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.Letter ID: 0134

Commenter: Dawn A. Thorne Organization: University of Utah Energy and Geoscience Institute on behalf of the Southwest Regional Partnership

Letter ID: 0134 Comment ID: 21652 Letter Lines: 26 to 37

Comment Code: 1420 1.2.1.1 Support the GS rulemaking

Comment: The Southwest Regional Partnership (SWP ) is one of seven (7) regional partnerships selected by the United Stat es Department of Energy (DOE) and National Energy Technology Laboratory (NETL) to characterize, evaluate, test, and verify the feasibility of carbon dioxide sequestration within our particular region. As such, the SWP is curren tly conducting three (3) geologic sequestration (GS) pilot studies and one (1) terrestrial seque stration project, with a fourth GS pilot study to begin in the middle of 2009. The SWP would like

to commend the Environmental Protecti on Agency (EPA) for recognizing the importance of carbon capture and storage (CCS ) and making an effo rt to create a sound regulatory process that is protective of human health and the environment.

On behalf of the SWP, we would like to submit the following comments on the proposed rule to public record:

Individual Response: EPA believes that the creation of a new injection well class (VI) under the existing UIC Program is necessary to enable the use of GS as a climate change mitigation technology in a manner that protects USDWs from endangerment. EPA agrees that the UIC Program, under the authority of the SDWA, provides a strong fram ework for regulating injection of CO2 for GS and adds that the GS regulati on tailors the UIC requirements to address the unique issues associated with large-scale GS including large injection volumes, the relative buoyancy of CO2, its corrosivity in the presence of water, the potenti al presence of impurities in captured CO2, and its mobility within subsurface geologic formations.

Letter ID: 0134 Comment ID: 21653 Letter Lines: 39 to 46

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

Comment Code: 1600 1.3 Risk Associated with CO2 GS

Comment: 1.) The SWP would like to recommend a risk-based approach to the siting requirements, Area of Review (AoR), m onitoring requirements, site-closure requirements, and the grandfather clause. The EPA notes in several places within the proposed rule that each GS site is unique with respect to physical and chemical properties. As such, the SW P recommends that the EPA adopt a risk/performance-based approach for each site. Reasoning for this recommendation as it relates to specific aspects of the proposed rule are outlined by relevant

sections:

1Individual Response: EPA has taken a regulatory approach that promotes USDW protection, incorporates flexibility or permitting authority di scretion when appropriate, seeks to limit burden on owners or operators and permitting agen cies, and provides a foundation for national consistency in permitting of GS projects. Under the final rule, many of the permit requirements must be established through site -specific plans (e.g., AoR and corre ctive action plan, testing and monitoring plan, etc.) developed by the owne r or operator and appr oved by the Director. Consequently EPA expects that owners or opera tors will consult with the Director as they develop, implement, and update these plans. Ad ditionally, the Director has the discretion to approve alternatives to the requirements in some cases. For example, the Director may in certain situations modify the length of the post-injecti on site care period or appr ove an alternative postinjection site care timeframe as part of th e permitting process under §146.93, allow the use of alternate methods for mechanical integrity testing (if approved by EPA) under §146.89, and waive the requirement that wells be designed to inject below the lowermost USDW under

§146.95.

Letter ID: 0134 Comment ID: 21654 Letter Lines: 48 to 71

Comment Code: 3120 2.1.2 Need to identify additional confining and containment zones (seeking comment)

Comment: - Section 146.83(b) "At the Director's disc retion, owners or op erators of Class VI wells must identify and characterize additional zones that will impede

vertical fluid movement, ar e free of faults and fractur es that may interfere with containment, allow for pressure dissipation, and pr ovide additional opportunities for monitoring mitig ation and remediation."

