### 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.

## ~

# Ameren Ameren Services

Enl';ronmtntal SeO';ce s

314554.2388 (Phone)

314554.4182 (Facsimile)

ppike@dmeren.com



### October 14, 2009

U

. S. Environmental Protection Agency

Water Docket

Mail Code 4101T

1200

. Pennsylvania Ave., NW

Washington, D

. C. 20460

Submitted on-line: www

. regulations.gov

Docket ID No. EPA-HQ-OW-2008-0390 One Ameren Plaza

1901 Chouteau Avenue

PO Box 66149

St. Louis, MO 63166-6149



### Re : Comments on Notice of Data Availability for Federal Requirements

Under the Underground Injection Control 

### role) Program for Carbon

Dioxide (C02) Geologic Sequestration (GS) Wells. 74 Fed. Reg. 44802

(Aug. 31. 2009)

To whom it may concern:

Ameren Corporation appreciates the opportunity to comment on the Notice of Data

Availability and Request for Comment ("NODA") relating to the proposed Federal

Requirements Under the Underground Injection Control ("VIC") Program for

Carbon Dioxide ("C02") Geologic Sequestration ( " GS " ) Wells. 74 Fed. Reg

. 44802 (Aug. 31, 2009). We submitted comments last December on EPA's

proposal to regulate C02 GS under the UIC program

. 

### Se e 73 Fed. Reg. 43492

(July 25, 2008).

Ameren Corporation ("Ameren") is based in SI. Louis, MO, and through its

operating companies serves 2.4 million electric and nearly one million natural gas

customers across a 64,OOO-square-mile area in Illinois and Missouri

. Ameren

companies ' net generating capacity is more than 16,400 megawatts. Our power

plants use a variety of fuels to generate electricity -p rineipally coal

, nuclear, hydro

and natural gas. In 2007, coal-fired generation accounted for 84 percent of our

total electric generation; 12 percent came from the company's single-unit nuclear

plant ; 2 percent from natural gas-fired units ; and 2 percent from hydroelectric

plants.

The Ameren family of companies operates through multiple subsidiaries in

different regulatory environments. In Missouri

, Ameren's utility subsidiary,

AmerenUE

, generates electricity, delivers natural gas and electricity and is

8 subsidiary of Amsren Corporation

### regulated by a state-appointed commission. Ameren is the parent company to three

Illinois utilities (collectively referred to as the Ameren Illinois Utilities) which

deliver natural gas and electricity and are regulated by a state-appointed

commission. Ameren also owns a number of non-rate-regulated subsidiaries,

including AmerenEnergy Resources, which is the holding company for some of

Ameren's non-rate-regulated power marketing and generating companies.

Regulation of GS under the UIC program will have a direct impact on Ameren,

particularly our fossil-fired facilities involved in the production of electricity and

we have a substantial interest in EPA's development of a realistic and costeffective UIC program for Class VI CO 2 GS wells. Ameren is a member of the

Utility Solid Waste Activities Group ("USWAG"), the Edison Electric Institute

("EEl"), and the Electric Power Research Institute ("EPRI)". We endorse the

comments filed by USWAG, EEl, and EPRI.

At the outset, Ameren applauds EPA's careful approach to the development of C02

GS regulations, including this most recent release of additional data. Because the

technology contemplated in the C02 GS proposal will not be commercially

deployed for many years, it is essential the Final Rule be flexible enough to

accommoclate clevelopments in information and technology related to carbon

sequestration. It 

### is critical that EPA develop a regulatory regime incorporating

performance-based standards in order to allow for site-tailored requirements that

will reflect the vast differences among various potential CO 2 GS sites.

