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.
Texas Pipeline Association

PlOtricl< J N\>gt<"

E,eclkvo lW""""

December 12, 2008

Water D<:>cket

Environmental Protection Agency

2822T

1200 Pennsylvania Avenue, N. W.

Washington, D.C. 20460

Re; TexltS Pipeline Association Comments on EPA's Proposed Rules Concerning

Carbon Dioxide Geologic Seguestration-D9ckctID No. EPA·HQ-QW-2008-Q390

Dear SirlMadam:

The Texas Pipeline Association ("TPA") appreciates the opportunity to submit these

comments on EPA's propolied rules under the Underground injection Control ("UIC') program

for carbon dioxide geologic sequestration wells. These rules were published in the Federal

Regi~'ler on July 25, 2008. Comments on the proposed rules are due on or belore o.:.::ember 24,

2008. Therefore, these oomments are timely.

TPA is a trade association whose members gather. cransport, and process nalUra] gas and

liquids through intrastate pipelines in Texas. Individual members orlhe TPA own and operate

numerous Class II injection wells, authorizing the injection of fluids in connection wilh

convenlional oil and gas prodllC1ion, enhanced oil and gas production and hydrocarbon storage

and retrieval. These injection wells are an integral part of oil and gas production and storuge in

Texas. In addition, TPA members may now or in the future seek to engage in experimental

technology wells or pilot projects for geologic sequestration of carbon dioxide. onder the Class V

injection well program. Similarly. TPA members in the future may ~k to engage in long term

geologic storage of carbon dioxide either by converting their existing Class II or V injection

wells to a (proposed) Class VI well or by drilling a new Class VI well for this pwpose.

Accordingly, TPA members will be affected by this proposed rule. ll>eir interest is to ensure the

protection ofthe existing authorizations onder the Class II and V injection well programs and to

ensure a smooth transition to a Class VI program.

TPA presents both general and specific comments to this proposed role as follows.

GENERAL COMMENTS

l. Development of a Claos VI injrdKlD well program should not impair or any way

modify cxisting autborizations for Class n injection welb.

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pt>one: (5'21478--2871 fax. (51,) 413-8416 E"""I oox..pipeIine.II~oI>oo.com
As rnentiono:d above. the oil and gas industry relies upon the aulhoriation provided by

the ClllSS II injcrtjoo "r~1I program for the disposal ofacid or gas. cnhanl:ed oil recovery lIDd

lIS aulhoriZllli.on for sto~ and retrieval of natul1ll gas and other hydrocari:lons. Carbon dioxide

i5 often II part oftbe fluids that are brought 10 the surface in 00f\/1C'Cli0n witlt con\'eIltionai oil or

1llI!um1 gB$ production openUom. It is. therefore, often a component ofthe acid psstream that..

in 50IDC casc:s. is injected for disposal - effectivdy -.ue:uering the eatbon dioxide component

of this stream. The sequesuatioll of carbon dioxide in this silUalion is incidental to the primary

activity, which is the disposal of acid gas. A distinction needs to be made in EPA's rules

between the incidental sequestering of carbon dioxide in an acid gas disposal and an

activity wiJox primary purpo!it is to -,UCSler earbon dioxide WJder the new ",oposal Class VI

luthoriution. ll'A strongly urges EPA to ensure that the status quo for existing operations

(l()lV;Iueted IDler Class II injection well IUthorizations is pnxected lIDd maintained Eliminatioo

or modifK:lltion ofthe CIlISlI II injection well program would have a X''el'e eoonomie imjlilct on

the oil and gas indusuy. TPA requests EPA to make an affirmative statement in the !inalrule

that the following CIlISlI II ~lls 1m: exempt from the applicability of Class VI wells

requirements, unless applicability is reqUCSled by the o~ or operator of the well: (I) those

CllISlI 11 w~lls that inject carbon dioxide and other fluids which are brought CO the 'urface in

connlXtion with oonventional oil or natural gas production operations; lUld (2) those Class 1I

wells that inject carbon dioxide and other fluids which are opt11ltcd in oonnc<:tion with an

enhanced oil or gas recovery field. This expTCSs excmption would elimilllltc any confusion

bct....'CCn the Class 11 and Vlwcll programs that may arise should EPA remain silent on this issue.

1. EPA should adopt II perlormllncc-bll!led regulltol')' ...heme rather than the

MTallored-General Provision" Ipproacb it h.. proposed.

Any regulatory approoch to tteologic sequestration must be bII!Ied on the roco~ition tllat

no two sites are alike. Because: this is so. it is crucial that the regulatory scbeme that is

ultimately implemented be ODe that is ftexible and pcrformance-ha.<;ed, TIlther than one that

imposes acros,s.tbt-board laIuiremenl$ that 1IIll)' be lIJlPffipriatt for one kind of site but

i\lllppropriat~ for another. The need for f1eJlibility is only inaeased by !be fact that there is still a

good deal co Ieam about Iarge-sWe plogic seq\JCSll'8llion. PmnaluR: imposilKln OfjlidCriplive

requirements oou1d damper !be developmcnt and future interest in these proje<u by companies

that mighl otherwise be int~ed in entering this new flcld. EPA 5houId IDe performance-t.scd

SUIIldards and sbouJ.d maintain flexibility in the creaIioo md impkmenWKln of rettulatory

requiremmts. in light of the variations in geologic formatioos that will be enc:ounltred from

project 10 project. Imposition of Mone-size.lits-all~ requirements wouJd be inapptopi.ue and

WO\lid unneeessarily hindcT full ~klpil.tnt ofseo1ogjc sequc:stnlUon technolog)'.

TPA believes that the best approIICh would be for states "'ith primac)' 10 oo-elop specifIC.

performance-based standards '-ed on the particular geologic chanocteristics md experience with

deep ~11 injection activities ptacnt in the respective states. Texas. in particular. has a breadth

and depth of experience in this area and our Texas regulatory body. the Texas Railroad

Commission. has the te:ehnica1 CXpc:r1ise and knowtodge to devr:1op criteria suiled 10 our SUitt.

Geologic sequestration can be an important tool in the llIItion's effort 10 reduce greenhouse gas

emissions, but onl), if its implementation is IlOI hindered by unnecessarily burdensome or
inflexible regulations. TPA recognizes that performance-based standards impose an increased

burden on regulators. but if geologic sequestration is to be widely utilized as a means to redUIX"

carbon dioxide emissions, then there really is no a1tema!ive.

The importance of protecting drinking water is obvious. and no one in the 011 and gas

industry is seeking to cut regulatory corners. "ITA is simply urging EPA to recognize both the

need for flexibility in the regulatory regime and the importance of fostering public confidence in

the safety of geologic sequestration technology.

3. EPA should not go beyond tbe provisions oftbe Safe Drinking Water Act (SDWA)

in tbe development of rules to support geologic sequestration of carbon dioxide.

As a word of caution, TPA urges EPA to limit its development of criteria for the safe

long term storage of carbon dioxide to its statutory authority under tbe SOWA. The statutory

authority under which EPA is proceeding in this rulemaking is limited to the SOWA. Any

anempt by EPA to propose eriteria that exceed the boundaries or authority ofibe SOWA would

be inappropriate. TPA recognizes that it is anticipated that this program will be a component of

any future climate change program that Congress may fashion in the future. As tempting as it

might be to establish criteria in this rule package that will complement a future caronn cap-andtrade or other regulatory program, we would urge EPA not to do so. Only after Congress

finalizes the slnicture of a climate change program should EPA begin development of those

complimentary provisions.

SPECIFIC COMMENTS

I. Tbe proposed finaudal assurance requirements span lin unrealistic lind

unnece$Sllrily lengthy period oftime.

The financial assurance requirements for corrective action, PQst-injection site care. and

site closure should be modified so as to avoid an unrealistic length oftime during which financial

arrangements must remain in place. "ITA believes that a realistic approach to this issue is

cmcial, because it is likely that imposition of unduly onerous financial assulWlce requiremcnts

would severely hinder developm.:nt and implem.mtation of geologic sequestration technology.

In no event should Class VI financial assurance requirements be more onerous than those

applicable to Class I wells, given that carbon dioxide is a common and genel'lllly harmless

substance, unlike the far more dangerous substances that can be associated with Class [ wells.

TPA urges the adoption ofsite-specific fmancial asSUl'llnce requirements, which would take into

account the differences from project to project as well as the declining risks that the project

would present over time For example, once the injected carbon dioxide plume has stabilized

over time. the amount of financialltsSurnnce required should be subject to reduclion as any risks

posed by that project will IlOt be as great as in the early years. The reduction in financial

assurance could be subject to a demonslration that dangers presented by a sequestration project

have diminished. In addition, if a site has been certified as closed, and the project presents no

danger to the public. then participants in the project should be released from any further

monitoring or frnancial assurance requirements. "ITA urges EPA to consider mechanisms such
as group ste....ardship anangemc:ulS or designaled managemmI entities for the post-(:\osurc:

,.noo.

