Uiriilind Statins
                              Environmental Protection
                               Offfca of
                               Solid Waste and
                               Emergency Response
             Directive:  9355.0-27FS

                            ril 1990
         ft EPA
A  Guide to  Selecting
Superfund  Remedial Actions
  Office of lE:inHEi(i;^»n:!|i..iiii»[|.Ji(• n npipropriitto niro
                                 Cantaiin.mp.nit will !»r vanmdenet for maa&ea fJiat ;:>:mr a nlatively
                                 law !«(i,!f-it(:r-rri threat or wherv treatment ui impmctK-abit . Thttoe
                                 includii!! wmitisn (.lui.t nuw n«w haiiltli~b«[iii»cl krraln,, ure nutHitiin-
                                 ItiniUy iiauDaobiLli!, or citlioirwiiiie CUM \w irnllinbly oaiitiiin«d over \oag
                                 piiruxlji eiftimo; wfinbtmi thill; iur« tochnkniliy diflk-ult to tritnt 01-
                                 for wliiilch ltn)n.l:i]3M)i)K u inleiuiiUa ac uiiiiivnilnjbl«; iiitunltiaoii
                                 where (:r(!n);i]]>!!i]1t-lc»nni!nn, wlntiliiKiitiaa, or other
                                 niiiieriinlii ItiaiJiclJJinjj; prabliMgctn; oir niton thnt «:r« iHtt.nionli ruiiily
                                 la]'ij« where the ncope lafthe pirobleign nauny mnlde tirenlnrient of nil
                                 wiuiben ingipnictlcflJble, nuch mi irnuinidpnil  liuridfillii or
    •  ,A:reiin oDiiitairniiuitocl with high noDoenirnltiaiCLn of toxic com-

    •  Ljqu'idn uikl oitber UjtfMy iBabili! icniiitairinl»;;

    -    niKKlin (».)!;,,  caaUimnuitod gixnuadi ntnllnr,
      :i«Ehdijt[ii!iiit1t noil) Ithnl: \xaw m^inttauit irimk aliiiqionnm; air
      M»dii> oointniiumij; nantainhinntii noiwinl oirdhEin
                                            control® aim motit uaefU aa a ituftplimunt to ttngi-
                                 nttringeontnU/brtltort- aadlonff-termmamagemjent. Iniititu-
                                 itiotuill contnlii (e.([. dnnd, nBumridtianaii, prahiiliiitioirui of w«ll con-
                                 .i*riji«tk iin) ijonpaitefil; in mnltrolliiig i!«pcmiuiri!« iliuirinfi irnme-
                                 dial iKitknii iLngiipl«>inieicrbn1.ioni nnd nn m nupptiinmiKnt to ]bn|g;-te:fini
                                 'En(j-Lni! Appropruiti nmadiaa mftxn will exmbim treatment and con-
    iainmmt.  F'ac 11 iipendlic itifce, itrentaMMit  of l.lie prwciipunl
    tlu«!iKUii) mny bi) minbinecl with ranitaiiucncnt of treniineiiit
    raiiidniiLln iiinil low-lew! caiaUuninnb»d cniiteiriiil.
                                           t»icfwu)ii\ywa Amid be amuidnrtd if tJwy offer the
                                 potential for mmattmbla w nifwriw ininimunt parfiormancK,
                                 /(' U'cf/Jirmicrr adtwmf imf>af.f.n, tw louxar coot® for itimiilar le.vf.it of
                                 per formanee than demonatmtad Mc.A.na^ijw'n.

                              >• Ground wateni will be returned to their lttneficia.1 uaen within
                                 reaaonabk perioda of time wh
                                                                                                      April 1990 -

                               Exhibit 2
              Kay SUqpo in thin Dowlopmmnl of llnniiiiilnl Alternative*
       OiiviitQp Prtiimmiwy HorniMJiiutNW (loilhl
             HimJih-taiitiidi H»rm«iiiEtii»« igwiM )«,([.,. IO^UKCIMMI eanew imitt ti
             poimi ol jLrtur«. ARAflu: MMnuiltingi in X pprn
                             OHorrrmo .IU'IIM
                             ttui iiK|iinni ritrriiMJiiill iiciJori
       Wwniiif)' P'rinciiMUl Thf««i« tKiM am Cjirtalirtiiinu four Tiwihrriiut

