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.December 23, 2008

Cynthia C. Dougherty

Director Office of Ground Water and Drinking Water U. S. Environmental Protection Agency 1200 Pennsylvania Ave., NW. Washington, DC 20460

Dear Director Dougherty:

The organizations identified below submit these comments and recommendations to the Environmental Protection Agency (EPA) in res ponse to the proposed rule for geologic sequestration of carbon dioxide under the Sa fe Drinking Water Act (SDWA). "Federal Requirements Under the Underground Injection Cont rol (UIC) Program for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells", 73 Fed. Re g. 43491-541 (July 25, 2008), Docket ID No. EPA– HQ–OW–2008–0390. We appreciated the extensi on of the public comment period that was granted by Assistant Administrator Benjamin Grumbles, announced in the Federal Register on November 21 and confirmed in your letter of November 24. The organizations submitting these recommendations represent a broad array of interests in the issues associated with this rulemaking and many of us have been discussing these interests and issues in an effort to reach consensus or at

least narrow our differences. We used this extensi on period to continue efforts toward developing recommendations reflecting common views on a number of the major issues in this rulemaking on which EPA expressly requested comment and several other issues. We share your hope that these comments and recommendations will help the Agency develop a rule that will allow the technology to be permitted under an appropriate injection cl ass while also ensuring protection of underground sources of drinking water as well as human health and the environment.

EPA has noted that the proposed rules do not ad dress "accounting or certification for greenhouse gas (GHG) reductions." 73 Fed. Reg. 43492, 4349 5 (July 25, 2008). By the same token, the consensus recommendations presented in this letter are solely for the purpose of GS regulation under the Safe Drinking Water Act to protect USDWs and not for the purpose of addressing verification requirements for carbon credits.

Enhanced recovery of oil or natural gas and geologic sequestration of CO 2

EPA’s Proposal would continue to regulate and permit injection of CO 2 for EOR/EGR purposes as Class II injection “as long as any production is occurring.” EPA has asked for comment on the merits of this approach “since owners or operato rs of some Class II EOR/EGR wells may wish to use wells for the purposes of production and GS pr ior to the field being completely depleted.” 73 Fed. Reg. at 43502. We recommend that the rule s be clarified to provide more certainty about the applicability of Class II requirements where GS of CO2 occurs in connection with EOR/EGR activities. Specifically, the UIC rules should provid e a “bright line” definition as to the applicableCynthia C. Dougherty December 23, 2008 Page 2

class of wells where CO2 injection for EOR/EGR production and for GS occur in tandem. We recommend the following language to accomplish that objective:

§ 144.6, 144.80 and 146.5, and Classification of injection wells.

Injection wells are classified as follows:

* * * (b) Class II. Wells which inject fluids:

(1) Which are brought to the surface in c onnection with conventional oil or natural gas production and may be commingled with waste waters from gas plants which are an integral part of production operations, unless those waters are classified as a hazardous waste at the time of injection.

(2) For enhanced recovery of oil or natural gas;

(3) For storage of hydrocarbons which are liquid at standard temperature and

pressure;

(4) For enhanced recovery of oil or natural gas where geologic sequestration is occurring during or in c onnection with enhanced recovery of oil or natural gas provided (i) there is reasonable expectation of more than insignificant future production volumes or rates as a result of carbon dioxide injection and (ii) operating pressures are no higher than reasonably necessary to produce such volumes or rates ;

* * * (f) Class VI. Wells injecting a carbon di oxide stream for geologic sequestration except those wells described in subsection (b)(4) of this section or otherwise

excluded from this Class

. 1 /

The undersigned have agreed that proposed lang uage describing wells in classification (b)(4) establishes a “bright line” definition for wells that inject CO2 for EOR/EGR and GS and, consistent with EPA’s intent, should remain in Class II and be subject to the current requirements of Class II. We have also agreed that the wells used for GS in oil and gas reservoirs that do not meet the criteria of (b)(4) should be subject to additional requirements. We have tentatively defined such wells as wells used “for geologic sequestration in oil and gas formations and where the criteria of paragraph (b)(4) are not met.” But we have not yet attempted to define what specific

1/ Please note that well classification for geologic sequestration in certain formations is a matter still under

discussion within the multi-stakeholde r group and may be addressed further in future recommendations from the group. In the mean time individual participants in these discussions will be expressing views on this and other issues with an openness to revising th eir views if a consensus can be reached.Cynthia C. Dougherty December 23, 2008 Page 3

requirements should apply to these wells. We ar e committed to working toward agreement on those requirements (probably within a Class II context) and submitting the results of that effort to EPA by February 28, 2009 for your consideration.