2. Tile proposed posl-dos.re l'tIre period similarly _paM an UDIUlliuic IDd

.D~riIy~~by puiod oCti.n.

TPA di$agrtts v.ith the imposition ofl default SO-year post-injection site care period. A$

!ilaIed in the Pieced'ng eonunent, TPA urges the provision of flexible.. site-5peCific requimnmts

cooceming the knj!th of the post-injcc1ion silc CaR: period that coincide with the timeframe

established for financial asswartCe. A blanket SO-year period would unduly di5COUrage the use

of geologic sequestration technology and reduce the number of willing participants in this

progmm. Creation of a default period of SO yelll1l would discoUf3ic investment in geologic

sequestration technology. alld it might also removc the incentive to IQl:llte and develop storage

sites wi\Jllhe most favorable conditions. While EPA has provided a mechanism to reduce this

time frame on a case-by-case basis, the imposition of a default SO-year post-injection site care

period by itselfcould dcttT lTUIlIy otherwise-willing participants. Acoordingly, TPA rccommends

thai EPA provide thai the post-injection site care period be established on a case-by-casc basis as

a part ofthe ptrmilling ....occss.

The required kvel oftesting and monilOring should be determined on I site-b)-sitc basis.

Imposition of an across-tbc-boivd m:juirtment wouJd be inappropriate given the variations in

~Iogic fonnations.. and such a requiJeDIem would inhibit the developltlcnt and usc of g«llogic

sequestration with lillie:: 01" 110 ro=spooding cnvironmeotaJ bmefit in oenain cases.. Regulatory

bodies and opcraIOr3 should be free to Illilof monitoring techniques to the specific conditions at

each particular site, upon a determination thal the techniques would produce reliablc data. In

addition. tbere should be no blanket requiremcnt for the use of tracers to ddect leaks. Such a

requirement would send an CliODOOUS siinal to the public concerning the risks involved in

geologic sequestration. Geologic sequestration will not develop as a helpful tool in reducinll

greenhouse gltS emissions if the wronll signals are sent to the public. The utility of tracers for

monitorinll carbon dioxide leaks is uncertain in any event, and the USOl of tracers may create

health or safety issues for workers and for the public.

TPA d~with the proposed requirement of oo...n-hole automatic sbut-olf devices.

This requinmenl is not imposed upon wells in other classc:s and is no wby sucb a

requirancnt sboold be placed. Oft an across thI:-board basis, upon Class VI ..~lls. Such a

requiremcm would impose an \II_lee( 'ry cxpense ill many CllSICS. At most, such a requirement

shoWd only be imposed on. sitc-spociflC. case-Oy-<:ISC t.sis.

S. TIle arbe. dioxide IIft:UD is a eo.lllodity .ot I wlSl~ and Ibould be ~ulated II

slKb.
F.PA shouJd make dear !hal. carbon dioxide injectak is no( being or regulated

as a ....ue or a pollll1aJll, but rather as a commodity. The scquc:steml carbon dioxide is expected

to generate a credit in a future carbon tt'edit scheme. At that poiDl !be ICI of sequestering tbc:

carbon dioxide: ....ill genrt811: an emission credit that can be sold in lhe open 1TIlIRel:.

Accordingly, TPA urges EPA to mnain DC'utralat this point in time in clwacterizing lhe carbon

dioxide sImlm as a waste or a pollutant in any ofits regulatory programs. Those kinds of labels

would saddle this program with the liability schemes imposed by RCRA or CERCLA and would

be severely detrimental to the development and use of geologie sequestl'lttion teo:.:hnology, It is

highly unlikely that industry will commit the substantial capital required for geologic

sequestnltion projeo:.:ts unless and Wltil the potential for liability is clearly defined and undcrstood.

Such financial CQrllJ1lilmellt is unlikely to be made if participants run lhe risk of iocurring open·

ended and ruinous liability WIder RCRA and CERCLA. In this KglII'd. Class VI pennits should

be ....Titten as broadly as possible. so as to maximize protc:ctions that may be provided by

federally pcrm.iued re1eage exemptions.

6. laddeatal1ulIte stmms in tbe earboll diodde urnm should oot cause the stmm

to be ehu1lderiud as a lIazudous waste.r llaurdolU subuan«.

As EPA has pointed OUI. the carbon dioxide sImlm may have pollutants in it that (:()tI1d

cause the waste stream 10 be classified as a waste. For example, the carbon dioxide

stream captured from a powcr plant may ioclude cmillsions of mereury, a hazardoussubstaoce.

A carbon dioxide stream captured from It llll$ processing pll\llt may have emissions of nitrous

oxides or hydrogcn sulfides. The iocidcntal pre!IL'TlCC ofthese waste streams in a earbon dioxide

stream should not cause the entire carbon dioxide stream to be e1lt5Sified II!l a ha7..vdous waste or

a wastc. The proposed regulations do noc specify contenl or constiruent concentl'lttion

fl:quirenv:nlS, they merely state that ~(Ilhis subpart does not apply 10 any carbon dioxide Streml

that meets lhe definition oh hazardous ....ute WIder 40 CFR pan 261.- Proposed § 146.8I(d).

TPA urJCS EPA to eilablish a conl8tt pel"CC'lllRge or OODStituerJl COIiIXutnl1ioo of a pollutant in

!he earboa dioxide before lhe stteam is declared a hvsrdous ....1ISIC. or some other

methodoIotD' that would promote the goals ofthis JlrOInm withoul oomprornising cuvi.oounental

proleCtion. Tlle COS! of removing the offendina oonslituerJts or pollutants could defeat the

economic viability of the <:arbon sequcstnllion project. generlllc addilional detrimental air

emiuions through the removal process and in the end be counter-productive as the best longterm disposal option for the pollulWlt may be 10 sequcstCf il in a deep well. In short. such

specifications might restrict the amount or kinds of greenhouse gas Ouids that could be stored

through geologic sequestration I."chnology and may dcfeatthe prollfllrrl in its entirely,

7. C......deriuttoo of a K'COodary containment zone should not be left to tbe

d~retioll oflbe Dirttlol".

The proposed regulations provide !hat at the Director's discretion.. be or she shall fl:qWre

o....ners or opera!on of Class VI wells to identify and cIllUacterizc srooodary containment or

CQnfuw:ment zones. Rather than !Wing this provision as a requittment to be imposed upon an

applicant at the discretion ofthe Director, TPA suaaests that EPA esIabI.isb this provision as an

additional denllHlSIlation 10 be made by an applicant. io !be evcut that • secondary confinemenl

,.one is prdenl at the sit<:. "[he cxisleocc of a secondary confining zone would make the site
more attractiv~ foc permining at1d should be treated as an incentive to make the permitting

process progress more smoot.hJy and $WiNy. A secondary oontainment lOne is eenainly oot

needed to ensure safe geologic $equesuation. lI.!ingle OOIllllinment l:OIlC is all that is needed.

Accordingly. ifa secondary containment lOne does exist at the site.. then the applicant should be

IWvKled the opportunity 10 demonstl'at~ that il does exm and to receive preferential treatmetlt in

the pennitting ptOlXSS as a resu.lL

8. Imposition of ~rTOSion-resistantmaterillis is too prescriptin.

Requirements ......wxlning use ofpanicular rnateriab should be imposed on a case-by-c:llSC

basi!. for example. the regulalions sbouId IJO( requ~ that all projects use COfl'OSkln-resistam

material$. isolation and corrosion prnention i! the ~t of the proper pa.cement of

cemenL I1Itber than the type of ccmmI used. Any requirement related 10 the use of corrosionresiSIMt materials should be made on a .site-by-!ile basi$. Imposition of inOexible.. across-theboard materiab requiremenl$ would unduly hinder development aod use of geologic

sequestration te<:hnology. given that the use of conventional materials will adequately ensure

project integrity in many cases.

9. CasinK material rfiluirtments ...e similarly prucriptive.

Requirements concerning use of particular casing materials should be based on the

planned operating life of the injection program, rnther than the life of the stornlle program.

Long·term exposure ofthe casing materials, during storage. can be dealt with throuj,\h plugging if

necessary.

10. Requiring that the injfCIioD wne !x !xlo... the Iowermon USDW is onerous ud

unjuSlil'"ll'd.

