This comment letter response contains two parts:   

(1) The original submittal from the commenter.

(2) A data base printout of EPA’s response to each point raised by the commenter.

Notes about the response letters:

• The response letters were generated by a data base used to track the content of all public

comment submittals and ensure that the Agency responds to each. Each comment letter

was assigned a Letter ID that corresponds to the last four digits of the docket number of the

original comment (as posted on www.regulations.gov).

• Each response letter includes: comment text; an EPA‐assigned comment code; and an

individual response. These are described and explained below.  

• The data base contains Comment text from the letters submitted by commenters.  

Many hard copy letters were scanned into electronic format for inclusion in the data

base. As a result, there may be some typographical errors attributable to optical

character recognition issues.  However, all original submittals were reviewed in the

process of drafting responses to ensure that the comment content was understood and

appropriately addressed.

• The content of each comment letter was divided into topic areas and assigned a unique

Comment ID.  Additionally, one or more Comment Codes (i.e., unique topic area ID) was

assigned to each discrete point raised by a commenter. This information was added to

the data base. To inform final rulemaking decisions, all comments and information

received on a given topic were reviewed by technical experts in each rule area (e.g., on

construction requirements).  

• Following decisions on the final rule requirements, Individual responses were drafted

by topic area to ensure completeness and consistency of the responses with the final

rule and other responses to similar comments.  Each discrete point made by a

commenter was given a unique response.

• Upon completion of comment responses, all information was entered into the data base.

Each letter response is a compilation of each comment and its individual response,

compiled in the order of the original comment letter.  As a result of this process, there is

repetition in the response text.  The Agency believes this approach ensures completeness

and attention to each comment letter that was submitted.   

• All comments in a topic area were reviewed, evaluated, and responded to concurrently.  

Responses on each topic area are compiled and are also available in the rulemaking docket.
 

288 North 1460 West • Salt Lake City, UT 

Mailing Address: P.O. Box 144870 • Salt Lake City, UT 84114-4870 

Telephone (801) 538-6146 • Fax (801) 538-6016 • T.D.D. (801) 536-4414 

www.deq.utah.gov 

Printed on 100% recycled paper 

State of Utah 

JON M. HUNTSMAN, JR. 

Governor 

GARY HERBERT

Lieutenant Governor

Department of Water Quality Board 

Joe Piccolo, Chair 

Environmental Quality Paula Doughty, Vice-Chair

William J. Sinclair 

Acting Executive Director 

DIVISION OF WATER QUALITY

Walter L. Baker, P.E. 

Director 

David F. Echols 

Merritt K. Frey 

Darrell H. Mensel 

Leland J. Myers 

Jay Ivan Olsen 

Gregory L. Rowley

Steven P. Simpson 

William J. Sinclair 

Daniel C. Snarr 

Phil Wright 

Walter L. Baker, 

 Executive Secretary

December 24, 2008 

Water Docket 

Environmental Protection Agency 

Mailcode: 2822T 

1200 Pennsylvania Avenue, NW

Washington DC 20460 

RE: EPA Docket Number: EPA-HQ-OW-2008-0390 

Dear Sir or Madam:

The Utah Division of Water Quality is pleased to submit the attached comments on the EPA's 

Proposed Rule for Federal Requirements Under the Underground Injection Control (UIC) 

Program for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells. 

If you have any questions or comments regarding the attached document, please feel free to 

contact Candace Cady by phone at (801) 538-9260 or by email at ccady@utah.gov. 

Sincerely, 

Walter L. Baker, P.E. 

Director

WB:LAL:RH:CC: 

cc: 

F:\wp\UIC\CARBON CAPTURE & SEQUESTRATION\EPA\CCGSRules\Utah DWQ Comments.doc 

File: EPA Correspondence 
 

288 North 1460 West • Salt Lake City, UT 

Mailing Address: P.O. Box 144870 • Salt Lake City, UT 84114-4870 

Telephone (801) 538-6146 • Fax (801) 538-6016 • T.D.D. (801) 536-4414 

www.deq.utah.gov 

Printed on 100% recycled paper 

State of Utah 

JON M. HUNTSMAN, JR. 

Governor 

GARY HERBERT 

Lieutenant Governor

Department of Water Quality Board 

Joe Piccolo, Chair 

Environmental Quality Paula Doughty, Vice-Chair

William J. Sinclair 

Acting Executive Director 

DIVISION OF WATER QUALITY 

Walter L. Baker, P.E. 

Director 

David F. Echols 

Merritt K. Frey 

Darrell H. Mensel 

Leland J. Myers 

Jay Ivan Olsen 

Gregory L. Rowley 

Steven P. Simpson 

William J. Sinclair 

Daniel C. Snarr 

Phil Wright 

Walter L. Baker, 

 Executive Secretary

Comments on the Federal Requirements Under the Underground Injection Control (UIC) Program 

for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells; Proposed Rule 

Published in the Federal Register on July 25, 2008 (Volume 73, Number 144) 

Docket Number: EPA-HQ-OW-2008-0390 

Prepared by Candace C. Cady, PG 

Utah 1422 UIC Program 

Utah Department of Environmental Quality, Division of Water Quality 

Introduction 

Thank you for the opportunity to submit comments on the proposed rule for carbon dioxide 

geologic sequestration wells. We commend EPA’s efforts in engaging international, national, 

state, and local experts from a broad spectrum of relevant fields to inform the development of the 

proposed rule. Finalizing the rule for carbon dioxide geologic sequestration wells will make 

significant progress in removing one of the identified (GAO, September 2008) barriers to 

implementing large-scale commercial carbon capture and geologic sequestration (CCGS) projects, 

namely the legal and regulatory uncertainties associated with CCGS, particularly with regards to 

injection and storage of CO2. 

General Comments 

While CCGS is only one technology in a portfolio of many that will need to be implemented to 

achieve carbon emissions stabilization, it is most amenable to mitigating the emissions from large 

stationary CO2 sources, particularly carbon-based fossil fuel power plants which account for 

nearly 80% of the cumulative total CO2 emissions from large stationary sources (IPCC, 2005). 

Furthermore, CCGS has been identified as the critical enabling technology for reducing CO2 

emissions significantly while allowing the use of carbon-based fossil fuels, especially coal, to 

meet the world's energy demands (The Future of Coal, 2007). Meeting carbon emissions 

stabilization goals will be more easily achieved if mitigative measures are implemented sooner 

rather than later. Therefore, while the enabling CCGS legal and regulatory framework must 

provide for the protection of ground water and other natural resources, it must not contain 

elements that would hinder the timely deployment of commercial scale CCGS projects. 

Carbon sequestration is a unique type of injection undertaken for a unique and critical purpose. It 

is not hydrocarbon storage nor is it industrial hazardous waste disposal. A hybrid approach should 

be taken in the development of rules that will facilitate the expeditious deployment of CCGS 
Page 2 

technology on a large and commercial scale. The development of rules for Class VI CO2 

injection wells should logically begin with the existing rules for Class II enhanced oil recovery 

(EOR) wells using CO2 thereby building on the experience of 30+ years during which these type 

of CO2 wells have been in operation. From this starting point, CCGS rules can be tailored to 

account for the unique features of geologically sequestered CO2; namely large volumes, reactivity 

of CO2 in the presence of water, buoyancy, mobility, and extremely long time period of 

sequestration. Beginning with existing rules for Class I industrial wells as a reference for the 

proposed rule (page 43503 of the federal register notice) sends the message that injection of CO2 

for geologic sequestration is akin to industrial waste disposal rather than management of the major 

greenhouse gas it is. 

