## 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 (c omme nt 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 N otice o f D ata Availability a nd R equest f or C omment (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 El ements 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 3 230
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

### 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 400 0
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 Propo sed 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 Require ments (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 Requi rements (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.

R esponses to letters from individual commenters or organizations are also available in
the rulemaking docke t.

## Comment Response Report by Comment Code

Search Te rms: Starting EPA Comment Code: 1000 Ending EPA Comment Code: 6000

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

**************************************************** EPA Comment Code: 1000 1. General Comments on t he 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 pr ogram, 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

- HQ

OW- 2008

- 0390

- 391). EPA also afforded all members of the public the same opportunity to comment

online and b y mail through the public docket regardless of whether they attended the hearing in
Chicago.

EPA Team Member:

Draft Status:
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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 ru le 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 di fferent 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Dwight N. Lockwood
Commenter Organization: Global Energy, Inc.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 experi ence 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 re sponses to comments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James J. Dooley
Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National
Laboratory

EPA Letter ID: 0334

EPA Comment ID: 2 8203

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 propos ed
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 mos t 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, da ta, 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

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Notes:______________________________________________________________________________________

____________________________________________________ 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 CO 2 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 regulator y 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 ab out 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 ap proach 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 si te

specific 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara A. Walz
Commenter Organization: Tri

- State Generation and Transmission Association, Inc. ( Tri

- State)

EPA Letter ID: 0346

EPA Comment ID: 27888Comment: Tri

- State applauds EPA's careful approach to the development of CO2 GS
regulations, including this most recent release of ad ditional 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 mo st 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 site

specific 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

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Not es:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James F. Stine
Commenter Organization: National Rural Electric Cooperative Association

EPA Le tter 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 additiona l 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 technologyrelated to carbon sequestration. It is critical that EPA develop a regulatory
regime incorporating p erformance

- 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 beli eves 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 site

specific characteris tics. 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

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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 c ommercially 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.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 site

specific 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

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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 d evelopment 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 ac commodate
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

v ast 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 site

specific characteristics. For additional information on the adaptive approach and site

- specific
requirements, see the resp onses to comments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 21

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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 flexi ble 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 t o 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 site

specific characteristics. For additional information on the adaptive approach and site

- specific
requiremen ts, see the responses to comments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:Date Uploaded: 21

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- 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 site

specific characteristics. For additional information on the adaptive approach and site

- specific
requirem ents, see the responses to comments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 21

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Verne Shortell
Commenter Organization: NRG Energy, Inc.EPA Letter ID: 0360

EPA Comment ID: 28239
Other EPA Comment Codes and Descripti ons: 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 contemplat ed 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 th e 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 informa tion 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 revie w 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 site

specific 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 Upl oaded: 30

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Smith
Commenter Organization: Questar Exploration & Production Compa ny

EPA Letter ID: 0374

EPA Comment ID: 28117Comment: The preliminary field data from DOE

- sponsored projects, GS

- related research and
changes EPA is proposing for injection depth require ments 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 i n 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 indu stry 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 natu re 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 rulema king docket.

EPA Team Member:

Draft Status:
Date Uploaded: 04

- OCT

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson

Com menter 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

incl uded 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 achi eved: we note particularly the new definition of
"carbon capture and storage" [FOOTNOTE 6] which is not found in the proposedregulatory text and confusingly includes the word "storage" rather than
"sequestration" making it inconsistent with the regulat ory 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 re commendations
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

fluid s, 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 pressu re 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 an d 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 d efinitions, see the responses to comments on the proposed rule in
the rulemaking docket.EPA Team Member:

Draft Status:
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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environmental Defense Fund (EDF)

EPA Letter ID: 0376

EPA Comment ID: 28178

Comment: E. Con clusion

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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: R ebecca Thingelstad
Commenter Organization: Anadarko Petroleum Corporation (APC)

EPA Letter ID: 0380

EPA Comment ID: 28090Comment: 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 en hanced 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 f or 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 develo ped 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 e xperience 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 f or 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 establishe s 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 Tea m Member:

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Notes:______________________________________________________________________________________

____________________________________________________ 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 an d 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organizati on: Edison Electric Institute (EEI)

EPA Letter ID: 0384

EPA Comment ID: 28121Comment: 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 regula tory 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 b alance 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.

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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 pr omote 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 co mmercial

- 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 sitecare 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 indef inite 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 promot e 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.

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

that will demonstrate that these characteristics are av oided. 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 coo rdinated 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 o f 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 owner s 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

hazardo us 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:

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Date Uploaded: 05

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N otes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James J. Dooley
Commenter Organization: Joint Global Change Research Institute, Pacific Northwest National
LaboratoryEPA 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: Completio n 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 ot her 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:

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Patrick J. Nugent
Commenter Organization: Texas Pipeline Ass ociation (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 s evere 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 regulator y 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 th e 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 Sanctu aries 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 Do es 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 pr ocess 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 whethe r 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 r ule 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

t hreshold 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:

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Date Uploaded: 05

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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 comprehen sive 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 theextent 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 -O AR

- 2005 0161), 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 effici ent 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 redun dancy
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 Tea m Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. Sims
Commenter Organization: W estern 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, poli cy 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 andstate regulatory bodies and the public will app roach 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

t he 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 Environ mental 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:

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Date Uploaded: 28

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. Sims
Commenter Organization: Western Business Roundtable

EP A 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.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 le vel 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
importan t 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.

Indiv idual 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 pr ogram 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 Agenc y 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

Liabi lity 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 characteriz e 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 w hich 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 underthe 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:

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Date Uploaded: 05

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Pamela F. Faggert
Commenter Orga nization: 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 n eed 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 Environmen tal 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 a n 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 con tinue 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 a nd CCS
Activities?" in the preamble to the final GS rule.

EPA Team Member:Draft Status:
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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) Pr ogram 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

u nderground 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 aspe cts 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 wit hin 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., w ith 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, andLiability Act; and the Marine Protection, Resea rch, 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

- seabe d 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, tr ansportation,
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 Au thorities and GS and CCS Activities?" in the preamble to the final GS rule.

EPA Team Member:

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Date Uploaded: 28

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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 sub ject 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 appl icability of Federal Statutes that would address
various aspects of sub

- seabed as both in State and Federal waters in its
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 o il 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 G S 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 Minera ls 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 Ac t; 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 redunda ncy 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Michael Moore
Commenter Organization: Nor th 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 ef forts to move forward with bringing regulatorycertainty 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 red undancy
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 T eam Member:

Draft Status:
Date Uploaded: 21

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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 com prehensive
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 previ ous comments include a discussion of regulatory andliability 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

reg ulation holistically and avoid piecemeal regulation. We note that Agency's final rule on Mandatory Reporting of Greenhouse Gases (Docket ID No. EPA

- HQ ORA

- 2008

- 0508), released on September 22, 2009, references the Agency's intent
to "issue a new propos al" 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 piecemea l 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 "end eavor 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 Respons e: 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 t o 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

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environmental Defense Fund (EDF)

EPA Letter ID: 0376

EP A 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 det ails, 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).

Individ ual 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 prog ram 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

Liabili ty 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 i nformation, 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 separaterulemaking 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

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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 app licability 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:Date Uploaded: 21

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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 Fr amework 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 t o 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 ar ising 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 ofcritical 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 t he 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 rulema king 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 acknowl edges 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 fe deral 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 are as 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 th e 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:Date Uploaded: 21

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organization: Spectra Energy Corp

EPA Letter ID: 0385

EPA Comment ID: 28150

Comment: III. Comments on the n eed 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 believe s 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 t hat 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 CCSAc tivities?" in the preamble to the final GS rule.

EPA Team Member:

Draft Status:
Date Uploaded: 21

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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), th e 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 hazardou s 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 includesignificant 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 Co ntingent 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

tox icity 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 abovethe 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 inc lude
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; rat her, 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: R egarding 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 Me mber:

Draft Status:
Date Uploaded: 05

- OCT

- 10

Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Kristin Henry
Commenter Organization: Sierr a 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 recognize s 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, a nd 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 associa ted 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 w ater" 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 uni verse of issues
involved with large

- scale CCS implementation such as capture, transportation andpipeline 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 shou ld 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 permitt ed 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 hazardo us 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 s hould 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 protecte d 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 C CS 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:Date Uploaded: 21 -S EP

- 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 t o 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 stor age.

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 th e 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: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 Servic es, 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 St orage. 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 thatChapter 5 of the re port discusses many of the technical issues related to siting, constructing, and
monitoring GS wells.

EPA Team Member:

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Notes: This comment contains text from two non

- consecutive parts of the letter, line 109 and l ines

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 w hile 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:

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Notes:

______________________________________________________________________________________

____________________________________________________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 experim ental 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 site

specific approac hes 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 th e 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.

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______________________________________________________________________________________

____________________________________________________ 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 performedpurely 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 rais ed
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 site

specific approaches to ensure that appropriate construction, operation, and monitoring is perform ed 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:

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis
Commenter Organization: American Water Works Association (AWWA)

EPA Letter ID: 0369

EPA Comment ID: 27934

Co mment: 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 la rge- 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 potent ial 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 magnitudesof scale smaller than the sort of projects envisio ned 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 op erations (from well construction and injection to long

- term plume fate and transport and monitoring of containment) to inform the GS rule.

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______________________________________________________________________________________

____________________________________________________ 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 int o 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 mo deling
(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 realizedIndividual 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

m odeling 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 appropri ate amount and types of
information and appropriate documentation are being collected, and to determine if modifications to
the requirements are appropriate or necessary.

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____________________________________________________ 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 s tudies 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

s upport EPA proceeding with final rule promulgation.Individual Response: EPA acknowledges the comment and agrees that sufficient data exist on which
to base final requirements for GS at this time.

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______________________________________________________________________________________

____________________________________________________ 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 d ifferent 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 c ommercial scale 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 agr ees 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 an d review data on GS projects to determine whether the appropriate amount and
types of information and appropriate documentation are being collected, and to determine ifmodifications to the requirements are appropriate or necessary.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequest ration 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 in vestigations 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

pat hways 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

ove r 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 tha t 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.

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______________________________________________________________________________________

____________________________________________________ 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 availabi lity 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 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 r equirements for GS wells.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 amo unt and types of information and appropriate documentation are being
collected, and to determine if modifications to the requirements are appropriate or necessary.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Harold Buckley
Commenter Organization: Edison Electric Institute

EPA Letter ID: 0540

EPA Comme nt 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 a pplication 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 whe ther 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:

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Notes:**************************************************************************************

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

EPA Comment Code: 2100 2.1 DOE Regional Carbon Sequestration Partnership Projects

EPA Team Member:

Draft Status:
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Notes:

Comment Summary:

Response to Comment Code:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Na me: 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 regar ding 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 C O2 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 de vices, 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.co m], 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 proje cts.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 sea ms. 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

inf ormation and appropriate documentation are being collected, and to determine if modifications to
the requirements are appropriate or necessary.

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Notes: This comment contains text from two non

- conse cutive 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. McManusCommenter 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 deter mine 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 requir ement 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 contex t.
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 asite

- 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 monitor ing requirements for the GS wells at §146.90 incorporate elements of pre

existing 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.

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______________________________________________________________________________________

____________________________________________________ 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 ca rbon 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. W e are concerned, however, that this NODA may be premature, as it reflects data fromonly 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 asso ciated 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 prio r 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 c ollect 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.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Edward Steadman
Commenter Organization: Ene rgy & 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 "act ively tracking the progress" of the RCSP's projects. As the RCSPsare 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 fin alizing 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

constr uction 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 techn ologies, 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 de lay 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.

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______________________________________________________________________________________

____________________________________________________ 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 captur e, 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 i njected 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 a ny 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 exp eriences 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 C O2 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 informatio n available
for public review and comment in a subsequent NODA prior to promulgation of a

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 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 belie ves 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.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Jeanne Herb
Commenter Organization: New Jersey Department of Environmental Protect ion (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 demons tration 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 bou ndaries 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,including offshore projects.

EPA has been cooperating with the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEM), formerly the Minerals Management Servic e, 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).

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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
project s, 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 drin king 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, f or 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 employ ing requirements for their use in Class VI projects. The proposed
regulations likewise proposed granting discretion to the program director torequire the use of tracers and/or surface air/soil gas monitoring. As detailed
in NACCSA's prior comments, thi s 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.

Indivi dual 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 pr ojects 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 technologie s, 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 monitorin g 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.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara Priest
Commenter Organization: Oregon Department of Envir onmental Quality (DEQ)

EPA Letter ID: 0366

EPA Comment ID: 27907Comment: DOE- Sponsored Regional Carbon Sequestration Partnership Projects (III.B.)