TPA disagrees "'1th the pmposallhat geologic !lCQue:stmtion be limited in all ClIllCS to an

injeclion zone that occurs below the \owermost WJdcrground source of drinking water

(\JSDW"). Rather, a peOOI'UWlCe-based lIpplt*h should be taken. in wbich the focus i! on the

QOIlwnment qualities of the inject.ion inlel'Vlll and 011 the o\'Cnl1 geological environment, 001

simply on ",1Jdber the reservoir is above or below the lowermost USDW$. TPA would DOle that

carbon dKJxide bas bttn injected above the lowermost USDWs for decades without incidem in

connect.ioo with mhanc:cd oil and gas nlCOvcry dToru in Texas. Imposilion of an inflexibk

requirement that injection oo1y occur below the kMemlOSl USDW would unduly hinder the use

of geologic sequestration technology, and it would be partieularty inappropriate in imtllnl::es

where an inje<;tion site WlIs sitlWed 1lboYl: a USDW but there WllS a great distance bo;:t..CCil the

injection site and the USDW and the characteristics ofthe intervening space: Pf':,'ented migration

betvl;~en the site lU1d the USDW. EPA's focus should be on the particular physical cl\anlo;leristics

that arc JIlcsented. including distance and physical characteristics of the intervening space such

as discusstd. above. as well as the OOIltainmcnl qualities of the injection site being proposed. A

site-specific approach .....ould increa.'le the use at1d thus the effectiveness of geologic 5equeslIlltion

technology.
II. GnllldfalllfriDl!: af."t'U t'Omtrudioa .lalld.,-ds for ClUJ II aDd a-. V ..-dh .hould

bot' pl'O\'ided ."itbolll ~DdilioD.

EPA proposes 10 grandfathc:r dr ",-ell conslrUction standards for a Class II and a Class V

",,~11 tbal is converted to a Class VI ~II and rrque:sl$ C(lllllllelIlS on how Ibis proposal may alTn:l

oomplianct' with dr proposed well (;OllSlruetion slandards for Class VI wells. TPA believes that

!he conslruction standards for an existing Class II or V well thaI is converted to a Class VI well

should be accepled by EPA as having met the CIlllIS VI well construction requirements. The

meaning of Mgmndfathering" an environmental requirement is just lhat: !he requirements in

place at the time continue to apply. If this were not the case, a viable sequestration project may

not occur as development ofa new well may be cost prohibitive.

TPA rewgnizes that Mkntificatioo of Ion¥ lenll. liability is beyond this rulemaking.

However, TPA believe;; it is imjlONnt to note that clarification of wbiclt partie3 would be

~ible for uninteoded mignllion 01" slmilar problems after I ~11 bIId t-n clost'd is vitally

important 10 the long lenD suettss of this progntm. Such an issue sbouId be addressed by

legislation at eithc:r the state or fedcrallevel.

In cl~ing. we wish 10 expr1:ss again that TPA appreciates the opponunity to provide

these comments on this rulemaking for a program lila! will be vitally important to our national

policies 10 address climate change.
Letter ID: 0143 

Commenter: Patrick Nugent 

Organization: Texas Pipeline Association (TPA) 

Letter ID: 0143 Comment ID: 23123 Letter Lines: 53 to 81 

Comment Code: 2046 1.5.2.3 Continuing to classify CO2 injection for EOR/EGR as Class II/ 

dividing line between Class II and Class VI (seeking comment) 

Comment: 1. Development of a Class VI injection well program should not impair or 

any way modify existing authorizations for Class injection wells. 

As mentioned above, the oil and gas industry relies upon the authorization 

provided by the Class H injection well program for the disposal of acid or sour 

gas, enhanced oil recovery and as authorization for storage and retrieval of 

natural gas and other hydrocarbons. Carbon dioxide is often a part of the fluids 

that are brought to the surface in connection with conventional oil or natural 

gas production operations. It is, therefore, often a component of the acid gas 

stream that, in some cases, is injected for disposal -- effectively sequestering 

the carbon dioxide component of this stream. The sequestration of carbon dioxide 

in this situation is incidental to the primary activity, which is the disposal 

of acid gas. A distinction needs to be made in EPA's rules between the 

incidental sequestering of carbon dioxide in an acid gas disposal operation and 

an activity whose primary purpose is to sequester carbon dioxide under the new 

proposed Class VI authorization. TPA strongly urges EPA to ensure that the 

status quo for existing operations conducted under Class II injection well 

authorizations is protected and maintained. Elimination or modification of the 

Class II injection well program would have a severe economic impact on the oil 

and gas industry. TPA requests EPA to make an affirmative statement in the final 

rule that the following Class II wells are exempt from the applicability of 

Class VI wells requirements, unless applicability is requested by the owner or 

operator of the well: (1) those Class II wells that inject carbon dioxide and 

other fluids which are brought to the surface in connection with conventional 

oil or natural gas production operations; and (2) those Class II wells that 

inject carbon dioxide and other fluids which are operated in connection with an 

enhanced oil or gas recovery field. This express exemption would eliminate any 

confusion between the Class II and VI well programs that may arise should EPA 

remain silent on this issue. 

Individual Response: EPA agrees that injection of CO2 for the primary purpose of enhancing 

oil and gas recovery should remain under the Class II Program. EPA recognizes that the oil and 

gas industry has decades of experience injecting CO2 for the purpose of EOR, and that sites used 

for ER may be suitable for GS and may be among the first GS sites. EPA also recognizes that a 

by-product of EOR activities is that a certain percentage of the CO2 is trapped in the receiving 

formation. 

1
The Agency believes that the nature and risks associated with CO2 injection for the primary 

purpose of long term storage poses different risks than injection for the primary purpose of ER, 

and therefore has developed new Class VI regulations to address these unique risks. For 

example, the volume of CO2 anticipated to be injected for long term storage is significantly 

greater than for EOR operations. Reservoir pressure conditions will also be different, with Class 

VI injection operations involving large volumes of CO2 and likely having higher pressures 

within their storage formations than Class II EOR projects. 

EPA clarifies that the GS rule does not “exempt” any specific activity from Class VI 

requirements, but rather defines the tailored requirements that are necessary for the long-term 

storage of CO2 in order to protect USDWs. The final Class VI regulations require that any owner 

or operator injecting CO2 for the primary purpose of long term storage obtain a Class VI permit 

with some special consideration for the fact that they are transitioning from a well not originally 

designed to meet Class VI requirements. The Director has the authority to determine at what 

point a Class VI permit is required for those projects that are transitioning from the primary 

purpose of EOR to long term storage of CO2. The final regulation provides a set of technical 

factors for the Director to evaluate in making this determination, at §144.19. EPA believes that 

this approach provides sufficient protection of USDWs when there is an increased risk to 

USDWs as compared to traditional Class II operations while allowing for site-specific flexibility. 

EPA is developing guidance on transitioning permits from Class II to Class VI. The guidance 

will assist Directors in determining whether an injection project should be transitioned from 

Class II where the primary purpose is oil and gas production to Class VI where the primary 

purpose is long-term storage of large volumes of CO2. The guidance describes the methods 

available for the Director to use in order to determine changes in risk to USDWs from projects, 

and how the Director may determine whether a project should be regulated within the Class II or 

Class VI UIC program. This guidance will be available on EPA’s website at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. For more information, please 

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

Letter ID: 0143 Comment ID: 23124 Letter Lines: 83 to 117 

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

Comment: 2. EPA should adopt a performance-based regulatory scheme rather than the 

"Tailored-General Provision" approach it has proposed. Any regulatory approach 

to geologic sequestration must be based on the recognition that no two sites are 

alike. Because this is so, it is crucial that the regulatory scheme that is 

ultimately implemented be one that is flexible and performance-based, rather 

than one that imposes across-the-board requirements that may be appropriate for 

one kind of site but inappropriate for another. The need for flexibility is only 

increased by the fact that there is still a good deal to learn about large-scale 

geologic sequestration. Premature imposition of prescriptive requirements could 

damper the development and future interest in these projects by companies that 

might otherwise be interested in entering this new field. EPA should use 

2
performance-based standards and should maintain flexibility in the creation and 

implementation of regulatory requirements, in light of the variations in 

geologic formations that will be encountered from project to project. Imposition 

of "one-size-fits-all" requirements would be inappropriate and would 

unnecessarily hinder full development of geologic sequestration technology. 

TPA believes that the best approach would be for states with primacy to develop 

specific, performance-based standards based on the particular geologic 

characteristics and experience with deep well injection activities present in 

the respective states. Texas, in particular, has a breadth and depth of 

experience in this area and our Texas regulatory body, the Texas Railroad 

Commission, has the technical expertise and knowledge to develop criteria suited 

to our state. Geologic sequestration can be an important tool in the nation's 

effort to reduce greenhouse gas emissions, but only if its implementation is not 

hindered by unnecessarily burdensome or inflexible regulations. TPA recognizes 

that performance-based standards impose an increased burden on regulators, but 

if geologic sequestration is to be widely utilized as a means to reduce carbon 

dioxide emissions, then there really is no alternative. 