Carbon capture and geologic sequestration encompasses more than the injection of captured CO2. 

The development of the entire enabling legal and regulatory framework, in which legal and 

regulatory barriers have been identified and resolved, to implement CCGS on a commercial scale 

will require multi-media, multi-agency, and multi-statute consideration, including possible 

amendments of existing statutes. In addition to removing barriers to implementation, this legal 

and regulatory framework will need to be flexible and adaptable to facilitate the incorporation of 

new information and experiences gained from the numerous pilot CO2 sequestration projects 

currently in their infancy. Whereas CO2 pipeline technology and legal and regulatory framework 

have reached a status of relative maturity due primarily to the use of CO2 in enhanced oil 

recovery for the past 30+ years, CO2 capture technology as applied to coal-fired power plants is 

just beginning to develop. Statutes and regulations governing the injection and storage of CO2 

should be adaptive to the constraints of the other elements of an entire CCGS project (and vice 

versa) as they are identified. 

Specific Comments on Topics 

In the preamble to the proposed rule, EPA asked for comments on approximately 50 topics. 

Following are our comments on some of those topics. 

APPROPRIATENESS OF CLASS VI CLASSIFICATION FOR GS WELLS

We support the creation of a new class of injection well for carbon dioxide geologic 

sequestration wells. This action acknowledges the unique nature of and purpose for this new 

well class and facilitates the development of enabling regulations for the rapid deployment of 

CCGS projects. We do not, however, support the limitation of carbon sequestration below the 

lowermost underground source of drinking water (USDW). The determination for siting a 

CCGS project should be based on assessment of site specific conditions including the presence 

of an adequate upper and lower confining zone to protect USDW both above and below the 

injection zone. 

"GRANDFATHERING" OF EXISTING CO2 INJECTION WELLS

We support EPA's intent to allow "grandfathering" of the construction requirements for 

existing Class I, II or V wells that are converted to Class VI wells. However, conversion to a 

Class VI well should only be allowed after an assessment of the geochemical interaction 

between the CO2, previous injectate, injection zone matrix and fluid indicates there will be no 

deleterious effects due to the commingling of different injection streams that might 
Page 3 

compromise the CCGS project or endanger USDWs. This is especially relevant when 

converting Class I and Class V wells to Class VI wells. 

PROHIBITIONS – COAL SEAMS, BASALTS, SALT DOMES, SHALES, OTHER FORMATIONS, 

We do not support the categorical prohibition of CO2 geologic sequestration in coal seams, 

basalts, salt domes, shales or any other formation. EPA states in the preamble to the proposed 

rule that "[t]hese formations are limited in geographic and geologic distribution throughout the 

U.S., and their technological or economic viability as GS [geologic sequestration] sites have 

not been demonstrated." For this very reason, these formations should not be eliminated as 

possible sequestration reservoirs. Ongoing demonstration projects conducted under the 

Department of Energy may yet demonstrate their viability. 

DEFINING CO2 STREAM TO EXCLUDE HAZARDOUS WASTE/SUBSTANCE UNDER RCRA/CERCLA 

We consider potential liability under RCRA and/or CERCLA a major deterrent to developing 

and deploying CCGS projects and one that must be addressed. Towards removing this as a 

barrier to CCGS, we strongly encourage EPA to address the issues surrounding the 

composition of the injected CO2 stream. These issues include: providing a clear description 

of the analytical methods for characterizing the CO2 stream, providing a clear description of 

the limitation on the CO2 stream composition so as to avoid inclusion under RCRA or 

CERCLA, and investigating thoroughly the possibility of RCRA and CERCLA exemption for 

CCGS while still providing protection to USDWs and other natural resources. Since capture 

and separation technology is still being developed for large stationary CO2 sources, it is 

important to have a clearly defined target for design objectives. 

ALLOWING FOR DIRECTOR DISCRETION IN REQUIRING ADDITIONAL CONTAINMENT ZONES

We support EPA's intention to provide Director's discretion in requiring additional confining 

and containment zones that could further impede vertical fluid movement and allow for 

pressure dissipation. This acknowledges the importance and merit of implementing a riskbased, site-specific approach in characterizing a site for CCGS projects. This allows for 

flexibility in setting permit requirements for the protection of USDWs and other natural 

resources thereby increasing the number of sites that could potentially be used for CCGS. 

COMPUTATIONAL MODELING

We support the use of multiphase models in predicting the movement of the CO2 plume and 

injection zone fluids given the multiphase nature of the injectate particularly in the early stage 

of the CCGS project. However, we also emphasis the importance of the use of geochemical 

modeling in addressing the reactivity of CO2 in the presence of water and other reactive 

components in the matrix and fluids of the injection and confining zones. 

PROPRIETARY MODELING

We do not support the use of proprietary models for modeling CCGS projects. There should 

be complete transparency in all aspects of CCGS allowing for peer review of the models and 

assumptions associated with them. This process would be hindered by the use of proprietary 

models. Furthermore, there are numerous powerful modeling codes available in the public 
Page 4 

domain that have already been used in predicting fluid movement and geochemical reaction 

for CCGS. 

RE-EVALUATION OF THE AREA OF REVIEW

Given that there is not extensive experience in tracking the movement of large volumes of 

injected CO2 and associated formation fluids, we support EPA's intent to require periodic reevaluation of the Area of Review. We feel strongly that monitoring results should inform the 

Director in determining an appropriate frequency for re-evaluation and that this should be an 

iterative process resulting in the continuing refinement of the site-specific predictive model. 

ALLOWING FOR DIRECTOR DISCRETION IN PHASED APPROACH TO CORRECTIVE ACTION

We support EPA's intention to allow Director's discretion in allowing a phased approach to 

corrective action for wells that penetrate the injection zone within the Area of Review. As 

stated above, this allows for a risk-based, site-specific approach in setting permit requirements 

for the protection of USDWs and other natural resources thereby increasing the number of 

sites that could potentially be used for CCGS. 

WELL DRILLING TECHNIQUES 

Given the success of horizontal drilling techniques in facilitating geologic sequestration of 

CO2 in the In Salah project in Algeria, we strongly support allowing innovative drilling 

techniques in CCGS projects thereby allowing the development of these projects in geologic 

settings that otherwise might not be amenable to CCGS such as in formations with limited 

permeability. 

REQUIREMENT OF INJECTION BELOW THE LOWERMOST USDW 

We do not support EPA's proposed categorical requirement of injection CO2 below the 

lowermost USDW. We feel this would restrict the areas in which CCGS could be deployed. 

If site-specific hydrogeologic conditions, well construction, and operating parameters can be 

shown to provide protection for all USDWs and other natural resources above and below the 

injection zone, the CCGS project should be allowed. 

ELECTRONIC REPORTING

We agree with EPA that electronic reporting will reduce reporting burden and will facilitate 

tracking of CCGS projects. However, the "electronic format acceptable to the Director" 

should not constitute a financial or resource burden to the owner / operator or to the regulating 

agency required to report to EPA on UIC program activity. Until that time when the 

regulating agency has developed a data flow to the National UIC Database, we strongly urge 

EPA to develop an online service for submitting CCGS information such as is currently in 

place for submitting Program Activity Measures (PAMs) and UIC inventory. 