DEQ supports the pilot project appr oach 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.

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______________________________________________________________________________________

____________________________________________________ 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 regulato ry framework. This consideration, combined
with the abundant scientific evidence already considered by EPA in thedevelopment 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 char acterization, 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III

Commente r 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
Require ments (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 proje cts,
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 mo nitoring to detect movement of CO2, even where, as the Agencyproposed, 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 authorit y 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 necess arily 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 ab out 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
pl an 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 appr opriate 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.

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organization: Spectra Energy Corp

EPA Letter ID: 0385

EPA Comment ID: 2814 5
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 res earch 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 po stponed 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.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 wh ether 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.

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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 implementat ion of CCS and do
not reflect industry's 35

- plus years of success in injecting CO2 under the ClassII UIC program. [Footnote 1] The Class II EOR wells constructed for these CO2
injection projects - and their operating practices - have an excellent recor d 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. F or 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

p roposed rule for additional information on EPA’s final approach to construction of GS wells.

EPA Team Member:

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: American Petroleum Institute (API)

EPA Letter ID: 0350

EPA Comment ID: 28040

Other EP A 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 c ircumstances. Natural CO2 concentration in soil can
have high spatial and temporal variation resulting from complex environmentalinteractions, 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 a t 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.

[Foot note 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 viab le 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 ne ed 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 variabi lity 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. Se e 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike PaqueCommenter 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 standard s 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 doe s 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 pro posed 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:

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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 requirementsEPA has noted in the NODA that the SECARB project "employs, demonstrates, and
validates the EPA’s p roposed 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 voluntari ly 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 prescriptiv e 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
requireme nts 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 w ells 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 CO 2 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 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.

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Note s:

______________________________________________________________________________________

____________________________________________________ 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 pil ot
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 th e 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 ackno wledges 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 th e 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:

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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 databa se 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 t heproject, 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 determi ne 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 wa ste 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 p roject 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

con struction 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 requ ired 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 t he construction recommendations presented in the MSD
Recommendation Letters of May 14, 2009 and May 15, 2009.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

i njection 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 anticip ated 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 stora ge 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 informati on 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organization: Edison Electric Institute (EEI)

EPA Let ter 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 projec t 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 monit oring 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 hasfound "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 d etailed 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 C lass 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.

Individua l 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 resul ts 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

line s 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: 0540EPA Comment ID: 28315
Other EPA Comment Codes and Descriptions: 2120 2.1.2. S WP (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

trac ers 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 a bout 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

p lan 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 endanger ment 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 do cument 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: 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 requirem ents
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 wel ls 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 bu rdensome, 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 charact eristics of CO2 including itsbuoyancy 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 monitorin g 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 t o detect mobilization of metals and dissolution of CO2 in
subsurface brine. See the response to comments document for the proposed rule for additionalinformation 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 (A PI)

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 s pecific. 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 Au stin, 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 mon itoring 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 wha t 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 s ites.

EPA Team Member:

Draft Status:
Date Uploaded: 21

- SEP

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Rebecca Thingelstad

Comme nter 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 indu strial 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 robustmonitoring 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 me thods 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 Org anization: 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 o f anexisting 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 p lan, 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 Projec t, 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 m onitoring 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 t hese 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.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 determ ine 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, II I
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 it s 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 setti ngs.

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.______________________________________________________________________________________

____________________________________________________ Commenter Name: Harold Buckley
Commenter Organization: Edison Electric Institut e

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 re quirements 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

monitorin g 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 appro priate 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 uniqu e 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 theproposed 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

Comme nt: 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

necessari ly 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 m ore 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.Indivi dual 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

- spec ific 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 tra cers 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 tes ting 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 believ es 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 Partne rships 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

thi s project are pending and given the quantities injected it is unclear to usthat 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 con cerns 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 characterizatio n 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.

T he Pump Canyon Project represents just one test of traces; the outcome shouldnot 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 i nvolved 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 Director

approved testing and monitoring plan. See the response to comments documen t 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 VoorheesCo mmenter 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 comme nt 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 injecti on 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 conditio ns 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 tho se 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: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 Com ment 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, D ata 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

describ ed 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 explai ned 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 regulatoryframework, 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 end angerment 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 yea rs, 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 T eam Member:

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______________________________________________________________________________________

____________________________________________________ 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 current ly 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 sequest ration 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 adapt ive 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 docum entation
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 areappropriate or necessary.

EPA Team Member:

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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 pol icy 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 far field 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 accep table 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 pendi ng 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 Directo r 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 p ossible
increase in risk for the containment of the total CO2 and/or the effects of hydraulic perturbations and
brine displacement.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 sequestratio n 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 sco pe 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 Depa rtment of Energy.

EPA Team Member:

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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______________________________________________________________________________________

____________________________________________________ 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 LB NL 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 st udies 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 fo cused 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 t o 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 certai n 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. Furtherm ore, 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 leakagerate is very small compared to the expected volume of CO2 in geologic storage r eservoirs, 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

info rmation 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:

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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 wil lfully 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,

ef

fective 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 rul e 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/oratmospheric monitoring), and after injection (via similar techniques) to
identify leakage in time to allow mitigation efforts well in ad vance 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

ass umptions 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 Adva nce 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., pre

injection site characterization may fail to detect leakage pathway or monitoring during and after
injec tion 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 sci entific 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 reduct ion 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,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 rulem aking docket.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower

Com menter 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 n ot 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 thes e 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 wat ers 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 theprobability 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 wit h
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 re sults - 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 f orm 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 mobiliz ation
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

- 192 4.

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 pr essures 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 specifiedCO2 par tial 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 t hat 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 a nd 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 t he 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 m ay 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 stu dies, 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. Ho wever, 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 aq uifer 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 geoch emical 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 t hat 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 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 pro vides 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 gro undwater 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

arse nic 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 chil dren, 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 homesand schools due to corrosion of plumbing fixtures. Any increase in raw water
lead concentration constrains the utility in compliance with its optimized

corro sion 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 long term 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 o r 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 o f 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 MC Ls 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 t o 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 objec tiveor 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 qu estion 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

u nlikely. 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 sp ecies 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 co

precipitation of many of the cited hazardous elements, and could actually decrease their
concentrations to levels lower than present in uncontami nated water. This phenomenon, while
theorized, has neither been modeled nor evaluated experimentally.

EPA Team Member:

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Date Uploaded: 20

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Notes:______________________________________________________________________________________

____________________________________________________ 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 impa cts 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 treat ment 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 non compliance with the lead and copper rule, even if the lead is below the action

level.

- LBNL did not eval uate 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 currentlycome 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

stud y 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 n ecessary.

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:
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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 rec ognize 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 formati on 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.Individual Response: EPA agrees that contamination of USDWs would not be a c oncern 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

asso ciated 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 c onfining 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 well s, see the responses to
comments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 20

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- 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 d o 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
"represent ative" 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.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. Specifi cally,
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 ro ck 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,

includin g 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

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Rebecca Thingelstad
Commenter Organization: Anadarko Petroleum Corporation (APC)

EPA Letter ID: 0380

EPA Comment ID: 28096Comment: 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 con ducted 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.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

con centrations 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 tra ce 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 de termine 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 incr eased 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, howeverunlikely, 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

Com ment: 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 t race 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. (20 09), 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¬trationsin 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

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- 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 concentr ations 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 repres entative.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 el ements 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 ge nerally 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 anal ytical 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 minera logy 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 US GS 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 ofall GS sites, and believes that site

- speci fic 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, perme ability,
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 mineral s 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 chara cterization for GS wells, see the responses to comments on the proposed rule in
the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 28

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Comment ID: 27963

Co mment: 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 f ew 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 rea listic scenarios
are developed and particularly as the methods can be tested with actual projectsite 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 do cumentation 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 T eam Member:

Draft Status:
Date Uploaded: 21

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organizatio n: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Comment ID: 27964

Comment: Comment No. 16

Page 44807

Issue Topic from EPA's NODAIt is important to emphasize that these st udies 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 probabiliti es 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 si te

- 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 rep resents 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 resul ts
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 verifie d 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 du ring the loss of containment for a CCSreservoir.

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 add itional investigations could be conducted (e.g., regarding the co

migration 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 documen tation 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

c omments on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 28

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Comment ID: 27965Comment: 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 refer ences (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 - pre sented 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.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.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 scree ning 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 short term 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 migrati on into drinking water aquifers might have with respect to mobilizing
trace elements and exceeding drinking water standards. The authorswere very clear that the study was conducted as a screening level
assessment. The scope of this particular study wa s 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 conclusio n 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 sho wed 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 t hat 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

unsubstantiate d.- 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 i n 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 concentration s 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 aqui fer. 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 effortworthwhile.

o Thermodynamic analysis of water samples:

o Assessing the saturation state and solubility of various miner al
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 a nd 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.
(2 008), 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 immin ent 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 necessa rily 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 LB NL 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 overal l 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 thosefound in coal and ore materials; they actually teste d 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 aq uifer 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 o f 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 le ad
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 subs equent 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 nat ural variability of field data from the NWIS database.

EPA Team Member:

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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 st ates 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 fordrinking water utilities or for public health. This is emphatically not the
case, as simply the presence of these contaminates would further degrade the

suitabilit y 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 refe rence 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 maxim ize 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 fo r 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

ho st 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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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

i n 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[actionlevel]." [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 loo ked 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]

[Foot note 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

sele cted 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

- specifi c 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kristin Henry
Commenter Organization: Sierra Club, Environmental Law Program

EPA Letter ID: 0388

EPA Comment ID: 2829 8

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.

Th e 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.

Individua l 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 comment s on the proposed rule in the rulemaking docket.EPA Team Member:

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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 Lawrenc e 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 devel oped 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, sit especific 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.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.

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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 result s are unsubstantiated.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 necess ary 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). 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:

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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 an d 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 i njection 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 increaseabove 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:

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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 o f 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 ma y have to be in proximity to eachother. 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 site

specific 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:

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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 difficul t 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 B IRKHOLZER, J.T., Q.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 Post Combustion 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 deplo yment 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 o f 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 th e 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 preve nt 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 deve lop 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 subseq uent
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 fo r 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 re present future reality. As an academic exercise toeducate 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 importa nt.

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, eve n 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 sedi mentary 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 i mpacts 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 f ar

- field pressure perturbation away from the basin center would be

similar.EPA agrees that proactive management of basin scale concerns to maintain pressures within
acceptable ranges is important, and encourages owners or operators and permitting authori ties 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 t he 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert J. Finley
Commenter Organiza tion: 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 pe rturbations 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 studiesbut 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 col lection 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

m m/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 c hosen
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 in jection area, thus recent data would tend to reduce the pressure affected 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 capacit y 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 reso urce assessments would represent actual capacity. The authors statement that theseresource estimates are subject to "an implicit assumption that the storage
capacity is not constrained by pressure buildup and brine migration..." is

incorrect, and rese archers 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 k ey 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 ackn owledges the need for improvement/validation of predictive models before considering basin

scale 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 ev en 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 th e 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

th eir 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
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 -2 0 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.

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______________________________________________________________________________________

____________________________________________________ Commenter Nam e: 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 b reathing 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 fo r subsurface gas migration.

Findings:

Confining layer(s) for fluids (water or oil) may not confine CO2

- type gases.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 c atastrophic 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 i s 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.

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: Am erican 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 "illustr ates 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 constrain ts 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 sen se 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, Paleohy drogeology 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., a nd 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, andwould likely have been even lower if the model had included lateral
heterogeneities in permeability and porosity and used a hig her 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 t he 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
permeabilit y 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 well

consolidated sandstones at in situ effective stresses representative of Mt. Simon.Regardin g “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 discretizatio n 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.

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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."

E PRI 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 R esponse: 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, andencourages 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 p rojects 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.

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______________________________________________________________________________________

____________________________________________________ Comment er 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 b e 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.

Individ ual 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 accepta ble ranges is important, andencourages 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.

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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 o f 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 ex pected 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 bas in 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 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.

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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 Hydrologi c 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

- scal e 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 proactivemanagement of basin scale concerns to maintain pressures within acceptable ranges is important, and

encourag es 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, th e 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Rebecca Thingelstad

Commenter O rganization: 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 stu dy 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 base d 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 ou t- flow and far field pressure effects arevery 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 multi project basins where pressures fronts may intersect and influence. Adapt ive

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 conducte d.

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 displ acement. 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 predictio ns 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 b elieved 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 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.

