for climate change emissions 

The EPA is currently considering permitting the burying of CO2 in underground 

586
formations because of a proposed technological solution to the climate problem 

posed by fossil fuel combustion. This solution, known as carbon capture and 

storage (CCS), aims to allow the continued reliance on fossil fuels as a primary 

source of energy while affording a chance to combat climate change. However, in 

almost every way this technology is unproven, risky and expensive. 

Greenpeace does not support CCS as a means to combat climate change. This is due 

to the substantial risks and uncertainties surrounding the effectiveness, 

safety, energy penalties, liability and environmental impacts of CCS and CO2 

storage. In seeking to reduce global warming pollution, Greenpeace believes 

that the US should focus its resources on solutions that avoid the creation of 

CO2 and other greenhouse gases instead of banking on unproven end-of-pipe fixes 

that may create more problems than they solve.[Footnote 1] 

[Footnote 1]:For more information on Greenpeace's position on CCS and CO2 

storage, please read False Hope: why carbon capture and storage won't save the 

climate. Published May 2008. Available at: www.greenpeace.org/ccs. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: John M. McManus 

Commenter Organization: American Electric Power Service Corporation (AEP) 

EPA Letter ID: 0345 

EPA Comment ID: 27878 

Comment: AEP recognizes that the development of a viable carbon capture and sequestration 

("CCS") regulatory program has been cited by many as a prerequisite to the 

implementation of energy reform initiatives involving carbon reduction measures 

on both the federal and state level. EPA predicts that the electric power 

sector, including AEP, "will most likely be the largest potential market for 

[CCS] technologies," and predicts that CCS technology could lead to CO2 

reductions of approximately 80-90% at a single plant. 73 Fed. Reg. 44354, 44492 

(July 30, 2008). AEP believes that our decades of research, engineering 

587
experience, and involvement with the management of fossil fuel combustion 

materials and more importantly, our work with the development and application of 

CO2capture and storage technologies at our Mountaineer PVF, provide us with a 

valuable knowledge base and perspective from which to provide meaningful input 

on the development of EPA's UIC regulations for C02 GS. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara A. Walz 

Commenter Organization: Tri-State Generation and Transmission Association, Inc. (Tri-State) 

EPA Letter ID: 0346 

EPA Comment ID: 27886 

Comment: Tri-State recognizes that the development of a viable carbon capture and 

sequestration (CCS) regulatory program has been cited by many as a prerequisite 

to the implementation of energy reform initiatives involving carbon reduction 

measures. Indeed, earlier this week United States Secretary of Energy Stephen Chu 

wrote to an international audience that coal accounts for 25 percent of the world's energy supply and 

40 percent of 

carbon emissions, and is likely to be a major and growing source of electricity 

generation for the foreseeable future. 

For this reason. I believe that we must make it our goal to advance carbon 

capture and storage technology to the point where widespread. affordable 

deployment can begin in 8 to 10 years. (emphasis original) 

The Secretary of Energy's October 12 letter goes on to itemize the several 

billion dollars that the U.S. Department of Energy is currently investing in CCS 

technologies and demonstration projects. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

588
EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Barbara A. Walz 

Commenter Organization: Tri-State Generation and Transmission Association, Inc. (Tri-State) 

EPA Letter ID: 0346 

EPA Comment ID: 27887 

Comment: EPA predicts that the electric power sector "will most likely be the largest 

potential market for [CCS] technologies," and predicts that CCS technology could 

lead to C02 reductions of approximately 80-90% at a single plant [73 Fed. Reg. 

44354, 44492 (July 30, 2008)]. TriState believes that decades of involvement 

with the management of fossil fuel combustion materials provides our 

organization with a valuable knowledge base and perspective from which to 

provide meaningful input on the development of EPA's VIC regulations for CO2 GS. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27893 

Comment: Assessment of the Proposed Rule The proposed rule repeatedly references climate 

change mitigation by the injection of CO2 as the justification for the need for 

the new class of injection well: 

Summary: "EPA is proposing Federal requirements under the Safe Drinking Water 

589
Act (SDWA) for underground injection of carbon dioxide (CO2) for the purpose of 

geologic sequestration (GS). GS is one of a portfolio of options that could be 

deployed to reduce CO2 emissions to the atmosphere and help to mitigate climate 

change." 