Response/Discussion: These zones would im ply that "secondary containment" is necessary for GS. Such zones are not re quired for Class I ha zardous waste wells, thereby giving the impression that GS is more risky than the underground storage of hazardous waste. While a "stacked syst em" of reservoirs and seals certainly provides additional safeguards to undergr ound sources of drinking water (USDWs), in general, these containment zones will not be necessary in every case, especially when it can be demonstrated th at seal integrity will be maintained over the life of a GS project. As stated in the proposed rule, "...their absence does not necessarily indicate inappr opriateness of a GS site".

The SWP agrees with the testimony of Ed ison Electric Institute at the Public Hearing on September 30, 2008 (Chicago, IL), th at such an additional requirement would create the perception of fear am ong the public. Through international and national GS pilot studies of various scales, it has been demonstrated that it is very unlikely that GS would harm human health and the environment when sited properly. The SWP would recommend that the EPA remove this section from the final rule, since detailed siting evaluation is explicitly covered in Sections 146.83(a)(1,2).

Individual Response: EPA retains the requirement to iden tify additional containment/confining

2zones, if required by the Di rector, as proposed (§146.83(b)). EPA acknowledges that such additional zones may not be needed in all circumst ances, and clarifies that this requirement is at

the Director's discretion, based on his or her understanding of a part icular site. EPA believes that, in some situations, the presence of additional confining and containment zones above the primary (i.e., lowermost) confining zone can improve USDW protecti on. These layers could further impede vertical fluid movement and al low for pressure dissipation, and also provide additional sites for monitoring, mitigation, and re mediation. The Agency's decision is supported by commenters representing states, water associati ons, and an electric utility who assert that these requirements promote a flexible, risk-base d, site-specific approach to characterizing and permitting a site for GS projects, and are intende d to improve understanding of the project as a whole and promote better modeling of the site.

Letter ID: 0134 Comment ID: 21655 Letter Lines: 73 to 87

Comment Code: 3530 2.2.3.1 AoR reevaluation fre quency (seeking comment)

Comment Code: 3560 2.2.3.2 Conditions that merit reevalua tion of the AoR (seeking comment)

Comment: - Section 146.84(b)(2)(i) "A description of The mini mum fixed frequency, not to exceed 10 years, the owner or operato r proposes to reevaluate the area of

review; "

Section 146.84(b)(2)(ii) "The monitoring and operational conditions that would

warrant a reevaluation of the area of review prior to the next scheduled reevaluation as determined by the mini mum fixed frequency established in paragraph (b)(2)(i) of this section "

Response/Discussion: The SWP recommends adopting a risk/performance-based approach to AoR re¬evaluation. Since each s ite is unique, it may be best for the operator to work directly with the EPA Director to establish an evaluation

schedule that would occur as often as need ed, but not more than needed. The SWP agrees that re-evaluations should be based on updati ng, revising, and calibrating computational models with site-specific data.

Individual Response: EPA agrees that site-specific fact ors should be considered in the

reevaluation schedule, and notes that the AoR and corrective acti on plan must specify the sitespecific monitoring and operationa l conditions that warrant r eevaluation, as specified in §146.84(b)(2)(ii). In addition, the Director has discretion to require more frequent AoR

reevaluation if he or she has r eason to believe, based on site-speci fic information, that a five-year

reevaluation schedule is not sufficiently pr otective of USDWs.

However, EPA believes that period ic AoR reevaluation at a set fre quency is necessary to ensure protection of USDWs from endangerment and addr ess the uncertainties inherent in predictive modeling. Periodic AoR reevaluati ons at §146.84(e) ensure that a deliberate effort is made to verify, based on monitoring and operational data, that the CO2 plume is moving within the subsurface as predicted. EPA belie ves that less frequent reevaluati ons may not be sufficient to appropriately model plume and pressure front movement, establish conditions for corrective

3action, and ensure protection of USDWs from endangerment.

EPA clarifies that if site m onitoring data agrees with the existing AoR delin eation, a model recalibration may not be necessary, and the AoR reevaluation may consist of a demonstration

that the current AoR delineation is ad equate based on site monitoring data.