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jean

- Philippe Nicot

C ommenter 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 basi n- 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

ope rators, 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 §14 6.84 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:

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Notes :______________________________________________________________________________________

____________________________________________________ Commenter Name: Jean

- Philippe Nicot
Commenter Organization: University of Texas at Austin, Bureau of Economic Ge ology (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 lay ers 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 int erest 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 si tes 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 ru le 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 t o communicate planned GS activities to maximize coordination and minimize pressure interference. If apermit applicant (or the permitting authority) is aware of pending GS projects near a proposed well,
the AoR delineation performed pursuant to §146.84 sho uld 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 d isplacement. 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 d eployment 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 appropri ate 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 stratigraphicunits. - 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, Paleohydroge ology 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., 200 6, 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 simul ation 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

corrobo rate 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,” numeric al dispersion is a concern for solute transport with sharp interfaces (advection

- dispersion equation) and/or for multi

- phase transport. For singlephase 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

P age 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 t his 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 multi project interference concerns if and when they occur.)Individual Response: The results of the modeling study did not cause EPA to change an y 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

interferenc e. 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 G S 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 cha nges 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 CommentsThe 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 obtain ed 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 wi thin the range of pore compressibility reported for well

consolidated 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 by400 km (249 miles by 249 miles) after 50 years. These model results in dicate

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 aquif er (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 pressur e 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 clarifi es 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 sign ificant 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 re search 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: 2 9162

Comment: Comment No. 22

Page 44808Issue 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 l ocalized 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

fo r 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 sto rage 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 ar tificial 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:Date Uploaded: 21

- JUL

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Com ment 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 potent ial 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 cr eate 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 signif icant 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

im provement 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 simulati on models that are indicators of large

- scale hydrologicimpacts. 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 spec ific 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 safeg uards 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

latera l 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. Recen t 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 pressure affected reg ion 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 brinemigration..." is incorrect, and researchers involved with creating these
estimates would be unlikely to agree wit h 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

re visions 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 basin

scale 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 operat ions 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 developme nt 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 project s 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 i n the basin

- scale modelused 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 capa cities) 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 Upl oaded: 21

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organization: Spectra Energy Corp

EPA Le tter 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 exampl e 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 f or 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 th e 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

- borderpartnerships.

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 seques tration 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 extrac tion, 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 po rous 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. Spect ra 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 basin level 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:- Expand existing collaboration in CO2 injection and storage testing,

share informati on 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 i ndividual 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 per formed
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 hydrau lic
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 recog nizes 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 t he 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 plan s. 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

Note s:

______________________________________________________________________________________

____________________________________________________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

Inte rstate 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 im pacts 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 propos ed 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 permittingauthority) 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 ap plication
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 loca ted.

EPA Team Member:

Draft Status:
Date Uploaded: 21

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- 10

Notes:

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

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

EPA Comment Code: 2300 2.3. Additional Rese arch

EPA Team Member:

Draft Status:
Date Uploaded: July 16, 2009

Notes:

Comment Summary:

Response to Comment Code:

### 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 trap s (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 CO2 for 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 "Carbo n 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.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

IP CC 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 retain ed 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 o ther 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 c ommitted to research and development of CCSin 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 attractiv e 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 leak age 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 e xhibit
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:

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EPA Comment Code: 2310 2.3.1. Review of Modeling Studies (seeking comment)

EPA Te am 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 andfails to take into account the modeling experience of industry. Industry is
constantly being faced with new situati ons 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, causi ng 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 i ndustry'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 intract able,
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 soft ware 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 storag e. 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 technicals ymposia 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 modeli ng. 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 nece ssary 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, a nd 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 peer

reviewed 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:

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______________________________________________________________________________________

____________________________________________________ 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 uniquechallenges" (NODA p. 44808). While on its face true, the statement exagge rates
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 experienc e 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 regula tions 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 i s 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 parti cular 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 CO 2 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

- isoth ermal, 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 a pplication.

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 aClass VI permit application. EPA clarifies that toda y’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 project s, 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 M ember:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Ca rbon 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, reac tive 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 safestorage.

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 analo gous 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 mult iphase 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 peer

reviewed modeling studies of GS available in the technical literature, including studies of GS in oil and
gas reservoirs, and studies using mo deling 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 Tea m Member:

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EPA Comment Code: 2320 2.3.2. Recent Publications on Ris k and Risk Management

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: 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, large scale 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 t hat "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 in tegrity 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 recove ry 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

- 03 j, 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 Re sponse: 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 t o 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 imp lementation 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 si te.

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 a n 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:

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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 thereo n 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 reservo ir

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, sc ope, 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 direc ting the resources from production tosequestration. 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 well s 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:

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Emily Rochon
Commenter Organization: Greenpeace Internation al

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 i ndicates 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, o ther than CO2, that are
present in a separated CO2 stream.

- Bjureby, E. et al. Reality Check on Carbon Storage, Greenpeace Publications(2009). Available at: www.greenpeace.org/utsira. By examining the world's
longest running CO2 storage project - th e 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 pe rmanent 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 i mplements 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: American Pe troleum 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 sa fety 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 th e 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 fo r 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 DigitalPublication 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 recogni zes 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 is sues associated with GS
through proper permitting, siting, well construction, operation, monitoring, and closure of GS projects.

EPA Team Member:

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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,C., an d 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 dio xide 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

sa mpling 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."EPRI COMMENT #3: As noted in the NODA, the Lawrence Berkeley National La boratory (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 groundwat er, 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

th e 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 w ater 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 t hat 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 recharg e 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.Theref ore, 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 a nd 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 project s.

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.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
incorpo rate 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

EP A 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 sequest ration 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.

Indiv idual 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 Sta tus:
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: 28273Comment: coal

- fired power plants. Over the last two years APS has worked with Westcarb

and o ther 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 b eneficial 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 an d 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 docke t.

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 d etails 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 res earchers.

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 groundwatergeochemistry 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 resu lts 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). Th e 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, we st Texas, USA, published at http://www.beg.utexas.edu/gccc/.

Our exa mination 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 w here 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 thatbackground variability in aquifers may mask the effects of even moderate
anthropogenic CO 2 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 aqu ifer. 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 ge ochemical shift is similar or

at least predictable in any geochemical environment even though processes and
mineralogies differ widely among aq uifers.

Indeed the position of many researchers is that a predictable consequence of
input of CO2 into a dil ute 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 large scale 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

an d 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 gr oundwater constituents must, at the very least, be

site

- specific and may not be useful at all owing to the variability andcomplexity of groundwater systems.

Research Objectives and Approach

To test methodologies for CO2 storage evaluation using shal low 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

g roundwater 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 C O2 input. In addition, we use stable

carbon isotopes to so urce

- identify dissolved CO2 to distinguish natural

microbial inputs from anthropogenic ones.

Methods

Approximately 113 fresh to slightly saline groundwater samples within Triassic age 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 oxy gen, 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 geochemist ry 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 injectedfor enhanced oil recovery, soil organic matter, and soil carbonate from Dockum

cor es 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

bri ne 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 exchan ge, 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 n ear? surface monitoring program. They illustrate the
importance of understanding hydrochemical context and b ackground 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 predi cted. 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 cal cite (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 wit h respect to calcite.
Input of CO2 into these very different systems has been modeled to produce verydifferent outcomes. In the simple system, DIC increases with increases in the
partial pressures of CO2 (PCO2) as previous researchers have predicted. H owever,

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

ge ochemical 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 dedolom itization

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 inp ut. 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 y ield definitive results. Hence

stable carbon isotopes do not appear to be the best t ool 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 an d 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 va riability 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 ofincreasing 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 gro undwater 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 B ulletin, 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 panhan dle, 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, Dedolomit ization reactions driven by

a nthropogenic 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 sys tems. 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.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 Proc edia, 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 Ge ology (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 thesoundness of the mo del 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 fres h- 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

e xtrapolations 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 o f 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 potenti al 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 wa nt to emphasize as being critical to studies of potential impacts to
drinking water resources from CO2 injection are:- CO2 occurs naturally in shallow aquifers. CO2 concentrations in a single
aquifer can vary temporally and spatially as a result of ag ricultural 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 z one.

- 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 Keat ing 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 res ult 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 b een 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 impa cts 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 aquiferfluid 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. Conc lusions 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 plum e 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 LB NL (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 potentiall y 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
throug hout 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 th e 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 (forinstances, 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

a ssemblages 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 am ount 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 com plexation (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 a nd 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 ar senopyrite existed in the rock samples. Lead, which according to the Birkholzer (2008)
could be the most problematic element after CO2 intrusion, however, is non detectable 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

numeric al modeling techniques is questionable and may be misleading if thecontrolling 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 solubi lity 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

Birkh olzer, 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 det ection 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 fo r 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 an alog 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, Enviro nmental 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 semiaridoxidizing system: Southern High Plains aquifer, Texas, USA: Applied
Geochemistry, doi:10.1016/j.apgeochem.2009.08.0004.

Shiraki, M., and Dun n, 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

distribut ion 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 Proce dia, 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., Spangenb erg, 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 o f 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:______________________________________________________________________________________

____________________________________________________ Commenter Name: Rebecca C. Smyth
Commenter Organization: University of Texas at Austin, Bureau of Economic Geology, J ackson

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 hav e 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 cond ucted 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

dete ct 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 a re 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 continueto 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 Seque stration 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 se e 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 andth e 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: Univers ity 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- 200 8- 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, Uni versity 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 roc k
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

concentr ations 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 categor ies. Type Ications?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. T ype 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 ac knowledges 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 M ember:

Draft Status:
Date Uploaded: 16

- JUL

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jiemin Lu
Commenter Organization: Universi ty 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 Environme ntal Earth Science.

BELOW IS THE SUPPORTING DOCUMENT ENTITLED POTENTIAL RISKS TO FRESH

- WATERRESOURCES 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

rela ted 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 ofGeosciences, 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; carb onate
dissolution; water contamination; groundwater monitoring

1. IntroductionCapture 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 poin t- 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 drinking water supply. Potential CO2 storag e 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 stu dy
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 CO 2 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 ongroundwater 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 199 5;

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 condi tions 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 fo r 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 loc ated 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 co nditions. 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, su ch 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 toundesirable levels. Elevated Pb and As concentrations as a result of
desorp tion/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 consequence s 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 reac tion. 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]. Unco nsolidated
samples were disaggregated by hand, and cemented samples were disaggregated
using a rock hammer.Using natural rock samples allows for a realistic prediction of reactions when
CO2 comes in contact with aquifer rocks. Unlike synthetic rock s amples, 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 th at
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

co ncentrations. 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 whil e 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 reactio n 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 Cranfi eld 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

e xperiment, a blank run was performed under the same conditions, but without arock 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 fil ter 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 -M S. 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 interval s 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. Achievabl e 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.3. Resul ts

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 Rea ctors 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 reacte d 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 pore filling, pore

- lining, and grain

- coating habits. Kaolinite is present in Samp les 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/precipita tion 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

hol es 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 surfaces the only SEM evidence to suggest clay precipitation during the experiment.

3.2. Water chemistryMeasured ion concentrations of each reactor were subtracted using counterpart

measurements of the blank reactor. Such subtraction reduces contamination
effects of the system, a nd 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,

showe d 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, C u, 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

conce ntrations 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 b y 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 introduct ion 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 i n 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.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 co nditions.
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 o f 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 th ese 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 de cline 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 fieldcondi tions. 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 t he 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 ab ove 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 de crease in cation release rate
demonstrates that dissolution rate of dolomite is linearly dependent on pH. pH dependent dissolution of carbonate minerals was also discussed in an injection study in basaltic rocks by Matter and Takahachi (2007). Laborato ry 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

in creased, 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 elevationsof 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 mine ral 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

C a, 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 multi sources 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 resul ted 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(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 l arger increases in K than samples without it (Reactors E and I) (Table 1; Fig. 2 [pp.

25, 32

- 33 of pdf), suggesting that K feldspar 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 wate r. 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 mi ght 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 fluct uated
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 th esystem, 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 star ted 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 p H 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 releas e 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 Z n, 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 a quifer, 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 mainl y 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 f ully 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.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 muc h 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 pre CO2 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

deterioratio n 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 minera ls 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

b e 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 rock water reaction. Risk assessment and monitoring strategies ought to therefore be
based on laboratory rock

- water reac tion 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 r eaction 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 aquiferto characterize it adequately. The study was also limite d 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 planne d 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 mobi lization 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]). Typ e 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 su ggest 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 groundwater quality 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 level s (Fig. 2; Table 2). This category

includes Fe, Al, Mo, U, V, As, Cr, Cs, Rb, Ni, and Cu.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 af fected 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

sour ces 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 b e 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 l eakage 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 wou ld 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 I I (unstable), according to their differentconcentration 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)

occur s 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 surfac e. 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 c lay 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 Wa ter 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 GFig. 4 Cation release rates as a function of p H 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

- HQ OW- 2008

- 0390

- 0387.pdf

Figure 1a - page 27 of pdf

Figure 1b - page 28 of pdf

Figure 1c - pa ge 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 pdfFigure 4 - page 35 of pdf

Figure 5 - page 36 of pdf

Figure 6 - page 37 of pdf

To download Supplementary Material: Tabl e 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 rulemakin g docket.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Steve Crookshank

Comm enter 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 SA CROCoilfield 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:

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Notes:

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

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 lesscostly 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:

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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 p roject
developers.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 addre ss storage capacity concerns while assuring that appropriate
requirements are in place to protect USDWs from endangerment.