And "If finalized, this proposal would help ensure consistency in permitting 

underground injection of CO2 at GS operations across the U.S. and provide 

requirements to prevent endangerment of USDWs in anticipation of the eventual 

use of GS to reduce CO2 emissions." 

In Part II "What is the EPA Proposing" the proposition reiterates: 

"In addition to protecting USDWs, today's proposed rule provides a regulatory 

framework to promote consistent approaches to permitting GS projects across the 

U.S. and supports the development of a key climate change mitigation 

technology." 

Under Part II A. "Why Is EPA Proposing To Develop New Regulations To Address GS 

of CO2?" Part II. Section 2, states: The Intergovernmental Panel on Climate 

Change (IPCC) has concluded that much of the warming in recent decades is very 

likely the result of human activities (IPCC, 2007). The burning of fossil fuels 

(e.g., from coal fired electric plants and other sources in the electricity and 

industrial sectors) is a major contributor to human induced greenhouse gas 

emissions. 

Fossil fuels are expected to remain the mainstay of energy production well into 

the 21st century, and increased concentrations of CO2 are expected unless energy 

producers reduce the CO2 emissions to the atmosphere. The capture and storage of 

CO2 would enable the continued use of coal in a manner that greatly reduces the 

associated CO2 emissions while other safe and affordable alternative energy 

sources are developed in the coming decades. Given the United States' abundant 

coal resources and reliance on coal for power generation, CCS could be a key 

mitigation technology for achieving domestic emissions reductions" 

And: 

"Congressional climate change legislative proposals (the McCain-Lieberman bill 

S. 280, the Bingaman-Specter bill S. 1766, and the Lieberman-Warner bill S. 

2191) indicate that CCS has the potential to play a significant role in climate 

change mitigation scenarios." 

590
And: 

"Today's proposal provides a regulatory framework to protect USDWs as this key 

climate mitigation technology is developed and deployed." 

The allusion of mitigating climate change or reducing CO2 emissions by geologic 

sequestration cannot be fairly used as persuasive point for this rule without 

providing data demonstrating the mass balance of energy and carbon dioxide in 

the whole system. A great deal of analysis has been completed and posted on the 

docket of cost and incremental cost within the proposed rule for CCS and GS 

implementation but no analysis is made in terms of the actual amount carbon 

dioxide that will be sequestered in relation to the amount of carbon dioxide 

emitted throughout the process (Cost: EPA-HQ-OW-2008-0390-0073 and EPA-HQOW-2008-0390-0094). 

A mass balance of the participating fossil energy processes, generating the CO2, 

must be evaluated to determine if any real reduction in CO2 can be made. CO2 is 

emitted during the excavation and transport of the fossil fuel to a power plant. 

Additional power will be required, and will emit additional CO2, to provide the 

energy to extract the CO2 from the emission stream, to compress, transport, and 

to inject the CO2 into a geologic formation. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27894 

Comment: Very little data is available to evaluate the energy balance of various carbon 

capture processes. The evaluations available limit the efficiency of carbon 

capture (CC) to a percent recovered from the feed stack to the emission stack. 

591
Capturing the carbon is very energy intensive and may increase energy demand by 

up to 50%. (www.lowtechmagazine.com accessed October 27 2008). 

According to Greenpeace International: False Hope: Why carbon capture and 

storage won't save the climate, "capturing and storing carbon uses lots of 

energy; anywhere from 10-40% of a power station's capacity. An energy penalty of 

just 20% would require the construction of an extra power station for every four 

built. These reductions in efficiency will require more coal to be mined, 

transported, and burned, for a power station to produce the same amount of 

energy as it did without CCS." 

The attached summary of a study by Wuppertal Institute, the German Aerospace 

Center (DLR), Zentrum fur Sonnenenergie- und Wasserstoff-Forschung BadenWurttemberg (ZSW) and the Potsdam Institute for Climate Impact Research (PIK) 

for the German government (the full report available at: www.wupperinst.org, 

accessed on line Dec. 23 2008) offers an in depth study of CCS that evaluates 

the various power plant designs, transport, and storage costs; accesses life 

cycle, ecological criteria, carbon neutrality etc. Estimates in the study show a 

20 to 40% increase in energy consumption and the process will only lower 

emissions of CO2, ignoring the increases of other greenhouse gases (GHG). [SEE P. 6 OF 

EPA-OW-2008-0390-0347.PDF FOR THIS DOCUMENT.] 

