40 CFR Part 192
Standards for Remedial Actions at
Inactive Uranium Processing Sites
                         RESPONSE TO COMMENTS
                               SAR 1166
                          February  28, 1989
                           .Document  #0029g
                     Office of Radiation Programs
                 U.S.  Environmental Protection Agency
                        Washington, D.C. 20460

                            1:   INTRODUCTION

     In this document  EPA  responds  to comments  received  on  the
proposed rulemaking  "Standards  for  Remedial  Actions  at  Inactive
Uranium Processing Sites,"  published  in  the  Federal  Register  on
September 24, 1987 (52  PR  36000-36008).        :'

     Subsequent to the  announcement of the proposed  rule, a public
hearing was held on  October  29,  1987  in  Durango, Colorado.  The  record
was held open until  January  '29,  1988.

     In addition to  requesting  comments  on the  proposed  ground-water
protection standards,  the  Agency  specifically asked  for  comments  on  15
items.  The responses  received  are  summarized in Appendix A.  The
Agency has carefully considered  the views expressed  by  commenters in
formulating this final  rule.  Responses  to selected  comments  on'  these
items are also found in Appendix  A.

     Copies of written  comments  and transcripts of  the  hearing are
available for inspection and copying  at  EPA's Central Docket  Section,
Waterside Mall, 401  M  Street, S.W., Washington, D.C.  20460.   The
docket number is R-87-^01.   (A fee may be charged for  copying.)

     Major concerns  and issues  arising from  written  and  oral  comments
on the proposed rulemaking  are  summarized below.  Each  commenter  is
identified by a letter  and  number after  the  comment.  EPA's response
then follows.  In the  interest  of clarity and economy,  most comments
are paraphrased, and closely related  comments are combined.   A list  of
the commenters with  their  identification numbers is  given in  Appendix
B.  A few comments referred  to  issues that were not  the  subject  of
this rulemaking or concerned wording  of  the  existing  standards that
were repeated in the proposed rule  for clarity.  Such comments are not
included in this document.                        .    •


2.1  General                                       '     .

Comment 2.1.1  The summary  statement  concerning the  proposed
ground-water standards  contains  language that is unnecessarily
absolute,  e.g., the  preamble summary  states  that the  regulations  will
"correct and prevent contamination  of ground water...".   (1-5)

Response  The EPA has  reviewed  the  language  referred  to  and has
concluded that it is not unnecessarily absolute.  When  there  is  a
question as to whether  the  language of the rule itself  or the
characterization in  the preamble  prevails, the  clear  meaning  of  the
rule should govern.

Comment 2.1.2  Language in  the  proposed  standards contains  provisions
that will help to provide  additional  flexibility in  dealing with
ground-water contamination  problems at inactive mill  sites.   We  urge

that any changes to the standards  not make  these  provisions  more
restrictive.   (1-3,G-2)

Response  EPA has not found it  necessary  to  make  these  provisions  more

Comment 2.1.3  Additional flexibility is  needed  in  the  proposed
ground-water standards in order for DOE to  be  able  to demonstrate
compliance within the 1994 timeframe that  the  agency  is seeking  from
Congress.  (G-2,G-8,1-4,1-5 )

Response  Ground-water restoration  is often' a  long-term undertaking.
EPA agrees that DOE is unlikely to  be able  to  completely restore
ground water within the timeframe  that was  allowed  by Congress  for
disposal of the tailings.  Congress has also recognized this  and has
amended UMTRCA to extend the authority of  DOE  with  respect  to
ground-water restoration indefinitely (P.L.  100-616).

Comment 2.1.4 . The differing philosophical  approaches at RCRA and
Title I disposal sites has led  to  conflicting  requirements  in 	
implementing longevity requirements and proposed  ground-water
protection standards.  (G-8)                        -----

Response  The commenter believes that there  are  conflicting
requirements with respect to implementing  longevity requirements under
40 CFR 192 and meeting the proposed ground  water  protection  standards
based on application of current RCRA regulations.   This view
apparently stems from the technical prediction that rock and  gravel
placed on top of an earth-covered  pile to  assure  long-term  stability
will enhance infiltration of water  through  the cover and could  lead  to
ground-water contamination.  We have reviewed  this  matter and have
concluded that covers can be designed to  avoid this problem  by  using
appropriate combinations of drainage and  low permeability layers.

Comment 2.1.5  EPA should reconsider these  standards based  on new  data:

     - The National Research Council's report, Scientific Basis  for
Risk Assessment and Management  of  Uranium  Mill Tailings(1986),
revealed numerous failings in EPA's approach.

     - The. National Research Council's report, Health Risks of Radon
and  Other Internally Deposited.Alpha Emitters  (1988), indicates  that
the  EPA risk- estimate is substantially overstated.

     - DOE has developed extensive  experience  in  the remediation of
Title I sites; EPA's program should reflect  this  practical
experience.  (1-1,1-4)

Response  This comment primarily addresses  the risk due  to  radon from
uranium mill tailings piles and long-term  stability issues for
disposal.  To this extent,  it is only indirectly  relevant to  this
rulemaking.  However,  the Agency considered  the NAS/NRC report

"Scientific Basis for Risk Assessment and Management of Uranium  Mill
Tailings," referenced on page 1-2 of the Background Information
Document  (BID).  Further, the Agency considered DOE experience in
developing the proposed standards, as evidenced by the numerous
references cited in the BID  (see Chapter 3 and 4  in particular).
Finally,  the NAS/NRC BEIR IV report, which was considered  in  various
draft versions during the Agency's development of the proposed
standards, does not indicate that the EPA risk estimate is  overstated;
to the contrary, it is. in substantial agreement.

Comment 2. l.,6  Implementation should be postponed pending  reevaluation
of the regulatory goals and framework applicable  to the uranium
industry.  (1-2)

Response  The regulatory goals and framework applicable to  the
industry  are established by statute, not regulations.  Postponing  the
implementation of these ground water standards for inactive uranium
mill tailings sites will not affect the active uranium industry, which
is already regulated by standards issued in 1983.  Any reconsideration
of those  regulations can be carried out independently of this
rulemaking, which is in response to the remand of specific     _
ground-water provisions, for Title I sites only,,that were  considered
inadequate by the courts.

Comment 2.1.7  These standards should be developed by negotiated
rulemaking between EPA, the affected industry and other interested
parties.  (1-1)

Response  The feasibility of successfully completing .a negotiated
rulemaking, which has been requested by the industry, is being
investigated.  We note that, since the industry is not directly
affected, the present rulemaking can proceed without prejudicing the
regulations for Title II.

Comment 2.1.8  The regulatory analysis does not reflect impacts  of the
regulation on Indian Tribes or related small entities.  (G-6)

Response  EPA considered the general impact of these regulations on
the Indian Tribes and other small entities.  We believe it  will  be .
minor.  In the example provided by the commenter, if there  are farmers
who are now using or planning the use of surface  or ground  waters  that
could potentially be contaminated by mill tailings, then these uses
should be made known to DOE now, so that the cleanup method chosen can
accommodate any future needs in a timely manner.

Comment 2.1.9  EPA should include a concepts section describing  the
major assumptions behind the standards and their  applicability.

Response  The major assumptions underlying the standards  and  their
applicability were described in the preamble  to  the  proposed  standards
and have been repeated in the preamble to the final  rule.

Comment 2.1.10  The interrelationship between Subparts A,  B and  C  is
not clear.TG-2,G-7)

Response  The function of each of the subparts is described by  its
title.  Subpart A applies to the permanent disposal  of tailings  and
the prevention of future contamination from the  disposed  of tailings.
Subpart B applies to the cleanup of contamination from the tailings
piles that has already occurred.  Subpart C contains guidance on
implementation of the standards in Subparts A and. B  and includes
specifications for supplemental standards that can be implemented
under specified circumstances.

Comment 2.1.11  Parts of the proposed standards  and  supplementary
information are vague, confusing, or ambiguous;  both the  BID  and
supplementary information contain errors.  (G-l,G-2,G-6,G-7,G-8,P-2,

Response  EPA has reviewed each specific comment regarding vague,
confusing, or ambiguous information and clarified or corrected  each
point raised where needed.  For example, a comment noted  the  EPA
should define ground-water "use."  EPA does not  categorize water on
the basis of use, therefore, use does not need to be defined  in  these
     Another comment pointed out that organic contaminants have  been
found at the Grand Junction site.  The discussion of organic
contaminants in the BID has been expanded to  reflect the
identification of organic carbon in some ground-water samples at the
inactive sites.
     Other specific comments on particular si.tes we're' reviewed  and
changes made as needed in the BID to clarify and correct  information.
Some items, termed "errors" by commenters, simply reflect  different
sources of data.  For example, a comment notes that  EPA lists a  1.69
mg/1 value for molybdenum in the Environmental Assessment  for
Riverton, whereas the highest value they could find  was 0.9 mg/1.   In
fact, there are 2 molybdenum concentration values greater  than  0.9
mg/1 in this Environmental Assessment (1.1 and 3.7 mg/1).

Comment 2.1.12  The proposed standards may be applicable  or relevant
and appropriate requirements (ARARs) for other DOE programs and,
possibly, non-DOE sites containing large volumes of
naturally-occurring and accelerator-produced  radioactive  wastes.  .The
secondary implementation costs associated with this  standard  due to
such ARARs could be very significant and should  be at least considered
and recognized by the EPA.  While other DOE projects have  begun  to
evaluate the technical and budget implications of the proposed
standard, no budget impact is available at this  time.  However,  it  is
estimated that the costs of implementing these standards  as ARARs
could be in the hundreds of millions of dollars.

     In this regard, DOE manages a number of sites  that contain
low-level radioactive waste as :part of  its Formerly Utilized  Sites
Remedial Action Program (FUSRAP) and Surplus Facilities Management '
Program (SFMP).  Since there may be some broad  interpretations
regarding applicability of the proposed rule for ground-water
standards at UMTRA Project sites, DOE requests  the  inclusion  of  the
ARAR waiver conditions identified in SARA Section 121(d)(4) in the

          The selected remedial action  need not attain the  levels or  ~
     standards of control herein required should one of the following
     three conditions apply:

          o   • The action is only part  of a total remedial,  action that
               will attain such levels  or standards of control when

          o    Compliance with such requirement will result in greater
               risk to human health and the environment than
               alternative options.

          o    The action will attain an equivalent standard  of^
               performance through use  of another method or approach.

Response  EPA considered the above conditions in developing this
proposed rule.  We concluded that only  the second is applicable  to
these sites.  That condition has been incorporated.  However, in  any
case, any DOE sites that are subject to CERCLA/SARA requirements  will
be eligible for all waiver conditions under SARA, unless otherwise
specified in SARA.  Regarding the cost  implications of use  of these
standards as ARARs, it is difficult to  confirm  or refute the  estimate
given.  However, it should be noted that, in general, these standards
simply apply general requirements imposed on contamination  of ground
water from all wastes regulated under RCRA, and that ARARs  for ground
water would, therefore, be essentially  identical independently of
these standards.

Section 2.2  Application of Standards

Comment 2.2.1  Differences between Title I and  Title II ground-water
protection standards should be systematically identified, assessed,
and justified.  (G-2,1-2)

Response  There are several kinds of differences between Title I  and
Title II ground-water protection standards.  In some cases  the
differences are the result of different conditions  present  at the
Title.I sites and are not appropriate to Title  II sites, e.g., the
conditions under which a liner is required.  Other  differences include
specification of additional MCLs and more explicit  guidance on cleanup
of existing contamination.  The reasons for these differences are
discussed in the preamble to the final  standard.. (See also comment

 Comment  2.2.2   It  should  be  clearly  stated  that  Title  II  standards are
 applicable  if  Title  I  and Title  II.tailings are  commingled.   (G-l)

 Response  The  standards  under  Title  I  apply only to those processing
 sites  listed under Title  I or  designated  by DOE  within one year  of the
 promulgation of  UMTRCA as Title  I  sites.   Therefore,  if tailings from
 a  site listed  under  Title I  are  moved  to  and commingled with tailings
 at  a site licensed under  Title. II  or are  reprocessed  through a mill at
 a  Title  II  site, then  the standards  promulgated  under  Title II apply
 to  the commingled  tailings.   EPA is  aware of only one  site (Riverton,
 WY) where this  is  occurring.   However,  cleanup of any  residual
 ground-water contamination at  the  Title I site  from which the tailings
 had been removed will  still  be regulated  under the standards
 promulgated under  Title  I.

 Comment  2.2.3   It  is believed  that the numerical standards for MCLs
 will serve  as  precedents  at  Title  II sites.  (1-2)

 Response  EPA  is considering  the need  to  revise  the numerical
 standards under  Title  II  in  view of  the final standards under Title
 I.  If EPA  should  propose changes  in the  Title.II regulations, they
 would be subject to  normal rulemaking  proceedings.  (But  see also
 comment  2.1.7.)           —*

 Comment  2.2.4  Completed  or  substantially completed sites that perform
 as designed should be  "grandfathered".   (G-2,G-8)

 Response  We have  not  provided any "grandfather" clause for the  six
 disposal actions 'that  are already  complete, or almost  so  (Canonsburg,
 PA; Salt Lake City,  UT; Shiprock,  NM;  Durango, CO; Tuba City, AZ; and
 Lakeview, OR).  Such a clause  would,  in any case, be appropriate only
 for disposal,  not  restoration.   Current indications are that, although
 the covers on  these  piles are  not  quite as  sophisticated  as.later
 designs, performance is exceeding  design  expectations  at  all sites.
 It appears likely that all of  these  covers  will  meet the  standards.
 If not, a variety of remedies  are  available,  including minor
 upgrading,  and ACLs  or supplemental  standards, if appropriate.  In the
 event that  the piles do not perform  as  seems likely, and  none of these
 remedies is appropriate,  modification  of  the standards can be
 considered at a future date.

Comment 2.2.5  Applicability of  the  proposed standards at the more
 than 6000 vicinity properties  should be clarified.  (G-2,G-8)

Response  In the final standards,  we  have clarified that  vicinity
properties are covered by  the  standards.  When,  in the view of the
NRC, a substantial probability exists  that  ground-water contamination
has occurred,  or may occur in  the  future,  the necessary assessments
and corrective measures should be  applied.   It is not  intended,
however,  that the extensive assessment  and  monitoring  provisions
appropriate for large  quantities of  tailings, as at disposal sites,

should be applied when such a substantial  probability  does  not  exist.
EPA expects the implementing agencies, to make  these  judgements.

Sectibn 2.3  Consistency with other Requirements

Comment 2.3.1  Standards for the  reclamation and  closure  of  inactive
uranium mill tailings facilities  must  be consistent -with  those
established for hazardous waste facilities under  the Solid  Waste
Disposal Act (SWDA).  (P-l,G-2,1-5)

Response  We concur, and believe  that  these standards  are consistent
with those established under SWDA, as  is required  by UMTRCA.

Comment 2.3.2  The proposed standard  is inconsistent with SWDA; EPA
has determined that regulation of  mining wastes under  Subtitle  C of
RCRA is not warranted..  (1-4)

Response.  EPA's decision not to regulate mining wastes under
Subtitle C of RCRA does  not apply  .to  uranium mill  tailings.   In making
this decision, EPA specifically noted  that some mine wastes  mig.ht
qualify for Subtitle C treatment.

     This matter was addressed further by  Congress in  the'1980
amendment's to SWDA, which mandated the temporary  suspension  of
regulation under Subtitle C of certain mining  wastes.   The  Conference
Report (No. 96-1444) for the SWDA  amendments of 1980 specifies  that
suspension of regulation of uranium mining wastes  under Subtitle C is
limited to overburden, i.e. regulation of  uranium  mill tailings under
Subtitle C was not suspended.  In  its  decision published  on  July 3,
1986 (51FR24496), EPA reserved the option  of regulating certain
hazardous mine wastes under Subtitle  C.  Since uranium mill  tailings
wastes are about an order-of-magnitude more hazardous  than  other
radium-bearing wastes, e.g., phosphate mining  tailings, EPA decided
that they shall be regulated under Subtitle C.

