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.
Chesapeake Energy 12/18/2008 1 :34 :15 PM PAGE 2/004 Fax Serverp,1 

(It 

Chesa~ eake 

lENERGV 

December 18, 2008 

VIA FACSIMILE (202) 556-9744 

AND CERTIFIED MAIL # 7008 0150 0001 6908 2324 

Water Docket 

US EPA (2822T) 

1200 Pennsylvania Ave., NW 

Washington, DC 20460 

DEC 1 8 2008 

Re: Comments on EPA Federal Requirements under the Underground Injection 

Control (UIC) Program for Carbon Dioxide (C02) Geologic Sequestration (GS) 

Wells: Proposed Rule 

EPA-HQ-OW-2008-0390 

Gentlemen : 

Chesapeake Energy appreciates the opportunity to make the following comments on 

the referenced rulemaking . 

The primary focus of our comments is that additional language is needed in the 

proposed rule to clarify that existing and future Class II wells used for underground 

injection of naturally occurring acid gases, including C02, at gas production and/or gas 

processing sites are exempted from regulation under the new Class VI well designation . 

We have also made comments regarding (1) state primacy for Class VI wells, and (2) 

liability after "site closure" . 

We appreciate the opportunity to comment on this proposed regulation . 

Sincerely, 

Grover R. Campbell 

Environmental Engineer 

DEC 18 2008 

Regulatory Department 

Chesapeake Energy Corporation 

P.O. Box 18496 " Oklahoma City, UK 73154-0496 " 6100 N. Western Avenue " Oklahoma City, OK 73118 

405.848 .8000 " fax 405.879.7908 
Chesapeake Energy 12/18/2008 1 :34 :15 PM PAGE 3/004 Fax Serverp,2 

December 18, 2008 

Comments on EPA-HQ-OW-2008-0390 

Page 1 

Chesapeake Energy Comments on EPA's Proposed Rule for C02 GS 

1 . Exemption of Class II Wells from the proposed Class VI Well Classification 

Section G of the Preamble to the proposed rule (G. How Would This Proposal Affect 

Existing Injection Wells Under the U1C Program?) reads in part: "The requirements in 

today's proposal, if finalized, would not specifically apply to Class II injection wells . . ." 

Other statements in the preamble suggest that the EPA's intent is to not regulate 

existing or future Class II wells as Class VI wells unless an owner or operator of such a 

well chooses to reclassify the well for geologic sequestration of a C02 stream. However, 

the applicability language and definitions in the proposed rule do not achieve that goal. 

More specific language is needed in order for the public, regulatory agencies and courts 

to know without a doubt that Class II wells used for underground injection of naturally 

occurring acid gases, including C02, at gas production and/or gas processing sites are 

exempt from the Class VI requirements . The same applies for C02 injection wells at 

Enhanced Oil or Gas Recovery (EORIEGR) field operations . Therefore, the following 

language revisions should be made . 

Revise 40 CFR Part 144 Subpart H, 146.81(b) to read: 

This subpart applies to wells used to inject carbon dioxide specifically for the 

purpose of geologic sequestration, i .e ., the long-term containment of a gaseous, 

liquid or supercritical carbon dioxide stream in subsurface geologic formations . 

(1) Unless applicability is requested by the owner or operator, existing and future 

Class II wells that inject C02 and other fluids, which are brought to the surface in 

connection with conventional oil or natural gas production operations, are exempt 

from the requirements of this subpart. 

(2) Unless applicability is requested by the owner or operator, existing and future 

Class 11 wells that inject C02 and other fluids, which are operated in connection 

with an Enhanced Oil or Gas Recovery (EOR/EGR) field operation, are exempt 

from the requirements of this subpart. 

2 . State Primacy for Class VI Wells 

The EPA noted in the preamble to the proposed rule that it is seeking comment on the 

merits and possible disadvantages of allowing primacy approval for Class VI wells 

independent of other well classes . 