EPA Team Member:

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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 specifical ly 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 arelikely to drive early CCS projects. For example, the initial commercial

- scale
CCS projec ts 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 protec ts 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 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 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 cat egorically 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 post

injection site care at all sites selected f or GS.

EPA Team Member:

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Notes:

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

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

EPA Comment Code: 3100 3.1. Comments on C oncerns About Injection Depth for Class VI Wells

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: 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

cl ass. 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 deter mining site suitability for GS and ensuring USDW protection from endangerment.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: John Borkovich
Commenter Organization: California State Water Resources Control Board (SWRCB)

EPA Letter ID: 0339

EPA Comment ID: 28010

O ther 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 t o 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 fluidmigration. Fluid compressibility a nd 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 post

injection site care wi ll 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 corre ctive 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:

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Date Uploaded: 16

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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 b etween 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 confiningzones 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, monito ring, 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: American P etroleum 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 t o 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 ordistance from USDWs.

Individual Response: EPA agrees that suitable co nfining 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.

Ow ners 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 requir ements 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:

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Date Uploaded: 16

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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 hasoccurred 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 protecti on 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

an alogous 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 f inal
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 limita tions 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 abo ve 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 waiv er 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 Clas s 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:

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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.- 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:
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No tes:

______________________________________________________________________________________

____________________________________________________ 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, 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 fr om 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 conditio ns 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

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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 he lp, 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 play s a role but is not always determinative.

Individual Response: 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.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 USD Ws, 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

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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, 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

ve rtical 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 whichowners and operators can seek a waiver of the Class VI injection depth requirement s.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees

Commenter Or ganization: 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 scen arios, 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 suffi cient containment.

Individual Response: 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.

However, EPA acknowledges that there are situations where injection into non

- USDW formationsabove the lowermost USDW can be performed in a manner that protects USDWs, as long as
appropri ate 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Comment ID: 27971

Comment: Comment No. 28

Page 448 09

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 endange r 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.

Individu al Response: 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.

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

res ponses to comments on the proposed GS rule.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Comm enter 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, 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.

However, EPA acknowledges that there are situations where injection into non

- USDW formationsabove the lowermost USDW can be per formed 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

informa tion 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

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Notes:

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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 USD W 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 afundamental 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 reducin g 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 r eport) 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

abou t public water supplies in the AoR.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Na me: John V. Corra
Commenter Organization: Wyoming Department of Environmental Quality (WDEQ)

EPA Letter ID: 0386

EPA Comment ID: 28155

Comment: Additionally, GS opportunities in Wyomin g 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 protect s 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 requirement s 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 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 aqu ifer
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 substantia l 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:

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Date Uploaded: 16

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Notes:

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

EPA Comment Code: 3120 3.1.2. Allowing GS in All Form ation Types

EPA Team Member:

Draft Status:
Date Uploaded: July 16, 2009Notes:

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 Re sponse: 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 pro cess 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 si te 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 suppl ies in the AoR.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________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 :

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Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environm ental 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 i n 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, saltcaverns 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 shallo w 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, monitori ng, and post

- injection site care pursuant to the GS rule
requirements will ensure USDW protection.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

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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 C ode:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. Sims Commenter Organization: Western Business Roundtable EPA Le tter ID: 0357 EPA Comment ID: 28224Comment:

- 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 disti nctions 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

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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 w ith 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 commerci al scale 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 in jection depth limitations across the board is unnecessary and
counterproductive, particularly when the EOR context is considered. EOR projectsare 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.

Indivi dual 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 establishe s 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

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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 projectsstoring 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 projec t 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 applicatio n 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:

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Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara PriestCommenter 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
highe r 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

wh ere 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:

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Date Uploaded: 16

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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 op erations indicate that these well classeswarrant 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. 44 810

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:

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Date Uploaded: 16

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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, large scale injection, this alternative allows Class VI injection depth considerations

to be tailored for GS.

Carbon Sequestration Council CommentsWithin the past year, there have been several papers that have dem onstrated 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." Th e 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 f uture 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,

200 8. 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.utex as.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
analog y 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 according ly. 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 th at 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:

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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 CommentsThe 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 C FR 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 hydro carbon 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 subje ct
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 letter s 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 forwhich 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:

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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 pr ocess. 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 a quifer 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 U SDW 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 purp ose 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 waiv ers 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 cla rifies 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:

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Date Uploaded: 01

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Notes:

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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 Comment er 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 approac h 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 regul atory hurdlesto 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
develop ment 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 necess ary, 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 waive r 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 -s pecific assessment of injection depth for GSprojects; 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Paque
Commenter Organization: Ground Water Pr otection 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 aquife r 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.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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: B. Peter McGrail
Commenter Org anization: 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

dra ft 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

domesti c 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 endors e 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]Finally, new re servoir 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 Geol ogical 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 ad ditional 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Rebecca Thingelstad
Commenter Organi zation: 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 a bout the waiver process as currently designed. First, the EPA has notdemonstrated 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 propose d 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 i njection 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:

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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.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 de pths. 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 ag ency 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

contai ning 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 pre clude 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 pr ocess 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 bou ndary 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:

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Notes:______________________________________________________________________________________

____________________________________________________ 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 warra nted. 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 ex pansions
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 ex pansion 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

t he applicable State under Part 147.

EPA Team Member:Draft Status:
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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Na me: 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 encourag e 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.

I ndividual 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. Commenter s 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 b e 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 b elieves that Agency involvement in the waiver decision process will contribute to nationalconsistency in waiver issuance.

EPA Team Member:

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Notes:

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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 site specific demonstration is made that USDW will be prote cted

- > 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 a bove 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 comment er'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 abo ve the lowermost USDW can be performed in a manner that protects USDWs.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 int egrity 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 determinatio ns 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 approa ch: 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 int o 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 a lternative 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.[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

re quire 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 protectio n 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 contex t. 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 assessmentIndividual Response: 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

formati ons 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, si te

- 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 be st 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 addit ional
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

No tes:

______________________________________________________________________________________

____________________________________________________ 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 prop osal 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,acros s- 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 en hanced 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

propos al 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 fin al 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 t o 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 ass essment 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: 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 site spec ific 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 Cla ss 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 a bout 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 nee ds.

EPA Team Member:

Draft Status:
Date Uploaded: 16

- AUG

- 10

Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Mark Bohrer
Commenter Organ ization: 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

safel y 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

m ay 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 sit uations 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 r equirements.

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 additio nal
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 injectionthat 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 pr ovide 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 Co mment 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 com peting 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 allow ing
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 provideadditional 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 requ irements; 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

drink ing 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 Fe d. 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 requir ements. 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 uponmaking 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
protecti on 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 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. 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 supp ly 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 suggest ion 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 orrendering 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

wit h 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 manne r 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
througho ut the country, allowing for maximization of safe CO2 storage capacity

nationwide.

Individual Response: EPA acknowledges the commenter's support of the waiver approach and site

specific flexibility in regulatory development and permitting as described i n 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 proces s 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
injectio n 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. StineCommenter 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 F ed. 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. a t 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. 7 4
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 requireme nts 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 acknow ledges 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 -U SDW
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 GSprojects; 3) accommodat es 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 aquife r 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 suffi cient 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 pote ntial CO2 GS sites throughout the country, allowing formaximization of safe CO2 storage capacity nationwide.

Individual Response: EPA acknowledges the commenter's support of the waiver approach and site

specific flexibility in regulatory development an d 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 impos ed 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 b etween 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

Not es:

______________________________________________________________________________________

____________________________________________________ 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 saltformation s 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 site

specific flexibility in regula tory 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 capacit y 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 -U SDWs 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 throug h 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 technol ogies 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. However, EPA also believes that additional considerations are necessary when
permi tting 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:

Dra ft 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 originalproposal 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 requirem ents 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 protec tion 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 commente r'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 abov e 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

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- 10

Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Pa ul 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 wo uld 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 contami nation. 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

maximiza tion of safe CO2 storage capacity nationwide.

Individual Response: 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. Th e 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 se ek 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 forGS 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 availab ility 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 s upports 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 protecti on 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 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 lowerm ost 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 ensurethat high quality water remains available in sufficient quantities to supply drin king water needs.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Michael J. Mil ler
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

ag ree 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
regul atory 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.

T he 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

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Joh n A. Gulvas
Commenter Organization: Consumers Energy (CE)EPA Letter ID: 0356

EPA Comment ID: 28088

Comment: CE also supports EPA’s suggestion to adopt a flexible waiver process to all ow 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 f ormation 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 pro posal 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 USD W 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

max imization of safe CO2 storage capacity nationwide.

Individual Response: 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

Commen t. 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 c an 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 f or 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

demonstrat ed 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 av ailability and the need to ensurethat 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 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. 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 ne eds.

EPA Team Member:

Draft Status:
Date Uploaded: 28

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Verne Shortell

Commenter O rganization: NRG Energy, Inc.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 an d 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 Fe d. 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 inj ection 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 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 V I 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 assessm ent 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 ensu rethat 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 lowerm ost
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 Respo nse: 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 d ecisions) 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 betw een 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.

For additional information on transitioning Class II wells for GS, see the preamble to the final rule and
the responses to comments on t he proposed GS rule.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Michael Moo re 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 ot hers, 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

p otential 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 wa iver 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 site

specific flexibility in regulatory devel opment and permitting as described in the NODA and Request for
Comment. The Agency acknowledges that there are some situations where injection into non

- USDWformations 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 bel ieves 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 assessmen t 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 begin ning 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 USDW s. 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.Individual Response: 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. EPA agrees that a flexible, site

- specific approach to waiver

dete rminations (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 ve ry 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 consi deration of new
information and data from comments received, and its resulting proposal toconsider 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 unneces sary 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 deve lopers.
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 t he GS program.

Individual Response: 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 ther e 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 inj ection 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 waiv er 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

addres sing 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Paque
Commenter Organization: G round 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 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 V I injection depth requirements. Please see EPA's specific responses below.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Smith
Commenter Organization: Questar Exploration & Production Company

EPA Letter ID: 0374

EPA Comment ID: 28118

Comment: Questar apprec iates 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) ProgramIndividual Response: 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 acknow ledges 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

- speci fic 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 b e 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 n eed 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 fol low 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 wate r.epa.gov/type/groundwater/uic/wells_sequestration.cfm.

EPA Team Member:

Draft Status:
Date Uploaded: 23

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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 Allowe d 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 belowthe 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

t hat 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 site

specific flexibility in regulatory development and permittin g 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 esta blishes 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 p roposed 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 form ations 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)EPA Letter I D: 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 site specific assessment and allows for injection into appropriate formation types,
based on quality of a particular geologic basin.

NOGCC houses what we believe is the mo st 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 geologica l 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 fa ctors.

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 supp ort 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 lo wermost 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 add ress the challenges associated with GS and injection
that will be conducted under the waiver approach, e.g., to inject through over

- pressurized reservoirs.However, EPA also believes that additional considerations are necessary when permitting such wells t o 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 requir ements 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, th e 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:

Draf t 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 proj ect in Wyoming, which has a USDW belowthe 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 USD Ws 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

drillin g 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 site

spec ific 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 injectio n 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 dril ling 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 pe rmitting 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 Seq uestration 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) requireme nts.
These States suggest that GS should be allowed in certain areas if a site specific demonstration can be made that USDWs will be protected.

Carbon Sequestration Council Comments

We support the provision to allow CO2 injection into formations abo ve 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

demonstrati on 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 site

specific flexibility in regulatory development and pe rmitting as described in the NODA and Request forComment. 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 b y 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 betwe en 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 resp onds 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

u nderground 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 site

specif ic 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 bedemonstrated 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:

D raft 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 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 owne rs 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 b e 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 post

injection site care at all sites selected for GS.

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: 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 haz ardous
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 accou nt
for circumstances in which there are deep USDW.