LIABILITY

Currently, under the Safe Drinking Water Act, liability remains with the owner/operator 

indefinitely. We believe this represents a significant barrier to the implementation of CCGS 
Page 5 

projects so long as there are perceived long-term risks after closure. Alternative scenarios 

have been proposed (IOGCC Sept 5, 2007; de Figueiredo, 2007) that would significantly 

reduce this barrier by establishing a CO2 sequestration fund capitalized by a CO2 storage tax 

or fee paid by the owner/operator on a per-ton-of-CO2-injected basis. This fund would be 

used by the long-term liability management entity to conduct on-going monitoring, to plug and 

abandon orphaned CO2 storage wells, to pay out compensation for damages, and to remediate 

a CO2 storage facility. 

We encourage the EPA to enable an alternate liability scheme to the one offered currently by 

the Safe Drinking Water Act in which liability remains with the owner/operator indefinitely. 

This may require an amendment to the Safe Drinking Water Act. 

PRIMACY OF CLASS VI WELLS

We encourage EPA to allow primacy approval for Class VI wells independent of the other 

classes of injection wells. This would allow the state agency that is best positioned for 

implementing the Class VI program to apply for primacy for the program or to apply for an 

amendment to an existing primacy application. This would facilitate the rapid deployment of 

commercial-scale CCGS projects. 

PERMIT DURATION

Permit duration may be less than the duration of the project in primacy states with the option 

for permit renewal. This offers the operator and regulator the opportunity to amend the permit 

as new information relevant to the project becomes available. The Utah DWQ also will 

require the inclusion of a re-opener clause in the permit to allow revision of the permit to 

accommodate extenuating circumstances and new information relevant to the permit. 

References Cited 

Federal Actions Will Greatly Affect the Viability of Carbon Capture and Storage As a Key 

Mitigation Option, Report to the Chairman of the Select Committee on Energy Independence and 

Global Warming, House of Representatives, U.S. Government Accountability Office (GAO), 

September, 2008. 

IPCC, 2005: IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared by Working 

Group III of the Intergovernmental Panel on Climate Change [Metz, B., O.Davidson, H.C. de 

Coninck, M. Loos, and L.A. Meyer (eds.)]. Cambridge University Press, Cambridge, United 

Kingdom and New York, NY, USA, 442 pp. 

The Future of Coal: Options for a Carbon-Constrained World, An Interdisciplinary MIT Study, 

2007 

IOGCC. 2007. Storage of Carbon Dioxide in Geologic Structures; A Legal and Regulatory Guide 

for States and Provinces. Prepared by the Interstate Oil and Gas Compact Commission. September 

25, 2007. 
Page 6 

The Liability of Carbon Dioxide Storage, Mark Anthony de Figueiredo, MIT Ph.D Thesis, 

February 2007. 
Letter ID: 0253 

Commenter: Walter L. Baker 

Organization: Utah Division of Water Quality 

Letter ID: 0253 Comment ID: 22336 Letter Lines: 58 to 68 

Comment Code: 1420 1.2.1.1 Support the GS rulemaking 

Comment: Introduction 

Thank you for the opportunity to submit comments on the proposed rule for carbon 

dioxide geologic sequestration wells. We commend EPA’s efforts in engaging 

international, national, state, and local experts from a broad spectrum of 

relevant fields to inform the development of the proposed rule. Finalizing the 

rule for carbon dioxide geologic sequestration wells will make significant 

progress in removing one of the identified (GAO, September 2008) barriers to 

implementing large-scale commercial carbon capture and geologic sequestration 

(CCGS) projects, namely the legal and regulatory uncertainties associated with 

CCGS, particularly with regards to injection and storage of CO2. 

Individual Response: EPA believes that the creation of a new injection well class (VI) under the 

existing UIC Program is necessary to enable the use of GS as a climate change mitigation 

technology in a manner that protects USDWs from endangerment. EPA agrees that the UIC 

Program, under the authority of the SDWA, provides a strong framework for regulating injection 

of CO2 for GS and adds that the GS regulation tailors the UIC requirements to address the 

unique issues associated with large-scale GS including large injection volumes, the relative 

buoyancy of CO2, its corrosivity in the presence of water, the potential presence of impurities in 

captured CO2, and its mobility within subsurface geologic formations. 

EPA agrees that the implementation of the GS rule in a manner that ensures protection of 

USDWs from endangerment is important to establishing a foundation for further advances in the 

field of CO2 GS, and acknowledges the need for regulatory certainty. The final GS requirements 

provide a level of certainty by setting forth unique requirements for GS. These requirements 

include: the tailored AoR delineation process (per §146.84), the types of monitoring appropriate 

to GS projects (per §146.90), and the post-injection site care process (per §146.93). 

EPA agrees that input of and participation by a wide spectrum of stakeholders is a vital 

component of successful rulemaking. The Agency appreciates the degree of cooperation, 

participation, and active dialogue between the EPA and stakeholders and will continue to work 

with stakeholders and experts as it implements the GS rule. 

Letter ID: 0253 Comment ID: 22337 Letter Lines: 70 to 84 

Comment Code: 1000 1. General and Administrative Comments 

Comment: General Comments 

1
While CCGS is only one technology in a portfolio of many that will need to be 

implemented to achieve carbon emissions stabilization, it is most amenable to 

mitigating the emissions from large stationary CO2 sources, particularly carbonbased fossil fuel power plants which account for nearly 80% of the cumulative 

total CO2 emissions from large stationary sources (IPCC, 2005). Furthermore, 

CCGS has been identified as the critical enabling technology for reducing CO2 

emissions significantly while allowing the use of carbon-based fossil fuels, 

especially coal, to meet the world's energy demands (The Future of Coal, 2007). 

Meeting carbon emissions stabilization goals will be more easily achieved if 

mitigative measures are implemented sooner rather than later. Therefore, while 

the enabling CCGS legal and regulatory framework must provide for the protection 

of ground water and other natural resources, it must not contain elements that 

would hinder the timely deployment of commercial scale CCGS projects. 

Individual Response: EPA acknowledges the comment. EPA agrees that GS is one technology 

in a portfolio of options, including solar, wind, biomass, and geothermal, that could be deployed 

to reduce CO2 emissions; however these technologies are outside the scope of the UIC GS 

rulemaking. EPA clarifies that the GS regulation does not promote or encourage the use of GS; 

rather it is designed to ensure consistency in permitting underground injection of CO2 at GS 

operations across the United States and provide requirements to prevent endangerment of 

USDWs in anticipation of the eventual use of GS to reduce CO2 emissions. EPA clarifies that 

mitigating climate change is outside the scope of the GS rulemaking. Please see the remainder of 

EPA's responses to this comment for further details. For additional information on EPA's final 

regulatory approach, please see the final rule and preamble as well as the rulemaking docket. 