       •  Troitfl l«iu«hi. t\iq\My loi
                               kjuicflMii. iirikiii ««*M»rn cMmuiiiiinxiriBii
       ktanrtity low-towi! 'UliiiMitii Ittllt iiw CjifKlriutlMi tw CcMnMitfMnniirvl
       CcNnitJitn TrimtrrMixM

                      I'oniiJP, Tnun

                      • TinlMt to ItowrtW tllfll cal/1
           1=1% Truit

           • TriMt la HviJ«i tor

demon strate that statutory require-
ments have been  satisfied (Sec.
300.43(XfXD).  Each of these as-
pects of EPA's remedy  selection
approach are described below,

    The national goal of the remedy
selection process is "to select reme-
dies that are  protective of human
health and the environment, that
mainbEiin protection over time, and
thai: minimise untreated  waste"
(NCP Sec. 300.43

       EPA has developed nine criteria to
  be used to evaluate remedial alterna-
  tives to ensure: all important considera-
  tions are factored into remedy selection
  decisions.  These criteria lire  derived
  from the statutory requirements of
  Section 121, particularly the long-term
  cflecttyeness and related CDnsi derations
  speciffedinbSection 121(bXl), as well as
  other additional technical and policy
  considerationa Unit have proven to be
  important for selecting among re medial
  alte rnatives.

  Threshold Criteria

       The two most important  criteria
  are statutory requirements  that must
  be satisfied by any alternative in order
  for it to 1>E! eligible for Mlection.

  1.   Overall protection of human health
       and that environment  addresBei
       whether or not a remedy provides
       adequate protect ion Bind describes
       how riska poaed  through  each
       exposu re path way (asau nni ng a. rea-
       sonable maximum exposure) are
       eliminated, reduced, or controlled
       throu |j;h treat merit,  engi neeri ng
       controls, or institutional coatrola.

  2.   Compliance with applicable or rele-
       vant andappropriate requirements
       (ARARn) addrenaen whether a rem-
       edy will meet all of the  applicable
    or relevant and appropriate require-
    ments of other Federal and State
    environmental laws or whether a
    waiver can be justified.
    Five primary balancing criteria are
used to identify major trade-offs between
remedial alternatives. These trade-off*
are ultimately balanced to identify the
preferred alternative and to select the final

1.  Long-term   tffecliven«s»   and
    permanence refers to the ability of n
    remedy Ui maintain reliable protec-
    tion of human health and the envi-
    ronment over time, once cleanup goals
    have been met.

'!..  Reduction of' toxicity, mobility,  or
    volume through treatment in the an-
    ticipated performance of the treat-
    ment  technologies a remedy may

3.  Short-term effectiveness addresses the
    period of time needed to achieve pro-
    tection and any advene  impacta on
    human health and the environment
    that, may  be posed during the con-
    struction and implementation period,
    until cleanup goals are achieved.

4.  Implementability  in the technical and
    administrative feasibility of «. rem-
    edy, including the availability of ma-
    terials arid services needed to imple-
    ment a particular option.
5.  Coat included estimated capital and
    operation and maintenance• costs, and
    net present worth costs.

Modifying Criteria

    Them: criteria may not be considered
fully until aflerthe formalpubliccorrunent
period on the Proposed .'Ran and RJ/F'S
report in complete, although EPA  worka
with the State and community throughout
the project.

1.  Staff, acceptance addresses the imp-
    part agency's comment*. Where the
    State or other Federal agency is the
    lend agency, EPA't acceptance of'the
    •elected remedy should be uddreaaed
    under thin criterion. State views on
    compliance with State  ARARs are
    especially important.

'.I.  Community acceptance refers to the
    public's general response to the alter-
    natives deflcrribed i in the Pro poned PI an
    and the HI/FS report.

     The 1990 NCP at 55 FR S21SLZ3.
describes how the detailed analysis of al-
ternatives in to be performed using these
criteria.. The deta.filed analysis is the infor-
mation bane upon which the remedy nelcc
tic in dominion in made.  Chapter 7 of the
"Interim Final Guidance for Conducting
Remedial Investigations and Feasibility
Studied Under CERCLA" (October 1988)
provides flirt her detail on the process.
issued for comment along with the
RI/FS.  Upon receipt of public com-
ments on the Proposed Plan, the
lead agency consults with the sup-
port; agency to determine if the pre-
ferred alternative remains the most
appropriate remedial action for the
site or operable unit.   The  final
remedy is selected and documented
in a Record of Decision.