Eliminating the default prohibition and making siting determinations on a case by

- 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 abaseline 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 agree s 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

re quirements. 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 Charac terization

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 thre ats
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 prohibi tion on use of potential receiving formations above the
lowermost USDW, even where regulatory provisions for a waiver are available, isunnecessary. 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

clarifi es 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 submit ted

Individual Response: 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 dept h 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 bedemonstrated that USDWs will be protected; and 5) respond s 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 qua lity 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 petroleum bearing deposits above, as well as adjacent to USDWs in Wyoming.

Individual Response: 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 situa tions 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 req uirements. 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 dept h for GSprojects; 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 grante d 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 b y state programs with primacy.

Individual Response: 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 acknow ledges 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 proposedinjection depth requirements; 2) allows for a more site

- speci fic 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 b e 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 n eed 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 g eologic 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, Te rritories, 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 shallowgas 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 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. 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 respon ds 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 th e challenges associated with GS
and injection that will be conducted under the waiver approach, e.g., to inject through over

pressurized 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 byIndividual 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

Note s:

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

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

EPA Comment Code: 3220 3.2.2. Comments in Opposition to the Approach

EPA Team Member:

Draft Status:
Date Uplo aded: 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 USD W".

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 pressurewithout 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Anonymous9
Commenter Organization:

EPA Letter ID: 0335

EPA Comment ID: 28214

Comment: invested in renewables and e fficiency 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 Resp onse: 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 reso urces 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 non

USDW formations above the lowermost USDW can be performed in a manner that protects USDWs.

Th e 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 tomonitor 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

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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 full y 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 infor mation 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 wat er supplies in the area and all USDWs are protected.

EPA Team Member:

Draft Status:
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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: 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?"

I njecting 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 liq uid 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 su bsequent 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 surf ace 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 post

injection site care will al low 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 t his 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

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Notes:______________________________________________________________________________________

____________________________________________________ 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 benefit effect 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 c omments 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 p erformed 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

- specif ic 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:
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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: William E. FreemanCommenter 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 lo west 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 §1 46.95 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

t he 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 da ta, 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

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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][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,

St anford 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

c ontaminated 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 altern ative
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 pa rticular, 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.pdfConclusion
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 feasi bility 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 cau tion 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 t his 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 ackn owledges 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

additio nal 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 a nd the post

- injection site care
period.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

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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 W ater (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 USDW s 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.- GS in Oregon could be propo sed 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 wo uld 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 rulema king 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 t he 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 establishe s 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 oper ator 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
requir ements 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 adoptGS 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 Me mber:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis
Commenter Organization: Ameri can 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 chall enging 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 d efinition 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 stat e 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 non traditional 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.Individual Response: EPA agrees that USDW protection is the highest priority and clarifies that the

pu rpose 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 au thority 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,

an d 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 informati on 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 progr am 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

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

EPA Team Member:

Draft Status:
Date Uploaded: 28

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis
Commenter Organization: American Water Works Association (AWWA)

EPA Letter ID: 0369

EPA Comment ID: 27940

Comment: WAIVER PROCESS FOR INJEC TION 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. Effortsto 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 monitor ing 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 simi lar 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
inj ection 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 ar e 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 areartificial penetrations, it appears that they would be plugged, makin g 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 unclea r 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 progr am.

- 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 benefi cial 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 Progr am 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

lowermo st 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 -s pecific 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 confinem ent 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 Directo r 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 th e requirements, §146.95(d) requiresthe 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 U IC 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 m aintaining 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 constructe d, 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

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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 thatpr oject 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 issue s, 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 actio ns to protect USDWs from
endangerment.

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______________________________________________________________________________________

____________________________________________________ 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 requiremen ts, 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 do es 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.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 p erformed 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, i n 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 cons truction 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.

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____________________________________________________ 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

concerni ng 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 age ncy 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 prote ct USDWs from endangerment. Based on anevaluation 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 inj ection
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 re quirements 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,

testi ng, 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.

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______________________________________________________________________________________

____________________________________________________ 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 utmostconcern. 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 provi de:

• 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 a ffected 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 consideration s 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.

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____________________________________________________ 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 positionprohib iting 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". Furt hermore, 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 n on

- 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 ad ditional information when permitting such wells to ensure protection of all USDWs.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe Hei
Commenter Organization: Association of Metropolitan Water Agencies (AMWA)

EPA Letter ID: 0383

EPA Comment ID: 28104C omment: 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 a nd 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 P rogram’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 con cerns 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

fo r 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 sit e 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 protect s

USDWs.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe Hei

Commen ter 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 ot her 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 re commends 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 a rea 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 curre ntly 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.Individual Response: As described above, EPA disagrees that adoption of the waiver p rocess 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.

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______________________________________________________________________________________

____________________________________________________ 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

lowermos t 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 fort h 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,

w ith the creation of clear and appropriate parameters, would also provide more
transparency and predictability than the waiver process to future applicants.Individual Response: EPA agrees that all decisions regarding waivers (and all aspects of GS proje ct 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.

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

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

EPA Comment Code: 3230 3.2.3. Comments that Additional Submissions are Needed (seeking
comment)

EPA Team Member:

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Comment Summary:

Response to Comment Code:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis Commenter Organizati on: 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 baselinewater quality data for the potentially impacted USDWs to allow for any
degradation in water quality to be measured from the baseline condition s 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 sho uld 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 fou r (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 acc ess 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

- spe cific 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.Many of these additional requirements specifically address water resources and the type s 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, site

specific 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 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 acc ess 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 fina l 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 remedia l response plan, and a demonstration of financial responsibility as specified in §146.95(b)(1)(iv).

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______________________________________________________________________________________

____________________________________________________ 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 injec tion 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 orpractical reasons.

Individual Resp onse: 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.

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______________________________________________________________________________________

____________________________________________________ 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.Individual Response: EPA agrees that protecting drinking wat er 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.

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______________________________________________________________________________________

____________________________________________________ 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 con sider 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 ot her 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 permi t 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 bisectpressurized 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 inj ection 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 tha t 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 th e 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.

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______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe HeiCommenter Organization: Association of Metropolitan Water Agencies (AMWA)

EPA Letter ID: 0383

EPA Comment ID: 28106

Comment: Amwa str ongly 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

comp leted 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 proc ess 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 t o 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 useand 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 owne r 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 he aring; §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 availabil ity 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 beoptional for adoption by state programs with primacy.

Individual Response: EPA agrees that protecting drinking water resources is vital and is the purpo se 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,

line s 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.Individual Res ponse: 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 Agen cy 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 in jection
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

Direct or when permitting such wells to ensure protection of all USDWs.

EPA Team Member:

Draft Status:
Date Uploaded: 16

- AUG

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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 requ ired 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 atransparent 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 inj ection 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 appl ication) 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 re dundant 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 t he
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 applic ation,
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/well s_sequestration.cfm.

EPA Team Member:

Draft Status:
Date Uploaded: 23

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Paul R. Pik eCommenter 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 applic ants, 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 waive r 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
(t he 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 (fr om 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 comple mentary 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 is sues, 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 considerationsthat may apply to projects that have been issued waivers. This guidance will be available on EPA’s
website at water.epa.gov/type/gr oundwater/uic/wells_sequestration.cfm.

EPA Team Member:

Draft Status:
Date Uploaded: 23

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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 waiv er 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 obtai n 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 dis crete (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 applicatio n.

EPA Team Member:

Draft Status:
Date Uploaded: 16

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- DoranCommen ter 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 applicati on 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 ent ire 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 f or 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,

oper ation, 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: John V. Corra
Commenter Organization: Wyoming Department of Environmental Quality (WDEQ)

EPA Letter ID: 0386

EPA Comment I D: 28156Comment: 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 con fined 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. Thi s 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 Clas s 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 requireme nts 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)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; addit ional
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, hyd rocarbon, 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 th e 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 wa ter
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 requir ements 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

Commen t: 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 theseformations, 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

A nother 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 th e 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 t here 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

Comme nt: 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 desc ription of the types of additional information that may be soughtfrom 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 appro priately 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
guid ance 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 issu ed 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

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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 technolog ies 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 experien ce 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 rulerequires 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 specif ied 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 demonst ration
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 anappropriate 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 c omparison 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 i s 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 co nstruction, 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: R obert 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 Submi t 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

Concre te 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

- 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 perspecti ves.

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 pr ovide 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

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0 382

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 alter native 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.

In dividual 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 res ponsibility 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 require d 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: 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 regard ing 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe Hei
Commenter Organization: Association of Metropolitan Water Agencies (AMWA)EPA Letter ID: 0383

EPA Comment I D: 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. Further more, 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 inj ection 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 respon se 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.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 fed eral
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:

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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.

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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 AngielskiCommenter Organization: Coal Utilization Research Cou ncil (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 submit tal 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 c hemical
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 b uoyant 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 inje ction 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 pres ence 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 constructio n, 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 a nd 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

rea ctions 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:Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: John Borkovich
Commenter Organization: California State Water Resources Control Board (SWRCB)

EPA Letter ID: 0339

EPA Comment ID: 28011

Comment: C. SWRC B 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 requi red 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, i mpermeable 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 oper ators 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 a nd 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

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Notes:______________________________________________________________________________________

____________________________________________________ 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 ex clude 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 exc ellent
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 rul e and the responses to comments on the proposed GS rule.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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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 charac terization of regional fracture properties and a
demonstration that such fractures will not interfere with injection, serve as
conduits, or endanger USDWs."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 m ay 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 se rve 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 G S 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

- spec ific 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

wher e 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. F or 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Michael J. MillerCommenter Organization: Electric Power Research Institute (EPRI)

EPA Letter ID: 035 5

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 p roject 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 R esponse: 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

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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.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

e ndangerment 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 m odify 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Comme nter 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

restricti ons 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 ow ners or operators of proposed
GS sites must provide extensive geologic information about the site, including its seismic history per§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 maintai ned through the life of the GS project.

EPA Team Member:

Draft Status:
Date Uploaded: 16

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commente r 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 r egarding a matrix dissolution requirement
should at least be heavily caveated but preferentially removed in any future
drafts of these regulations.Individual Response: EPA clarifies that the GS regulation requires all owners or operators to submit

inf ormation 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 §146.8 2(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

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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

thro ugh 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 theproposed injection zone is reasonable and technica lly 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 Recommenda tion 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

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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)A characterization of regional fracture properties and a demonstration that such
fractures will not interfere with injection, serv e 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 verti cal 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 injecti on 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 depthrequirements would result in impractical or technically infeasible well construction, and whe re USDW
protection is demonstrated and maintained through the life of the GS project.

EPA Team Member:

Draft Status:
Date Uploaded: 16

- AUG

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organization: Edison Electric Institute (EEI)

EPA Letter ID: 0384

EPA Comment ID: 28123

Comment: Fu ndamentally, 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 proje ct.
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 charac terization, 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 Upload ed: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organization: Edison Electric Institute (EEI)

EPA Letter ID: 0384

EPA Comment ID: 28130Other EPA Comment Codes and Descriptions: 3210 3.2.1. Comments Generally in Support of the
Approach

Comment: Fundamentally, proper site selec tion 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 t he
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)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 t he 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

managem ent 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 Agen cy 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 consider ation the presence of USDWs
above and below the injection zone.

EPA Team Member:

Draft Status:
Date Uploaded: 23

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organization: Spectra Energy Corp

EPA Letter ID: 0385

EPA Comment ID: 28574

Comment: require a separate application pro cess with redundant data submittal. Second,
the waiver applications should not require the operator to complete a basin level study but rather demonstrate no impact on existing adjacent subsurface
operations such as gas storage, production and geologic sequestration. Third,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

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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 tha t 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 wellrequirements and thus would not serve as conduits to conta minate 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

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Notes: This comment contains text from lines 265 to 276, which is an excerpt from the previous

section, lines 226 to 286. T his comment appears twice in this report, once for each set of line

numbers.

______________________________________________________________________________________

____________________________________________________ Commenter Name: Robert Voorhees

Comme nter 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 penetration s can be appropriately plugged during the permitting phase.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 constr ucted 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 Wellb ore 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

act ion 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 requirem ents 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 Upl oaded: 16

- AUG

- 10

Notes:

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

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

EPA Comment Code: 3330 3.3.3. Emergency and Remedial Response

EPA Team Member:

Draft Sta tus:
Date Uploaded: July 16, 2009

Notes:

Comment Summary:

Response to Comment Code:

### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commen ter 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 N ODA

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 Cla ss 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 confusi ng 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 outs et 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 injectionzone. EPA anticipates that issuance of waivers will be limited to circumstances where there are deep

U SDWs 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 r ule, 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

- 10Notes: 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.