We support EPA's suggestion to adopt a flexible waiver process to allow for C02

GS injection above and between underground sources of drinking water

("USDWs"). 74 Fed. Reg. at 44810. As stated in the NODA, EPA's original

proposal to define Class VI injection wells as those used for injection of CO 2

beneath the lowermost formation containing a USDW (73 Fed. Reg. at 43511)

would preclude injection of C02 into zones between and above USDWs, thereby

restricting or rendering impossible CO 2 GS sites in large areas of the country with

deep USDWs. 74 Fed. Reg. at 44808. The proposal would also prohibit CO 2

injection into many shallow formations such as coal seams and basalts. 73 Fed.

Reg. at 43512. As the NODA observes, a number of states have indicated that

regions with very deep and layered USDWs could not undertake C02 GS projects

because injectors could not comply with the proposed injection depth and well

construction requirements. 74 Fed. Reg. at 44809.

EPA addresses these concerns by the proposal set forth in the NODA to keep the

originall y proposed injection depth requirement but allow owners or operators to

apply for a site-specific waiver from those injection depth requirements upon

making a demonstration that such injection can be undertaken in a manner that

prevents the endangerment of public health from USDW contamination. 

### Id. at

44810. Ameren believes that such a flexible approach would ensure adequate

protection of USDWs while recognizing the vast geographic and topographic

differences between potential C02 GS sites throughout the country, allowing for

maximization of safe C02 storage capacity nationwide.

### While Arneren supports the flexible injection depth waiver proposal described

above, we urge EPA to consider requiring the inclusion of such a waiver provision

, rather than leaving the adoption of an injection depth waiver process to the

discretion of the individual UIC Program Directors. 

### Id. at 44811. While it is true

that deep USDWs do not exist in every state and that states without USDWs may

choose not to grant waivers, inclusion of a waiver provision would still leave UIC

Program Directors free to decline to grant any waivers where not necessary or

appropriate. See id. 

### C02 GS technology is rapidly developing; because this

experience with and information regarding this technology is growing rapidly, it is

prudent to structure a regulatory framework that is flexible enough to respond to

developments in the field

.

Ultimately, In drafting a final rule, EPA should strive to develop clear guidelines

for decision makers in evaluating waiver applications as well as the development

of a transparent and, to the extent possible, outcome-predictable process to provide

guidance for future applicants. In terms of the substantive requirements for waiver

applicants, the Agency should guard against the insertion of unnecessary

complexity and redundancy into the process that bring no corresponding increase

in protection of USDWs

.

Finally, as EPA acknowledges in the NODA, the Department of Energy ("DOE")

is developing and/or operating a number of C02 GS pilot projects throughout the

country

. These pilot projects share a common purpose: in EPA's own words, to

"help determine the best approaches for capturing and permanently storing" gases

such as C02, as well as to determine "the most suitable technologies, regulations,

and infrastructure needs for carbon capture, storage, and sequestration in different

parts of the country." 74 Fed. Reg. at 44805.

The NODA discusses three experimental GS projects as well as research being

conducted regarding the potential effects on USDWs in the highly unlikely event

that injected C02 migrates from the receiving formation. In evaluating the

techniques employed in these projects and the data produced, the Agency should

keep in mind that experimental projects are just that-experimental projects. The

techniques employed in any given setting may have much to offer the project, but

their successful employment in such a setting should not necessarily dictate their

universal application.

Arneren appreciates EPA's effort to broaden their base.of knowledge by drawing

on the experiences of these pilot projects prior to issuing a final rule. We are

concerned, however, that this NODA may be 

### premature, as it reflects data from

only a handful of the approximately thirty pilot projects affiliated with DOE. For

example, the Plains C02 Reduction Partnership ("PCOR") has only recently

completed and submitted information regarding their Phase II findings; these data,

as well as similar data from other pilot projects, are not reflected in the NODA.

This information will provide valuable insight into the advantages, limitations, and

challenges associated with C02 GS in different parts of the country. Arneren

urges EPA to consider the results of all DOE pilot projects prior to drafting a final

### C02 GS rule, and to make this information available for public review and

comment in a subsequent NODA prior to promulgation of a final rule

.