The importance of protecting drinking water is obvious, and no one in the oil 

and gas industry is seeking to cut regulatory corners. TPA is simply urging EPA 

to recognize both the need for flexibility in the regulatory regime and the 

importance of fostering public confidence in the safety of geologic 

sequestration technology. 

Individual Response: The Agency believes that the Class VI requirements balance site-specific 

flexibility with USDW protection. Rather than setting performance or technology-based 

standards for GS projects, EPA is adopting a flexible approach, where operators of GS projects 

would develop and implement site-specific plans for delineating the AoR, testing and monitoring 

the site, performing corrective action, and post-injection site care. EPA believes that the plans—

which would be reviewed and approved by the Director and periodically updated throughout the 

life of the project—promote an ongoing dialogue between the operator and the Director that will 

encourage use of the most appropriate technologies for a particular project. 

In response to the comment that States with primacy be able to develop “performance-based 

standards,” the Agency clarifies that States, Tribes, and Territories can develop requirements for 

Class VI and submit primacy applications (under Section 1422 of the SDWA) for review and 

approval by EPA as long as the requirements are as stringent as or more stringent than the 

Federal minimum requirements. 

Letter ID: 0143 Comment ID: 23125 Letter Lines: 113 to 117 

Comment Code: 1680 1.3.8 Don't overstate risk, don't stigmatize CO2 

Comment: The importance of protecting drinking water is obvious, and no one in the oil 

and gas industry is seeking to cut regulatory corners. TPA is simply urging EPA 

3
to recognize both the need for flexibility in the regulatory regime and the 

importance of fostering public confidence in the safety of geologic 

sequestration technology. 

Individual Response: EPA recognizes that injecting large volumes of CO2 for GS poses unique 

challenges that, if not properly managed, could endanger drinking water sources and have other 

adverse impacts. However, with proper site selection, the final, tailored, Class VI requirements 

address the large volumes of CO2 injected, its buoyancy, potential corrosivity in the presence of 

water, and potential impurities in the CO2 stream. In addition, EPA expects the tailored 

permitting, siting, construction, operation, monitoring, and post-injection site care requirements 

in the GS rule to prevent leakage from injection formations and protect USDWs. Thus, EPA 

believes that the GS rule will foster public confidence in the safety of GS. 

EPA agrees that flexibility is important. EPA notes that, under the final rule, many of the permit 

requirements will be established through site-specific plans developed by the owner or operator 

and approved by the Director. Consequently, EPA anticipates that owners or operators will 

consult with the Director as they develop, implement, and update these plans. The final GS 

regulation gives the Director discretion to set permit criteria that are appropriate to site-specific 

conditions. The regulation provides flexibility to select appropriate sites and target formations 

(under §146.82), well construction specifics (under §146.86), and testing and monitoring regimes 

(under §146.90), provided the owner or operator can demonstrate that the injection and storage 

will not endanger USDWs and that minimum requirements for the site are met. 

In addition, the final rule affords the Director flexibility to approve alternatives to the 

requirements in some cases. For example, the Director may in certain situations modify the 

length of the post-injection site care period, allow the use of alternate methods for mechanical 

integrity testing (if approved by EPA), and waive the requirement that wells be designed to inject 

below the lowermost USDW. 

Letter ID: 0143 Comment ID: 23126 Letter Lines: 119 to 132 

Comment Code: 1400 1.2 Comments on EPA's Authority to Regulate Injection of CO2 

Comment: 3. EPA should not go beyond the provisions of the Safe Drinking Water Act 

(SDWA) in the development of rules to support geologic sequestration of carbon 

dioxide. As a word of caution, TPA urges EPA to limit its development of 

criteria for the safe long term storage of carbon dioxide to its statutory 

authority under the SDWA. The statutory authority under which EPA is proceeding 

in this rulemaking is limited to the SDWA. Any attempt by EPA to propose 

criteria that exceed the boundaries or authority of the SDWA would be 

inappropriate. TPA recognizes that it is anticipated that this program will be a 

component of any future climate change program that Congress may fashion in the 

future. As tempting as it might be to establish criteria in this rule package 

that will complement a future carbon cap-andtrade or other regulatory program, 

we would urge EPA not to do so. Only after Congress finalizes the structure of a 

climate change program should EPA begin development of those complimentary 

4
provisions. 

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

the need for regulatory clarity to ensure that USDWs are protected from endangerment. In 

developing the final GS rule, the Office of Water coordinated with other Agency program offices 

and across federal agencies (e.g., with the Department of Energy; United States Geological 

Survey; Bureau of Ocean Energy Management, Regulation, and Enforcement, formerly the 

Minerals Management Service; Bureau of Land Management). The Agency continues to evaluate 

areas of potential applicability of other Federal environmental statutes including, but not limited 

to: the Clean Air Act; the Resource Conservation and Recovery Act; the Comprehensive 

Environmental Response, Compensation, and Liability Act; and the Marine Protection, Research 

and Sanctuaries Act to various aspects of GS and CCS. The Agency will continue to coordinate 

on GS and CCS related issues to minimize redundancy and maximize efficiencies for owners or 

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

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

the final GS rule. 

EPA adds that regulating carbon cap and trade is outside of the UIC program's authority under 

SDWA. 

Letter ID: 0143 Comment ID: 23127 Letter Lines: 136 to 146 

Comment Code: 5430 2.9.1 Comments on proposed financial responsibility requirements (40 

CFR 146.85) 

Comment: 1. The proposed financial assurance requirements span an unrealistic and 

unnecessarily lengthy period of time. The financial assurance requirements for 

corrective action, post-injection site care, and site closure should be modified 

so as to avoid an unrealistic length of time during which financial arrangements 

must remain in place. TPA believes that a realistic approach to this issue is 

crucial, because it is likely that imposition of unduly onerous financial 

assurance requirements would severely hinder development and implementation of 

geologic sequestration technology. In no event should Class VI financial 

assurance requirements be more onerous than those applicable to Class I wells, 

given that carbon dioxide is a common and generally harmless substance, unlike 

the far more dangerous substances that can be associated with Class I wells. TPA 

Individual Response: EPA disagrees that the requirements for financial responsibility are overly 

stringent. The goal of financial responsibility is to ensure that resources are available to prevent 

the endangerment of USDWs from improper plugging, remediation, and management of wells in 

the event that the owner or operator experiences financial difficulties throughout the life of the 

project. 

EPA believes that minimum financial responsibility requirements are necessary to prevent 

endangerment of USDWs by to holding well owners or operators accountable for the safe 

operation and proper closure of the Class VI wells while avoiding expense and risk to the public. 

5
EPA adds that the purpose of the GS rule is not to encourage the use of GS; rather, the purpose 

of the GS rule is to ensure that, where GS is deployed, it is conducted in a manner that protects 

USDWs from endangerment. 

See the final rule and preamble for further discussion of EPA's final approach to financial 

responsibility. 

Additionally, EPA is developing guidance (available on EPA's website at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm) that describes the types of 

financial instruments that owners or operators can use to meet financial responsibility 

requirements for GS wells. 

Letter ID: 0143 Comment ID: 23128 Letter Lines: 146 to 154 

Comment Code: 5430 2.9.1 Comments on proposed financial responsibility requirements (40 

CFR 146.85) 

Comment: the far more dangerous substances that can be associated with Class I wells. TPA 

urges the adoption of site-specific financial assurance requirements, which 

would take into account the differences from project to project as well as the 

declining risks that the project would present over time For example, once the 

injected carbon dioxide plume has stabilized over time, the amount of financial 

assurance required should be subject to reduction as any risks posed by that 

project will not be as great as in the early years. The reduction in financial 

assurance could be subject to a demonstration that dangers presented by a 

sequestration project have diminished. In addition, if a site has been certified 

Individual Response: EPA agrees that it is appropriate to allow a flexible approach for financial 

responsibility. Under the final GS rule owners or operators may choose from a variety of 

financial instruments to demonstrate that they meeting the financial responsibility provisions, 

provided the Director determines that the owner or operator's proposed financial responsibility 

demonstration is adequate to protect USDWs from endangerment, which for example could 

mean to pay for each activity for which financial responsibility must be demonstrated, including 

corrective action on wells in the AoR, injection well plugging, PISC and site closure, and 

emergency and remedial response. 

The cost of securing financial responsibility instruments will be based on whether or not a third 

party financial institution is used and the agreement between the financial institution and the 

owner or operator. EPA expects that some third party providers, such as insurers, will take risk 

into account when determining the cost of coverage. However, cost is expected to depend 

heavily on the estimated cost of covered activities as well as certain site-specific factors. 

In order to assist owners or operators and financial institutions in achieving accurate cost 

estimates, EPA is developing guidance (available on EPA's website at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm) to help owners or operators, 

permitting authorities, and third parties choose and evaluate appropriate financial methods. EPA 

6
plans to include a discussion of how to estimate costs, including how to adjust cost estimates for 

inflation, in its guidance on meeting financial responsibility requirements for GS wells. 