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

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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 A gency (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
responsibil ity," 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 potentialcontamination 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 h as 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 financia l 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 NationalLaborat ory

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. T he 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 t hat 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

sec uring 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 o perators 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 pr esence 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

techni cally 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 §146.8 5 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 beavailable 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 comment s, 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 unnecessari ly 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 o r 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 t roubled 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 o r 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 t his 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.Individual Response: The r equirements 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 sit e 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.

EP A 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: Con cerning 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 t o 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 d emonstration 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

pro posed 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 capabilityto 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 us es? 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 respons e 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 becom es 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 an d 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 belo w 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: Comme nt No. 47Page 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

maintaini ng 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 t he
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 Cou ncil

EPA Letter ID: 0382

EPA Comment ID: 27994
Other EPA Comment Codes and Descriptions: 3300 3.3. Comments on Specific Elements of the
Waiver ApproachComment: Comment No. 52

Page 4 4811

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 reg ular 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 a ll 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 clar ifies 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 Mem ber:

Draft Status:
Date Uploaded: 05

- SEP

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe Hei
Commenter Organization: Asso ciation of Metropolitan Water Agencies (AMWA)EPA Letter ID: 0383

EPA Comment ID: 28110

Comment: - Long

- term financial responsibility (> 50 years) must be assigned to ensure the

viabil ity 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
requirem ents 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 instr ument 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 circumsta nces. 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 si te 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 oper ator 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 ap propriate 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 previoussection, lines 154 to 166. This comment appears twice in this report, once for each set of li ne

numbers.

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EPA Comment Code: 3350 3.3.5. Requirement to Submit Waiver Application to UIC and PWSS
Program Director s

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 o f 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

i nto non

- USDW formations above the lowermost USDW is being considered. Due to the unique natureof the injection depth waiver process and in an effort to ensure national consistency and application of the requirements, the requirement at §146.95(d) indicate s 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 appr opriate 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 individ ual 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 di rector 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 appea r 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 recommen dations. EPA clarifies thatthe 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 ab ove 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 Admini strator 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 Tea m Member:

Draft Status:
Date Uploaded: 28

- SEP

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis
Commenter Organization: A merican 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 Pri macy 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 in cludes 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 aUIC 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 writte n 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,
publi c 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

- stat e 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 hav e 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:

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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 suc h 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 P WSS
agencies would need to hire additional staff and acquire appropriate trainingfor 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 PW SS 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

governmen t 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 requiremen t 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 re commendations. 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 formati ons 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 ofthe 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 T eam Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Paque
Commenter Organization: Gr ound 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 proce ss:

1. The authority for granting a waiver should rest solely with the state UICprimacy agency.

Individual Response: EPA clarifies that the final determination regarding waiver issuance will be
made by the Director, following evaluation of all site -s pecific 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 form ations 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 mus t 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 concurr ence 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

Director s 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 whe n evaluating a waiver application.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Nam e: 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 necessaryand appropriate to ensure that water system concerns are considered when eva luating 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 thi s 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:

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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 spec ified 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:

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Notes:______________________________________________________________________________________

____________________________________________________ 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 prim acy 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 sy stem 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

- specif ic 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 th e waiver process if this is deemed too burdensome.

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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 authori ty 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

v eto 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 add ition, 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:

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Notes:

______________________________________________________________________________________

____________________________________________________Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

EPA Comm ent 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 suitabl e 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 containme nt
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 abov e 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 Dire ctors would encroach upon the prerogatives of the states under the UIC
primacy program in violation of the UIC regulations; and division of authoritybetween 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 Direc tor 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

D irectors 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 conside red 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 t o 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 w aiver 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:

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Notes:

______________________________________________________________________________________

____________________________________________________Commenter Name: Robert Voorhees
Commenter Organization: Carbon Sequestration Council

EPA Letter ID: 0382

E PA 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 makin g 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

includ es 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 nece ssary 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 beingconsidered. 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:

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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, poten tial 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 consider ed
within the context of the SDWA endangerment standard for protecting USDWs.

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 th e Safe
Drinking Water Act.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Rober t 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 HearingComm ent: 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 C lass 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 Director s 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

- con currence 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organization: Edison Electric Institute (EEI)

EPA Letter ID: 0384

EPA Comment ID: 28132Comment: 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
appli cations 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

w ith 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 concer ns 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 wai ver 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: John V. Corra
Commenter Organiz ation: 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

Di rector 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,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 und er 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 kn ow, 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 report s 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 uncertai nty 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 waiv er 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 loc al 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 potenti ally 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 beprovided to those entities. In addition, US EPA may wish to cons ider 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 recommendat ions.

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 abo ve 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 addit ional 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

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- 10

Notes :

______________________________________________________________________________________

____________________________________________________ Commenter Name: James Taft
Commenter Organization: Association of State Drinking Water Administrators (ASDWA)

E PA Letter ID: 0392

EPA Comment ID: 28757Comment: In particular, ASDWA is offering comments on the portion of the NODA proposal
suggesting that state drinking water program directors pl ay 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 cons ulted 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

stat e 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 agencie s 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 necessar y 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 dis closure
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 ofthe 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 th e 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 protecti on. 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 o f the Safe
Drinking Water Act.

EPA Team Member:

Draft Status:
Date Uploaded: 18

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Notes:

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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)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

w

aiver 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 w aiver 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 w aiver 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 th is 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, Trib e, 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 dep th 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 p rojects 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: American Petroleum Institute (API)

EPA Letter ID: 0350

EPA Co mment 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 fina l 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 applicatio n 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 discr ete (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 recei ves 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 processrequirements.

EPA Team Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower
Commenter Organization: American Petroleum Institute (API)

EPA Letter ID: 0350

EPA Comment ID: 28052

Comment: API supports the wa iver 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 tha t 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

d epth 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 -s pecific 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 balanceUSDW protection and disclosure of PWSS information with the GS permit application process
requirements.

EPA Team Me mber:

Draft Status:
Date Uploaded: 05

- OCT

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mike Paque
Commenter Organization: Ground W ater 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 exe mptions.

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 app lication 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 pote ntial 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 c an 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 a nd
issuing the Class VI permit.

In addition, the public notification process for the waiver must occur concurrently with the UIC permitnotification to ensure that all necessary information is disclosed to the public for notice and comment
and that the pu blic 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

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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

EP A 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 shoul d 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 applic ation, 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 theproposed 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 supp lemental 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 wasteinjection. 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 comp letely 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

USD W 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 du plicative 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 appli cation, 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 su pplemental 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 appli cation 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 applicationrequirements. 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. E PA 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

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- 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 i n 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, noparticular reason why these criteria could not be specified and considered as
part of the regular permit ap plication 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

notific ation 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 f or 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 T eam Member:

Draft Status:
Date Uploaded: 16

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organ ization: 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 re quired 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 hasadeq uate 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
appl ication 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
compl ementary 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 a ddition, 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 pe rmitted, 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.

EP A Team Member:

Draft Status:
Date Uploaded: 16

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- DoranCommenter Or ganization: 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 ensuri ng 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 waiver s 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 repo rt, 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
applicati on 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 redunda nt 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 St atus:
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: 28324

Comment: Class VI UIC Program. EPA should integrate the waiver process into the normal

pe rmit 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, owner s 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 inje ction 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 noti ced. 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:

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EPA Comment Code: 3370 3.3.7. Notice and Heari ng

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 Desc riptions: 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 he aring 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 a gency. 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 consultat ion 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.

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____________________________________________________ Commenter Name: Diane VanDe Hei
Commenter Organization: Associat ion 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 cur rent 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 i n 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 isdisclosed 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.

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____________________________________________________ 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 inf ormed 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

sparse ly 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, und er 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 applicat ions, but that the Director be provided discretion to holdpublic 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 U IC 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.

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____________________________________________________ Commenter Name: Kristin Henry
Commenter Organization: Sierra Club, Environmental Law Program

EPA Letter ID: 0388

EPA Comment ID: 28303

Comment: Secon d, 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 succ ess 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, CCStechnologies 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 Technol ogy 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 ent ities 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 t hat 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 dire ctor,
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 notificationassociated with GS permitting, see the pream ble to the final rule and the responses to comments on
the proposed GS rule.

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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 in jection 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 bei ng 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 withinjection 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

- 039 0- 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 prot ective
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 t he 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. Sali ne 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 warr ants tailored requirements to address the unique
challenges and risks relative to injection below the lowermost USDW. For example, there is a risk ofdownward 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.

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______________________________________________________________________________________

____________________________________________________ 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 aredesigned 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.

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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

relation ships 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 Tri bes 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 commentersasked EPA to requ ire 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 Dir ectors 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.

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____________________________________________________ Commenter Name: Steve Nightingale
Commenter Organization: Illinois Environmental Protection Agency (IEPA)

EPA Letter ID: 0333

EPA Comment ID: 28201

Other EPA Comment Codes and Des criptions: 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 eva luate 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 thecurrent UIC programs.

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of
individual UIC programs. Therefore, States, Territor ies, 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 prote ction 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 fol low 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.

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____________________________________________________ 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.Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of
individual UIC programs. Therefore, States, Territories, a nd 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 t o 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.

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____________________________________________________ Commenter Name: John M. McManus
Commenter Organization: American Electric Power Service Corporation (AEP)

EPA Letter ID: 0345

EPA Comment ID: 27881

Comment: While AEP suppor ts 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 flexib le 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 tomake 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 de pth 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) an d 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

ne cessary.

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____________________________________________________ Commenter Name: Barbara A. Walz

Commen ter 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

p rerogative 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.

In dividual 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 wellsare 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

- spe cific 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. UI C 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.

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____________________________________________________ Commenter Name: James F. Stine
Commenter Organization: National Rural Electric Cooperative As sociation

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 th e 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;

beca use this experience with and information regarding this technology is
growing rapidly, it is prudent to structure a regulatory framework that isflexible 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 geolog ic 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 th at 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 amoun t and types of information and appropriate documentation
are being collected, and to determine if modifications to the requirements are appropriate or

necessary.

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______________________________________________________________________________________

____________________________________________________ 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 wouldstill 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 rem ains 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 Respons e: 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 Direct ors 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 developi ng. 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

determi ne 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:

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No tes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Claire M. Olson
Commenter Organization: Basin Electric Power Cooperative (Basin Electric)

EP A Letter ID: 0351

EPA Comment ID: 28056Comment: While Basin Electric supports the flexible injection depth waiver proposal
described above, we urge EPA to consider requiring the inclus ion 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 thi s 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 adopt ing 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 ty pes of information and appropriate documentation
are being collected, and to determine if modifications to the requirements are appropriate or

necessary.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Paul R. PikeCommenter 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 wou ld
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, Stat es, 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 comm enters
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 m aximum 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 re view 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 deter mine if modifications to the requirements are appropriate or

necessary.

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: John A. Gulvas
Commenter Organization: Consumers Energy (CE)

EPA Letter ID: 0356

EPA Comment ID: 28089

Comment: While CE supports the flexible i njection 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 n ot
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 believe s 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 represe nts
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:
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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. Sims
Commenter Organization: Wes tern 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 de pths 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 site

specific flexibility in regulatory development and pe rmitting 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
protectio n 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.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.

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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 requi re 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 Federalrequirements. 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 p rotective.

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

neces sary.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jeanne Herb
Commenter Org anization: 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 w aiver 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,

an d 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 specificbasis.

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 provi de 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

mi nimum 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 M ember:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott L. Davis
Commenter Organization: Ari zona 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, Territor ies, 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 aboutwhether 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 prote ction 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:

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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

measu res 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 signi ficant 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. Althou gh 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 fl exibility for individual program Directors to determine theappropriateness 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 whil e 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Stan Belieu
Commenter Organization: Nebraska Oil and Gas Conservation Commission (NOGCC)

EPA Letter ID: 0378

EPA Comment ID: 2857 0

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

prop osed 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 appro ach 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.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 a nd 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:

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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. W here 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 tomake this process available to Class VI wells under their jurisdict ion. 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 approac h 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 Regio nal 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:

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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.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 a re 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:

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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 re gulatory
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

techn ical 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 wellsare 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 believe s 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 represe nts
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:

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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 requireme nts that do not allow injection above or between USDWs if they determine this to be appropriate (for conditions in theirState, 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Comme nter 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) USDW s." 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 leve l 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 decision s can contradict
science and logic and produce dangerous results for local health and welfare.
For instance, the Florida Department of Environmental Protection approved theconstruction and operation of a facility designed to inject more than 112

milli on 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 well established, Florida continued to expand its injection program. The Florida
program was supposed to prevent the migration of sewag e 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 prima cy 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 determi ne 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 app roach 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 Regi onal 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

- concur rence regarding
waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe
Drinking Water Act.