The NODA notes that many commenters on the proposed rule encouraged the

Agency to consider a more "comprehensive framework" for GS, addressing issues

arising under statutes other than SDWA, such as the Clean Air Act, the Resource

Conservation and Recovery Act, and the Comprehensive Environmental Response,

Compensation and Liability Act. It further states that the Agency "is currently

evaluating the need for a more comprehensive regulatory framework," and that if

the Agency "chooses to pursue" such a framework, it will seek public comment on

any proposal it develops. 74 Fed. Reg. at 44805

At the same time, while separate regulations for CCS are to some extent necessary,

Ameren encourages the Agency to avoid piecemeal regulation to the extent

possible and develop a single rule to address issues arising outside the SDW A

context. In the last year, the Agency has considered various provisions directly

impacting CCS projects under the Agency's proposed rule on Mandatory

Reporting of Greenhouse Gases (Docket ID No. EPA-HQ-ORA-2008-0508), 74



### Fed. Reg. 16448 (April 10, 2009), as well as its proposed changes to the

Renewable Fuel Standard (RFS) Program (Docket ID No. EPA-HQ-OAR-2oo5-



### 0161),74 Fed. Reg. 24904 (May 26, 2009), raising concerns that CCS may be

unnecessarily governed through a patchwork of separate provisions. A holistic

approach to CCS to the greatest extent possible is of critical importance to ensuring

efficient development and commercial deployment of CCS technologies.

Ameren appreciates the opportunity to comment on this new data and EPA ' s new

proposal for an injection depth waiver process and would welcome the opportunity

to work further with the Agency. Please feel free to contact me at 314-554-2388 or

prpike@ameren

. com with any questions.

Paul 

### R. Pike

Strategic Analyst-Environmental ServicesLetter ID: 0354

Commenter: Paul R. Pike

Organization: Ameren Corporation

Letter ID: 0354 Comment ID: 28071 Letter Lines: 68 to 75

Comment Code: 1000 1. General Comments on the Notice of Data Availability

Comment: At the outset, Ameren applauds EPA's careful approach to the development of CO2

as regulations, including this most recent release of additional data. Because

the technology contemplated in the CO2 GS proposal will not be commercially

deployed for many years, it is essential the Final Rule be flexible enough to

accommodate developments in information and technology related to carbon

sequestration. It is critical that EPA develop a regulatory regime incorporating

performance

‐ based standards in order to allow for site

‐ tailored requirements

that will reflect the vast differences among various potential CO2 as sites.

Individual Response: EPA believes that the final rule is based on the most recent GS

‐ related data,

information, and scientific research available. EPA intends to continue to collect data on GS and to

incorporate such data as it implements its adaptive approach to GS rulemaking to incorporate new

research, data, and information about GS. The Agency believes that an adaptive approach provides Class

VI owners or operators the flexibility to use and apply newly developed technologies for GS as they

become available in the future.

EPA agrees with the commenter that a site

‐ specific approach to permitting GS sites is important. The

final rule provides Class VI owners or operators the flexibility to select technologies appropriate for a

specific site and affords the Director flexibility to establish permit requirements on the basis of site

‐

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

‐ specific

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

Letter ID: 0354 Comment ID: 28072 Letter Lines: 77 to 99

Comment Code: 3210 3.2.1. Comments Generally in Support of the Approach

Comment: We support EPA's suggestion to adopt a flexible waiver process to allow for C02

as injection above and between underground sources of drinking water ("USDWs").

74 Fed. Reg. at 44810. As stated in the NODA, EPA's original proposal to define

Class VI injection wells as those used for injection of CO2 beneath thelowermost formation containing a USDW (73 Fed. Reg. at 43511) would preclude

injection of CO2 into zones between and above USDWs, thereby restricting or

rendering impossible C02 as sites in large areas of the country with deep USDWs.