Comment 2.3.3  Remedial  actions for ground, water  must  be  consistent
with state laws and regulations.   (G-7)

Response  Remedial actions needed  to  implement the proposed  standards
are performed by DOE with the full participation  of any State that
shares the cost (UMTRCA, Sec. 108(a)(D).   This wording indicates an
intent to cooperate with States.   Decisions regarding  consistency with
State laws and regulations with respect to the requirements  of  UMTRCA
are the "responsibility of DOE.

Comment 2.3.4  DOE must  demonstrate compliance with EPA standards at
every inactive site by the end of  the  statutory seven  year  period; if
compliance cannot be demonstrated  NRC  cannot license the  site.

Response  The clean-up of contaminated ground  water  will  take  longer
than the time period Congress originally  specified  for  disposal  of  the
tailings.  In recognition of this fact, Congress  extended  the  time
period for disposal of the tailings  to September  30,  1994  and
eliminated the time limit for the cleanup  of contaminated  ground  water
(P.L. 100-616, November 5, 1988).

Section 2.4  Roles and Responsibilities

Comment 2.4.1  It is unnecessary and  inappropriate  under  UMTRCA,
inconsistent with the Solid Waste Disposal  Act  and  other  legislation,
contradictory of the Tenth Circuit Court  of Appeals  decision  remanding
the Part 192 ground-water regulations, and  inconsistent with  EPA's
UMTRCA Title II standards (which provide  for EPA  concurrence)  for EPA
to let DOE, in consultation with NRC, establish site-specific
alternate concentration limits  (ACLs).  Moreover, in  Title I  unlike
Title II, NRC license jurisdiction is not  implicated  until the
post-remedial period, 42 U.S.C. 7914(f)(2).  This is  a  standard-
setting function that properly  belongs in  some  form  with  EPA  and
should not'be delegated.  (P-3,G-6,G-7)

Response  We considered a number of  approaches  to the question how  to
establish an ACL mechanism.   These included establishing  no ACL-
mechanism, establishing generic criteria  for ACLs, providing  for  some
form of site-specific EPA review or  oversight  of  ACL  implementation,
and (as in the proposed regulation)  providing  for no  EPA  role  in
setting ACLs at individual sites.

     The ACL mechanism in RCRA  was added  after  Congress enacted
UMTRCA, requiring that EPA's general  UMTRCA standards be  consistent,
to the maximum extent practicable, with the requirements  of the  Solid
Waste Disposal Act.  See Section 206(a) (amending the Atomic  Energy
Act by adding Section 275).   It is speculative  for commenters  to  state
what Congress would have intended for EPA's standard-setting  role in a
context it did not foresee.

     Depending on the circumstances  presented,  EPA's  role  has  taken
different forms.   EPA (or RCRA-delegated  States)  administers  the  RCRA
ACL program.   The UMTRCA Title  II regulations  provided  for the ACL
mechanism to be administered by NRC  but reserved  a concurrence
function for EPA.  In the proposed Title  I  regulations, EPA reserved
no concurrence function.

     Without reflecting on. the  merits of  other  approaches,  the
proposed approach was'neither plainly inappropriate  nor unnecessary
under UMTRCA or inconsistent with SWDA.   Nor did  it  represent
disregard of the Tenth Circuit  Court's decision.  As  to the first
point,  this Federally-administered remediation program  at  relatively
few sites is an open process to which a different approach than  that
taken in the Title II regulations could be  appropriate.   Second,  the
UMTRCA mandate to be consistent with  the SWDA where  practicable would
not be violated.   Since NRC is  the concurring  agency, it  is plainly
impracticable and undesirable for EPA to administer  the UMTRCA-ACL
program as if it were the RCRA-ACL program.  Third,  the proposed  ACL

 mechanism  was  consistent  with  the Tenth Circuit Court's mandate:
 these  proposed standards  would establish the numerical standards
 required by  the court,  and  the ACL mechanism mirrored to a substantial
 degree an  existing  Title  II mechanism in order to provide for a
 reasonable degree  of  flexibility.  There was,  finally, no question
 here of  "delegation"  of an  EPA function to another agency but rather a
 question of  how EPA may best carry out its functions. .

     It  is true that  Title  I differs from Title II in.that in Title I
 NRC  licensing  functions are not implicated until the post-remedial
 phase.   (NRC's consultative function under Section 108,  however,
 tracks DOE's remediation.)   But the existence or not of NRC licensing
 jurisdiction does  not answer the question how EPA may best carry out
 its  UMTRCA functions  regarding ACLs or, for that matter, anything else

     EPA has considered that question--how best to carry out its
 function here—in  light of  the comments received urging that, if ACLs
 are  used,  EPA  retain-some form of concurrence role.   It has considered
 this matter  in the  context  of  NRC's present role in  administering,
 with EPA concurrence,  ACLs  at  Title II sites.   We have,  on
 reconsideration, decided  that, in view of the Tenth  Circuit Court's
 remand "...to  treat these toxic chemicals that pose  a ground wa.feer
 risk as  it did in  the active mill site regulations", to adopt the same
 mechanism  for  concurrence on ACLs as was used in Title II.  In
 practice,  EPA  will  use  the  same procedures for its concurrence with
 ACLs as  it does for the Title  II sites.

 Comment  2.4.2   NRC  staff  lacks an adequate reservoir of technical
 expertise  in areas  critical to evaluating proposed ACLs.  (G-6)

 Response   Regulatory  agencies  such as NRC are responsible for
 protecting the public health and environment from a  variety of
 hazards.   NRC  already deals with many aspects of ground-water
 analysis.  However, such  agencies are often faced with technical
 questions  they cannot resolve  without outside assistance and that
 require  them to exercise  one of several options to fulfill their
 responsibilities.   They can hire experts, contract with expert
 consultants, or obtain  the  assistance of other Federal agencies with
 expertise  in the field.  The Agency is confident that NRC has ample
 experience in  such  matters  and will use any and all  of these options
 as needed  to fulfill  their  responsibilities.  In particular, EPA will
 provide  necessary  general guidance on ACL matters to NRC, and will,
 when the ACL involves ground water beyond the site boundary, exercise
'its  concurrence role.

 Comment  2.4.3   It  is  not  clear if an NRC license to  DOE can include
 conditions pertaining to  off-site ground-water contamination.  (G-6)

 Response   Regardless  of the.mechanism NRC choses to  use  to concur with
 DOE1s.actions,  DOE  is required under UMTRCA (Section 101(6)(B)) to
 conduct  remedial actions  at Title I sites including  cleanup of the
 environmental  consequences  of  the tailings that have been dispersed
 prior  to disposal  (Section  108(a)(D).  This includes cleanup of

ground water off site that is contaminated as a consequence  of  the
tailings pile.

Comment 2.4.4  A general license, which we understand NRC  staff  is
considering at this time, is not compatible with  site-specific
analyses in support of ACLs.  (G-6)

Response  NRC is considering issuing a general license for the  24
sites to DOE when the disposal of tailings is complete.  The  general
license will detail the requirements that DOE must apply to  each
site.  If the general license does not accommodate all site-specific
situations, then NRC may have to issue short addenda to the  general
license.  These administrative procedures are the responsibility of
NRC.  In addition,' however, they are responsible  for concurring  in
several site specific determinations as required  in sections  103, 104,
105 and 108 of UMTRCA.  The Agency, believes that  these requirements
and the requirements of the ground-water regulation assures  that each
site will receive individual consideration.

Comment 2.4.5  Does NRC provide an opportunity for public  comme.nt or
input in its concurrence process?  (G-2,G-6)

Response  NRC is planning to hold informational meetings near the
sites before they concur with DOE's surveillance  and maintenance
plans.  These meetings will provide an opportunity for the public, to
express their concerns.  NRC indicates that, even without  these
meetings, if the public has concerns and expresses them to NRC,  NRC
will respond.

Comment 2.4.6  .What are the respective roles and  responsibilities of
NRC and DOE in the licensing process?  (P-3,G-2,G-6)

Response  DOE is responsible for remediating the  mill site,  cleaning
up excess contamination, and submitting plans and reports  to  NRC for
concurrence (sections 102, 108 of UMTRCA).  NRC is responsible  for
assuring that EPA's regulations are satisfied through concurrence with
DOE remediation and issuance of a license for the site when  completed
(sections 104, 105 of UMTRCA).       •                '

Comment 2.4.7  None of the substantive or procedural provisions  of  the
proposed standards acknowledge the state's participation at-crucial
stages in the decision-making process.  (G-7)

Response  The extent of State participation is outlined in UMTRCA,  and
DOE and NRC have included the States in their procedures.  It is,
therefore, unnecessary to restate the extent of State participation in
these regulations establishing standards and criteria.

                                '•  10

Comment 2.4.8  When Indian lands are involved,  there must  be
consultation with the affected Indian Tribes and  the Secretary  of  the
Interior.   (G-6)

Response  The commenter is correct.  UMTRCA requires the DOE  to
consult with affected Indian Tribes and the Secretary of the
Interior.   However, it is not necessary to repeat  these requirements
in these ground-water regulations.

Comment  2.4.9  The clarification of the  respective authorities and
responsibilities under UMTRCA regarding issuance  of ACLs as presented
in these standards is appropriate and consistent  with Congressional
intent..  (1-5)

Response  No response required.

Section 2.5  Institutional Controls

Comment 2.5.1  Few, if any, state or tribal jurisdictions  have  the
authority or the capability to enforce institutional controls over
land use such as EPA suggests.  Also, in  most western states  exTsting
water law does not allow restriction of use based  on water quality.

Response  The Agency recognizes that use  of some  institutional
controls may be difficult, given limited  enforcement capabilities.
Institutional controls other than State and tribal restrictions on use
of ground water are available.  A variety of institutional controls  is
considered in the BID.-, A subjective ranking of these controls  is  made
and discussed.

     The most reliable institutional control is temporary  or  permanent
ownership of land at the tailings disposal sites  by the State or
Federal government.  In most cases, the contaminated ground-water
plumes will be closely adjacent to disposal sites.  States and  tribes
may wish to consider amending their water laws  to  provide  for such
controls,  especially if the costs and benefits  make use of "such
controls a sensible and practical course  of action.

Comment 2.5.2  EPA should not consider use of institutional controls
or land-use restrictions for ground-water protection at inactive
sites; such controls are unreliable and inconsistent with  UMTRCA.

Response  The institutional controls contemplated  would be carried out
under the jurisdiction of DOE and NRC under the legislative mandate of
     UMTRCA requires that the tailings be remediated "...in a safe and
environmentally sound manner and to minimize or eliminate  radiation
health hazards to the public." (UMTRCA, Sec. 2(b)(l)).  We believe
that this requirement can by satisfied under the  provisions of  these
rules.  UMTRCA clearly supports use of institutional control  in a


number of situations:   e.g.,  permanent  retention  of  processing sites
by the United States  government  (Sec.  104(e)(l)(B)  and Sec.  106)  or by
State government  (Sec.  104(b)(D)  and  by  permanent  notice in local
land records  (Sec.  104(d)).

Comment 2.5.3   Institutional  controls  such as  deed  restrictions are
notices, not prohibitions,  unless  there  is a mechanism for
enforcement.  (G-7)

Response  The final rule  states  that  institutional  controls  must  be
effective over  the  entire  time  they  would be in  use  and that deed
requirements would  have  to  be enforced  by permanent  government
entities.  If the institutional  control  cannot  be enforced,  then  that
control could not be  used.

                      Section  3   TECHNICAL ASPECTS

Section 3.1  Ground-water  Standards
                                                               . -*,*._
Comment 3.1.1   The  standards  must  provide for  nondegradation of
beneficial uses to  protect  the  environment as  well  as  public health
arid must regulate nonhazardous  as  well  as hazardous  substances.

Response  We believe  that  these  final  regulations provide for
nondegradation  of beneficial  use,  as well as protective of the
environment and public- health.   The  Act  does not  require standards to
regulate nonhazardous  substances.

Comment 3.1.2   Additional  flexibility  is  needed  in  the classification
of ground waters.   (G-2,G-8,1-4)

Response  It is the policy  of EPA  to maintain  a  single classification
of ground water in  its  regulations to  the maximum extent possible.
Low quality Class II  ground water  may  still be  needed  in the future,
regardless of whether  other'sources  are available or not.   In the
Western States, where  ground  water is  scarce in  many areas,  waters
with total dissolved  solids between  3,000 and  10,000 mg/1 will be
useful as drinking  water or for  other  purposes.   In  any case, we
believe that the supplementary  standards  incorporated  in this rule
provide enough  flexibility  to accommodate any  problem  site that the
DOE remediates.

Comment 3.1.3   The  regulations  should  allow alternate  methods for
estimating background  water quality.   (1-5)

Response  EPA agrees  that water  upgradient of  a  site may not always be
representative  of a site, therefore we have modified the standard to
require a monitoring  program  adequate  to  determine  the background


levels at a disposal site and have  left  it  up  to  DOE  with  NRG
concurrence to determine the details  of  the  monitoring  program.

Comment 3.1.4  The ground-water data  in  the  BID is  based on  site
summaries, not detailed reports, and'contains  unsupported
conclusions.  (G-7)

Response  While it is true that the BID  contains  summaries  of the
detailed reports, the original  reports,  which  included  site
characterization studies, remedial  action plans,  environmental  impact
statements, and environmental assessment reports, were  considered  in
developing the BID.  The purpose of this document is  to provide  a
summary of the information that the Agency  considered in developing
the standards.  The document is not intended, to be  used for  making
decisions .regarding ground-water .protection  at specific sites.

Comment 3.1.5  Pre-existing ground  water at  Tuba  City was  probably
"Class 1".  (G-6)

Response  The statement referred to by this  comment was based O£ the
best information available to EPA at  the time  of  proposal, which'was
that this water was Class II.   The  final evaluation of  ground water at
each of these sites will be made by DOE  and  must  be concurred in  by
the NRC.  In either case, the standards  require restoration  to  satisfy
the provisions of § 192.02(a)(3) .

Comment 3.1.6  At the present -rate  of growth the  Navajo Nation
anticipates a need for  the contaminated  ground waters at the inactive
mill sites within 25 to 50 years.   (P-4,G-4,G-9)

Response  This information should be  communicated to  DOE and,  under
these regulations, will have to be  considered  when  cleanup  of the
ground water at each of the sites on  Navajo  Nation  lands is  carried
Comment 3.1.7  Natural concentrations of nitrates are  elevated  in
parts of. the Western United States;  therefore, it cannot be  assumed
that all elevated nitrate levels  in  the vicinity of  uranium  tailings
sites result from tailings seepage.   (.1-5)

Response  EPA is aware that the levels of many of the  contaminants may
be naturally elevated in the Western  United States.  This  is why the
regulations require a monitoring  program adequate to determine  the
background concentrations of listed,  contaminants.

Comment 3.1.8  It. is difficult to measure gross-alpha  activity  in
water with TDS concentrations over 500 mg/1; most uranium  mill
tailings facilities are located in areas with TDS concentrations over
500 mg/1.   (1-5)   ...


Response  EPA recognizes that  it  is  difficult  to  measure gross-alpha
activity in high TDS waters; however,  it  is  not  technically
impracticable.  Methods do exist  for  the  measurement  of gross-alpha
activity in high TDS waters, the  simplest  of which  is diluting  the
water with distilled water and measuring  an  aliquot of the sample for
the gross-alpha activity.