Injection Pressure Limitations

We are concerned about three aspects of proposed section 146.88(a), governing injection pressure limitations. First, it “restricts” fractures in th e injection zone “except during stimulation” rather than focusing on maintaining the integrity of the confining zone, which is what really matters for protecting USDWs. Second, it fails to refer specifi cally to the full range of potential geomechanical failure modes potentially posed by operations at a particular site. Third, the type of geomechanical risk that is addressed (initiation or propagation of fr actures), is dealt with in a potentially arbitrary fashion (the 90% of fracture pressure limit), wh ich may not be appropriate in all cases.

Our recommended language addresses these concerns by focusing on maintaining the integrity of the confining zone and including tensile failure and shear failure as transmissivity concerns. It calls for additional geomechanical studies of tensile fa ilure and shear failure only “where appropriate”

because there will be locations where experience or existing in formation will provide sufficient evidence to avoid the need for additional studies. The need for conducting additional tests and for determining which tests would be acceptable is left to the Director’s discretion.

The owner or operator must comply wi th a maximum injection pressure limit approved by the Director and specified in the permit. In approving a maximum injection pressure limit, the Director shall consider the results of well tests and, where appropriate, geomechanical or other studies that assess the risks of tensile

failure and shear failure. The Director sha ll approve limits that, with a reasonable degree of certainty, will avoid initiation or propagation of fractures in the confining

zone or cause otherwise non-transmissive fa ults transecting the confining zone to become transmissive. In no case may injection pressure cause movement of injection or formation fluids in a manner pr ohibited by 40 CFR Part 144.12(a).

Closure Standard

We believe there are three problems with the closur e standard in proposed section 146.93(b). First, the presumption that monitoring should continue for 50 years is unnecessary and counterproductive. A straight performance standard is preferable to this or any other fixed time period because it provides a clearer standard and an incentive to maximize the understanding of site and project performance and as such is more protective of USDWs. Second, the proposal requires a showing that the CO2 plume has “stabilized”, which is undefined. Cessation of plume movement is not necessarily essential to show that a project poses no threat of endangerment to USDWs— plumes that are still moving may, nonetheless, remain contained. Instead, it is more protective to show that the plume is not expected to encounter a leakage pathway. Third, the required showingCynthia C. Dougherty December 23, 2008 Page 4

that “no additional monitoring is needed” does not provide guidance regarding how an operator is to show that no additional monitoring is needed. The proposal below provides specific guidance on what the operator must show.

We recommend the standard in the proposed al ternative language for section 146.93(b) below

because it sets forth detailed criter ia, all of which must be satisfied, to demonstrate that the site does not pose an endangerment to USDWs. The specifi c criteria listed in our proposal will serve to provide the Director with the requisite informati on to make the appropriate determination. The advantage of this approach is that it establishe s clear criteria that an operator must demonstrate before obtaining site closure based upon particular site characteristics and is, therefore, reasonably applicable to any storage site as opposed to a standa rd based upon a fixed-duration. Furthermore, it is more stringent than a purely discretionary approach because it establishes specific criteria that must be shown before site closure may be granted. We believe this language, which is an extension of work done by the World Resources Institute and the Ground Water Protection Council, avoids the noted shortcomings and provides stronger protection for USDWs.

146.93 (b) The owner or operator shall monitor the site following the cessation of injection.

(1) The owner or operator shall continue to conduct monitoring as specified in the Director-approved post- injection site care and site clo sure plan until closure is authorized pursuant to 146.93(b)(3).

(2) The owner or operator can request and demonstrate to the satisfaction of the Director that the post-injection site care and site closure plan should be revised to reduce the frequency of monitoring.

(3) Prior to authorization for site closure, the owner or operator must demonstrate to the Director, based on m onitoring, other site-specific data, and modeling that is reasonably consistent with site performance, that no additional monitoring is needed to assure that the ge ologic sequestration project does not and is not expected to pose an endangerment to USDWs. The Director shall approve closure if the owner or operator demonstr ates, based on the current understanding of the site, including monitoring data and/or modeling, all of the following: (i) the estimated magnitude and extent of the proj ect footprint (CO2 plume and the area of elevated pressure) ; (ii) the estimated locati on of the detectable CO 2 plume; (iii) that there is no significant leakage of either CO2 or displaced formation fluids that is endangering USDWs; (iv) that the injected or displaced fluids are not expected to migrate in the future in a manner that en counters a potential leakage pathway into a USDW; (v) that the injection wells at the site completed into or through the injection zone or confining zone are plugged and abandoned in accordance with theseCynthia C. Dougherty December 23, 2008 Page 5

requirements; and (vi) any remaining project monitoring wells at the site are being managed by a person and in a manner acceptable to the Director.