Consuming an additional 20 to 50% more coal to energize the capture of CO2 is a 

questionable tactic that must supported by transparent data analysis. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27895 

592
Comment: Even as this proposed rule is being considered, the EPA is soliciting 

"applications to conduct research to support the development of sound risk 

management strategies for the underground injection of anthropogenic carbon 

dioxide (CO2)" (accessed online October 6 2008 

http://es.epa.gov/ncer/rfa/2008/2008_star_gsc02.html). The technology for GS of 

CO2 is not yet available or known to be safe. 

Social Justice: The United Nations Environmental Progamme states: "Globally 

around $300 billion or 0.7 per cent of global GDP is being spent on energy 

subsidies annually. The lion's share is being used to artificially lower or 

reduce the real price of fuels like oil, coal and gas or electricity generated 

from such fossil fuels. Cancelling these subsidies might reduce greenhouse gas 

emissions by as much as six per cent a year while contributing 0.1 per cent to 

global GDP." 

Mr. Steiner added: "Whereas fossil fuel subsidies are an example of a blunt 

policy instrument, perpetuating old and inefficient economic models, the CDM is 

an example of a more intelligent, market-based mechanism that is fostering the 

transition to a modern Green Economy". (Accessed online Nov. 14, 2008 

http://www.unep.org/Documents.Multilingual/Default.asp?DocumentID=543&ArticleID= 

5902 ) 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27896 

Comment: Recommendations: 

· A thorough mass balance of the CO2 generated in the participating fossil 

energy processes, generating CO2 must be demonstrated to prove the feasibility 

593
of the proposal; including mining and transport of the fossil fuel to power 

plants, extraction and compression of the CO2 emissions, transport, and 

injection the CO2 into a geologic formation. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27897 

Comment: · If carbon credits are developed, they must not apply to other UIC wells except 

specific Class V experimental wells. To use sequestered carbon dioxide under the 

auspices of this rule, to enhance the recovery of additional fossil fuels is 

imprudent and illogical. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27899 

594
Comment: · Fond du Lac will defer to the experts in the case of pipeline and well 

integrity and the long term safety of geologic sequestration of carbon dioxide. 

However, the skill of deep drilling brings to mind the mudflow disaster of 

Sidoarjo Porong, East-Java Indonesia, which began in May 2006 and is still 

flowing to this day. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27901 

Comment: Although the effort made to address the serious issues of climate mitigation 

through CCS is greatly appreciated, the effort largely appears to mitigate CO2 

emissions via a complex system that will, in reality, increase fossil energy 

consumption. With projected consumption to increase more than 30% by 2030 and 

CCS adding at least 20% additional demand, one may wonder if this proposal 

equates to yet another subsidy for fossil fuel industry. 

The absence of analysis of the carbon neutrality of this project is a serious 

omission. An analysis of this kind should have been the first step in evaluating 

this proposal, yet it is not addressed in the rule or in any of the supporting 

documentation. An endeavor of this magnitude should be demonstrably carbon 

neutral and hopefully operate as a true carbon sink. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

595
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27902 

Comment: The commitment of resources; human, material, and capital, required to construct 

the network of pipelines and wells for a project that is most likely 

energetically untenable, cannot be supported without a proper evaluation of 

carbon throughput of the entire process. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Mary Munn 

Commenter Organization: Fond du Lac Reservation 

EPA Letter ID: 0347 

EPA Comment ID: 27903 

Comment: This rule is written for the existing energy production system. The reliance on 

fossil energy must change to meet the challenge of climate change. Barriers to 

the success of alternate sources of energy must be removed so the issue can be 

faced head on. This rule will impede and obstruct progress for those competing 

industries. 

The resources required to pursue this undertaking will be in direct competition 

with efforts focused on sustainable energy sources and alternative, arguably 

more effective carbon sequestration, utilizing wetland restoration, improved 

agricultural methods, and sustainable forestry practices that have numerous and 

vital fringe benefits. 

Experts in carbon sequestration know that utilizing biologic methods of carbon 

capture is cost effective and will include economic benefits. For example, 

596
wetland protection and restoration will not only sequester carbon but will 

purify water, impede drainage (flooding), and replenish aquifers. Many avenues 

could be used to reverse engineer the activities that drained these wetlands. 

Many studies including the Kyoto Protocol Wetland Restoration and Management and 

the Wilderness Society Forest Carbon Report support these alternative carbon 

sequestration mechanisms. 