Letter ID: 0143 Comment ID: 23129 Letter Lines: 154 to 157 

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

Comment: sequestration project have diminished. In addition, if a site has been certified 

as closed, and the project presents no danger to the public, then participants 

in the project should be released from any further monitoring or financial 

assurance requirements. TPA urges EPA to consider mechanisms such as group 

Individual Response: Under the final GS rule, once an owner or operator has met all regulatory 

requirements under Part 146 for Class VI wells and the Director has approved site closure 

pursuant to requirements at §146.93, the owner or operator will generally no longer be subject to 

enforcement for regulatory noncompliance. Furthermore, 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 certain circumstances. For example, an owner or operator may be 

held liable for regulatory noncompliance even after site closure was approved if the Director 

relied on erroneous information (e.g., erroneous modeling data) provided by the owner or 

operator when approving site closure. 

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

subject to a §1431 response order even after proper site closure is approved under §146.93. 

Under §1431 the Administrator may require an owner 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 present an imminent and substantial endangerment 

to the health of persons, and the appropriate State and local authorities have not acted to protect 

the health of such persons. The action may include issuing administrative orders or commencing 

a civil action for appropriate relief against the owner 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 operator may remain liable under tort and other 

remedies, or under other federal statutes including, but not limited to, Clean Air Act, 42 U.S.C. 

§§ 7401-7671; CERCLA, 42 U.S.C. § 9601-9675; and RCRA, 42 U.S.C. § 6901-6992. EPA 

does not have authority to transfer SDWA or other legal liability for Class VI wells to the State 

or federal government or a third-party fund. See the final rule preamble for further discussion of 

EPA's final approach. 

Letter ID: 0143 Comment ID: 23130 Letter Lines: 157 to 159 

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

7
Comment: assurance requirements. TPA urges EPA to consider mechanisms such as group 

stewardship arrangements or designated management entities for the post-closure 

period. 

Individual Response: Under the final GS rule, once an owner or operator has met all regulatory 

requirements under Part 146 for Class VI wells and the Director has approved site closure 

pursuant to requirements at §146.93, the owner or operator will generally no longer be subject to 

enforcement for regulatory noncompliance. Furthermore, 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 certain circumstances. For example, an owner or operator may be 

held liable for regulatory noncompliance even after site closure was approved if the Director 

relied on erroneous information (e.g., erroneous modeling data) provided by the owner or 

operator when approving site closure. 

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

subject to a §1431 response order even after proper site closure is approved under §146.93. 

Under §1431 the Administrator may require an owner 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 present an imminent and substantial endangerment 

to the health of persons, and the appropriate State and local authorities have not acted to protect 

the health of such persons. The action may include issuing administrative orders or commencing 

a civil action for appropriate relief against the owner 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 operator may remain liable under tort and other 

remedies, or under other federal statutes including, but not limited to, Clean Air Act, 42 U.S.C. 

§§ 7401-7671; CERCLA, 42 U.S.C. § 9601-9675; and RCRA, 42 U.S.C. § 6901-6992. Please 

note that EPA does not have authority to transfer SDWA or other legal liability for Class VI 

wells to the State or federal government or a third-party fund. See the final rule preamble for 

further discussion of EPA's final approach. 

EPA notes that under SDWA, EPA has the general authority to set financial responsibility 

requirements for injection well owners or operators to ensure that adequate resources are 

available to protect USDWs throughout the life of the GS project. However, this authority does 

not extend to allowing the Agency to create a financial instrument with EPA as the trustee. 

Furthermore, EPA does not have authority in the SDWA to create a trust fund. The Agency 

clarifies that the trust funds that are addressed as financial responsibility instruments through the 

GS rule are set up by individual owners or operators and are different from a national-level trust 

described by the commenters that would cover large numbers of GS projects. 

Letter ID: 0143 Comment ID: 23131 Letter Lines: 161 to 163 

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

8
Comment: 2. The proposed post-closure care period similarly spans an unrealistic and 

unnecessarily lengthy period of time. TPA disagrees with the imposition of a 

default 50-year post-injection site care period. As stated in the preceding 

Individual Response: EPA disagrees that a post-injection site care timeframe of 50 years is 

excessive for most Class VI wells. EPA proposed a default post-injection site care timeframe of 

50 years based on a review of research studies, industry reports, and existing environmental 

programs. This analysis was included in an EPA-prepared background document that is available 

in the federal docket, titled "Computational Modeling of Underground Injection of Carbon 

Dioxide for Determination of Area-of-Review and Potential Risk to Underground Sources of 

Drinking Water." EPA assessed various default timeframes based on additional review of 

research studies and evaluation of public comments. While numerous commenters suggested that 

EPA shorten the monitoring timeframe, none of the commenters provided sufficient data or other 

evidence to warrant a change in the proposed timeframe. While the 10- or 30-year timeframe 

suggested by some of these commenters may be within the timeframe suggested in some studies, 

EPA believes that the potential risks of endangering USDWs will likely not decline within these 

timeframes and available data, including data submitted by commenters, do not support a 

different default timeframe. 

However, EPA recognizes that there may be sites where the 50 year post injection site care 

timeframe may be either not appropriate or more burdensome than necessary based on sitespecific conditions. For this reason, the GS rule offers owners or operators flexibility regarding 

the duration of the PISC timeframe by: (1) allowing the Director discretion to shorten or 

lengthen the PISC timeframe during the post-injection period based on site-specific data, 

pursuant to requirements at §146.93(b); or (2) affording the Director discretion to allow a Class 

VI well owner or operator to demonstrate, during the permitting process based on substantial 

data, that an alternative PISC timeframe may be appropriate if it ensures non-endangerment of 

USDWs pursuant to requirements at §146.93(c). 

EPA believes that a default post-injection site care timeframe of 50 years, with flexibility to 

adjust the timeframe for a limited number of GS projects during the permitting process where 

substantial data exists to demonstrate that an alternative timeframe would be protective of 

USDWs, or based on data collected during the PISC period, is appropriate to address the range of 

sites where GS is anticipated to occur, to accommodate site-specific circumstances and various 

geologic conditions, and addresses commenters’ concerns, while ensuring USDW protection. 

Both approaches will utilize site-specific data, and be based on pressure monitoring and USDW 

impacts, as the commenter suggests. 

Letter ID: 0143 Comment ID: 23132 Letter Lines: 163 to 166 

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

Comment: default 50-year post-injection site care period. As stated in the preceding 

comment, TPA urges the provision of flexible, site-specific requirements 

concerning the length of the post-injection site care period that coincide with 

the timeframe established for financial assurance. A blanket 50-year period 

9
Individual Response: As stated above, EPA disagrees that a post-injection site care timeframe 

of 50 years is excessive for most Class VI wells. However, EPA recognizes that there may be 

sites where the 50 year post injection site care timeframe may be either not appropriate or more 

burdensome than necessary based on site-specific conditions. For this reason, the GS rule offers 

owners or operators flexibility regarding the duration of the PISC timeframe by: (1) allowing the 

Director discretion to shorten or lengthen the PISC timeframe during the post-injection period 

based on site-specific data, pursuant to requirements at §146.93(b); or (2) affording the Director 

discretion to allow a Class VI well owner or operator to demonstrate, during the permitting 

process based on substantial data, that an alternative PISC timeframe may be appropriate if it 

ensures non-endangerment of USDWs pursuant to requirements at §146.93(c). 

EPA clarifies that owners or operators will need to demonstrate and maintain financial 

responsibility throughout the post-injection site care period, as required at 146.85. EPA 

recognizes that there are challenges associated with ensuring funding for activities that will occur 

far in the future. However, the Agency believes that in order to protect USDWs from 

endangerment under the SDWA operators must demonstrate under §146.85 that financial 

resources are available to plug the injection well and provide post-injection site care at the point 

in time that the first CO2 is injected. 