74 Fed. Reg. at 44808. The proposal would also prohibit CO2 injection into many

shallow formations such as coal seams and basalts. 73 Fed. Reg. at 43512. As the

NODA observes, a number of states have indicated that regions with very deep and

layered USDWs could not undertake CO2as projects because injectors could not

comply with the proposed injection depth and well construction requirements. 74

Fed. Reg. at 44809.

EPA addresses these concerns by the proposal set forth in the NODA to keep the

originally proposed injection depth requirement but allow owners or operators to

apply for a site

‐ specific waiver from those injection depth requirements upon

making a demonstration that such injection can be undertaken in a manner that

prevents the endangerment of public health from USDW contamination. Id. at

44810. Ameren believes that such a flexible approach would ensure adequate

protection of USDWs while recognizing the vast geographic and topographic

differences between potential C02 as sites throughout the country, allowing for

maximization of safe CO2 storage capacity nationwide.

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

‐

specific flexibility in regulatory development and permitting as described in the NODA and Request for

Comment. The Agency acknowledges that there are some situations where injection into non

‐ USDW

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

GS rule at §146.95 establishes a process by which owners and operators can seek a waiver of the Class

VI injection depth requirements. The Agency believes the waiver approach: 1) responds to concerns

about local and regional geologic storage capacity limitations imposed by the proposed injection depth

requirements; 2) allows for a more site

‐ specific assessment of injection depth for GS projects; 3)

accommodates injection into different formation types; 4) allows for injection of CO2 for GS into non

‐

USDWs above and/or between USDWs when appropriate and where it can be demonstrated that

USDWs will be protected; and 5) responds to concerns about the use of aquifer exemptions for GS.

Finally, EPA's approach to addressing injection depth variability through a waiver process responds to

concerns about future drinking water resource availability and the need to ensure that high quality

water remains available in sufficient quantities to supply drinking water needs.

Letter ID: 0354 Comment ID: 28073 Letter Lines: 101 to 111

Comment Code: 3390 3.3.9. Comments Regarding State Discretion to Adopt the Waiver Approach

Comment: While Ameren supports the flexible injection depth waiver proposal describedabove, we urge EPA to consider requiring the inclusion of such a waiver

provision, rather than leaving the adoption of an injection depth waiver process

to the discretion of the individual UIC Program Directors. Id. at 44811. While

it is true that deep USDWs do not exist in every state and that states without

USDWs may choose not to grant waivers, inclusion of a waiver provision would

still leave UIC Program Directors free to decline to grant any waivers where not

necessary or appropriate. See id. CO2 GS technology is rapidly developing;

because this experience with and information regarding this technology is

growing rapidly, it is prudent to structure a regulatory framework that is

flexible enough to respond to developments in the field.

Individual Response: EPA clarifies that adoption of the waiver process remains at the discretion of

individual UIC programs. Therefore, States, Territories, and Tribes seeking primacy for Class VI wells are

not required to provide for injection depth waivers in their UIC regulations and may choose not to make

this process available to Class VI wells under their jurisdiction. Although some commenters asked EPA to

require that waivers be applied nationally, the Agency believes that the decision about whether a waiver

program is appropriate in a specific State, Tribe, or Territory should be made by each program. This

approach allows flexibility for individual program Directors to determine the appropriateness of allowing

for waivers based on regional or state

‐ specific conditions, such as the predominant geologic settings

anticipated to be used for GS or other land uses in the state while ensuring maximum protection of

USDWs. The final approach for injection depth waivers represents minimum Federal requirements. UIC

program Directors may adopt GS requirements that do not allow injection above or between USDWs if

they determine this to be appropriate (for conditions in their State, Territory, Tribe, or Region) and

protective.