Letter ID: 0134 Comment ID: 21656 Letter Lines: 89 to 111

Comment Code: 3630 2.2.4.1 Comments in favor of allowing phased corrective action

Comment: - Section 146.84(3)(d) "Owner s or operators of Class VI wells must perform

corrective action on all wells in the area of review that are determined to need corrective action using methods necessary to prevent the movement of fluid into or between USDWs including use of co rrosion resistant materials, where appropriate."

Response/Discussion: The SWP strongly suppor ts a phased approach to corrective

actions as indicated in the Federal Register, page 43508. This discussion includes the following benefits to pha sed corrective actions: "There are potential benefits to implementing pha sed corrective action. Phasing in the

corrective action would bene fit the owner or operato r by spreading out the

burden and costs of corrective action a nd not delaying initiation of the GS project while corrective acti on is performed at wells th at may not be affected by the injection for several decades. Initial corrective action would focus on those penetrations that pose a potential endangerment to USDWs from injection of CO2 in the near term. Deferring correctiv e action on some of the wells at the outer reaches of the predicted plume can improve USDW protection by giving these

later corrective action efforts the benefit of newer corrective action techniques. Additiona lly, this approach can preven t the unnecessary burden of performing corrective action in areas far fr om the injection zone that may never be impacted This approach would still assu re that all wells in the AoR that need corrective action eventually receive it, as is the case in current UIC requirements."

Individual Response: EPA acknowledges the commenter’s s upport of phased corrective action and agrees that phased corrective action may provide many benefits to a project including, but not limited to, spreading the burden of cost, avoi ding delays in project start-up, allowing for use of future, improved corrective act ion techniques and addressing unanticipated changes in the movement of the CO2 plume or pressure front . EPA believes that the phased corrective action approach is appropriate for GS projects, and retained it at §146.84(b)(2)(iv) in the final GS regulation.

Letter ID: 0134 Comment ID: 21657 Letter Lines: 113 to 127

4Comment Code: 4324 2.4.4.1.2 Comments opposed to requiring injection below the lowermost

USDW

Comment: - Section 146.86(b)(2) "Surface casing mu st extend through the base of the

lowermost USDW and be cemented to the surface."

Response/Discussion: It is the opinion of the SWP that this section may unnecessarily eliminate viable target rese rvoirs from GS. The SWP recommends a site-specific risk-based approach for de termining siting criteri a. As discussed in the first point of this letter, deta iled siting criteria with respect to injection and confining zone s are evaluated in Section 146.83(b) of the proposed rule. A definitive rule eliminating injecti on into any zone above a USDW without scientific justification appears to be preliminary in nature and again, may create the perception of fear among th e public. The SWP recommends either removing this section from the final rule or , if kept in the ru le, then it be expanded to include a site -specific, risk-based approach for approval of drilling, casing, and other relevant varian ces into an injection zone above a

USDW.

Individual Response: EPA acknowledges that there are lim ited circumstances where injection above the lowermost USDW can be performe d in a manner that protects USDWs from endangerment, as long as appropriate protections are in place. The final GS rule at §146.95 establishes a process by which owne rs or operators can seek a waiv er of the Class VI injection depth requirements for injecti on into non-USDW formations above and/or between USDWs. The waiver approach requires the submission of exte nsive, site-specific information (in conjunction with the permit application submission) to dem onstrate that injection of CO2 into a non-USDW

that is above or between USDW s can be done in a manner that is protective of USDWs. The requirements are designed to ensu re that the owner or operator, the Director, and the Regional

Administrator consider, on a site specific basis, the implications, benefits, and challenges associated with GS and ensuring water availability and USDW protection. EPA believes that the additional procedures for public notice of a wa iver application and for Director-Regional Administrator communication at §146.95 will improve public confidence in and acceptance of GS projects operating under in jection depth waivers. EPA clarifies that, due to the unique nature of the injection depth wa iver process and in an effort to ensure national consistency and application of the requirements, the requirement at §146.95(d) indicates that the Regional Administrator ma kes the final determination regarding waiver issuance following an evaluation of all site -specific information, public notice, and

recommendations from the UIC Director. EPA agrees that a site-specific approach is ap propriate. The waiver approach requires the submission of extensive, site-specific informa tion (in conjunction with the permit application submission) to demonstrate that injection of CO2 into a non-USDW that is above or between USDWs can be done in a manner that is protectiv e of USDWs. For additional information on the waiver approach, please see the final rule and preamble, as well as EPA's responses to comments on the Notice of Data Availability and Request for Comment.

5Letter ID: 0134 Comment ID: 21658 Letter Lines: 129 to 143

Comment Code: 4110 2.4.1.1 Injection pressure limitations

Comment: - Section 146.88(a) "Except during stimulation, the owner or operator must ensure that injection pressure does no t exceed 90 percent of the fracture pressure of the injection zone so as to assure that the injection does not

initiate new fractures or propagate existing fractures in the injection zone(s) or cause the movement of injection or fo rmation fluids that endangers a USDW." Response/Discussion: It should be noted that for GS, injection pressure must be maximized. As the pressure spreads, the state of stress away from the well will also change. It must also be considered that unmapped faults could exist at some distance away from the injection well. Th e pressure needed to reactivate or propagate these faults could be less than 90 percent of the fracture pressure. The SWP would like to recommend a site-spe cific, performance-based approach to injection pressure requirements. Con tinuous site monitoring (discussed in Sections 146.88(e) and 146.90(g)) along with a detailed mitigation plan, will help operators and the EPA Director devel op site-specific injection pressure and mitigation plan requirements.

Individual Response: EPA agrees that the maximum injecti on pressure should be based on sitespecific conditions. During the site characterizati on process, owners or operators must submit data about the geology of the site, as speci fied at §146.82(a), includ ing data on known or suspected faults and fractures and geomechanical information on fractures, stress, ductility, rock strength, and in situ fluid pressu res within the confining zone. If the Director determines, based

on a review of this information, that a lower in jection pressure limitation is appropriate, the Director has the authority to set a lower limit in the operating permit. EPA adds that any sites with the potential for reopening or reactivation of faults or unaccep table seismic risk that could

otherwise interfere with containment will not be permitted as GS sites.

Letter ID: 0134 Comment ID: 21659 Letter Lines: 145 to 156

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

Comment Code: 5260 2.8.2.3 Adjusting the post-injecti on timeframe (seeking comment)

Comment: - Section 146.93(b)(1) "The owner or operator shall con tinue to conduct monitoring as specified in the Director-approved post- injection site care and site closure plan for at least 50 years following the ce ssation of injection. At

the Director's discretion, the monitori ng will continue until the geologic sequestration project no longer poses an endangerment to USDWs."

Response/Discussion: The SWP recommends adop ting a performance-based approach to the site care period so that each site is monitored for as long as necessary, but not longer than necessary in order to avoid an extra cost burden to regulators and owners/operato rs. The required site-specifi c "post-injection site care and site closure plan" appears suffi cient to convey appropriate monitoring

6techniques and timescales to the EPA Director.

Individual Response: EPA agrees that there will be circumst ances where it can be demonstrated in less than 50 years that the plume and pressure front no longer pose a risk of endangerment to

USDWs. For this reason, the GS ru le offers owners or operators flexibility regard ing the duration of the PISC timeframe by: (1) allowing the Direct or discretion to shorten or lengthen the PISC timeframe during the post-injecti on period based on site-specific da ta, 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 acknowledges the commenter’s support of the pos t-injection site care a nd site closure plan; the final GS regulation retains this provision.

Letter ID: 0134 Comment ID: 21660 Letter Lines: 158 to 172

Comment Code: 2060 1.5.3 Comments on grandfathering of existing wells (seeking comment)

Comment: - Section 146.81(c) "This subpart applies to owne rs and operators of permit or rule-authorized Class I industri al, Class II, or Cla ss V experimental carbon dioxide injection projec ts who seek to apply fo r a Class VI geologic sequestration permit for their well or wells. If the Director determines that USDWs will not be endangered, such wells are exempt, at the Director's discretion, from the casing and cementi ng requirements at .¢§ 146.86(b) and 146.87(a)(I) through (3)."

Response/Discussion: Only the casing and cementing requirements would be "grandfathered" into the Class VI perm it if accepted by the EPA Director. The SWP recommends the consideration of gra ndfathering Class I, II, and V permits into the Class VI category on a site-specific basis. Many of the Class VI regulations mirror Class I, II, and V pe rmit regulations, therefore, the time and budget it would require the owner/operato r and EPA Director to re-permit an existing well may not be required.

Individual Response: EPA agrees that many Class I, Cl ass II, and Class V experimental technology wells are designed and constructed to withstand exposure to CO2. The final GS rule

7provides that the construction of these wells be grandfathered per §146.81(c), provided the owner or operator can demonstrate to the Director that the wells were en gineered and constructed to meet the requirements at §146.86(a) and ensure protection of USDWs, in lieu of requirements at §146.86(b) and §146.87(a).

EPA disagrees with commenters who suggest th at other requirements (outside of well construction) should also be grandfathered. Foll owing re-permitting of the project as GS, many of the unique factors of GS s ites (e.g., increased reservoir pr essures associated with large volumes of stored CO2 and the corrosivity of CO 2 in the presence of water) will result in an increased risk profile, warranti ng the specific requirements in the final GS rule. Therefore, following re-permitting as Class VI wells, these proj ects must be subject to the operational, MIT, monitoring, reporting, plugging, and post- injection site care and site closure requirements in the

final GS rule. See the discussion of EPA's final regulatory approach in the preamble to the GS rule for additional detail on these requirements.

Letter ID: 0134 Comment ID: 21661 Letter Lines: 174 to 201

Comment Code: 5430 2.9.1 Comments on proposed financia l responsibility requirements (40 CFR 146.85)

Comment: 2.) The SWP would like to comment on site liability.

Section 146.85(a) "The owner or operator mu st demonstrate and maintain financial responsibility and resources for correctiv e action (that meets the requirements of §146.84), injection well plugging (that meets the requirements of §146.92), post-injection site care and site closure (that meets the requirements of §14693), and emergency and remedial respons e (that meets the requirements of §I46.94) in a manner prescribed by the Director until ...."

Response/Discussion: While l ong-term liability with resp ect to property rights, personal risk, air quali ty, etc. are beyond the scope of the proposed rule, the

SWP would like to note that it would be highly unlikely for any commercial scale GS project to be initiated without pr ivate insurance or a state/federal revolving assurance fund that could cove r the project from the beginning to beyond site-closure ("cradle to grave"), which, with a 50-year post-injection site care plan, could be over one hundr ed years. Since long-term CCS is relatively new and the potential "risks" are not well understood by insurers, it is unlikely that any private insurer would cover a projec t for such a time span, but rather they may create a renewable policy over short timescales (i.e., 2-5 year increments). In add ition, there is no assurance that an owner/operator would still be in business 50 years (a nd beyond) after CO2 injection ceases.

The SWP agrees with financial responsibi lity requirements under the current UIC Program for Class II wells as they relate to the injection period and recommend that these be adopted for Class VI wells. The issues of liabil ity and financial responsibility for post-injection site care and after site clos ure will severely

8impact private/public industry's decisi on to conduct CCS pr ojects if these requirements are too burdensome to fulfill.

Individual Response: The goal of financial responsibility is to assure that resources are available to prevent endangerment of US DWs from improper plugging, remediation, and management of wells in the event that the owne r or operator experiences financial difficulties. EPA agrees that assuring financial responsibil ity for corrective action on wells in the AoR, injection well plugging, PISC and si te closure, and emergency and remedial response at GS sites is an important component of ensuring that US DWs are protected. EPA has specified acceptable financial responsibility instruments in the final regulation, believes that the tailored financial responsibility requirements at §146.85 ar e appropriate for Class VI wells.

EPA anticipates that the availability of thir d-party GS financial instruments will grow in response to demand for such instruments by Class VI well owners or operators as deployment of GS technology increases in the future. In addition, EPA plans to allow owners or operators to choose from a variety of financial instruments to meet their financia l responsibility needs, thereby allowing owners or operators to select instruments they find eas iest to obtain. See the final rule and preamble for further discussion of EPA's final approach to financial responsibility.

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.

9§§ 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: 0134 Comment ID: 21662 Letter Lines: 203 to 218

Comment Code: 5460 2.9.2 Comments on transfer of lia bility for long-term care

Comment: The SWP supports the recommendation of the IOGCC [Footnote IOGCC. 2007. A Legal and Regulatory Guide for States and Provin ces. Task Force on Carbon Capture and Storage, IOGCC, September 25, 2007.] to create a state-administered compensation fund for post site closure stewardship for the following reasons:

- The SWP agrees that states/provinces are in the best position to oversee CCS regulatory compliance with in their jurisdiction; - The funding mechanism is sound and has a history of success with abandoned or orphaned oil and gas wells and underground storage tank release

sites; - The SWP agrees that afte r a site has been successfully closed, liability should transfer from the owner/operator to the state(s), who can assure that the site is properly monitored and maintained; and - Long-term post-closure liability left in the hands of the owner/operator would hinder many (if not all) comme rcial scale CCS projects from implementation.

Individual Response: Under the final GS rule, once an owne r or operator has met all regulatory requirements under Part 146 for Class VI wells and the Director has approved site closure pursuant to requirements at §146.93, the owner or opera tor will generally no longer be subject to enforcement for regulatory noncompliance. Furtherm ore, their financial instrument as required under §146.85 will be released if it was not used. However, even if a site closure is approved under §146.93, an owner or operator may be held liable for regulatory noncompliance (including violation of 40 CFR 144.12) in ce rtain circumstances. For example, an owner or operator may be held liable for regulatory noncompliance even afte r site closure was approved if the Director relied on erroneous information (e.g., erroneous modeling data) provid ed by the owner or operator when approving site closure.

Separate from EPA’s authority to enforce regul atory compliance, an owner or operator may be subject to a §1431 response orde r even after proper site cl osure is approved under §146.93. Under §1431 the Administrator may require an ow ner or operator to take necessary response

measures if he or she receives information that a contaminant is present or is likely to enter a public water system or an USDW, which may pres ent an imminent and s ubstantial endangerment to the health of persons, and the appropriate Stat e and local authorities ha ve not acted to protect the health of such persons. Th e action may include issuing admi nistrative orders or commencing a civil action for appropriate relief against the ow ner or operator of a Class VI well. If the owner

10or operator fails to comply with the order, they may be subject to a civil penalty for each day in

which such violation occurs or failure to comply continues.

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. Please note that EPA does not have authority to transfer SDWA or other legal liability for Class VI wells to the State or federal gove rnment or a third-party fund. See the final rule preamble for further discussion of EPA's final approach.

Letter ID: 0134 Comment ID: 21663 Letter Lines: 220 to 234

Comment Code: 1300 1.1.2.3 Comments on other aspects of CCS (capture, transport)

Comment: 3.) The SWP would like to comment on the compatibility of the proposed rule with other regulatory processes.

The CCS process is extremely complex. The proposed rule is associated with storage of CO2 as it relates to protec ting USDWs under the UIC program. Other aspects of the process incl uding capture, compression, and transport of CO2 are not addressed within the pr oposed rule, and rightfully so since those processes are independent of the UIC program. In the overall scheme of permitting a commercial scale CCS site, has any consider ation been given to the compatibility of the UIC proposed rule with other pe rmitting processes (i.e., pipeline, air quality, etc) so as to streamline all regulatory requirements? The SWP would like to suggest collaboration with othe r permitting agencies, at the state and federal level, as regulatory framework development progresses so that the permitting of an entire CCS project is not unrealistically burdensome for the regulators and owne rs/operators.

Individual Response: EPA agrees that a strong regulatory framework will be important to ensuring that GS is deployed safe ly. EPA believes that the Class VI GS regulation will provide certainty, consistency, and transparency to owners or operators and the public about requirements that apply to GS injection across the United States . The Class VI GS regulation builds upon the long-standing, protective framew ork of the UIC program, which has been regulating the injection of billions of gallons of liquids for decades. The Class VI GS regulation enhances this existing framework with requirements for GS wells that are tailored to the unique nature of large scale GS of CO2. These additional protectiv e requirements include more extensive geologic test ing, detailed computational modeli ng of the AoR and periodic reevaluations, detailed requirements for monitori ng and tracking the CO2 plume and pressure front, and extended post-injecti on monitoring and site care.

In response to the suggestion that the Agency develop an integrated permitting process that addresses the entire CCS process, EPA clarifie s that the UIC program’s authority under SDWA is focused on ensuring protection of USDWs fromendangerment. The capture and transport of CO2 are outside of the scope of the Class VI GS rulemaking.

11Letter ID: 0134 Comment ID: 21664 Letter Lines: 236 to 249

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: 4.) The SWP would like to comment on ar ea permits and dual-purpose wells as they relate to commercial scale sequestration fields.

The purpose of the proposed Class VI well is strictly for injection of CO2. The SWP would like to point out that for a comm ercial scale sequestration site there may be several injection wells that serve multiple purposes (i.e., injection of CO2, injection of brine, production of CO2 and production of brine). For example, one of the mitigation strategies for relieving pressure on an injection reservoir may be to produce either injected CO2 or displaced brine. As a form of "waste management", it may be desirable to re-inject the prod uced brine into another reservoir. In that case, a singl e well could serve as a CO2 injection well, brine disposal well, and production well. The SWP recommends that the EPA address the permitting requirements for both a large area (i.e., area permit) and dual-purpose wells in relati on to geologic sequestration.

Individual Response: EPA disagrees that area permits are a ppropriate for GS projects or that dual-purpose wells may be permitted as Class VI wells. EPA clarifies that the Class VI requirements in the GS rule are for CO2 inject ion for long-term storage of large volumes of CO2. EPA acknowledges that multiple wells may inte ract at a given GS site. EPA also believes that requiring separate permit applications for eac h GS well will ensure sufficient review and that the public has an opportunity to provide input on each well in the field as it is constructed or brought online.

EPA is developing guidance on transitioning perm its from Class II to Class VI. The guidance will assist Directors in evaluating whether an injection project should transition from Class II where the primary purpose is oil and gas producti on to Class VI where the primary purpose is long-term storage of large volumes of CO2. Th e guidance describes the methods available for the Director to determine changes in risk to USDWs from projects, and how the Director may determine whether a project should be regulated within the Class II or Class VI UIC program. This guidance will be available on EPA’s website at http://water.epa.gov/type/groundwat er/uic/wells_sequest ration.cfm. For more information, please

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

Letter ID: 0134 Comment ID: 21665 Letter Lines: 251 to 257

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

Comment: In conclusion, the SWP recommends a si te-specific, performance/risk-based approach to the fmal regulatory fr amework. This method will allow for consideration of the uniqueness of each CCS site, and accommodate advancements

1213 in technology over time. The SWP would also urge collaboration with other regulatory agencies and pr ivate insurers to esta blish a sound regulatory framework with long-term f unding and oversight at the st ate level. Thank you for the opportunity to comment.

Individual Response: The Agency believes that the Class VI requirements balance site-specific flexibility with USDW protection. Rather than setting performance or technology-based standards for GS projects, EPA is adopting a flex ible approach, where operators of GS projects would develop and implement site-specific plans for delineating the AoR, testing and monitoring the site, performing corrective actio n, and post-injection site care . EPA believes that the plans— which would be reviewed and approved by the Director and periodical ly updated throughout the life of the project—promote an ongoing dialogue between the operato r and the Director that will encourage use of the most appropriate t echnologies for a particular project.