Letter ID: 0143 Comment ID: 23133 Letter Lines: 166 to 174 

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

Comment: the timeframe established for financial assurance. A blanket 50-year period 

would unduly discourage the use of geologic sequestration technology and reduce 

the number of willing participants in this program. Creation of a default period 

of 50 years would discourage investment in geologic sequestration technology, 

and it might also remove the incentive to locate and develop storage sites with 

the most favorable conditions. While EPA has provided a mechanism to reduce this 

time frame on a case-by-case basis, the imposition of a default 50-year postinjection site care period by itself could deter many otherwise-willing 

participants. Accordingly, TPA recommends that EPA provide that the postIndividual Response: EPA recognizes that there are challenges associated with assuring funding 

for activities that will occur far in the future. However, the Agency believes that operators must 

demonstrate that financial resources are available to plug the injection well and provide postinjection care at the point in time that the first CO2 is injected. EPA is developing guidance on 

financial responsibility to assist owners or operators in evaluating the requirements of §146.85 

and to assist Directors in evaluating financial responsibility demonstrations. The guidance 

describes the types of financial mechanisms that operators may choose to use when evaluating 

the financial responsibility requirements for GS wells and it will also include a section on how to 

estimate costs to support accurate financial responsibility demonstrations. The guidance will be 

available at http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

EPA adds that the purpose of the GS rule is not to incentivize the use of GS; rather, the purpose 

of the GS rule is to ensure that, where GS is deployed, it is conducted in a manner that protects 

10
USDWs from endangerment. 

Letter ID: 0143 Comment ID: 23134 Letter Lines: 174 to 176 

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

Comment: participants. Accordingly, TPA recommends that EPA provide that the postinjection site care period be established on a case-by-case basis as a part of 

the permitting process. 

Individual Response: EPA agrees that there will be circumstances where it can be demonstrated 

in less than 50 years that the plume and pressure front no longer pose a risk of endangerment to 

USDWs. For this reason, the GS rule offers owners or operators flexibility regarding the duration 

of the PISC timeframe by: (1) allowing the Director discretion to shorten or lengthen the PISC 

timeframe during the post-injection period based on site-specific data, pursuant to requirements 

at §146.93(b); or (2) affording the Director discretion to allow a Class VI well owner or operator 

to demonstrate, during the permitting process based on substantial data, that an alternative PISC 

timeframe may be appropriate if it ensures non-endangerment of USDWs pursuant to 

requirements at §146.93(c). 

EPA believes however, that to ensure USDW protection from endangerment, a default timeframe 

for post-injection site care will be necessary in most cases. The default 50 year post-injection site 

care timeframe represents a reasonable and protective monitoring period based on a review of 

research studies, industry reports, and existing environmental programs, and evaluation of public 

comments. 

EPA believes that a default post-injection site care timeframe of 50 years, with flexibility to 

adjust the timeframe for a limited number of GS projects during the permitting process where 

substantial data exists to demonstrate that an alternative timeframe would be protective of 

USDWs, or based on data collected during the PISC period, is appropriate to address the range of 

sites where GS is anticipated to occur, to accommodate site-specific circumstances and various 

geologic conditions, and addresses commenters’ concerns, while ensuring USDW protection. 

Both approaches will utilize site-specific data, and be based on pressure monitoring and USDW 

impacts. 

EPA is developing guidance to assist owners or operators in evaluating well plugging, postinjection site care, and site closure requirements of §146.92 and §146.93. Additionally, the 

guidance will assist Directors in evaluating proposed well plugging plans and post-injection site 

care and site closure plans under §146.92 and §146.93. The guidance describes recommended 

approaches for how an owner or operator could plug injection and monitoring wells; demonstrate 

the appropriateness of an alternative post-injection site care time frame; perform post-injection 

monitoring; demonstrate non endangerment; and perform site closure activities. The guidance 

will be available at http://www.epa.gov/safewater/wells_sequestration.html. 

11
Letter ID: 0143 Comment ID: 23135 Letter Lines: 178 to 186 

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

CFR 146.90) 

Comment: 3. One-size-fits-all testing and monitoring requirements should not be 

established. The required level of testing and monitoring should be determined 

on a site-by-site basis. Imposition of an across-the-board requirement would be 

inappropriate given the variations in geologic formations, and such a 

requirement would inhibit the development and use of geologic sequestration with 

little or no corresponding environmental benefit in certain cases. Regulatory 

bodies and operators should be free to tailor monitoring techniques to the 

specific conditions at each particular site, upon a determination that the 

techniques would produce reliable data. In addition. there should be no blanket 

Individual Response: EPA agrees with commenters and believes that flexibility is important in 

developing and implementing a monitoring plan that is appropriately tailored for a specific GS 

site. The purpose of the requirement at §146.90 to develop site-specific testing and monitoring 

plans is to ensure that the monitoring performed at a site is appropriate for site operational 

conditions and the geologic setting. EPA believes that this is the best approach for addressing 

potential risks at GS sites. These flexible provisions in the monitoring requirements for Class VI 

wells enable the owner or operator to tailor monitoring programs to the specific needs of each 

project in consultation with the Director. 

The final regulation provides for flexibility in: 1) methodologies used to collect these data, 2) the 

spatial resolution at which the data should be collected, and 3) how often the data should be 

collected. The number and placement of monitoring wells will be based on site-specific 

information such as the calculated AoR, injection rate and volume, site geology, baseline data, 

and the presence of artificial penetrations within the AoR. In some instances, there may be a 

limited number of options for complying with EPA's minimum requirements. For example, 

monitoring for geochemical changes will require use of monitoring wells and collection of 

groundwater samples for chemical analysis. Many options currently exist for complying with 

other requirements, such as tracking the position of the plume and pressure front within the 

injection zone. 

Flexibility is also provided regarding how to monitor for the specific data required by the final 

rule. The testing and monitoring plan is developed by the owner or operator 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, including proposed monitoring plans. The guidance describes 

available technologies and recommended approaches for implementing a testing and monitoring 

plan, including pre-operational geophysical logging and testing of injection wells, MITs, 

injection well testing during operation, groundwater quality monitoring, tracking the CO2 plume 

and pressure front, and soil gas and surface air monitoring, which may be required by the UIC 

12
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: 0143 Comment ID: 23136 Letter Lines: 186 to 193 

Comment Code: 4490 2.4.5 Use of tracers and potential impact on human health or ecosystems 

(seeking comment) 

Comment: techniques would produce reliable data. In addition. there should be no blanket 

requirement for the use of tracers to detect leaks. Such a requirement would 

send an erroneous signal to the public concerning the risks involved in geologic 

sequestration. Geologic sequestration will not develop as a helpful tool in 

reducing greenhouse gas emissions if the wrong signals are sent to the public. 

The utility of tracers for monitoring carbon dioxide leaks is uncertain in any 

event, and the use of tracers may create health or safety issues for workers and 

for the public. 

Individual Response: EPA agrees that the use of tracers should not be required at all GS sites, 

but should be available as an option. For this reason, EPA does not require the use of tracers at 

all GS sites; however, the Director has discretion to require their use if he/she determines that the 

use of tracers could improve monitoring of the site and enhance USDW protection from 

endangerment. The rule will also allow their use if proposed by the owner or operator and 

approved by the Director. 

Comments related to whether the use of tracers will signal to the public that GS is unsafe are 

outside the scope of this rulemaking. However, EPA disagrees that the use of tracers, if needed, 

would signal to the public that GS is unsafe. EPA believes that tracers can be useful tools for 

monitoring, plume tracking, and verification at GS sites and may help improve public confidence 

in certain projects. EPA believes that providing the public with important information about the 

project, including how tracers would be an integral part of the site monitoring plan, will be a key 

part of improving public acceptance of specific projects and GS technology in general. 

Letter ID: 0143 Comment ID: 23137 Letter Lines: 195 to 201 

Comment Code: 4200 2.4.2 Down-hole shut-off valves in GS wells (seeking comment) 

Comment: 4. Down-hole automatic shut-off devices should not be required in all 

cases. TPA disagrees with the proposed requirement of down-hole automatic shutoff devices. This requirement is not imposed upon wells in other classes and 

there is no reason why such a requirement should be placed, on an across-theboard basis, upon Class VI wells. Such a requirement would impose an unnecessary 

expense in many cases. At most, such a requirement should only be imposed on a 

site-specific, case-by-case basis. 

Individual Response: After evaluating the risks and benefits of down-hole shut-off systems and 

13
considering additional research, EPA will not require automatic down-hole shut-off devices for 

onshore Class VI wells since it is not necessary in all cases to ensure protection of USDWs from 

endangerment. Instead, the final rule, at §146.88(e)(2), requires that owners or operators of 

onshore Class VI wells install automatic surface shut-off devices. The rule affords Director's 

discretion to mandate automatic down-hole shut-off devices in onshore situations that may 

warrant their use. However, the Agency believes that offshore Class VI wells present unique 

construction and operational conditions, including isolation from shorelines and the need to 

construct wells through the water column and the subsurface, which may delay response time in 

the event of well difficulties. The rule requires, at §146.88(e)(3), that owners or operators of 

offshore wells within State territorial waters install automatic down-hole shut-off systems. EPA 

believes that these requirements at §146.88(e) ensure that proper precautions are taken to prevent 

subsurface fluid movement and ensure protection of USDWs. 

