PB97-963139
                                 EPA/541/R-97/146
                                 January 1998
EPA   Superfund
       Explanation of Significant Difference
       for the Record of Decision:
       Libby Groundwater Contamination
       Libby, MT
       1/22/1997

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           UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                               REGION VIII, MONTANA OFFICE
                        FEDERAL BUILDING. 301 3. PARK. DRAWER 10096
SF File Number                                       	
  fel'-' /-•')	  EXPLANATION OF SIGNIFICANT DIFFERENCES

                          Libby Ground Water Superfund She
                               Lincoln County, Montana

                     United States Environmental Protection Agency
                                    January 1997
      L INTRODUCTION

      This  Explanation of Significant Differences (ESD) is being issued by the U.S.
      Environmental Protection Agency (EPA) to modify certain remediation criteria
      established hi the Record of Decision (ROD) issued by EPA on December 30,1988,
      for the Libby Ground Water Superfund She (hereby referred to as "Libby" or the
      "Site") and identifies the documents that serve as the basis for the determination.

      EPA,  hi consultation with the Montana Department  of Environmental Quality
      (MDEQ), and after consideration of documents prepared pursuant to the first five-
      Year Review of the Libby Ground Water She, has determined that modifications to
      the remediation levels established hi the  1988 ROD are required to incorporate
      criteria developed since the ROD was issued.  Modifications to the ground water
      remediation levels apply only to the Upper Aquifer.  Remediation levels for the
      Lower Aquifer were established hi an ESD issued hi 1993 (EPA 1993a).

      The modifications to the remedy described in this ESD do not alter the select. I
      remedy hi  any fundamental aspect regarding scope,  cost, or performance.  In
      accordance with Sections 117(c) and  121 of the Comprehensive Environmental
      Response, Compensation, and Liability Act of 1980 (Superfund), as amended, 42
      U.S.C. Section 9601, fit SSSL. ("CERCLA"), and the regulations at 40 C.F.R. Section
      300.435(c)(2)(i), the National Oil and Hazardous Substances Pollution Contingency
      Plan (NCP), this ESD has been prepared for the following reasons:

            •     to provide the public with an explanation of the nature of the changes
                 to the remedy;

            •     to summarize the circumstances that led to the changes to the remedy;
                 and

            •     to  affirm  that the revised remedy  complies  with  all  statutory
                 requirements.

     MDEQ concurred on the ROD issued on December 30, 1988, and has participated
     in the review of information leading to this ESD, including the five-Year Review
                                                                    Printed on Recycled Paper

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Report, the Supplemental Protectiveness Evaluation and the Five-Year Review Site
Visit. MDEQ concurs on this ESD.

This document presents a summary of the changes to the  selected remedy and a
synopsis of information on the Site. The Administrative Record, which contains this
ESD and the complete documentation, is available for public review at the locations
indicated at the end of this report.
EL  SITE HISTORY AND BACKGROUND

The Libby Groundwater Super-fund Site is located in the northwestern corner of
Montana adjacent to the City of Libby, Lincoln County (see Figure 1). The Site
currently consists of a lumber and plywood mill that was owned and operated by
Champion  International  Corporation (hereafter  Champion)  from  1985  until
November 1993 when Stimson Lumber Company purchased the mill. Champion has
retained the responsibility for operation of the remediation efforts pursuant to a
consent decree entered hi the United States District Court for Montana.

From 1946 to 1969, the Site was operated as a wood treatment facility.  Wood
treating fluids, such as creosote [composed almost entirely of polynuclear aromatic
hydrocarbons (PAHs)] and pentachlorophenol (PCP) were known to  have  been
disposed  and spilled at several different locations at the facility during this tune.
Groundwater contamination was first noticed within a domestic well (located within
city limits) in 1979.  EPA began site investigations in 1980, and eventually placed the
Site on the National Priorities List of Superfund Sites in 1983.

