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.- 0 W -Z66ib :10a~ 7 61



### MWD

METROPOLITAN WATER DISTRICT OF SOUTHERN CALIFORNIA

December 23, 2008

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

OSWER Docket

EPA Docket Center Mailcode : 2822T

Environmental Protection Agency

1200 Pennsylvania Ave

., NW Washington, DC 20460

Dear Environmental Protection Agency : 

## JAN 0 ,5 2009

Comments on Federal Requirements Under the Underground Injection Control Program for Carbon Dioxide (C02) Geologic Sequestration Wells

The Metropolitan Water District of Southern California (Metropolitan) is submitting comments on U .S

. Environmental Protection Agency's (EPA) proposed Federal requirements under the Safe Drinking Water Act (SDWA) for underground injection of C02 for the purpose of geologic sequestration (40 Federal Register 43492)

. This potential practice to mitigate the effects of greenhouse gas emissions raises the concern of potential contamination to underground sources of drinking water, particularly sole-source aquifers

. Other concerns include unproven technology to be used for injection wells, undefined water rights between states sharing a single underground

source of water, and unresolved long-term liability and financial responsibility for sequestration sites

. We appreciate EPA's efforts to address this urgent environmental concern and hope these
comments will assist in protecting the needs of drinking water utilities and their customers

.

Metropolitan is a regional water supply agency that provides supplemental water to nearly 18 million people throughout the southern California area

. Our two major sources of supply are the Colorado River and the California State Water Project utilizing water from the San Joaquin

- Sacramento River Bay Delta

. While Metropolitan does not own or operate groundwater wells as part of its water supply operation, approximately 37% of the annual retail demands for water in our service area depend on local and regional groundwater supplies

. Metropolitan and other agencies store surplus water in various groundwater basins throughout California for use during dry years

. Metropolitan and the agencies it serves depend heavily on the viability of these important groundwater basins to produce the balance of regional supply needs

.

We would specifically ask that EPA not implement any geologic sequestration pilot program in a groundwater basin that is the sole source of supply for an urban area

. Unproven commercial-scale geologic carbon sequestration technology may pose unintended impacts on groundwater basins and potentially compromise both water quality and water supply

.Docket ID Number EPA-HQ-OW-2008-0390

Page 2

December 24, 2008

The American Water Works Association (AWWA) has provided testimony and extensive written

comment of this proposed regulation

. The new class of injection well proposed under this rule specifically for injecting C02 into deep, underground geologic formations is a source of primary

concern for AWWA because of the potential contamination of underground sources of drinking

water, particularly sole source aquifers, and the unintended, possibly harmful, consequences

. Metropolitan shares this concern and joins with AWWA in the call to mitigate these concerns prior

to any final rulemaking

.

While Metropolitan and the drinking water industry support meaningful efforts to reduce greenhouse gas emissions, it is our hope that any gain in these reductions does not come at the

expense of vital drinking water supplies

. Metropolitan appreciates this opportunity to provide

comment and asks that EPA carefully consider these comments as well as those by AWWA and

other drinking water concerns

. Please contact me at (213) 217-5696 if you have any questions, or if

I can provide additional information

.

Very truly yours,

Mic Stewart, PhD Manager, Water Quality SectionLetter ID: 0279

Commenter: Mic Stewart Organization: Metropolitan Water Dist rict of Southern California

Letter ID: 0279 Comment ID: 24093 Letter Lines: 38 to 40

Comment Code: 1610 1.3.1 Risks to USDWs

Comment: 43492). This potential practice to miti gate the effects of greenhouse gas emissions raises the concern of potential contamination to underground sources of drinking water, particularly sole-sour ce aquifers. Other concerns include

Individual Response: The Agency agrees that drinking wa ter is an important resource to protect. The primary goal of the UIC Program under the SDWA is to protect USDWs from endangerment. Consistent with SDWA §1422, the UIC program provides that no injection shall

be authorized if it results in the movement of fluid containing any contaminant into USDWs, if the presence of that contaminant may cause a vi olation of any primary drinking water regulation or may adversely affect the health of persons as specified in §144.12.

The GS rule, as part of the UIC program regulations, continues the Program’s mandate under the SDWA of ensuring the protection of USDWs from endangerment. EPA expects that the tailored permitting, siting, construction, operation, monitoring, and post-injection site care requirements in the GS rule to prevent leakage from injection formations and protect USDWs.

The GS rule, at §146.82(a)(5) requir es prospective owners or opera tors to submit information on all USDWs within the AoR. EPA expects that this information will include identification of any sole source aquifers. The GS rule also requires operators to submit extensive information about the site, including the geologic characteristics of the inject ion and confining zones, to demonstrate that the injected CO2 will remain w ithin the target formation. The Director must consider this information when determining wh ether GS is acceptable at a given site. EPA expects that during this evaluation the Director will consider the potential impact of the GS project on any sole source aquifers.

Letter ID: 0279 Comment ID: 24094 Letter Lines: 40 to 43

Comment Code: 1310 1.1.2.4 Comments on other "out of scope" issues, e.g., pore space ownership

Comment Code: 5400 2.9 Proposed Financial Respons ibility and Long-Term Care Requirements

Comment: drinking water, particularly sole-sour ce aquifers. Other concerns include unproven technology to be used for inj ection wells, undefined water rights between states sharing a single underground source of water, and unresolved long-term liability and financial respons ibility for sequestration sites. We

1Individual Response: EPA clarifies that subsurface propert y rights, including water rights, are outside the scope of the GS rulemaking.