Need for adequate implementation resources

Although not directly addressed in the EPA proposal , the need for adequate resources to implement the regulatory program for geologic sequestration at both the federal and state levels is a major

consideration and one that EPA should be addre ssing both internally and in its discussions with Congress. The annual national budget for the UIC program (approximately $11 million) has remained static for many years, while UIC agen cies have been asked to take on additional responsibilities. Furthermore, inflation of salaries and other expenses has eroded the buying power of the unchanging UIC budget. If state and regi onal agencies are asked to take on the additional

workload of CO 2 injection, while ensuring careful scient ific review as well as an expeditious processing time, they will require additional trained staff and other resources.

If the nation is serious about controlling CO 2 through underground injection, significant additional

resources will need to be made available to hire new permitting staff and field inspectors. Those new staff, along with the existing cadre of UIC staff an d managers, must be trained in subjects that will enable them to make prudent permitting, mana gement, and oversight decisions. As momentum grows to begin sequestering CO 2 underground, EPA and states will need to develop new regulatory requirements for CO 2 wells and prepare to review applications and make permitting decisions. Failure to provide sufficient resources will likely cr eate permitting backlogs, resulting in a bottleneck in the overall geologic sequestration effort.

The Ground Water Protection Council (GWPC) estima ted in 2004 that an annual funding increase to $56 million would be needed just to meet the needs of the existi ng UIC program at the state level even without the addition of geolog ic sequestration project permitting. 2 / GWPC has further

estimated that EPA will n eed to provide funding at a level of $100 million annually to meet the needs for the full UIC program, including the regulation of geologic sequestration.

Conclusion

We greatly appreciate the extension of the public comment period, as it has allowed us to make substantial progress in expanding our shared understanding on the releva nt issues and to reach significant agreement on how these issues can be a ddressed and resolved by EPA. The undersigned submit these recommendations with the request that the recommendations be considered as a whole because the recommendations were developed in combination to accurately reflect our shared understanding. In addition, we are committed to c ontinuing our discussions and to inviting others to participate with an objective of developing additional specific recommendations for improvement of a final rule that could be adopted by your sc heduled date in late 2010 or early 2011, including development of the requirements to be applied to o il and gas reservoir geologic sequestration that is

2/ GWPC, Class V Resource Needs Su rvey, Summary (September 2004).Cynthia C. Dougherty December 23, 2008 Page 6

not conducted in conjunction with enhanced oil an d gas production operations. We will be working toward submission of additional recommendations by February 28, 2009.

Sincerely,

Kyle Isakower Director, of Policy Analysis

American Petroleum Institute

Craig Walters General Manager, Enhanced Oil Recovery Anadarko Petroleum Corporation

Brian Williams Global CO2 Storage Manager BP Alternative Energy North America Inc.

Karen St. John Director Regulatory Affairs

BP America Inc.Cynthia C. Dougherty December 23, 2008 Page 7

Robert F. Van Voorhees Counsel to the Carbon Sequestration Council (CCS Contact Group)

Kurt Waltzer Carbon Storage Development Coordinator

Clean Air Task Force

Jeff W. Sheets

Senior Vice President Planning & Strategy ConocoPhillips

Ronald T. Evans Senior Vice President, Reservoir Engineering Denbury Resources Inc.

William L. Fang Deputy General Counsel

Edison Electric InstituteCynthia C. Dougherty December 23, 2008 Page 8

Scott Anderson Senior Policy Advisor, Climate and Air Program

Environmental Defense Fund

Michel Paque

Executive Director

Ground Water Protection Council

Al Collins Senior Director, Regulatory Affairs Occidental Petroleum Corporation

Karl R. Moor

Vice President and Associate General Counsel Southern Company

Darrick W. Eugene

General Counsel Texas Carbon Capture & Storage Association

cc: Ben Grumbles

Steve Heare Ann CodringtonLetter ID: 0191 Commenter: Kyle Isakower Organization: American Petroleum Institute

Letter ID: 0191 Comment ID: 23878 Letter Lines: 55 to 122

Comment Code: 1240 1.1.1.3 Suggested changes/ed its to rule language

Comment Code: 2046 1.5.2.3 Continuing to classify CO2 in jection for EOR/EGR as Class II/ dividing line between Class II and Class VI (seeking comment)

Comment: Enhanced recovery of oil or natural gas and geologic sequestration of CO2

EPA’s Proposal would continue to regul ate and permit injection of CO2 for EOR/EGR purposes as Class II injection "as long as any produc tion is occurring."