In 1985,  studies were conducted to determine public exposure to contaminated
groundwater in the City  of Libby.   As a result of these  investigations, EPA
recommended that an alternative water source be supplied to residents whose wells
were  contaminated  by  groundwater gmanating  from the  faculty.    This
recommendation was approved in a September 26,1986 ROD and was implemented
by Champion. Champion began additional remedial investigation studies in  1986
involving characterization of all  contaminated    media, including bench  and
pilot-scale testing of remedial technologies.  In 1988, EPA and MDEQ signed a ROD
that selected final cleanup methods for the affected media, including the sous/source
area and the Upper Aquifer and an  Interim remedy for the Lower Aquifer.  A
Consent Decree requiring Champion to perform these cleanup activities was entered
in the Federal District Court of Montana hi October 1989. A summary of the 1988
selected remedy is provided in Section HI below.

Remedial design activities began shortly after the Consent Decree was signed. These
design activities included the preparation of remedial design documents that outline
the strategy and  design components of the  remedy  selected  for  both  the
contaminated soils and the contaminated Upper Aquifer.  Following approval of
design documents,  remedial action  implementation began.  Operation  of the
components of the selected remedy has continued since 1990.

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As ESB documenting the remedy selection for the Lower Aquifer was prepared and
issued in 1993.  Also included in the 1993 ESD was a determination to eliminate
three chemical constituents from the list of soil parameters that the soil remedy must
address.

A Five-Year Review of the Remedial Action was performed hi January 1995 at the
Libby Ground Water Site. The objectives of the Five-Year Review are: (1) to verify
that the remedy is operating and functioning as designed and that institutional
controls are in place and are protective and, (2) to evaluate whether the response
action selected for the site remains protective of human health and the environment.
The Five-Year Review conducted for the Libby she was performed in accordance
with the Office  of Solid Waste and Emergency Response (OSWER) Directives
9355.7-02 entitled "Structure and Components of Five-Year Reviews",(EPA 1991a)
and 9355.7-02A, entitled "Supplemeutal Five-Year Review Guidance", (EPA 1994a).

The Five-Year Review for the Libby site was triggered  by the initiation of a portion
of the remedy by the responsible party (Champion International Corporation) in
1989. The Five-Year Review includes recommendations for the adoption of updated
remediation levels for the she (excluding the Lower Aquifer) to assure that the site
remedy is protective of human  health and the environment.
     SUMMARY OF THE 1988 RECORD OF DECISION

The objective of the remedy selected in the 1988 ROD is to reduce human exposure
to both the soil and groundwater contaminants of concern (see ROD, pages 51-55).
The major components of this remedy consist of excavation and biological treatment
of contaminated soils within an onsite LTU, and the in situ biological treatment of
contaminated groundwater within the Upper Aquifer (including a pump and treat
system for the heavily contaminated groundwater and oily product, with treatment
occurring within a bioreactor system).  An interim remedy was selected for  the
Lower Aquifer that 'consisted of feasibility  testing of biorestoration remedial
technologies, both alone and hi conjunction with oil recovery and oil dispersion
techniques (see ROD, page 55).

A complete list of the components of the current remedy selected for the Site can be
found on pages 2 through 5 of the ROD.  A brief summary of the existing remedy
includes the following excerpts:

•     Contaminated soils from the identified source areas will be excavated and
placed within a waste pit, that already contains contaminated soils and debris from
past disposal practices at the Site.  These contaminated soils will undergo a two-step
enhanced biodegradation process. The initial treatment phase will be conducted hi
the waste pit area, while the contaminants will be further degraded biologically after
transfer to the LTU.

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The LTU, which will be both lined and capped with low permeability materials, will
serve as a final disposition location.

•     The property owner shall be required to insert language within the current
registered deed identifying the locations of the hazardous substances disposal and
treatment areas, and  restrict the future land use of these areas.   This deed
restriction is considered part of the selected remedy for the soils/source area.

•     A combination of in situ bioremediation treatment processes will be utilized
to degrade organic contaminants in the saturated zone of the waste pit area.  A
closed loop, bacteria rich groundwater injection and extraction system  will be
employed in the waste pit area to remove and degrade contaminants adsorbed on soil
matrices.

•     The oil recovery wells will also  be used to collect  highly contaminated
groundwater, which will undergo treatment in a fixed film bioreactor prior to
reinjection through a rock percolation bed.