We prefer that no state have primacy approval for Class VI wells unless that state also 

has primacy approval for Class II wells . Our concern is that a state with primacy for only 

the new Class VI wells may assume that the only permitting option for injection of C02 

underground for any purpose, including the injection of naturally occurring acid gases, 
Chesapeake Energy 12/18/2008 1 :34 :15 PM PAGE 4/004 Fax Serve~~3 

December 18, 2008 

Comments on EPA-NQ-OAR-2008-0318 

Page 2 

including COZ, at gas production and/or gas processing sites, would be a Class VI 

permit . This could lead to confusion and delays in obtaining a Class II permit . Any state 

granted primacy for the new Class VI wells should also have primacy for Class 11 wells 

so that their permitting agency is familiar with the purpose of Class II wells and the less 

restrictive requirements for Class II wells. 

3 . Liability after "Site Closure" 

In the preamble to the proposed rule, the EPA states that "Trust responsibility for 

potential impacts to USDWs remains with the owner or operator indefinitely under 

current SDWA provisions ." In essence, the EPA has chosen not to address the issue of 

long term liability after "site closure", which is the period of time after the end of the 

post-injection site care phase of the GS project. 

Prior to issuing a final rule on C02 sequestration, the EPA must address this liability 

issue. While we do not offer a specific approach to the problem of "site stewardship 

after site closure", we do believe that the approach taken should be in line with the basic 

recommendations of the Interstate Oil and Gas Compact Commission (IOGCC) as 

outlined in "C02 Storage: A Legal and Regulatory Guide for States". 

The IOGCC has proposed a two-stage Closure Period and Post-Closure Period . The 

Closure Period is defined as that period of time when the plugging of the injection well 

has been completed and continuing for a defined period of time (10 years unless 

otherwise designated by the State Regulatory Agency) after injection activities cease and the injection well is plugged . During this Closure Period, the operator of the storage 

site would be responsible to maintain an operational bond and individual well bonds. 

The individual well bonds would be released as the wells are plugged . At the conclusion of the Closure Period, the operational bond would be released and the liability for 

ensuring that the site remains a secure storage site during the Post-Closure Period 

would transfer to the state. During the Post-Closure Period, the financial resources 

necessary for the state or a state contracted entity to engage in future monitoring, 

verification, and remediation activities would be provided by a state-administered trust 

fund. The IOGCC proposed the creation of an industry-funded and state-administered 

trust fund as the most effective and responsive "care-taker" program to provide the 

necessary oversight during the Post-Closure Period . The trust fund would be funded by 

an injection fee assessed to the site operator and calculated on a per-ton basis, at the point of custody transfer of the C02 from the generator to the site operator. 
Letter ID: 0271 

Commenter: Grover Campbell 

Organization: Chesapeake Energy 

Letter ID: 0271 Comment ID: 22892 Letter Lines: 40 to 44 ; 58 to 89 

Comment Code: 2046 1.5.2.3 Continuing to classify CO2 injection for EOR/EGR as Class II/ 

dividing line between Class II and Class VI (seeking comment) 

Comment: The primary focus of our comments is that additional language is needed in the 

proposed rule to clarify that existing and future Class II wells used for 

underground injection of naturally occurring acid gases, including CO2, at gas 

production and/or gas processing sites are exempted from regulation under the 

new Class VI well designation. 

1 . Exemption of Class II Wells from the proposed Class VI Well Classification 

Section G of the Preamble to the proposed rule (G. How Would This Proposal 

Affect Existing Injection Wells Under the U1C Program?) reads in part: "The 

requirements in today's proposal, if finalized, would not specifically apply to 

Class II injection wells. . ." Other statements in the preamble suggest that the 

EPA's intent is to not regulate existing or future Class II wells as Class VI 

wells unless an owner or operator of such a well chooses to reclassify the well 

for geologic sequestration of a CO2 stream. However, the applicability language 

and definitions in the proposed rule do not achieve that goal. More specific 

language is needed in order for the public, regulatory agencies and courts to 

know without a doubt that Class II wells used for underground injection of 

naturally occurring acid gases, including CO2, at gas production and/or gas 

processing sites are exempt from the Class VI requirements. The same applies for 

CO2 injection wells at Enhanced Oil or Gas Recovery (EOR/EGR) field operations . 