Letter ID: 0253 Comment ID: 22338 Letter Lines: 86 to 101 

Comment Code: 1200 1.1 General comments about the rulemaking 

Comment: Carbon sequestration is a unique type of injection undertaken for a unique and 

critical purpose. It is not hydrocarbon storage nor is it industrial hazardous 

waste disposal. A hybrid approach should be taken in the development of rules 

that will facilitate the expeditious deployment of CCGS technology on a large 

and commercial scale. The development of rules for Class VI CO2 injection wells 

should logically begin with the existing rules for Class II enhanced oil 

recovery (EOR) wells using CO2 thereby building on the experience of 30+ years 

during which these type of CO2 wells have been in operation. From this starting 

point, CCGS rules can be tailored to account for the unique features of 

geologically sequestered CO2; namely large volumes, reactivity of CO2 in the 

presence of water, buoyancy, mobility, and extremely long time period of 

sequestration. Beginning with existing rules for Class I industrial wells as a 

reference for the proposed rule (page 43503 of the federal register notice) 

sends the message that injection of CO2 for geologic sequestration is akin to 

industrial waste disposal rather than management of the major greenhouse gas it 

is. 

2
Individual Response: EPA clarifies that the GS rule does not promote or encourage the use of 

GS; rather it ensures consistency in permitting underground injection of CO2 at GS operations 

across the United States and provide requirements to prevent endangerment of USDWs in 

anticipation of the eventual use of GS to reduce CO2 emissions. EPA adds that the GS regulation 

builds upon the long-standing protective framework of the UIC Program, which has been 

regulating the injection of billions of gallons of fluids for decades, including wells used for 

enhanced oil recovery. It includes requirements that address the unique technical criteria for 

permitting GS wells that are tailored the existing UIC regulatory framework to address the 

unique nature of CO2 injection for GS. 

Please see the remainder of EPA's responses to this comment letter for further details. For 

additional information on EPA's final regulatory approach, including the discussion of how this 

rulemaking affect existing injection wells under the UIC Program, please see the final rule and 

preamble as well as the rulemaking docket. 

Letter ID: 0253 Comment ID: 22339 Letter Lines: 103 to 117 

Comment Code: 1250 1.1.1.4 Flexibility is needed (performance-based standards) 

Comment: Carbon capture and geologic sequestration encompasses more than the injection of 

captured CO2. The development of the entire enabling legal and regulatory 

framework, in which legal and regulatory barriers have been identified and 

resolved, to implement CCGS on a commercial scale will require multi-media, 

multi-agency, and multi-statute consideration, including possible amendments of 

existing statutes. In addition to removing barriers to implementation, this 

legal and regulatory framework will need to be flexible and adaptable to 

facilitate the incorporation of new information and experiences gained from the 

numerous pilot CO2 sequestration projects currently in their infancy. Whereas 

CO2 pipeline technology and legal and regulatory framework have reached a status 

of relative maturity due primarily to the use of CO2 in enhanced oil recovery 

for the past 30+ years, CO2 capture technology as applied to coal-fired power 

plants is just beginning to develop. Statutes and regulations governing the 

injection and storage of CO2 should be adaptive to the constraints of the other 

elements of an entire CCGS project (and vice versa) as they are identified. 

Individual Response: The Agency believes that the Class VI requirements balance site-specific 

flexibility with USDW protection. Rather than setting performance or technology-based 

standards for GS projects, EPA is adopting a flexible approach, where operators of GS projects 

would develop and implement site-specific plans for delineating the AoR, testing and monitoring 

the site, performing corrective action, and post-injection site care. EPA believes that the plans—

which would be reviewed and approved by the Director and periodically updated throughout the 

life of the project—promote an ongoing dialogue between the operator and the Director that will 

encourage use of the most appropriate technologies for a particular project. 

EPA adds that it is using an adaptive approach to regulating GS under the UIC Program. Even 

3
after finalization of the GS regulation, EPA plans, every six years, to collect and review project 

data on GS research projects to determine whether the appropriate amount and types of 

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

modifications to the requirements are appropriate or necessary. 

EPA clarifies that the Class VI GS requirements are designed to ensure that, where deployed, GS 

is conducted in a manner that protects USDWs from endangerment. Encouraging investment in 

CCS projects and facilitating deployment are outside the scope of the GS rulemaking. 

Letter ID: 0253 Comment ID: 22340 Letter Lines: 118 to 122 

Comment Code: 1000 1. General and Administrative Comments 

Comment: 

Specific Comments on Topics 

In the preamble to the proposed rule, EPA asked for comments on approximately 50 

topics. Following are our comments on some of those topics. 

Individual Response: EPA acknowledges the comment. Please see the remainder of EPA's 

responses to this comment for further details. For additional information on EPA's final 

regulatory approach, please see the final rule and preamble as well as the rulemaking docket. 

Letter ID: 0253 Comment ID: 22341 Letter Lines: 124 to 129 

Comment Code: 2020 1.5.1 Support Class VI designation 

Comment: APPROPRIATENESS OF CLASS VI CLASSIFICATION FOR GS WELLS 

We support the creation of a new class of injection well for carbon dioxide 

geologic sequestration wells. This action acknowledges the unique nature of and 

purpose for this new well class and facilitates the development of enabling 

regulations for the rapid deployment of CCGS projects. We do not, however, 

Individual Response: EPA agrees that tailored requirements for Class VI wells are necessary to 

address the unique nature of injecting large volumes of CO2 and to ensure that USDWs are 

protected from endangerment. The GS rule contains tailored requirements for the permitting, 

geologic site characterization, AoR and corrective action, well construction, operation, 

mechanical integrity testing, monitoring, well plugging, post-injection site care, and site closure 

of GS wells that directly address issues unique to the nature of large-scale CO2 injection for GS. 

Letter ID: 0253 Comment ID: 22342 Letter Lines: 129 to 134 

Comment Code: 4324 2.4.4.1.2 Comments opposed to requiring injection below the lowermost 

4
USDW 

Comment: regulations for the rapid deployment of CCGS projects. We do not, however, 

support the limitation of carbon sequestration below the lowermost underground 

source of drinking water (USDW). The determination for siting a CCGS project 

should be based on assessment of site specific conditions including the presence 

of an adequate upper and lower confining zone to protect USDW both above and 

below the injection zone. 

Individual Response: EPA acknowledges that there are limited circumstances where injection 

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

endangerment, as long as appropriate protections are in place. 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 for injection into non-USDW formations above and/or between USDWs. 

Additionally, the final GS rule does not categorically preclude or prohibit injection into any type 

of formation. 

It establishes: 1) requirements specifying information that owners or operators must submit, and 

Directors must consider, in consultation with PWSS Directors; 2) procedures for public notice of 

a waiver application and for Director-Regional Administrator communication; 3) the waiver 

issuance process; and, 4) additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements to ensure USDW protection above and 

below the injection zone. 

EPA believes that these requirements will ensure USDW protection while providing flexibility to 

UIC program Directors and owners or operators who undertake CO2 injection for GS. 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. For 

additional information on the waiver approach, please see the final rule and preamble, as well as 

EPA's responses to comments on the Notice of Data Availability and Request for Comment. 