•     An in situ, enhanced biorestoration program will be initiated hi the Upper
Aquifer to reduce contaminant concentrations to required risk and ARAR-based
levels.  This innovative treatment technology  will address both the dissolved
constituents in  groundwater as well as  adsorbed contaminants on  the  aquifer
matrices concurrently.

•     An interim remedy was selected for the Lower Aquifer which required the
FRP to conduct a pilot test to determine if enhanced biorestoration of the aquifer,
both alone and in conjunction with oil recovery and oil dispersion techniques, is an
effective method of remediation.

•     The city ordinance prohibiting drilling new  water supply  wells within city
limits (both within the Upper and Lower Aquifers) will be continued.

•     Monitoring activities required to assess the performance of the components
of the remedy will be perforated throughout the life of the remedial activities at the
Site.  Long-term monitoring of the Lower and Upper Aquifer water quality is also
required to determine  further movement of the respective contaminant plumes,
ensure protection of public  health and assess potential degradation of Kootenai
River.

•     The Site conditions will be reviewed no less often than each five years after
initiation of remedial action to ensure that human health and the environment are
being protected by the remedy.

•     An ESD  selecting the final remedy for the Lower Aquifer was issued  in
September 1993.  The  final remedy for the Lower Aquifer consists of long term
ground  water monitoring and institutional controls limiting future water use.

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IV.  DESCRIPTION OF SIGNIFICANT DIFFERENCES TO THE REMEDY

The significant differences between the remedy described in the 1988 ROD and in
this  ESD are:

1.     The Maximum Contaminant Level (MCL) for Pentachlorophenol (PCP) in
ground water, adopted as a federal standard in 1992, will replace the current PCP
remediation level found in the ROD for the Upper Aquifer.  The MCL is  1.0
microgram per liter (ug/I).

2.     The MCL for Dioxin TCDD hi ground water, also adopted since the 1988
ROD was issued, calculated  using Toxicity Equivalence Factors (TEF), shall be
added to the remediation parameters in the RCD for the Upper Aquifer.  The MCL
for Dioxin TCDD is 3.0xlO'5ug/l.

3.     The MCL for each of the carcinogenic Polycyclic Aromatic Hydrocarbons
(PAHs) in ground water listed in Table 1.0 will replace the Total Carcinogenic PAH
remediation level found in the 1988 ROD for the Upper Aquifer.

4.     The soil remediation  level  for Total Carcinogenic PAHs is revised to 59
milligrams  per kilogram (mg/kg) calculated as Benzo-a-Pyrene (BaP) equivalents
using the EPA 1993 relative potency factors (RFPs).

5.    The  soil remediation levels  for Total Noncardnogenic PAHs, based on a
Hazard Index  Value of  1.0, listed  in  Table  1.0 will be added to  the  list  of
remediation parameters.

6.    The soil remediation levels for Dioxins/Furans will be revised as indicated in
Table 2.0 to reflect the  most recent  TEF methodologies for risk-bared    'tie
calculation.

Only those  changes described in paragraphs 1,  2, 3, 4, 5 and 6 above are being
made to the selected remedy described hi the 1988 ROD and 1993 ESD. All other
aspects of the selected remedy documented in the 1988 ROD and 1993 ESD remaiii
the same.  A more detailed description of the revised components to the remedy
follows.

Risk-Based Remedial Goals Review

Risk-based cleanup goals established in the ROD for both contaminated soils and
groundwater were reviewed to determine the impact of changes in the lexicological
assessment of PAHs and dioxins/furans using current EPA toxicological information
and updated relative potency factor (RPF) and Toxicity Equivalency Factor (TEF)
guidance (EPA 1989, EPA 1991b, EPA 1993c).   This review effort was performed
to assess the degree of protectiveness afforded by the current risk-based cleanup
goals documented in the ROD for Libby.