EPA recognizes that GS technologies are rapidly developing. For this reason, the Agency is adopting an

adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects,

including information on any Class VI wells granted a waiver of the injection depth requirements, to

determine whether the appropriate amount and types of information and appropriate documentation

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

Letter ID: 0354 Comment ID: 28074 Letter Lines: 113 to 119

Comment Code: 3240 3.2.4. Comments that the Approach Requests Too Much Data (seeking comment)

Comment: Ultimately, in drafting a final rule, EPA should strive to develop clear

guidelines for decision makers in evaluating waiver applications as well as the

development of a transparent and, to the extent possible, outcome

‐ predictable

process to provide guidance for future applicants. In terms of the substantive

requirements for waiver applicants, the Agency should guard against theinsertion of unnecessary complexity and redundancy into the process that bring

no corresponding increase in protection of USDWs.

Individual Response: EPA believes that the information required to obtain a waiver is necessary to

ensure that the owner or operator collects information and demonstrates to the Director that the

injection zone is suitable for GS, is confined by confining units above and below the injection zone, and

that well construction, operation, and monitoring are tailored for the site and take into consideration

the presence of USDWs above and below the injection zone. Because USDW protection is the priority of

the GS rule, owners or operators seeking waivers must provide a supplemental report (the GS Class VI

injection depth waiver application report), referenced at §146.82(d) and outlined at §146.95(a), with

their Class VI permit applications. This report, suggested by commenters, is designed to ensure that all

waiver information is discrete (from the permit application) and can be made available to the Director,

PWSS Directors, and the public when the waiver is publicly noticed with the draft Class VI permit

application. The Agency believes that this report and requirements at §146.95 are complementary and

not redundant of the Class VI permit application requirements. Furthermore, to eliminate concerns

about duplication or redundancy, the requirements at §146.82(d) clarify that the supplemental report is

not part of the permit application.

The final GS rule also contains a clear and transparent review process. Section 146.95(b) establishes

considerations that the UIC Director must assess when evaluating a waiver application to ensure that

USDW protection, site

‐ specific drinking water resource issues, and the use and impact of GS

technologies are considered and documented. Section 146.95(c) requires the Director to give public

notice, as part of the permit application process, including notice that a waiver application has been

submitted. If the permitting authority receives comments on the injection depth waiver during the

public comment period for both the waiver and the permit application, the Director in consultation with

the Regional Administrator, must evaluate comments prior to providing a recommendation to the

Regional Administrator regarding a waiver and issuing the Class VI permit.

EPA is developing guidance on the injection depth waiver process. The guidance describes the

recommended approach an owner or operator may follow when submitting a waiver application,

processing waiver applications by the UIC and PWSS Program Directors, and additional considerations

that may apply to projects that have been issued waivers. This guidance will be available on EPA’s

website at water.epa.gov/type/groundwater/uic/wells_sequestration.cfm.

Letter ID: 0354 Comment ID: 28075 Letter Lines: 121 to 150

Comment Code: 2100 2.1 DOE Regional Carbon Sequestration Partnership Projects

Comment: Finally, as EPA acknowledges in the NODA, the Department of Energy ("DOE") is

developing and/or operating a number of CO2 GS pilot projects throughout thecountry. These pilot projects share a common purpose: in EPA's own words, to

"help determine the best approaches for capturing and permanently storing" gases

such as CO2, as well as to determine "the most suitable technologies,

regulations, and infrastructure needs for carbon capture, storage, and

sequestration in different parts of the country." 74 Fed. Reg. at 44805.

The NODA discusses three experimental GS projects as well as research being

conducted regarding the potential effects on USDWs in the highly unlikely event

that injected C02 migrates from the receiving formation. In evaluating the

techniques employed in these projects and the data produced, the Agency should

keep in mind that experimental projects are just that

‐ experimental projects. The

techniques employed in any given setting may have much to offer the project, but

their successful employment in such a setting should not necessarily dictate

their universal application.

Ameren appreciates EPA's effort to broaden their base of knowledge by drawing on

the experiences of these pilot projects prior to issuing a final rule. We are

concerned, however, that this NODA may be premature, as it reflects data from

only a handful of the approximately thirty pilot projects affiliated with DOE.