EPA has asked for comment on the merits of this approach "since owners or operators of some Class II EOR/EGR wells may wish to use wells for the purposes of production and GS prior to the field being completely depleted." 73 Fed. Reg.

at 43502. We recommend that the rules be clarified to provide more certainty about the applicability of Class II requirements where GS of CO2 occurs in

connection with EOR/EGR activ ities. Specifically, the UI C rules should provide a "bright line" definition as to the applicab le class of wells wh ere CO2 injection for EOR/EGR production and for GS occur in tandem. We recommend the following language to accomplish that objective:

[In the paragraphs below, the text in all CAPS denotes added text.]

§ 144.6, 144.80 and 146.5, and Classificati on of injection wells.

Injection wells are classified as follows:

* * *

(b) Class II. Wells which inject fluids:

(1) Which are brought to the surface in connection with conventional oil or natural gas production and may be co mmingled with waste waters from gas plants which are an integral part of production operations, unless

those waters are classified as a hazardous waste at the time of injection.

(2) For enhanced recovery of oil or natural gas;

(3) For storage of hydrocarbons which ar e liquid at standard temperature and pressure;

1(4) FOR ENHANCED RECOVERY OF OIL OR NATURAL GAS WHERE GEOLOGIC SEQUESTRATION IS OCCURRING DURING OR IN CONNECTION WITH ENHANCED

RECOVERY OF OIL OR NATURAL GAS PROVIDED (I) THERE IS REASONABLE

EXPECTATION OF MORE THAN INSIGNI FICANT FUTURE PRODUCTION VOLUMES

OR

RATES AS A RESULT OF CARBON DIOXI DE INJECTION AND (II) OPERATING

PRESSURES ARE NO HIGHER THAN REASONABL Y NECESSARY TO PRODUCE SUCH VOLUMES OR RATES;

* * *

(F) CLASS VI. WELLS INJECTING A CA RBON DIOXIDE STREAM FOR GEOLOGIC SEQUESTRATION EXCEPT THOSE WELLS DESCRIBED IN SUBSECTION (B)(4) OF

THIS SECTION OR OTHERWISE EXCLUDED FROM THIS CLASS.[FN1/]

[FN1/: Please note that well classifica tion for geologic sequestration in

certain formations is a matter still under discussion within the multistakeholder group and may be addressed fu rther in future recommendations from the group. In the mean time individual partic ipants in these di scussions will be expressing views on this and other issues with an openness to revising their views if a consensus can be reached.]

The undersigned have agreed that propos ed language describing wells in classification (b)(4) establishes a "bri ght line" definition for wells that inject CO2 for EOR/EGR and GS and, consistent with EPA’s intent, should remain in Class II and be subject to the current requirements of Class II. We have also agreed that the wells used for GS in oil and gas reservoirs that do not meet the criteria of (b)(4) should be subject to additional requirements. We have tentatively defined such wells as wells us ed "for geologic sequ estration in oil and gas formations and where the criteria of paragraph (b)(4) are not met." But we have not yet attempted to define wh at specific requirements should apply to these wells. We are committed to working toward agreement on those requirements (probably within a Class II context) and submitting the results of that effort to EPA by February 28, 2009 for your consideration.

Individual Response: EPA did not make the suggested change . The Agency disagrees that wells injecting CO2 for the primary purpose of long te rm storage should be regulated under Class II requirements. The Agency believes that the natu re and risks of CO2 injection for the primary purpose of long term storage poses different risks than injection for the primary purpose of EOR, and therefore has developed new Class VI regul ations 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.

2Based on its evaluation of all public comment s and input on the proposed rule and NODA and Request for Comment EPA has made many revisions to the GS Rule. See the final rule and preamble for further discussion on EPA's final appr oach to transitioning from Class II to Class

VI.

Letter ID: 0191 Comment ID: 23879 Letter Lines: 124 to 155

Comment Code: 1240 1.1.1.3 Suggested changes/ed its to rule language

Comment Code: 4110 2.4.1.1 Injection pressure limitations

Comment: Injection Pressure Limitations

We are concerned about three aspects of proposed section 146.88(a), governing injection pressure limitations. First, it "restricts" fractures in the injection zone "except during stimulation" rath er than focusing on maintaining the integrity of the confining zone, which is what really matters for protecting USDWs. Second, it fails to refer specifi cally to the full ra nge of potential geomechanical failure modes potentially posed by operations at a particular site. Third, the type of geomechanical ri sk that is addressed (initiation or propagation of fractures), is dealt with in a potentially arbitrary fashion (the 90% of fracture pressure limit), which may not be appropriate in all cases.