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The residential adult and construction worker exposure scenarios were used as the
basis  for 1988 cleanup levels presented in  the ROD for groundwater and soil,
respectively. The site-specific exposure parameters established in the human health
evaluation for these scenarios were used in the calculation of chemical concentrations
for specific target risk levels.  In the absence of site-specific information, standard
default exposure parameters were used in the calculations.  Risk-based cleanup goals
were also prepared for contaminants with MCLs for comparison purposes only.

A summary of the results of this risk-based cleanup goal review effort is presented
hi Table 1.0 and Table 2.0.  Details regarding the methods and input parameters
used to develop the  1994 risk-based cleanup goals presented in these tables are
provided in the Supplemental Remedy Protectiyeness Evaluation (Jacobs 1994b).

      Groundwater Cleanup Goals

The comparison of the 1988 risk-based cleanup goal for total noncarcinogenic PAHs
(0.4 /tg/L) established under the residential adult groundwater ingestion exposure
scenario differs substantially from the  1994 values calculated for the individual
noncarcinogenic PAHs, which ranged from 1,460 to 11,000 pg/L (Table 1).  This is
most  likely attributable to the  difference in  the toxicological  assessment  of
noncarcinogenic  PAHs in  1988  versus 1994.    Carcinogenic  promotion  (or
co-carcinogenicity) by the noncarcinogenic PAHs was assumed when the 1988 ROD
value was promulgated. Currently, carcinogenic potency values are used to evaluate
any carcinogenic  response  from PAHs.   The  1994 risk-based  values  for
noncarcinogenic PAHs provided in Table 1.0 address potential noncarcinogenic
effects only.   Carcinogenic  promotion by  noncarcinogenic PAHs is no longer
considered in estimating potential carcinogenic effects from  exposure to PAHs.

The range of the chemical-specific 1994 risk-based cleanup goals derived for
carcinogenic  PAHs is 0.1 to 0.0001 /ig/L.  The 1988 cleanup  goal for  total
carcinogenic PAHs is 0.04 pg/L.  The difference primarily is a result of the changes
to RTFs published by EPA for the carcinogenic PAHs (Jacobs 1994b). The more
recent RTFs  were applied to the risk-based quantification of cleanup goals for
carcinogenic PAHs ?n this review.  However, a majority of the carcinogenic PAHs
have  been  assigned an MCL since the tune the ROD was  signed.  Furthermore,
those PAHs listed hi Table 1.0 that do not have an MCL (fluoranthene and pyrene)
are no longer considered by EPA to be carcinogenic, as assumed at the time the 1988
risk-based  cleanup goals were developed for  the Libby site.

      Soil Cleanup Goals

The comparison of the 1988 and 1994 risk-based values for the soil contaminants
specific to  the Libby site is presented in Table 2.0. As described earlier, current
RPF  and  TEF  methodologies  were used  in developing  the  1994 values for
carcinogenic PAHs and dioxins/furans,  respectively (EPA 1993c). Using the 1994
methodology,  chemical-specific risk-based cleanup goals are presented for the
individual  contaminants of concern; cleanup goals under the 1988 approach were

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established for total carcinogenic PAHs and total dioxins/furans.

The 1994 risk-based cleanup goal calculated for FCP (36 rag/kg) closely matches the
1988 value of 37 mg/kg.
V.     SUMMARY  OF  STATE COMMENTS   AND  AVAILABILITY  OF
ADMINISTRATIVE RECORD

As stated above, MDEQ has reviewed the documents that serve as the basis for this
determination and has provided comments to EPA on the documents.  All of the
MDEQ comments were  incorporated  into the final reports.  MDEQ has been
provided with the opportunity to review and comment on this ESD.

Documents referenced within this ESD are part of the Administrative Record for the
Libby Site. The administrative record will also contain any written public comments
that may be received regarding this ESD. The complete administrative record for
the Site is available for public review at the following location:
U.S. EPA Montana Office
Federal Building, Room 192
301 South Park, Box 10096
Helena, Montana  59626-0096
(406) 441-1150
Mon-Fri, 8:00 a.m. to 5:00 p.m.
                                   Office of the County Sanitarian
                                   Lincoln County Annex
                                   418 Mineral Avenue
                                   Libby, Montana  59923
                                   (406) 293-7781
                                   Mon-Fri, 7:30 a.m. to 4:30 p.m.
VL AFFIRMATION OF STATUTORY REQUIREMENTS