Comment 3.1.9  Generic criteria and  guidance for  establishing ACLs at
UMTRA project sites should recognize  that  the  remediation at these
sites envisions low maintenance . and. assured  integrity for 1000  years.

Response  The commenter is correct.   The  proposed rules provide that
ACLs may be used instead of MCLs  at  the point  of  compliance where data
provided by DOE support a finding  that  the presence of a constituent
at the proposed ACL would not  pose  a  present or potential hazard  to
human health or the environment.   This  determination  must be made for
the period over which the disposal  is  designed to last, i.e., approval
of ACLs at Title I sites depends  on  reasonable assurance of
conformance (with no planned reliance  on  maintenance)  to the criteria
for ACLs for at least 200 and, to  the  extent practicable, 1000
Comment 3.1.10  The proposed standards are so strict that ACLs will  be
needed for every site, and it may not be  possible  to achieve  consensus
between concerned or affected parties on  ACLs, thus delaying  remedial
actions.  (G-8)

Response , As much as EPA would like  remedial actions to be carried  cut
expeditiously, its main concern is to protect human health and the
environment.  However, the requirements for ACLs in these standards
may be easily satisfied under circumstances where  the opportunity for
hazard to human health or the environment is minor.  (See comment

Comment 3.1.11  Some states with RCRA permitting authority may have  a
nondegradation standard that would preclude use of ACLs.  CG-8)

Response  RCRA permitting authority  does  not apply to these
regulations under UMTRCA.  The decision to conform to such a  State
standard is at-DOE's discretion; DOE may  apply ACLs, if NRC concurs.

Comment 3.1.12  The definition of ground  water should not include the
seepage "bulb" or "mound" beneath the tailings pile.  EPA should adopt
the NRC definition of "aquifer".  (G-2 , 1-4, 1-5)

Response  If the seepage bulb or mound is not hydraulically connected
to an aquifer, then it 'will normally be classified as Class III  (TDS
greater 'than 10,000 mg/1 or insufficient  volume to support a  family)
or an ACL may be applied for at the point of compliance.  If  the
seepage bulb is connected to an aquifer,  then it should normally be
cleaned up.


     Ground water  is defined  in  the  standards,  therefore EPA did not
find it necessary  to define an aquifer.

Section 3.2  Point of Compliance  (POC)

Comment 3.2.1   Clarification  is  needed  concerning  application of the
RCRA regulation  on POCs  to UMTRA  Project  sites  to  reconcile RCRA
intent with UMTRA  Project longevity  objectives.  Location of the.POC
should recognize the specific design differences between RCRA and
UMTRA Project  facilities.  (G-8)

Response  We concur.  These designs,  unlike  those  required for RCRA,
must accommodate the need for radon  control  and  function over
extremely long  periods of time.   Small  amounts  of  seepage that do  not
affect any POE  more than a few hundred  feet  from a pile,  as.long as
this is part of  the property  over  which governmental  control is
exercised in perpetuity, should  provide adequate protection of health
and the environment in all but exceptional  cases.   Application of  an
alternate concentration  level in  such cases  would  be  appropriate.

Comment 3.2.2   The POC provision  in  Part  B  will  require  a complete
description of  the contaminant plumes,  this  will assist  in the cleanup
of chemical pollutants.  (G-3)

Response  No response required.

Comment 3.2.3   It  may be unrealistic to meet ground-water quality
standards at the downgradient uppermost aquifer  beneath  the toe of the
pile.  Some distance from pile edge  is  required  before mixing,
dispersion, and  attenuation reduce concentrations  to  below proposed
limits.   (G-7,G-8,1-4,1-5) .

Response  See  the  response to comment 3.2.1.

Comment 3.2.4   The POC should he  defined  at  some distance downgradient
from the  edge  of the pile and should -include the intervening geology
.as part of the  waste management  area.   A  rational  alternative is to
allow NRC and  DOE  to make the POC  the boundary of  the property that
will be transferred to government  ownership  and  licensed by NRC in
perpetuity.  (G-2,G-7,G-8,1-2,1-4,1-5)

Response  To maintain consistency  with RCRA, these regulations require
that the  POC be  at the edge of the disposed  of tailings.   However,  NRC
may allow DOE  to place additional  wells for  monitoring contamination
of the ground  water from tailings  at any  point as  long as they are
satisfied that  DOE can demonstrate that they are complying with the
standards at the point of compliance.  See  the response  to comment


Comment 3.2.5  The  POC should be concurred  in  by  the  State.   (G-7)

Response  Under UMTRCA,  States do  not  have  a concurrence  role.
However, a State  that pays part of  the  cost of  remediation  may
"participate fully"  in the selection and  performance  of  the remedial
action  (UMTRCA Section 108(a)(l)).  The precise interpretation  of 'this
language is not a subject of this  regulation.
Section 3.3  Remediation Period
Comment 3.3.1  The proposed
restoration is inconsistent
requirements of  SWDA and  is
period of 100 years for natural
with the intent of UMTRCA and the
not supported by analysis.
Response  We believe  an  extended period  for  natural  restoration  of 100
years is consistent with  the  intent  of both  UMTRCA and  SWDA.   UMTRCA1s
intent is that the cleanup  be permanent,  not that  it  necessarily be
concluded as fast as  possible.  The  period selected  is  the  shortest
period that is of significant use  for natural  restoration of  ground
water and the longest period  that  EPA feels  that institutional ^_
provisions should be  relied upon to  protect  human  health  and  the
Comment 3.3.2  Suggestions  that  a  few  years  or  decades  may  be  adequate
to demonstrate natural  restoration  of  water  quality  is  not  supported
by technical analysis.   (G-2,G-6)

Response  A number  of  technical  analyses  have  supported the usefulness
of natural flushing processes.   At  several sites  removal  of
contamination by  natural  flushing, of an aquifer has  been  estimated to
require a number  of decades.  The  DOE  estimates that, at
Colorado, sites,  natural  processes  at  the Old  Rifle  site
contaminant levels  in  the alluvial  aquifer to  background
minimum of two years following disposal of the  tailings.
estimates that natural  flushing  would  restore  the aquifers  at  3  or
additional sites  to compliance with the standards in less than 100
                             the Rifle,
                             could restore
                             levels in a
                              DOE also
Comment 3.3.3  Any extended  remedial  period  and  concurrent
institutional controls should be limited .to  a  20 to  30  year  period
with possible extensions.   (G-7)

Response  Limiting the extended remedial period  to  such short  times
would serve only a limited purpose.   Although  the choice  between  30
and 100 years is ad-mittedly  somewhat  arbitrary,  the  commenter  does not
present a basis for the shorter period.  With  the possibility  of
extensions, the difference becomes  even less and would  be open-ended.
EPA believes that institutional controls cannot  'be  applied  reliably
for indefinite periods.
                                   16 '

Comment 3.3.4  EPA should be ca.utious  in  the  regulatory  use  of  models
and provide procedures and safeguards  to  ensure  proper  use of  modeling
in decision-making.  The development of ground-water  modeling  as  a
predictive tool is still in  its  infancy.  Also, modeling  can  be  abused,
either deliberately or inadvertently.  A  minimum set  of  criteria  that
all models must comply with  should  be  specified.   (G-7)

Response  The comment is well  taken.   However, under  UMTRCA  the
standards that must be met by  DOE are  set by  EPA;  the implementation
and application of those standards,  including the  validity of  any
models proposed for use, must  be concurred  in by NRC.  We do not
believe that it is appropriate to specify criteria  for models  in  the
standards, in part because of  the factors, raised by the  commenter.   In
any case, the regulations require some monitoring  to  verify  the
accuracy of model predictions.

Comment 3.3.5  If modeling is  used,  participating  states and tribes
should be given full access  to the  model  and  its documentation  and
their concurrence should be  required before  recommendations  based on
modeling are implemented at  a  site.  (G-7)

Response  This matter should be  addressed to  the NRC,  since  they  must
concur in the models used by DOE.-     ,

Section 3.4  Monitoring

Comment 3.4.1  Long-term, continual  ground-water monitoring  is  needed
and should be required at all  sites  until it  is  demonstrated that safe
levels of contaminants have  been achieved.   (G-2,G-3,G-7)

Response  Long-term ground-water monitoring  is required  by these
regulations for a period sufficient  to demonstrate  compliance  and the
adequacy of assumptions.  The  actual time will be  decided by DOE  and
NRC after considering site-specific  data.

Comment 3.4.2  The regulations should  specify a  minimum  acceptable
monitoring period as well as parameters for  setting this period.   (G-7)

Response  We disagree.  The  minimum  acceptable monitoring period
should be determined by assessing site-specific  parameters.   This
period will be proposed by DOE and  must be concurred  in  by NRC.   EPA
feels that these government  agencies are  capable of determining the
proper monitoring period (see  previous comment).

Comment 3.4.3  Upgradient monitoring may  not  always be capable  of
providing the desired background water quality information.   (G-2,I-5)

Response  The standards have been modified to simply  require a
monitoring program adequate  to establish  background water quality,
since upgradient monitoring  cannot  always provide  the required
background water quality information.  This will  allow DOE to  use


crossgradient or other monitoring  locations  when  necessary.   (See
comment 3.1.3)

Comment 3.4.4  What provisions are  there  in  the event  that
unanticipated events occur or new  information develops  after  '
licensing?   (G-2)

Response  Should such an event occur  at a remediated site  in  the
future, whatever agency controls the  site would have to  resolve the
problem with the concurrence of the licensing agency,  under provisions
of Section 104(f)(2) of UMTRCA.         '

Comment 3.4.5  Mechanisms for monitoring,  assessment,  and  corrective
action must be a continuing program responsibility  shared  by  DOE and
States.   (G-7)

Response  These regulations require DOE" to establish a  monitoring
program during the disposal period, any extended  remedial  period,  and,
for a specified site-specific period  of time  (comparable in purpose to
the 30-year period required under  Title II)  in the  post-disposaj...
period.   It is therefore conceivable  that some of  these  sites could be
monitored for well over 100 years.  If, during this-'time period,
additional maintenance or remediation  is  required,  it  would be the
responsibility of DOE to see that  such  remediation  or  maintenance  is
performed.  Following the post-disposal period, if  the  State  has opted
to retain ownership of the site, it would be  responsible for  its
continued maintenance.  Should the  site remain under Federal
ownership, the Federal agency involved would  retain responsibility for
its continued maintenance.

Section 3.5  Pile and Liner Design

Comment 3.5.1  The different philosophical approaches  to design and
containment of wastes under RCRA and  UMTRCA  have  led to  conflicting
and mutually inconsistent.requirements  with  respect to  both ensuring
longevity and meeting ground-water protection requirements.   It is-
questionable that the current disposal cell  design, based  on  longevity
and radon reduction requirements,  can  be  engineered to  meet proposed
ground-water protection standards.  (G-8)

Response  The regulations provide  mechanisms, such  as  ACLs and
supplemental standards, to accommodate  those  cases  where design for
radon reduction and design for protection of  ground water  conflict.

Comment 3.5.2  Modification of cover  design  and construction  methods
is necessary; given the present cover  design, it  appears certain that
water will infiltrate and drain from  the  tailings  on a  continual
basis.  (G-6,G-7,G-8)

Response  DOE expects, and preliminary  studies seem1to  confirm, that
the covers are exceeding their design  specifications and will operate


in an unsaturated condition.  In this situation, minor  amounts  of
water will seep through the tailings in  the  1000-year  life  of  the
remediation.   The regulations provide a  mechanism  to allow  for  the
ground water standards to be exceeded to a limited  degree,  when  it  is
not reasonably avoidable, very close to  the  disposal area by allowing
NRC to grant alternate concentration limits  (ACL),  if  it can be  shown
that human health and the environment will remain  adequately
protected.  This process will allow, when necessary, for minor  design
drainage of Jeachate following stabilization of a  pile.

Comment 3.5.3  The final disposal design should possess  the most
impermeable cover reasonably achievable  coupled'with an  engineered
geochemical attenuation system beneath or downgradient  of the
tailings.   (G-6>G-7,G-8)

Response  We anticipate that these standards constituted such  a
requirement,  with respect to cover design.   However, actual disposal
designs are not the direct subject of this rulemaking;  the  condition
of ground water is.  The DOE is responsible  for developing  final
disposal designs that will satisfy the requirements of  the  existing
standards under 40 CFR 192, as well as those promulgated here. ^

Comment 3.5.4  The rock cover on the stabilized tailings will  act as a
one-way valve, allowing infiltration but not evaporation.   Since the
pile covers will be unvegetated there will be  no water  loss through
transpiration.  These factors will lead  to sustained generation  of
leachate from the disposal cells.  (G-6,G-7)

Response  Designs for radon protection and minimizing  leachate
formation are possible.  Because these designs must be  developed on a
site-specific basis, EPA believes that incorporating cover  design
standards into the regulations would only restrict  DOE's flexibility .
and is not in the best interests of the  program.

Comment 3.5.5  Rodents could burrow through  the top liners  at  disposal
sites, bringing some of the radioactive  tailings to the  surface  and
allowing "surface water contamination.  (G-3)

Response  This problem has been studied  in the past (_1,_2) and  has been
found to be avoidable.  Where rodents are a  problem, DOE can take this
into consideration when they design the  cover of the pile.

                      Section 4  RISK ASSESSMENT

Section 4.1 Molybdenum Concentration Limit

Comment 4.1.1  The molybdenum concentration  limit  should be based on
background uses and class of the ground  water, not  on  drinking water
standards.  The proposed standards will  result in  use  of ACLs  at the
majority of the disposal sites; this is  unreasonable.   (G-l)


Response  The standards provide for a supplementary  standard  when  the
ground water is not potable and otherwise  not  of  use.   Any  other water
must be considered as potentially useful as drinking water  and  would
have to meet the drinking water standards.  EPA does not  consider  it
unreasonable to assure, as required by the conditions  for ACLs,  that
public health and the environment will be  protected  wherever  the basic
standards are not met.

Comment 4.1.2  The human toxicology base- was considered  inadequate  by
EPA for setting a general drinking water standard  for  molybdenum.

Response  The human toxicology base is adequate enough,  however, to
establish that .cattle are more sensitive to molybdenum toxicity than
are humans.  The standard was chosen at a  level that will protect
cattle from .developing molybdenosis and will not  prove toxic  to
humans.  Except for a few localized types  of situations  (of which
uranium mill tailings piles is one), molybdenum is not a  problem in
drinking water.  Therefore, EPA is not contemplating establishing  an
MCL for molybdenum under the Safe Drinking Water  Act.

Comment 4.1.3  The proposed standard of 0.1 mg/1  for molybdenum is
unnecessarily conservative; a standard under 0.2  mg/1  is  not
justified.   (G-6,1-2,1-4,1-5)

Response  The above comment is based on data from human  studies.   As
noted above, the EPA standard also the prevents molybdenosis  in cattle

Comment 4.1.4  If standards for molybdenum levels  are  to  be provided,
there should be an analysis made of the forms  of  molybdenum involved
at the sites and the possible effects reductions  in  molybdenum  levels
at the site may have on metabolically related  nutrients.  (P-2)

Response  The information considered by the Agency in  establishing  the
standard for molybdenum took into account  the  forms  of molybdenum  and
its relationship with related nutrients to the extent  such  ,
considerations were pertinent and data were available.