Our recommended language addresses these co ncerns by focusing on maintaining the integrity of the confining zone and incl uding tensile failure and shear failure as transmissivity concerns. It calls fo r additional geomechanical studies of

tensile failure and shear failu re only "where appropriate" because there will be locations where experience or existing information will provide sufficient

evidence to avoid the need for additiona l studies. The need for conducting additional tests and for determining which te sts would be acceptab le is left to

the Director’s discretion.

The owner or operator must comply w ith a maximum injection pressure limit approved by the Director and speci fied in the permit. In approving a maximum injection pressure limit, the Director shall consider the results of well tests and, where appr opriate, geomechanical or other

studies that assess the risks of tens ile failure and shear failure. The Director shall approve limits that , with a reasona ble degree of certainty, will avoid initiation or pr opagation of fractures in the confining zone or cause otherwise n on-transmissive faults transecting the confining zone to become tran smissive. In no case may injection pressure cause movement of injectio n or formation fluids in a manner prohibited by 40 CFR Part 144.12(a).

Individual Response: EPA notes that because determination of the injection pressure limit is based on the fracture pressure of th e injection zone, the limit is si te-specific and not arbitrary and is appropriate to protect USDW s from endangerment. EPA emphasi zes that injection pressure

3limits are important to protect ag ainst fracturing of the confining zone, and that the requirement at §146.88(a) that the pressure in the injecti on zone not exceed 90 pe rcent of the fracture pressure provides a margin of safety in the well operation and protects USDWs from endangerment. If the Director determines, based on a review of the information collected as part of site characterization, that a lo wer injection pressure limitation is appropriate, the Director has the authority to set a lower limit in the operati ng permit than the limit established in the rule.

EPA notes that during the site characterization pr ocess, owners or operators must submit data about the geology of the site, as specified at §146.82(a), includ ing data on known or suspected faults and fractures and geomechanical informati on on fractures, stress, du ctility, rock strength, and in situ fluid pressures w ithin the confining zone. The Di rector will use these data to determine appropriate limits on injection.

In response to the concern about reopening of faults at lower pressures than 90 percent of fracture pressure, EPA believes that the requireme nt for the owner or operator to submit data on known or suspected faults and fractures and inform ation on the seismic history of the site will inform the determination of an appropriate pressu re limitation in the permit. Any sites with the potential for reopening or reactivation of faults or unacceptable seismic risk that could otherwise interfere with containment will not be permitted as GS sites.

EPA is developing guidance on site characterization for GS projects to assist owners or operators in meeting the requirements of §146.82 and to assist directors in evaluating permit applications. The guidance will describe recommended approach es for characterizing the regional geology and hydrogeology of a proposed site and performing the necessary geochemical, geomechanical, and geophysical analyses of the injection and confin ing zone. EPA is also developing guidance for primacy agencies that will include recommended a pproaches for evaluating owner or operatorsubmitted data in setting permit conditions. The gu idance will be available on EPA's web site, at http://water.epa.gov/type/groundwater /uic/wells_sequestration.cfm.

Letter ID: 0191 Comment ID: 23880 Letter Lines: 157 to 164

Comment Code: 5240 2.8.2.2 Post injection timeframe (seeking comment)

Comment: Closure Standard

We believe there are three problems with the closure standard in proposed section 146.93(b). First, the presumption th at monitoring should continue for 50 years is unnecessary and counterproductive. A straight performance standard is preferable to this or any other fixed ti me period because it provides a clearer

standard and an incentive to maximize the understanding of site and project performance and as such is more prot ective of USDWs. S econd, the proposal

Individual Response: The post-injection site care require ments in the final GS rule, §146.93(b), incorporate a combination of a 50-year default po st-injection site care ti meframe, in conjunction with a performance standard, for Class VI wells . The GS rule offers owners or operators flexibility regarding the duration of the PISC timeframe by: (1) allowing the Director discretion

4to shorten or lengthen the PISC timeframe during the post-injecti on period based on site-specific data, pursuant to requirements at §146.93(b); or (2) affording the Director discretion to allow a Class VI well owner or operator to demons trate, during the permitting process based on substantial data, that an alternative PISC tim eframe may be appropria te if it ensures nonendangerment of USDWs pursuant to requirements at §146.93(c).

EPA believes however, that to ensure USDW protection from enda ngerment, a default timeframe for post-injection site care will be necessary in al l but a limited number of cases. This default 50 year post-injection site care ti meframe represents a reasonable and protective monitoring period based on a review of research studies, industr y reports, and existing environmental programs, and evaluation of public comments.