Considering the new information that has been developed and the changes that have
been made to the selected remedy, EPA, in consultation with MDEQ, believes that
the remedy remains protective of human health and the environment, complies with
Federal and State requirements that are both applicable or relevant and appropriate
to this remedial action or involves appropriate waivers of these requirements, and
is cost-effective. In addition, the revised remedy utilizes permanent solutions and
alternative treatment technologies to the mavinnim extent practicable for the Site.
VIL APPROVAL
Max. H. Dodson, ARA
Office of Ecosystems Protection and Remediation
                                              Date

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Jacobs Engineering Group, Inc. 1994a.  Trip Report No. 25, July 11 and 12,1994.
Five- Year Review Site Visit. Libby Groundwater Superfund Site. Libby, Montana.
Prepared for the U.S. Environmental Protection Agency, Region VHI, Montana
Operations.

Jacobs Engineering Group, Inc. 1994b. Five-Year Review, Supplemental Remedy
Protectiveness Evaluation. Libby Groundwater Superfund Site. Libby, Montana.
Prepared for the U.S. Environmental Protection Agency, Region Vm, Montana
Operations.

U.S. Environmental Protection Agency. 1994a. Supplemental Five-Year Review
Guidance, Office of Solid Waste and Emergency Response, OSWER Directive No.
9355.7-02A.

U.S. Environmental  Protection  Agency.  1993a.   Explanation  of Significant
Differences, Libby Ground Water Superfund Site.

U.S. Environmental Protection Agency.  1993b. Region VHI Montana Operations
Office, Superfund Preliminary Site Close Out Report (Long Term Remedial Action).
Libby Groundwater Superfund Site. Libby, Montana.

U.S. Environmental  Protection  Agency.    1993c.  Provisional  Guidance  for
Quantitative Risk Assessment  of Polycyclic Aromatic Hydrocarbons.  Office of
Research and Development, Washington, DC.

U.S. Environmental Protection Agency. 1991a.  Structure and Components of
Five-Year  Reviews, Office of Solid Waste and Emergency Response, OSWER
Directive No. 9355.7-01, Washington, DC.

U.S. Environmental Protection Agency. 1991b. Human Health Evaluation Manual,
Part B: "Development of Risk-Based Preliminary Remediation Goals." Office, of
Solid  Wastu  and Emergency Response,  OSWER  Directive  No.  9285.7-01B,
Washington, DC.

U.S. Environmental Protection Agency.  1989 (March). Interim Procedures  for
Estimating Risks  Associated with  Exposures  to  Mixtures  of  Chlorinated
Dibenzo-p-Dioxins and —Dibenzofurans, EPA No. 625/3-89/016.

U.S. Environmental Protection Agency.  1988. Region Vm Montana Operations
Office, Record of Decision, Libby Groundwater Superfund Site, Libby, Montana.

Woodward Clyde Consultants.  1994a. Lower Aquifer Monitoring Program for the
Libby Site. Libby Groundwater Superfund Site. Libby, Montana.  Prepared for
Champion International Corporation.

                                    8

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Woodward Clyde Consultants.  1994b.  LTU 1993 Annual Operational Report,
Libby Groundwater Super-fund Site.  Libby, Montana.  Prepared for Champion
International Corporation.

Woodward Clyde Consultants.  1994c.  1993 Annual Operational Report for the
Upper .Aquifer, Libby Groundwater Superfund Site.  Libby, Montana.  Prepared
for Champion International Corporation.

Woodward Clyde Consultants.  1993a.  Lower Aquifer Characterization Report.
Libby Groundwater Superfund Site.  Libby, Montana.  Prepared for Champion
International Corporation.

Woodward Clyde Consultants.  1993b. Technical Evaluation Report for the Lower
Aquifer, Final.  Libby Groundwater Superfund Site.  Libby, Montana.  Prepared
for Champion International Corporation.