Comment 4.1.5  No risk assessment was made on  the  need for  a
molybdenum standard for the protection of  livestock.   (1-5,P-2)

Response  As indicated in the BID, the molybdenum  standard  is based on
the level in water that will protect cattle and humans from toxic
effects and corresponds to provisional adjusted acceptable  daily
intake (AADI) for drinking water developed by  EPA  under  the Safe
Drinking Water Act (50 FR 46958).  Since the AADI  is set  at a level
that is protective of human health, no further risk  assessment  is


Section 4.2  Uranium Concentration Limits

Comment 4.2.1  The limit for combined  uranium-234  and  uranium-238  is
not scientifically supportable; the uranium  standard is  based  on
faulty weighting factors,  risk estimates,  and  dose  equivalents and  is
extremely conservative.  (G-6,I-5)

Response  The EPA has  revisited the uranium  standard and  has concluded
that it should also consider chemical  toxicity of  uranium  as well  as
the cost implications  of achieving (for  uranium)  the risk  level  of  the
current radium standard.
     EPA is in the process of examining  these  factors, but will  not
reach a decision on the MCL before this  standard  is promulgated.
However, the standard-setting process  has  proceeded far  enough to
assure that the MCL for uranium in drinking  water  will be  close  to  the
limit that was proposed and is promulgated in  this  regulation.   Should
the MCL as finally promulgated be different  from  the limit in  this
regulation, EPA will reconsider the limit  at that  time. .

Comment 4.2.2  A uranium standard on the order of  0.1  mg/1 would be
adequately protective  of public health and the environment.    .^

Response  EPA has revisited the uranium  standard,  and  concluded  that,
based on available information, a standard of  30  pCi/liter is  required
to adequately protect  human health and the environment.   The basis  for
this decision is provided  in the Notice  of Final  Rulemaking.

Comment 4.2.3  Although the general- method used by  EPA in  assessing
the health effects of  uranium is that  of the ICRP,  the assessment
differs from that followed by ICRP in  several  details.   (P-2)

Response  This comment  refers to an advanced notice of proposed
rulemaking on drinking  water standards (51 FR  34836).  It  has  no
direct relevance to the standard being discussed  here.

Comment 4.2.4  EPA uses the ICRP nonstochastic annual  limit on intake
(ALI), not the stochastic  ALI which is more  protective,  yet the  limit
is for a stochastic risk.  (1-5)

Response  EPA used the  ICRP nonstochastic  ALI  in  error;  substitution
of the correct ALI results in a value  of 23  pCi/1.  This  value, •
however, does not include  consideration  of cost.   The  final standard
is within the range being  considered by  EPA  for an  MCL for drinking

Comment 4.2.5  Use of  the  term "urinary  tract"  to  describe what  is
presumably dose only to the kidney is  confusing; if EPA's  weighting
factor includes both kidney and bladder, then  the  risk assessment  may
be too conservative.   (P-2)


Response  This comment must have  been  addressed  to  risk  assessments
performed for another rulemaking  because  we  did  not  use  the  term
"urinary tract" in this  rule.

Comment 4.2.6  The uranium  risk assessment methods  used  were simple
screening methods with high built-in conservatism;  this  is not
appropriate where the • results  can  lead  to high economic  costs
unjustified by the health risks.   More  comprehensive  analyses should
be made using better data to obtain  a  more realistic  picture of  the
risk.   (P-2)

Response  This comment addresses  risks  published  in  a rulemaking  on
drinking water standards and has  no  relationship  or  relevance to  this

Section 4.3  Risk Analysis

Comment 4.3.1  EPA should prepare  a  health and environmental benefits
analysis to support the proposed  standards.   (G-8,I-1)

Response  The legislative charge  under  Title I does  not  envisageT
balancing of costs and benefits.   Rather, EPA is  charged  to  issue
standards that conform,  to  the maximum  extent practicable, to the kind
of protection and clean  up  of  ground water required  under RCRA

Comment 4.3.2  Lack of a satisfactory  risk assessment poses
interpretation problems  in  judging the  reasonableness of  certain
actions.  (G-8)

Response  See the previous  comment.

Comment 4.3.3  Non human health issues  at the Title  I sites,
particularly potential impacts on  agriculture, are  not adequately
addressed.  (G-6)

Response  Cleanup of contaminated  ground  water to these  standards
should protect agricultural uses.  Other  beneficial  uses  of  the  ground
water must be addressed  before ACLs  or  supplemental  standards can be
granted by the NRC.  This should  also  assure adequate protection  of
agricultural uses of ground water.

Comment 4.3.4  Most of the  contaminants found in  uranium  mill tailings
piles occur naturally in undisturbed water and soils  near the tailing
sites and do not include many  of  the organics and contaminants
regulated under RCRA.  (G-6,G-7,1-5)

Response  EPA realizes that many  of  the contaminants  listed  in RCRA
regulations are not found at most  inactive uranium mill  tailings
sites.  However, some of these compounds  have, unexpectedly,  been


found at some sites.  If DOE can
site, then they will not have to
show that they are not
be considered further.'
present at a
Comment 4.3.5  The regulatory assessment  in  support of  the
ground-water standards should include  an  estimate  of  the probability
of exposure and an assessment of the  risk associated  with various
levels of exposure.   (P-2,G-1,1-4,1-5)

Response  The background information  does not contain a probabilistic
assessment of exposure, because to  attempt  to estimate  how many  people
over the indefinite future will use the water from a  contaminated
aquifer is virtually  impossible.   See  also  comment 4.3.6.

Comment 4.3.6  Only 5 of the 12 UMTRA  sites  discussed in the BID have
any current or potential use of the aquifer; the  level  of ground-water
protection should be  based on current  and potential uses of the  local
aquifers.  (P-2)

Response  It is national policy to  protect  ground  water independent  of
current use.
                     Section 5  ECONOMIC ANALYSIS
Section 5.1  Cost Analysis

Comment 5.1.1  The statement that  costs  are  not  to  be  considered  in
the decision to restore contaminated ground  water  (i.e., practical  vs
practicable) appears to be contradicted  where  the  supplemental
standards reference the concept of  technically impracticable.   (G-8)

Response  The distinction between  "practical"  and  "practicable" was
introduced precisely to clarify the meaning  of technically
impracticable.  To repeat:  practical  implies  specifically
costs and benefits, i.e., not spending more  than the  value
benefit obtained.  By contrast, practicable  means  "able  to
practice."  Costs^ if a consideration, would enter only  on
of availability of funds.
                          of the
                          be put into
                          the basis
Comment 5.1.2  Design and construction  cost  impacts  for Subpart  A  have
not been e-stimated as the proposed  standards will  require a unique
technical approach for each disposal  site.   (G-8)

Response  The comment is correct.'

Comment 5.1.3  The proposed standards may  serve  as precedent for other
radioactive waste cleanup projects; this cost  should be considered.

Response  See comment 2.1.12.  EPA  recognizes  that  there  may  be
additional costs if these standards  are  used as  precedent for  other'
radioactive waste cleanup projects.   However,  these  costs can  be
assessed at the time these standards  are  considered  for  use  in other

Section 5.2  Benefit-Cost Analysis

Comment 5.2.1  EPA should assess whether  costs of the proposed
regulations bear a reasonable relationship  to  the benefits as  UMTRCA
requires.  Limited waste cleanup funds should  be expended at  sites
having relatively high impacts on human  health and  the environment.

Response  See the responses  to comments  4.3.1  and 4.3.6.

Comment 5.2.2  There is no experience in  estimating  environmental' harm
that is long-term, manifest, and grossly  disproportionate to
anticipated health benefits.  The record  should  indicate  that
cost/benefit analysis can be used as  a tool to determine  if  the_,
possible environmental harm  is grossly disproportionate  to the health
benefits.  (G-8)

Response  Cost/benefit analysis is a  tool for  balancing  comparable
costs and benefits.  The reference to "grossly disproportionate"  is
intended to preclude such finely drawn balances.

Comment 5.2.3  By the definition of  "technically impracticable from an
engineering perspective," EPA has precluded the  use  of benefit-cost
analyses in assessing potential health effects from  these sites.
However, the discussion on implementation stresses  providing  "the
maximum reasonable protection"; use of the word  "reasonable"  seems  to-
imply some kind of benefit-cost analysis.   (G-8,P-2,I-4)

Response  The definition of  "technically  impracticable from  an
engineering perspective" does preclude the use of cost-benefit
analyses of potential health effects  from contaminated ground  water
for establishing the level of cleanup .at  these sites.
     The concepts of "reasonable" (implying a cost-benefit balancing)
and "technically impracticable from an engineering  perspective" are
incorrectly linked and compared in this comment.  The goal of  the
standards is to provide protection for public  health and  the
environment.   By describing,  this goal as  "maximum reasonable
protection" in the discussion of the proposed  standards,  the Agency
adopted a broad view of "reasonable," not a limited  technical  view of
balancing costs and benefits.

Comment 5.2.4' Cost and benefit considerations should be  included  in
the final standards. • The concept of unreasonably high costs  in
relation to benefits should  be explicitly identified as  relevant  to


the decision that supplemental standards are warranted  because of
technical impracticability.   (G-8,I-4)

Response  There are several reasons for not performing  a cost-benefit
analysis to determine the degree of cleanup appropriate for
contaminated ground water.  First, the benefit  is difficult  to
quantify.  The use of ground  water from any particular  aquifer is
unpredictable, especially over long periods of  time.
     Second, the intent of Congress in providing the similar provision
in CERCLA (§ 121(d)(4)(C)) was not to permit balancing 'of costs and
benefits.  The same section only provides for consideration  of cost
when Superfund would be unreasonably depleted,  resulting in  greater
threat to public health and the environment elsewhere.
     Finally, technical impracticability means  that something is not
capable of being performed, as discussed in supplementary information
to the proposed rule (52  FR 36000).  Thus, cost is not  an explicit
factor in considering impracticability.

Comment 5.2.5  Until both public health benefits and actual  costs of'
remedial actions can be estimated with greater  confidence, cleanup
costs should not be discounted.  (P-2)                         _^

Response  Cleanup costs are discounted to take  into account  the time
value of money, reflecting the likelihood that  today's  dollar is worth
more than a dollar will be worth 10 or 20 years from now.  Public
health benefits are not discounted, because health benefits  do not
behave like monetary costs, as a function of time.


(_!)  Cline, J.F., F.G. Burton, D.A. Cataldo, W.E. Skiens, and K.A.
    . Gano.  Long-term Biobarriers to Plant and  Animal Intrusions of
     Uranium Tailings, PNL-4340.  U.S. Department of Energy, Pacific
     Northwest Laboratory, Richland, Washington 99352 (September 1982)

(2)  Gano, K.A., J.B. States.  Habitat Requirements and Burrowing
     Depths of Rodents in Relation to Shallow Waste Burial Sites,
     PNL-4140.  U.S. Department of Energy, Pacific Northwest
     Laboratory, Richland, Washington 99352 (May 1982).

                    APPENDIX B - LIST OF COMMENTERS
Comment  No.                   Commenter         -          Date  Docketed

                     Organizations and Individuals

P-l                 Environmental  Defense  Fund              01-29-88
P-2                 Dr.  L.  D.  Hamilton; Brookhaven          01-29-88
                       National  Laboratory
P-3                 Southwest  Research and Information      01-29-88
P-4                 Tuba City  Citizens Committee  for        02-11-88
                       Uranium Radiation Control
                          Government Agencies

G-l                 Wyoming  Department  of  Environmental     10-26-87
G-2                 Nuclear  Regulatory  Commission           01-29~88
G-3                 Department  of  the  Interior              12-18-87
"G-4                 DOI  -  Bureau of  Indian Affairs          01-13-88
G-5             v    Texas  Department of Health              01-21-88
G-6                 The  Hopi Tribe                         01-27-88
G-7                 Colorado Department of Health        -   01-29-88
G-8                 Department  of  Energy                   01-29-88
G-9                 Navajo Nation  Department  of  Justice     02-01-88

.1-1                 Foote  Mineral  Company                   10-26-87
1-2            •     Cotter Corporation                      10-26-87
1-3           ,      Pathfinder  Mines  Corporation            11-04-87
1-4                 Kerr-McGee  Chemical Corporation         01-25-88
1-5           .      American  Mining Congress   '             01-29-88

                        APPENDIX A - QUESTIONS

Question 1.  Should a liner requirement always be  imposed on  tailings
piles that are moved to a new location?  Should a  liner be  required
only if the DOE or the NRC conclude that it is needed to satisfy  the
ground-water standards for disposal?

Responses to this ranged from "A liner requirement should be  imposed
on all tailings piles moved to a new location.  This is the least  that
can be done to partially assure that future generations (in the next
1000 years) will not be faced with the same uranium tailings  problems
which we are now attempting to resolve." to "A liner in the ,true  sense
of the word requires leachate collection and treatment... This  is  not
consistent with the specific congressional intent  of a zero to  minimal
maintenance requirement for the inactive uranium sites." (G-4HG-7)

Other views included:

    -A mandatory liner requirement at all new locations, consistent
     with requirements for Title II sites. ^(P-3)

    -The liner requirement should be a rebuttable  presumption;  the
     concern is that DOE or NRC should have an affirmative obligation
     to perform a rigorous geohydrologic analysis  to demonstrate  that
     leachate from the tailings would not have a detrimental  impact on
     potential beneficial uses of a ground water during a period  of
     200 to 1000 years.  A waiver on the liner requirement from EPA
     should be required.  (G-9)

    -Liners should be required at new locations unless DOE could
     present evidence that a liner is not required.  (G-6)

    -EPA has given no rationale for treating DOE less stringently  than
     it treats private_hazardous materials facilities' owners and
     operators or the operators -of active uranium  mill tailings piles
     and, therefore, EPA's standards must impose a liner requirement
     for consistency.  An alternative would be to  waive the liner
     requirement at those sites where the tailings are completely  dry
     and DOE could demonstrate that during both wet cycles and  maximum
     flood events the tailings would remain dry without a liner.   (P-l)

    -The need for a liner should be evaluated on a site-by-site
     basis.  (G-l)(G-2)(G-5)(G-7)(G-8)(I-4)(I-5)

     Liners are relied upon (under S.WDA) to prevent significant
     releases of hazardous constituents only during operations  rather
     than the long-term for which the proposed standards are  intended
     to apply.   DOE and NRC should be allowed to exercise
     site-specific judgement in designing and approving ground-water
     protective measures at disposal sites.  (G-2)(l-5)

     The long-term performance of a disposal cell  will usually  be
     governed entirely by the cap, not the liner.  '(1-4.)

       -  •                         A-l

     If a bottom liner  is  installed  without  an  underdrain .the  disposal
     cell would become  saturated,  leading  to  the  "bathtub"  effect.
     EPA should require  that  the  final  disposal design  possess  the
     most impermeable cover possible (a  maximum of  1  x  10~7  cm/s),
     coupled with a geochemical attenuation  system  beneath  the
     tailings or immediately  downgradient  of  the  disposal cell  as an
     alternative to the  liner  requirement.   (G-7)

     .The low permeability  covers  placed  on UMTRA  Project tailings
     piles inhibit infiltration and  are  the  primary seepage  control
     mechanism.  Where  necessary,  DOE,  with  NRC concurrence, will
     consider the use of a liner  or  a geochemical barrier at the base
     of the pile in addition  to a  low-permeability  cover as  a  possible
     way to satisfy ground-water  standards.   The  need for natural
     liners must be evaluated  on  a site-specific  basis  considering  the
     depth to the water  table, permeability  of  the  foundation
     materials, quality  of the water below the  tailings pile,  and the
     rate and amount of  infiltration through  the  cover  system.  Since
     the UMTRA Project  must design for  1000  years,  and  the  longevity
     of synthetic liners has  not  been sufficiently  demonstrated, liner
     selection is limited  to  natural materials.   The  layered,
     multi-material cover  system  is  designed  for  radon  attenuation  and
     low permeability.

