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.
Peabodq 

p. 1 

701 Market Street 

PEABODY ENERGY St . Louis, Missouri 63101-1826 

314.342 .3400 

Sent Via Certified Mail 

December 17, 2008 

Water Docket 

U .S. Environmental Protection Agency 

Mailcode 2822T 

1200 Pennsylvania Avenue, N .W. 

Washington, DC 20460 

Docket ID No. EPA-HQ-OW-2008-0390 

DEC 2 2 2008 

Comments on Proposed Rule: Federal Requirements Under the Underground Injection 

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

Ladies and Gentlemen : 

The following general comments are submitted by Peabody Energy in response to 

EPA's proposed federal requirements under the Safe Drinking Water Act (SDWA) for 

the underground injection of carbon dioxide ("C02") for the purpose of geologic 

sequestration. EPA is to be commended for beginning the process to provide 

regulatory clarity for C02 sequestration . 

While Peabody Energy is generally supportive of the proposed rule, we believe the final 

rule should be modified to provide greater certainty for CCS projects that would like to 

proceed in the interim prior to promulgation of the final rule . The rule should also 

provide more certainty and flexibility to convert Class II EOR wells to permanent C02 

storage wells . As proposed, the site geology requirements seem to be unduly 

burdensome without any real additional safety benefit to underground sources of 

drinking water. Site geology should be considered on a case by case basis to prevent 

the categorical elimination of sites which may be technically acceptable. 

In an effort to reduce possible duplicate comments, we have reviewed the comments 

prepared by industry groups to which we belong and agree generally with the 

conclusions and approach of those comments. Those groups are as follows : 

Carbon Capture and Storage Alliance 

FutureGen Industrial Alliance DEC 17 2008 

Coal Utilization Research Council 

Gasification Technologies Council 

North American Caron Capture and Storage Association 

Western Business Roundtable 
We encourage EPA to consider seriously all of these comments which, if taken into 

consideration, could help create a more flexible, performance based Class VI program 

recognizing the characteristics of C02 injections . 

Thank you for considering our comments. Should you have any questions please 

contact me at 314 .342 .7613 or email to dtickner@peabodyenergy .com . 

Sincerely, 

Dianna Tickner 
Letter ID: 0262 

Commenter: Dianna Tickner 

Organization: Peabody Energy 

Letter ID: 0262 Comment ID: 22990 Letter Lines: 44 to 48 

Comment Code: 1420 1.2.1.1 Support the GS rulemaking 

Comment: The following general comments are submitted by Peabody Energy in response to 

EPA's proposed federal requirements under the Safe Drinking Water Act (SDWA) for 

the underground injection of carbon dioxide ("CO2") for the purpose of geologic 

sequestration. EPA is to be commended for beginning the process to provide 

regulatory clarity for CO2 sequestration. 

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. 

Letter ID: 0262 Comment ID: 22991 Letter Lines: 50 to 53 

Comment Code: 1210 1.1.1 Comments about the proposed rule 

Comment: While Peabody Energy is generally supportive of the proposed rule, we believe 

the final rule should be modified to provide greater certainty for CCS projects 

that would like to proceed in the interim prior to promulgation of the final 

rule. The rule should also provide more certainty and flexibility to convert 

Individual Response: EPA recognizes the importance of providing clear, flexible, scalable, and 

appropriate regulations. EPA believes that the GS regulation will provide certainty to industry 

and the public by providing consistency in requirements across the U.S. and transparency about 

what requirements apply to owners or operators. 

Please see the remainder of EPA's responses to this comment and the final rule and preamble for 

further details. 

Letter ID: 0262 Comment ID: 22992 Letter Lines: 53 to 54 

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) 

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Comment: rule. The rule should also provide more certainty and flexibility to convert 

Class II EOR wells to permanent CO2 storage wells. As proposed, the site geology 

Individual Response: The final Class VI regulations require that any owner or operator 

injecting CO2 for the primary purpose of long term storage obtain a Class VI permit with some 

special consideration for the fact that they are transitioning from a well not originally designed to 

meet Class VI requirements. The Director has the authority to determine at what point a Class VI 

permit is required for those projects that are transitioning from the primary purpose of EOR to 

long term storage of CO2. The final regulation provides a set of technical factors for the Director 

to evaluate in making this determination, at §144.19. EPA believes that this approach provides 

sufficient protection of USDWs when there is an increased risk to USDWs as compared to 

traditional Class II operations while allowing for site-specific flexibility. 

EPA is developing guidance on transitioning permits from Class II to Class VI. The guidance 

will assist Directors in determining whether an injection project should be transitioned from 

Class II where the primary purpose is oil and gas production to Class VI where the primary 

purpose is long-term storage of large volumes of CO2. The guidance describes the recommended 

methods the Director may use to evaluate changes in risk to USDWs from projects, and how the 

Director may determine whether a project should be regulated within the Class II or Class VI 

UIC program. This guidance will be available on EPA’s website at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. For more information, please 

see the discussion on transition of Class II wells in the preamble to the final GS rule. 

Letter ID: 0262 Comment ID: 22993 Letter Lines: 54 to 58 

Comment Code: 3140 2.1.4 Comments that the proposed geologic data requirements are too 

stringent 

Comment: Class II EOR wells to permanent CO2 storage wells. As proposed, the site geology 

requirements seem to be unduly burdensome without any real additional safety 

benefit to underground sources of drinking water. Site geology should be 

considered on a case by case basis to prevent the categorical elimination of 

sites which may be technically acceptable. 

Individual Response: EPA disagrees that the requirements at §146.82 are unnecessary and 

unduly burdensome and believes that a detailed geological site characterization is essential to 

evaluating the presence and adequacy of the various geologic features necessary to receive and 

confine injected CO2 for GS. The requirements for geologic site characterization are based on a 

long standing UIC regulatory framework developed to address specific risks to USDWs posed by 

injection. The Class VI GS requirements are tailored so that they are appropriate for the unique 

nature of injecting large volumes of CO2 into a variety of geological formations for long-term 

storage. 

EPA agrees that site characterization should be site-specific, particularly in light of the variety of 

geologic settings in which GS may be employed. EPA believes that, while there is a large 

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amount of required information, the owner or operator is given flexibility in determining what 

methods are used to demonstrate the suitability of a potential site. EPA envisions an ongoing 

dialogue between the Director and the owner or operator during the permitting process (as well 

as throughout the operation of the site). 

Letter ID: 0262 Comment ID: 22994 Letter Lines: 60 to 69 

Comment Code: 1000 1. General and Administrative Comments 

Comment: In an effort to reduce possible duplicate comments, we have reviewed the 

comments prepared by industry groups to which we belong and agree generally with 

the conclusions and approach of those comments. Those groups are as follows : 

Carbon Capture and Storage Alliance 

FutureGen Industrial Alliance 

Coal Utilization Research Council 

Gasification Technologies Council 

North American Caron Capture and Storage Association 

Western Business Roundtable 

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

responses to this comment letter and response to comments from the Carbon Capture and Storage 

Alliance, FutureGen Industrial Alliance, Coal Utilization Research Council, Gasification 

Technologies Council, North American Carbon Capture and Storage Association, and Western 

Business Roundtable 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: 0262 Comment ID: 22995 Letter Lines: 71 to 73 

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

Comment: We encourage EPA to consider seriously all of these comments which, if taken 

into consideration, could help create a more flexible, performance based Class 

VI program recognizing the characteristics of CO2 injections. 

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. 

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