Therefore, the following language revisions should be made. 

Revise 40 CFR Part 144 Subpart H, 146.81(b) to read: 

This subpart applies to wells used to inject carbon dioxide specifically for the 

purpose of geologic sequestration, i.e., the long-term containment of a gaseous, 

liquid or supercritical carbon dioxide stream in subsurface geologic formations. 

(1) Unless applicability is requested by the owner or operator, existing 

and future Class II wells that inject CO2 and other fluids, which are brought to 

the surface in connection with conventional oil or natural gas production 

operations, are exempt from the requirements of this subpart. 

(2) Unless applicability is requested by the owner or operator, existing 

and future Class 11 wells that inject CO2 and other fluids, which are operated in 

1
connection with an Enhanced Oil or Gas Recovery (EOR/EGR) field operation, are 

exempt from the requirements of this subpart. 

Individual Response: EPA agrees that injection of CO2 for the primary purpose of enhancing 

oil and gas recovery should remain under the Class II Program. The Agency believes that the 

nature and risks of CO2 injection for the primary purpose of long term storage pose different 

risks than injection for the primary purpose of EOR, and therefore has developed new Class VI 

regulations to address these unique risks. For example, the volume of CO2 anticipated to be 

injected for long term storage is significantly greater than for EOR operations. Reservoir 

pressure conditions will also be different, with Class VI injection operations involving large 

volumes of CO2 and likely having higher pressures within their storage formations than Class II 

EOR projects. 

The GS rule language, at §146.81(b), clearly states that the rule applies to wells that inject 

carbon dioxide for the purpose of long term sequestration. Wells that inject carbon dioxide 

primarily for the purpose of enhanced recovery or oil or gas are considered Class II wells, and 

they are not required to meet the requirements in the final GS rule. 

Letter ID: 0271 Comment ID: 22893 Letter Lines: 92 to 107 

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

Comment: 2. State Primacy for Class VI Wells 

The EPA noted in the preamble to the proposed rule that it is seeking comment on 

the merits and possible disadvantages of allowing primacy approval for Class VI 

wells independent of other well classes. 

We prefer that no state have primacy approval for Class VI wells unless that 

state also has primacy approval for Class II wells. Our concern is that a state 

with primacy for only the new Class VI wells may assume that the only permitting 

option for injection of CO2 underground for any purpose, including the injection 

of naturally occurring acid gases, including CO2, at gas production and/or gas 

processing sites, would be a Class VI permit. This could lead to confusion and 

delays in obtaining a Class II permit. Any state granted primacy for the new 

Class VI wells should also have primacy for Class 11 wells so that their 

permitting agency is familiar with the purpose of Class II wells and the less 

restrictive requirements for Class II wells. 

Individual Response: EPA disagrees that Class VI primacy should only be granted to states 

with Class II programs. Many states that intend to sequester CO2 may not have oil and gas 

programs (e.g., states with extensive saline formations and no oil and gas resources). 

Furthermore, states with primacy for other well classes (e.g., Class I or deep Class V wells) 

would also possess a great deal of technical expertise regarding injection technology and an 

understanding of Section 1422 of SDWA. 

2
While EPA acknowledges that states that have not obtained primacy under SDWA Section 1422 

for other well classes may be less familiar with implementing the UIC program under that 

section of the Act, the Agency does not believe this would preclude their ability to effectively 

obtain and implement primacy for Class VI wells. EPA does not intend to limit primacy of Class 

VI wells to only states with primacy for Class II wells—any state that can demonstrate in its 

primacy application that they have developed 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 will be granted primacy for Class VI 

wells. 