     It was also suggested that if a tailings pile  is to be  relocated,
     the following could also  be  done:  construct  a  low-permeability,
     geochemical layer  at  the  base of the  pile; promote flushing of
     the tailings; or utilize  above-ground disposal.  None of these
     concepts provide an assurance of long-term effectiveness  but
     these, and others  that may be identified,  will continue to be
     evaluated on a case-by-case  basis.   (G-8)


     As noted by some commenters,  the absence or  presence of a  liner
does not by itself assure  the  longevity  of disposal and ground-water
protection.  We believe  that  EPA's proposal,  that a liner not  be
required when water retained  in tailings piles  is not a problem, is
consistent with the Title  II  requirement,  because tailings  at  active
sites may contain large  amounts of water and  therefore  require  a
liner, while tailings at most  inactive  sites  no longer  contain  excess
water.  Requiring a liner  at  all  tailings  pi.les moved to a  new
location is not the best solution.   A liner  that  is less permeable
than the cover may cause water to  pool  in  the tailings, eventually
spilling over the edge  of  the  liner  or  leaking  through  the  liner with
higher levels of contamination (from longer  contact with the tailings)
than if no liner were present.

     The proposed standards require  that DOE, with  NRC  approval,
decide under what conditions a liner may be  necessary.  EPA  agrees
with the majority of commenters that this  should  be a site-specific
determination.  A liner  would  be  required  at  those  sites where  DOE
could demonstrate that  during  wet  cycles and  maximum  flood  events,
ground water would be threatened  in  the  absence of  a  liner.


     It would not be appropriate for  EPA  to  review  liner  decisions  and
cover designs.  Under UMTRCA, the specific analysis  of  the  need  for  a
liner and the design of the cover for  tailings  piles that  do  or  do  not
require a liner is the responsibility  of'DOE, with  NRC  approval.

     EPA has decided to retain its original  position.   That  is,  the
regulations require liners at those tailings piles  which  contain  water
above the level of specific retention.  Tailings  piles  which  are  not
relocated, or are relocated and contain little  or no free  water,  and
are stabilized with an adequate cover  are not likely to require  a
liner to protect ground water.

Question 2.  For designated processing sites from which tailings  have
been removed, is a specific requirement that DOE  clean  up  the ground
water before releasing the land to State  or private  owners  needed to
assure that such cleanup will occur?

Such a requirement is needed.  (P-l)(P-3)(G-3)(G-4)(G-6)(G-7)(G-9)

    -Some sites could revert back to  Department of  Interior  (DOI)
    ' management and any ground-water  contamination  should  be  cl.ft.aned
     up before DOE releases a site back to DOI.   A  related  concern
     expressed is that this rulemaking should require DOE  to  acquire
     full title to any BLM-managed lands  to be  used  as  disposal
     sites.  (G-3)

    -Without such a provision, it is  doubtful that  cleanup  would  ever
     occur by any method other than natural flushing, which the.
     reviewer deems unacceptable.  (G-4)

    —The ground water should be restored  to levels  consistent with
     potential beneficial uses available  prior  to tailings
     emplacement.  Also, to release lands prior to  ground-water
     cleanup is inconsistent with potential  human health  and
     environmental hazards posed by contaminated  ground water.

    -There was implicit recognition that  the standards  would  allow
     flexibility in the amount of cleanup required,  based  on
     site-specific current and projected  use of. the  ground  water.
    -DOE must demonstrate compliance with EPA standards  at  the  time  of
     NRC licensing, which must be within seven years  of  the  standards1'
     promulgation.  There would be no way to enforce  a cleanup  program
     after the remedial action and licensing events have  been
     completed.  Unless EPA's standards  require that  DOE  clean  up  the
     >ground water before releasing land  to other owners,  within  the
     statutory time frame, DOE might either release the  property to
     other owners before cleanup is complete or choose not  to perform
     any clean up and simply retain possession of  the land,
     circumventing the intent of the law and allow creation  of
     environmental sacrifice zones.  (P-l)

    -DOE had  requested provision  in  the  standards for release of land
     prior to ground-water cleanup.   This  request should be rejected
     and release of sites prior to cleanup of  ground water should be
     prohibited.  Such release would  not  be legal since NRG cannot
     license  a  site prior to  cleanup;  such release would not protect
     the public health, safety and the environment as mandated by
     UMTRCA;  and there would  be no guarantee that DOE would complete
     ground-water cleanup.   (P-3)

Such a provision is unnecessary.   (G-l)(G-2)(G-5)(G-8)(1-4)(1-5)

    -DOE is required by Section 108  of UMTRCA  to  comply with standards
     promulgated by EPA.  Also, DOE  has  cooperative agreements with
     affected States/tribes  and the  NRC  requiring their concurrence in
     the remedial action plan.  The  issue  of land acquisition and
     release  is fully addressed in Section 104 of UMTRCA.   In some
     cases, beneficial surface use may be  possible during  aquifer
     restoration and that release for  surface  use, with NRC
     concurrence, should be  permitted  if  the DOE  demonstrates that a
     significant adverse relationship  does not exist between surface
     uses and ground-water restoration.   (G-8)

    -Release  of processing sites  for  surface use, if such  use would
     not adversely impact the ground-water cleanup program, is
     reasonable but may not  be consistent  with the law.  (G-2)

    -Annotation of the deed  would be  sufficient.   (G-l)

    -While it might be appropriate to  release  reclaimed tailings sites
     to a State for limited  purpose  use,  release  to private persons
     should not be permitted.  Need  for  cleanup prior to such release
     would depend on site-specific factors such as contaminant types
     and levels, existing-water quality, potential, uses and
     availability of alternate water  supplies  and surface  uses to
     which the  land may be put.   (1-5)

    -Natural  flushing may often be the most cost-effective means for
     achieving compliance.   This  might require many years  and there is
     no need  to require that  it be accomplished prior to release of
     the land if institutional or other  controls  can assure that
     contaminated ground water is unlikely to  be  put to inappropriate
     use during the remedial period.   (1-4)


     EPA's position remains  the'same  as  originally stated  in the
proposed rules.  Cleanup must .take place in accordance  with a remedial
action plan proposed and carried  out  by  DOE with  NRC's  approval.  The
cleanup must  be carried out  in such a  manner as to be protective of
human health  and the environment.  EPA believes that there are
adequate provisions in UMTRCA and the  regulations to prevent abuse of
contaminated  ground water before  cleanup is complete that  a specific
requirement to assure cleanup is  not  necessary.


     If some sites should be released for restricted  use  before  ground
water contamination is cleaned up, DOE must maintain  control  of  the
cleanup operation.  The DOE does not intend to  return  the  single  site
on DOI land to DOI until it has been completely cleaned up.   Although
DOE must demonstrate compliance with EPA standards before  remediation
is complete, the land may be used before this time for specific
purposes with DOE and NRG approval.  Use of the land  must  be
restricted so that human health and the environment are protected  from
the potential hazards of ground water contamination.   The  land may not
be released for unconditional use until the ground water  is cleaned
up.  Land use restrictions, such as deed annotations,  may  not,
however, be enough unless such restrictions can be legally enforced.

Question 3.  Should institutional controls be relied  upon, for a
limited time, to prevent access of the public to ground water in  order
to permit use of natural flushing of contaminants, as  proposed?   If
so, what types of institutional controls should be allowed?   Should
these be specified in the rule?  Is the proposed time  period

Reliance on institutional controls during ground-water remediation is  .
opposed.  (P-l)(P-3)(G-4)(G-6)(G-7)(G-9)

    -There is no assurance of future enforcement.  (G-4)

    -The proposed period of 100 years is without technical foundation
     and is inconsistent with UMTRCA.  (G-6)

    -Institutional controls during active remediation  are  not objected
     to .but reliance on natural flushing for remediation  is opposed  as
     contrary to the intent of UMTRCA.  If such controls are  used, the
     regulations should require very limited and site-specific
     controls.  Noting that it is inconceivable that Congress would
     have anticipated that the hazards posed by uranium tailings  and
     the accompanying contaminated ground water would  continue
     unabated for 100 years or half the minimum time period for
     effective control, the commenter stated that, if  such controls
     are used, they must provide protection to both human  health  and
     the environment for 1000 years.  (G-9)

    -Reliance on institutional controls provides nothing  in the  nature
     of cleanup; the contaminants will remain dispersed in the ground
     water, possibly diluted by uncontaminated ground  water or
     attached to soil particles, thus permanently contaminating  the
     soils.-  The- only effective institutional control  is believed  to
     be complete fencing, with a security system and government
     ownership of the site.  Such controls are seen as contrary  to
     Section 112(a) of UMTRCA that remedial  action be completed  within
     seven years.  To the extent that EPA can promulgate
     RCRA-consistent controls to accomplish  remedial actions  within
     seven years, those controls should be specified.

     A maximum time of 20 years is suggested for compliance.  EPA
     gives no rationale for choosing 100 years, which  is half the


     lower time limit and appears to bear  no  relation  to  the  seven
     year deadline for completion of remedial action.   (P-l)

    -EPA is urged to  reject any and all  uses  of  institutional
     controls during  the post-closure cleanup period;  these should  be
     used only during tailings stabilization  and  ground-water
     restoration activities at a site.   Institutional  controls  are
     inconsistent with federal law and a federal  appeal court's
     ruling, practically impossible to enforce,  undemocratic  and
     immoral.  The commenter reviews .arguments made  in response to  the
     January 1983 ANPRM and adds that, given  the  court's  order  to
     treat the ground-water standards for  Title  I sites consistently
     with those of the Title II sites, it  is  surprising that  EPA would
     even consider allo.wing use of natural  flushing  as a  substitute
     for active engineered ground-water  restoration  methods.  UMTRCA
     does not give EPA the authority to  require  States, tribes  or
     local 'governments to impose land-use  or  deed restrictions  at
     reclaimed tailings sites.  Since consistency with SWDA is
     required, the existence of an alternate  ground-water  source or
     public water supply should have no  bearing  on  the decision.  The
     suggestion of a  remediation period  of  up to  100 years is opposed,
     citing that it is'the-current generation's  moral  obligation, and
     responsibility to manage and control  the toxic  wastes it creates
     so that those wastes do not harm generations of the  future.   (P-3)

    -If there were a  fully enforceable mechanism  for implementing
     institutional controls, such controls  could  be  considered.
     Unfortunately such controls do not  exist in  Colorado.  Also,
     institutional controls rely on active  intervention whereas
     Congress intended passive control measures.  Purchase of the land,
     in question and  dedication to an appropriate land use is viewed
     as the only implementable institutional  control.   Guidance
     specified in the rules in the area  of  institutional  controls is
     needed.  The proposed time period of  100 years  is too long; it is
     inconsistent with_normal land-use projections.  Instead  use of
     renewable periods of 20 to 30 years is suggested,  with
     participation and concurrence of the  State  and  affected  Indian
     tribes.  (G-7)

Reliance on institutional controls during  ground-water remediation  is
supported.  (G-l)(G-2)(G-3)(G-5)(G-8)(1-4)(1-5)

Acceptable controls should not be specified by EPA,  rather, DOE should
be allowed maximum flexibility to develop  appropriate  controls  on a
site-specific basis,  subject to NRC concurrence.  Suggestions of
possible institutional controls include  legal restrictions enforceable
by government agencies, government ownership  of  the  site,
appropriation of water resources during  period of natural  flushing,
deed restrictions and provision for alternate water  supplies.
(G-2HG-8) (1-4) (1-5)

    -The time period  of 100 years is viewed as reasonable  though in
     some cases this  might not be adequate.   (1-4)(1-5)


    -Consideration of an appropriate  time period  has  been  ongoing
     since 1978 and there seems  to  be  a  consensus  on  the  100  year
     period.  (G-8)

    -The .law requires DOE to maintain  active  site  control  indefinitely
     and to conduct monitoring,  maintenance and emergency  actions  as
     needed.  This long-term care is  under NRC license  and  a  100-year
     period has no meaning fo.r this care.  EPA should  recognize  this
     and take care not to provide a basis for arbitrarily  attenuating
     the DOE obligations.  (G-2)

    -Sites could be monitored by State agencies through federal
     contracts.  (G-5)


     EPA has decided to permit the  use of institutional controls as
proposed.  The regulation requires  that  institutional  controls must
effectively protect human health and  the environment  and  must receive
NRC concurrence.  NRC can require that a Federal  presence  is
maintained during th.e extended remedial  period.   This  assures the
maintenance of institutional controls.                         	 .
     The proposed period of 100  years  for.the natural  flushing of
contaminants is somewhat arbitrary.   Periods  shorter  than  100 years
are considered too short to be useful  for natural  cleanup  for some
sites on technical grounds.  Periods  of  longer than 100 years,
however, are considered too long for  institutional controls to be
reliable.  See section 3.3 of the response to comments.
     UMTRCA provides that cleanup of  ground water  is  the
responsibility of DOE; as long as institutional controls  are  under the
jurisdiction of DOE, they are therefore  consistent with the law  (see
section 2.5 of Response to Comments).
     The UMTRCA requirement that remedial action  be complete  in  seven
years has been modified.  As part of  this modification, the cleanup of
ground water has been exempted from the  remedial  action completion
date.  Therefore, DOE does not have to complete the cleanup of ground
water within a specified period  of  time.
     Authority to require States, tribes, or  local governments to
impose land-use or deed restrictions  is  not required  by these
regulations.  If such restrictions  are available,  then  they may  be
used, where appropriate.

Question 4.  Should the option to make use of natural  flushing for
cleansing of contaminants be limited  to  cases where some  restoration
of the ground water has already  been  carried  out?  Should  the use  of
an alternate concentration limit (ACL) be permitted,  as proposed,  in
the case of cleanup to be achieved  (in whole  or part)  by  natural

The use of natural flushing and  ACLs  in  ground-water  restoration is
opposed.  (P-l) (P-3) (G-6.)

    -Natural flushing is based on theoretical projections,  with
     possible delays in recognizing any  inadequacy and  no  regulatory
     or legal basis for corrective  action.  (G-6)


     -These  options would  result  in cleanup at certain sites being
      waived entirely  through  a combination of waiving regulatory safe
      levels of  contaminants  by a grant of ACL and then waiving active
      cleanup  in  favor  of  a passive program which entails the masking
      (through absorption, dilution or decreases in ground-water
      quantity)  rather  than the actual removal of human-introduced
      contaminants.   (P-l)

•Consideration of  natural  flushing or use of ACLs only after all other
active  aquifer  restoration methods have been employed is favored.