Letter ID: 0253 Comment ID: 22343 Letter Lines: 136 to 145 

Comment Code: 2060 1.5.3 Comments on grandfathering of existing wells (seeking comment) 

Comment: "GRANDFATHERING" OF EXISTING CO2 INJECTION WELLS 

We support EPA's intent to allow "grandfathering" of the construction 

requirements for existing Class I, II or V wells that are converted to Class VI 

5
wells. However, conversion to a Class VI well should only be allowed after an 

assessment of the geochemical interaction between the CO2, previous injectate, 

injection zone matrix and fluid indicates there will be no deleterious effects 

due to the commingling of different injection streams that might compromise the 

CCGS project or endanger USDWs. This is especially relevant when converting 

Class I and Class V wells to Class VI wells. 

Individual Response: EPA agrees and expects that any decision to convert a well for long term 

storage of CO2 will be made in the context of all available information about the site and history 

of injection. EPA agrees that many Class I, Class II, and Class V experimental technology wells 

are designed and constructed to withstand exposure to CO2. The final GS rule provides for the 

construction of these wells to be grandfathered per §146.81(c), 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). 

Following re-permitting of the well as Class VI, the project must be subject to the siting, 

operational, MIT, monitoring, reporting, plugging, and post-injection site care and site closure 

requirements in the final GS rule. This would most likely include an evaluation of the properties 

of the rock in the injection zone and fluid composition in the context of the proposed CO2 

injection, as the commenter suggests. See the discussion of EPA's final regulatory approach in 

the preamble to the GS rule for additional detail on these requirements. 

Letter ID: 0253 Comment ID: 22344 Letter Lines: 147 to 156 

Comment Code: 2160 1.6.3 Unmineable coal seams 

Comment Code: 2200 1.6.4 Other formation types 

Comment: PROHIBITIONS - COAL SEAMS, BASALTS, SALT DOMES, SHALES, OTHER 

FORMATIONS, 

We do not support the categorical prohibition of CO2 geologic sequestration in 

coal seams, basalts, salt domes, shales or any other formation. EPA states in 

the preamble to the proposed rule that "[t]hese formations are limited in 

geographic and geologic distribution throughout the U.S., and their 

technological or economic viability as GS [geologic sequestration] sites have 

not been demonstrated." For this very reason, these formations should not be 

eliminated as possible sequestration reservoirs. Ongoing demonstration projects 

conducted under the Department of Energy may yet demonstrate their viability. 

Individual Response: EPA clarifies that the GS rule does not categorically preclude injection of 

CO2 into any non-USDW formation types. The purpose of the GS rule is to ensure protection of 

USDWs from endangerment, and the rule requires that owners or operators demonstrate that 

wells are sited in suitable systems with geologic formations to receive and confine injected CO2, 

required at §146.83 of the GS rule. The Class VI siting, well construction and operation, 

monitoring and testing, and post-injection site care and site closure requirements are designed to 

6
ensure that injected CO2 remains within the target formation. If an owner or operator can 

demonstrate to the Director's satisfaction that GS in coal seams, basalts, salt domes, or shales can 

be accomplished in a manner that protects USDWs and meets all of the requirements of the GS 

rule, the project may be permitted as a Class VI well. 

EPA acknowledges that there may be risks associated with GS, particularly regarding GS into 

formations such as coal seams, basalts, salt domes, or shales, which have been the subject of 

limited experimental projects in the past. For this reason, the Agency is using an adaptive 

approach to regulate GS injection. EPA will collect and review project data on early GS projects, 

including those that inject into various formation types, to determine whether the appropriate 

amount and types of information and documentation are being collected. EPA plans, every six 

years, to collect and review data on GS projects to determine whether the appropriate amount 

and types of information and appropriate documentation are being collected, and to determine if 

modifications to the requirements are appropriate or necessary. 

Letter ID: 0253 Comment ID: 22345 Letter Lines: 158 to 171 

Comment Code: 1630 1.3.3 RCRA/hazardous waste issues (seeking comment) 

Comment Code: 1640 1.3.4 CERCLA issues (seeking comment) 

Comment: DEFINING CO2 STREAM TO EXCLUDE HAZARDOUS WASTE/SUBSTANCE 

UNDER RCRA/CERCLA 

We consider potential liability under RCRA and/or CERCLA a major deterrent to 

developing and deploying CCGS projects and one that must be addressed. Towards 

removing this as a barrier to CCGS, we strongly encourage EPA to address the 

issues surrounding the composition of the injected CO2 stream. These issues 

include: providing a clear description of the analytical methods for 

characterizing the CO2 stream, providing a clear description of the limitation 

on the CO2 stream composition so as to avoid inclusion under RCRA or CERCLA, and 

investigating thoroughly the possibility of RCRA and CERCLA exemption for CCGS 

while still providing protection to USDWs and other natural resources. Since 

capture and separation technology is still being developed for large stationary 

CO2 sources, it is important to have a clearly defined target for design 

objectives. 

Individual Response: The final GS rule retains the definition of a CO2 stream as proposed. The 

GS regulation applies to injection of CO2 for the purpose of GS, regardless of the source of the 

CO2. It is beyond the scope of the GS rule and the UIC Program’s authority to require or set 

standards for upstream generators of CO2 or purification facilities. For purposes of GS, the UIC 

program’s authority under the SDWA is limited to ensuring that GS projects are sited, 

constructed, operated, and closed in a manner that protects USDWs. 

With respect to the commenter’s concern about RCRA, EPA has decided to initiate a separate 

proposed rulemaking specifically to examine the issue of RCRA applicability to CO2 streams 

7
being geologically sequestered, including the possible option of a conditional exemption from 

the RCRA requirements for CO2 GS in Class VI wells. EPA will consider these comments as 

part of its development of that proposal. The Agency will consider issues particular to RCRA in 

the context of that separate rulemaking, and recommends that the commenter read that proposed 

rule when it is published. The Agency notes that commenters who wish to submit comments on 

the RCRA proposal will need to do so during the comment period for that rule. Finally, EPA also 

notes that the final GS rule, which adds new regulations for Class VI wells under the Safe 

Drinking Water Act (SDWA), is not making any changes to the RCRA regulations. 

Letter ID: 0253 Comment ID: 22346 Letter Lines: 173 to 181 

Comment Code: 3120 2.1.2 Need to identify additional confining and containment zones 

(seeking comment) 

Comment: ALLOWING FOR DIRECTOR DISCRETION IN REQUIRING ADDITIONAL 

CONTAINMENT ZONES 

We support EPA's intention to provide Director's discretion in requiring 

additional confining and containment zones that could further impede vertical 

fluid movement and allow for pressure dissipation. This acknowledges the 

importance and merit of implementing a risk-based, site-specific approach in 

characterizing a site for CCGS projects. This allows for flexibility in setting 

permit requirements for the protection of USDWs and other natural resources 

thereby increasing the number of sites that could potentially be used for CCGS. 

Individual Response: EPA agrees with the commenter that, in some situations, the presence of 

additional confining and containment zones above the primary (i.e., lowermost) confining zone 

can improve USDW protection from endangerment. The final regulation retains the requirement 

at §146.83(b) which affords the Director discretion to require owners or operators to identify and 

characterize additional zones. EPA believes that providing the Director discretion will allow 

consideration of a range of sites for GS, based on site-specific conditions and ensure USDW 

protection. EPA believes that requiring appropriate site characterization by the owner or operator 

(under §146.82) and providing an appropriate degree of flexibility to the Director to evaluate 

site-specific geologic data will afford the greatest protection of USDWs from endangerment. 