Considering thiE! Nine Criteria

    The identification of a preferred
alternative and final selection of a
remedy is derived from considera-
tion of nine evaluation  criteria in
three major steps, as  described in
the      1990     NCP     (Sec.
300.430(0(D(ii)(E)J.  The nine crite-
ria are presented in  Exhibit  3. The
steps in which the criteria are con-
sidered are depicted in  Exhibit 4
and discussed below,
Threshold Criteria

    The first step of remedy selec-
tion is to identify those alternatives
that satisfy the threshold criteria.
Only those alternatives that pro-
vide adequate protection of human
health  and the environment and
comply  with  ARARs  (or justify a
waiver) are eligible for selection.
Alternatives that do not satisfy the
threshold  criteria should not  be
evaluated further.

Primary Balancin g Criteria

    The second step  involves the
balancing; of tradeoffs among pro-
tective  and ARAR-compliant alter-
natives with respect to the five pri-
mary balancing; criteria  (and modi-
lying criteria,  if known).  In this
step, alternativesare compared with
each other based on their long-term
effectiveness  and  permanence, re-
duction in toxicity, mobility, or vol-
ume  achieved through treatment,
implementability, short-term effec-
tiveness, and cost. The sequence in
which the criteria are generally con-
sidered, and pertinent considera-
tions related to each, are noted be-

1.  Long-term,  effectiveness   and
    permanence is a major theme of
    CERCLA Section  121,  and,
    therefore, is one of the two most
    important criteria used during
    remedy selection  to determine
    the maximum extent to 'which
    permanence and treatment are
    practicable.    This factor  will
    often be decisive where alterna-
    tives vary significantly in the
    types  of residuals  that  will
    remain  onsite and/or their re-
    spective long-term management
                                                                                                     Apr U 1990-3

                              Exhibit 4
        cirri: FIIA
                          from Screening,
                         EtouiJ an Program
                        Long-term Effectiveness
                        Reduction of T.M.V.
                        Short-term Effectiveness
                      CliooiM) Preferred Alternative:
                      •• Ejalancing attorn Critnrin
                      •• Emphasize Long-Term
                        Effectiveness am) Reduction ol
Proposed Ran IUUBNJ tor Comment

Stat» mi


Selected Remedy
2.   Reduction in the tenacity, mobil-
    ity, or volume of contaminants
    achieved through the applica-
    tion of treatment technologies
    is the other criterion that will
    be emphasised during remedy
    selection in determining the
    maximum extent to which per-
    manent solutions and treatment
    are practicable.  Remedies that
    use treatment to address mate-
    rials  comprising the principal
    threats posed by a site are pre-
    ferred over those that, do not.
    Treatment as part of CEECLA
    r e m ed ii e a   s h ou I til  g
                                            Exhibit 5
                   Relationship of the Nine Criteria to the Statutory Findings
                          IMIitlE CRITERIA
                 AMD THE ENVIRONMENT
                    ••>•• PROTECTION OF HUMAN HEALTH
                        AMD TOE! ENVIRONMENT
                 COMPLIANCE WITH ARARs
                  AND PERMANENCE

                  TOXICITY. MOBILITY. OR
                  VOLUME REDUCTION
                  THROUGH TREATMENT

                  STATE AGENCY ACCEPTANCE;
                  COMMUNITY ACCEPTANCE
                        COMPLIANCE WITH ARARs OR
                        JUSTIFICATION OF A 'WAIVER
                        UTILIZATION OF PERMANENT
                        SOLUTIONS AMD TREATMENT OR
                        RECOVERY TO THE MAXIMUM
                        EXTENT PRACTICABLE f'MEP")
                                                          PREFERENCE FOR TREATMENT
                                                          AS A PRINCIPAL ELEMENT OR
                                                          EXPLANATION AS TO WHY
                                                          PREFERENCE NOT SATISFIED
Identification of a Preferred

    Once the relative performance
of the protective and ARAR-compli-
ant al.ternatives under each crite-
rion has been established, prelimi-
nary determinations> of which op-
tions an cost-effective und which
alternatives utilize  permanent so-
lutions and treatment technologies
to the maximum extent practicable
are made to identify the preferred
alternative.  Exhibit 5 illustrates
the relationship between the nine
criteria and the  statutory require-
ments for remedy selection.