EPA clarifies that down-hole shut-off devices are currently used in situations where loss of well 

integrity could result in damage to the well or harm to humans (e.g., near high-density population 

areas, or in onshore acid gas injection; IEA, 2003). EPA has identified examples of documented 

logging techniques, including ultrasonic and temperature logs, that can be performed with an 

automatic down-hole device emplaced (Julian et al., 2007; Somaschini et al., 2009). They are 

also used in high pressure, high temperature onshore wells and in permafrost areas. 

Letter ID: 0143 Comment ID: 23138 Letter Lines: 203 to 220 

Comment Code: 1630 1.3.3 RCRA/hazardous waste issues (seeking comment) 

Comment Code: 1640 1.3.4 CERCLA issues (seeking comment) 

Comment: 5. The carbon dioxide stream is a commodity not a waste and should be 

regulated as such. EPA should make clear that carbon dioxide injectate is not 

being categorized or regulated as a waste or a pollutant, but rather as a 

commodity. The sequestered carbon dioxide is expected to generate a credit in a 

future carbon credit scheme. At that point, the act of sequestering the carbon 

dioxide will generate an emission credit that can be sold in the open market. 

Accordingly, TPA urges EPA to remain neutral at this point in time in 

characterizing the carbon dioxide stream as a waste or a pollutant in any of its 

regulatory programs. Those kinds of labels would saddle this program with the 

liability schemes imposed by RCRA or CERCLA and would be severely detrimental to 

the development and use of geologic sequestration technology. It is highly 

unlikely that industry will commit the substantial capital required for geologic 

sequestration projects unless and until the potential for liability is clearly 

defined and understood. Such financial commitment is unlikely to be made if 

participants run the risk of incurring open-ended and ruinous liability under 

RCRA and CERCLA. In this regard, Class VI permits should be written as broadly 

as possible, so as to maximize protections that may be provided by federally 

permitted release exemptions. 

Individual Response: EPA clarifies that the GS rule, being issued only under the SDWA, does 

not affect the status of, or entities’ potential obligations for managing, or liability for 

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management of, CO2 under RCRA or CERCLA. While the Class I requirements formed the 

basis of many of the specific requirements for GS wells, EPA clarifies that the GS rule is tailored 

to the unique nature of GS. EPA based many of the GS requirements on the Class I regulations 

because, like Class VI wells, Class I wells are typically deep and involve waste streams that, if 

not properly managed, can harm the well and lead to contamination. 

In addition, issues related to carbon crediting are outside the scope of the GS rule. Rather, the 

purpose of the GS regulation is to ensure that, where deployed, GS is conducted in a manner that 

protects USDWs from endangerment. 

Letter ID: 0143 Comment ID: 23139 Letter Lines: 222 to 245 

Comment Code: 1614 1.3.1.2 Impurities in captured CO2; purity standards for CO2 

Comment Code: 1630 1.3.3 RCRA/hazardous waste issues (seeking comment) 

Comment: 6. Incidental waste streams in the carbon dioxide stream should not cause 

the stream to be characterized as a hazardous waste or hazardous substance. As 

EPA has pointed out, the carbon dioxide stream may have pollutants in it that 

could cause the waste stream to be classified as a hazardous waste. For example. 

the carbon dioxide stream captured from a power plant may include emissions of 

mercury, a hazardous substance. A carbon dioxide stream captured from a gas 

processing plant may have emissions of nitrous oxides or hydrogen sulfides. The 

incidental presence of these waste streams in a carbon dioxide stream should not 

cause the entire carbon dioxide stream to be classified as a hazardous waste or 

a waste. The proposed regulations do not specify content or constituent 

concentration requirements. They merely state that "[t]his subpart does not 

apply to any carbon dioxide stream that meets the definition of a hazardous 

waste under 40 CFR part 261." Proposed § 146.81(d). TPA urges EPA to establish a 

content percentage or constituent concentration of a pollutant in the carbon 

dioxide stream before the stream is declared a hazardous waste, or some other 

methodology that would promote the goals of this program without compromising 

environmental protection. The cost of removing the offending constituents or 

pollutants could defeat the economic viability of the carbon sequestration 

project, generate additional detrimental air emissions through the removal 

process and in the end be counter-productive as the best longterm disposal 

option for the pollutant may be to sequester it in a deep well. In short, such 

specifications might restrict the amount or kinds of greenhouse gas fluids that 

could be stored through geologic sequestration technology and may defeat the 

program in its entirety. 

Individual Response: EPA recognizes that many CO2 streams may be relatively pure, and 

research indicates that the estimated amounts of impurities in a CO2 stream are likely to be low. 

However, these estimates are based on limited information, and uncertainties remain about the 

expected concentrations of impurities from the various types of CO2 streams. The concentrations 

of minor and trace elements in CO2 streams for GS projects are likely to vary by facility, coal 

composition, plant operating conditions, and pollution removal technologies. 

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The GS rule does not set generic purity standards for CO2 injectate streams (e.g., a percent 

CO2). Instead, the GS rule addresses the quality and quantity of impurities by requiring owners 

or operators to submit information on the source of the CO2 and its physical and chemical 

properties. Specifically, the GS rule requires the owner or operator to submit data about the site, 

including an analysis of the chemical and physical characteristics of the CO2 stream, as required 

at §146.82(a)(7)(iv), and information on the compatibility of the CO2 stream with fluids in the 

injection zone and minerals in both the injection and the confining zones and the materials used 

to construct the well, per §146.82(c)(3). This information can help the Director determine the 

potential for geochemical reactions between the injectate (CO2) and the host geologic 

formations, which could result in the plugging of pore spaces or the dissolution of formation 

minerals. 

EPA received many comments regarding the applicability of the RCRA regulations and statute to 

CO2 streams that are geologically sequestered under the final Class VI UIC well requirements. 

As a result, EPA has decided to initiate a separate proposed rulemaking specifically to examine 

the issue of RCRA applicability to CO2 streams being geologically sequestered, including the 

possible option of a conditional exemption from the RCRA requirements for CO2 GS in Class 

VI wells. EPA will consider these comments as part of its development of that proposal. The 

Agency will consider issues particular to RCRA in the context of that separate rulemaking, and 

recommends that the commenter read that proposed rule when it is published. The Agency notes 

that commenters who wish to submit comments on the RCRA proposal will need to do so during 

the comment period for that rule. Finally, EPA also notes that the final GS rule, which adds new 

regulations for Class VI wells under the Safe Drinking Water Act (SDWA), is not making any 

changes to the RCRA regulations. 

Letter ID: 0143 Comment ID: 23140 Letter Lines: 247 to 262 

Comment Code: 3120 2.1.2 Need to identify additional confining and containment zones 

(seeking comment) 

Comment: 7. Characterization of a secondary containment zone should not be left to 

the discretion of the Director. The proposed regulations provide that at the 

Director's discretion, he or she shall require owners or operators of Class VI 

wells to identify and characterize secondary containment or confinement zones. 

Rather than stating this provision as a requirement to be imposed upon an 

applicant at the discretion of the Director, TPA suggests that EPA establish 

this provision as an additional demonstration to be made by an applicant, in the 

event that a secondary confinement zone is present at the site. The existence of 

a secondary confining zone would make the site more attractive for permitting 

and should be treated as an incentive to make the permitting process progress 

more smoothly and swiftly. A secondary containment zone is certainly not needed 

to ensure safe geologic sequestration. A single containment zone is all that is 

needed. Accordingly, if a secondary containment zone does exist at the site, 

then the applicant should be provided the opportunity to demonstrate that it 

does exist and to receive preferential treatment in the permitting process as a 

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result. 

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

zones, if required by the Director, as proposed (e.g., §146.83(b)). The Agency's decision is 

supported by commenters representing states, water associations, and an electric utility who 

assert that these requirements (at §146.83(b)) promote a flexible, risk-based, site-specific 

approach to characterizing and permitting a site for GS projects. 

EPA disagrees that such sites warrant "preferential treatment." Rather, the Agency expects that 

the extensive site characterization data collected at each site will be evaluated in the context of 

that site (and USDW protection) to support a determination regarding where a permit should be 

issued. The Agency believes 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 (under §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. 

EPA is developing guidance on site characterization for GS projects to assist owners or operators 

and Directors in evaluating permit requirements and applications under §146.82. The guidance 

provides recommendations regarding characterizing the regional geology and hydrogeology of a 

proposed GS site as well as performing the necessary geochemical, geomechanical, and 

geophysical analyses of the injection and confining zone. EPA expects that this guidance will 

assist permit writers in making an objective decision about requiring additional confining layers. 

The guidance can be found on EPA’s website at 

http://water.epa.gov/type/groundwater/uic/wells_sequestration.cfm. 

Letter ID: 0143 Comment ID: 23141 Letter Lines: 264 to 279 

Comment Code: 3862 2.3.3.1 Use of corrosion-resistant construction materials (seeking 

comment) 

Comment Code: 3864 2.3.3.2 Use of corrosion-resistant cements (seeking comment) 

Comment: 8. Imposition of corrosion-resistant materials is too prescriptive. 