Letter ID: 0253 Comment ID: 22347 Letter Lines: 183 to 190 

Comment Code: 3310 2.2.1.1 Comments in favor of requiring computational models to 

delineate the AoR (seeking comment) 

Comment: COMPUTATIONAL MODELING 

We support the use of multiphase models in predicting the movement of the CO2 

plume and injection zone fluids given the multiphase nature of the injectate 

particularly in the early stage of the CCGS project. However, we also emphasis 

8
the importance of the use of geochemical modeling in addressing the reactivity 

of CO2 in the presence of water and other reactive components in the matrix and 

fluids of the injection and confining zones. 

Individual Response: EPA acknowledges the commenter’s support and agrees that predicting 

the complex multiphase, buoyant flow of the CO2, co-injectates, and compounds that may be 

mobilized due to injection requires the sophistication of computational models, as required at 

§146.84(c)(1). Models can predict CO2 fate and transport, as well as changes in formation 

pressure, in three dimensions, as a function of time in order to delineate the subsurface storage 

site and the AoR. Models can account for site-specific and predicted operating conditions as well 

as geologic heterogeneities and potential migration through faults, fractures, and artificial 

penetrations. 

EPA disagrees that geochemical modeling (i.e., reactive transport modeling) will be necessary 

for delineation of the AoR in all cases. EPA clarifies that the GS regulation requires that AoR 

modeling consider the chemical and physical properties of the injected stream and native fluids, 

but does not specifically require reactive transport modeling (146.84(c)(1)). As discussed in the 

preamble to the proposed GS regulation, EPA expects that AoR modeling will account for 

multiphase fluid flow processes, including density-driven flow (e.g., buoyancy). EPA believes 

that the purpose of AoR modeling is to predict the regions wherein fluid pressures increase 

and/or to which CO2 may be transported. Based on a review of the technical literature, EPA 

believes that, in many cases, reactive transport modeling will not be necessary to determine 

whether USDWs would be endangered. Any areas of geochemical disturbance would be within 

the modeled AoR as defined at 146.84(c). EPA adds that the Director has discretion to require 

additional modeling, including geochemical modeling, if he or she determines this to be 

necessary. EPA adds that the purpose of modeling is to target areas where geochemical 

monitoring should be performed. 

Letter ID: 0253 Comment ID: 22348 Letter Lines: 192 to 199 

Comment Code: 3350 2.2.1.5 Use of proprietary models for GS sites (seeking comment) 

Comment: PROPRIETARY MODELING 

We do not support the use of proprietary models for modeling CCGS projects. 

There should be complete transparency in all aspects of CCGS allowing for peer 

review of the models and assumptions associated with them. This process would 

be hindered by the use of proprietary models. Furthermore, there are numerous 

powerful modeling codes available in the public domain that have already been 

used in predicting fluid movement and geochemical reaction for CCGS. 

Individual Response: EPA disagrees that the use of proprietary models should be disallowed. 

EPA acknowledges the commenter’s concerns about the need to evaluate the inputs and 

assumptions used in these models, and EPA intends to allow the use of proprietary models in 

meeting the requirements for the GS regulation. EPA clarifies, however, that GS well operators 

9
using proprietary models are required to disclose, to the Director's satisfaction, the code 

assumptions, relevant equations, and scientific basis. Information including model assumptions 

and equations are used by the Director to inform his/her decision to issue the permit and ensure 

that the requirements are met and the GS well will not endanger USDWs. EPA adds that its 

Confidential Business Information requirements (144.5) will apply to the use of proprietary 

models. 

EPA clarifies, however, that GS well operators using proprietary models are required to disclose, 

to the Director's satisfaction, the code assumptions, relevant equations, and scientific basis. 

Information including model assumptions and equations are used by the Director to inform 

his/her decision to issue the permit and ensure that the requirements are met and the GS well will 

not endanger USDWs. 

Letter ID: 0253 Comment ID: 22349 Letter Lines: 201 to 208 

Comment Code: 3530 2.2.3.1 AoR reevaluation frequency (seeking comment) 

Comment: RE-EVALUATION OF THE AREA OF REVIEW 

Given that there is not extensive experience in tracking the movement of large 

volumes of injected CO2 and associated formation fluids, we support EPA's intent 

to require periodic re-evaluation of the Area of Review. We feel strongly that 

monitoring results should inform the Director in determining an appropriate 

frequency for re-evaluation and that this should be an iterative process 

resulting in the continuing refinement of the site-specific predictive model. 

Individual Response: EPA agrees with commenters that reevaluations of the AoR every ten 

years may not be sufficient, and has changed the minimum frequency for the AoR reevaluation 

from 10 years to 5 years, as specified in §146.84(e). EPA believes that this revised frequency 

addresses commenters' concerns that more frequent reevaluations are necessary to address the 

inherent uncertainties in modeling CO2 movement, the emerging nature of GS technology, riskbased targeting of monitoring activities, and the unique nature of CO2 GS. 

EPA agrees that site-specific information, including monitoring data, is an important factor in 

determining when AoR reevaluations are appropriate, and adds that the final rule also requires 

owners or operators to identify in the AoR and corrective action plan site-specific triggers for 

reevaluation before five years. EPA anticipates that anomalous monitoring data would be one 

such trigger. 

EPA recognizes that there are many unknowns about how GS projects will unfold including: the 

practicalities of permitting, operating, monitoring, and closing a GS project. To address this, the 

Agency is using an adaptive approach to regulating GS. The Agency 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 

10
modifications to the requirements are appropriate or necessary. 

Letter ID: 0253 Comment ID: 22350 Letter Lines: 210 to 217 

Comment Code: 3630 2.2.4.1 Comments in favor of allowing phased corrective action 

Comment: ALLOWING FOR DIRECTOR DISCRETION IN PHASED APPROACH TO 

CORRECTIVE ACTION 

We support EPA's intention to allow Director's discretion in allowing a phased 

approach to corrective action for wells that penetrate the injection zone within 

the Area of Review. As stated above, this allows for a risk-based, sitespecific approach in setting permit requirements for the protection of USDWs and 

other natural resources thereby increasing the number of sites that could 

potentially be used for CCGS. 

Individual Response: EPA acknowledges the commenter’s support of phased corrective action 

and agrees that phased corrective action may provide many benefits to a project including, but 

not limited to, spreading the burden of cost, avoiding delays in project start-up, allowing for use 

of future, improved corrective action techniques and addressing unanticipated changes in the 

movement of the CO2 plume or pressure front. EPA believes that the phased corrective action 

approach is appropriate for GS projects, and retained it at §146.84(b)(2)(iv) in the final GS 

regulation. 

EPA recognizes that a phased approach to corrective action may not be appropriate in all 

situations, and that the Director is in the best position to make decisions about the 

appropriateness of phased corrective action based on his or her knowledge of the local geologic 

and site conditions. For this reason, the GS rule affords the Director discretion in determining 

whether phased corrective action is appropriate at a given GS site. 

Letter ID: 0253 Comment ID: 22351 Letter Lines: 219 to 225 

Comment Code: 3840 2.3.2 Horizontal well drilling techniques (seeking comment) 

Comment: WELL DRILLING TECHNIQUES 

Given the success of horizontal drilling techniques in facilitating geologic 

sequestration of CO2 in the In Salah project in Algeria, we strongly support 

allowing innovative drilling techniques in CCGS projects thereby allowing the 

development of these projects in geologic settings that otherwise might not be 

amenable to CCGS such as in formations with limited permeability. 