     -If  natural- flushing  is  allowed, the flushing period should be
      reduced  from 100  years  to a shorter period to allow use of other
      remediation  measures if  the flushing is not successful.  ACLs
      should be  used  only  where active restoration efforts demonstrate
      that complete cleanup is not achievable with available
      technology;  in  no  event  should ACLs be considered as the initial
      goal for aquifer  cleanup.   (G-9)

     -While  there  may  appear  to be some merit in requiring an initial
      active cleanup  phase followed by passive measures,  very li.t,tle
      cleanup  is  achieved  if  active measures are implemented for only a
      year or  two. - This requires large amounts of funds  with little
      accomplishment.   A suggestion instead of an engineered, enhanced
      natural  flush (EENF) system representing innovative
      implementation  of  fundamental concepts such as high permeability
      trenches,  nonconsumptive irrigation ditches for altering the
      hydraulic  gradient on a  local scale, and perhaps some chemical
      agents to  enhance contaminant flushing from soils is made.  In
      perhaps  two  or  three decades cleanup by this approach would
      easily exceed any  short  term improvements obtained  by a temporary
      pump-and-treat  program.   Such a system would be less expensive
      than pump-and-treat, permanent, and require minimal or 'no
      maintenance.  The  commenter feels that ACLs could be used as part
      of  larger  cleanup  strategy  such as the EENF concept but does not
      believe  that they  should be applied at any site relying solely on
      natural  flushing  with no attempt or plan to clean up the existing
      contamination.   (G-7)

This  option should.not  be limited and use of ACLs should be
permitted.  (G-l)(G-2)(G-5)(G-8)(1-2)(1-4)(1-5)

     -Natural.flushing  should  be  allowed in conjunction with active
      restoration  or  as a  sole mechanism for cleanup if the
      concentrations  of  contaminants will decline to appropriate levels
      within the period of institutional controls.   If some active
      restoration  is  required  prior to natural flushing and.
      institutional controls,  the extent and objectives of partial
      restoration  will  be  extremely difficult to establish.  Specific
      guidance regarding the  objectives of such limited restoration
      should be  developed  and  provided to DOE for review  prior to
      promulgation.   ACLs  should  be permitted where ground-water
      restoration  would  involve natural flushing.  The guidance for
      issuance of  ACLs  requires demonstration that the hazardous


     constituents detected in the ground  water  will  not  pose  a
     substantial present or potential  hazard  to human  health  or  the
     environment at ACL levels.  Given  that ACLs will  protect human
     health and the environment  in  the  specific hydrogeologic
     circumstances, it is reasonable that ACLs  should  be  permitted for
     all cases of cleanup.  (G-8)

    -Decisions on active and natural restoration will  likely  be
     site-specific and the flexibility  to use  natural  restoration
     alone should be retained.   Approval  of the ACL  means that  the
     contaminant concentrations  do  not  pose significant  present  or
     potential hazards to humans or  the environment.   Natural flushing
     to reach backgrou-nd or drinking water levels would  provide  an
     additional margin of safety.   (G-2)

    -To limit the use of natural flushing to  those cases  where  some
     restoration has been performed  would place unnecessary
     res'trictions on the ability of  DOE to achieve cost-effective
     protection of public health.   For  the same reasons  ACLs  should  be
     permissible in cases where  natural flushing is  permitted in whole
     or part.  The establishment of  ACLs  is predicated on a finding
     that public health and the  environment will be  protected. _.(I-5)  .

    -The natural flushing option should be allowed in  all cases  where
     the physical characteristics .of the  ground-water  system  are
     favorable.  If ACLs cannot  be  established  for sites  using  natural
     flushing, accelerated flushing  will  be required.  The end
     results, effectiveness of the  remedial action,  will  be identical,
     but the costs will be much  higher.   (1-2)


     In this question, natural flushing was assumed  to be a viable
alternative.  In order to use this  option, the  regulations require DOE
to establish a program to monitor the progress  of natural flushing.
At any time they determined that the flushing  was not  proceeding as
projected, they could modify the remediation.   Periods shorter  than
100 years are considered too short  for  natural  cleanup of some  sites
on technical grounds.
     Alternate concentration levels  (ACLs) may  be applied to  a  site
only if'DOE can show that human  health  and the  environment are
protected.  In order to apply an ACL during natural  flushing,  DOE
would have to show that the requirements  for an ACL  will  apply
throughout the area affected, by  the  ground water.
     Therefore, EPA's position remains  as in the proposed regulation.
If passive restoration is projected  to  occur naturally in 100 year's  or
less, the ground water will not  be -used as a public  drinking  water
supply, and institutional controls  and  a  monitoring  program are
implemented, the remedial.plan may  rely in part or full  on natural
flushing.  ACLs may be used where justified.

Question 5.  Are the proposed bases  for supplemental standards  for
cleanup reasonable and adequate  for  the protection of  public  health?
Should other bases be provided and,  if  so, what are  they? Should the


 provisions  for  natural  flushing  and supplemental standards for
 cleanup -apply only to existing contamination or should they also
 apply/  as  is  proposed,  to "new"  contamination due to failure of the
 disposal design to perform as intended?

 Reliance on the draft Class III  ground-water classification criteria
 at  the  UMTRA  Projects is  opposed.   The second criteria, restoration
 causing more  environmental harm  than' it would prevent is acceptable if
 it  is  made  clear in the final rule that Congress and EPA's
 determination that there  are  real  public health and safety and       »
 environmental hazards associated with nonradiologic contaminants from
 UMTRAP  sites  requires that DOE and NRC admit to the environmental
 benefit of  clean up.  The third  criteria,  technical impracticability,
 is  acceptable only if EPA dan fashion a sufficiently specific
 definition  of the term  "technically practical" to make implementation
.possible.   (P-l)(P-3)

     -There  appears to be  a fourth  criterion, where passive restoration
     of an  aquifer can  be projected to occur naturally within a period
     of less  than 100 years and  the ground water is not now used or
     projected  to be  used for a  community  water supply.  Because of
     the inability to accurately predict the potential for future use
     of an  aquifer as a community  water supply, this circumstance
     should not allow a facility to meet higher contaminant levels
     than  those set by  the regulations.  The commenter would not
     support  any further  bases.   The provisions for natural flushing
     should apply, if at  all, only to existing contamination.  (P-l)

     -Only  listed contaminants are  addressed; this may not be
     reasonable for protection of  public health.  (G-9)    ,

     -The proposed bases are sufficiently broad to be easily
     implemented or nearly impossible to implement, depending on
     approaches taken by  DOE  and NRC.  In  any case, the requirements
     are not  met for  the  Tuba City site.  (G-6)

 Any  standards set for clean up of  ground water must apply to new
 contamination resulting from  failure of the disposal design to perform
 as  intended.   (G-4HG-7)

     -Additional modifications to the current disposal design will
     improve  its hydrological and  contaminant release performance and
     supplemental standards should not be  allowed at new disposal
     sites  until Colorado and independent  experts agree that the best
     available  technology has been applied to the impoundment design.

     The proposed bases for application of supplemental standards were
     not entirely adequate,  and  EPA and the implementing agencies
     should develop specific  guidance in such areas as determination
     of the potential for future changes in land use at processing
     sites  and  cost/benefit analysis.  (G-7)

     -EPA should consider  adding  consideration of costs when such costs
     would  be unreasonably excessive in relation to the benefits .to be
     gained from reduction of risks.  Maximum flexibility should be


      retained,  including  the  flexibility  to  consider  natural  flushing
      and  supplemental  standards.   (G-2)

     -Explicit  consideration of  costs  should  be  included  in  the
      regulations, and  a more  expansive  interpretation of Class  III
      ground  water should  be allowed.   The provisions  authorizing
      natural flushing  and  supplemental  standards  should  always  apply.

The  proposed bases  for supplemental standards  are reasonable  for  the
protection of  human  health and  the environment  but  the bases  should be
extended  by  specifically  including consideration  of costs and benefits
and  clarifying  that  ground-water  restoration is not necessarily
required  when  supplemental standards  are  invoked.   Supplemental
standards and  natural  flushing  should  also apply  to new  contamination
due  to failure  of the  disposal  design  to  perform  as intended; the
commenter notes  that supplemental  standards  can be  applied  only when
.the  ground water has an extremely  low  potential for extraction  and  use
and  when  sufficient  remedial  action is  undertaken to  protect  human
health and the  environment.   (G-8)

      The  restrictive definitions  of the first  and last criteria are of
particular concern.  A suggestion  was  made that the basis for
determining  applicability  of  supplemental standards should  be based on
a site-specific  analysis  of the  risks  presented to  public health  and
the  environment  and  a  similar analysis  of the  full  range of
alternatives for achieving public  health  protection including the
environmental  and economic costs  of each.   This decision should be
made  based on  expert judgment along the same 'lines  and with same
considerations  as for  establishing ACLs.  .The  provisions for  natural
flushing  and supplemental  standards should apply  to new  contamination
as proposed; the controlling  consideration should be  protection of
public health.   (1-5)


      The  commenters  felt,  for the  most  part, that the proposed  bases
for  natural  flushing and  the  supplemental  standards were adequate for
the  protection  of human health  and the  environment.  The suggestions
that  cost be considered as a  basis for  natural  flushing  or  a
supplemental standard  were not  incorporated.
      The commenters  did not provide any substantial reasons for not
applying  natural flushing  or  the  supplemental  standards  to  new
contamination  from tailings piles  due .to  failure  of the  disposal
design to perform as intended.  Therefore,  EPA  will continue  to allow
application of  natural flushing or supplemental standards to  new

Question  6.  Under these proposed  standards, alternate concentration
limits would be concurred  in by the NRC.   Should  EPA  establish  generic
criteria and/or guidance governing the application  of the provisions
of 264.94(b) of this Part  to these judgments for  these standards?


Generic criteria and/or guidance  is  not  needed;  Section  264.94(b)
provides a clear health, safety and  environmental  finding  and  a  list
of factors to be considered in establishing  ACLs.   (G-2)(1-4)(1-5)

    -A methodology-for establishing  ACLs  at  Title  II  sites  is
     currently being developed.   (G-2)

    -NRG, like EPA, is constrained by UMTRCA to  assure that  actions
     taken by it under that Act adhere to  the paramount  purpose  of
     protecting public health and the environment  from unreasonable
     risks.  Also, as a practical matter,  EPA will  have  an  opportunity
     to provide input to setting  the ACLs  through  comments  on  site
     EISs and consultations between  agencies.   (1-5)

    -NRC and DOE should be allowed to exercise  their  judgment  without
     additional guidance from EPA.   (1-4)

Generic criteria and guidance are supported  for  differing  reasons.
(P-l)("G-6)(G-7) (G-8)

    -EPA should provide additional flexibility  to  the RCRA  ACL
     guidance, specifically regarding the  point  of  exposure,  th.e_, .
     period of applicability of ACLs, release of contaminants  to
     surface waters, and other provisions.   (G-8)

    -Given ACL delegation to NRC, EPA guidance  and  concurrence  in NRC
     procedures is absolutely critical.   (G-6)

    -Guidance is necessary to ensure consistent  interpretation.   (G-7)

    -Guidance might be an acceptable way  to  ensure  that  NRC does not
     accept ACLs which are inconsistent  with EPA's  standards.   (P-l)

The delegation of ACL concurrence to NRC  is  specifically objected to.

    -NRC has regulatory' authority over the  radioactive contaminants
     only and nonradioactive contaminants  are regulated  under  this
     rule and subject to- ACLs.. (G-9)

    -DOE's consideration of ACLs  might be  facilitated if generic
     criteria are provided.  (P-3)

State and tribal concurrence should  also  be  required, • since  these
entities are directly affected and are in  a  better  position  than NRC
to evaluate ACLs.  (G-4HG-9)


     Establishment of regulations for generic criteria for  granting
ACLs would present extreme difficulties  for  rulemaking,  since  it often
involves complex judgments that are  not  amenable to being  reduced to
regulatory requirements.  In this regard we  note that such  regulations
do not exist for sites directly regulated  under  RCRA, for  similar
reasons.  We have reconsidered the issue  of  EPA  approval of  ACLs and


decided to retain the approach  implemented  in  the  Title  II
regulations.  That  is, EPA has  reserved  a concurrence  role  for  any  ACL
that would result in the otherwise  applicable  ground-water  standard
not being met at.the site boundary  or  500 meters  from  the disposal
area, whichever is  closer to  the  point of compliance.  This  approach,
in addition to  responding to  the  concerns voiced  by  commenters,  also
adheres more closely to the Court's admonition to  treat  these
pollutants "...as it did in the active mill  site  regulations."   It  is
EPA's intent, in carrying out this  concurrence role, to  adhere  to the
same generic procedures for ACLs  that  it applies  to  the  Title II sites,
     EPA is required by UMTRCA  (Section  206) to be consistent,  to the
maximum extent  practicable, with  RCRA.   For  this  reason, we  have
incorporated relevant portions  of the RCRA  regulations.'  These
regulations provide for use of  ACLs when 'it  can be shown, that the
criteria specified  in § 192.02(a)(3) (iii)(B) are  satisfied.  It
remains the view of the Agency  that, as  at  the Title II  sites,-  it is
not necessary for EPA to retain a concurrence  role if  the NRC has
determined that these criteria  are  satisfied when  the  otherwise
applicable standard will be met within the  site boundary (or at  a
distance of 500 meters, if this is  closer to the  point of
compliance).  It is clear for controlled minor seepage within site
boundaries and  when public use  is not possible, that ACLs will ..usually.
be appropriate  in such situations.
     The participation of States  in the  application  of these standards
has been discussed  previously (see  comments  2.3.4, 3.1.11,  3.2.5).

Question 7.  Should EPA publish,  as part of  this  standard,  a
restricted list of,  just those radioactive and  toxic  constituents that
are present at1these sites, or  continue  to  rely on the entire list
(supplemented as proposed) of constituents  encompassed by RCRA
regulations?  Should the proposed list of additional listed
constituents be changed?

A restricted list is either inappropriate or not  needed  for  this
standard.  (P-l)(P-3)(G-2)(G-4)(G-7)(G-8)(G-9)(1-5)

    -DOE's general  approach to  characterizing  ground-water
     contamination  is to apply  a  screening  level,  multiphased program
     for all suspected contaminants.  This  is  followed by detailed
     determination  of those contaminants detected  by the screening
     program.   The  proposed list  of additional listed  constituents
     should not be  changed.   (G-8)

    -While a limited constituent  list might  be a  good  idea,  the  sites
     have not been  fully characterized and  new constituents could be
     identified.  The existing  provisions for  DOE  identification and
     NRC concurrence provides sufficient flexibility to  accommodate.
     any new constituents found at  the sites.   The site  specific
     nature of  the  issue almost precludes defensible standards  until
     all sites  are  evaluated  and  the need no longer  exists.  (G-2)

    -Ground water needs to meet requirements for  irrigation and
     livestock  watering in addition to human health  concerns, thus  any
     listing should be broad  enough to allow for  cleanup based  on


     agricultural requirements and should mandate cleanup  for any
     reasonable purpose for which the water might be  used  for 1000
     years.  Unanticipated levels of arsenic were discovered during
     remediation at the Lakeview site and, under the  proposed rule,
     the unanticipated contamination would not have been remediated.

    -Experience with some of the actual mill sites has  shown a  variety
     of unexpected chemicals can be encountered in drums and as
     residual contamination from operation of the mill.  (G-7)

    -EPA should not publish a restricted list but should leave  it to
     DOE and NRC to develop such a list based on what they  find  at  the
     various Title I and Title II sites.  NRC',s Uranium Recovery Field
     Office has provided data from 17 sets of samples at nine tailings
     ponds; each sample was tested for 150 potential  ground-water
     contaminants and none of the samples indicated the presence of
     any of the 12 volatile or the 81 semi-volatile organic compounds
     tested for.  The limits set for the additional listed
     constituents should be changed.  (1-5)

    -EPA recognized in the proposed rule that some organics were., used
     at the UMTRAP sites, even though present monitoring has yet to
     show presence of any organics.  It may, however, be appropriate
     to allow use of a restricted list after initial  ground-water
     screening at a site established that no organics were present.
     (P-l)                                               .