EPA Team Member:

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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: 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 Pro gram. 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 Clas s 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

appr opriateness 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 i njection 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 regar ding
waiver issuance. The Agency clarifies that these requirements are within the authority of the Safe
Drinking Water Act.

EPA Team Member:

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EPA Comment Code: 3400 3.4 Additional Information Regarding the Waiver ApproachEPA 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 Co uncil (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 injectio n 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 C lass 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 USDW s 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 Te am Member:

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Notes:______________________________________________________________________________________

____________________________________________________ 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 proce ss 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 r ule. 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 t he 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 expa nsions 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 appl ies 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Quinlan J. Shea, III
Commenter Organization: Edison Electric Institute (EEI)

EPA Lett er 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 res ource 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

und erground 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 benefi ts 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 th e 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 anyinjection depth limitations with it in mind.

Indiv idual 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 t he 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:

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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 C omments

______________________________________________________________________________________

____________________________________________________ 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 applic ability
of the proposed waiver process appears very limited. EPA's apparent intent isto 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 respec t 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 latt er 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.

In dividual 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 aq uifer 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 fo r 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 expansion s for GS should be granted in limited circumstances.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. SimsCommenter 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 th is 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
requireme nts 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

forma tions 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.

E PA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Michael Moore
Commenter Organizat ion: North American Carbon Capture and Storage Association (NACCSA)

EPA Letter ID: 0362

EPA Comment ID: 28260Comment: III. Specific Comments
a. Project Siting
The proposed regulation s 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 b ased 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 conf ining 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

perm it 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 shal low
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 t hat such injection can be performed ina manner that protects USDWs.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environmental Defense Fund (EDF)

EPA Letter ID: 0376

EPA Comment ID: 28166

Comment: B. Definitions in the NO DA

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 definit ion 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 ru le 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, monitorin g, and post

- injection site care pursuant to the GS rule requirements will ensure
USDW protection.

EPA Team Member:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environmental Defense Fund (EDF)

EPA Letter ID: 0376

EPA Comment ID: 28167

Comm ent: 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 th e 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 requi rements 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 wai vers 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., inbasalts, 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 C lass V experimental technology

well or a Class VI well will be site

- specific and depend on the nature of the project.

EPA Team Member:

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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 ev erywhere, 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 e xperience 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 seq uestration in basalts, coal seams, salt caverns
and shales. The trapping mechanisms of CO2 and/or the operational engineeringinvolved 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 wh ether 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 basal ts, 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:

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Notes:

______________________________________________________________________________________

____________________________________________________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

Fu rthermore, 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) il lustrates 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 partici pants 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.Individual Response: EPA agrees and clarifies that the GS rule does not categorical ly 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, monito ring, 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 prote cts 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:

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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 aff ords all
formations equal treatment and allows specific regions of the country the
regulatory flexibility to determine if any injection at a particular site anddepth is the appropriate approach. It will also help to manage injection in

areas where the re 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 p roposing 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 W yoming,
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 belo w 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, monit oring, 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 prot ects 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.

______________________________________________________________________________________

____________________________________________________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 widesp read 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 engineerin g 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, recognizi ng 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

expe rience 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, sect ions 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 non experimental 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 i njection 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 techno logy

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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran
Commenter Organization: Spectra Energy Corp

EPA Letter ID: 0385

EPA Comment ID: 28400

Comment: As disc ussed 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 ap plication of GS in areas such as
the Williston and Powder River Basins in Wyoming and the Dakotas, where thelowermost 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
prohib it 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

- inject ion 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kristin Henry
Commenter Organization: Sierra Club, Environmental Law Program

EPA Letter I D: 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 definitio ns.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 containi ng 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 s upercritical 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 IPC C 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 sequestrat ion projects in these formations.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 demonst ration
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 protectiv e 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 ensu re 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

- specifi c 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

§1 46.95 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kristin HenryCommenter 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 a bove, 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 p roposed 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. Therefo re, 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

o wner or operator meets the other protective requirements at §146.82 through §146.94.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 wel ls 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

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- 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 USD W 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 i n 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 than10,000 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 deep er 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 USD Ws 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mark Bohrer
Commenter Organization: North Dakota Industrial Commission (NDIC)

EPA Letter ID: 0343

EPA Comment ID: 28566

Comm ent: 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 - pr essured 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 wate r, hydrocarbon, or mineralresource 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. Thi s 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 si te, 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 t echnologies 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 f inal
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 an y 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 previoussection, 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

C omment: 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 app ropriately, 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: 2809 1
Other EPA Comment Codes and Descriptions: 3210 3.2.1. Comments Generally in Support of the
ApproachComment: 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 press ure issues that would be encountered in drilling through a CCS

site.

Individual Response: 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 own ers 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 requir ements; 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 i t 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 drinkin g 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

formation s 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 theproposed 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 gasreservoirs which are analogous to CCS sites. There are some excellent examples

of off

- shore technologies for drilling through salt formation s 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 formati ons 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

acce ss 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

Comm ent: 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 n oted 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 a re some excellent examples of off

- shore technologies for drilling through salt
formations and shallow gas pockets that involve the same type of pressure issuesthat would be encountered in drilling through a CCS site.

Individual Response: EPA acknowle dges 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 1 6, 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: 28210Other 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 inte rsect 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

tha t 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James J. Dooley

C ommenter 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 formatio ns without becoming pathways
for the migration of previously stored CO2 out of the target storage formation.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 wil l 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

forma tion. 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 drillin g 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 injectio n 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

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Notes:

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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:

### 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 address ing 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 exi sting 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 pos tinjection 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

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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 RuleComment: 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 i njection 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 potenti ally
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
strateg ies 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 Respons e: 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 operatio ns, 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 tribalboundaries, 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

infor m 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 respo nses to comments on the proposed GS

rule.

EPA Team Member: Cadmus --Natalie

Draft Status:
Date Uploaded: 14

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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. Sta te 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"

curren tly 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 th e 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 i ssues 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 Cla ss 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, allowi ng 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 developingany comprehensive regulatory framework.

Indi vidual 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., pipel ine 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

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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 a lso 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 th e 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 regulateaspects of CCS projects, such as issues related to property rights and financial
incentives beyond injection and storage, and the Agency’s regulation o n 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

beli eves 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

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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 delegate d
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 aspect s of carbon capture and storage in issues relating to property
rights and financial incentives beyond injection and storage. However, it isIndividual 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 int erests 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 Uploa ded: 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.

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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: C ompletion 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 perfectworld. 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 g eologic 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
negati ve 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 potenti ally 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 project s 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:

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Shannon Angielski
Commenter Organization: Coal Utili zation 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 -B oxer draft legislation propose an 83% reduction in U.S. GHG emissions (relative to 2005emissions) 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 t echnology 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 E nergy 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

c ommercial 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, whi le 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 b e 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.

Indivi dual 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: John Borkovich
Commenter Organization: California State Water Resources Control Board (SWRCB)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

penetra tions" 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

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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 r equirements:

- 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;- the required level of financ ial 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 No tice 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

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- 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

unders tand 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 sa mple 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 concern s are resolved, large
scale projects should not be allowed.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 minim um, 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Mary Munn
Commenter Organization: Fond du Lac Reservation

EPA Letter ID: 0347

EPA C omment 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, th e 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.EPA Team Member:

Draft Status:
Date Uploaded: 24

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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

Co mment: 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 (UI C) Program and (2) establish Federal
regulations that are specifically tailored to CO2 injection for GS. NRGsubmitted comments last December on EPA’s proposal to regulate CO2 GS under the UIC program. See 73 Fed. Reg. 43492 (July 25, 2008).

Individua l 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 St atus:
Date Uploaded: 14

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Verne Shortell
Commenter Organization: NRG Energy, Inc.

E PA 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 Rul e 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 requirement s 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 site

specific characteristics. For additional information on the adaptive approach a nd site

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

EPA Team Member:

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Date Uploaded: 30

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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. A s 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 res ponsibly 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 res ponse to similar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 24

- 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: 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] t echnologies," 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

se questration 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 mo st 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:______________________________________________________________________________________

____________________________________________________ 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 one size

- 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 r equirements
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:

Dr aft Status:
Date Uploaded: 24

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Thomas Curtis
Commenter Organization: American Water Works Association (AWWA)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 opportun ity

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

w

ater 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 434 92) 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:Date Uploaded: 28

- SEP

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Comm enter 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 w e 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 NODAEPA'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.

Carbo n 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 techn iques, 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

I ssue 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.

Indivi dual 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 IndustryEPA Letter ID: 0541

EPA Comment ID: 28328

Comment: injection above the lowermost USDW. API is still concerned, though, that by

b eing 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 Busine ss 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 take n into account. We believe it needs to
be factored into a whole range of issues ranging from site characterization, toarea of review, to containment requirements. The regulations should encourage

site

- specific, performance

- based determinations at the p ermitting 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 E PA’s response to similar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 26

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Nam e: 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)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 show ing 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 re cord 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

associ ation 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 si milar 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 McManusCommenter 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 m ust 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

Comme nt: 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 regu latory site characterization and risk review may
be appropriate.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 so le 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 sen sitive 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 RequirementsThere are no minimum criteria for either the thickness or the permeability of
the confining zone. Although there may be some rationality in lithifie d (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

fee t 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 Summar y:

Response to Comment Code:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Name: John McManus Commenter Organization: American El ectric 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.(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 owne r 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, ass umptions 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, i f 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, t he
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 oper ating
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;(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, i dentify 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 be en 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 operato r:

"(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 thissubsection; 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 revi ew 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 w aive 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 1 46.25(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 a rea 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. P lease 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 PriestCommenter Organization: Oregon Department of Environmental Quality (DEQ)

EPA Letter ID: 0366

EPA Comment ID: 2 7912

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 acknowled ge 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
sequestrati on 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 Organizati on: 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 adequ ate.

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 M ember:

Draft Status:
Date Uploaded: 26

- JAN

- 10

Notes:

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

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

EPA Comment Code: 5200 5.4. Comments on the Proposed Financ ial 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 wi th 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 comm ents.

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.______________________________________________________________________________________

____________________________________________________ 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

- HQ OW- 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 Assuran ce 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: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 post injection site car e 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 cost s 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 theDirector 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 a ctions 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. Pl ease 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 Rou ndtable 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 i nvestments 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: T his 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 U ploaded: 26

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara Priest
Commenter Organization: Oregon Department of Environment al 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 environmen tal 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:

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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______________________________________________________________________________________

____________________________________________________ Commenter Name: G.H. Holliday Commenter Organization: Holliday Environmental Services, Inc. EPA Letter ID: 0326 EPA Comment ID: 27862

Comment: The Agencies do n ot 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 bring s 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:(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 newl y- 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 inject ion 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 con tact 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 th e 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;(E) D own

- 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 ca sing 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 ma y 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 an d
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 t he 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;(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 fo r 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 In jection 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 annulusespermanently 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: 27913Comment: 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 lo wermost 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 tha t 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 impac t 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 i s 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 continuousoperation without a significant interruption. By that we mean that the gro ut
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 ho urs 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 re sponse to similar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 26

- JAN

- 10

Notes:

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EPA Comment Code: 53 00 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 : 28063Comment: (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 o wner 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 w ith 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 ana lyst 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 interva ls

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, spo ntaneous potential, porosity, caliper, gamma ray and any
other logs the Director requires based on site specific conditions and risk based 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 mecha nical
integrity of injection wells, which may include one or more of the following:(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 represe ntative 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 representa tive 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: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) Loggin g, 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 th e 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 c omment 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 Upload ed: 26

- JAN

- 10

Notes:

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EPA Comment Code: 5350 5.7. Comments on the Proposed Operating Requirements (146.88)

EPA Tea m 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: 28064

Comment: (f) Injection well operating require ments

(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 appr oved 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:Date Uploaded: 26

- JAN

- 10

Notes:

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EPA Comment Code: 5400 5.8. Comments on the Proposed MIT Requirements (146.89)

EPA Team Member:

Draft Status:
Date Uploaded: J uly 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 specif ied 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).(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

an d 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 ac tivity 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

pro posed 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: 27922

Comment: 146.89 Mechanical integrit y

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 G S 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:

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EPA Comment Code: 5450 5.9. Comments on the Proposed Monitoring Requirements (146.90)

EPA Team Member:

Draft Status:
Date Upl oaded: July 16, 2009

Notes:

Comment Summary:

Response to Comment Code:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Name: Dwig ht 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)

Commen t: 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 themobilization 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 ex perimental 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 experi ence 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, i ncluding tracers, surface air/soil gas
monitoring and microseismic monitoring may be appropriate and useful in thecontext 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 det ectors" 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

prog ram 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 m onitoring 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 sit e.