Individual Response: In this final rule, EPA allows the use of horizontal wells at GS projects. In 

11
the proposed rule, EPA sought comment on the appropriateness of horizontal drilling techniques 

for Class VI wells, and commenters representing energy companies, electric utilities, the oil and 

gas industry, CCS associations, states, and the public, unanimously supported the concept and 

provided many reasons why horizontal wells could be beneficial at GS sites. Based on an 

evaluation of these comments and additional research by EPA, the Agency has concluded that 

horizontal wells that are properly constructed, logged, and tested for mechanical integrity (i.e., to 

meet the requirements of the GS rule) can ensure the protection of USDWs from endangerment. 

Letter ID: 0253 Comment ID: 22352 Letter Lines: 227 to 234 

Comment Code: 4324 2.4.4.1.2 Comments opposed to requiring injection below the lowermost 

USDW 

Comment: REQUIREMENT OF INJECTION BELOW THE LOWERMOST USDW 

We do not support EPA's proposed categorical requirement of injection CO2 below 

the lowermost USDW. We feel this would restrict the areas in which CCGS could 

be deployed. If site- specific hydrogeologic conditions, well construction, and 

operating parameters can be shown to provide protection for all USDWs and other 

natural resources above and below the injection zone, the CCGS project should be 

allowed. 

Individual Response: As described above, EPA acknowledges that there are limited 

circumstances where injection above the lowermost USDW can be performed in a manner that 

protects USDWs from endangerment, as long as appropriate protections are in place. 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 for injection into non-USDW formations above and/or 

between USDWs. 

EPA believes that proper siting, monitoring, and containment capacity are critical elements of 

Class VI injection for GS. However, the Agency also believes that injection into non-USDW 

formations above and between USDWs presents unique challenges related to movement of CO2 

in the subsurface, which requires a unique approach to ensure that USDWs are protected. 

Therefore, the Agency believes that additional requirements are appropriate and necessary for 

wells that would inject into non-USDWs above and between USDWs. 

Letter ID: 0253 Comment ID: 22353 Letter Lines: 236 to 245 

Comment Code: 4700 2.7 Proposed Recordkeeping and Reporting Requirements (40 CFR 

146.91) 

Comment Code: 4740 2.7.4 Electronic reporting (seeking comment) 

Comment: ELECTRONIC REPORTING 

We agree with EPA that electronic reporting will reduce reporting burden and 

12
will facilitate tracking of CCGS projects. However, the "electronic format 

acceptable to the Director" should not constitute a financial or resource burden 

to the owner / operator or to the regulating agency required to report to EPA on 

UIC program activity. Until that time when the regulating agency has developed 

a data flow to the National UIC Database, we strongly urge EPA to develop an 

online service for submitting CCGS information such as is currently in place for 

submitting Program Activity Measures (PAMs) and UIC inventory. 

Individual Response: EPA believes that electronic formatting is the most appropriate format for 

submitting Class VI project information to the Director, and based on comments received on the 

proposed rule, the majority of Class VI well owners or operators will have the capability to 

report electronically, and requires this at §146.91(e). 

Acknowledging that some States may have to develop electronic data systems to receive 

electronic information from the owner or operator, and that many States which already have 

electronic data systems will have to make changes to accommodate a new class of UIC well 

(Class VI), EPA believes that it is prudent to provide assistance by developing a central 

framework for the electronic system that will be used by States to gather and track owner or 

operator data. This will enable owners or operators to submit data without having to wait for a 

State to develop a system. It will also provide for standardized submissions across the country 

and enable States to focus State resources on reviewing and approving permit applications rather 

than building or upgrading separate, independent databases for GS information. 

EPA is developing guidance for states that describes the recordkeeping, reporting, and additional 

data management needs associated with GS activities and provides recommended guidelines on 

the types of data to be collected for tracking GS projects, reporting to EPA for compliance 

tracking, and transfer of data to EPA's GS data system. The recordkeeping and reporting 

guidance will be available on EPA's web site, at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

Letter ID: 0253 Comment ID: 22354 Letter Lines: 247 to 263 

Comment Code: 5460 2.9.2 Comments on transfer of liability for long-term care 

Comment: LIABILITY 

Currently, under the Safe Drinking Water Act, liability remains with the 

owner/operator indefinitely. We believe this represents a significant barrier 

to the implementation of CCGS projects so long as there are perceived long-term 

risks after closure. Alternative scenarios have been proposed (IOGCC Sept 5, 

2007; de Figueiredo, 2007) that would significantly reduce this barrier by 

establishing a CO2 sequestration fund capitalized by a CO2 storage tax or fee 

paid by the owner/operator on a per-ton-of-CO2-injected basis. This fund would 

be used by the long-term liability management entity to conduct on-going 

monitoring, to plug and abandon orphaned CO2 storage wells, to pay out 

compensation for damages, and to remediate a CO2 storage facility. 

13
We encourage the EPA to enable an alternate liability scheme to the one offered 

currently by the Safe Drinking Water Act in which liability remains with the 

owner/operator indefinitely. This may require an amendment to the Safe Drinking 

Water Act. 

Individual Response: EPA is working to create a nationally consistent financial responsibility 

regime within its authority to ensure that financial resources are available to protect USDWs 

throughout the life of the GS project. However, the authority under the SDWA does not extend 

to release owners or operators from long-term responsibility for the potential economic costs of 

impacts unrelated to USDWs. EPA does not have authority to transfer liability from one entity to 

another. In the UIC program, liability under SDWA §1423 remains with the owner or operator 

for all well classes until all regulatory requirements have been met. EPA understands that 

Congress is considering legislation that may address the liability issue. 

Under SDWA, EPA has the general authority to set financial responsibility requirements for 

injection well owners or operators to ensure that adequate resources are available to protect 

USDWs throughout the life of the GS project. However, this authority does not extend to 

allowing the Agency to create a financial instrument with EPA as the trustee, due to the 

restrictions of the Miscellaneous Receipts Act (MRA). The MRA requires that EPA deposit the 

funds it receives for the use of the Government into the Treasury, therefore funds would not 

necessarily be available for GS financial responsibility. 

Additionally, EPA does not have authority under SDWA to establish a trust fund for purposes of 

financial responsibility for Class VI projects. The Agency clarifies that the trust funds that are 

addressed as financial responsibility instruments on the GS rule are set up by individual owners 

or operators and are different from a national-level trust described by the commenters that would 

cover large numbers of GS projects. 

EPA clarifies that the GS regulation does not promote or encourage the use of GS; rather it is 

designed to ensure consistency in permitting underground injection of CO2 at GS operations 

across the United States and provide requirements to prevent endangerment of USDWs in 

anticipation of the eventual use of GS to reduce CO2 emissions. 

Letter ID: 0253 Comment ID: 22355 Letter Lines: 265 to 271 

Comment Code: 5610 2.11.1 Allowing partial primacy for Class VI wells (seeking comment) 

Comment: PRIMACY OF CLASS VI WELLS 

We encourage EPA to allow primacy approval for Class VI wells independent of the 

other classes of injection wells. This would allow the state agency that is 

best positioned for implementing the Class VI program to apply for primacy for 

the program or to apply for an amendment to an existing primacy application. 