EPA believes that a default post-injection site car e timeframe of 50 years, with flexibility to adjust the timeframe for a limited number of GS projects during the permitting process where

substantial data exists to demonstrate that an alternative timeframe would be protective of USDWs, or based on data collected during the PISC period, is appropriate to address the range of sites where GS is anticipated to occur, to ac commodate site-specific circumstances and various geologic conditions, and addre sses commenters’ concerns, wh ile ensuring USDW protection. Both approaches will utilize si te-specific data, and be based on pressure monitoring and USDW impacts. EPA expects that the Director will c onsider the types of information the commenter describes in determining whether the plume a nd pressure front no longer pose a risk of endangerment to USDWs and post-injection site care monitoring may be discontinued.

EPA is developing guidance to assist owners or operators in evaluating well plugging, postinjection site care, and site closure requirements of §146.92 and §146.93. Additionally, the guidance will assist Directors in evaluating propo sed well plugging plans a nd post-injection site care and site closure plans under §146.92 a nd §146.93. The guidance describes recommended approaches for how an owner or operator coul d plug injection and m onitoring wells; perform post-injection monitoring; demonstrate the appropriateness of an alternative post-injection site care time frame; demonstrate non endangerment; and perform site closure activities. The guidance will be available at http://water.epa.gov/t ype/groundwater/uic/wells_sequestration.cfm.

EPA adds that the purpose of the GS rule is not to incentivize the use of GS; rather, the purpose of the GS rule is to ensure that, where GS is deployed, it is conducted in a manner that protects USDWs from endangerment.

Letter ID: 0191 Comment ID: 23881 Letter Lines: 164 to 169

Comment Code: 5220 2.8.2.1 Post-injection monitoring activities

Comment: performance and as such is more prot ective of USDWs. S econd, the proposal requires a showing that the CO2 plume has "stabilized", which is undefined. Cessation of plume movement is not necessari ly essential to show that a project poses no threat of endangerment to USDW s - plumes that are still moving may, nonetheless, remain contained. Instead, it is more protective to show that the

5plume is not expected to encounter a leakage pathway. Third, the required

Individual Response: EPA agrees that a complete cessation of plume movement may not occur at some sites for long time periods due to density differences, natural fo rmation flow gradients

and diffusion. EPA clarifies that under the final ru le, a complete cessation of plume movement is not required, only a demonstrati on that the plume and pressure front no longer pose a risk of endangerment to USDWs.

EPA acknowledges that many site-specific factors will influence the determ ination of when the CO2 plume and pressure front no lo nger pose a risk of endangerment to USDWs. It is for this reason that EPA believes that Directors, in c onsultation with operators, will be in the best position to determine whether additional post-inje ction site care is needed. EPA expects this

decision to be made based on relevant site data and in consultation with all potentially impacted parties. EPA also recognizes that there may be sites where the 50 year pos t injection site care timeframe may be either not appropriate or more burdensome than necessary based on sitespecific conditions. For this reason, the GS rule o ffers owners or operators flexibility regarding

the duration of the PISC timefra me by: (1) allowing the Direct or discretion to shorten or lengthen the PISC timeframe during the post-in jection period based on site-specific data, pursuant to requirements at §146.93(b) ; or (2) affording the Director discretion to allow a Class VI well owner or operator to demonstrate, during the permitting process based on substantial data, that an alternative PISC timeframe may be appropriate if it ensu res non-endangerment of USDWs pursuant to requirements at §146.93(c).

EPA is developing guidance to assist owners or operators in evaluating well plugging, postinjection site care, and site closure requirements of §146.92 and §146.93. Additionally, the guidance will assist Directors in evaluating propo sed well plugging plans a nd post-injection site care and site closure plans under §146.92 a nd §146.93. The guidance describes recommended approaches for how an owner or operator coul d plug injection and m onitoring wells; perform post-injection monitoring; demonstrate the appropriateness of an alternative post-injection site care time frame; demonstrate non endangerment; and perform site closure activities. The guidance will be available at h ttp://water.epa.gov/type /groundwater/uic/wells_sequestration.cfm.

Letter ID: 0191 Comment ID: 23882 Letter Lines: 169 to 172

Comment Code: 5220 2.8.2.1 Post-injection monitoring activities

Comment: plume is not expected to encounter a leakage pathway. Third, the required showing that "no additional monitoring is needed" does not provide guidance regarding how an operator is to show that no additional monitoring is needed. The proposal below provides specific guida nce on what the operator must show.