Reduction of carbon emissions to the atmosphere is the primary driver for this 

new class of well, proof that carbon capture and sequestration will provide a 

net removal of CO2 must be provided else any reference to the reduction of CO2 

emissions or climate mitigation must be removed from the document. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Verne Shortell 

Commenter Organization: NRG Energy, Inc. 

EPA Letter ID: 0360 

EPA Comment ID: 28237 

Comment: 20 million homes. NRG believes that emissions of GHGs from power generation and 

other sectors must be reduced, both domestically and internationally, to 

successfully address climate change, and that commercially attractive, safe and 

environmentally secure carbon capture and sequestration will be critical for 

that success. Headquartered in Princeton, NJ, NRG is a member of the U.S. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

597
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28246 

Comment: a more comprehensive regulatory approach to as rulemaking. In particular, we 

urge that the Agency consider the potential applicability of Federal Statutes 

that would address various aspects of sub-seabed GS. 

Regulation of sub-seabed geological sequestration of CO2 

Whether EP A pursues a stand-alone UIC GS rulemaking or a more comprehensive 

regulatory approach, we urge that the EPA include in its rulemaking provisions 

that would address issues related to sub-seabed GS of CO2. 

Regulation under a stand-alone UIC GS rulemaking. 

According to the July 25, 2008 proposed rulemaking, the proposal applies to 

injection wells in the U.S. including those in State territorial waters. Deep 

saline aquifers offshore New Jersey have been identified by geologists as 

potential sub-seabed GS sites, both in New Jersey State territorial waters and 

in Federal waters. 

In New Jersey, as well as some other coastal States, some geological formations 

that serve as onshore USDWs extend offshore beneath the seabed. Given that fact, 

is imperative that a regulations pertaining to GS for the purposes of protecting 

USDWs must take into account conditions in the marine environment that may 

impact geologic siting requirements, Area of Review, well construction and 

operation; mechanical integrity testing and monitoring; well plugging; postinjection site care; plume monitoring, measurement and verification, and site 

closure. 

In addition, regulations should take into account a number of potential 

scenarios that could occur in coastal areas with respect to the spatial 

relationship between the injection site and the sequestration site. 

Specifically, the injection site may be located onshore or offshore, and the 

sequestration site may be located onshore or offshore. 

In the case of an onshore injection site, the sequestration site may be either 

598
offshore in State territorial waters, offshore in Federal waters, or may 

straddle State and Federal waters. When the injection site is onshore, transport 

of CO2 to the sequestration site may involve a pipeline that is situated either 

on the seabed or sub-seabed. The proposed rule does not address issues of 

pipeline integrity, monitoring, or remediation. 

In the case of an offshore injection site in State waters, the sequestration 

site may be located in State waters, Federal waters, or may straddle State and 

Federal waters. Issues of pipeline integrity arise if injection is in State 

waters and sequestration is in Federal waters. 

All of these scenarios raise potential issues of contamination ofUSDWs. We urge 

the EPA to consider differences between terrestrial and marine environments when 

considering appropriate regulations for GS. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28247 

Other EPA Comment Codes and Descriptions: 1100 1.1 Comments on the Comprehensive 

Approach 

Comment: Regulation under a more comprehensive regulatory framework 

The July 25, 2005 proposed rule indicates that wells up to three miles offshore 

may be subject to other authorities or may require approval under other 

authorities. It appears from the proposal that wells located outside of State 

territorial waters would not be regulated under this proposal. We recommend that 

EP A consider the potential applicability of Federal Statutes that would address 

various aspects of sub-seabed as both in State and Federal waters in its 

599
rulemaking. 

Individual Response: The GS rulemaking, promulgated under SDWA authority, applies to owners 

and operators of injection wells used for GS of CO2, including those in state territorial waters. 

Injection wells outside of state territorial waters may be subject to other federal authorities. For 

example, sub-seabed CO2 injection for GS may, in certain circumstances, be defined as ocean 

dumping and subject to regulation under the Marine Protection, Research, and Sanctuaries Act. EPA 

adds that the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEM), formerly 

the Minerals Management Service, administers the Outer Continental Shelf Lands Act (OCSLA), which 

provides for the grant of leases, easements, or rights-of-way on the outer continental shelf to the 

extent that an activity “supports production, transportation, or transmission of energy from sources 

other than oil and gas” and complies with the other provisions of OCSLA section 8(p). 