This would facilitate the rapid deployment of commercial- scale CCGS projects. 

14
Individual Response: EPA agrees with commenters that states should be allowed to obtain 

primacy for Class VI wells independently of other well classes, and will allow independent 

primacy for Class VI wells under §145.1(i) of the final GS rule. In the past, EPA has not 

accepted UIC primacy applications for individual well classes under Section 1422 of SDWA. In 

other words, if a State wanted primacy for Class I wells, the State would also need to accept 

responsibility for Class III, IV, and V wells. This policy has been in place since the initiation of 

the UIC Program in the early 1980s and was intended to encourage states to take full 

responsibility for UIC programs, avoid duplication of efforts, and provide for administrative 

efficiencies. 

However, given the potential for CCS (encompassing capture, transportation, and geologic 

sequestration) to be an important part of a national priority to address climate change, EPA 

believes that providing states the flexibility to obtain primacy for Class VI wells independently 

of other well classes can help foster effective management of CCS. EPA believes that allowing 

independent Class VI primacy may encourage states to take responsibility for implementation of 

Class VI regulations and provide for a more comprehensive approach to managing CCS projects 

by promoting the integration of GS activities under SDWA into a broader framework for 

managing CCS. Furthermore, GS operations involve ancillary activities (e.g., pipeline 

operations, pore space ownership, land use rights, and surface access) for which states can call 

upon other authorities that exist at the state level (but outside UIC authority) to provide a more 

comprehensive CCS management approach. 

The Agency believes that it is important for states to use their unique efficiencies to promote 

adoption of this burgeoning and important technology, while assuring that USDWs are protected 

from endangerment through the UIC regulatory framework. EPA believes that, due to the 

importance of implementing an effective, comprehensive, and seamless CCS program, States 

should be provided the flexibility to obtain primacy for Class VI only. 

EPA also believes that allowing states to apply only for Class VI primacy will shorten the 

primacy approval process for states. EPA's willingness to accept independent primacy 

applications for Class VI wells represents a shift in its longstanding policy of discouraging 

"partial primacy." It is very important to note that this shift in policy allowing for Class VI 

primacy does not apply to any other well Class under Section 1422. EPA will continue to 

discourage applications for partial primacy for all other well types under Section 1422. 

EPA clarifies that states should be able to obtain primacy for Class VI wells independent of other 

well classes provided they develop regulations that are at least as stringent as the minimum 

Federal requirements (e.g., permitting, inspection, operation, monitoring, and recordkeeping 

requirements) provided in the final GS rule. EPA believes that existing programs can adapt their 

expertise to the new requirements for Class VI wells and will be able to develop a primacy 

application for Class VI wells under section 1422 of SDWA and ensure that their GS programs 

integrate into national climate change priorities and protect USDWs from endangerment. 

EPA recognizes that some states have already begun legislative efforts that are wider in scope 

than the Federal GS rule and believes that allowing Class VI primacy (independent of other well 

15
classes) may encourage states to take responsibility for implementation of a more comprehensive 

approach to managing CCS projects (e.g., capture, transportation, and geologic sequestration). 

Letter ID: 0253 Comment ID: 22356 Letter Lines: 273 to 280 

Comment Code: 5700 2.12 Comments on the proposed duration of Class VI permits (seeking 

comment) 

Comment: PERMIT DURATION 

Permit duration may be less than the duration of the project in primacy states 

with the option for permit renewal. This offers the operator and regulator the 

opportunity to amend the permit as new information relevant to the project 

becomes available. The Utah DWQ also will require the inclusion of a re-opener 

clause in the permit to allow revision of the permit to accommodate extenuating 

circumstances and new information relevant to the permit. 

Individual Response: The final rule maintains the lifetime permit provision and clarifies that the 

permit extends through the post-injection site care period (144.36(a)). It also adds a requirement 

that the Director review each Class VI permit at least once every 5 years to determine whether it 

should be modified, revoked and reissued, terminated or a minor modification made as provided 

in §§144.39, 144.40, or 144.41. The Director’s review will be informed by the owners’ or 

operators’ iterative reevaluation of the project. Specifically, the final rule includes a requirement 

that the AoR be reevaluated at least every five years, and also requires owners or operators to 

review and update the AoR and corrective action plan, the testing and monitoring plan, and the 

emergency and remedial response plan throughout the life of the project (146.84(e), 146.90(j), 

and 146.94(d)). Owners or operators must review each plan and identify necessary amendments 

or demonstrate to the Director that no amendment is needed. In no case can reviews occur less 

often than once every five years. The iterative process and subsequent plan reevaluations ensure 

that time and resources are committed to the most critical aspects of the permit in preventing 

endangerment to USDWs. EPA believes that the iterative process of developing and executing 

the various plans required of GS well operators in the final rule (e.g., for AoR and corrective 

action, testing and monitoring, injection well plugging, post-injection site care, and emergency 

and remedial response) is tailored to the unique aspects of—and is more appropriate for–GS than 

establishing a finite permit duration (e.g., ten years as suggested by some commenters). 

EPA emphasizes that the Director has the authority to revise the permit if project operations 

change or if the Director believes based on monitoring or operational data that the project may 

endanger USDWs. EPA has also added text to 144.39(a)(5) that permit modifications would be 

required if the Director determines that a modification is necessary based on an AoR 

reevaluation, amendments to any of the project plans, or a review of the testing and monitoring 

results. The Director may also choose to require minor permit modifications under 40 CFR 

144.41, depending on the extent of the plan amendment. All permit modifications, except minor 

modifications under 40 CFR 144.41, require an opportunity for public comment on the portion of 

the permit that is being reopened pursuant to requirements under 40 CFR 124. 

16
Letter ID: 0253 Comment ID: 22357 Letter Lines: 282 to 300 

Comment Code: 1000 1. General and Administrative Comments 

Comment: References Cited Federal Actions Will Greatly Affect the Viability of Carbon 

Capture and Storage As a Key Mitigation Option, Report to the Chairman of the 

Select Committee on Energy Independence and Global Warming, House of 

Representatives, U.S. Government Accountability Office (GAO), September, 2008. 

IPCC, 2005: IPCC Special Report on Carbon Dioxide Capture and Storage. Prepared 

by Working Group III of the Intergovernmental Panel on Climate Change [Metz, B., 

O.Davidson, H.C. de Coninck, M. Loos, and L.A. Meyer (eds.)]. Cambridge 

University Press, Cambridge, United Kingdom and New York, NY, USA, 442 pp. 

The Future of Coal: Options for a Carbon-Constrained World, An Interdisciplinary 

MIT Study, 2007 

IOGCC. 2007. Storage of Carbon Dioxide in Geologic Structures; A Legal and 

Regulatory Guide for States and Provinces. Prepared by the Interstate Oil and 

Gas Compact Commission. September 25, 2007. 

The Liability of Carbon Dioxide Storage, Mark Anthony de Figueiredo, MIT Ph.D 

Thesis, February 2007. 

Individual Response: PA acknowledges the comment. Please see the remainder of EPA's 

responses to this comment for further details. For additional information on EPA's final 

regulatory approach, please see the final rule and preamble as well as the rulemaking docket. 

17