Individual Response: EPA acknowledges that many site-sp ecific factors will influence the determination of when the CO2 plume and pressu re front no longer pose a risk of endangerment

to USDWs. It is for this reason that EPA believe s that Directors, in c onsultation with operators, will be in the best position to determine whethe r additional post-injection site care is needed.

6EPA expects this decision to be made based on re levant site data and in consultation with all potentially impacted parties.

EPA agrees that a complete cessa tion of plume movement may not occur at some sites for long time periods due to density differences, natura l formation flow grad ients and diffusion. EPA

clarifies that under the fi nal rule, a complete cessation of plum e movement is not required, only a demonstration that the plume and pressure front no longer pose a risk of endangerment to

USDWs is.

EPA is developing guidance to assist owners or operators in evaluating well plugging, postinjection site care, and site closure requirements of §146.92 and §146.93. Additionally, the guidance will assist Directors in evaluating propo sed well plugging plans a nd post-injection site care and site closure plans under §146.92 a nd §146.93. The guidance describes recommended approaches for how an owner or operator coul d plug injection and m onitoring wells; perform post-injection monitoring; dem onstrate non endangerment; and perf orm site closure activities. The guidance will be available at http://water.epa.gov/type/groundwater /uic/wells_sequestration.cfm.

Letter ID: 0191 Comment ID: 23883 Letter Lines: 174 to 198

Comment Code: 1240 1.1.1.3 Suggested changes/ed its to rule language

Comment Code: 5200 2.8.2 Post injection site care (seeking comment) (40 CFR 146.93)

Comment: We recommend the standard in the propos ed alternative language for section 146.93(b) below because it sets forth detail ed criteria, all of which must be satisfied, to demonstrate that the site doe s not pose an endangerment to USDWs. The specific criteria listed in our propos al will serve to pr ovide the Director with the requisite information to make the appropriate determination. The advantage of this approach is that it establishes clear criteria that an operator must demonstrate before obtaini ng site closure based upon particular site characteristics and is, therefore, reasonably applicable to any storage site as opposed to a standard based up on a fixed-duration. Furthermore, it is more stringent than a purely discretiona ry approach because it establishes specific criteria that must be shown before site clos ure may be granted. We believe this language, which is an extens ion of work done by the World Resources

Institute and the Ground Water Protection C ouncil, avoids the noted shortcomings and provides stronger protection for USDWs.

146.93 (b) The owner or operator shall monitor the site following the cessation of injection.

(1) The owner or operator shall con tinue to conduct monitoring as specified in the Director-approved po st-injection site care and site closure plan until closure is auth orized pursuant to 146.93(b)(3).

7(2) The owner or operator can re quest and demonstrate to the

satisfaction of the Director that th e post-injection site care and site closure plan should be revised to reduce the frequency of monitoring.

Individual Response: EPA disagrees with the suggested edits, but believes that the provisions of the final GS rule at §146.93(b) address the comm enter’s suggestions. Spec ifically, the owner or operator must monitor the site until it can be demonstrated that the CO2 plume and pressure front no longer pose a risk of endangerment to USDW s and that monitoring must continue until the owner or operator demonstrates, based on mon itoring and other site-specific data, that no additional monitoring is needed to ensure th at the GS project does not pose a risk of endangerment to USDWs, as required at §146.93(b )(3). See the final rule and preamble for further discussion on EPA's final approach.

Letter ID: 0191 Comment ID: 23884 Letter Lines: 200 to 218

Comment Code: 1240 1.1.1.3 Suggested changes/ed its to rule language

Comment Code: 5280 2.8.2.4 USDW non-endangerment demonstrations

Comment: (3) Prior to authorization for site cl osure, the owner or operator must demonstrate to the Director, based on monitoring, othe r site-specific data, and modeling that is reasonably consistent with site performance, that no additional monitoring is needed to assure that the geologic sequestration project does not a nd is not expected to pose an endangerment to USDWs. The Director shall approve closure if the owner or operator demonstrates, based on th e current understa nding of the site, including monitoring data and/ or modeling, all of the following: (i) the estimated magnitude and extent of the project footprint (CO2 plume and the area of elevated pressu re) ; (ii) the estimated location of the detectable CO2 plume; (iii) th at there is no significant leakage of either CO2 or displaced formation fluids that is endangering USDWs; (iv) that the injected or displaced fluids are not expected to migrate in the future in a manner that encounters a potential leakage pathway into a USDW; (v) that the injection we lls at the site completed into or through the injection zone or confin ing zone are plugged and abandoned in accordance with these requirements; and (vi) any remaining project monitoring wells at the site are be ing managed by a person and in a manner acceptable to the Director.