Requirements concerning use of particular materials should be imposed on a caseby-case basis. For example, the regulations should not require that all projects 

use corrosion-resistant materials, because isolation and corrosion prevention is 

the result of the proper placement of cement, rather than the type of cement 

used. Any requirement related to the use of corrosion-resistant materials should 

be made on a site-by-site basis. Imposition of inflexible, across-the-board 

materials requirements would unduly hinder development and use of geologic 

sequestration technology, given that the use of conventional materials will 

adequately ensure project integrity in many cases. 

9. Casing material requirements are similarly prescriptive. Requirements 

concerning use of particular casing materials should be based on the planned 

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operating life of the injection program, rather than the life of the storage 

program. Long-term exposure of the casing materials, during storage, can be 

dealt with through plugging if necessary. 

Individual Response: EPA clarifies that corrosion-resistant cement is not specifically required 

in a Class VI injection well. Rather, as stated in §146.86(b)(1), casings and cement used must 

have sufficient strength and be designed for the life of the sequestration project. Further, 

materials must meet standards listed in the rule and be compatible with fluids with which the 

materials may be expected to come into contact. Therefore, some well materials may need to be 

acid-resistant and some may not if they do not come in contact with the CO2 stream or other 

corrosive fluids and if approved by the Director. 

EPA disagrees that the casing, cement or other materials should only be designed for the period 

of the injection process, rather than the life of the sequestration project. GS projects are 

anticipated to have long life spans in comparison to other types of deep injection wells. Not only 

must Class VI wells be able to function safely and properly over the lifespan of the GS project, 

but they must be constructed such that USDWs remain protected after well plugging. The 

requirements at §146.86 will ensure that the well can maintain integrity throughout the proposed 

life span of the project, including after the injection well is plugged and through post-injection 

site care period and beyond. While the risk profile of a GS site will decrease following cessation 

of injection, EPA believes that Class VI wells must be designed to protect USDWs from 

endangerment for the life of the project. Furthermore, rigorous casing and cementing help ensure 

that the Class VI well will not serve as a conduit for movement of fluids associated with future 

injection operations. 

See the 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/wells_sequestration.cfm. 

Letter ID: 0143 Comment ID: 23142 Letter Lines: 281 to 284 

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

USDW 

Comment: 10. Requiring that the injection zone be below the lowermost USDW is onerous 

and unjustified. TPA disagrees with the proposal that geologic sequestration be 

limited in all cases to an injection zone that occurs below the lowermost 

underground source of drinking water ("USDW"). Rather, a performance-based 

Individual Response: EPA acknowledges that there are limited circumstances 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. The 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 between USDWs. 

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EPA believes that these requirements will ensure USDW protection while providing flexibility to 

UIC program Directors and owners or operators who undertake CO2 injection for GS. The 

Agency believes this approach: 1) responds to concerns about local and regional geologic storage 

capacity limitations imposed by the proposed injection depth requirements; 2) allows for a more 

site-specific assessment of injection depth for GS projects; 3) accommodates injection into 

different formation types; 4) allows for injection of CO2 for GS into non-USDWs above and/or 

between USDWs when appropriate and where it can be demonstrated that USDWs will be 

protected; and 5) responds to concerns about the use of aquifer exemptions for GS. Finally, 

EPA’s approach to addressing injection depth variability through a waiver process responds to 

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

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

For additional information on the waiver approach, please see the final rule and preamble, as 

well as EPA's responses to comments on the Notice of Data Availability and Request for 

Comment. 

Letter ID: 0143 Comment ID: 23143 Letter Lines: 284 to 300 

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

USDWs in certain circumstances 

Comment: underground source of drinking water ("USDW"). Rather, a performance-based 

approach should be taken, in which the focus is on the containment qualities of 

the injection interval and on the overall geological environment, not simply on 

whether the reservoir is above or below the lowermost USDWs. TPA would note that 

carbon dioxide has been injected above the lowermost USDWs for decades without 

incident in connection with enhanced oil and gas recovery efforts in Texas. 

Imposition of an inflexible requirement that injection only occur below the 

lowermost USDW would unduly hinder the use of geologic sequestration technology, 

and it would be particularly inappropriate in instances where an injection site 

was situated above a USDW but there was a great distance between the injection 

site and the USDW and the characteristics of the intervening space prevented 

migration between the site and the USDW. EPA's focus should be on the particular 

physical characteristics that are presented, including distance and physical 

characteristics of the intervening space such as discussed above, as well as the 

containment qualities of the injection site being proposed. A site-specific 

approach would increase the use and thus the effectiveness of geologic 

sequestration technology. 

Individual Response: EPA acknowledges that there are limited circumstances 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. The 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 between USDWs. 

The waiver approach requires the submission of extensive, site-specific information (in 

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conjunction with the permit application submission) to demonstrate that injection of CO2 into a 

non-USDW that is above or between USDWs can be done in a manner that is protective of 

USDWs. The requirements are designed to ensure that the owner or operator, the Director, and 

the Regional Administrator consider, on a site specific basis, the implications, benefits, and 

challenges associated with GS and ensuring water availability and USDW protection. 

It establishes: 1) requirements specifying information that owners or operators must submit, and 

Directors must consider, in consultation with PWSS Directors; 2) procedures for public notice of 

a waiver application and for Director-Regional Administrator communication; 3) the waiver 

issuance process; and, 4) additional requirements that apply to owners or operators of Class VI 

wells granted a waiver of the injection depth requirements 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 owners or operators who undertake 

CO2 injection for GS. 

For additional information on the waiver approach, please see the final rule and preamble, as 

well as EPA's responses to comments on the Notice of Data Availability and Request for 

Comment. 

Letter ID: 0143 Comment ID: 23144 Letter Lines: 302 to 312 

Comment Code: 2064 1.5.3.2 Grandfathering construction of Class II wells (seeking comment) 

Comment Code: 2066 1.5.3.3 Grandfathering construction of Class V wells (seeking comment) 

Comment: 11. Grandfathering of well construction standards for Class II and Class V 

wells should be provided without condition. EPA proposes to grandfather the well 

construction standards for a Class II and a Class V well that is converted to a 

Class VI well and requests comments on how this proposal may affect compliance 

with the proposed well construction standards for Class VI wells. TPA believes 

that the construction standards for an existing Class II or V well that is 

converted to a Class VI well should be accepted by EPA as having met the Class 

VI well construction requirements. The meaning of "grandfathering" an 

environmental requirement is just that: the requirements in place at the time 

continue to apply. If this were not the case, a viable sequestration project may 

not occur as development of a new well may be cost prohibitive. 

Individual Response: EPA agrees that many Class II and Class V experimental technology 

wells are designed and constructed to withstand exposure to CO2. The final GS rule provides for 

the construction of these wells to be grandfathered per §146.81(c), provided the owner or 

operator can demonstrate to the Director that the wells were engineered and constructed to meet 

the requirements at §146.86(a) and ensure protection of USDWs, in lieu of requirements at 

§146.86(b) and §146.87(a). 

EPA disagrees that other requirements (e.g., MITs, siting, monitoring, operational, and AoR 

requirements) should also be grandfathered. Following re-permitting of the well as Class VI, 

many of the unique factors of GS sites (e.g., increased reservoir pressures associated with large 

20
volumes of stored CO2 and the corrosivity of CO2 in the presence of water) will result in an 

increased risk profile, warranting the specific requirements in the final GS rule. Therefore, 

following re-permitting as Class VI wells, these projects must be subject to the operational, MIT, 

monitoring, reporting, plugging, and post-injection site care and site closure requirements in the 

final GS rule. See the discussion of EPA's final regulatory approach in the preamble to the GS 

rule for additional detail on these requirements. 

Letter ID: 0143 Comment ID: 23145 Letter Lines: 314 to 320 

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

Comment: 12. The issue of long term liability should be addressed by legislation. TPA 

recognizes that identification of long term liability is beyond this rulemaking. 

However, TPA believes it is important to note that clarification of which 

parties would be responsible for unintended migration or similar problems after 

a well had been closed is vitally important to the long term success of this 

program. Such an issue should be addressed by legislation at either the state or 

federal level. 

Individual Response: EPA clarifies that addressing long term liability by legislation is outside 

the scope of the GS rulemaking. Furthermore, as described above, once an owner or operator has 

met all regulatory requirements under Part 146 for Class VI wells and the Director has approved 

site closure pursuant to requirements at §146.93, the owner or operator will generally no longer 

be subject to enforcement for regulatory noncompliance. 

EPA does not have authority to transfer SDWA or other legal liability for Class VI wells to the 

State or federal government or a third-party fund. See the final rule preamble for further 

discussion of EPA's final approach. 

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