    -Analysis of one set of ground-water samples for  all Appendix VIII
     constituents and for any other pollutant or contaminant present
     at each site either in the tailings themselves or  in  the ground
     water is recommended.  DOE could eliminate constituents not
     detected; such a list would be site-specific'.-  Water  samples
     should be analyzed for certain indicator contaminants such  as
     sulfates, chlorides, total dissolved solids, and major cations
     and anions at each site.  Nontoxic contaminants  must  be addressed
     to protect agricultural uses of ground water.  Monitoring  for
     these indicator contaminants is necessary to guide decisions on
     ground-water remediation techniques - a variety  of aquifer
     restoration methods are now available but no one method
     adequately addresses all pollutants.  Finally, the commenter.
     disagrees with EPA's assumption that any minor contaminants would
     be taken care of in cleanup of the principal contaminants.  (P-3)

Publication of a restricted list is supported.  (G-5)(1-2)(1-4)

    -Supported only if it would not delay the rule.   (G-5)

    -The list should include only those radioactive and toxic
     constituents that are present at the inactive sites.  Most  of  the
     synthetic chemicals that EPA has identified as being of
     particular concern under RCRA simply are not found at tailings
     sites.  EPA should change the proposed list of additional
     constituents because the limits are not scientifically
     justified.  (1-4)


    -The regulatory approach should be changed to include
     contamination of ground water with nonhazardous  constituents  that
     compromise beneficial uses of the water.  (G-6)


     EPA agrees with the majority of commenters  that  the entire  list
of hazardous constituents should continue to be  relied on  for  these
regulations.  The finding of organic compounds at some of  the  sites
and the unexpected levels of arsenic at the Lakeview  site  reinforce
the need for the complete list.  Where relevant  new MCLs have  been
approved, they have been added to table 1.  Adding nonhazardous
constituents to the list because they- inhibit beneficial uses  of .the
water is not viable.  The purpose of these regulations is  to protect
human health and the environment from the radiation health  hazards of
the mill tailings and to minimize other environmental hazards  from
such tailings.  Nowhere are nonhazardous constituents mentioned;
therefore,  these constituents are not addressed  by these regulations.

Question 8.  EPA could consider publishing a restricted list of  just
those radioactive and toxic constituents that are principal    _ .
contaminants at these sites and specifying a limit for each of these,
under the assumption that any minor contaminants would be  taken  care
of in the cleanup of these principal contaminants.  With such  a
restricted set of constituents and corresponding complete  set  of
limits, EPA could then consider dropping the provisions for ACLs and
rely solely on the remaining provisions for exceptional cases.   Should
EPA adopt this approach?

The restricted list is opposed or is not warranted, and .the ACL
provisions should be retained.  (G-2)(G-4)(G-7)(G-8)(G-9)

A restricted list is supported or accepted but the ACL provisions
should be retained.  (P-l)(1-2)(1-4)

    -The ACLs provided needed flexibility.  (G-2)(G-8)

    -Developing ACLs with concurrence of the affected States and
     tribes is favored for exceptional cases.  (G-4)

    -The commenter disagrees with the assumption that minor
     contaminants would be taken care of in the  cleanup of  the
     principal contaminants and, also noted that it would  seem more
     appropriate for the standards to reflect the philosophy,  if not
     the specific wording, of the CERCLA aquifer restoration
     requirements.  (G-9)

    -The loss of flexibility would impede selection of cost-effective
     remedial actions.  (1-2)

    -This approach is feasible only if EPA's assumption regarding
     removal of minor contaminants is true; EPA  must  be able to


     demonstrate that the cleanup methods chosen for  the principal
     contaminants will also remove any organics that  may be  present.

    -It is appropriate to focus the regulations on  the principal
     contaminants but the ACLs are necessary to enable DOE to  consider
     site-specific conditions and select appropriate  remedial
     actions.  (1-4)

    -The concept of a restricted list and the assumption that  cleanup
     of the principal contaminants would also clean up minor
     contaminants is supported.  It is felt that ACLs will still  be
     necessary for flexibility in addressing site-specific conditions
     on a cost-effective basis.  (1-5)

    -EPA needs to provide generally applicable standards sufficiently
     well guided technically to ensure that potential beneficial  uses
     of ground water will be protected following remedial action.   It
   '  is unclear even conceptually how this could be done by  narrowing
     matters of regulation and hoping that everything else will take
     care of itself.  (G-6)


     As in the previous question, EPA has determined  that the  entire
list of hazardous constituents should be retained.  The unexpected
discovery of some organic compounds at some sites underscores  the need
for the complete list.  In addition, since those compounds that do  not
have an MCL listed would have to be cleaned up to background  (which  in
the case of organics would be zero) or be granted an  ACL, EPA  has
added MCLs to Table 1 of the standard for those relevant compounds  for
which MCLs have been established.  EPA believes that  ACLs provide
needed flexibility and have decided to retain them  in the regulation.

Question 9.  Should EPA specify a minimum or the entire period for
post-disposal ground-water monitoring in Subpart A, or leave  it to  the
DOE and NRC to determine this on a site-specific basis, as proposed?
If EPA should specify a period, what- length would be  appropriate  to
demonstrate conformance to the disposal design standard, and on what
basis should this value be chosen?

Selection of the monitoring period should be left to  DOE and NRC  to
determine on a site-specific basis.  (G-l)(G-2)(G-8)(1-4)(1-5)

    -DOE would use factors in 40 CF'R Part 264.117 in  establishing
     the site-specific monitoring period, subject to  NRC review and
     concurrence.  A memorandum of understanding addresses the basic
     requirements applicable to Title I sites and the site
     surveillance and maintenance plans address specific site
     requirements.  (G-8)

     Monitoring may not be required at certain disposal' sites; e.g.
   •  sites where the uppermost aquifer is insulated by thick sequences
     of low permeability and/or highly attenuating materials,  sites


     above Class III waters, or sites  where  the water  table  is  deep.
     Because of this, monitoring should not  be mandatory.  Should  the
     proposed standards be ARARs at  other DOE sites  (e.g.
     FUSRAP/SFMP), the definitions of  "remedial period"  and
     "post-disposal period" would need to be revised to  reflect  the
     unique concerns of those sites; EPA should clarify  that  these
     definitions apply only to the UMTRA Project.   (G-8)

    -Performance objectives should be  provided for  site-specific
     flexibility instead of specifying a post-disposal monitoring
     period.  (G-2)

    -The monitoring period will depend on the nature and  severity  of
     the hazard posed by any contamination,  stability  of  the  site, and
     rate of movement of such contamination; at some sites three years
     may be sufficient, at others five years or more may  be  necessary
     to demonstrate conformance with disposal design standards.   (1-5)

Specification of a minimum monitoring  period, usually  in  the  range
from 30 to 100 years, is supported to  assure that the  design  criteria
perform as anticipated.  (P-l)(P-3)(G-4)(G-6)(G-7)(G-9)

    -If natural flushing is permitted, EPA should require monitoring
     of the ground water for the entire flushing period  to verify
     underlying assumptions.  (G-9)

    -Lack of a specific minimum monitoring period could  lead  to
     controversy among the implementing agencies.   A monitoring  period
     of several decades will be necessary to confirm the  operation of
     new disposal cells since construction will be  based  on  a design
     rather than performance standards.  Also, post-disposal
     monitoring should always be co-extensive with  any extended
     remedial period to confirm projections  of computer  simulations
     and prevalent expert judgment.  Confirmation monitoring  will  be
     nece.ssary at both disposal and processing sites;  this should  be
     consistent with RCRA, 30 years.

     Use of site-specific conditions to determine length  of
     post-disposal ground-water monitoring is similar  to  what the  10th
     Circuit Court struck down.  (G-7)
   . -The need for post-disposal ground-water monitoring  will' depend on
     the site management strategy.  Where completely dry  tailings  are
     moved to a lined and capped facility and all contaminated ground
     water is removed and treated, a short period (e.g.  15 years)
     might be appropriate.  Because of the record of liner and
     containment breaches at RCRA and  other  disposal facilities,
     monitoring is believed imperative.  If  the clean-up  strategy  is
     natural flushing, monitoring should be  for at  least  the  100 years
     at the end of which the natural flushing is supposed to  achieve
     compliance.  This is necessary because  the inexact  nature of
     current state-of-the-art modeling, which 'forms the  basis for  the
     natural flushing assumptions.   (P-l)


    -The notion that monitoring can  last  up  to  100 years  is  rejected,
     and any post-closure monitoring  should  be  conducted  prior  to
     NRC's site licensing.  It is  noted  that  legislation  may  be
     required to permit approval of  monitoring  plans  of 10 to  15
     years; the present statute would  not  permit  monitoring  past
     1990.  The use of active, engineered'ground-water  restoration
     techniques should alleviate the  need  for extensive post-closure
     monitoring.   (P-3)


     The regulations currently require that  DOE maintain  monitoring  of
the closed site for a period of time  comparable to the  time period
required under  § 264.117 for waste sites  regulated under  RCRA  (i.e.,
30 years).  The exact period of time  post-closure monitoring  is
required has been  left to the DOE  to  determine, with  NRC  concurrence.
EPA believes that  this is the most reasonable solution  and is  in
keeping with the requirement that  these  regulations be  consistent  with
RCRA regulations.
     In instances  where DOE has chosen to  extend  the  remedial  period
to allow natural flushing, the regulations require that the progress
of the flushing be monitored throughout  the  extended  remedial  p.e.riod.
In this case, post-closure monitoring  would  not begin until  the
extended remedial  period expires.  In  this example, monitoring  would
be required for as long as 130 years  if  EPA  required  a  specific
30-year post-closure monitoring period.   EPA believes that this would
be unreasonable.
     The Tenth  Circuit Court of Appeals  remanded  the  ground-water
provisions of the  original regulation  because the regulation  did  not
contain specific numerical standards  for  the protection of ground
water.  Neither the remanded provisions  nor  the Court mentioned any
requirements for specific time periods.   EPA believes that these
regulations meet the requirement for  consistency  with RCRA.

Question 10.  For  tailings regulated  by  NRC  under Title II of  the
Act/ section 84(a)(3) requires NRC to  develop regulations to  conform
to general requirements applicable to  the  possession, transfer, and
disposal of hazardous materials regulated  by the  Administrator.
Should the standards proposed here incorporate  such requirements  for
tailings regulated under Title I?

Several reviewers  found this question  ambiguous or challenged  EPA's

    -Since the  subject EPA provisions  are  still being refined  and
     the requirements that will apply  to  the Title II sites have  not
     been fully evaluated, incorporating  these  for Title  I sites  may
     be premature.  The requirements  as  to financial  assurances and
     cradle-to-grave manifests and transportation are examples  of  EPA
     requirements  that are not needed.   The  proposed  rule includes a
     reasonable level of detail for  implementation.   (G-2)


    -NRC's authority has not been  characterized  with  precision;  NRC's
     obligation is to develop  regulations which  are,  to  the  maximum
     extent practicable, at least  comparable  to  requirements
     applicable to the possession, transfer,  and disposal  of similar
     hazardous material regulated  under  SWDA.  When EPA  adopts
     standards for mining wastes, and when NRC issues  comparable
     regulations for tailings, then such requirements may  be
     incorporated for Title I  sites without objection.   (1-5)

    -The question is poorly drafted.   If EPA  is  asking should  the
     standards for UMTRA sites be  RCRA-consistent in  the same  manner
     as standards for active uranium mill sites, the  answer  is
     affirmative.  EPA should  adopt standards containing provisions
     that parallel all relevant  RCRA rules; these should be  consistent
     for active and inactive sites.  However,  the question appears to
     ask whether EPA should require NRC  to conform its regulations to
     EPA's UMTRAP standards; there is  no statutory requirement for
     this so long as EPA's standards are directly implemented  at all
     UMTRAP sites.  (P-l)

    -The question is ambiguous.  These standards should  conform  with
     EPA's SWDA standards for  materials  posing similar hazards ,b,ut NRC.
     should not be required to undertake further rulemaking.   There
     are a small number of inactive sites, the remedial  program  is
     underway, and cleanup is  the  responsibility of the  government.
     Another layer of regulatory requirements is unnecessary.  (1-4)

Such additional requirements are unnecessary.  (G-7)(G-8)

    -DOE,  with NRC oversight,  has  accepted environmental protection
     responsibilities for Title  I  sites  and developed procedures for
     possession,' transfer, and disposal  of tailings and  other
     contaminated materials.   DOE  and  its contractors are  bound  by
     applicable Federal and State  regulations in the  handling  of any
     wastes not contaminated by  the milling process.   At the Title I
     Canonsburg and Ambrosia Lake  sites, for  example,  DOE  and  its
     contractors worked successfully with applicable  State agencies to
     ensure "full compliance with regulations.  (G-8)

    -The purpose "of remediation  or decommissioning is to make  the land
     suitable for uncontrolled release.  If the  site  is  not  suitable
     for uncontrolled release, then adequate  remediation has not been
     accomplished and the existing standards  for possession,  transfer
     and disposal of hazardous materials are  sufficient.   (G-7)

Requirements 'for Title I tailings  are  supported.  (P-3)(G-4)(G-6)(G-9)

    -There is. no difference in health  threats between Title  I  and
     Title II tailings and there should  be the same responsibility to
     assure a safe and clean environment regardless of the entities
     providing the cleanup.  (G-4)(G-9)

    -The standards for ground-water protection at Title  I  sites  must
     be consistent with those  for  Title  II sites.   (P-3)



     EPA agrees that requiring NRC to develop  additional  regulations
for Title I sites governing the possession,  transfer',  and  disposal  of
hazardous materials regulated by the Administrator  is  premature  and
not necessary under these regulations.  There  are only 24  Title  I
sites and there are no active operations at  any  of  them.   Also  the
sites are being remediated under government  control  and will  remain in
government control upon completion of the  remediation.  DOE has
demonstrated that they can responsibly implement EPA regulations
without additional regulation.

Question 11.  Is it appropriate to base the  uranium  contaminant  limit
on radioactivity alone or should the chemical  toxicity of  uranium
result in a more restrictive value?

The proposed radioactivity concentration limit of 30 pCi/1 will
protect against possible kidney damage associated with drinking  water
that contains uranium and this limit is supported.   (G-7)

All other reviewers supported consideration  of the chemical toxicity
as a basis for the uranium contaminant limit but several  expressed
differing views as to what the limit should  be.

Both chemical and radiometric toxicity should  be considered and  the
more conservative limit selected.  (G-2)(G-4)(G-5)(G-9)

    -A limit based on chemical toxicity would  not result  in a lower
     limit than the one proposed.  (G-2)

The National Academy of Science's "Suggested No  Adverse Response
Level" of 0.035 mg/1 should be used as the limit, corresponding
roughly to 23 pCi/1.  (G-6)(P-l)(P-3)

However, a limit of 0.1 mg/1 as suggested  by Cotter  Corporation  at  the
Public Hearing would not be objected to.   (G-6)

    -The recommended uranium limit would not only address  the greater
     chemical hazard but would reduce analytical costs since  typical
     laboratory costs for total uranium analysis are one-fourth  to
     one-sixth those for individual uranium  isotopes.   (P-3)

The uranium limit for ground water should  be based on  chemical
toxicity alone.  (1-2) (1-4) (1-5.)

    -EPA has established its uranium limit to  protect  against
     stochastic effects (cancer) using the limits recommended for
     nonstochastic effects (threshold effects).  Based on  the
     recommendations of the National Workshop  on Radioactivity  in
     Drinking Water, convened by EPA in May  1983, for  a limit of
     100 ug/1 (based on safety factor of 50-150), the  proposed  limit
     should be stated in mass rather than  radiological  units  and a
     limit of 1-2 mg/1 would be well below the likely  threshold  level
     at which any concern for chemical toxicity  would  exist.  (1-5)


    -Also referencing the NAS study, a limit of 0.1 mg/1  is
     recommended.  (1-2)

   -It is arguable that no limit is even warranted but,  in any  event,
     any limit should be far less stringent than that proposed.   (1-4)

EPA may wish to consider the chemotoxicity of  uranium in  the final
standards.  The proposed standard of 30 pCi/1  based on radiotoxicity •
is 10 pCi/1 lower than the EPA upper value of  the 'adjusted acceptable
daily intake corresponding to 40 pCi/1 based on limited chemotoxicity
data.  (G-8)


     The Agency has revisited the uranium standard and .has concluded
that it should consider chemical toxicity of uranium as well as  the
radiotoxicity.  In developing the proposed standard, the  Agency  used
nonstochastic dose conversion values for uranium instead  of the  more
appropriate stochastic values and did not consider the cost
implications of achieving a risk level equivalent to that of the
standard for radium.
     EPA is in the process of examining these  factors, but will_npt
reach a decision on the MCL for drinking water before this standard is
promulgated.  However, the standard-setting process has proceeded far
enough to determine that the MCL for uranium in drinking  water will be
close to the limit that was proposed and is promulgated in this
regulation.  Should the MCL as finally promulgated be different  from
the limit in this regulation, EPA will reconsider the limit at  that
time.  On the basis of these considerations, the standard for uranium
has been established at 30 pCi/liber for this  regulation.
     EPA will consider the National Academy of Science's  "suggested no
adverse response level" of 35 ug/1 when deriving the maximum
concentration limit for drinking water.