    Cost-effectiveness is determined
by comparing; the costs of all alter-
natives being considered with their
overall effectiveness to determine
whether the costs are proportional
to the effectiveness achieved. Over-
all (effectiveness  for  the purpose of
this  determination include!) long-
term effectiveness and permanence;
reduction of toxicity, mobility, and
volume  'through treatment;  and
short-term effectiveness. Home than
one alternative can be cost-effec-

   The determination of which cost-
effective alternative utilizes perma-
nent solutions and treatment to the
maximum extent practicable is a
risk management judgment made
by the decision maker who balances
the tradeoffs  among; the alterna-
tive® with respect to the balancing;
criteria (and modifying; criteria to
the extent they are known). As a
general rule, those criteria that dis-
tinguish the alternatives  the most
wiill be the most; decisive factors in
the balancing.  See Exhibit 6 for at
summary of criteria likely to be im-
portant in certain site situations.
The alternative determined to pro-
          vide the best balance of trade-off'!;,
          as considered in light of the statu-
          tory mandates and. preferences, as
          well as the NCP goal and expecta-
          tions,, is identified as the preferred
          alternative and presented to the
          public for comment in a Proposed

          Final Selection of Remedy

             Upon receipt of public  com-
          ments, the preferred alternative is
          reevaluated in light of any new in-
          formation that, lias become avail-
          able, including; State and commu-
          nity acceptance, if previously un-
          known. This new information should
          be considered to determine whether
          an option other than the preferred
          alternative better fulfills the statu-
          tory requirements.  The decision-
          maker's final judgmen (; is docu-
          mented in a Record of Decision.
                                                                                      April 1990 - 5

                                                               Exhibit l:i
                                                 FOR SELECTED SITE SITUATIONS
  Small iiren of high level* of toxic coiitaniinant.ii
  (e.g., lagoon, hot npcrtji)
  Highly mobile contaminant* (e.g., I iqiaidn, vo In-
  lik-n, metal*)
 Very large volunw of material contaminated
 maronaUy above health-baaed level* (e.g., mine
 tmlinjjii one order of nuigTUiude above: health-
 ba»E*d lev el B in aoil)
 Complex mixture  of he!ten>fl,;erieouu  wube
 without discrete hot, npcitji (e.g., heterogeneous
 municipal landfill wante)
l.i] ng- te rm a 1 1 ect i v« neiui ,
Reduction ol'Uiuidity , mobility, or vol-
ume through
IteHcluclion of inability through treat-

Co irt
Short•• term «IIectiwnaui,
 Soilla contaminated with high concentrations     Long-term
 of VOCs                                         Short-term
 CoDtJBuniiutiBd pvnci ad «'iil,(!i-
                                                                                                                 .1 iff .El.E;.!«i:E; UY
                       whem highly UIKJC
nul im n principal threal at « «it«
Treatment  in  prreferred when  highly  mobile
        l in n principal thireiit at. a tit*
CoiaUinm*nl: mny dlbrdhL(jh level of long-term
offectivenoiiii; trentmeiit nuy be difficult to ir:i-
pleinient biENCiiiune of iiiiniflKient treatimerit en-
piicrit.y for 1 nrj[ to large noope
of nite

Tiientmenlt of h«terc^[eneoui wsuite often diffi-
cult or infeuibltt, re praiiurribe certain remedial
    loir oirtiiui iiitaiLtionuii.
           TN'B ipnKcMii WK mit in thin inemonindiunni ains imtendod iiciiiiy for tins «i»»faK» oCGcrriEirnnniint pcnionniell. Thny »™ nat. lintendMI, new cnn UhxEy be ra)i«d
      , l» cTHiiti! any ri|[hlliii irriloi'c.snljl.i by any party in lhi(i(jiition with the U'niled Stalkni. El1 A afficuli may 4iicinfa h> fcilllow U>« iujj.lnricjr prorridM in thin
 nniEfflnirundiuri. or to act alt runLiirtoe iriith Uhm prktuncE!, buns.! aa am iLttulyirin otfuyadtte niu ciiircniniitainicen. l\f-int>ty nelortian dksaiikmii uis nude and juntillicil an
 a <:iui«iHi|pin:iflc hiuni, The Aicnnr)' aba raixnrvai th« right to dutnn« tttii pudanoi! at any taiini! without publk: nation.
6 - OSWER Directive  9355.0-27FS