Under SDWA authority, owners or operators of injection well s must ensure protection of USDWs from endangerment and are subject to liab ility for enforcement under the Act. The final rule requires that an owner or operator must conduct monitoring as specified in the Directorapproved PISC and site closure plan following the cessation of injection until the owner or operator can demonstrate to the Director that th e geologic sequestration project no longer poses an endangerment to USDWs. For additional information about the PISC and site closure requirements, see the preamble to the final GS rule.

Once an owner or operator has met all regulator y 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 re quired under §146.85 will be released if it was not used. However, even if a site closure is a pproved under §146.93, an owner or operator may be held liable for regulatory noncompliance (inc luding 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 a pproved if the Direct or relied on erroneous information (e.g., erroneous modeling data) provi ded by the owner or operator when approving

site closure.

Additionally, an owner or operator may always be subject to any action the Administrator deems necessary to protect the health of persons under §1431 of the SD WA after site closure if there is unanticipated migration towards or into a US DW that causes or threatens imminent and substantial endangerment to public health. The action may include issuing administrative orders or commencing a civil action for appropriate relief. If the owner or operator fails to comply with the order, they may be subject to a civil penalt y for each day in which such violation occurs or failure to comply continues.

The Agency clarifies that Class VI well permits may be transferred to another owner or operator pursuant to §144.38 whereby generally all other regulatory re sponsibilities are transferred to that new owner and operator, which includes all poten tial liabilities associat ed with meeting the requirements of that permit. Please see further clar ification on the issue of long term liability in the preamble of the final rule.

Furthermore, after site closure an owner or ope rator may remain liable under tort and other remedies, or under other federal statutes includi ng, 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.

Letter ID: 0279 Comment ID: 24095 Letter Lines: 51 to 77

Comment Code: 1610 1.3.1 Risks to USDWs

2Comment: Project utilizing water from the San Joa quin Sacramento River Bay Delta. While Metropolitan does not own or operate groundw ater wells as part of its water supply operation, approximately 37% of the an nual retail demands for water in our service area depend on local and regional groundwater supplies. Metropolitan and other agencies store surplu s water in various groundw ater basins throughout California for use during dry years. Metr opolitan and the agencies it serves depend heavily on the viability of these important groundwater basins to produce the balance of regional supply needs.

We would specifically ask that EPA not implement any geologic sequestration pilot program in a groundwater basin that is the sole source of supply for an urban area. Unproven commercial-scale geologic carbon sequestration technology may pose unintended impacts on groundwater basins and potentially compromise both water quality and water supply.

The American Water Works Association (A WWA) has provided testimony and extensive written comment of this proposed regulat ion. The new class of injection well proposed under this rule specifically for injecting CO2 into deep, underground geologic formations is a source of primary concern for AWWA because of the potential contamination of underground sour ces of drinking wate r, particularly sole source aquifers, and the unintende d, possibly harmful, consequences. Metropolitan shares this concern and join s with AWWA in the call to mitigate these concerns prior to any final rulemaking.

While Metropolitan and the drinking water industry support meaningful efforts to reduce greenhouse gas emissions, it is our hope that any gain in these reductions does not come at the expens e of vital drinking water supplies.

Individual Response: The Agency agrees that drinking wa ter is an important resource to protect. The primary goal of the UIC Program under the SDWA is to protect USDWs from endangerment. Consistent with §1422, the UIC program provides that no injection shall be

authorized if it results in the movement of flui d containing any contaminant into USDWs, if the presence of that contaminant may cause a viola tion of any primary drinking water regulation or may adversely affect the health of persons as specified in §144.12.

The GS rule, as part of the UIC program regulations, continues the Program’s mandate under the SDWA of ensuring the protection of USDWs from endangerment. EPA expects that the tailored permitting, siting, construction, operation, monitoring, and post-injection site care requirements in the GS rule will prevent leakage from injection formations and protect USDWs.

The GS rule, at §146.82(a)(5) requir es prospective owners or opera tors to submit information on all USDWs within the AoR. EPA expects that this information will include identification of any sole source aquifers. The GS rule also requires operators to submit extensive information about the site, including the geologic characteristics of the inject ion and confining zones, to demonstrate that the injected CO2 will remain w ithin the target formation. The Director must

3consider this information when determining wh ether GS is acceptable at a given site. EPA expects that during this evaluation the Director will consider the potential impact of the GS project on any sole source aquifers.

EPA recognizes that injecting large volumes of CO2 for GS poses unique challenges and risks that, if not properly managed, could endanger drinking water s ources or have other adverse impacts. EPA agrees that caution is warranted a nd has, as a result, developed a new well class with requirements tailored to address the uni que challenges posed by GS and potential risks associated long-term injection of CO2. These re quirements include the ta ilored AoR delineation process per §146.84, monitoring that is appropriate to GS projects per §146.90, and extended post-injection s ite care per §146.93.

Letter ID: 0279 Comment ID: 24096 Letter Lines: 78 to 80

Comment Code: 1000 1. General and Administrative Comments

Comment: Metropolitan appreciate s this opportunity to provide comment and asks that EPA carefully consider these comments as we ll as those by AWWA and other drinking water concerns. Please contact me at ( 213) 217-5696 if you have any questions,

Individual Response: EPA acknowledges the comment. Pleas e see the remainder of EPA's responses to this comment le tter and AWWA’s comment for fu rther details. For additional information on EPA's final regulatory approach, pl ease see the final rule and preamble as well as the rulemaking docket.

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