EPA acknowledges that GS falls within the broader context of CCS and the need for regulatory clarity 

to ensure that USDWs are protected from endangerment. In developing the final GS rule, the Office of 

Water coordinated with other Agency program offices and across federal agencies (e.g., with the 

Department of Energy; United States Geological Survey; Bureau of Ocean Energy Management, 

Regulation, and Enforcement, formerly the Minerals Management Service; and the Bureau of Land 

Management). The Agency continues to evaluate areas of potential applicability of other Federal 

environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and 

Recovery Act; the Comprehensive Environmental Response, Compensation, and Liability Act; and the 

Marine Protection, Research, and Sanctuaries Act to various aspects of GS and CCS. The Agency will 

continue to coordinate on GS and CCS-related issues to minimize redundancy and maximize 

efficiencies for owners or operators. For additional information, please see the discussion entitled 

"How Does This Rulemaking Relate to Other Federal Authorities and GS and CCS Activities?" in the 

preamble to the final GS rule. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 28-SEP-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jeanne Herb 

Commenter Organization: New Jersey Department of Environmental Protection (NJDEP) 

EPA Letter ID: 0361 

EPA Comment ID: 28249 

Comment: Given the USDOE's demonstrated interest in pursuing sub-seabed storage ofCO2, 

and given the likeliness that some sequestration sites (and their associated 

600
CO2plumes) will either be in Federal waters, or will straddle State and Federal 

waters, it is imperative that a regulatory framework be put in place that will 

address issues associated with these conditions. 

Federal Statutes that may have applicability include, but may not be limited to, 

the Marine Protection Research and Sanctuaries Act, relating to regulation of 

dumping of materials into ocean waters; and the Outer Continental Shelf Lands 

Act, relating to U.S. Department of Interior authority to issue leases for 

activities on the Outer Continental Shelf relating to energy sources other than 

oil and gas. A proposed regulatory framework should address issues of 

jurisdiction where more than one Federal agency may have authority over 

protection of marine environments 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott L. Davis 

Commenter Organization: Arizona Public Service Company (APS), Environmental Health and Safety 

EPA Letter ID: 0363 

EPA Comment ID: 28269 

Comment: Arizona Public Service Company (APS) owns or operates a number of fossil fuelfired power plants, including two large coal-fired power plants. APS strongly 

supports aggressive research and development of viable methods for carbon 

capture and sequestration (CCS) projects and for reuse CO2 from fossil 

generation plants. APS has worked with Westcarb and other Arizona utilities on a 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

601
______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0365 

EPA Comment ID: 28281 

Comment: utilities of all sizes that serve more than 90% of the U.S. population. Climate 

change will have significant impacts on water resources and while we recognize 

the need for strategies to address mitigation of greenhouse gases (GHG), we also 

strongly believe that any strategy deployed for this purpose should protect our 

water resources above all else. 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Scott Anderson 

Commenter Organization: Environmental Defense Fund (EDF) 

EPA Letter ID: 0376 

EPA Comment ID: 28164 

Comment: Our organizations continue to believe strongly that geologic sequestration of 

CO2 (GS), correctly implemented, must be a component of the U.S. climate 

mitigation portfolio. For that reason, we continue to stress the importance of 

the current rulemaking and the timely promulgation of a sound rule, as we stated 

in our joint comments of December 2008 and June 26, 2009. We reiterate the need 

for EPA to (1) address the question of atmospheric emissions of CO2 as well as 

protection of underground sources of drinking water related to underground CO2 

injection without delaying promulgation of the pending rule, (2) create a 

regulatory framework for geologic sequestration, governing not only geologic 

sequestration in saline reservoirs, but also in oil & gas reservoirs, and (3) 

expeditiously develop airside accounting, monitoring and reporting provisions 

602
for injected CO2 [FOOTNOTE 1]. We are somewhat encouraged by EPA’s statements 

Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is 

outside the scope of the Notice of Data Availability. Please see responses to comments on the 

proposed rule for EPA’s response to similar comments.