Woodward Clyde Consultants.  1993c,  Focused Risk Assessment Report for the
Lower Aquifer, Final.  Libby Groundwater Superfund Site.  Libby, Montana.
Prepared for Champion International Corporation.

Woodward Clyde Consultants.  1993d.  LTU 1992 Annual Operational Report,
Libby Groundwater Superfund Site.  Libby, Montana.  Prepared for Champion
International Corporation.

Woodward Clyde Consultants. 1992. LTU 1991 Annual Operational Report, Libby
Groundwater Superfund Site.   Libby, Montana.   Prepared  for Champion
International Corporation.

Woodward Clyde Consultants.  1990.  No Migration Petition, Land Treatment
Units, Final. Libby Groundwater Superfund She.  Libby, Montana. Prepared for
Champion Intr'•national Corporation.

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                                                1
Lincoln Coonty
    Montana
SCALE 1:2400*
                                       Plywood
                                        and
                                      Mill Facilities
                   Figure!
        LIBBY GROUND WATER SITE
             LIBBY, MONTANA

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                                      TABLE 1.0
                        COMPARISON OF 1988 CLEAN-UP GOALS,
                     MAXIMUM CONTAMINANT LEVELS (MCLs), and
                     1994 RISK-BASED CLEAN-UP CONCENTRATIONS
                                   (GROUNDWATER)
'
CONTAMINANTS
OF CONCERN
1988 VALUES
CLEAN-UP GOAL
(tt/L)
BASIS***
1994 VALUES
CLEAN-UP
CONCENTRATION
(ft/L)
BASIS
Noncardnofcnk PAH Coopoundi
Naphthalene
Aceaapthylene
AcefuathenA
Fluorene
Anthracene
Flaoxaatfaenet6)
Py»ne
Bouo (g,lu) pnylene
(•)
f*iiif tiMMMiltf PAfT OnmiMM •••*!•

A— «*(a)
pynaaW
Quyaeno
••""" \*/ • •••••»«•»
Benzo (b) floomAMw
Ben2o(k) flnoiintfacia*
Benzo (•) pjrraoe
Indeao (l,2^-e,d) pjmaa
Dibouo (ft>h) •atfancm*
PtTrtnfhfir-phrnol

Bonn.
Anenk

(4)
1050
5.00
50.00
Evidence of
promoting
cuonofenic tcovitf

Ruk-Bmd
VibM
10*
and
AddmaU*
^j^DuK
LaVtCtUaW
Heaidi
AdrUoty
MCL
MCL
1460
N/A
2190
1460
N/A
11000
1460
1100
NA

N/A
N/A
0.2
0.1
0.2
0.2
0.2
0.4
0.3
1.0
5.00
50.00
Rlak-Rised
Value
m-i.o

N/A
N/A
MCL
MCL
MCL
. MCL
MCL
MCL
MCL
MCL
MCL
MCL
(.)-
  .    QnatUihr* i
ifcr d iwiriniliiuiiiiiuPAiU riMl
KCaSSca IB I98& not **>••"•!•>>*
i fc» «B cuciaotwie PAH* rfuO
                                                                             ta 1994.
HI -
MCL - MuJwrnCeat
NA -  aoctpp&abte
PAH - poJycjreBe
fig/1. - mietofmni p«r Gttr

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                                           TABLE 2.0
                           COMPARISON OF 1988 CLEAN-UP GOALS AND
                           1994 RISK-BASED CONCENTRATIONS (SOILS)

. CONTAMINANTS
OF CONCERN
Furaai:
ten (24.7,8)
ten (non-24,7,8)'
peata (1.24,7,8)
peata (24,4,7,8)
peata (other)
hexa (24,7,8)
hexa(aon-24.7.8)
hepta (24.7,8)
heptt (ooa-24.7.8)
octa
Dioxiatt
ten (24,7.8)
ten (000-24,7,8)
peata (24.7,8) •
peata (noo-24,7,8)
hexa (24.7.8)
hexa (aoa-24,7,8)
hepta (24,7.8)
hepta (aoa-24,7,8)
•*--*- -JilnaMiailiaMnl
intaiaCBiiinipiiciiui
4
CudMfcak PAHss