Individual Response: EPA disagrees that the rule should specify the criteria for setting the monitoring timeframe. Instead, EPA believes that such determinations are site-specific and should be described in a project specific post-injection site care and site cl osure plan. EPA also believes that periodic reviews and updates, wh ere necessary, to the plan are important to ensuring that the site continues to be managed effectively and to determine whether shortening the monitoring timeframe is appropriate. The post-injection site care require ments in the final GS rule offer owners or operators flexibility regarding the duration of the PISC timeframe by: (1) allowing the Director discretion to shorten

8or lengthen the PISC timeframe during the pos t-injection period based on site-specific data, pursuant to requirements at §146.93(b) ; or (2) affording the Director discretion to allow a Class VI well owner or operator to demonstrate, during the permitting process based on substantial data, that an alternative PISC timeframe may be appropriate if it ensu res non-endangerment of USDWs pursuant to requirements at §146.93(c). EPA believes that a default post-injection site car e timeframe of 50 years, with flexibility to adjust the timeframe for a limited number of GS projects during the permitting process where

substantial data exists to demonstrate that an alternative timeframe would be protective of USDWs, or based on data collected during the PISC period, is appropriate to address the range of sites where GS is anticipated to occur, to ac commodate site-specific circumstances and various geologic conditions, and addre sses commenters’ concerns, wh ile ensuring USDW protection. Both approaches will utilize si te-specific data, and be based on pressure monitoring and USDW impacts.

EPA is developing guidance to assist owners or operators in evaluating well plugging, postinjection site care, and site closure requirements of §146.92 and §146.93. Additionally, the guidance will assist Directors in evaluating propo sed well plugging plans a nd post-injection site care and site closure plans under §146.92 a nd §146.93. The guidance describes recommended approaches for how an owner or operator coul d plug injection and m onitoring wells; perform post-injection monitoring; demonstrate the appropriateness of an alternative post-injection site care time frame; demonstrate non endangerment; and perform site closure activities. The guidance will be available at h ttp://water.epa.gov/type /groundwater/uic/wells_sequestration.cfm.

Letter ID: 0191 Comment ID: 23885 Letter Lines: 220 to 251

Comment Code: 5600 2.11 Comments related to UIC Program primacy for Class VI wells

Comment: Need for adequate implementation resources

Although not directly addre ssed in the EPA proposal, th e need for adequate resources to implement the regulatory progr am for geologic sequestration at both

the federal and state levels is a major consideration a nd one that EPA should be addressing both internally and in its di scussions with Congress. The annual national budget for the UIC program (approximately $11 million) has remained static for many years, while UIC agencies have been asked to take on additional responsibilities. Furthermore, inflation of salaries and other expenses has eroded the buying power of the unchangi ng UIC budget. If state and regional agencies are asked to take on the additio nal workload of CO2 injection, while ensuring careful scientific review as we ll as an expeditious processing time, they will require additional trai ned staff and other resources.

If the nation is serious about cont rolling CO2 through underground injection, significant additional resources will need to be made available to hire new permitting staff and field inspectors. Thos e new staff, along with the existing cadre of UIC staff and manage rs, must be trained in s ubjects that will enable

910 them to make prudent permitting, management, and oversight decisions. As momentum grows to begin sequestering CO 2 underground, EPA and states will need to develop new regulatory requirements fo r CO2 wells and prepare to review applications and make permitting decisions. Failure to provide sufficient resources will likely create permitting back logs, resulting in a bottleneck in the overall geologic sequ estration effort.

The Ground Water Protection Council (GWPC) estimated in 2004 that an annual funding increase to $56 million would be need ed just to meet the needs of the existing UIC program at the state level even without the addition of geologic sequestration project permitting.[FN2/] GWPC has further estimated that EPA will need to provide funding at a level of $100 million annually to meet the needs for the full UIC program, including the regulation of geologic sequestration. [FN2/: GWPC, Class V Resource Needs Survey, Summary (September 2004).]

Individual Response: EPA acknowledges that there may be technical and administrative challenges including resource concerns , and will work closely with the states to assist them in resolving funding issues or acquiri ng the resources, personnel, and training needed to address the unique technical challenges associated with GS.

EPA will also incorporate Class VI wells into the UIC Program's grant allocation process. The

States/Tribes/Territories must also demonstrate th at they have adequate resources to implement the program through matching resources against those allocated by the UIC Program's grant allocation formula. Currently, primacy programs ar e required to meet a minimum of 25 percent matching requirement.