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 n ot 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

- approve d
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 pre

existing 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: 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 mus t 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 fr equency 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 d ata) 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:(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,

oper ating 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 site specific 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 theproposed 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

Commen t: 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 berequired 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 corrosi on 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 448 05Issue Topic from EPA's NODA

Comprehensive laboratory tests are being applied to the development and field testing of monitoring strategies that can detect migration of fluids into
shallow aquifers and assess potential geochemical impacts.

Carbo n 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 specifi c 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 circums tances. 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 experimentalcontext 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 agai nst 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 suchtechnologies 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 p rojects. 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

clarif ies 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: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

characte ristics 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 ope rating 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 d ioxide 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;(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 a n 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
operatio nal 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 Direct or 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 deter mines 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 perm itted. 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);(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 propo sed 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; in cluding 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 thearea 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,

re cord 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 perme able 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 analysi s 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

r esults of the formation testing program or other data, and with the materials

used to construct the well;(11) Proposed stimulation program and a determination that stimulation will not
compromise containment;

(12) The results of the formation testin g 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) In jection 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.Individual Response: This comment pertains to EPA’s proposed GS rule (73 FR 43492) and is
outside the scope o f 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 Summ ary:

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 i njection
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 submi tted 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:(A) Appropriate testing or determination of bottomhole reservoir pressure;

(B) Approp riate 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
speci fied 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 pl an, 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 repo rt 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: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:

______________________________________________________________________________________

____________________________________________________ Commente r 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 r ules 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 anapproved 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 comm ents 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 post injection 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 cons idering entry into GS operations. Criteria fordetermining 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 paragra ph (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 car e and site closure plan must include the
following information:(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 freque ncy 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 thereis 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

- inject ion 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
pl ug 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) Documentat ion 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 t hat may penetrate the injection and confiningzone(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 file d, 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

Comme nt: 146.93 Post injection site care and closureWe 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.

I ndividual 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

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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 Res ponse: 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 Res ponse Requirements (146.94)

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: 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 acti ons 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 char acterize 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 Dire ctor 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 theemergency 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 it s 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 agr eed
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 Acti on

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.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 O rganization: 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!Individual Response: The final rule is based on the most recent GS

- related data, information, and

scientific research available. EPA int ends 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

info rmation 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 comment s on the proposed rule in the rulemaking docket.

EPA Team Member:

Draft Status:
Date Uploaded: 24

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- 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 r eporting 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:Date Upl oaded: 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 rathe r 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

o utside 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

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- 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 thedevelopment 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 s hould 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 in dustry 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 simila r comments.

EPA Team Member:

Draft Status:
Date Uploaded: 24

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kyle Isakower

Comme nter 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

p rojects 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 thro ugh 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 w orkload 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 obtainingprimacy for this program.

Individual Response: This com ment 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 "brig ht 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

defin e 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 commonview 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 numbe r 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.

Recommen ded 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 considere d 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 deleg ation 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) a re 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."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 ar e 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 reservoi r 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 i njection 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 u nderground 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 me chanical 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 Multi Stakeholder 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 verificationrequirements 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. Pl ease see responses to comments on the
proposed rule for EPA’s response to similar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 26

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- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: James P. Sims
Commenter Organization: Western Business Roundtable

EPA Letter ID: 0357

EPA Comment ID: 28226

Other EPA Commen t 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 whe reby 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 devel oping 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 field s, 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 regulato ry 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 o f 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 int egration 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 ot her 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

ac tivities, 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

EP A Letter ID: 0357

EPA Comment ID: 28227Comment: 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 categori zation 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

cours e, 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 actu ally 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 t o 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

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No tes:

______________________________________________________________________________________

____________________________________________________ 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 inc lusion in the proposed regulations of default provisions that simply
presume universal application. We believe that approach is problematic. It istoo early to fully understand precisely which methods or technologies will
ultimately prove optimal.

Ind ividual 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:

Dr aft Status:
Date Uploaded: 26

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Pamela F. Faggert
Commenter Organization: Dominion R esources 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 ga s (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 comment s 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 im pose 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 (7 3 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

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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 complete ly 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

rec overed. 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 prot ection 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 re search community needsto 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 non traditional geologic sequestration technology. We need a measu red 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 be havior 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

h armful 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 si milar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 26

- JAN

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara Priest
Commenter Organization: Oregon Department of Environmental Quality (DEQ)

EPA Letter ID: 0366

EPA Comment ID: 27910

Comment: EOR/EGRWe suggest keeping the programs for EOR/EGR and geo logic 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Barbara Priest
Commenter Organization: Oregon Department of Environmental Quality (DEQ)

EPA Letter ID: 0366

EPA Comment ID: 27917

Comment: No n- 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 ha zardous 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 a dministrative 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 -C O2 contaminants only as specifically
addressed in a facility's permit and a statement that the non

- C02 contaminantsmust 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 rule s 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 Na me: 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 cha llenges 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 futur e 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 dat a 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

prop osed 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: 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 integ ration 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 othe r 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

r ule.

EPA Team Member:

Draft Status:
Date Uploaded: 24

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Doran

Comm enter Organization: Spectra Energy Corp

EPA Letter ID: 0385

EPA Comment ID: 28144Comment: 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 site specific 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 Agen cy’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 ex ample, 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, reas onable, 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 case s, 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 site specific 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 whic h 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 co mments on the proposed GS rule.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 simil ar comments.

EPA Team Member:

Draft Status:
Date Uploaded: 24

- AUG

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Brianne Metzger

- Dor an 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

Partnershi p 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 d ata 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 proc ess. (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.

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

C omment: 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 go od public perception of CCS and
would ensure the long

- term integrity of the program. The International RiskGovernance 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,

2 008).

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. I n 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 sequest ration 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 no t 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:Date Uploaded: 26

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jim Stovall
Commenter Organization:

EPA Letter I D: 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 exc lusive 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 hassecured the Director’s approval for an operation, the operator cannot take any
actions on these leases without the concurrent approval of the BL M."

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 Me mber:

Draft Status:
Date Uploaded: 26

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jim Stovall
Commenter Organization:

EPA Le tter 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

sh ould 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 No tice 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: 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

a ppropriate 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 Organ ization: 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 ofvaluable experience in this area and should play a key role in managing carbon
capture and storage projects. In fact, stat es 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 on ly 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 R esponse: 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 implement ation 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 prev ious
section, lines 99 to 106. This comment appears twice in this report, once for each set of line numbers.

______________________________________________________________________________________

____________________________________________________ Commen ter Name: Steve Crookshank
Commenter Organization: API National Trade Association of the US Oil and Natural Gas Industry

EPA Letter ID: 0541

EPA Comment ID: 28326Comment: 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

req uirements. 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 expe rience 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 operat ions 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 comprehens ive 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

Not es:

Comment Summary:Response to Comment Code:



### Individual Comments

______________________________________________________________________________________

____________________________________________________ Commenter Name: Anonymous8 Commenter Organiz ation: 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 Pro gram’s authority under the GS rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 15

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commen ter 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!Individual Response: This comment is outside the scope of the Notice of Data Availabili ty and the
UIC Program’s authority under the GS rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 23

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- 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 solut ion 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 ou tfits 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 ener gy 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 ma rine 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:Date Uploaded: 15

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: G.H. Holliday
Commenter Organization: Holliday Environmental Services, Inc.

EPA Letter ID: 0325

EPA Comment ID: 2785 9

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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: G.H. Holliday
Commenter Organizatio n: 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 ver y 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 Contr ibute 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)

document s. The IPCC is a governmental body almost devoid of technically trained participants. IPCC is politically driven (Note that some of the IPCC critics inthis 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://ww w.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 clima te 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Na me: 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 (http://www.climatescience.gov/Library/sap/sap1

- 1/finalreport/default.htm) and (
http://www.hillsdale.edu/news/imprimis/archive/issue.a sp?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 posit ion 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 temperatu re 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 author ity under the GS rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 15

- JAN

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jef frey 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 reductio ns. 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 damagediscouraging 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 irrepar able 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 basi s 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 o f 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

Labor atory

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 req uirement that the USEPA examine
potential impacts associated with CCS on USDWs, the reader is left with thestrong 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 sa linity. 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Anonymous9
Commenter Organization:

EPA Letter ID: 0335

EPA Comment ID: 28213

Comment: CCS is a bad idea to sta rt 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:Date Uploaded: 15

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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 su bsidized 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 co mment 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:

T he 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 formati ons 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 g round will be caving in under our

civilization.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. coalresources while promoting reduction of greenhouse gas emissions. The American

Individual Resp onse: 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 res earch 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 unreaso nably 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 com ment 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: 28396Comment: Exa mple:

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 hydrost atic 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 uncerta in 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 G S rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 15

- JAN

- 10

Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Emily Rochon

Comm enter 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 cur rently considering permitting the burying of CO2 in undergroundformations 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 clima te 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

th at 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

Comme nt: 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 f ederal 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 sin gle plant. 73 Fed. Reg. 44354, 44492 (July 30, 2008). AEP believes that our decades of research, engineeringexperience, 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 c omment 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 Comme nt 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 emission s, 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 proje cts.

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: 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)]. Tri State believes that decades of involvement
with the management of fossil fuel combustion materials provides our
organization with a valuab le 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

Co mment: 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 WaterAct (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 mitig ate 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 a cross 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

Ch ange (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 M cCain

- 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."And:

"Today's proposal provides a regulato ry 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 wi thout
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
implementati on 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

- HQ OW- 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.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 a nd
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 Baden Wurttemberg (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 th e 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: 27895Comment: Even as this proposed rule is being considered, the EPA is soliciting
"applications to conduct research to support the development of sound risk

managemen t 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 Just ice: 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 o il, 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.

EP A 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 feasibilityof 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 formati on.

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

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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:

______________________________________________________________________________________

____________________________________________________ Comment er Name: Mary Munn
Commenter Organization: Fond du Lac Reservation

EPA Letter ID: 0347

EPA Comment ID: 27899Comment: · 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 reali ty, 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 Te am 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: 27902

Comment: The commitment of resources; human, material, and capital, required to construct
the network of pipelines and wel ls 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

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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 sy stem. 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 comp eting

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 ex ample,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

n ew 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 com ment 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

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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

environment ally 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 a uthority under the GS rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 15

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- 10

Notes:______________________________________________________________________________________

____________________________________________________ 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 appro ach 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.

Accordi ng 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, b oth 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; post injection 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 t he 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 eitheroffshore 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

t he 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 t he GS rulemaking.

EPA Team Member:

Draft Status:
Date Uploaded: 15

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jeanne Herb

C ommenter 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

aut horities. 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 itsrulemaking.

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 wa ters.
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 Protec tion, 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 sectio n 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 Age ncy 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Jeanne Herb
Commenter Organization: New Jersey Department of Environmental Protection (NJDEP)

EPA Letter I D: 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 as sociatedCO2plumes) 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 app licability 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

prote ction 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

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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 fuel fired power plants, including two large coal

- fired pow er 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

I ndividual 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

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Notes:______________________________________________________________________________________

____________________________________________________ Commenter Name: Diane VanDe Hei
Commenter Organization: Association of Metropolitan Water Agencies (AMWA)

EPA Letter ID: 0365

E PA 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Scott Anderson
Commenter Organization: Environmental Defense Fund (EDF)

EPA Letter ID: 0376

EPA Commen t 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 emi ssions 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 geologi c sequestration in saline reservoirs, but also in oil & gas reservoirs, and (3)
expeditiously develop airside accounting, monitoring and reporting provisionsfor injected CO2 [FOOTNOTE 1]. We are somewhat encouraged by EPA’s statements

Individual Resp onse: 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

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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

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Notes:

______________________________________________________________________________________

____________________________________________________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 a nd 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 GH Gs 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

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Notes:

______________________________________________________________________________________

____________________________________________________ Commenter Name: Kristin Henry
Commenter Organization: Sierra Club, Environmental Law Program

EPA Letter ID: 0388

EPA Comment ID: 28295

Comment: Sierra Club cont inues 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 agreethat in order to avoid the worst cons equences 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

- target report.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

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- 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 hav e a few concerns that are outside the Scope of the Rule. These are risks
to human health, air, ecosystems; and illegal dumps.We recommend that a detailed Risk Assessment be performed that covers all
aspects of the CS operation, from cradle to grave. T his 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 Upload ed: 15

- JAN

- 10

Notes: