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.

### BEFORE THE UNITED STATES

ENVIRONMENTAL PROTECTION AGENCY

____________________________________________ ) Notice of Proposed Rulemaking ) Federal Requirements Under the ) Underground Injection Control (UIC) Program ) EPA-HQ-OW-2008-0390 for Carbon Dioxide (CO 2 ) ) FRL-8695-3 Geologic Sequestration (GS) Wells ) ) ) 73 Fed. Reg. 43492 (July 25, 2008) ) ___________________________________________)



### Comments of:

Clean Air Task Force –

– Clean Water Action –

– Environmental Defense Fund –

– Natural Resources Defense Council –

– Western Resource Advocates

A. Introduction

The Clean Air Task Force, Clean Water Action, Environmental Defense Fund, Natural Resources Defense Council, and Western Resource Advocates (Environmental NGO Group) thank EPA for the opportunity to comment on the Proposed Rule on carbon dioxide sequestration wells under the Underground Injection Control (UIC) Program.

Founded in 1996, the Clean Air Task Force (CATF) is a nonprofit organization dedicated to restoring clean air and healthy environments through scientific research, public education, and legal advocacy

.

Founded in 1972, Clean Water Action (CWA) has 1.2 million members and offices in 20 states. Clean Water Action works to improve public health and environmental protection through grassroots organizing, policy research and advocacy

.

Environmental Defense Fund (EDF), founded in 1967, is a non-profit organization that represents more than 500,000 members. EDF links science, economics and law to create innovative, equitable and cost-effective solutions to society’s most urgent environmental problems.2 The Natural Resources Defense Council (NRDC) is a national, nonprofit organization of scientists, lawyers and environmental specialists dedicated to protecting public health and the environment. Founded in 1970, NRDC has more than 1.2 million members and online activists nationwide, served from offices in New York, Washington D.C., San Francisco, Los Angeles, Chicago and Beijing.

Western Resource Advocates (WRA) is a regional non-profit organization using law, economics and policy analysis to protect the land, air and water of the Interior Western United States.

The planet’s climate is changing fast. Greenhouse gas emissions from the use of fossil fuels, mainly carbon dioxide (CO 2 ), are having a profound effect on our climate, presenting us with one of the most significant environmental and social challenges of the century. In its most recent Assessment Report last year, the Intergovernmental Panel on Climate Change, an independent scientific body, issued the loudest warning to date, calling the warming in the climate system “unequivocal” and calling for serious emission reductions if we are to avoid truly dangerous greenhouse gas concentrations. Failure to pursue significant reductions in greenhouse gas emissions very soon will make it much harder in the future both to stabilize atmospheric pollution concentrations and to avoid the worst impacts of climate change. Climate change is expected to and, indeed, already is having a profound effect on sources of drinking water. The American West, for example, is already becoming noticeable hotter and drier, as a recent compilation of studies by the Rocky Mountain Climate Organization (RMCO) and NRDC

summarizes. 1

A growing body of scientific research indicates that we face extreme dangers to human health, economic well-being, and the ecosystems on which we depend if global average temperatures are allowed to increase by more than 2 degrees Fahrenheit from today’s levels. We have good prospects of staying below this temperature increase if atmospheric concentrations of CO 2 and other global warming gases are kept from exceeding 350 to 450 parts per million (ppm) CO 2 - equivalent. Achieving this goal will require rapid reductions in existing emissions, including action to cut emissions by approximately 80% by mid-century. This goal is ambitious, but achievable. It can be done through an annual rate of emissions reductions that ramps up to about a 4% reduction per year. Fortunately, a wide variety of tools is available today to achieve those

reductions.

While it is not a “silver bullet”, one important tool is the geologic sequestration (GS) of CO 2 at properly selected and properly regulated sites. Our Environmental NGO Group does not necessarily have a common view concerning the magnitude of the long-term role of GS in combating climate change, but we are united in recognizing that a transition away from fossil fuels will take time and that GS is likely to be an important part of the near- to medium-term solution. Fortunately, capturing CO 2 and permanently sequestering it in certain types of wellselected and well-managed geologic formations is a technology that is ready to begin deployment today. While GS projects can be permitted today under the Safe Drinking Water Act’s (SDWA) UIC program (in fact a number of projects have already been permitted under existing well classes), the rules that currently apply to such projects were not designed with

1 “Hotter and Drier: The West’s Changes Climate”. Rocky Mountain Climate Organization (RMCO) and the Natural

Resources Defense Council. Available at: http://www.nrdc.org/globalWarming/west/west.pdf3 geologic sequestration in mind. Thus, the importance of this rulemaking is not that it is needed in order for GS projects to receive permits; rather, the rulemaking is important because it can assure that GS projects are regulated under rules that are specifically designed to require GS projects to be done safely and effectively without endangering underground sources of drinking water (USDWs) or, as discussed below, resulting in a risk of release to the atmosphere. For that reason, it is essential that EPA promulgate final rules for GS in a timely manner that are sufficient to protect USDWs.

It is also essential that the U.S. Environmental Protection Agency (EPA) take supplemental action, based on other (non-SDWA) authority, to provide additional assurance that injected CO 2 will not be released into the atmosphere in a way that adversely impacts the climate or otherwise endangers public health and welfare. Generally, the steps needed to protect USDWs are also needed in order to prevent emissions to the atmosphere. Supplemental steps citing additional authority should also guarantee that CO 2 injected into geologic formations stays out of the atmosphere. This should be done according to a permanence (performance) standard, which will certify CO 2 as ‘geologically sequestered’ for that purpose, in addition to protecting USDWs. These are needed, as none of the existing or proposed injection classes are adequate for the task of certifying CO 2 as permanently sequestered for the purposes of preventing atmospheric releases. In order to be fully protective of the environment, Congress will also need to pass comprehensive cap and trade legislation to control the emission of greenhouse gases from all anthropogenic sources. But the need for such legislation is not a basis for deferring the adoption of EPA rules to protect USDWs or to assure that injected CO 2 does not result in harmful releases to the atmosphere.

The Supreme Court recognized in Massachusetts v. EPA 2 that EPA has authority and, indeed an obligation, under the Clean Air Act to regulate emissions of greenhouse gases, including CO 2 , that “cause or contribute to air pollution that may reasonably be anticipated to endanger public

health or welfare.” 3 Similarly, the D.C. Circuit’s remand of the power plant new source performance standards (“NSPS”) places EPA in the position to regulate CO 2 emissions from new and also existing sources within that industrial sector. 4 The Environmental Appeals Board EAB also recently has rejected the agency’s arguments that it is not authorized to issue best available control technology (BACT) emissions limits for CO 2 in the context of a new source air permit decision for a large new coal-fired power plant, under the Clean Air Act’s Prevention of Significant Deterioration (PSD) new source review authority. 5

In comments on the Agency’s recent advanced notice of proposed rulemaking on using the Clean Air Act to combat climate change, a coalition of environmental NGOs, including some members

2 127 S.Ct. 1438 (2007).

3 Id . at 1460-61.

4 Order, NY, et al. v. EPA , D.C. Cir. No. 06-1322 (Sept. 24, 2007). On ce NSPS are set for an industry under section 111(b), 42 U.S.C. §7411(b), the Act requires EPA to set standards for states to regulate emissions from existing sources in that industry. 42 U.S.C. § 7411(d).

5 In re: Deseret Power Electric Coop., PSD App. No 07-03, Slip Op. (Nov. 13, 2008). The memorandum issued December 18, 2008 by Administrator Johnson entitled “EPA’ Interpretation of Regulations that determine Pollutants Covered by Federal Prevention of Significant Deterioration (PSD) Permit Program” (Johnson PSD memo) is procedurally deficient, and, in any event, states explicitly on its face that it is not intended to supersede the EAB’s

decision in the Deseret case. Johnson memo at 2. Nor, indeed, can it lawfully do so.4 of our Environmental NGO Group, pointed out that for the U.S. to achieve its necessary climate goals, controlling CO 2 emissions from new and existing sources of CO 2 is required. That necessitates reductions from all sectors, including radical shifts to zero-emitting technologies and corrective action on existing sources. These reductions will require targeted measures and policies, which include air regulations that would set CO 2 emissions standards implicating the capture and sequestration of CO 2 . Setting an NSPS or a BACT standard based on CO 2 capture technology necessarily creates a need for complementary requirements to assure that the captured CO 2 is effectively isolated from the atmosphere. At this time, such an outcome requires injecting CO 2 underground for permanent sequestration in either hydrocarbon reservoirs or deep saline formations. Such permanent sequestration clearly meets the definition of underground injection, regulated by the UIC program of the Safe Drinking Water Act (“SDWA”). 6

We therefore are pleased to submit these comments on EPA’s proposed rules concerning

“ Federal Requirements Under the Underground Injection Control (UIC) Program for Carbon Dioxide (CO 2 ) Geologic Sequestration (GS) Wells, 73 Fed. Reg.43492 (July 28, 2008).



### B. The Safe Drinking Water Act Authorizes EPA to Create a Preventive, Forward Looking, and Adaptive Program Specific to CO 2 

### GS Permitting

Under the SDWA, EPA’s authority to protect USDWs is clearly defined, broadly scoped, and forward looking. 7 Section 1421 requires the Administrator to publish rules for state implemented underground injection programs that “prevent underground injection which endangers drinking water sources” as that phrase is further defined by the statute. 8 Such programs, at a minimum, must “prohibit any underground injection ... which is not authorized by a permit,” 9 and such permit programs must require a showing to the satisfaction of the state that the underground injection will not endanger drinking water sources....” 10 Underground injection “endangers drinking water sources if such injection may result in the presence in underground water which

6 42 U.S.C. §300h, et seq . Geologic sequestration of CO 2 clearly meets the definition of underground injection found at 42 U.S.C. §300h(d)(1), “the subsurface emplacement of fluids by well injection.” Carbon dioxide, whether injected in a supercritical state, or as a gas, meets the definition of a fluid included in the existing regulations under

the SDWA: those rules state that a “fluid” is “ any material or substance which flows or moves whether in a semisolid, liquid, sludge, gas or other form or state.” 40 CFR § 144.3.

7 While our Environmental NGO Group agrees that EPA’s primary authority for the promulgation of this rule is found in the Safe Drinking Water Act, we also point out above that the Clean Air Act authorizes controls on CO 2 emissions that necessarily implicate and necessitate this UIC approach, and so also can be said to provide authority for Class VI rules. EPA must exercise its Clean Air Act authority to regulate CO 2 for the purposes of preventing its release to the atmosphere. Additionally, and more generally, EPA could also promulgate verification and accounting protocols for CO 2 GS, as needed, under those Clean Air Act rules. Such Clean Air Act rules may or may not prove adequate for purposes of any future legislatively created trading system. Clearly, however, the UIC rules should not be regarded as sufficient to authorize or certify carbon credits as part of such a system, as they do not provide sufficient proof that CO 2 will be permanently sequestered from the atmosphere, nor do they include additional details necessary for verifying and quantifying any atmospheric releases.

8 42 U.S.C. §§ 300h(a)(1), (b)(1).

9 Id . § 300h(b)(1)(A).

10 Id . § 300h(b)(1)(B).5 supplies or can reasonably be expected to supply any public water system of any contaminant, and if the presence of such contaminant may result in such system’s not complying with any national primary drinking water regulation or may otherwise adversely affect the health of persons.” 11 And “contaminant” is defined as “ any physical, chemical, biological, or radiological

substance or matter in water.” 12 Underground injection furthermore is prohibited without a permit, and to receive a permit the applicant must demonstrate that endangerment “will not”

occur. 13 This preventive, broadly scoped language demonstrates that Congress intended that all underground injection be regulated under the UIC program. 14

The statute provides additional direction to EPA in developing its rules – the rules must “permit or provide for consideration of varying geologic, hydrological, or historical conditions, in different States and in different areas within a State,” 15 and they are not to “interfere with or impede” underground injections for the purposes of “the secondary or tertiary recovery of oil or natural gas, unless such requirements are essential to assure that underground sources of drinking water will not be endangered by such injection.” 16 While EPA is not free to exempt a particular class of injection entirely from rulemaking, the Agency is authorized to tailor the UIC rules to the specific geologic conditions and also to particular injection activities. The statute clearly authorizes EPA to create a new class or classes of UIC wells for the purpose of CO 2 sequestration.

This precautionary, forward looking statutory purpose and structure authorizes EPA also to take an adaptive approach, both in rulemaking and in defining permit terms, specifically to direct states to be adaptive in monitoring, tracking, and updating permits, in order to reflect lessons learned from experience and from monitoring reports. The statute also authorizes EPA to take an adaptive approach to the rules themselves. Section 1421(a)(1) states that “any regulation [governing underground injection activities] may be amended from time to time.” 17 Whereas, as is the case with EPA’s proposed Class VI rules, regulations are established to govern a system on a scale of deployment that has not yet been demonstrated 18 , the preventive and precautionary nature of the UIC statute demands a periodic review, assessment, and update of the rule. EPA should, in its final rule, declare its intention to undertake such a process. Moreover, our Environmental NGO Group recommends that EPA commit itself to issuing a Notice of Proposed Rulemaking by no later than an identified date, perhaps in 2020, which would formally initiate this process.

11 Id . § 300h(d)(2).

12 42 U.S.C. § 300f(6).

13 42 U.S.C. § 300h(b)(1)(A), (B).

14 See also NRDC v. EPA , 824 F.2d 1258, 1271 (1 st Cir. 1987), holding that Congress intended the phrase ‘underground injection which endangers drinking water sources" should have the broadest applicability, and citing and quoting H.R. Rep. No. 1185, 93d Cong., 2d Sess., reprinted in 1974 U.S. Code Cong. & Admin. News at 6484.

15 42 U.S.C. § 300h(b)(3)(A).

16 Id. § 300h(b)(2)(B).

17 42 U.S.C. § 300h(a)(1).

18 Although the practice of injection/GS has been demonstrated at the individual project scale.6 

### C. The Proposed Rule Has Many Positive Features

Before offering comments on the proposal itself, we want to praise and lend our support to EPA for incorporating, or in some cases intending to incorporate, a number of features of the rule that we regard not solely as desirable, but essential. These include:

• specific requirements for a comprehensive characterization before deeming a sequestration site as appropriate for injection;

• monitoring requirements for tracking the behavior and location of CO 2 in the subsurface, validating its confinement, or detecting unwanted behavior early to allow for corrective action;

• the need to compile a monitoring plan, a site care and closure plan and a remedial response plan prior to obtaining a permit;

• the requirement to update and report on these plans, including the area of review adjustment process, as monitoring and operational data become available;

• a requirement for a continuous feedback loop between monitoring and modeling, whereby one updates the other in order to optimize operations and refine simulations; and

• a criterion for site closure that is not based on the mere passage of a set number of years, but on the finding that drinking water is not endangered and that the project meets the necessary performance standards (we note, however, that articulation of the performance standards that need to be met in order to make such a finding is one of the areas where the rule needs work).

These features are captured to differing extents by the proposed rule’s language, and our suggested changes below serve to reinforce these features. Some of these features appropriately go beyond what is currently required under existing well classes in the UIC program. We regard them as necessary for the effective regulation of GS in the Class VI context, and strongly support them. We would therefore label our proposed changes as technical modifications, and not radical changes in the rule. Even though these strengthening changes are needed, we urge EPA to maintain the basic structure of the rule as proposed and thank the drafting working group for producing the proposed rule in a short timeframe.



### D. General Comments

Timing of promulgation

The proposed rule is based on a risk management approach and is written in a way that should avoid unintended consequences to USDWs. It is important to bear in mind that CO 2 injection projects can already be permitted today. While this may be adequate to protect USDWs in certain cases, it is in the interests of the public (and the regulated industry) to have a new injection class, designed from the outset with the particular characteristics of GS in mind, as soon as possible. This is necessary in order provide certainty and adequately safeguard public health and the environment. If the final rule incorporates changes concerning the adaptive nature of the rule and permits, as our Environmental NGO Group suggests, the Agency, and its state counterparts, will be able to deal with such unintended consequences to USDWs through the rule’s performance-7 based provisions, review and a possible reissuance of permits if necessary, and by revising the rule text if appropriate.

We consider the Phase III Deployment Phase of the Department of Energy’s (DOE) Regional Partnership Program to be very worthwhile, but we do not consider the completion of this program to be a prerequisite for either commercial implementation of CCS or for the promulgation of a sound and protective rule. The DOE’s program has limited funds available through appropriations, and its demonstration projects will be of limited scale and duration. In addition, it focuses as much or more on the optimum way to apply existing technologies as it does on fundamental research or even demonstrations that particular technologies “work.” Our scientific and practical understanding and experience in GS itself, as well as in related underground injection activities, is sufficient to construct and operate the first large-scale, commercial plants in the U.S., provided they are regulated adequately. In that respect, we do not consider the proposed rule premature, but a very timely and necessary development.

The rule itself, rather than individual permits , should assure that Class VI permits do not allow responsible parties to avoid CERCLA liability on grounds that a release constitutes a “federally permitted release”

EPA notes in the preamble to the proposed rule (73 Fed. Reg. 43504) that CERCLA exempts from liability certain “federally permitted releases, including releases in compliance with a UIC permit under the Safe Drinking Water Act.” EPA further notes that “Class VI requirements and permits will need to be carefully structured to ensure that they do not ‘authorize’ inappropriate hazardous releases.” Our Environmental NGO Group strongly urges EPA to go further and effectively prohibit Class VI permit conditions that would make the “federally permitted release” defense available should injected fluids or displaced formation fluids enter or endanger USDWs. We suggest that such a prohibition be added to Subpart E – Permit Conditions, or to any other section of the rule that EPA finds appropriate.

The rule should incorporate a “n on-interference principle” to keep one sequestration project from interfering with the effectiveness of another

As EPA notes in the preamble (page 43506), “it is ... possible that multiple owners or operators will be injecting CO 2 into formations that are hydraulically connected and thus the elevated pressure zones may intersect or interfere with each other.” Our Environmental NGO Group agrees that this is a genuine possibility at this stage in GS implementation. Until comprehensive approaches to basin-scale management are developed, we urge the adoption of the following addition to §146.94:

“(e) If an owner or operator obtains evidence that a pressure front associated with one geologic sequestration project intersects or threatens to intersect a pressure front associated with any other project, the owner or operator obtaining such evidence must notify the Director and the other owner or operator. If the Director determines that the pressure front associated with one project interferes or8 threatens to interfere with the ability of a project that began operations at an earlier date to sequester the earlier project’s total anticipated volume of the carbon dioxide stream as determined under §146.83(a), the Director may require the owner or operator of the project that began operations at a later date to modify operations as necessary to avoid such interference. “

Process for permit review by experts

We recommend that EPA consider establishing a process to collect input from experts to help inform EPA and states on evolving GS technology and appropriate policy and regulatory responses. Participants in the process should be independent, non-partisan, unbiased experts in the field, We recommend that the participants not be convened under the Federal Advisory Committee Act. Their opinions would be non-binding. Obtaining such input would help regulators improve their permitting decisions and would be complementary to the objectives of increased funding and resources for the UIC Program, outlined below.

Funding and resources for the UIC Program

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 addressing 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 agencies 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 regional agencies are asked to take on

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

Significant additional resources will need to be made available to hire new permitting staff and field inspectors. Those new staff, along with existing UIC staff, must be trained in subjects that will enable them to make prudent permitting, management, and oversight decisions. EPA and states will need to be adequately prepared to review applications and make permitting decisions.Failure to provide sufficient resources will likely create permitting backlogs or result in suboptimal permits being issued.

The Ground Water Protection Council (GWPC) estimated in 2004 that an annual funding increase to $56 million would be needed just to meet the needs of the existing UIC program at the state level even without the addition of GS project permitting. 19 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.

19 GWPC, Class V Resource Needs Survey, Summary (September 2004).9 Public Water Systems should receive notice of permit applications and have the opportunity to participate in the permitting process

EPA should adopt the existing requirements for public participation at 40 CFR Part 25 and 40 CFR Part 124 as suggested in the proposal. UIC Program Directors should also incorporate modern communication technologies (cable television, various internet tools) to increase the likelihood of effective public understanding and involvement. Engaging the public as soon as

candidate locations are identified will also increase the effectiveness of the effort. Given the focus of the rule on preventing harm to USDWs, UIC Program Directors should work with primacy agencies and departments with responsibility for implementing other aspects of SDWA to identify and notify Public Water Systems (PWSs) with a potential interest in the project. PWSs are an important stakeholder in the projects and should be the focus of targeted outreach at every stage of the permitting process. PWS representatives should be invited to serve on any Advisory Groups or other bodies set up during the lifetime of the project. We suggest that in Guidance to accompany this rulemaking, EPA urge owners and operators to establish on-going relationships with potentially impacted PWSs.

Pressure limits

We believe that the pressure management provisions in §146.88(a) require modification. The members of our Environmental NGO Group have not reached agreement on the exact language for the suggested changes and are either submitting individual comments on this issue or are submitting comments jointly with other groups. We do agree, however, that injection pressure limits must be established after adequately considering the risks of both tensile failure and shear failure in the confining zone. We also agree that limits must be designed to avoid causing otherwise non-transmissive faults to become transmissive, in addition to addressing the more traditional concern of avoiding the initiation or propagation of fractures.

Site closure standards and framework for long-term stewardship

Our Environmental NGO Group did not come to a common set of recommendations on site closure and are either submitting individual comments on this issue or are submitting comments jointly with other groups. We do agree, however, that EPA’s proposed closure standards in §146.93 need revision. In order to assure that site risks have diminished to the point that it is reasonable to discontinue or significantly reduce monitoring, it is essential that the rule require a demonstration of much more than merely ‘plume stabilization’ and that the nature of what must be demonstrated be precisely described. In addition, given the desired permanent nature of CO 2 sequestration in the subsurface and the importance to the public of ensuring long-term oversight of project sites, EPA should use its existing regulatory authorities to establish a framework for long-term stewardship and seek whatever additional authorities may be required for this purpose from Congress. This framework should include an entity with responsibility for monitoring and managing sites after closure has been authorized. The proposed rule authorizes operators to stop monitoring, but does not provide for the stewardship of sites following closure.. EPA must rectify this omission. It is important that the post-closure framework include financing provisions that are adequate to ensure proper site stewardship in the long-term.10 

### E. Specific Amendments to the Proposed Rule

The rule should authorize Class VI permits for “up to” the operating life of a facility only if the rule is amended to require all aspects of project operations to be modified as appropriate over the course of the project

We support EPA’s proposal in §144.36 to issue Class VI well permits for a period “up to” the operating life of the facility. Still, it is not appropriate to issue these permits for the full operating life of the facility without consideration how project performance is evolving. Revisions of the Area of Review, and the various plans outlined in the proposed rule are to be expected from time to time, and it is possible that some of the needed revisions might be so material so as to constitute ground for modification, revocation or reissuance of the permit.

Class VI is appropriately grouped with Class I Hazardous, Class II and Class III wells in the modification or revocation and reissuance provisions

We believe that EPA in §144.39 has appropriately listed Class VI alongside other injection classes for which a permit can be revoked and reissued for a specific cause (alterations to the facility, new information received and regulatory changes since the permit issued. This is necessary in order to ensure that Class VI regulations are adaptive, reflecting experience in GS as it is amassed. We do not support Class VI being listed alongside classes for which the permittee has control over whether reissue or modification would occur through requesting or agreeing to

it.

The definition of “carbon dioxide stream” should not be restricted to CO 2 captured from

industrial sources

The definition of “carbon dioxide stream” in §146.81(b) includes only carbon dioxide “that has been captured from an emission source (e.g., a power plant).” Over time, the vast majority of sequestered CO 2 is likely to be captured from such sources, but rules are also needed to govern the sequestration of naturally occurring CO 2 produced from geologic formations. We suggest

that the definition be revised to read as follows:

“Carbon dioxide stream means that has been captured from an emission source (e.g., a power plant), carbon dioxide plus incidental associated substances derived

from the source materials of the CO 2 and/or the capture process, and any substances added to the stream to enable or improve the injection process. This subpart does not apply to any carbon dioxide stream that meets the definition of a hazardous waste under 40 CFR part 261.”

Class VI applicants should be required to identify all known wells penetrating formations affected by increased pressure11 In proposed §144.55(a) the rule would require Class I, II (other than existing), III or VI permit applicants to identify the location “of all known wells within the injection well’s area of review which penetrate the injection zone” or, in the case of Class II wells operating over the fracture pressure of the injection formation, “all known wells within the area of review penetrating formations affected by the increase in pressure”.

Since injection in deep saline formations will result in an area of elevated pressure (above the original reservoir pressure) that will be larger than the CO 2 plume and could affect overlying or underlying formations, we believe that the latter requirement for Class II wells operating above the fracture pressure should also apply to Class VI wells. This would help prevent the unwanted migration of reservoir fluids from outside the injection zone through existing wells in the confining zone, as a result of the pressure increase. We therefore suggest that §144.55(a) be

revised to read as follows:

“ Coverage . Applicants for Class I, II, (other than existing), or III, or VI injection well permits shall identify the location of all known wells within the injection well's area of review which penetrate the injection zone. In the case of Class II wells operating over the fracture pressure of the injection formation, applicants shall identify the location of all known wells within the area of review penetrating formations affected by the increase in pressure. Applicants for Class VI shall identify the location of all known wells within the area of review penetrating the injection zone and all known wells which penetrate formations affected by the increase in pressure and shall perform corrective action as specified in Sec.

146.84.”

The rule should explicitly exclude from Class VI efforts to sequester CO 2 in basalts, coal seams, salt caverns and shales, which instead sh ould be regulated under Class V Experimental

We believe that EPA has ample basis for adopting rules to regulate geologic sequestration in hydrocarbon reservoirs and in deep brine formations. For these types of geologic formations, there is a widespread technical consensus on how to assess and manage risks, what data is needed to characterize sites, how to select sites, how to conduct injection operations, how to

model the behavior of CO 2 in the reservoir, and how to monitor project performance. There is no such consensus, however, regarding sequestration in basalts, coal seams, salt caverns and shales. The trapping mechanisms of CO 2 and/or the operational engineering involved in such operations is significantly different to those in deep saline formations and hydrocarbon reservoirs, and using identical regulatory language would be ill advised. In fact, it is not known at this time whether sequestration (or even injection in some cases) can even be done at scale in such formations – efforts in these formations are very much still in the experimental stage. There is no basis at this time for determining whether rules that are appropriate for wells in hydrocarbon reservoirs and deep saline formations are also appropriate for wells in these other formations. Until there is better understanding of whether and how sequestration can be safely accomplished in basalts, coal seams, salt caverns and shales, wells in these formations should be treated as experimental

wells under Class V.12 Projects designed to evaluate injection in coal seams, salt caverns and shales should be permitted under the UIC Class V provisions and subject to the March 2007 Guidance on “Using the Class V Experimental Technology Well Classification for Pilot GS Projects. 20 This Guidance clearly states that Class V is intended only for projects “...designed to evaluate the technical issues

associated with CO 2 injection” 21 . The Director should review all Class V GS permit applications to insure that they meet the definition of Pilot Project in CFR 146.3: “... a technology which has not proven feasible under the conditions in which it is being tested.” The purpose of such pilot projects should be to gather and share information which will lead to a clearer understanding of the feasibility of such projects on a commercial scale.

In order to implement our suggestion regarding these formations, we recommend revising sections 144.6(f), 144.80(f), 146.5(f) and the definition of sequestration in §146.81 accordingly. We suggest retaining the provision in proposed §144.15 that the construction, operation or maintenance of any non-experimental Class V geologic sequestration well is prohibited.

The rule should not prohibit in a blanket fashion GS sites located above the lowermost USDW, but should permit such sites only under certa in conditions that are not applicable to sites

below the lowermost USDW

We believe that GS sites located above lowermost USDWs may or may not present more types of risk than sites located below lowermost USDWs, but that in any event the consequences of leakage from sites above USDWs are likely to be more significant in the event that leakage occurs. At the same time, we recognize that there many potentially excellent sequestration sites above USDWs and that in some areas these may be the only sites available. We believe the rule should authorize GS sites above lowermost USDWs only if such sites meet requirements that go beyond what is mandatory for other sites. The following additional conditions would need to be

satisfied:

• confirmation that there is a confining zone underlying the entire base of the injection

zone;

• mandatory monitoring for changes in groundwater chemistry above the upper confining zone and below the lower confining zone; and

• prior to permit issuance, and as a condition of permit issuance, completion of regional hydrogeologic studies that are conducted with sufficient accuracy to simulate regional hydrologic flows and demonstrate that USDWs would not be endangered if injected or formation fluids were to move beyond either the higher or the lower confining zone.

Emergency and remedial respon se, including response to potential problems relating to geologic features, is a necessary complement to corrective action and should remain in the

rule

20 UICPG#83

21 Id. at p. 113 While wells are the most likely conduits for fluid movement into USDWs, the definition of corrective action and the relevant provisions in §146.84 do not take into account the potential for geologic features, such as faults, spill points or fractures, to act as conduits for CO 2 or other fluid migration, and hence breach of confinement. Actions to mitigate or remediate a potential breach of confinement, or a situation which might eventually lead to a breach of confinement, should not be limited to corrective action on wells. We therefore strongly support EPA’s inclusion of the Emergency and remedial response section. We propose two minor changes – change §146.94(b)(4) to read:

“Implement the emergency and remedial response plan approved by the Director, and keep him apprized of the implementation .”

and §146.94(d) to read:

“The owner or operator must notify the Director and obtain his approval prior to conducting any well workover or other remediation measures not listed in the emergency and remedial response plan .”

The definition of “confining zone” should not be limited to formations overlying the injection zone, and should focus on limiting movement through the confining zone rather than out the injection zone

The proposed definition of confining zone in §146.81(d) requires that the formation act as “a barrier” to fluid movement, which may be unnecessarily strict. The definition also fails to recognize that it is movement through and beyond the confining zone that needs to be limited. We suggest instead that the definition of “confining zone” read as follows:

“Confining zone means a geologic formation, group of formations, or part of a formation stratigraphically overlying the injection zone that acts as a barrier to

limit fluid movement beyond this formation, group of formations, or part of a

formation .”

The second sentence of the definition of ‘geolo gic sequestration project” should be amended to refer more generally to formation fluids and be transferred to the definition of “area of

review”

We suggest the following amendment to §146.81(d) in order to be more inclusive on the types of fluid that could be displaced:

“[...] It includes the subsurface three-dimensional extent of the carbon dioxide plume, associated pressure front, and displaced brine formation fluids , as well as the surface area above that delineated region.”14 We also suggest that this second sentence of the definition of geologic sequestration project be transferred to the definition of area of review as recommended above. The language provided above reflects the change from “brine” to “formation fluids.”

Moreover, we suggest that the present restriction of Class VI to formations below the lowermost USDW is more appropriately addressed elsewhere. Accordingly, we recommend that geologic sequestration project be defined as follows:

“Geologic sequestration project means an injection well or wells used to emplace a carbon dioxide stream beneath the lowermost formation containing a USDW into an injection zone for geologic sequestration . It inc ludes the subsurface three

dimensional extent of the carbon dioxide plume, associated pressure front, and displaced brine, as well as the surface area above that delineated region. ”

The term “pressure front” should be replaced with the more accurate term “area of elevated pressure” throughout the rule

The term “pressure front” in 146.81(d) is likely to be scientifically inaccurate as it implies a front, or discontinuity in pressure, whereas in reality there will be a continuous pressure gradient in the formation in most cases. We suggest globally replacing “pressure front” with “area of elevated pressure” throughout the rule.

Additional well identification methods that do not rely on the public record should be required in certain provisions

§146.82(b) requires a map to be submitted with the permit that shows wells within the area of review – only information of public record is required to be included on this map. §146.82(e) requires a tabulation of all wells within the area of review which penetrate the injection or confining zone(s), including information on the well’s type, construction, date drilled, location, depth, record of plugging and/or completion and any additional information that the Director may require.

While we are comfortable with relying on information of public record in subsection (b), we believe that additional diligence is needed when it comes to wells that penetrate the injection or confining zone in subsection (e). Information of public record is often incomplete and/or inaccurate. There are numerous orphaned or abandoned wells that are not listed on the public record that could potentially affect the integrity of the confining zone. While generally it is possible to intercept these problems during operations, there are methods available today to identify wells not listed on the public record 22 , which in many cases could identify potentially problematic wells in advance. A requirement to supplement public record information with field measurements should be included in the rule, and described with a term that is broader than “tabulation” in order to allow the Director to require other data formats as needed :

22 NETL , for example, has developed an electromagnetic system that can be used for areal or ground-based identification of wells (casings).15 §146.82(e): “A tabulation compilation of all wells within the area of review which penetrate the injection or confining zone(s). To supplement and/or verify information of public record, operators shall use reasonable methods to identify the presence wells within the area of review that penetrate the injection or confining zone(s). Such data must include a description [...]”

Additionally, we believe that problematic wells may not be limited to the confining zone, as would be the case if confinement were to be breached, or if pressure effects caused by the injection caused fluid movement outside the defined confining zone. We recommend the following modification in §146.84(c)(2):

“Using methods approved by the Director, identify all penetrations, including active and abandoned wells and underground mines, in the area of review that may penetrate the confining zone or otherwise act as conduits for fluid movement inside or outside the confining zone ”.

The term “transmissive fault or fracture” should be clarified

The proposed rule in §146.83(a)(2) requires a confining zone(s) that is free of transmissive faults or fractures, while §146.81 defines this term as “A fault or fracture that has sufficient permeability and vertical extent to allow fluids to move between formations”. We suggest the following modification to the definition in §146.81(d) in order to avoid unduly restricting movement that is merely between formations (compare our comments above on the definition of “confining zone”):

“Transmissive fault or fracture means a fault or fracture that has sufficient permeability and vertical extent to allow fluids to move between for mations beyond a confining zone .”

Secondary confining zone

§146.83 allows the Director to require additional confining zones, at his discretion. We do not believe that this will always be necessary – a good primary zone should be sufficient. Where additional hazards justify it, a secondary zone might be desirable. In all cases, we caution against relying on secondary confinement in place of establishing with a greater degree of certainty the suitability of the primary zone. Potential problems are best identified and anticipated early, and the focus should be on site characterization to show with confidence whether the confining zones are adequate. We suggest striking part (b) in §146.83 as it seems redundant. However, the Director must have the discretion to require a secondary confining zone if needed. We therefore recommend clarifying part (a)(2) to read explicitly:

“A confining zone, or zones, that is are free of transmissive faults or fractures and of sufficient areal extent and integrity to contain the injected carbon dioxide16 stream and displaced formation fluids and allow injection at proposed maximum pressures and volumes without initiating or propagating fractures in the confining zone(s)”

The area of review provisions should be revised in several respects

Surprisingly, the definition of “area of review” (AOR) in §146.81(d) fails to mention that elevated pressure a critical aspect of what it means for an area to be “impacted” by injection activity. Our Environmental NGO Group recommends borrowing language from the proposed definition of “geologic sequestration project” and reworking the “area of review” definition.

An additional concern is that both §146.81 and §146.84(a) state that the AOR is “based on computational modeling”. This could imply that the Area of Review could be based solely on computational modeling. Instead, the AOR should be based on computational modeling, monitoring and operational data (and kept updated until closure is approved). All references to computational modeling in relation to the Area of Review in this section, as well as in the definition of Area of Review in §146.81 should be amended as appropriate to read “based on computational modeling, as well as monitoring and other operational data.” We urge that the

definition be revised as follows:

“Area of review means the area that may be impacted by the injection activity. The area of review is based on computational modeling, as well as monitoring and other operational data, that account for the physical and chemical properties of allphases of the injected carbon dioxide stream. It includes the subsurface threedimensional extent, throughout the operating life of the facility, of the carbon dioxide stream plume, associated pressure front, and displaced formation fluids, as well as the overlying formations and surface area above that delineated region.”

Even though proposed §146.84(f) requires “reevaluation” of the AOR at a “minimum” fixed frequency of ten years or “when operational and monitoring conditions warrant” (the “and” should be an “or”), §146.84 runs the risk that revisions will not be made on a timely basis. Default periods have a way of becoming the standard way of doing business. We recommend imposing a continual obligation on operators to assess whether the AOR should be revised, a requirement for an annual report stating whether circumstances during the preceding year warranted a revision, and a requirement that revisions be done when required by the Director as well as when the operator determines that conditions warrant. To accomplish this, it will be useful to break down the concept of “reevaluation” into two ideas – “assessment” of the need to revise the AOR and the actual process of “revision.” There are several portions of §146.84 that will need to be changed in order to incorporate these suggestions. We believe that these suggestions will incentivize honest and truthful reporting of data and site performance while avoiding the excessive burden of “re-evaluating” or revising the Area of Review if such work is not needed. Moreover, a continuous obligation to assess whether revisions are needed, when coupled with the annual reporting requirement just suggested, w ill create a clear accountability trail for both operator and Director in case of disputes.17 The rule should require updating when warranted of all of the proposed “plans” and should require an annual report that summarizes whether not updates have been warranted, and whether or not updates have been undertaken

We applaud EPA for proposing to require the creation, use, and updating of various “plans” during the operating life of a facility. By creating such an iterative process, and basing it on monitoring and other operational data that become available through time, EPA can assure that facilities are managed in a way that adapts to changing circumstances. This approach also has the potential to enable what the Preamble calls an “ongoing dialogue” between operators and regulators, especially if the rule is enhanced by the annual reporting requirement suggested below for inclusion in §146.91.

Perhaps inadvertently, the proposed rule does not explicitly require updating of several of the required plans. In most but not all cases, there is a rather ambiguous requirement to “maintain” a given plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the testing and monitoring plan required by §146.90 (the ambiguous word “maintain” is used and there appears to be no requirement that estimated plugging costs be kept current);

• the plugging plan required by §146.92 (again the ambiguous word “maintain” is used);

• the post-injection site care and site closure plan required by §146.93 (not only is the word “maintain” used, but the ambiguity inherent in this term is revealed by the instruction in §146.93(a)(3) to consider amendments to this plan “upon cessation of injection” – §146.93 might be read to mean that operators could “maintain” this particular plan simply by considering the need for amendment on one occasion over the life of the facility); and

• the emergency and remedial response plan required by §146.94 (there is no requirement here that the plan be updated as warranted – there is not even a requirement that the plan be “maintained.”

An additional annual reporting requirement will enhance the ability of both Director and operators to keep track of which plans require updating and whether or not plans that ought to be updated have in fact been revised. Such a shared understanding is essential if there is to be the “ongoing dialogue” between regulators and operators that EPA anticipates. Our Environmental NGO Group considered supporting the inclusion of an annual report as described in the preamble at 73 Fed. Reg. 43518, but concluded that the benefits of that particular report would be outweighed by the burden. The annual report we are suggesting here, however, would be much simpler. We believe that EPA should require a report, signed by the appropriate company official, that:

• lists all of the required plans;18 • confirms for each plan that the company has reviewed all monitoring and operational data since the previous annual report that is relevant to a decision on whether to update the plan;

• states with regard to each plan whether an update was determined to be warranted;

and

• for those plans where the operator did decide that an update was appropriate, a statement that the update has or has not been completed and a summary of the

modifications that have been made.

The rule should further provide that the Director has authority to require submission of copies of updated plans and/or further information regarding the reasons why updates of particular plans

have or have not been done.

Cementing requirements for casings

§146.86(b)(3) requires the long string casing to be cemented by circulating cement to surface in one or more stages. It has come to our attention that may be hard to accomplish in some cases, such as very deep wells. We have also been alerted to disadvantages of this approach with regard to the weight of the cement column and its relation to well integrity. We urge EPA to fully consider the advantages and disadvantages of this approach. At a minimum however, the long string casing should be cemented to at least above the confining layer (caprock).

Cement bond logs and other outdated methods are not sufficient for establishing cement quality and integrity

Some of the techniques listed in §146.87(a)(2)(ii) and §146.87(a)(3)(ii), such as cement bond and variable density logs are no longer state-of-the-art, and do not reveal the nature or shape of any voids in the cement – instead they represents an average estimate of void space. To verify the integrity of cement behind casings, including the location of any channels, contamination or missing cement, the Director should require “a cement map that incorporates data from a cement bond log, a variable density display, and an ultrasonic image, unless an alternative evaluation based on equivalent or better technologies has been approved in writing”.

Monitoring

In §146.90 the proposed rule outlines requirements for testing and monitoring. We strongly support the inclusion of such provisions. Monitoring is central to verifying and adapting the operational parameters of a GS project, while the concept of GS cannot be simply based on the premise of confinement without verification. We also support the provisions calling for a testing and monitoring plan, although we have suggested above that the requirements for updating this plan be strengthened. The collection of baseline data and information prior to the commencement of operations is also necessary for a number of monitoring techniques to produce useful results, and should be preserved.19 The proposed rule outlines several different types of monitoring requirements: (a) analysis of the

CO 2 stream; (b) continuous monitoring of injection pressure, rate and volume as well as other quantities; (c) corrosion monitoring for the well materials; (d) groundwater and geochemistry monitoring above the confining zone; (e) mechanical integrity testing; (f) pressure fall-off tests; (g) CO 2 plume and pressure front tracking; and (h) surface air monitoring.

We do not wish to comment on (c). We consider subpart (i), enabling the Director to require additional forms of monitoring, as well as subpart (j), calling for a quality assurance and surveillance plan, entirely appropriate. We consider (a), (b), (d), (e), and (f) and (g) to be essential elements of a sound monitoring system.

In particular, monitoring above the caprock, sometimes informally referred to as “above-zone monitoring, and covered in (d), is a tested monitoring method 23 , and one that can be key to verifying the integrity and lateral extent of the caprock (or confining zone). We support its inclusion, but also recognize that it might not be necessary to employ this method every time. We would only consider its omission acceptable only if another method capable of testing and verifying the integrity of the confining zone is being used. Subpart (d) would also cover groundwater monitoring near the surface, at a long distance from the caprock. It is our understanding that researchers from the Lawrence Livermore National Laboratory are already confident in the merits of this approach and its accuracy in detecting small amounts of CO 2 . We therefore recommend the following minor changes to §146.90(d):

“Periodic monitoring of the ground water quality and geophysical, geochemical or

other changes above the confining zone(s) that may be a result of carbon dioxide

or other induced fluid movement through the confining zone or additional identified zones; provided however that the Director may instead require the inclusion of other methods that test and/or verify the integrity of the confining zone(s) with similar accuracy and to the same or larger areal extent. (1) [...]”

We also strongly support monitoring to track the CO 2 plume. There is no unique method for doing this, and we do not believe that 4D-seismic techniques are appropriate or effective in all geologic settings, or that they should be made mandatory. However, tracking the extent of the

CO 2 plume is generally possible and must be part of a comprehensive and credible monitoring plan and a GS project. Appropriate limits of accuracy will be needed, as neither tracking

individual CO 2 molecules, nor to the nearest inch are feasible or desirable. However, the monitoring resolution must be such so as to enable confinement to be established, to give regulators confidence that the CO 2 and displaced fluids are not near potential leakage pathways, and to warn in advance of any remedial action that might be needed.

The “position of the pressure front” is not something that is as straightforward to establish as the

extent of the CO 2 plume. As we have commented above, there is no distinct “front”, or discontinuity, but rather a gradient in pressure that dissipates with distance away from the injection zone. Estimating the total injection footprint therefore will require appropriate

23 Used successfully at the Frio pilot project, and already being considered for other projects.20 thresholds to be defined in order to estimate the area of elevated pressure. Additionally, methods such as seismic surveys do not work in the same way for compressed brine as they do for CO 2 - rich brine. Tracking the extent of the CO 2 plume is generally possible and must be part of a comprehensive and credible monitoring plan and a GS project. The extent of the area of elevated pressure will likely be estimated with a combination of measurements, inferences and modeling, but it is presently essential to have monitoring wells penetrating the confining zone to do this.

Where the CO 2 plume itself is concerned, rather than the area of elevated pressure, the role of measurements (including indirect measurements such as seismic surveys) will and should be far greater than that of modeling.

Finally, surface air monitoring techniques will not always be necessary for GS projects. As with other monitoring methods, they may work well in particular settings but not in others (for example where distinguishing from natural variability or from baseline data is hard). Current scientific thinking also dictates that the CO 2 plume and confinement are best monitored near the injection zone or right above the caprock. This implies far greater depths, and a much larger

distance between CO 2 and displaced fluids from USDWs. The Director should have the discretion to require such techniques, but we do not believe that they should be made mandatory for all permits nor should the rule be limited to listing specific techniques (which might be superseded or have preferable alternatives).

To capture the points made above and resolve current inaccuracies or limitations in the proposed language, we recommend the following additional changes in §146.90(g):

“(1) Testing and monitoring to track establish the extent of the carbon dioxide plume and the position of the pressure front within defined thresholds, with the assistance of modeling tools where appropriate and through direct measurements or indirect, geophysical or other techniques by either monitoring for pressure changes in the first forma tion overlying the confining zone or using indirect, geophysical techniques (e.g., seismic, electrical, gravity, or electromagnetic surveys and/or down

- hole carbon dioxide detection tools) ; (2) Testing and monitoring to establish the extent of the area of elevated pressure through direct measurements and the assistance of modeling tools. ”

and in §146.90(h):

“At the Director’s discretion, surface air monitoring methods and/or soil gas monitoring to detect movement of carbon dioxide that could signal endangerment

of

a USDW. (1) The testing and monitoring plan must be based on potential vulnerabilities within the area of review; (2) The monitoring frequency and spatial distribution of surface air monitoring and/or soil gas monitoring must reflect baseline data and the monitoring plan must include how the proposed monitoring will yield useful information on the area of review delineation and/or compliance with standards under 40 CFR 144.12”21 Seismicity

Naturally occurring seismicity has been cited as an area of concern for geologic sequestration of

CO 2 . We do believe that seismicity merits diligent treatment both in the regulations and in project operation, but we see no need for a blanket ban of sequestration in seismically active areas. Although some sites – especially ones near major active faults – would not be advisable for injection, there are plenty of other sites in seismically active areas that would make excellent candidates for safe and effective sequestration. Moreover, tools to measure, predict and design against the effects of seismic activity are available.

Nature has proven its ability to retain fluids trapped in the subsurface in seismically active areas in many instances over hundreds of millions of years, even in highly tectonically active regions of the country such as California. The potential for slippage for faults to create leakage pathways to USDWs or the surface can be managed and effectively minimized through careful siting and operational design using well-established tools and methods. The regulations should ensure that suitable sites are selected, while high risk areas, such as those near major, non-sealing faults or those that demonstrate frequent activity, are rejected. The most likely potential CO 2 leakage paths would be injection wells, and not faults. However, these can be designed to prevent leakage and to be resilient to earthquakes.

We regard a ban on sequestration in seismically active areas unwarranted. We do however believe that additional diligence is required in site characterization and selection in such areas. The requirement in §146.82(c)(3) should be modified as follows:

“Information on seismic history including the presence and depth of seismic

sources and an assessment of that whether such seismicity would not interfere with containment;”

In addition, language should be added to the minimum criteria for siting in §146.83, clarifying that if induced or natural seismicity poses unacceptable risks, a permit will not be granted. In order properly to assess the risk of significant induced seismicity in light of permitted operating conditions, the rule may need to require applicants to submit information beyond what is currently required in proposed §146.82. The effects of any seismic events during project operation should also be taken into account when updating, or considering whether to update, the Area of Review and Corrective Action Plan, the Testing and Monitoring Plans, and the Emergency and Remedial Response Plans, as well as any other plans as necessary.



### F. Conclusion

Our Environmental NGO Group appreciates the opportunity to provide comments to EPA on this most important rulemaking effort. A final rule will represent a significant step forward in combating global climate change, and the time is more than ripe for the U.S. to take such steps. When EPA issues its final rule, we feel it must be both technically sound and adaptive to reflect learning from experience with GS projects in as seamless a manner as is possible. We very much look forward to continuing to work with the Agency on this rule, as well as other efforts under22 the Agency’s existing authority to address the significant problem of climate change in the near

term.

Respectfully submitted,

Kurt Waltzer, Clean Air Task Force

Lynn Thorp, Clean Water Action

Scott Anderson, Environmental Defense Fund

George Peridas, Natural Resources Defense Council

John Nielsen, Western Resource AdvocatesLetter ID: 0250

Commenter: Kurt Waltzer Organization: Clean Air Task Force

Letter ID: 0250 Comment ID: 22269 Letter Lines: 68 to 99

Comment Code: 1280 1.1.2.1 General comments on climate change/ global warming

Comment: The planet’s climate is changing fast. Gr eenhouse gas emissions from the use of fossil fuels, mainly carbon dioxide (CO2 ), are having a profound effect on our climate, presenting us with one of the mo st significant environmental and social challenges of the century. In its most recent Assessment Report last year, the Intergovernmental Panel on Climate Cha nge, an independent scientific body, issued the loudest warning to date, calling the warming in the climate system "unequivocal" and calling for serious emi ssion reductions if we are to avoid truly dangerous greenhouse gas concentra tions. Failure to pursue significant reductions in greenhouse gas emissions very soon will make it much harder in the future both to stabilize atmospheric pollu tion concentrations and to avoid the worst impacts of climate change. Climate change is expected to and, indeed, already is having a profound effect on sour ces of drinking water. The American West, for example, is already becoming no ticeable hotter and dr ier, as a recent compilation of studies by the Rocky Mount ain Climate Organization (RMCO) and NRDC summarizes.[FN1]

[FN1: 1 "Hotter and Drier: The West’s Ch anges Climate". Rocky Mountain Climate Organization (RMCO) and the Natural Res ources Defense Council. Available at: http://www.nrdc.org/globalWarming/west/west.pdf]

A growing body of scientific research indi cates that we face extreme dangers to human health, economic well-being, and th e ecosystems on which we depend if global average temperatures are allowed to increase by more than 2 degrees Fahrenheit from today’s levels. We have good prospects of staying below this temperature increase if atmospheric con centrations of CO2 and other global warming gases are kept from exceeding 350 to 450 parts per million (ppm) CO2equivalent. Achieving this goal will require rapid reductions in existing emissions, including action to cut emi ssions by approximately 80% by midcentury. This goal is ambitious, but ach ievable. It can be done through an

annual rate of emissions reductions that ramps up to about a 4% reduction per year. Fortunately, a wide variety of tool s is available today to achieve those

reductions.

Individual Response: GS is one technology in a portfo lio of options, including energy conservation, efficiency improvements, and the use of alternative fuel s and renewable energy sources, that could be deployed to reduce CO2 emissions. Howeve r, the use and promotion of these technologies is outside the scope of the Class VI GS rulemaking. The Class VI GS

1requirements are designed to ensure that, wher e GS is deployed, projects are permitted, sited, constructed, operated, and closed in a manner that protects USDWs from endangerment.

Letter ID: 0250 Comment ID: 22270 Letter Lines: 101 to 120

Comment Code: 1330 1.1.3.1 Support use of GS in general

Comment Code: 1350 1.1.3.3 Comments on the need for GS technology

Comment: While it is not a "silver bullet", one important tool is the geologic sequestration (GS) of CO2 at properly sel ected and properly regul ated sites. Our Environmental NGO Group does not necessarily have a common view concerning the magnitude of the long-term role of GS in combating climate change, but we are united in recognizing that a transition aw ay from fossil fuels will take time and that GS is likely to be an importa nt part of the near- to medium-term solution. Fortunately, capturing CO2 and pe rmanently sequestering it in certain types of well-selected and well-managed ge ologic formations is a technology that is ready to begin deployment today. While GS projects can be permitted today under the Safe Drinking Water Act’s (SDWA) UIC program (in fact a number of projects have already been permitted under existing well classes), the rules that currently apply to such projec ts were not designed with geologic sequestration in mind. Thus, the importance of this rulemaking is not that it is needed in order for GS projects to re ceive permits; rather, the rulemaking is important because it can assure that GS projects are regulated under rules that are specifically designed to require GS projects to be done safely and effectively without endangering undergr ound sources of drinking water (USDWs) or, as discussed below, resulting in a ri sk of release to the atmosphere. For that reason, it is essential that EPA promulgate final rules for GS in a timely manner that are sufficient to protect USDWs.

Individual Response: EPA agrees that GS is one technology in a portfolio of options, including solar, wind, biomass, and geothermal, that coul d be deployed to reduce CO2 emissions; however these technologies are outsid e the scope of the UIC GS rulemaking. The Class VI GS requirements are designed to ensure that, where GS is deployed to address climate change, projects are permitted sited, constructed, operated, and closed in a manner that avoids releases of

CO2 into USDWs.

Please see the remainder of EPA’s responses to th is comment for further details. For additional information on EPA’s final regulatory approach, pl ease see the final rule and preamble as well as the rulemaking docket.

Letter ID: 0250 Comment ID: 22271 Letter Lines: 122 to 139

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

Comment Code: 1420 1.2.1.1 Support the GS rulemaking

2Comment: It is also essential that the U.S. Envi ronmental Protection Agency (EPA) take supplemental action, based on other (non-SD WA) authority, to provide additional assurance that injected CO2 will not be re leased into the atmosphere in a way that adversely impacts the climate or otherwise endangers public health and welfare. Generally, the steps needed to pr otect USDWs are also needed in order to prevent emissions to the atmosphere . Supplemental steps citing additional authority should also guarant ee that CO2 injected into geologic formations stays out of the atmosphere. This should be done according to a permanence (performance) standard, which will certify CO2 as ‘geologically sequestered’ for that purpose, in addition to protecting US DWs. These are needed, as none of the existing or proposed injection classes ar e adequate for the task of certifying CO2 as permanently sequestered for th e purposes of preventing atmospheric releases. In order to be fully protective of the environment, Congress will also need to pass comprehensive cap and trade legislation to control the emission of greenhouse gases from all anthropogenic sources. But the need for such legislation is not a basis for deferring the adoption of EPA rules to protect USDWs or to assure that injected CO2 doe s not result in harmful releases to the atmosphere.

Individual Response: EPA acknowledges that the issue of GS falls within the broader context of CCS, but clarifies that the scope of the GS regulation is limited to injection of CO2, and that all requirements in the GS rule are designed for the purpose of protecting USDWs from endangerment. The SDWA does not provide the UIC Program with the authority to develop regulations for all areas related to GS, such as releases to the atmos phere. "Cap and trade" legislation is outside of the scope of this rulemaking. The UIC requirements are designed to ensure that, where GS is employed, it is done in a manner that protects USDWs from endangerment.

EPA acknowledges that GS falls within the broade r context of CCS and the need for regulatory clarity to ensure that USDWs are protected from endangerment. In develo ping the final GS rule,

the Office of Water coordinated with other Agency program offices and across federal agencies (e.g., with the Department of Energy; United Stat es Geological Survey; Bureau of Ocean Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; Bureau of Land Management). The Agency continues to eval uate areas of potential applicability of other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and Recovery Act; the Comprehe nsive Environmental Response, Compensation, and Liability Act; and the Marine Protection, Resear ch and Sanctuaries Act to various aspects of GS and CCS. The Agency will continue to coordinate on GS and CCS related issues to minimize redundancy and maximize efficiencies for owners or operators. For additional information, please see the discussion entitle d "How Does This Rulemaking Relate to Other Federal

Authorities and GS and CCS Activities?" in the preamble to the final GS rule.

In a separate rulemaking under authority of th e Clean Air Act, EPA is amending the Greenhouse Gas (GHG) Reporting Program at 40 CFR Part 98 to add reporti ng requirements for facilities that conduct GS (subpart RR) a nd all other facilities that in ject CO2 underground (subpart UU).

3For additional information, see the section of the final GS rule preamble entitled, "How Does Mandatory Reporting of Greenhouse Gases (GHGs) Relate to This Rulemaking?” and the GHG Reporting Program rulemaking and docket.

Letter ID: 0250 Comment ID: 22272 Letter Lines: 141 to 167

Comment Code: 1290 1.1.2.2 Comments that EPA should regulate CO2 as a pollutant

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

Comment: The Supreme Court recognized in Massac husetts v. EPA [FN2] that EPA has authority and, indeed an obligation, u nder the Clean Air Act to regulate emissions of greenhouse gases, including CO 2, that "cause or contribute to air pollution that may reasonably be anticip ated to endanger public health or welfare." [FN3] Similarly, the D.C. Circ uit’s remand of the power plant new source performance standards ("NSPS") places EPA in the position to regulate CO2 emissions from new and also existing s ources within that industrial sector. [FN4] The Environmental Appeals Board EAB also recently has rejected the agency’s arguments that it is not author ized to issue best available control technology (BACT) emissions limits for CO 2 in the context of a new source air permit decision for a large new coal-fire d power plant, under the Clean Air Act’s Prevention of Significant Deteriorat ion (PSD) new source review authority. [FN5]

[FN2: 127 S.Ct. 1438 (2007).] [FN3: Id. at 1460-61.] [FN4: Order, NY, et al. v. EPA, D.C. Cir. No. 06-1322 (Sept. 24, 2007). Once NSPS are set for an industry under sec tion 111(b), 42 U.S.C. §7411(b), the Act requires EPA to set standards for states to regulate emissions from existing

sources in that industr y. 42 U.S.C. § 7411(d).] [FN5: In re: Deseret Power Electric Coop., PSD App. No 07-03, Slip Op. (Nov. 13, 2008). The memorandum issued December 18, 2008 by Administrator Johnson entitled "EPA’ Interpretation of Regulations that determine Pollutants Covered by Federal Prevention of Significant Deterioration (PSD) Permit Program" (Johnson PSD memo) is procedurally deficient, and, in any even t, states explicitly on its face that it is not intended to supersede the EAB’s decision in the Deseret case. Johnson memo at 2. Nor, indeed, can it lawfully do so.]

Individual Response: The purpose of the Class VI GS regulat ion is to ensure consistency in permitting underground injection of CO2 at GS operations across the United States and provide requirements to prevent endangerment of USDWs in anticipation of the eventual use of GS to reduce CO2 emissions. The requirements apply only to GS injection tech nologies including well construction, operation, monitoring and testing technologies. The Suprem e Court decision under Massachusetts v. EPA and Clean Air Act (CAA) provisions related to New Source Performance Standards (NSPS) and Best Available Control Technology (BACT) determinations are outside the scope of this Class VI GS rulemaking.

4The Class VI GS rulemaking is promulgated und er Safe Drinking Water Act authority and does not relate to any endangerment and cause or contribute findings under the Clean Air Act. The Class VI GS requirements do not depend upon, and are unaffected by, Clean Air Act endangerment and cause or contribute findings. More information on EPA's Endangerment and Cause or Contribute Findings for Greenhouse Ga ses under Section 202(a) of the Clean Air Act can be found at http://www.epa.gov/climatechange/endangerment.html.

In a separate rulemaking under authority of th e Clean Air Act, EPA is amending the Greenhouse Gas Reporting Program at 40 CFR Part 98 to ad d reporting requirements for CO2 injection and geologic sequestration. The greenhouse gas report ing requirements build on the requirements

outlined in the Class VI GS rule with the a dditional goals of verifying the amount of CO2 sequestered and collecting data on any CO2 emi ssions to the surface fr om GS facilities.

Letter ID: 0250 Comment ID: 22274 Letter Lines: 169 to 192

Comment Code: 1280 1.1.2.1 General comments on climate change/ global warming

Comment: In comments on the Agency’s recent adva nced notice of proposed rulemaking on using the Clean Air Act to combat climat e change, a coalition of environmental NGOs, including some members of our Envi ronmental NGO Group, pointed out that for the U.S. to achieve its necessary c limate goals, controlling CO2 emissions from new and existing sources of CO2 is required. That necessitates reductions from all sectors, including radical shifts to zero-emitting technologies and corrective action on existing sources. These reductions wi ll require targeted measures and policies, which include air regulations that would set CO2 emissions standards implicating the capture and sequestration of CO2. Setting an NSPS or a BACT standard based on CO2 cap ture technology necessa rily creates a need for complementary requirements to assure that the captured CO2 is effectively isolated from the atmosphere. At this time, such an outcome requires injecting CO2 underground for permanent sequestration in either hydrocarbon reservoirs or deep saline formations. Such permanent sequestration clearly meets the definition of underground injection, re gulated by the UIC program of the Safe Drinking Water Ac t ("SDWA").[FN6]

[FN6: 6 42 U.S.C. §300h, et seq. Geologic se questration of CO2 cl early meets the definition of underground injection f ound at 42 U.S.C. §300h(d)(1), "the subsurface emplacement of fluids by well injection." Carbon dioxide, whether injected in a supercritical state, or as a gas, meets the definition of a fluid included in the existing regulations unde r the SDWA: those rules state that a "fluid" is "any material or substance which flows or moves whether in a semisolid, liquid, sludge, gas or othe r form or state." 40 CFR § 144.3.]

Individual Response: EPA agrees that GS is one technology in a portfolio of options, including energy conservation, efficiency improvements, a nd the use of alternative fuels and renewable energy sources, that could be deployed to re duce CO2 emissions. However, the use of and

5investment in these technologies is outside the scope of the Class VI GS rulemaking. The Class VI GS requirements are designed to ensure that , where GS is deployed, projects are permitted, sited, constructed, operated, and closed in a ma nner that protects USDWs from endangerment.

Letter ID: 0250 Comment ID: 22275 Letter Lines: 186 to 192

Comment Code: 1430 1.2.1.2 Support EPA's authority to regulate CO2 injection

Comment: [FN6: 6 42 U.S.C. §300h, et seq. Geologic se questration of CO2 cl early meets the definition of underground injection f ound at 42 U.S.C. §300h(d)(1), "the subsurface emplacement of fluids by well injection." Carbon dioxide, whether injected in a supercritical state, or as a gas, meets the definition of a fluid included in the existing regulations unde r the SDWA: those rules state that a "fluid" is "any material or substance which flows or moves whether in a semisolid, liquid, sludge, gas or othe r form or state." 40 CFR § 144.3.]

Individual Response: EPA agrees that the SDWA provides EP A with the authority to regulate underground injection of CO2 for GS (42 U.S.C. 300h et seq.). Injecti on wells are regulated under SDWA’s UIC Program. Under the SDWA, the in jection of any "fluid " is subject to the requirements of the UIC program. "Fluid" is de fined under 40 CFR 144.3 as any material or substance which flows or moves, whether in a semisolid, liquid, sludge, gas or other form or state, and includes liquids, gases, and semisolids (i.e., slurries) injected into the subsurface.

Letter ID: 0250 Comment ID: 22276 Letter Lines: 194 to 197

Comment Code: 1000 1. General and Administrative Comments

Comment: We therefore are pleased to submit these comments on EPA’s proposed rules concerning "Federal Requirements Under the Underground Inject ion Control (UIC) Program for Carbon Dioxide (CO2) Geologic Sequestration (GS) Wells, 73 Fed. Reg.43492 (July 28, 2008).

Individual Response: EPA acknowledges the comment. Pleas e see the remainder of EPA's responses to this comment for further deta ils. For additional information on EPA's final regulatory approach, please see the final rule and preamble as well as the rulemaking docket.

Letter ID: 0250 Comment ID: 22277 Letter Lines: 199 to 248

Comment Code: 1430 1.2.1.2 Support EPA's authority to regulate CO2 injection

Comment: B. The Safe Drinking Water Act Authorizes EPA to Create a Preventive, Forward Looking, and Adaptive Program Sp ecific to CO2 GS Permitting

Under the SDWA, EPA’s authority to prot ect USDWs is clearly defined, broadly

6scoped, and forward looking. [FN7] Section 1421 requires the Administrator to publish rules for state implemented undergr ound injection programs that "prevent underground injection which endangers drinki ng water sources" as that phrase is further defined by the stat ute. [FN8] Such programs, at a minimum, must "prohibit any underground in jection ... which is not authorized by a permit," [FN9] and such permit programs must requir e a showing to the sa tisfaction of the state that the underground injection will not endanger drinking water sources. ..." [FN10] Underground injection "endangers drinking water sour ces if such injection may result in the presence in underground wa ter which supplies or can reasonably be expected to supply any public water sy stem of any contaminant, and if the presence of such contaminant may result in such system’s not complying with any national primary drinking water regulation or may otherwise adversely affect the health of persons. [FN11] And "contam inant" is defined as "any physical, chemical, biological, or radiological s ubstance or matter in water." [FN12] Underground injection furthermore is prohi bited without a permit, and to receive a permit the applicant must demonstrat e that endangerment "will not" occur. [FN13] This preventive, broadly scoped language demonstrates that Congress intended that all underground injection be regulated under the UIC program. [FN14]

[FN7: While our Environmental NGO Group agr ees that EPA’s primary authority for the promulgation of this rule is found in the Safe Drinking Wate r Act, we also point out above that the Clean Air Act authorizes contro ls on CO2 emissions that necessarily implicate and necessi tate this UIC approach, a nd so also can be said to provide authority for Cl ass VI rules. EPA must exercise its Clean Air Act authority to regulate CO2 for the purposes of preventing its release to the atmosphere. Additionally, and more gene rally, EPA could also promulgate verification and accounting pr otocols for CO2 GS, as n eeded, under those Clean

Air Act rules. Such Clean Air Act rule s may or may not prove adequate for purposes of any future legislatively cr eated trading system. Clearly, however, the UIC rules should not be regarded as sufficient to authorize or certify carbon credits as part of such a system, as they do not provide sufficient proof that CO2 will be permanently sequestered from the atmosphere, nor do they

include additional detail s necessary for verifying and quantifying any atmospheric releases.] [FN8: 42 U.S.C. §§ 300h(a)(1),(b)(1).] [FN9: Id. § 300h(b)(1)(A).] [FN10: Id. § 300h(b)(1)(B).] [FN11: Id. § 300h(d)(2).] [FN12: 42 U.S.C. § 300f(6).] [FN13: 42 U.S.C. § 300h(b)(1)(A), (B).] [FN14: See also NRDC v. EPA, 824 F .2d 1258, 1271 (1st Cir. 1987), holding that Congress intended the phrase "underground injection which endangers drinking

water sources" should have the broadest applicability, and citing and quoting H.R. Rep. No. 1185, 93d Cong., 2d Sess., reprinted in 1974 U.S. Code Cong. & Admin. News at 6484.]

7Individual Response: EPA agrees that the SDWA provide s the EPA with the authority to regulate underground injection of CO2 for GS. ( 42 U.S.C. 300h et seq.). Injection wells are regulated under SDWA’s UIC Program. Under the SD WA, the injection of any "fluid" is subject to the requirements of the UIC program. "Fluid " is defined under 40 CFR 144.3 as any material or substance which flows or moves, whether in a semisolid, liquid, sludge, gas or other form or state, and includes liquids, gases, and semisolids (i.e., slurries) injected into the subsurface.

EPA acknowledges that GS falls within the broade r context of CCS and the need for regulatory clarity to ensure that USDWs are protected from endangerment. In develo ping the final GS rule,

the Office of Water coordinated with other Agency program offices and across federal agencies (e.g., with the Department of Energy; United Stat es Geological Survey; Bureau of Ocean Energy Management, Regulation, and Enforcement, formerly the Minerals Management Service; Bureau of Land Management). The Agency continues to eval uate areas of potential applicability of other Federal environmental statutes including, but not limited to: the Clean Air Act; the Resource Conservation and Recovery Act; the Comprehe nsive Environmental Response, Compensation, and Liability Act; and the Marine Protection, Resear ch and Sanctuaries Act to various aspects of GS and CCS. The Agency will continue to coordina te on GS and CCS related issues to minimize redundancy and maximize efficiencies for owners or operators. For additional information, please see the discussion entitle d "How Does This Rulemaking Relate to Other Federal

Authorities and GS and CCS Activities?" in the preamble to the final GS rule.

EPA acknowledges that carbon crediting and gree nhouse gas accounting are important issues. However, these issues are outside of the UIC Program's authority under the Safe Drinking Water Act and outside the scope of th is rulemaking. The UIC requirement s are designed to ensure that where GS is employed, it is done in a manner that protects USDWs from endangerment. All of the requirements of the GS rule are for the purpose of protecting USDWs from endangerment, consistent with the UIC Progr am's authority under SDWA.

Letter ID: 0250 Comment ID: 22279 Letter Lines: 250 to 264

Comment Code: 2020 1.5.1 Support Class VI designation

Comment: The statute provides additional direction to EPA in developing its rules - the rules must "permit or provide for co nsideration of varying geologic, hydrological, or historical conditions, in different St ates and in different areas within a State," [FN15] and they ar e not to "interfere with or impede" underground injections for the purposes of "the secondary or te rtiary recovery of oil or natural gas, unless such requir ements are essential to assure that underground sources of drinking water will not be endangered by such injection." [FN16] While EPA is not free to exempt a particular class of injection entirely from rulemaking, the Agency is authori zed to tailor the UIC rules to the specific geologic conditions and also to particular injecti on activities. The statute clearly authorizes EPA to create a new class or classes of UIC wells for the purpose of CO2 sequestration.

8[FN15: 42 U.S.C. § 300h(b)(3)(A).] [FN16: Id. § 300h(b)(2)(B).]

Individual Response: EPA agrees that the final GS rule making, which creates a new class of well, is absolutely within the Agency’s auth ority provided under the SDWA. EPA agrees that tailored requirements for Class VI wells are nece ssary to address the unique nature of injecting large volumes of CO2 and to ensu re that USDWs are protected from endangerment. The GS rule contains tailored requirements for the perm itting, geologic site ch aracterization, AoR and corrective action, well construc tion, operation, mechanical integr ity testing, monitoring, well plugging, post-injection site care, an d site closure of GS wells that directly address issues unique to the nature of large-scale CO2 injection for GS.

Letter ID: 0250 Comment ID: 22280 Letter Lines: 266 to 284

Comment Code: 2400 1.8 Comments on EPA's adaptive rulemaking process

Comment: This precautionary, forward looking statutory purpose a nd structure authorizes EPA also to take an adaptive approach, bot h in rulemaking and in defining permit terms, specifically to direct states to be adaptive in mon itoring, tracking, and updating permits, in order to reflect less ons learned from experience and from monitoring reports. The statute also authorizes EPA to take an adaptive approach to the rules themselves. Section 1421( a)(1) states that "any regulation [governing underground injecti on activities] may be ame nded from time to time." [FN17] Whereas, as is the case with EPA’s proposed Cla ss VI rules, regulations are established to govern a system on a scale of deployment that has not yet been demonstrated [FN18], the preventive a nd precautionary nature of the UIC statute demands a periodic review, assessment, and update of the rule. EPA should, in its final rule, declare its intention to u ndertake such a process. Moreover, our Environmental NGO Group recommends that EPA commit itself to issuing a Notice of Proposed Rulemaking by no later than an id entified date, perhaps in 2020, which would formally initiate this process.

[FN17: 42 U.S.C. § 300h(a)(1).] [FN18: Although the practice of injection/ GS has been demonstrated at the individual project scale.]

Individual Response: EPA agrees that an adaptive approach to the UIC GS rulemaking is appropriate. However, the Agency does not feel that in order to use such as approach they need to commit to a date for a proposed rulemaking. The Agency plans to use an adaptive approach to ensure that USDWs are protecte d from endangerment and meet the potentially fast pace of GS deployment. EPA believes that an adaptive a pproach will allow regulatory development to proceed in time to meet the current and future demand for Cl ass VI permits while recognizing the need to: continue to gather data from pilot projects and other research as it becomes available; and to enhance understanding of th e technical and administ rative aspects of GS deployment, operation, and technology developments.

9EPA plans, every six years, to collect and review data on GS projects to determine whether the appropriate amount and types of information a nd appropriate documentation are being collected,

and to determine if modifications to the re quirements are appropr iate or necessary.

Letter ID: 0250 Comment ID: 22281 Letter Lines: 286 to 320

Comment Code: 1420 1.2.1.1 Support the GS rulemaking

Comment: C. The Proposed Rule Has Many Positive Features

Before offering comments on the proposal it self, we want to praise and lend our support to EPA for incorporating, or in so me cases intending to incorporate, a

number of features of the rule that we regard not so lely as desirable, but

essential. These include:

• specific requirements for a comprehensiv e characterization before deeming a sequestration site as appr opriate for injection; • monitoring requirements fo r tracking the behavior and location of CO2 in the subsurface, validating its c onfinement, or detecting unw anted behavior early to allow for corrective action; • the need to compile a monitoring plan, a site care and closure plan and a remedial response plan prior to obtaining a permit; • the requirement to update and report on these plans, incl uding the area of review adjustment process, as monitoring and operational data become available; • a requirement for a continuous feedback loop between monitoring and modeling, whereby one updates the other in order to optimize operations and refine simulations; and

• a criterion for site closure that is no t based on the mere passage of a set number of years, but on th e finding that drinking wate r is not endangered and that the project meets the necessary pe rformance standards (we note, however, that articulation of the performance standa rds that need to be met in order to make such a finding is one of the areas where the rule needs work).

These features are captured to differi ng extents by the proposed rule’s language, and our suggested changes below serve to reinforce these features. Some of these features appropriately go beyond what is currently required under existing well classes in the UIC program. We regard them as necessary for the effective regulation of GS in the Class VI context, and strongly support them. We would therefore label our proposed ch anges as technical modifications, and not radical changes in the rule. Even though these strengthening changes are needed, we urge EPA to maintain the basi c structure of the rule as proposed and thank the drafting working group for produc ing the proposed rule in a short

timeframe.

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

10technology 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 subs urface geologic formations. For additional information, please also see the discussion of EP A’s Final Regulatory Approach in the preamble

to the final GS rule.

Letter ID: 0250 Comment ID: 22282 Letter Lines: 322 to 338

Comment Code: 1200 1.1 General comments about the rulemaking

Comment Code: 2020 1.5.1 Support Class VI designation

Comment: D. General Comments

Timing of promulgation

The proposed rule is based on a risk manage ment approach and is written in a way that should avoid unintended consequences to USDWs. It is important to bear in mind that CO2 injection projects can already be permitted today. While this may be adequate to protect USDWs in certain cases, it is in the interests of the public (and the regulated industry) to have a new injection class, designed from the outset with the partic ular characteristics of GS in mind, as soon as possible. This is necessary in order provi de certainty and adequately safeguard public health and the environment. If the final rule incorporates changes concerning the adaptive nature of the ru le and permits, as our Environmental NGO Group suggests, the Agency, and its state c ounterparts, will be able to deal with such unintended consequences to US DWs through the rule’s performancebased provisions, review and a po ssible reissuance of permits if necessary, and by revising the rule text if appropriate.

Individual Response: EPA agrees that the tailored requirem ents for Class VI wells, pursuant to the final GS rulemaking, are necessary to address the unique nature of inje cting large volumes of

CO2 and to ensure that USDW s are protected from endangerment, and that a new well Class specific to GS is appropriate. The GS rule co ntains tailored requirements for the permitting, geologic site characterization, AoR and corre ctive action, well construction, operation, mechanical integrity testing, monitoring, well plu gging, post-injection site care, and site closure of GS wells that directly addre ss issues unique to the nature of large-scale CO2 injection for GS.

EPA adds that it continues to monitor resear ch being conducted on GS and will use this to inform its adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects to determine whether the approp riate amount and types of information and appropriate documentation are being collected, and to determine if modifications to the requirements are approp riate or necessary.

11Letter ID: 0250 Comment ID: 22283 Letter Lines: 340 to 356

Comment Code: 1200 1.1 General comments about the rulemaking

Comment Code: 1640 1.3.4 CERCLA issues (seeking comment)

Comment Code: 2020 1.5.1 Support Class VI designation

Comment: We consider the Phase III Deployment Phase of the Department of Energy’s (DOE) Regional Partnership Program to be very worthwhile, but we do not consider the completion of this program to be a prerequisite for either commercial implementation of CCS or for the promul gation of a sound and protective rule. The DOE’s program has limited funds avai lable through appropriations, and its demonstration projects will be of limite d scale and duration. In addition, it focuses as much or more on the optimum wa y to apply existing technologies as it

does on fundamental research or even demons trations that partic ular technologies

"work." Our scientific and practical understanding and experience in GS itself,

as well as in related und erground injection activitie s, is sufficient to construct and operate the fi rst large-scale, commercial plants in the U.S., provided they are regulated adequately. In that respect, we do not consider the proposed rule premature, but a very timely and necessary development.

The rule itself, rather than individual permits, should assure that Class VI permits do not allow responsible parties to avoid CERCLA liability on grounds that a release constitutes a "federally permitted release"

Individual Response: EPA agrees that tailored requirements for Class VI wells are necessary to address the unique nature of in jecting large volumes of CO2 a nd to ensure that USDWs are protected from endangerment. The GS rule c ontains tailored requirements for the permitting, geologic site characterization, AoR and corre ctive action, well construction, operation, mechanical integrity testing, monitoring, well plu gging, post-injection site care, and site closure of GS wells that directly addre ss issues unique to the nature of large-scale CO2 injection for GS.

EPA believes, as supported by the rule's admi nistrative record, that sufficient data and experience currently exist to de velop UIC regulations for GS wells. The GS rulemaking builds upon decades of knowledge about safe injection practices. While developing the GS regulation,

EPA has evaluated relevant GS research, including projects conducted by the seven regional carbon sequestration partnerships funded by the U.S. Department of Energy and coordinated through the National Energy Techno logy Laboratory (NETL), and several international projects. Additionally, EPA's Office of Wa ter continues to fund research at the Lawrence Berkeley National Laboratory examining the effects of CO 2 interaction with ground water aquifers and any potential mobilization of trace elements that may occur.

CERCLA exempts from liability, under CERCLA section 107, 42 U.S.C. 9607, certain "federally permitted releases" (FPR) as defined in CERCLA, 42 U.S.C. 9601(10). Therefore, Class VI requirements and permits will need to be carefully structured to ensure that they do not 'authorize' inappropriate releases, and would need to prevent potential releases from the well

12which are outside the scope of the Class VI pe rmit. Furthermore, EPA is promulgating the GS rule under the authority of the SDWA. To the exte nt the commenter is seek ing interpretations of CERCLA and its related provisions, such as the definition of a federally permitted release, such interpretations are beyond the scope of this rulemaking.

The UIC program Director has authority under SDWA §1423 to address potential compliance issues (e.g., potential releases that may endanger USDWs) resulting from injection violations in the unlikely event that a remedi al response is necessary. Although EPA anticipates that the need for emergency or remedial actions at GS sites wi ll be rare, the GS rule requires, at §146.94, that emergency and remedial response plans be deve loped and updated to address such events and that owners or operators demonstr ate that financial resources are set aside to implement the plans if necessary, per §146.85.

Regarding long term liability, once an owner or operator has met all regu latory requirements

under Part 146 for Class VI wells and the Dire ctor has approved site closure pursuant to requirements at §146.93, the owner or operato r 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 or 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. EPA does not have authority to transfer SD WA 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.

EPA recognizes the significant amount of data generated by the DOE partnerships and agrees

that sufficient data have been collected to info rm the final GS rule. EPA has evaluated permits and reviewed operational data and informati on associated with th e seven regional carbon sequestration partnerships funded by the U.S. De partment of Energy and coordinated through the

13National Energy Technology Laboratory. EPA believes that these projects form a solid basis for finalizing the GS requirements, and agrees there is no reason to wait until all phases of the DOE demonstration tests are complete.

Letter ID: 0250 Comment ID: 22284 Letter Lines: 358 to 368

Comment Code: 1640 1.3.4 CERCLA issues (seeking comment)

Comment: EPA notes in the preamble to the propos ed rule (73 Fed. Reg. 43504) that CERCLA exempts from liability certain "federally permitted releases, including releases in compliance with a UIC permit under the Safe Drinking Water Act." EPA further notes that "Class VI requirements and permits will need to be carefully structured to ensure that they do not ‘authorize’ inappropriate hazardous releases." Our Environmental NGO Group st rongly urges EPA to go further and effectively prohibit Class VI permit conditi ons that would make the "federally permitted release" defense available s hould injected fluids or displaced formation fluids enter or endanger USDWs. We suggest that such a prohibition be added to Subpart E - Permit Conditions, or to any other section of the rule that EPA finds appropriate.

Individual Response: CERCLA exempts from liability, un der CERCLA section 107, 42 U.S.C. 9607, certain "federally permitted releases" (FPR ) as defined in CERCLA, 42 U.S.C. 9601(10). Therefore, Class VI requirements and permits will n eed to be carefully structured to ensure that they do not "authorize" inappropria te releases, and would need to prevent potential releases from the well which are outside the scope of the Cla ss VI permit. Furthermore, EPA is promulgating

the GS rule under the authorit y of the SDWA. To the extent the commenter is seeking interpretations of CERCLA and its related provi sions, such as the definition of a federally permitted release, such interpretations are beyond the scope of this rulemaking.

The UIC program Director has authority under SDWA §1423 to address potential compliance issues (e.g., potential releases that may endanger USDWs) resulting from injection violations in the unlikely event that a remedi al response is necessary. Although EPA anticipates that the need for emergency or remedial actions at GS sites wi ll be rare, the GS rule requires, at §146.94, that emergency and remedial response plans be deve loped and updated to address such events and that owners or operators demonstr ate that financial resources are set aside to implement the plans if necessary, per §146.85.

Regarding long term liability, once an owner or operator has met all regu latory requirements

under Part 146 for Class VI wells and the Dire ctor has approved site closure pursuant to requirements at §146.93, the owner or operato r 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

14operator 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 or 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. EPA does not have authority to transfer SD WA 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.

EPA recognizes the significant amount of data generated by the DOE partnerships and agrees

that sufficient data have been collected to info rm the final GS rule. EPA has evaluated permits and reviewed operational data and informati on associated with th e seven regional carbon sequestration partnerships funded by the U.S. De partment of Energy and coordinated through the National Energy Technology Laboratory. EPA believes that these projects form a solid basis for finalizing the GS requirements, and agrees there is no reason to wait until all phases of the DOE demonstration tests are complete.

Letter ID: 0250 Comment ID: 22285 Letter Lines: 370 to 391

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

Comment Code: 5800 2.13 Comments on emergency and re medial response (40 CFR 146.94)

Comment: The rule should incorporate a "non-in terference principle" to keep one sequestration project from interfering with the effectiveness of another

As EPA notes in the preamble (page 43506), "it is ... possible that multiple owners or operators will be injecting CO2 into formations that are hydraulically connected and thus the elevated pressure zones may intersect or interfere with each other." Our Environmental NGO Group agrees that this is a genuine possibility at this stage in GS implem entation. Until comprehensive approaches to basin-scale management are developed, we urge the adoption of the following addition to §146.94:

"(e) If an owner or operator obtains evid ence that a pressure front associated with one geologic sequestration project in tersects or threatens to intersect a

15pressure front associated with any ot her project, the ow ner or operator obtaining such evidence must notify th e Director and the other owner or operator. If the Director determines that the pressure front associated with one project interferes or threatens to interfer e with the ability of a project that began operations at an earlier date to sequester the earlie r project’s total anticipated volume of the carbon dioxide stream as determined under §146.83(a), the Director may require the owner or operator of the project that began operations at a later date to modify op erations as necessary to avoid such

interference."

Individual Response: EPA agrees with the commenter that there are a variety of factors that may affect the need for emergency and remedial response at GS sites. EPA believes that the GS Rule adequately protects USDWs from being endangered by multiple wells. EPA has decided not to adopt the commenter’s edit. However, the Agency believes that a site-specific emergency and remedial response plan that is informed by required site characte rization data (per §146.82), modeling for AoR evaluations and reevaluati ons (per §146.84), and monitoring data (per §146.90) will appropriately address commenter concerns regarding the potential impacts of multiple GS projects. EPA has added a requirement at §146.94(d) that owners or operators must review their emergency and remedial response pl an within one year of an AoR reevaluation required under §146.84 or following significant changes to the facility. Subs equently, the owners or operators must submit an amended plan or demonstrate to the Director that no amendment to the plan is needed based on the AoR reevaluation or any significant changes made to the facility.

EPA also encourages owners or operators and permitting authorities to communicate planned GS activities during initial permitting activities to maximize coordination and minimize pressure interference. If a permit applicant (or the permitting authority) is aware of pending GS projects near a proposed well, the AoR delineation perf ormed pursuant to §146.84 should account for the impacts of multiple owners and operators injecting within a single basin. EPA expects that, where multiple operators are involved, the Director will not approve modeling that does not account for changes that may result from all injection operations.

EPA expects that changes within the AoR, such as the addition of new wells or projects that could potentially interfere with a GS project, will be identified as part of the AoR reevaluations required at §146.84(e) and would need to be a ddressed in a revised emergency and remedial response plan. EPA is developing guidance on th e development and implementation of project plans for GS sites, including emerge ncy and remedial response plans.

Letter ID: 0250 Comment ID: 22286 Letter Lines: 393 to 402

Comment Code: 1200 1.1 General comments about the rulemaking

Comment: Process for permit review by experts

We recommend that EPA consider establis hing a process to collect input from experts to help inform EPA and states on evolving GS technol ogy and appropriate policy and regulatory responses. Partic ipants in the process should be

16independent, non-partisan, unbiased experts in the field, We recommend that the participants not be convened under the Fe deral Advisory Committee Act. Their opinions would be non-binding. Obtaining su ch input would help regulators improve their permitting decisions and would be complementary to the objectives of increased funding and resources for the UIC Program, outlined below.

Individual Response: The final rule is based on the most recent GS-related data, information,

and scientific research available. EPA believes that sufficient data have been collected to inform the final GS rule. Nevertheless, EPA anticipates th at future experimental and full-scale projects will continue to inform the technology, and is therefore using an adaptive rulemaking approach. EPA plans, every six years, to collect and review data on GS projects to determine whether the appropriate amount and types of information a nd appropriate documentation are being collected,

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

Please see the remainder of EPA' s responses to this comment le tter for further details. For

additional information on EPA's fi nal regulatory approach, includi ng the discussion of the public participation requirements, please see the final rule and preamble as well as the rulemaking

docket.

Letter ID: 0250 Comment ID: 22287 Letter Lines: 404 to 433

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

Comment: Funding and resources for the UIC Program

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 well as an efficient processing time, they will require additional trained staff and other resources.

Significant additional resources will need to be made available to hire new permitting staff and field inspectors. Thos e new staff, along with existing UIC staff, must be trained in subjects th at will enable them to make prudent permitting, management, and oversight decision s. EPA and states will need to be adequately prepared to review applications and make permitting decisions. Failure to provide sufficient resources will likely create permitting backlogs or result in suboptimal permits being issued.

The Ground Water Protection Council (GWPC) estimated in 2004 that an annual

17funding increase to $56 million would be need ed just to meet the needs of the existing UIC program at the state level ev en without the addition of GS project permitting.[FN19] GWPC has fu rther 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.

[FN19: 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.

Letter ID: 0250 Comment ID: 22288 Letter Lines: 435 to 453

Comment Code: 5520 2.10.1 Appropriateness of existing p ublic participation requirements (Part 25 and Part 124) for GS (seeking comment)

Comment: Public Water Systems should receive notice of permit applications and have the opportunity to participate in the permitting process

EPA should adopt the existing requirements for public participation at 40 CFR Part 25 and 40 CFR Part 124 as suggested in the proposal. UIC Program Directors should also incorporate modern communi cation technologies (cable television, various internet tools) to increase the likelihood of ef fective public understanding and involvement. Engaging the public as soon as candidate

locations are identified will also increa se the effectiveness of the effort. Given the focus of the rule on preventing harm to USDWs, UIC Program Directors should work with primacy agencies and departments with responsibility for implementing other aspects of SDWA to id entify and notify Public Water Systems (PWSs) with a potential interest in the project. PWSs are an important stakeholder in the projects and should be the focus of targeted outreach at every stage of the permitting process. PWS representatives should be invited to serve on any Advisory Groups or other bodi es set up during the lifetime of the project. We suggest that in Guidance to accompany this rulemaking, EPA urge owners and operators to establish on-going relationships with potentially impacted PWSs.

Individual Response: EPA agrees and has adopted th e existing public participation requirements at 40 CFR Part 25 and 40 CFR Pa rt 124. EPA encourages but does not require

18operators and permitting agencies to begin involving the public by providing information as early in the GS project development process as possible. Furthermore, the Agency recognizes that the initial phases of site evaluation and site selection may begin in advance of permit application submission. The public may become aw are of these activitie s and begin to have questions or concerns about th e pending project. For this reas on, outreach and education—which are outside of, but complementary to, the public notification process—can help clarify project details and avoid public misperceptions about the natu re and safety of GS projects. This may also benefit the owner or operator by improving local accep tance of the site. The public will also have the opportunity to submit written comments and, in many cases, attend hearings if requested on proposed GS projects during formal public comme nt periods. Permitting authorities must follow the public participation requirements for UIC permits specified in 40 CFR Part 124.10 which generally requires that the public notice include information about where interested parties can obtain copies of the draft permit and applicati on. In addition, the existi ng public participation requirements for UIC permits at 40 CFR 124.10(c)(1 )(x)(A) require notificat ion "to any unit of local government having jurisdiction over the area where the facility is proposed to be located."

In addition, the final rule now requi res notification of the director of the state public water supply supervision program (drinking wate r program) of the availability of the draft Class VI permit. See 40 CFR §124.10(c)(1)(xi). EPA anticipates that the Director of the drinking water program will inform public water systems located withinthe proposed area of review about the permit application.

EPA agrees with commenters that the use of new forms of information technology can improve public participation and understand ing of GS projects and the asso ciated injection technologies involved. EPA does not require the use of any ne w information technologies to inform the public, but encourages GS project operators and pe rmitting authorities to use the Internet as well

as both new and established tool s to explain and post informati on on the latest developments. This information may include schedules for he arings, briefings, and other opportunities for involvement. EPA plans to conduct outreach on the GS rule, and provides GS related information on its website at http://water.epa .gov/type/groundwater/uic/ wells_sequestration.cfm. EPA currently uses social networking applica tions for important information (e.g., Facebook and Twitter), and will encourage GS operators and pe rmitting authorities to use similar technologies to keep the public inform ed of GS projects.

Letter ID: 0250 Comment ID: 22289 Letter Lines: 455 to 466

Comment Code: 4110 2.4.1.1 Injection pressure limitations

Comment: Pressure limits

We believe that the pressure manage ment provisions in §146.88(a) require

modification. The members of our Envi ronmental NGO Group have not reached agreement on the exact language for the suggested changes and are either submitting individual comments on this issu e or are submitting comments jointly with other groups. We do agree, however, th at injection pressure limits must be established after adequately considering the risks of both te nsile failure and

19shear failure in the confining zone. We al so agree that limits must be designed to avoid causing otherwise non-transmissive faults to become transmissive, in addition to addressing the more traditiona l concern of avoidi ng the initiation or propagation of fractures.

Individual Response: EPA notes that because determination of the injection pressure limit is based on the fracture pressure of the injection zo ne, the limit is site-sp ecific and not arbitrary. EPA emphasizes that injection pressure limits ar e important to protect against fracturing of the confining zone, and that the requ irement at §146.88(a) that the pressure in th e injection zone not exceed 90 percent of the fracture pressure provides a margin of safety in the well operation and protects USDWs from endangerment. If the Dire ctor determines, based on a review of the information collected as part of site characterization, th at a lower injection pr essure limitation is appropriate, the Director has the authority to set a lower limit in the operating 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: 0250 Comment ID: 22290 Letter Lines: 468 to 487

Comment Code: 5220 2.8.2.1 Post-injection monitoring activities

Comment: Site closure standards and framew ork for long-term stewardship

Our Environmental NGO Group did not come to a common set of recommendations on site closure and are either submitting indi vidual comments on this issue or are submitting comments jointly with other gr oups. We do agree, however, that EPA’s

20proposed closure standards in §146.93 need revision. In order to assure that site risks have diminished to the point that it is reasonable to discontinue or significantly reduce monitoring, it is e ssential that the rule require a demonstration of much more than merely ‘p lume stabilization’ and that the nature of what must be demonstrated be prec isely described. In addition, given the desired permanent nature of CO2 seque stration in the subsurface and the importance to the public of ensuring long-te rm oversight of project sites, EPA should use its existing regulatory author ities to establish a framework for long-term stewardship and seek whatever additional authorities may be required for this purpose from Congress. This fr amework should include an entity with responsibility for monitoring and mana ging sites after closure has been authorized. The proposed rule authorizes operators to stop monitoring, but does not provide for the stewardship of sites following closure.. EPA must rectify this omission. It is important that the post-closure framework include financing provisions that are adequate to ensure proper site stewardship in the long-term.

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 individual UIC Dir ectors, in consultation with operators, will be in the best position to determine whether additional post-injection site care is needed. EPA expects this decision to be made based on relevant site data and in consultation with all potentia lly 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 required.

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 perform site closure activities.

Regarding establishing a framewor k for long-term stewardship, EPA clarifies that, once site closure is authorized, the UIC pr ogram has no authority over a site . EPA clarifies that long-term liability for GS sites is outside the scope of this rulemaking after a the CO2 plume has been demonstrated to no longer pose an endangermen t to USDWs and the site has been properly closed pursuant to §146.93. Once an owner or operator has met al l regulatory requirements under

Part 146 for Class VI wells and th e Director has approved site cl osure pursuant to requirements at §146.93, the owner or operator will generally no longer be subject to enforcement for regulatory noncompliance.

Separate from EPA’s authority to enforce regul atory compliance, an owner or operator may be

21subject 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 or 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.

Letter ID: 0250 Comment ID: 22291 Letter Lines: 489 to 502

Comment Code: 5700 2.12 Comments on the proposed durati on of Class VI permits (seeking comment)

Comment: E. Specific Amendments to the Proposed Rule

The rule should authorize Class VI permits for "up to" the operating life of a facility only if the rule is amended to require all aspects of project operations to be modified as appropria te over the course of the project

We support EPA’s proposal in §144.36 to issu e Class VI well permits for a period "up to" the operating life of the facil ity. Still, it is not appropriate to issue these permits for the full opera ting life of the facility without consideration how project performance is evolving. Revisions of the Area of Review, and the various plans outlined in th e proposed rule are to be expected from time to time, and it is possible that some of the needed revisions might be

so material so as to constitute ground for modificati on, revocation or reissuance of the permit.

Individual Response: EPA appreciates the commenter’s concer n and believes that the final rule addresses this concern about adaptability. The final rule main tains the lifetime permit provision and clarifies that the permit extends through the pos t-injection site care peri od (144.36(a)). It also adds a requirement that the Director review each Class VI permit at least once every 5 years to determine whether it should be modified, re voked and reissued, terminated or a minor modification made as provided in §§144.39, 144.40, or 144.41. The Director’s review will be informed by the owners’ or operato rs’ iterative reev aluation of the project. Specifically, the final rule includes a requirement that the AoR be reev aluated at least every five years, and also requires owners or operators to review and update the AoR and corrective action plan, the testing and monitoring plan, and the emergency and reme dial response plan th roughout the life of the project (146.84(e), 146.90(j), and 146.94(d)). Owners or operators must review each plan and identify necessary amendments or demonstrate to the Director that no amendment is needed. In

no case can reviews occur less often than once ev ery five years. The iterative process and subsequent plan reevaluations ensure that time and resources are committed to the most critical aspects of the permit in preven ting endangerment to USDWs.

22EPA believes that the iterative process of develo ping and executing the va rious plans required of GS well operators in the final rule (e.g., for AoR and corrective action, testing and monitoring, injection well plugging, pos t-injection site care, and emergency and remedial response) is tailored to the unique aspects of —and is more appropriate for– GS than establishing a finite permit duration (e.g., ten years as suggested by some commenters).

EPA emphasizes that the Director has the author ity to revise the permit if project operations change or if the director belie ves based on monitoring or operati onal data that the project may endanger USDWs. EPA has also added text to 144.39(a)(5) that permit m odifications would be required if the Director determines that a modification is necessary based on an AoR reevaluation, amendments to any of the project pl ans, or a review of the testing and monitoring results. The Director may also choose to re quire minor permit modifications under 40 CFR 144.41, depending on the extent of the plan amendm ent. All permit modifications, except minor modifications under 40 CFR 144.41, require an oppor tunity for public comment on the portion of the permit that is being reopened pursuant to requirements under 40 CFR Part 124.

The Agency plans to collect and review data on GS projects every six years to determine whether the appropriate amount and types of information and appropriate documentation are being collected, and to determine if modifications to the requirements are appr opriate or necessary.

Letter ID: 0250 Comment ID: 22292 Letter Lines: 504 to 514

Comment Code: 2000 1.5 Need for a New Class of Injection Well

Comment: Class VI is appropriately grouped with Class I Hazardous, Cla ss II and Class III

wells in the modification or revoc ation and reissuance provisions

We believe that EPA in §144.39 has appropria tely listed Class VI alongside other injection classes for which a permit can be revoked and reissued for a specific cause (alterations to the facility, ne w information received and regulatory changes since the permit issued. This is n ecessary in order to ensure that Class VI regulations are adaptive, reflecting experience in GS as it is amassed. We do not support Class VI being listed alongside classes for which the permittee has

control over whether reissue or modificat ion would occur through requesting or agreeing to it.

Individual Response: EPA agrees the Director should have the ability to revoke and reissue a permit for Class VI wells and has retain ed this provision in the final rule.

Letter ID: 0250 Comment ID: 22293 Letter Lines: 516 to 535

Comment Code: 1220 1.1.1.1 Terminology and definitions

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

Comment: The definition of "carbon dioxide stream " should not be restricted to CO2

23captured from industrial sources

The definition of "carbon dioxide st ream" in §146.81(b) includes only carbon dioxide "that has been capt ured from an emission sour ce (e.g., a power plant)." Over time, the vast majority of sequest ered CO2 is likely to be captured from such sources, but rules are also needed to govern the sequestration of naturally occurring CO2 produced from geologic forma tions. We suggest that the definition

be revised to read as follows:

[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf, starting on p. 10, to see the original formatting.]

"Carbon dioxide stream means that has been captured from an emission source (e.g., a power plant), carbon dioxide plus incidental associated substances

derived from the source materials OF THE CO2 AND/OR the capture process, and any substances added to the stream to en able or improve the injection process. This subpart does not apply to any ca rbon dioxide stream that meets the

definition of a hazardous wa ste under 40 CFR part 261."

Individual Response: EPA disagrees with the suggested ed it. The final definition of carbon dioxide stream at §146.81(d) remains unchanged and reads as follows: “[C]arbon dioxide that has been captured from an emission source (e.g., a power plant), plus in cidental associated

substances derived from the source materials a nd the capture process, and any substances added to the stream to enable or improve the injecti on process. This subpart does not apply to any

carbon dioxide stream that meets the definiti on of a hazardous waste under 40 CFR part 261.”

Based on its evaluation of all public comments and input on the proposed rule and the NODA and Request for Comment, EPA has made many revisions to the Cla ss VI GS rule. Please see the final rule and preamble for additional information.

Letter ID: 0250 Comment ID: 22294 Letter Lines: 537 to 538

Comment Code: 3200 2.2 Proposed Area of Review and Corrective Action Requirements (40 CFR 146.84)

Comment: Class VI applicants should be required to identify all known wells penetrating formations affected by increased pressure

Individual Response: EPA clarifies that under 146.84(c)(2 )operators mustidentify all penetrations of the confining zone in the AoR for the GS project. This area would encompass both the CO2 plume and areas of increased pressure associated with CO2 in jection, regardless of which is larger.

24Letter ID: 0250 Comment ID: 22295 Letter Lines: 540 to 569

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

Comment Code: 3440 2.2.2.2 Evaluation of wells in the AoR (e.g., types of data to be reviewed)

Comment: In proposed §144.55(a) the rule would require Class I, II (other than existing), III or VI permit applicants to identify the location "of all known wells within the injection well’s area of review which penetrate the injection zone" or, in the case of Class II wells ope rating over the fracture pre ssure of the injection formation, "all known wells within the area of review penetrating formations affected by the increase in pressure".

Since injection in deep saline formations will result in an area of elevated pressure (above the original reservoir pr essure) that will be larger than the CO2 plume and could affect overlying or underlying formations, we believe that the latter requirement for Class II wells operating above the fracture pressure should also apply to Class VI wells. Th is would help prevent the unwanted migration of reservoir fluids from outs ide the injection zone through existing wells in the confining zone, as a result of the pressure increase. We therefore suggest that §144.55(a) be revise d to read as follows:

[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Coverage. Applicants for Class I, II, (other than existing), or III, or VI injection well permits shall identify the location of a ll known wells within the injection well's area of review which pene trate the injection zone. In the case of Class II wells operating over the fr acture pressure of the injection formation, applicants shall identify the location of a ll known wells within the area of review penetrating formations affected by the increase in pressure. Applicants for Class VI SHALL IDENTI FY THE LOCATION OF ALL KNOWN WELLS

WITHIN

THE AREA OF REVIEW PENETRATING THE INJECTION ZONE AND ALL KNOWN

WELLS WHICH

PENETRATE FORMATIONS AFFECTED BY TH E INCREASE IN PRESSURE AND shall perform corrective action as spec ified in Sec. 146.84."

Individual Response: The final rule leaves §144.55 unchange d; i.e., Class VI wells are not addressed in this prov ision. Based on its evalua tion of all public comments and input on the proposed rule and NODA and Request for Commen t, EPA has made many revisions to the GS Rule. See the final rule and preamble for fu rther discussion on EPA's final approach.

25Letter ID: 0250 Comment ID: 22296 Letter Lines: 571 to 614

Comment Code: 2160 1.6.3 Unmineable coal seams

Comment Code: 2200 1.6.4 Other formation types

Comment: The rule should explicitly exclude from Class VI efforts to sequester CO2 in basalts, coal seams, salt caverns and sh ales, which instead should be regulated under Class V Experimental

We believe that EPA has ample basis fo r adopting rules to regulate geologic sequestration in hydrocarbon reservoirs and in deep brine formations. For these types of geologic formations, there is a widespread technical consensus on how to assess and manage risks, what data is needed to characterize sites, how to select sites, how to conduct injection ope rations, how to model the behavior of CO2 in the reservoir, and how to monitor project performance. There is no such consensus, however, regarding sequestrati on in basalts, coal seams, salt caverns and shales. The trapping mechanisms of CO2 and/or the operat ional engineering involved in such operations is significantly different to those in deep saline formations and hydrocarbon reservoirs, and using identical regulatory language would be ill advised. In fact, it is not known at this time whether sequestration (or even injection in some cases) can even be done at scale in

such formations - efforts in these form ations are very much still in the experimental stage. There is no basis at this time for determining whether rules that are appropriate for wells in hyd rocarbon reservoirs and deep saline formations are also appropriate for wells in these other formations. Until there is better understanding of whether an d how sequestration can be safely accomplished in basalts, coal seams, salt caverns and shales, wells in these

formations should be treated as e xperimental wells under Class V.

Projects designed to evaluate injection in coal seams, salt caverns and shales should be permitted under the UIC Class V provisions and subject to the March 2007 Guidance on "Using the Class V Experime ntal Technology Well Classification for Pilot GS Projects. [FN20] This Guidance clearly states that Class V is intended only for projects "...designed to evaluate the technical issues associated with CO2 injection" [FN21]. The Director should review all Class V GS permit applications to insure that they meet the definition of Pilot Project in CFR 146.3: "... a technology which has not pr oven feasible under the conditions in which it is being tested." The purpose of such pilot projects should be to gather and share information which will l ead to a clearer understanding of the feasibility of such projects on a commercial scale.

[FN20: UICPG#83] [FN21: Id. at p. 1]

In order to implement our suggestion re garding these formations, we recommend revising sections 144.6(f), 144.80(f), 146.5(f) and the definition of

26sequestration in §146.81 accordingly. We suggest retaining the provision in proposed §144.15 that the construction, opera tion or maintenance of any nonexperimental Class V geologic se questration well is prohibited.

Individual Response: EPA acknowledges that site-suitability for GS is dependent on a number of factors and that many formation types may be suitable for GS. The final GS rule does not preclude injection into any forma tion type provided owners or ope rators can demonstrate that GS can be performed in a manner that protect s USDWs from endangerment. The Agency acknowledges that GS into basa lts, coal seams, salt domes, shales, limestone formations, and fractured karst will likely have limited applicati on, or that owners or operators seeking Class VI permits for injection into these formations may not be able to meet the final GS requirements or demonstrate protection of USDWs.

EPA acknowledges that there may be risks associat ed with GS, particularly regarding GS into basalts, which have been the subject of limited e xperimental projects in the past. EPA anticipates that in the short-term, GS into basalts, coal seams, salt domes, shales, limestone formations, and

fractured karst will continue to be experimental in nature (i.e., if they are to test GS technologies and collect data), and will likely be permitted as Class V experimental technology wells and be subject to UIC Program Guidance #83. EPA will continue to review data on early GS projects, including those in such formations, to determ ine whether the appropria te amount and types of information and documentation are required and bei ng collected. EPA plans, every six years, to collect and review data on GS projects to dete rmine whether the appropriate amount and types of information and appropriate documentation are being collected, and to determine if modifications to the requirements are appropriate or necessary.

Letter ID: 0250 Comment ID: 22297 Letter Lines: 616 to 618

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

USDW

Comment: The rule should not prohib it in a blanket fashion GS sites located above the lowermost USDW, but should permit such si tes only under certain conditions that are not applicable to sites below the lowermost 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 inject ion into non-USDW formations above and/or between USDWs. Additionally, the final GS rule doe s not categorically preclude or prohibit injection into any type

of formation.

EPA believes that these requirements will ensure USDW protection while providing flexibility to UIC program Directors and owne rs or operators who undertak e CO2 injection for GS. The Agency believes this approach: 1) responds to co ncerns about local and re gional geologic storage capacity limitations imposed by th e proposed injection depth require ments; 2) allows for a more

27site-specific assessment of injection depth for GS projects; 3) accommodates injection into different formation types; 4) a llows for injection of CO2 for GS into non-USDWs above and/or between USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aqui fer exemptions for GS. Finally, EPA’s approach to addressing injection depth va riability through a waiver process responds to concerns about future drinking wa ter resource availability and the need to ensure that high quality water remains available in sufficient qua ntities to supply drinking water needs. For additional information on the waiver approach, pleas e see the final rule and preamble, as well as EPA's responses to comments on the Notice of Data Availability and Request for Comment.

Letter ID: 0250 Comment ID: 22298 Letter Lines: 620 to 638

Comment Code: 4410 2.4.4.3.1 Comments in favor of allowing injection above/between

USDWs in certain circumstances

Comment: We believe that GS sites located above lowermost USDWs may or may not present more types of risk than sites located be low lowermost USDWs, but that in any event the consequences of leakage from site s above USDWs are likely to be more significant in the event that leakage occu rs. At the same time, we recognize that there many potentially excellent seque stration sites above USDWs and that in some areas these may be the only sites available. We believe the rule should

authorize GS sites above lowermost USDWs only if such sites meet requirements that go beyond what is mandatory for ot her sites. The following additional

conditions would need to be satisfied:

• confirmation that there is a confining zone underlying the entire base of the injection zone; • mandatory monitoring for changes in groundwater chemistry above the upper confining zone and below the lower confining zone; and • prior to permit issuance, and as a cond ition of permit issuance, completion of regional hydrogeologic studies that are conducted with sufficient accuracy to simulate regional hydrologic flows and demonstrate that USDWs would not be endangered if injected or formation fluids were to move beyond either the higher or the lower confining zone.

Individual Response: EPA agrees that there are limited circ umstances where injection above the lowermost USDW can be performed in a manner that protects USDWs from endangerment, as long as appropriate protections are in place. Th e final GS rule at §146.95 establishes a process by which owners or operators can seek a waiver of the Class VI injection depth requirements for injection into non-USDW formations above and/or be tween USDWs.

It establishes requirements specifying information that owners or operators must submit, and Directors must consider (inc luding the presence of confini ng zones above and below the injection zone and detailed hydr ologic evaluation of the proposed site), in consultation with PWSS Directors. Owners or operators of Class VI wells granted a waiver of the injection depth requirements are subject to additional requirements (e.g., ground water monitoring above and

28below the injection zone) to ensure USDW protection above and below the injection zone.

EPA believes that these requirements will ensure USDW protection while providing flexibility to UIC program Directors and owne rs or operators who undertak e CO2 injection for GS. The Agency believes this approach: 1) responds to co ncerns about local and re gional geologic storage capacity limitations imposed by th e proposed injection depth require ments; 2) allows for a more site-specific assessment of injection depth for GS projects; 3) accommodates injection into different formation types; 4) a llows for injection of CO2 for GS into non-USDWs above and/or between USDWs when appropriate and where it can be demonstrated that USDWs will be protected; and 5) responds to concerns about the use of aqui fer exemptions for GS. Finally, EPA’s approach to addressing injection depth va riability through a waiver process responds to concerns about future drinking wa ter resource availability and the need to ensure that high quality water remains available in sufficient qua ntities to supply drinking water needs. For additional information on the waiver approach, pleas e see the final rule and preamble, as well as EPA's responses to comments on the Notice of Data Availability and Request for Comment.

Letter ID: 0250 Comment ID: 22299 Letter Lines: 640 to 664

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

Comment Code: 5800 2.13 Comments on emergency and re medial response (40 CFR 146.94)

Comment: Emergency and remedial response, incl uding response to pot ential problems relating to geologic features, is a nece ssary complement to corrective action

and should remain in the rule. While wells are the most likely conduits for fluid movement into USDWs, the definition of corrective action and the relevant provisions in §146.84 do not take into account the potential for geologic features, such as faults, spill points or fractures, to act as conduits for CO2 or other fluid migration, and hence breach of confinement. Actions to mitigate or remediate a potential breach of conf inement, or a situation which might eventually lead to a breach of confinem ent, should not be limited to corrective action on wells. We therefore strongly support EPA’s inclusion of the Emergency and remedial response section. We propose two minor changes - change §146.94(b) (4) to read:

[In the paragraphs below the text in all CA PS denotes added text. See also EPA-HQ-OW-0390- 0250.pdf to see the original formatting.]

"Implement the emergency and remedi al response plan approved by the Director, AND KEEP HIM APPRIZED OF THE IMPLEMENTATION."

and §146.94(d) to read:

"The owner or operator must notify the Di rector and obtain his approval prior to conducting any well workover OR OTHER RE MEDIATION MEASURES NOT LISTED IN

THE

29EMERGENCY AND REMEDIAL RESPONSE PLAN."

Individual Response: The final rule keeps the language in §146.94(b)(4) as proposed. EPA agrees that the Director shoul d be kept apprised of progre ss on the implementation of the emergency and remedial response plan and expects that the plan itself will include provisions on communications with the Director. EPA agrees that an emergency and remedial response plan is an important part of assuri ng protection of USDWs from en dangerment at GS sites. The requirements for an emergency and remedial resp onse plan at §146.94(a) are designed to ensure that owners or operators, as part of their permit applic ations, comprehensively plan what actions would be necessary in the unlikely event of an emergency. The plan will ensure that operators

know what entities and individuals must be not ified and what actions must be taken to expeditiously mitigate any emergency situations. EPA is developing guidance on the development and implementation of emergency and remedial response plans for GS sites.

Since proposal, EPA has modified the final regu latory language at §146.94( d) to clarify what

constitutes a workover to address a well failur e (which invokes remedi al actions) and what constitutes a maintenance-type workover. For ma intenance-type workovers (i.e., those that are scheduled in advance), the owner or operator must notify and gain approval from the Director prior to beginning the workover. In the final GS regulation, EPA has moved this requirement to the reporting requirements at §146. 91(d) to clarify its intent.

Regarding concerns that notifica tion could delay responses, EPA cl arifies that the GS rule, at §146.94(b), describes procedures owners or opera tors must take in emergency situations. Specifically, upon determining that there is a problem with the we ll that may endanger a USDW, the owner or operator must firs t cease injection, then take all steps reasonably necessary to identify and characterize any release, notif y the Director, and implement the approved emergency and remedial response plan, which ma y include a well workover. EPA believes that ceasing injection (which the ow ner or operator would do immediately and before notifying the Director) is the immediate action necessary to pr event or mitigate endangerment of USDWs as required under the SDWA.

Letter ID: 0250 Comment ID: 22300 Letter Lines: 666 to 683

Comment Code: 1220 1.1.1.1 Terminology and definitions

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

Comment: The definition of "confining zone" should not be limited to formations overlying the injection zone, and should focus on limiting movement through the confining zone rather than out the injection zone

The proposed definition of confining z one in §146.81(d) requires that the

formation act as "a barrier" to flui d movement, which may be unnecessarily

strict. The definition also fails to rec ognize that it is movement through and beyond the confining zone that needs to be limited. We suggest instead that the definition of "confining zone" read as follows:

30[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Confining zone means a geologic formati on, group of formations, or part of a formation stratigraphically o verlying the injection zone that acts as a barrier to limit fluid movement beyond THIS FORMATION, GROUP OF FORMATIONS, OR

PART OF A FORMATION."

Individual Response: EPA disagrees with the suggested edit. However, the Agency has

modified the final definition of confining zone at §146.81(d) to read as follows: “[A] geologic formation, group of formations, or part of a fo rmation stratigraphically overlying the injection zone that acts as barrier to fluid movement. For Class VI wells operating under an injection depth waiver, confining zone means a geologic formation, group of formations, or part of a formation stratigraphically overlying and underlying the injection zone.”

Based on its evaluation of all public comments and input on the proposed rule and the NODA and Request for Comment, EPA has made many revisions to the Cla ss VI GS rule. Please see the final rule and preamble for additional information.

Letter ID: 0250 Comment ID: 22301 Letter Lines: 685 to 726

Comment Code: 1220 1.1.1.1 Terminology and definitions

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

Comment: The second sentence of the definition of ‘geologic sequestration project" should be amended to refer more generally to form ation fluids and be transferred to the

definition of "area of review"

We suggest the following amendment to §146.81(d) in order to be more inclusive on the types of fluid that could be displaced:

[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"[...] It includes the subsurface three-di mensional extent of the carbon dioxide plume, associated pressure front, and displaced brine FORMATION FLUIDS, as

well as the surface area above that delineated region.

We also suggest that this second se ntence of the definition of geologic sequestration project be transferred to the definition of area of review as recommended above. The language provided above reflects the change from "brine"

to "formation fluids."

Moreover, we suggest that the present re striction of Class VI to formations

31below the lowermost USDW is more appropria tely addressed elsewhere. Accordingly, we recommend that geologic sequestrati on project be defined as follows:

[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Geologic sequestration project means an in jection well or wells used to emplace

a carbon dioxide stream beneath the lowermost formatio n containing a USDW INTO

AN INJECTION ZONE FOR GEOLOGI C SEQUESTRATION. It includes the subsurface three

dimensional extent of the carbon dioxide plume, associated pressure front, and displaced brine, as well as the surface area above that delineated re gion."

The term "pressure front" should be replaced with the more accurate term "area of elevated pressure " throughout the rule

The term "pressure front" in 146.81(d) is like ly to be scientifi cally inaccurate as it implies a front, or discontinuity in pressure, whereas in reality there will be a continuous pressure gradient in the formation in most cases. We suggest globally replacing "pressure front " with "area of elevated pressure" throughout the rule.

Individual Response: EPA disagrees with the suggested edit. However, the Agency has modified the definition of geologic sequestrati on project at §146.81(d) to read as follows: “Geologic sequestration project means an in jection well or wells used to emplace a carbon

dioxide stream beneath the lowermost formation containing a USDW; or, wells used for geologic sequestration of carbon dioxide that have been granted a wa iver of the injection depth requirements pursuant to requirements at §146.95; or , wells used for geologic sequestration of carbon dioxide that have received an aquifer exemption expansion. It includes the subsurface

three-dimensional extent of the carbon dioxide plume, associated pressure front, and displaced brine, as well as the surface area above that delineated region.”

The final definition of pressure front at §146.81( d) also is unchanged and reads as follows: “[T]he zone of elevated pressure that is cr eated by the injection of carbon dioxide into the subsurface. For the purposes of this subpart, the pressure front of a carbon dioxide plume refers to a zone where there is a pressure differential su fficient to cause the movement of injected fluids

or formation fluids into a USDW.”

Based on its evaluation of all public comments and input on the proposed rule and the NODA and Request for Comment, EPA has made many revisions to the Cla ss VI GS rule. Please see the final rule and preamble for additional information.

Letter ID: 0250 Comment ID: 22302 Letter Lines: 728 to 751 ; 763 to 765

Comment Code: 3420 2.2.2.1 Scope of the inventory pr ocess (e.g., reliance on publicly available information, depth of wells)

32Comment: Additional well identif ication methods that do not rely on the public record should be required in certain provisions

§146.82(b) requires a map to be submitted with the permit that shows wells within the area of review - only informati on of public record is required to be included on this map. §146.82(e) requires a tabulation of all we lls within the area of review which penetrate the injec tion or confining z one(s), including information on the well’s type, constr uction, date drilled, location, depth, record of plugging and/or completion and any additional information that the Director may require.

While we are comfortable with relying on information of public record in subsection (b), we believe that additional diligence is needed when it comes to wells that penetrate the injection or confining zone in subsection (e). Information of public record is often in complete and/or inaccurate. There are numerous orphaned or abandoned wells that are not listed on the public record that could potentially affect the inte grity of the confin ing zone. While generally it is possible to intercept these problems during operations, there are methods available today to identify wells not listed on the public record [FN22], which in many cases could iden tify potentially problematic wells in advance. A requirement to supplement publ ic record information with field

measurements should be included in the rule , and described with a term that is

broader than "tabulation" in order to allow the Director to require other data

formats as needed:

[FN22: NETL , for example, has developed an electromagnetic system that can be used for areal or ground-based identification of wells (casings).]

Individual Response: EPA acknowledges that public record s may not contain data on every artificial penetration in the AoR (or all of th e data on each well that is required for the tabulation), particularly in area s with many older wells. However, EPA notes that the inventory and review process for GS wells required at §146.84(c)(2) is similar to what is required of Class I and Class II injection well ope rators, that the AoR and corrective action process for these well types has been successful for many years.

EPA adds that the Director has the discretion to require the owner or operator to supplement a data records search, including re quiring ground or airborne surveys for wells, if there is reason to believe, based on knowledge of the site or of avai lable data bases, that the incompleteness of available information could compromise USDW protection from endangerment. EPA adds that all corrective action must be pe rformed pursuant to the approved AoR and corrective action plan, which affords the Director the discretion to requi re any additional inform ation needed (including information that is not publically available) to ensure that all necessary corrective action is performed.

33Letter ID: 0250 Comment ID: 22304 Letter Lines: 782 to 798

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

Comment Code: 1616 1.3.1.3 Fluid movement

Comment: The term "transmissive fault or fracture" should be clarified

The proposed rule in §146.83(a )(2) requires a confining zone (s) that is free of transmissive faults or fractures, while §146.81 defines this term as "A fault or fracture that has sufficient permeability and vertical extent to allow fluids to move between formations". We sugges t the following modification to the definition in §146.81(d) in or der to avoid unduly restric ting movement that is merely between formations (compare our comments above on the definition of "confining zone"):

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Transmissive fault or fracture means a fault or fracture that has sufficient permeability and vertical extent to allow fluids to move between formations

BEYOND A CONFINING ZONE."

Individual Response: EPA has retained the definition in the final rule. While there may be cases, as the commenter suggests, where a transm issive fault may exist but not pose a concern for confinement, i.e., in the context of all other information, EPA believes the definition is accurate. Based on its evaluation of all public comments and input on the proposed rule and NODA and Request for Comment EPA has made ma ny revisions to the GS Rule. See the final rule and the geologic site char acterization discussion in the pr eamble for further discussion on EPA's final approach.

Letter ID: 0250 Comment ID: 22305 Letter Lines: 800 to 823

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

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

Comment: Secondary confining zone

§146.83 allows the Director to require a dditional confining zones, at his

discretion. We do not believe that this will always be necessary - a good primary zone should be su fficient. Where additional hazards justify it, a secondary zone might be desirable. In all cases, we caution against relying on secondary confinement in place of establishing with a greater degree of certainty the suitability of the primary zone. Potential problems are best identified and anticipated early, and the focus should be on site

34characterization to show with confid ence whether the confining zones are adequate. We suggest striking part (b) in §146.83 as it seems redundant. However, the Director must have the disc retion to require a se condary confining

zone if needed. We therefore recomme nd clarifying part (a)(2) to read explicitly:

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"A confining zone, or zones , that is ARE free of transmi ssive faults or

fractures and of sufficient areal extent and integrity to contain the injected carbon dioxide stream and displaced forma tion fluids and allo w injection at proposed maximum pressures and volume s without initiatin g or propagating fractures in the confining zone(s)"

Individual Response: EPA disagrees with the suggested ed it, but agrees that providing the Director discretion will allow consideration of a range of sites for GS, based on site-specific conditions and ensure USDW protection. EPA believes that requiring appropriate site characterization by the owner or operator (und er §146.82) and providing an appropriate degree of flexibility to the Director to evaluate site -specific geologic data will afford the greatest protection of USDWs from endangerment. The Agency believes that in some geologic settings, the presence and identification of additional confining and containment zones above the primary (i.e., lowermost) confining zone can improve US DW protection. These formations could further impede vertical fluid movement, allow for pressu re dissipation, and provi de additional sites for monitoring, mitigation, and remediat ion, while also affording the greatest protection of USDWs from endangerment.

Letter ID: 0250 Comment ID: 22306 Letter Lines: 825 to 831

Comment Code: 1220 1.1.1.1 Terminology and definitions

Comment Code: 3300 2.2.1 Delineating the AoR/M odeling CO2 movement

Comment: The area of review provisions should be revised in several respects

Surprisingly, the definition of "area of review" (AOR) in §146.81(d) fails to mention that elevated pressure a critical aspect of what it means for an area to be "impacted" by injection activity. Our Environmental NGO Group recommends borrowing language from the proposed defi nition of "geologic sequestration project" and reworking the "a rea of review" definition.

Individual Response: Although EPA disagrees with the co mmenter's suggested change, the Agency has carefully considered all comments on the AoR definition at 146.84(a) and modified it to read as follows: The region surrounding th e geologic sequestrati on project where USDWs may be endangered by the injection activity. The area of review is delineated using computational modeling that accounts for the physi cal and chemical propert ies of all phases of

35the injected CO2 stream and is based on av ailable site characte rization, monitoring, and operational data. EPA believes that this definitio n is sufficiently broad and describes both the intent of the computational modeling and the relati onship of the AoR to area s that are subject to

the risks associated with injection.

Letter ID: 0250 Comment ID: 22307 Letter Lines: 833 to 854

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

Comment Code: 3300 2.2.1 Delineating the AoR/M odeling CO2 movement

Comment: An additional concern is that both §146.81 and §146.84(a) state that the AOR is "based on computational modeling". This could imply that the Area of Review could be based solely on computationa l modeling. Instead, the AOR should be based on computational m odeling, monitoring and opera tional data (and kept updated until closure is approved). All refe rences to computational modeling in

relation to the Area of Review in this section, as well as in the definition of Area of Review in §146.81 should be amende d as appropriate to read "based on computational modeling, as well as monito ring and other operational data." We urge that the definition be revised as follows:

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Area of review means the AREA that ma y be impacted by the injection activity. The area of review is based on computati onal modeling, as well as MONITORING AND OTHER OPERATIONAL DATA, that account for the physical and chemical properties of all phases of the injected carbon dioxide stream. IT INCLUDES THE SUBSURFACE THREE-DIMENSIONAL EXTENT, THROUGHOUT THE OPERATING LIFE OF THE FACILITY, OF THE CARBON DIOXIDE STREAM PLUME, AS SOCIATED PRESSURE FRONT, AND

DISPLACED FORMATION FLUIDS, AS WELL AS THE OVERLYING FO RMATIONS AND SURFACE AREA ABOVE

THAT

DELINEATED REGION."

Individual Response: Based on review of all public comments on the AoR definition at 146.84(a), the Agency has modified it to read as follows: "The region surrounding the geologic sequestration project where USDWs may be e ndangered by the injecti on activity. The area of review is delineated using computational mode ling that accounts for the physical and chemical properties of all phases of the injected CO 2 stream and is based on available site characterization, monitoring, and operational da ta." The definition in the proposed rule accounted for the varying physical and chemical properties of the CO2 including free-phase and water-dissolved CO2, as the commenter suggests. The definition in the final ru le will continue to

do so.

36EPA is developing guidance on AoR and corrective act ion at GS Class VI s ites to assist owners or operators and Directors in evaluating requi rements and proposed AoR and corrective action plans under 146.84. The guidance describes EPA's reco mmended approaches for the data to be

considered in an initial AoR delineation, how to apply computat ional modeling to delineate the AoR, performing corrective action at GS sites, and, when appropriate, completing AoR reevaluations. The guidance will be available on EPA's web site, at http://water.epa.gov/type/groundwat er/uic/wells_se questration.cfm.

EPA clarifies that the initial AoR delineation required unde r 146.84(c) is performed prior to injection, and therefore no mon itoring or operational data woul d yet exist. The AoR delineation models will incorporate all avai lable site data and anticipat ed operating procedures (e.g., injection rates and volumes).

The AoR reevaluation process required at 146.84(e) requires owners or oper ators to incorporate monitoring or operational data and make any needed adjustments to corrective action or monitoring at the site. EPA believe s that the iterative process of AoR reevaluation is appropriate to verify that the CO2 plume and pressure fr ont are moving through the subsurface as predicted, verify the accuracy of the delineat ion model (or identify needed ch anges), and refine testing and monitoring activities to ensure that USDWs are protected fro m endangerment and that there would be adequate warning of potential problem s at the site before any endangerment could

occur.

Letter ID: 0250 Comment ID: 22308 Letter Lines: 856 to 874

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

Comment: Even though proposed §146.84(f) requires "reevaluation" of the AOR at a "minimum" fixed frequency of ten year s or "when operational and monitoring conditions warrant" (the "and" should be an "or"), §146.84 runs the risk that revisions will not be made on a timely ba sis. Default periods have a way of becoming the standard way of doing busine ss. We recommend imposing a continual obligation on operators to assess wh ether the AOR should be revised, a requirement for an annual report stati ng whether circumstances during the preceding year warranted a revision, and a requirement that revisions be done when required by the Director as well as when the operator determines that conditions warrant. To accomplish this, it will be useful to break down the concept of "reevaluation" in to two ideas - "assessment" of the need to revise the AOR and the actual process of "rev ision." There are several portions of §146.84 that will need to be changed in or der to incorporate these suggestions. We believe that these suggestions will in centivize honest and tr uthful reporting of data and site performance while av oiding the excessive burden of "reevaluating" or revising the Ar ea of Review if such work is not needed. Moreover, a continuous obligation to assess whether revisions are needed, when coupled with the annual reporting requirement just suggested, will create a clear accountability trail for both operator a nd Director in case of disputes.

37Individual Response: EPA agrees with commenters that reevaluations of the AoR every ten years may not be sufficient, and has changed the minimum frequency for the AoR reevaluation from 10 years to at least every 5 years, as spec ified in §146.84(e). EPA believ es that this revised frequency addresses commenters' concerns that more frequent reevaluations ar e necessary to

address the inherent uncertai nties in modeling CO2 movement , the emerging nature of GS technology, risk-based targeting of monitoring activities, and the unique nature of CO2 GS. To the comment that a "minimum frequency" tends to become a standard frequency, which may not be adequate for some sites, EPA clarifies that the Director has di scretion to require more frequent AoR reevaluations based on site specific informa tion to ensure that USDWs are protected from endangerment.

EPA recognizes that there are many unknowns about how GS projects will unfold including: the practicalities of permitting, operating, monitoring, and closing a GS project. To address this, the Agency is using an adaptive approach to regula ting GS. The Agency plans, every six years, to collect and review data on GS projects to dete rmine whether the appropriate amount and types of information and appropriate documentation are being collected, and to determine if modifications to the requirements are appropriate or necessary.

EPA disagrees that an annual reevaluation of th e AoR is appropriate, because this timeframe would not, in many cases, allow for the generatio n and collection of sufficient data on which evaluate modeled predictions. However, EPA adds that the Director ha s discretion to require more frequent reevaluations based on site speci fic information such as when monitoring data differ significantly from modeled predictions, or when there are appreciable operational changes (e.g., injection rates).

EPA adds that the final GS rule includes provisi ons that owners or operators review and update the AoR and corrective action plan throughout the lif e of the project, as specified in §146.84(c). Owners or operators must review the plan and identify necessary amendments to the plan or

demonstrate to the Director that no amendment is needed. The review must be performed within one year of an AoR reevaluation, following any significant changes to th e facility (e.g., the addition of monitoring or inject ion wells), or when required by the Director. EPA believes that these new provisions could addres s the commenter’s suggestions.

Letter ID: 0250 Comment ID: 22309 Letter Lines: 876 to 892

Comment Code: 3700 2.2.5 Comments on the requirement for an AoR and corrective action plan

Comment Code: 4750 2.7.5 Comments on the merit of a nnual reports (seeking comment)

Comment: The rule should require updating when wa rranted of all of th e proposed "plans" and should require an annual report that summarizes whether not updates have been warranted, and whether or no t updates have been undertaken

We applaud EPA for proposing to requi re the creation, use, and updating of various "plans" during the operating life of a facility. By creating such an iterative process, and basing it on monito ring and other operati onal data that

38become available through time, EPA can assu re that facilities are managed in a way that adapts to changing circumstances. This approach also has the potential

to enable what the Preamble calls an "ongoing dialogue" between operators and regulators, especially if the rule is enhanced by the annual reporting requirement suggested below for inclusion in §146.91.

Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

Individual Response: EPA acknowledges the commenters' s upport of the AoR and corrective action plan, and retains the requi rement in the final regulation §146.84(b). EPA believes that the iterative process by which monitori ng and operational data are used to validate the original AoR calculation, along with the combined knowledge and ongoing dialogue between the owner or operator and the Director on the local geologic co nditions will be critical in developing and implementing plans that protec t USDWs from endangerment.

EPA adds that the final rule in cludes provisions that owners or operators review and update the AoR and corrective action plan, th e testing and monitoring plan, a nd the emergency and remedial response plan throughout the life of the proj ect, as specified in §146.84(c), §146.90(j), and §146.94(d). Owners or operators must review each plan and identify necessary amendments to the plan or demonstrate to the Director that no amendment is needed. These reviews must be performed within one year of an AoR reeval uation, following any significant changes to the facility (e.g., the additio n of monitoring or injection wells), or when required by the Director.

EPA clarifies that the final rule does not require an annual report.

Letter ID: 0250 Comment ID: 22310 Letter Lines: 889 to 896

Comment Code: 4610 2.6.1 Testing and monitoring plan requirement (seeking comment)

Comment: Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the testing and monitoring plan re quired by §146.90 (the ambiguous word "maintain" is used and there appears to be no requirement that estimated plugging costs be kept current);

Individual Response: EPA agrees that developing and follo wing testing and monitoring plans is an important part of assuring th at a GS project is operating prope rly and is crucial for the early detection of potential endangerment to USDWs. EPA also agrees that periodic updates to the plan are appropriate. EPA clarifies that the fina l GS regulation includes a requirement that the

AoR be reevaluated at least ever y 5 years, and it specifies at § 146.90(j) that the operator revise

39the testing and monitoring plan to incorporate the results of the most recent AoR reevaluation and recent operational and monitoring data.

Letter ID: 0250 Comment ID: 22311 Letter Lines: 889 to 892 ; 897 to 898

Comment Code: 5100 2.8.1 Injection well plugging activ ities (seeking comment) (40 CFR 146.92)

Comment: Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the plugging plan required by §146.92 (again the ambiguous word "maintain" is used);

Individual Response: EPA believes that developing and implementing an injection well plugging plan is important to assuring that GS wells are plugged in a manner that will ensure that

the well will not serve as a conduit for CO2 leakage, preven ting endangerment of USDWs.

EPA disagrees that explicit requirements to ma ke updates to the injection plugging plan is necessary. The final rule at §146.92(c) requires the owner or operat or to notify the Director of any changes to the injection well plugging plan at least 60 days before plugging the well. This will allow the owner or operator (through communication with the Director) to address any

issues associated with the in itial well plugging plan submitted with the permit application and will require the owner or operato r to maintain the plugging plan in order to communicate such changes. EPA is not requiring formal periodic review and updates to th e injection well plugging plan throughout the injection pha se. EPA does not expect that ch anges to this plan would be implemented until injection operations cease.

Letter ID: 0250 Comment ID: 22312 Letter Lines: 889 to 892 ; 899 to 904

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

Comment: Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the post- injection site care and s ite closure plan re quired by §146.93 (not only is the word "maintain" used, but the ambiguity inherent in this term is revealed by the instruction in §146.93(a)(3) to consider amendments to this plan "upon cessation of injection" - §146.93 might be read to mean that operators could "maintain" this particular plan simply by considering the need for

amendment on one occasion over the life of the facility); and

40Individual Response: EPA believes that developing and impl ementing a post-injection site care and site closure plan is important to ensure protection of USDWs, and agrees that the plan should

be revised as needed to account for the most r ecent information about the site. EPA anticipates that, in some cases, the appropriate post-injectio n monitoring strategy may end up being different than initially projected and ther e may be a need to amend the pos t-injection site care and site closure plan. EPA is requiring that upon the cessa tion of injection, the owner or operator submit an amended post-injection site car e and site closure plan or dem onstrate to the Director that no changes to the original post-injection site care and site closure plan are necessary, as specified in §146.93(a)(3). EPA is not requiring formal periodic review and updates to the PISC and site closure plan throughout the injecti on phase. EPA does not expect that changes to this plan would be implemented until injection oper ations cease. EPA envisions th at owners or operators would

take into account similar cons iderations that guide updates to other project plans, e.g., monitoring and operational data and results of AoR reevaluati ons. EPA adds that, if any monitoring or other site data in dicate a need for amending the pos t-injection site care plan, the owner or operator is expected to amend the plan accordingly.

Letter ID: 0250 Comment ID: 22313 Letter Lines: 889 to 892 ; 905 to 907

Comment Code: 5800 2.13 Comments on emergency and re medial response (40 CFR 146.94)

Comment: Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the emergency and remedial response plan required by §146.94 (there is no requirement here that the plan be updated as warranted - there is not even a requirement that the pl an be "maintained."

Individual Response: In response to comments on the need for revision of the emergency and remedial response plan, EPA has added a re quirement at §146.94(d) requiring owners or operators to review their emer gency and remedial response plans within one year of an AoR reevaluation or following significant changes to the facility. Subsequently, the owners or operators must submit an amended plan or demons trate to the Director that no amendment to the plan is needed.

Letter ID: 0250 Comment ID: 22314 Letter Lines: 909 to 932

Comment Code: 4750 2.7.5 Comments on the merit of a nnual reports (seeking comment)

Comment: An additional annual reporting requiremen t will enhance the ability of both Director and operators to keep track of which plans require updating and whether or not plans that ought to be updated have in fact been revised. Such a shared understanding is essential if there is to be the "ongoing dialogue" between

41regulators and operators that EPA an ticipates. Our Environmental NGO Group considered supporting the inclusion of an annual report as described in the preamble at 73 Fed. Reg. 43518, but conclude d that the benefits of that particular report would be outweighed by the burden. The annual report we are suggesting here, however, would be much simpler. We believe that EPA should require a report, signed by the a ppropriate company official, that:

• lists all of the required plans; • confirms for each plan that the comp any has reviewed all monitoring and operational data since the previous annual re port that is releva nt to a decision on whether to update the plan; • states with regard to each plan wh ether an update was determined to be warranted; and • for those plans where the operator did d ecide that an update was appropriate, a statement that the update has or has not been completed and a summary of the

modifications that have been made.

The rule should further provide that th e Director has authority to require submission of copies of updated plans and/ or further information regarding the reasons why updates of particular pl ans have or have not been done.

Individual Response: The final GS regulation retains the reporting requirements as proposed and does not include a requirement for an annua l report. Instead, EPA believes that periodic reevaluation of the AoR, as re quired at §146.84(e), along with any re visions to the required plans that may be required based on the AoR reevaluation, will promote an ongoing relationship between the permitting authority and the owner or operator. The final GS rule, at §§146.84(c), 146.90(j), and 146.94(d), requires owners or oper ators to review and update the AoR and corrective action plan, the testi ng and monitoring plan, and the emergency and remedial response plan throughout the lif e of the project.

Regarding the content of the reports on the updates, owners or operators must review each plan and identify necessary amendments to the plan or demonstrate to the Dire ctor that no amendment is needed. These reviews must be performed w ithin one year of an AoR reevaluation, following any significant changes to the facility (e.g., the addition of monitoring or injection wells), or when required by the Director. In no case can reviews occur less often than once every five years. For additional information, please see the fi nal rule and the preamble for a discussion of EPA's final approach to r ecordkeeping and reporting.

While the Agency recognizes some concerns expressed by commenters about the burden associated with an annual report, the Agency 's decision to retain the semi-annual reporting requirement at §146.91(a) is because the semi-annua l report in conjunction with the continued dialogue associated with AoR r eevaluations and periodic updates to the plans is a preferred approach to an annual report.

Letter ID: 0250 Comment ID: 22315 Letter Lines: 934 to 943

42Comment Code: 3824 2.3.1.2 Cementing of long-string casing (seeking comment)

Comment: Cementing requirements for casings

§146.86(b)(3) requires the long string casi ng to be cemented by circulating cement to surface in one or more stages. It has come to our attention that may be hard to accomplish in some cases, such as very deep wells. We have also been alerted to disadvantages of this approach with regard to the weight of the cement column and its relation to well integrity. We urge EPA to fully consider the advantages and disadvantages of this approach. At a minimum however, the long string casing should be cemented to at least above the confining layer (caprock).

Individual Response: Section 146.86(b)(3) requires that th e long-string casing extend to the injection zone and be cemented by circulating ce ment to the surface in one or more stages. It does not, however, specify how cementing would be accomplished, and gives flexibility to the owner or operator to propose alternate methods to provide a sufficient amount of cement to meet the standard that USDWs are pr otected from endangerment, s ubject to the approval of the

Director. EPA notes that there ar e many potential ways to meet the requirement in deep wells, such as the use of staged cementing. See th e discussion of Class VI well construction requirements in the preamble to the final GS rule for additional information. Additionally, EPA is developing guidance on the construction of Class VI wells. This guidance will be available on EPA’s website at http://water.epa.gov/type /groundwater/uic/we lls_sequestration.cfm.

EPA adds that cementing of deep wells has been performed successfully in the past, for example, by owners or operators of Class I hazardous and Cl ass I municipal waste disposal wells. Some of these wells, which must meet the same cemen ting requirements for long-string casing as Class VI wells, are up to 12,000 feet deep (EPA, 2001).

EPA also received comments from stakeholders representing states, a water association, and industry supporting this provisi on, saying that it provides, at a reasonable cost, corrosion protection of the casing; prevents undesirable migration of fluids be hind the casing; provides support to the casing; and provides multiple barriers against endangerment of USDWs.

EPA stresses that protection of USDWs is the primary mission and mandate of the UIC program and the purpose of all requirements for inject ion wells. Any injection activity must be demonstrated to not endanger USDWs, regardle ss of their depth, and if such non-endangerment cannot be shown, then the activity will not be allowed under UIC requirements or the SDWA.

EPA recognizes concerns regardi ng construction of Class VI wells where the lowermost USDW is very deep. To further address comments on d eep injection wells, the final GS rule at §146.95 includes requirements for owners or operators that seek a waiver of the injection depth requirements. Owners or operators of wells opera ting under injection depth waivers must comply with additional construction require ments to ensure that wells used to inject above or between USDWs are protective. See the discussion of the wa iver approach in the preamble to the final GS

rule for additional information.

43Letter ID: 0250 Comment ID: 22316 Letter Lines: 945 to 956

Comment Code: 3866 2.3.3.3 Logging and testing requirements (40 CFR 146.87)

Comment: Cement bond logs and other outdated met hods are not sufficient for establishing cement quality and integrity

Some of the techniques listed in §146 .87(a)(2)(ii) and §146.87(a )(3)(ii), such as cement bond and variable density logs are no longer state-of -the-art, and do not reveal the nature or shape of a ny voids in the cement - instead they represents an average estimate of void space. To verify the inte grity of cement behind casings, including the location of any channels, contamination or missing cement, the Director should require "a cement map that incorporates data from a cement bond log, a variable density display, and an ultrasonic image, unless an alternative evaluation based on equivale nt or better technologies has been approved in writing".

Individual Response: EPA has conducted extensive research and has found that the tests and logs specified at §146.87(a)(2 and 3) have been proven through i ndustry practice and research to identify cementing flaws. EPA also believes th at the required logs are sufficient to show potential pathways for migration of fluid into and out of the wellbore. EPA adds that should alternative methods be shown to provide equivale nt or better information, the Director may allow such alternatives under §146.87(a)(5). The Agency plans to, every six years, collect and review data on GS projects to determine whether the appropriate amount and types of information and appropriate documentation are being collected, and to determine if modifications to the requirements are approp riate or necessary.

Letter ID: 0250 Comment ID: 22317 Letter Lines: 958 to 969

Comment Code: 4610 2.6.1 Testing and monitoring plan requirement (seeking comment)

Comment: Monitoring

In §146.90 the proposed rule outlines requirements for testing and monitoring. We strongly support the inclusion of such provisions. Monitoring is central to verifying and adapting the operational para meters of a GS project, while the concept of GS cannot be simply based on the premise of confinement without verification. We also support the prov isions calling for a testing and monitoring plan, although we have suggest ed above that the requirements for updating this plan be strengthened. The collection of baseline data and information prior to the commencement of operations is also necessary for a number of monitoring tec hniques to produce useful re sults, and should be preserved.

Individual Response: EPA agrees with commenters that developing and following testing and

44monitoring plans is an important pa rt of assuring that a GS projec t is operating properly and is crucial for the early detection of potential enda ngerment to USDWs. EPA also agrees that periodic updates to the plan are appropriate. EP A clarifies that the fina l GS regulation includes a requirement that the AoR be reevaluated at least every 5 years, and it speci fies at §146.90(j) that the operator revise the testing and monitoring plan to incorporate the results of the most recent AoR reevaluation and recent operational and monito ring data. EPA adds that the final rule, at §146.82, retains the data collection requirements th at are part of the permit application.

Letter ID: 0250 Comment ID: 22318 Letter Lines: 971 to 982

Comment Code: 4600 2.6 Proposed Plume and Pressure Front Monitoring Requirements (40 CFR 146.90)

Comment: The proposed rule outlines several differe nt types of monitoring requirements: (a) analysis of the CO2 st ream; (b) continuous monitori ng of injection pressure, rate and volume as well as other quantit ies; (c) corrosion monitoring for the well materials; (d) groundwater and geochemistry monitoring above the confining zone; (e) mechanical integrity testing; (f) pressure fall-off tests;(g) CO2 plume and pressure front tracking; and (h) surface air monitoring.

We do not wish to comment on (c). We cons ider subpart (i), en abling the Director to require additional forms of monitoring, as well as subpart (j), calling for a quality assurance and surveillance plan, en tirely appropriate. We consider (a), (b), (d), (e), and (f) and (g) to be essential elements of a sound monitoring

system.

Individual Response: EPA acknowledges the commenter’s s upport. Based on its evaluation of all public comments 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 approach.

EPA agrees with commenters on the importance of monitoring at GS sites and emphasizes that monitoring of injection activit ies will be an important comp onent of every GS project. Monitoring associated with injection wells and th e movement of the CO2 plume is necessary to verify that the injectate is confined in the target formations and does not endanger USDWs.

Letter ID: 0250 Comment ID: 22319 Letter Lines: 984 to 1010

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

Comment Code: 4600 2.6 Proposed Plume and Pressure Front Monitoring Requirements (40 CFR 146.90)

Comment: In particular, monitoring above the caproc k, sometimes informally referred to as "above-zone monitoring, and covered in (d), is a tested monitoring method [FN23], and one that can be key to verifying the inte grity and lateral extent of the caprock

45(or confining zone). We support its inclus ion, but also recogni ze that it might not be necessary to employ this method ev ery time. We would only consider its omission acceptable only if another method capable of testing and verifying the integrity of the confining zone is bein g used. Subpart (d) would also cover groundwater monitoring near the surface, at a long distance from the caprock. It is our understanding that re searchers from the Lawrence Livermore National Laboratory are already confident in the mer its of this approach and its accuracy in detecting small amounts of CO2. We therefore recommend the following minor changes to §146.90(d):

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Periodic monitoring of the ground water qua lity and GEOPHYSICAL, geochemical OR OTHER changes above the confining zone(s) that may be a result of carbon dioxide

OR OTHER INDUCED fluid movement thr ough the confining zone or additional identified zones; provided however that the DIRECTOR MAY INSTEAD REQUIRE THE

INCLUSION OF OTHER METHODS THAT TEST AND/OR VERIFY THE INTEGRITY OF

THE CONFINING ZONE(S) WITH SIMILAR ACCU RACY AND TO THE SAME OR LARGER

AREAL EXTENT.(1) [...]"

[FN23: Used successfully at the Frio pilot project, and already being considered for other projects.]

Individual Response: EPA clarifies that direct monitori ng of ground water quality above the confining zone is important, and the GS rule requires this at §146.90(d). EPA believes that the ground water geochemical monitoring outlined in §146.90(d) will maximize protection of USDWs from endangerment at GS sites. Additional monitoring above the confining zone, as well as monitoring in additional formations, e.g., the injection zone, may also be necessary, and if the Director believes such monitoring is wa rranted he/she has the au thority under §146.90(i) to require that it be included in the testing and monitoring plan.

EPA adds that the baseline geochemical data required with the permit application at §146.82(a)(6) will provide information on predicting potential interactions between rocks and CO2 as the commenter suggests, and also expects that this information will inform the development and approval of a site-specific te sting and monitoring plan. EPA expects that the data will also help determine whether any ch anges are occurring above the confining zone and whether they might be associated wi th the CO2 plume or pressure front.

EPA further clarifies that the fi nal rule at §146.90(g) requires i ndirect monitoring not above the confining zone but in the injec tion zone, unless the Director de termines, based on site-specific geology, that indirect methods are not appropria te. Indirect methods can include geophysical

methods.

46Letter ID: 0250 Comment ID: 22320 Letter Lines: 1012 to 1022

Comment Code: 4655 2.6.5.1 Plume tracking techniques/ geophysical methods (seeking comment)

Comment: We also strongly support monitoring to tr ack the CO2 plume. There is no unique method for doing this, and we do not believ e that 4D-seismic techniques are appropriate or effective in all geologic se ttings, or that they should be made mandatory. However, tracking the extent of the CO2 plume is generally possible and must be part of a comprehensive a nd credible monitoring plan and a GS project. Appropriate limits of accuracy will be needed, as neither tracking individual CO2 molecules, nor to the near est inch are feasible or desirable. However, the monitoring resolution must be such so as to enable confinement to be established, to give regulators confid ence that the CO2 and displaced fluids are not near potential leakage pathways, a nd to warn in advance of any remedial action that might be needed.

Individual Response: EPA agrees that seismic monitoring ma y not be applicable or appropriate for all sites. The final rule (a t §146.90(g)) requires owne rs or operators to perform monitoring to track the extent of the CO2 plume and pressure front. The owner or operator must use direct methods to monitor for pressure changes in the injection zone. Indirect methods (e.g., seismic, electrical, gravity, or electromagnetic surveys an d/or down-hole CO2 det ection tools) are also required unless the Director determines, based on site-specific geology, that such methods are not appropriate.

EPA is affording Director's disc retion regarding the use of geophys ical techniques at some sites because the Agency recognizes that geophysical methods are not appropriate in all geologic settings. For example, geophysical methods are diffi cult to execute in areas that are structurally and topographically complex or where lithologies have limited contrast in density, porosity, permeability, and other physical properties. EPA clarifies that this determination will be made by the Director based on the site-specific geologi c information submitted by the owner or operator with their permit application.

There may also be interference from urban and re sidential infrastructure, and sites with loose materials such as glacial deposits may produce poor or inaccurate seismic images. But the laterally continuous, confined formations that that make many sites appropriate for GS will also render many of them suitable for seismic survey ing. In fact, seismic and other geophysical and remote sensing methods have been used with suc cess at GS pilot projects and are likely to be useful for plume tracking at many GS sites. St atOilHydro has used both time-lapse seismic and gravity methods to track the CO2 plume at the Slei pner site. Seismic surveys have also been used successfully at the Weyburn pilot project site in Saskatchewan. Although resolution on seismic surveys is generally accepted to be the best of the geophysical methods, gravity monitoring at Sleipner has also imaged the plume, and results have agreed with seismic surveys. At InSalah, PSInSAR satellite monitoring has been used in co mbination with tiltmeter data and was able to detect otherwise imperceptible ground displacement (i.e., at the millimeter scale) that indicates

47the presence of CO2.

EPA acknowledges the commenters' concern about th e cost of geophysical techniques. However, EPA believes that tracking of the plume is essential for protection of USDWs from endangerment at GS sites and that geophysical methods are necessary for such tracking.

EPA is developing guidance on testing and mon itoring to assist owne rs or operators and Directors in evaluating requi rements under §146.90, including pr oposed monitoring plans. The guidance describes available technologies a nd recommended approaches for implementing a testing and monitoring plan, including pre-ope rational geophysical l ogging and testing of injection wells, MITs, injecti on well testing during operation, groundwater quality monitoring, tracking the CO2 plume and pressure front, a nd soil gas and surface air monitoring which may be required by the UIC Director for specific GS projects. Th e guidance can be found on EPA’s website at http://water.epa.gov/type/gr oundwater/uic/wells_se questration.cfm.

Letter ID: 0250 Comment ID: 22321 Letter Lines: 1024 to 1038

Comment Code: 4650 2.6.5 CO2 plume and pressure fr ont tracking (seeking comment)

Comment: The "position of the pressure front" is not something that is as straightforward to establish as the extent of the CO2 pl ume. As we have commented above, there is no distinct "front", or discontinuity, but rather a gradient in pressure that dissipates with distance away from th e injection zone. Estimating the total injection footprint therefore will require appropriate thresholds to be defined

in order to estimate the area of elevated pressure. Additiona lly, methods such as seismic surveys do not work in the same way for compressed brine as they do for CO2rich brine. Tracking the extent of the CO2 plum e is generally possible and must be part of a comprehensive a nd credible monitoring plan and a GS project. The extent of the area of elev ated pressure will likely be estimated

with a combination of meas urements, inferences and m odeling, but it is presently essential to have monitoring wells penetr ating the confining zone to do this. Where the CO2 plume itself is concerned, rather than the ar ea of elevated pressure, the role of measurements (inc luding indirect measurements such as seismic surveys) will and should be far greater than that of modeling.

Individual Response: EPA agrees with commenter that plume tracking must be part of a comprehensive and credible monitoring plan for GS wells. For this reason, EPA believes that direct pressure measurements are appropriate and that direct pre ssure monitoring will be feasible at all GS sites. The final rule, at §146.90(g), requ ires owners or operators to perform monitoring to track the extent of the CO2 plume and pressure front. The owner or oper ator must use direct methods to monitor for pressure changes in the injection zone. Indirect methods (e.g., seismic, electrical, gravity, or electromagnetic surveys an d/or down-hole CO2 det ection tools) are also required unless the Director determines, based on site-specific geology, that such methods are not appropriate.

EPA believes that pressure monitoring in th e injection zone is n ecessary to track the

48development and movement of the pressure front and CO2 plume. Monitoring can also identify needed remedial actions, provide inputs for AoR reevaluation m odeling, evaluate predictions of plume movement, and target additional geoche mical and surface monitoring needs. Knowledge of the location of the CO2 plume and the associated pressure front will assure the public that GS projects are proceeding according to plan, provide sufficient information to the owner or operator and Director, or allow for appr opriate actions to address any indication that USDWs may be endangered.

EPA is developing guidance on testing and mon itoring to assist owne rs or operators and Directors in evaluating requirements under §146.90, which will include discussion of identifying the extent of the CO2 plume and pressure front . The guidance describes available technologies and recommended approaches for implementing a testing and monitoring plan, including preoperational geophysical logging and testing of injection wells, MI Ts, injection well testing during operation, groundwater qualit y monitoring, tracking the CO2 plume and pressure front, and soil gas and surface air monitoring which may be required by the UIC Director for specific GS projects. The guidance can be found on EPA’s website at http://water.epa.gov/type/groundwat er/uic/wells_sequestration.cfm. In addition, in January 2009, DOE published a best practices manual entitled "Monitoring, Verificat ion, and Accounting of CO2 Stored in Deep Geologic Formations" (DOE/NETL-311/081508); this manual is included in

the docket for the for the final GS rule.

Letter ID: 0250 Comment ID: 22322 Letter Lines: 1040 to 1043

Comment Code: 4670 2.6.7 Surface air monitoring and/or soil gas monitoring (seeking comment)

Comment: Finally, surface air monitoring techniques w ill not always be necessary for GS projects. As with other monitoring methods , they may work well in particular settings but not in others (for exam ple where distinguishing from natural variability or from baseline data is ha rd). Current scientific thinking also

Individual Response: EPA acknowledges that air and soil ga s monitoring are subject to sitespecific limitations and may not be suitable in all settings as a me thod to ensure USDW protection. However, EPA does not believe that this should entirely preclude their use. If surface monitoring were the only monitoring method employed to ensu re USDW protection, direct

correlation of CO2 at the surface with CO2 in th e subsurface might be difficult; however, when combined with information gathered through othe r monitoring techniques required of GS well owners and operators (e.g., monitoring wells, geophysical te chniques), air and soil gas monitoring may provide valuable data on the magnitude and location of a leak.

The final rule at §146.90(h) retains the allowance for surface air and soil gas monitoring at the

discretion of the Director as a means of identif ying leaks that may pose a risk to USDWs and informing emergency notification of a Class VI ow ner or operator and UIC Director in the event of a USDW endangerment, pursu ant to requirements at §146.91(c). EPA cl arifies that the decision to use surface monitoring and the selecti on of monitoring methods will be site-specific

49(e.g., may be influenced by geology, injection depth, and operational conditions) and must be based on potential risks to USDWs within the AoR.

Letter ID: 0250 Comment ID: 22324 Letter Lines: 1043 to 1050

Comment Code: 4650 2.6.5 CO2 plume and pressure fr ont tracking (seeking comment)

Comment: variability or from baseline data is ha rd). Current scientific thinking also dictates that the CO2 plume and confin ement are best monitored near the injection zone or right a bove the caprock. This implies far greater depths, and a much larger distance between CO2 and disp laced fluids from US DWs. The Director

should have the discretion to require such techniques , but we do not believe that they should be made mandatory fo r all permits nor should the rule be limited to listing specific techniques (w hich might be superseded or have preferable alternatives).

Individual Response: EPA has changed this requirement in the final rule. The final GS regulation, at §146.90(g)(1), requires all GS project owners or opera tors to monitor for pressure changes in the injection zone. EPA believes that pressure monitoring in the injection zone is necessary to track the development and moveme nt of the pressure front and CO2 plume.

Pressure monitoring within the injection zone is necessary because any such monitoring above the confining zone would not de tect movement of the pressure front unless a breach of the confining zone occurs. EPA believes that monitori ng using wells in the inje ction zone (i.e., that penetrate the confining zone) can be safely performed if the wells are constructed to prevent flow between the injection zone a nd USDWs or other layers above the confining zone. Such construction technologies exist and have been us ed in the oil and gas industry for years. EPA believes that the benefits of monitoring in the injection formation outweigh the manageable risk of those monitoring wells serving as conduits for fluid movement. EPA adds that owners or operators may consider performi ng additional pressure monitoring in wells that are above the confining zone (e.g., in the same wells used to perform ground water quality monitoring required at §146.90(d)) to provide additional verification that no pressure ch anges are occurr ing above the confining zone due to CO2 leakage. Monitoring al so identifies needed re medial actions, provides inputs for AoR reevaluation modeling, and ta rgets additional geochemical and surface monitoring needs. Knowledge of th e location of the CO2 plume and the associated pressure front will assure the public that GS projects are proceeding according to plan, provide sufficient information to the owner or operator and Director, or allow for appropriate actions to address any

indication that USDWs may be endangered.

Flexibility is also provided re garding how to monitor for the sp ecific data required by the final rule. The testing and monitoring plan is develope d by the owner or operato r in consultation with the Director and is designed to ensure that a detailed, Director-approved document describing how monitoring will be conducted during the lifetime of the project exists. EPA is developing guidance on testing and monitoring to assist owners or operators and Directors in evaluating requirements under §146.90, includi ng proposed monitoring plans. The guidance describes available technologies and reco mmended approaches for implem enting a testing and monitoring

50plan, including pre-operational geophysical logging and testin g of injection wells, MITs, injection well testing during ope ration, groundwater quali ty monitoring, tracking the CO2 plume and pressure front, and soil gas and surface ai r monitoring which may be required by the UIC Director for specific GS projects. The guidance can be found on EPA’s website at http://water.epa.gov/type/groundwater /uic/wells_sequestration.cfm.

Letter ID: 0250 Comment ID: 22325 Letter Lines: 1052 to 1086

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

Comment Code: 4650 2.6.5 CO2 plume and pressure fr ont tracking (seeking comment)

Comment: To capture the points made above and resolv e current inaccuracies or limitations in the proposed language, we recommend the following additional changes in §146.90(g):

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf, to see the original formatting.]

"(1) Testing and monitoring to track ESTABLISH the extent of the carbon dioxide plume and the position of the pressure front WITHIN DEFINED THRESHOLDS, WITH THE ASSISTANCE OF MODELING TOOLS WHERE

APPROPRIATE AND THROUGH DIRECT MEASUREMENTS OR INDIRECT, GEOPHYSICAL OR OTHER TECHNIQUES by either monitoring for pressure changes in the first formation overlying the confining zone or using indirect, geophysical techniques (e.g., s eismic, electrical, gravity, or electromagnetic surveys and/or down

- hole carbon dioxide detection tools); (2) TESTING AND MONITORING TO ESTABL ISH THE EXTENT OF THE AREA OF

ELEVATED

PRESSURE THROUGH DIRECT MEASUREMENTS AND THE ASSISTANCE OF

MODELING TOOLS."

and in §146.90(h):

[In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf, to see the original formatting.]

"At the Director’s discretion, surface air monitoring METHODS and/or soil gas monitoring to detect movement of car bon dioxide that could SIGNAL endangerMENT OF a USDW. (1) The testing and monitoring plan must be based on potential vulnerabilities within the area of review; (2) The monitoring frequency and spatial distribution of surface a ir

51monitoring and/or soil gas monitoring must reflect baseline data and the monitoring plan must include how the proposed monitoring w ill yield useful

information on the area of re view delineation and/or co mpliance with standards

under 40 CFR 144.12"

Individual Response: As described above, EPA believes that direct pressure measurements are appropriate and that direct pressure monitoring w ill be feasible at all GS sites and retains this provision in the final GS rule, at §146.90(g).

EPA acknowledges that air and soil gas monitoring to ensure USDW protec tion is not necessary at all GS sites and agrees that the decision to use surface monitoring and the selection of monitoring methods for the purpose of US DW protection will be site-specific.

The Agency believes that surface air and soil ga s monitoring, when coupled with subsurface monitoring, may be appropriate at some GS projects to ensu re USDW protection. EPA also acknowledges that surface air a nd soil gas measurements are subj ect to variabili ty and may not be suitable in all settings as a method to ensure USDW protection. However, EPA does not believe that this should entirely preclude thei r use. The decision to use surface monitoring and

the selection of monito ring methods will be site-specific (e.g., may be influenced by geology, injection depth, and operational conditions) and must be based on poten tial risks to USDWs

within the AoR.

In the final rule, at §146.90(h), the decision to re quire such monitoring as an additional measure to ensure USDW protection rests with the Direct or as a means of identif ying leaks that may pose a risk to USDWs and informing emergency notifi cation of a Class VI owner or operator and UIC Director in the event of a USDW endangerm ent, pursuant to requirements at §146.91(c).

Based 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 discussi on on EPA's final approach.

Letter ID: 0250 Comment ID: 22326 Letter Lines: 1088 to 1115

Comment Code: 1620 1.3.2 Induced seismicity

Comment Code: 3100 2.1 Proposed Geologic Siting Requirements (40 CFR 146.83)

Comment: Seismicity

Naturally occurring seismicity has been ci ted as an area of concern for geologic sequestration of CO2. We do believe that seismicity merits diligent treatment both in the regulations and in project operation, but we see no need for a blanket ban of sequestration in seismica lly active areas. Alth ough some sites - especially ones near major active faults - would not be advisable for injection, there are plenty of other sites in seis mically active areas that would make

excellent candidates for safe and effec tive sequestration. Moreover, tools to measure, predict and design against the effects of seismic activity are

52available.

Nature has proven its ability to retain fluids trapped in the subsurface in seismically active areas in many instances over hundreds of millions of years, even in highly tectonically active regions of the country such as California. The potential for slippage for faults to cr eate leakage pathways to USDWs or the surface can be managed and effectively minimized through careful siting and operational design using well-established tools and methods. The regulations

should ensure that suitable sites are se lected, while high risk areas, such as those near major, non-sealing faults or those that demonstrate frequent activity, are rejected. The most likely potential CO2 leakage paths would be injection wells, and not faults. However, these can be desi gned to prevent leakage and to be resilient to earthquakes.

We regard a ban on sequestration in seis mically active areas unwarranted. We do however believe that additional diligence is required in site characterization and selection in such areas. The requir ement in §146.82(c)(3) should be modified

as follows:

Individual Response: EPA agrees that GS should not be banned in any type of environment or geologic setting and believes that decisions about seismic risk s hould be made on a site-specific basis. The Class VI requirements to properly ch aracterize, permit, operate, and monitor a GS project are designed to ensure that, where GS is employed, it is done in a manner that protects USDWs from endangerment. These requirements include site characterization during which owners or operators must submit information a bout the seismic history of and seismic sources near a proposed GS site, as well as data on known or suspected faults in the AoR, geomechanical information on fractures, stress, ductility, rock strength, and in s itu fluid pressures within the confining zone as specified in §146.82(a)(3). This information is evaluated by the Director in conjunction with information a bout well construction, operation, m onitoring, post-injection site care, and other site-specific information. The Di rector determines suit ability of a potential project site for GS. Sites with the potential for reopening or react ivation of faults or unacceptable

seismic risk that could otherwise interfere with containment would not be suitable for GS sites – as owners or operators seeking to inject CO2 for GS at such sites would not be able to demonstrate USDW protection from endangerment.

EPA acknowledges that wells in the AoR are pot ential leakage pathways , and the GS rule contains rigorous provisions for both injecti on well construction at §146.86 and corrective action

on active or abandoned wells lo cated in the AoR at §146.84.

Letter ID: 0250 Comment ID: 22327 Letter Lines: 1117 to 1134

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

Comment Code: 1620 1.3.2 Induced seismicity

Comment: [In the paragraph below the text

in all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf, to see the

53original formatting.]

"Information on seismic history including the presence and depth of seismic

sources and aN ASSESSMENT OF that WHETHER SUCH seismicity would not interfere with containment;"

In addition, language should be added to the minimum criteria for siting in §146.83, clarifying that if induced or na tural seismicity poses unacceptable risks, a permit will not be granted. In order properly to assess the risk of significant induced seismicity in light of permitted operating conditions, the rule may need to require applicants to submit information beyond what is currently required in propos ed §146.82. The effects of any seismic events during project operation should also be ta ken into account when updating, or considering whether to update, the Area of Review and Corrective Action Plan, the Testing and Monitoring Plans, and the Emergency and Remedial Response Plans, as well as any other plans as necessary.

Individual Response: Based on its evaluation of all public comments 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 discussion of geologi c site characterization for further discussion on EPA's final approach.

EPA clarifies that under §146.82(a) (21), the Director has the au thority to require additional information to be submitted with the permit appl ication. EPA agrees that seismic events should be taken into account when updating the plans or other permit conditions and clarifies that existing language at §144.39(a)(2) allows the Dir ector to modify the permit when he or she

receives new information that was not av ailable at the time of permit issuance.

Letter ID: 0250 Comment ID: 22328 Letter Lines: 1136 to 1146

Comment Code: 1000 1. General and Administrative Comments

Comment: F. Conclusion

Our Environmental NGO Group appreciates th e opportunity to provide comments to EPA on this most important rulemaking e ffort. A final rule will represent a significant step forward in combating gl obal climate change, and the time is more than ripe for the U.S. to take such steps. When EPA issues its final rule, we feel it must be both technically sound and adaptive to reflect learning from experience with GS projects in as seamless a manner as is possible. We very much look forward to continuing to work with the Agency on this rule, as well as other efforts under the Agency’s existing authority to addres s the significant problem of climate change in the near term.

Individual Response: EPA acknowledges the comment. Pleas e see the remainder of EPA's

54responses to this comment letter for further de tails. For additional information on EPA's final regulatory approach, please see the final rule and preamble as well as the rulemaking docket.

Letter ID: 0250 Comment ID: 24726 Letter Lines: 30 to 66

Comment Code: 1000 1. General and Administrative Comments

Comment: Comments of:

Clean Air Task Force

Clean Water Action

Environmental Defense Fund

Natural Resources Defense Council

Western Resource Advocates

A. Introduction

The Clean Air Task Force, Clean Wate r Action, Environmental Defense Fund, Natural Resources Defense Council, and We stern Resource Advocates (Environmental NGO Group) thank EPA for the opportunity to comment on the Proposed Rule on carbon dioxide sequestration wells under th e Underground Injecti on Control (UIC) Program.

Founded in 1996, the Clean Air Task Force (CATF) is a nonprofit organization dedicated to restoring clea n air and healthy environm ents through scientific research, public education, and legal advocacy.

Founded in 1972, Clean Water Action (CWA) has 1.2 million members and offices in

20 states. Clean Water Action works to im prove public health and environmental protection through grassroots organizi ng, policy research and advocacy.

Environmental Defense Fund (EDF), founde d in 1967, is a non-profit organization that represents more than 500,000 members. EDF links science, economics and law to create innovative, equitable and cost -effective solutions to society’s most urgent environmental problems.

The Natural Resources Defense Counc il (NRDC) is a na tional, nonprofit organization of scientists, lawyers and e nvironmental specialists dedicated to protecting public health a nd the environment. Founded in 1970, NRDC has more than 1.2 million members and online activists nationwide, served from offices in New York, Washington D.C., San Francisc o, Los Angeles, Chicago and Beijing.

Western Resource Advocates (WRA) is a regional non-profit or ganization using law, economics and policy an alysis to protect the la nd, air and water of the

Interior Western United States.

Individual Response: EPA acknowledges the comment. Pleas e see the remainder of EPA's

55responses to this comment letter as well as the comments of EDF, and NRDC for further details. For additional information on EPA's final regula tory approach, please see the final rule and preamble as well as the rulemaking docket.

Letter ID: 0250 Comment ID: 25256 Letter Lines: 753 to 780

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

Comment Code: 3420 2.2.2.1 Scope of the inventory pr ocess (e.g., reliance on publicly available information, depth of wells)

Comment: [In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

§146.82(e): "A tabulation COMPILATION of all wells within the area of review which penetrate the injection or confining zone(s). TO SUPPLEMEN T AND/OR VERIFY INFORMATION OF PUBLIC RECORD, OPERATORS SHALL USE REASONABLE

METHODS TO IDENTIFY

THE PRESENCE WELLS WITHIN THE AREA OF REVIEW THAT PENETRATE THE

INJECTION OR CONFINING ZONE(S). Such data mu st include a desc ription [...]"

[FN22: NETL , for example, has developed an electromagnetic system that can be used for areal or ground-based identification of wells (casings).]

Additionally, we believe that problema tic wells may not be limited to the confining zone, as would be the case if confinement were to be breached, or if pressure effects caused by the injecti on caused fluid movement outside the defined confining zone. We recommend the following modifica tion in §146.84(c) (2):

[In the paragraph below the text in

all CAPS denotes added text. See al so EPA-HQ-OW-0390-0250.pdf to see the original formatting.]

"Using methods approved by the Director, id entify all penetrations, including active and abandoned wells and underground mine s, in the area of review that may penetrate the confining zone OR OT HERWISE ACT AS CONDUITS FOR FLUID

MOVEMENT

INSIDE OR OUTSIDE THE CONFINING ZONE".

Individual Response: EPA is retaining the requirement at §146.82(b), which is now found in §146.82(a)(4), as proposed. EPA adds that all corre ctive action must be pe rformed pursuant to the approved AoR and corrective act ion plan, which affords the Direct or the discretion to require any additional information needed (including info rmation that is not publ ically available) to

56ensure that all necessary corrective action is performed. EPA notes that the Director has the discretion at §146.84(c)(2) to requ ire the owner or operator to supplement a data records search—including the use of ground, airborne, or geophysical (e.g., magnetic) surveys—if there is reason to believe that the incompleteness of available information could compromise USDW protection from endangerment. For these reas ons, EPA is retaining the requirement at §146.84(c)(2) as proposed.

Regarding the concern about identifying wells other than those that penetrate the confining zone, EPA adds that the Director the discretion to requi re any additional information needed to ensure that all necessary corre ctive action is performed, including in formation on wells that are above the confining zone, if site-specific information in dicates such a need to ensure USDW protection.

Letter ID: 0250 Comment ID: 25257 Letter Lines: 889 to 896

Comment Code: 3500 2.2.3 Area of Review Reevaluation (seeking comment)

Comment Code: 4610 2.6.1 Testing and monitoring plan requirement (seeking comment)

Comment: Perhaps inadvertently, the proposed rule doe s not explicitly require updating of several of the required plans. In most but not all cases, th ere is a rather ambiguous requirement to "maintain" a give n plan. Explicit requirements to make updates as warranted appear to be missing from provisions relating to:

• the testing and monitoring plan re quired by §146.90 (the ambiguous word "maintain" is used and there appears to be no requirement that estimated plugging costs be kept current);

Individual Response: The final rule includes provisions th at owners or operators review and update the AoR and corrective act ion plan, the testing and monitoring plan, and the emergency and remedial response plan throughout the lif e of the project, as specified in §146.84(c), §146.90(j), and §146.94(d). Owners or ope rators must review each pl an and identify necessary amendments to the plan or demonstrate to the Director that no amendment is needed. These reviews must be performed within one year of an AoR reevaluation, following any significant changes to the facility (e.g., the addition of mon itoring or injection wells) , or when required by

the Director.

57