For example, the Plains CO2 Reduction Partnership ("PCOR")") has only recently

completed and submitted information regarding their Phase II findings; these

data, as well as similar data from other pilot projects, are not reflected in

the NODA. This information will provide valuable insight into the advantages,

limitations, and challenges associated with C02 OS in different parts of the

country. Ameren urges EPA to consider the results of all DOE pilot projects

prior to drafting a final C02 GS rule, and to make this information available

for public review and comment in a subsequent NODA prior to promulgation of a

final rule.

Individual Response: EPA believes that the regional partnerships provide important information on GS,

but recognizes that use of a technology in a RCSP project does not make a technology valid for all

applications. Each project will be unique and the final rule provides for site

‐ specific approaches to

ensure that appropriate construction, operation, and monitoring is performed at each site. However, by

testing multiple technologies, the pilot sites provide valuable data that demonstrate whether or not

these technologies are viable and informed the final GS rule.

EPA intends to continue monitoring these projects for useful information, but EPA also believes it is

necessary not to delay the regulations as a common nationwide approach is needed to oversee this

growing activity. EPA intends to use an adaptive approach to the GS regulation. EPA plans, every six

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

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

modifications to the requirements are appropriate or necessary.Letter ID: 0354 Comment ID: 28076 Letter Lines: 152 to 172

Comment Code: 1100 1.1 Comments on the Comprehensive Approach

Comment: The NODA notes that many commenters on the proposed rule encouraged the Agency

to consider a more "comprehensive framework" for GS, addressing issues arising

under statutes other than SDWA, such as the Clean Air Act, the Resource

Conservation and Recovery Act, and the Comprehensive Environmental Response,

Compensation and Liability Act. It further states that the Agency "is currently

evaluating the need for a more comprehensive regulatory framework," and that if

the Agency "chooses to pursue" such a framework, it will seek public comment on

any proposal it develops. 74 Fed. Reg. at 44805

At the same time, while separate regulations for CCS are to some extent

necessary, Ameren encourages the Agency to avoid piecemeal regulation to the

extent possible and develop a single rule to address issues arising outside the

SDWA context. In the last year, the Agency has considered various provisions

directly impacting CCS projects under the Agency's proposed rule on Mandatory

Reporting of Greenhouse Gases (Docket ID No. EPA

‐ HQ

‐ ORA

‐ 2008

‐ 0508), 74 Fed. Reg.

16448 (April 10, 2009), as well as its proposed changes to the Renewable Fuel

Standard (RFS) Program (Docket ID No. EPA

‐ HQ

‐ OAR

‐ 20050161), 74 Fed. Reg. 24904

(May 26, 2009), raising concerns that CCS may be unnecessarily governed through

a patchwork of separate provisions. A holistic approach to CCS to the greatest

extent possible is of critical importance to ensuring efficient development and

commercial deployment of CCS technologies.

Individual Response: EPA acknowledges that GS falls within the broader context of CCS and the need for

regulatory clarity to ensure that USDWs are protected from endangerment. In developing the final GS

rule, the Office of Water coordinated with other Agency program offices and across federal agencies

(e.g., with the Department of Energy; United States Geological Survey; Bureau of Ocean Energy

Management, Regulation, and Enforcement, formerly the Minerals Management Service; Bureau of

Land Management). The Agency continues to evaluate areas of potential applicability of other Federal

environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and

Recovery Act; the Comprehensive Environmental Response, Compensation, and Liability Act; and the

Marine Protection, Research and Sanctuaries Act to various aspects of GS and CCS. The Agency will

continue to coordinate on GS and CCS related issues to minimize redundancy and maximize efficiencies

for owners or operators. For additional information, please see the discussion entitled "How Does This

Rulemaking Relate to Other Federal Authorities and GS and CCS Activities?" in the preamble to the final

GS rule.