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.
 

Ground Water Protection Council 

13308 N. MacArthur Blvd. 

Oklahoma City, OK 73142 

Tel: (405) 516-4972 

Fax: (405) 516-4973 

Dedicated to protecting our nation’s ground water. www.gwpc.org 

March 31, 2009 

Cynthia C. Dougherty, Director 

Office of Ground Water and Drinking Water 

USEPA 

Ariel Rios Building 

1200 Pennsylvania Avenue, N. W. 

Washington, DC 20460 

Dear Ms. Dougherty: 

On December 23, 2008, the Ground Water Protection Council (GWPC) signed a letter submitted 

by a Multi-Stakeholder Group (MSG) supporting the concept of creating a new class of UIC 

wells to manage the geologic sequestration of carbon dioxide. As part of that letter, the GWPC 

also supported the development of new subclass of the Class II program for the purposes of 

geologic sequestration of carbon dioxide in oil and gas reservoirs. 

One of the topics discussed in the December 23 letter was the need for a way to determine when 

a well permitted under the Class II program would cross a “bright line” for purposes of 

distinguishing between a well used primarily for enhanced recovery and one used primarily for 

geosequestration. It is our understanding that members of the MSG are submitting language to 

EPA suggesting the criteria under which wells would transition from Class II Enhanced 

Recovery to a new class or subclass of well for geosequestration. 

Since much of the proposal being submitted by the MSG is based upon the concepts expressed 

by the GWPC in its December 23, 2008 submission of recommendation to EPA concerning the 

proposed Class VI rule, we expect to support some portion or portions of the MSG language. 

Regardless, to insure the process of rule development proceeds at an appropriate pace, we 

recommend that EPA publish the language proposed by the MSG as part of its Notice of Data 

Availability (NODA). The GWPC will continue to work with the MSG on this issue and we 

look forward to submitting more detailed comments as the process moves forward. 

Respectfully, 

Mike Paque 

GWPC Executive Director 

cc: Robert F. Van Voorhees 

 Scott Anderson 
Letter ID: 0297 

Commenter: Michel Paque 

Organization: Ground Water Protection Council 

Letter ID: 0297 Comment ID: 29316 Letter Lines: 16 to 57 

Comment Code: 2044 1.5.2.2 Oppose Class VI/ Support Class II 

Comment: March 31, 2009 

Cynthia C. Dougherty, Director 

Office of Ground Water and Drinking Water 

USEPA 

Ariel Rios Building 

1200 Pennsylvania Avenue, N. W. 

Washington, DC 20460 

Dear Ms. Dougherty: 

On December 23, 2008, the Ground Water Protection Council (GWPC) signed a letter 

submitted by a Multi-Stakeholder Group (MSG) supporting the concept of creating 

a new class of UIC wells to manage the geologic sequestration of carbon dioxide. 

As part of that letter, the GWPC also supported the development of new subclass 

of the Class II program for the purposes of geologic sequestration of carbon 

dioxide in oil and gas reservoirs. 

One of the topics discussed in the December 23 letter was the need for a way to 

determine when a well permitted under the Class II program would cross a "bright 

line" for purposes of distinguishing between a well used primarily for enhanced 

recovery and one used primarily for geosequestration. It is our understanding 

that members of the MSG are submitting language to EPA suggesting the criteria 

under which wells would transition from Class II Enhanced Recovery to a new 

class or subclass of well for geosequestration. 

Since much of the proposal being submitted by the MSG is based upon the concepts 

expressed by the GWPC in its December 23, 2008 submission of recommendation to 

EPA concerning the proposed Class VI rule, we expect to support some portion or 

portions of the MSG language. Regardless, to insure the process of rule 

development proceeds at an appropriate pace, we recommend that EPA publish the 

language proposed by the MSG as part of its Notice of Data Availability (NODA). 

The GWPC will continue to work with the MSG on this issue and we look forward to 

submitting more detailed comments as the process moves forward. 

Respectfully, 

1
2

Mike Paque 

GWPC Executive Director 

cc: Robert F. Van Voorhees 

Scott Anderson 

Individual Response: EPA disagrees that wells injecting CO2 for the primary purpose of long 

term storage should be regulated under Class II requirements. The Agency believes that the 

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

risks than injection for the primary purpose of ER, 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 ER 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 ER projects. 

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. For more information, please see the discussion on 

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