EPA also plans to support states as needed to help them develop and implement their Class VI 

programs. EPA will allow states to apply for primacy for Class VI independent of other well 

classes regardless of whether or not they have primacy for other well classes. EPA is developing 

guidance materials and plans to conduct on-line and in-person training for States, Tribes, and 

Territories to describe the process of applying for and receiving primary enforcement 

responsibility (primacy) for GS Class VI wells under Section 1422 of SDWA, as well as the 

technical and administrative issues on developing GS regulations that are the equivalent of 

minimum Federal criteria and requirements. The guidance will be available at 

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

Letter ID: 0271 Comment ID: 22894 Letter Lines: 109 to 142 

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

Comment: 3. Liability after "Site Closure" 

In the preamble to the proposed rule, the EPA states that "Trust responsibility 

for potential impacts to USDWs remains with the owner or operator indefinitely 

under current SDWA provisions." In essence, the EPA has chosen not to address 

the issue of long term liability after "site closure", which is the period of 

time after the end of the post-injection site care phase of the GS project. 

Prior to issuing a final rule on CO2 sequestration, the EPA must address this 

liability issue. While we do not offer a specific approach to the problem of "site 

stewardship after site closure", we do believe that the approach taken should be 

in line with the basic recommendations of the Interstate Oil and Gas Compact 

Commission (IOGCC) as outlined in "CO2 Storage: A Legal and Regulatory Guide for 

States". 

The IOGCC has proposed a two-stage Closure Period and Post-Closure Period. The 

Closure Period is defined as that period of time when the plugging of the 

injection well has been completed and continuing for a defined period of time 

(10 years unless otherwise designated by the State Regulatory Agency) after 

injection activities cease and the injection well is plugged. During this 

Closure Period, the operator of the storage site would be responsible to maintain 

3
4

an operational bond and individual well bonds.The individual well bonds would be 

released as the wells are plugged. At the conclusion of the Closure Period, the 

operational bond would be released and the liability for ensuring that the site 

remains a secure storage site during the Post-Closure Period would transfer to 

the state. During the Post-Closure Period, the financial resources necessary for 

the state or a state contracted entity to engage in future 

monitoring, verification, and remediation activities would be provided by a 

state-administered trust fund. The IOGCC proposed the creation of an industryfunded and state-administered trust fund as the most effective and responsive 

"care-taker" program to provide the necessary oversight during the Post-Closure 

Period . The trust fund would be funded by an injection fee assessed to the site 

operator and calculated on a per-ton basis, at the point of custody transfer 

of the CO2 from the generator to the site operator. 

Individual Response: Under the final GS rule, once an owner or operator has met all regulatory 

requirements under Part 146 for Class VI wells and the Director has approved site closure 

pursuant to requirements at §146.93, the owner or operator will generally no longer be subject to 

enforcement for regulatory noncompliance. Furthermore, their financial instrument as required 

under §146.85 will be released if it was not used. However, even if a site closure is approved 

under §146.93, an owner or operator may be held liable for regulatory noncompliance (including 

violation of 40 CFR 144.12) in certain circumstances. For example, an owner or operator may be 

held liable for regulatory noncompliance even after site closure was approved if the Director 

relied on erroneous information (e.g., erroneous modeling data) provided by the owner or 

operator when approving site closure. 

Separate from EPA’s authority to enforce regulatory compliance, an owner or operator may be 

subject to a §1431 response order even after proper site closure is approved under §146.93. 

Under §1431 the Administrator may require an owner or operator to take necessary response 

measures if he or she receives information that a contaminant is present or is likely to enter a 

public water system or an USDW, which may present an imminent and substantial endangerment 

to the health of persons, and the appropriate State and local authorities have not acted to protect 

the health of such persons. The action may include issuing administrative orders or commencing 

a civil action for appropriate relief against the owner or operator of a Class VI well. If the owner 

or operator fails to comply with the order, they may be subject to a civil penalty for each day in 

which such violation occurs or failure to comply continues. 

Furthermore, after site closure an owner or operator may remain liable under tort and other 

remedies, or under other federal statutes including, but not limited to, Clean Air Act, 42 U.S.C. 

§§ 7401-7671; CERCLA, 42 U.S.C. § 9601-9675; and RCRA, 42 U.S.C. § 6901-6992. 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. See the final rule preamble for further discussion of 

EPA's final approach.