Question 12.  Should the Agency consider revising the Title II
regulations to incorporate those portions of Title I regulations that
are different from the Title II regulations, e.g. the additional
contaminant limits in Table A?

The Title II regulations should not be revised for consistency with
the proposed Title I rules.  (P-3)(G-l)(G-8)(1-3)

    -There is concern that any such revisions  in Title II regulations
     not affect current agreements regarding commingling  of Title I
     and Title II tailings in Wyoming and South Dakota.   (G-8)

    -Any change which would make the standards more restrictive,  for
     Title I or Title II sites, is entirely unjustified.  (1-3)

    -If EPA adopts a liner requirement at Title I sites consistent
     with Title II requirements and abandons proposed institutional
     controls, the only differences will be the concentration limits
     for uranium, molybdenum and nitrate.  NRC could consider adding
     these limits to its regulations if pending litigation over  NRC's


     active-site ground-water requirements necessitates new
     rulemaking.  (P-3)

Revision of the Title II regulations to incorporate various features
of the the proposed Title I rules is supported.   (P-l)(G-2)(G-4)(G-7)

Revising Title II rules to include the flexibility provided by
proposed Title I standards is favored.  (G-2)(1-2)(1-4)(1-5)

    -Many of the current Title II decommissioning efforts at existing
     sites are similar to Title I remediation  in  that  the tailings
     were generated before standards were established  and there  may
     not have been any significant milling operations  for years.
     Values and rationale for the additional  constituents could  be
     factored into Title II ACL decisions without a rule change.   (G-2)

    -The differences in operational status between Title I (inactive)
     and Title II (active) sites will warrant  some differences in  the
     operating standards.  The Title II sites  are licensed; the
     presence of a responsible party subject  to continuing regulatory
     oversight assures interim steps can be taken prior to final...
     reclamation and decommissioning to contain or reduce potential
     ground-water impacts.  The standards adopted for  the active sites
     are not appropriate for the type of waste involved, high volume
     and low toxicity, or the nature and extent of hazards posed.

    -Several comparisons have been made between the Title I and  Title
     II regulations, and the proposed regulations should be amended to
     apply to active as well ,as inactive sites.   (1-2)

    -It is recognized that natural flushing can be adequate to restore
     contaminated ground water and will allow  the exercise of judgment
     on a site-specific basis as Title I features that should be
     included in Title II.  The time is ripe  for  a total
     re-examination of EPA's mill tailings 'regulatory  program.   (1-4)

Inclusion of the additional contaminant limits in'Title II regulations
is favored.  (P-l)(G-7)(G-9)

    -Licensed Title II sites are subject to NRC and Agreement State
     regulation and it .is anticipated that the current federal NIPDW
     regulations and State standards would be  utilized for making
     Title II decisions until the National Interim and Final Primary •
     Drinking Water Regulations are established for all constituents
     of concern.  (G-7)

    -Consistent with the mandate of UMTRCA, those deficiencies
     representing an endangerment to human health and  the environment
     should be incorporated into Title II regulations.  The prompt
     identification and regulation of toxic constituents now will
     minimize or potentially eliminate a need  for costly aquifer
     remediation at some future date.  (G-9)



     The Agency was considering  revising Title  II  regulations  to
incorporate some of additions in the Title  I  regulations.  However,
the American Mining Congress has requested  that  the Title II
regulations be submitted to a negotiated rulemaking.  Therefore, until
the request for the negotiated rulemaking  is  resolved, the Agency will
not proceed further regarding the Title II  regulations.

Question 13.  Are the estimated  costs of implementing these proposed
standards accurate and based on  reasonable  assumptions?

The EPA estimated costs are considered to  be  reasonable, based on
knowledge and experience at Tuba City and  on  the Navajo lands.

Although the bases for the EPA estimates of costs  were not reviewed,  a
comparison between these projected costs at the  24 sites and DOE's
estimate of total UMTRA Program  costs was  made.  Based on EPA's
estimate of $12 million per site, the cost  of implementing the
ground-water standards would be  $288 million  based on use of   .„..
institutional controls, possibly $400 million without the proposed
institutional controls.  Thus, ground-water restoration at Title I
sites would account for 30 to 50 percent of the  $1 billion estimated
by DOE as total UMTRA Program costs.  These costs  were felt to be
reasonable and proportional to the health  and environmental benefits
derived from aquifer restoration.  (P-3)

EPA's cost estimates are probably too low.  (G-7MG-8)

    -The estimates were based on overly simple  assumptions and on
     limited data and many items were omitted from the cost
     estimates.  Also, the BID considered  information from only  12 of
     the 24 sites; one of the omitted sites,  Falls City, has an
     inordinately high restoration cost because  of plume size  and
     contaminant concentration.  DOE estimated  aquifer restoration
     costs at five sites - Gunnison, Riverton,  Lakeview, Tuba  City and
     Falls City - using the Random Walk Algorithm  (Illinois State
     Water Survey, 1981) based on various  ground-water treatment
     options.  Costs from these  5 site-specific  evaluations were then
     extrapolated to the'remaining 19 UMTRA Project sites based  on
     similarities of cost-controlling factors.   For the 12 sites for
     which EPA estimated total costs of $154  million under most
     probable scenario, DOE estimated aquifer restoration costs  of
     $628 million.  Post-disposal monitoring  for a projected 30 years
     would cost an additional $45.82 million  (reference attached
     material).  (G-8)

    -Based on the commenter's review and interviews with several
     ground-water experts, the estimates could  be  low by a factor of
     10 to 100%.  (G-7)


Because of the large discrepancy between cost  estimates  made  by  EPA
and those by DOE, it is recommended  that a  more  comprehensive  analysis
of remedial action costs be made.   (1-2)(1-4)

    -The commenter was unable to evaluate the  EPA  estimates because  of
     the lack of documentation or references,  and  some apparent  errors
     or inconsistencies in the calculations.   (1-2)

No comment is made on the specific cost estimates  presented but
long-term monitoring costs, incremental costs  of ground-water
protection at new disposal sites, and costs of coverage  at vicinity
properties (if coverage of these is  intended by  EPA)  should be
addressed.  (G-2)


     EPA has received new cost information  from  DOE  and  finds  that the
new information is reasonably close  to the  EPA cost  information.  EPA
has incorporated this new information into  Chapter 6  of  the BID  and
summarized it for the regulations.   The new information  indicates that
EPA's original estimates were close  to the  final estimated costs.

Question 14.  What criteria should be used  to  judge  "technically
impracticable from an engineering perspective"?  Can  and should  these
criteria be specified in the rule or should they be  left to the
judgment of the DOE and NRC?

Criteria either could not or should  not be  identified.   (P-3HG-2)

This determination should be left to DOE and NRC.   (G-2)(G-4)(G-6)(1-4)

The determination should be with State and  tribal  concurrence.

    -The apparent EPA interpretation of impracticable doesn't  leave
     any room for interpretive criteria.  Also,  there will be
     opportunities for public input  to the  decision  through the  NEPA
     review and cooperative agreements with States and tribes.   (G-2)

    -Specific criteria are not possible because  of the variability of
     sites and EPA should not delegate its  mandated  responsibility in
     this regard.  (G-9)

    -The determination as to the applicability of  supplemental
     standards should be based on comparison of  the  risks to public
     health and the environment and  the cost of  various  remediation
     alternatives.  These would be site-specific determinations, best
     left to DOE with NRC concurrence.  (1-5)

    -Elevating unenforcable guidelines to the status  of  legally
     binding regulations and supported substitution  of "technically
     possible" for "technically impracticable from an engineering
     perspective" is opposed (see comment by P-l).   (P-3)


EPA should develop criteria, rather  than  leaving  this  responsibility
to the discretion of DOE and NRG.  However,  no  suggestions  as  to
specific criteria were provided.   (P-l)(G-7)

    -EPA should develop both specific criteria  and  guidance  documents
     and/or procedures for use  in  the decision  as  to what  is
     technically impracticable  from  an engineering  perspective.   Also,
     such decisions should be subject to  State  and  tribal
     concurrence.  (G-7)

    -Use of the term "technically  possible"  instead of  "technically
     impracticable from an engineering perspective" is  suggested;  this
     would be clear enough that a  list of complex  criteria  would  not
     be needed to elucidate its meaning.  Criteria  should  be
     articulated in the rule to fulfill EPA's responsibility to
     promulgate specific regulations for  the cleanup and prevention of
     ground-water contamination as directed  by  the  Appeals  Court.

The concept of technical impracticability is a  recent  development  and
has not yet been applied in remediation;  application of this concept
should be left to the judgment  of  DOE and NRC.  If  EPA  decides _ko .
specify criteria in the final standards,  DOE would  like to  review  the
criteria prior to promulgation.  If  the supplemental standard  of
technical impracticability is applied on  a case-by-case basis, the DOE
would develop extensive documentation, including an evaluation of  the
degree to which remediation is  possible,  and then  consider  the costs
and benefits.  The onus would be on  DOE to identify cases  of technical
impracticability and to argue for  the application  of this  concept  at
specific UMTRA Project sites.   DOE recommends that' the  following
criteria be included at a minimum:

     - absence of technology to achieve the  desired goals  (i.e. MCLs)
     - no methods available to  achieve these goals  within  the  bounds
       of financial resources or the schedules  over which  such work
       can be controlled,
     - two or more mutually exclusive technical criteria,  rules,  or

The DOE believes that, if technical  impracticability is found  to
exist,  an evaluation should be  undertaken to apply  controls  or conduct
a partial cleanup in an attempt to meet the  standards  with
consideration of the costs incurred  for the  benefits achieved.  (G-8)


     EPA discussed the general  meaning of "impracticability"' in the
preamble to the proposed rule and  this has not changed.  In  the
preamble to the proposed Subpart S of RCRA,  EPA has addressed
"technically impracticable" as  it  applies to RCRA  facilities.  When
"technical impracticability" is implemented  in  that rule,  the Regional
Administrator reserves the right to  require  remediation to  levels
which are technically practicable  and which  significantly  reduce
threats to human health and the environment.   EPA  provides  this
information as guidance to the  implementing  agencies, but  will not


impose any specific criteria for judging  "technically  impracticable
from an engineering perspective" on the implementing agencies.

Question 15.  The criteria proposed here  to specify ground water  as
Class III; and therefore qualified for supplemental standards, are
based on draft proposals still under consideration by  the Agency.  Are
these criteria appropriate for this application, or would others  be
more appropriate for use at these sites?

The proposed Class III criteria are appropriate.   (G-4HG-6)

Provided the ground water will not have the potential  to contaminate
other classes of water for the next 1000  years.  (G-4)

The inclusion of draft classification criteria  in  the  final  standards
is rejected.  (P-l)(G-2)(1-4)

    -NRC has^identified several significant limitations in the
     ground-water classification system and its implementation as
     proposed by EPA in December 1986 and these concerns also applied
     to implementation as part of the proposed  standards for
     ground-water protection at the UMTRAP sites.  (G-2)

    -The Agency should take a broad historic perspective in  regard to
     the threshold criteria, that the ground water not be a  current or
     potential source of drinking water,  noting that it is extremely
     difficult to predict future population migrations and
     concentrations in this country.  EPA should,  instead, assume that
     all ground water in the West is a potential water supply source.
     No technical support for the 10,000  mg/1 limit is known, and this
     criteria should also be dropped.  Limiting the treatability
     criteria.by tying it to public water supply system technology is
     questioned.  Instead, the DOE should be required  to select from
     the current universe of cost-effective technologies such as
     supercritical fluid oxidation, reduction,  extraction (heating
     and/or freezing), separation, chemical detoxification (thermal),
     biological detoxification, binding,  ozonization,  and any in  situ
     decontamination technologies.  The 150 gpd yield  criteria is
     considered irrelevant and should be  deleted.  (?-l)

It is entirely improper to introduce the  concept of Class III ground
water into these standards since there-is an insufficient technical
basis given for their inclusion and any standards  to be applied for
ground water should be consistent with applicable  State standards.  By
using a ground-water classification standard in these  regulations, EPA
is ignoring the State's role and allowing the DOE  to determine land
use through ground-water classification which has  not  been previously
adopted by federal rulemaking procedures.  (G-7)

A special class of ground water should be defined  specifically for the
UMTRA Project.  Criteria for including ground water in this  class
would be:  widespread ambient contamination that cannot be cleaned up
using treatment- methods reasonably employed in  public  water  supply
systems, or well yields of less that 150  gallons per day, or a total


dissolved  solids  threshold  concentration  limit  that  is  lower than the
present  10,000 mg/1.   (G-8)

As an  alternative  EPA  could  specify  a process  by  which  human 'health  .
and  the  environment  would be  protected and  aquifer  restoration may be
minimized.   Class  III  ground  waters  are not a  potential source of
drinking water and  are  of limited  use.   It  is  clear  that the intent in
including  Class  III  ground  water  is  to avoid or minimize restoration
while  protecting  human  health and  the environment through avoidance of
use.   Such an  evaluative process  could be performed  for UMTRA Project
sites  that overlie  Class II  waters.   Should analysis at a specific
site demonstrate  to  NRC's satisfaction that complete restoration is
unnecessary to protect  long-term  human health  and the environment,
then partial or  no  restoration would occur.  (G-8)

Supplemental standards  are  appropriate where the  affected ground water
is Class III but  should also  be available for  Class  II  gro.und water •
under  the  Guidelines on a site-specific basis  where  protection of
human  health and  the environment  can be reasonably  assured.   Factors
to be  considered  in  allowing  supplemental standards  where the affected
ground water is  Class  II should include:   quality of the water,  source
of the water,  quantity  of the water, availability of alternate .sources
of water,  actual  and reasonably probable  use of the  water,  nature and
extent of  contamination, costs of  remedial  action,  potential for human
exposure and detrimental environmental effects.  (1-5)


     The regulation  has been  modified to  protect  all beneficial uses.
The  term "Class  III" has been changed to  "limited use"  to better
reflect  the intention  of EPA  in identifying this  supplemental standard
     EPA recognizes  that identifying certain ground  waters  as elegible
for  supplemental  standards  does not  provide explicitly  for  recognition
of State ground-water  classification schemes.   -However, the
regulations do  recognize special  situations in which normally unuseful
waters may require  protection, and in any case, the  supplemental
standards  require  selection  and performance of remedial actions that
"...come as close  to meeting  the  otherwise  applicable standard as is
reasonable under  the circumstances."  EPA decided that  the. only
equitable  method  was to distinguish  limited use ground  water in the
standard.   The  relationship of the States to the  implementing agencies
'is described in  UMTRCA, and  States should refer to  the  Act  in
determining how  they may interact  with the  implementing agencies.
     Class II  ground waters  do not qualify  for this  supplemental
standard because  of  their potential  for use in the  future.
Supplemental standards  other  than  the "limited use"  standard are
available  for  waters that meet the criteria for Class II if  the
"relevant conditions  apply.