ChiyMat
Iadeao(144-ed)p]rraw
Noaeardaoteak PAH*
Acensphthea*
Aceaaphthyteao
Aofanceae
Fhionaiheae
Fluoreae
1988 VALUES
CUAN4JPGOAL
fet/1,0










W



£37




M




NA
NA
NA
NA
NA

BASS"





Risk-Baaed

Value*'
Iff*




Risk-Band.
VaW»
Iff*


BOAT



Risk-Based
Value
Iff*




(«0

1994 VALUES
CLCAN-OT
CONCENTJUTION
(aaykfj

0.0289
NA
0.0578
0.00578
NA
0.0289
NA
0.289
^A
2^9
0:00289
NA
0.00571
NA
0.0289
NA
OJ89
NA
2^9
.36


59
594
594
5^40
59.400
59
594

166
. NA
33
250
250
ilncliMUd iliti«nn f iliuiiimml ilitiaimfliiini rnntilmd S 0.00
BASIS


Risk-Based
Value
Iff1





'
Risk-Based
Value
Iff'



Risk-Based
Valiw
Iff*

Risk-Baaed
Value
Iff'





Risk-Based
Value
HI-1.0

Inj/kf.
(b)-
(e) •   Tool cuciaofMia PAH
s U oat/kf.

BOAT -  BM DMmMBcttd Available Technology
m -    NaeeareiaotwioKaant fades
NA -   ootipelieable
PAH •   polyeyelie (cooulic bydfoeaiboa
     •  aillignms per kUognm

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       UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

                        REGION VIII. MONTANA OFFICE
                  FEDERAL BUILDING. 301 S. PARK. DRAWER 10038
               "        HELENA. MONTANA 69626-0096
Ref:  8MO

March 21,  1997

Ralph Heinert
Manager Environmental  Projects
Champion International Corporation
P.O. Box 1590
Libby, MT

Dear Mr.

     Attached is a  copy of the  final  Explanation of Significant
Differences, January 1997 (BSD)  for the Libby Ground Water Site.
The final  BSD was signed  on January 21,  1997.

     EPA is currently  preparing an announcement of the issuance
of the 1997 BSD that will be sent  to  the Libby Site mailing list
this month.  A draft of the fact sheet  will be sent to you next
week.

     Would you please  provide a copy  of the final BSD and
supporting documents to the County Sanitarian's Office as soon as
is convenient?  The fact  sheet  and a  public announcement to be
published  in the Western  News will indicate that the BSD and
supporting documents will be available  for review both at the EPA
office in  Helena and at the sanitarian's office in Libby.

     Thank you for  your assistance.   Please let me know if you
have any questions  concerning this request.


                                 Sincerely,
                                    !3 C.  Harris,  P.E.
                                 Remedial  Project  Manager
Attachment:
cc:  J. Carraway, Champion, Stamford
     N. Marsh, MDEQ
                                                        Printed on Recycled Paper

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                                                  CONCURRENCE COPY
Ref:  6MO

March 21, 1997

Ralph Heinert
Manager Environmental Projects
Champion International Corporation
P.O. Box 1590
Libby, MT 59923

Dear Mr. Heinert:

     Attached is a copy of the final Explanation of Significant
Differences, January 1997 (BSD) for the Libby Ground Water Site.
The final BSD was signed on January 21, 1997.

     EPA is currently preparing an announcement of the issuance
of the 1997 ESD that will be sent to the Libby Site mailing list
this month.  A draft of the fact sheet will be sent to you next
week.

     Would you please provide a copy of the final ESD and
supporting documents to the County Sanitarian's Office as soon as
is convenient?  The fact sheet and a public announcement to be
published in the Western News will indicate that the ESD and
supporting documents will be available for review both at the EPA
office in Helena and at the sanitarian's office in Libby.

     Thank you for your assistance.  Please let me know if you
have any question : concerning this request.


                                Sincerely,
                                James C. Harris, P.E.
                                Remedial Project Manager
Attachment:
cc:  J. Carraway, Champion,  Stamford
     N. Marsh, MDEQ
FCD:  March 21, 1997:jimh:esdralph

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