In addition, portions of this comment are outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 24-AUG-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28101 

Comment: However, moving forward on climate change mitigation must not come at the 

expense of the country’s water supplies or water quality. Protecting our 

nation’s water supplies from potential negative impacts resulting from the 

development of carbon sequestration projects is of paramount importance. We 

urge EPA to be protective of public health and to base its regulatory decisions 

on sound scientific evidence in structuring this rule, so that the promulgated 

rule ensures the availability of current and potential future drinking water 

aquifers, recognizing that water managers are faced with difficult challenges in 

light of shrinking and changing water supplies due to climate change impacts. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

603
Commenter Name: Diane VanDe Hei 

Commenter Organization: Association of Metropolitan Water Agencies (AMWA) 

EPA Letter ID: 0383 

EPA Comment ID: 28111 

Comment: In closing, as AMWA has commented before, many strategies must be used to reduce 

GHG - from conservation to alternative energy sources. Carbon capture and 

sequestration may be one tool in the toolbox, but it is not the silver bullet. 

Over two decades ago, MTBE was championed as the panacea to meet Clean Air Act 

requirements only to prove poisonous for many of the nation’s groundwater 

supplies. Therefore, careful research, data gathering and modeling and a 

commitment of long-term financial responsibility must be accomplished in advance 

of deployment of GS or the allowance for waivers. 

It is good and necessary for our nation to increase mitigation of GHG emissions. 

However, the desire to mitigate GHGs cannot preclude or worsen our ability to 

adapt to climate change, particularly as climate change is currently affecting 

the hydrologic cycle and in many cases, adversely impacting water supplies. 

Again, AMWA appreciates the opportunity to comment on EPA’s NODA. If there are 

any questions about our comments please contact me or Erica Brown, Director of 

Regulatory Affairs and Scientific Program Development, at 202-331-2820. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Kristin Henry 

Commenter Organization: Sierra Club, Environmental Law Program 

EPA Letter ID: 0388 

EPA Comment ID: 28295 

Comment: Sierra Club continues to believe that that Carbon Capture and Sequestration 

(CCS) could play an important role in allowing deep greenhouse gas emission 

reductions from electric generation and industrial facilities. Scientists agree 

604
that in order to avoid the worst consequences of climate change, the United 

States must cut greenhouse gas emissions at least 80 percent below 2000 levels 

by 2050.[FOOTNOTE 1] The scale of CCS projects necessary in the electricity sector to 

achieve this objective is enormous. 

However, to have any meaningful role in curbing greenhouse gas emissions, CCS 

projects must proceed quickly while cognizant that there is no room for 

missteps. A team of international experts recently explained that "a single 

major accident, resulting from inadequate regulatory oversight, anywhere in the 

world, could seriously endanger the future viability of GS [geologic 

sequestration]." [FOOTNOTE 2] In order to ensure that there are no missteps, 

Sierra Club recommends a few critical changes to the proposed rule and the 

changes specified in the NODA. 

[FOOTNOTE 1]: Luers, A.L. et al. 2007, How to Avoid Dangerous Climate Change: A 

target for U.S. emissions reductions. Union of Concerned Scientists, online at 

http://www.ucsusa.org/assets/documents/global_warming/emissions-targetreport.pdf 

[FOOTNOTE 2]: Wilson, E., Morgan, M. et al., Regulating the Geological 

Sequestration of CO2, Environmental Science & Technology, Apr. 15, 2008, at p. 5 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

______________________________________________________________________________________

____________________________________________________ 

Commenter Name: Jim Stovall 

Commenter Organization: 

EPA Letter ID: 0389 

EPA Comment ID: 28307 

Comment: Comments Outside the Scope of the Rule. 

We have a few concerns that are outside the Scope of the Rule. These are risks 

to human health, air, ecosystems; and illegal dumps. 

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We recommend that a detailed Risk Assessment be performed that covers all 

aspects of the CS operation, from cradle to grave. This assessment should 

specifically address the risks to: human health; animals above ground; impacts 

to ecosystems above and below ground; mobilization of metals; ground heave; and 

induced seismicity. Perception is half of the battle, and we also suggest that 

the public be much involved in the development of this assessment. 

Illegal dumping of petroleum products is a concern within this office. Many of 

the sites of illegal dumping have been reported from the public and from field 

going personnel within the office. There always exits some type of evidence on 

the ground resulting from these dump sites; however, in the case of carbon 

dioxide in a gas phase, direct evidence would be difficult to obtain. We suggest 

emphasis on the accounting of carbon dioxide from the source of the stream to 

the injection site. 

Individual Response: This comment is outside the scope of the Notice of Data Availability and the 

UIC Program’s authority under the GS rulemaking. 

EPA Team Member: 

Draft Status: 

Date Uploaded: 15-JAN-10 

Notes: 

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