PB95-964033
                                 EPA/ROD/R04-95/249
                                 February 1996
EPA  Superfund
       Record of Decision:
       USDOE Oak Ridge Reservation,
       Lower Watts Bar Reservoir
       Operable Unit, Oak Ridge, TN
       9/29/1995

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                          DOE/OR/02-1373&D3
 Record of Decision for the
Lower Watts Bar Reservoir



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                          PREFACE
This  Record  of Decision for  the  Lower  Watts  Bar  Reservoir
(DOE/OR/02-1373&D3) was prepared in accordance with requirements
under the Comprehensive Environmental Response, Compensation, and
Liability Act to present the selected remedy to the public.  This work
was performed under Work Breakdown Structure 1.4.12.3.1.02 (Activity
Data Sheet 9302, "Lower Watts  Bar Reservoir").   This document
provides the Environmental Restoration Program with information about
the selected remedy  for Lower Watts Bar Reservoir, which involves
continuance of existing institutional controls and long-term monitoring
of water, sediment, and fish. Information in this document summarizes
information   from   the   remedial   investigation/feasibility   study
(DOE/OR/01-1282&D4)andtheproposedplan(DOE/OR/02-1294&D5).

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                  ACRONYMS AND ABBREVIATIONS
Ag          silver
ARAR       applicable or relevant and appropriate requirement
As          arsenic
Ba          barium
Be          beryllium
Cd          cadmium
CERCLA     Comprehensive Environmental Response, Compensation, and Liability Act
CFR         Code of Federal Regulations
cm          centimeter
Co          cobalt
COE         U.S. Army Corps of Engineers
Cr          chromium
Cs          cesium
Cu          copper
DOE         U.S. Department of Energy
EPA         U.S. Environmental Protection Agency
FFA         Federal Facility Agreement
Fe          iron
FS          feasibility study
g            gram
Hg          mercury
HQ          hazard quotient
LAG         interagency agreement
in.          inch
Ib           pound
LWBR       Lower Watts Bar Reservoir
Mn          manganese
NCP         National Oil and Hazardous Substances Pollution Contingency Plan
Ni          nickel
ORR         Oak Ridge Reservation
OU          operable unit
oz           ounce
Pb          lead
PCB         polychlorinated biphenyl
Ra          radium
RI           remedial investigation
ROD         record of decision
SARA        Superfund Amendments and Reauthorization Act
Se           selenium
Sr           strontium
TBC         to be considered
TDEC        Tennessee Department of Environment and Conservation
TRM         Tennessee River mile
TVA         Tennessee Valley Authority
Zn          zinc
JT9SQ327.2DH/C1E
                                       111
                                                                           IB* 1995

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                  PARTI. DECLARATION
JT9S03Z7.2DH/OE        .                                      s^,nt-. 18, 1993

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                      SITE NAME AND LOCATION

      Lower Watts Bar Reservoir Operable Unit
      Oak Ridge Reservation
      Oak Ridge, Tennessee


               STATEMENT OF BASIS AND PURPOSE

      This decision document presents the selected remedial action for the Lower Watts Bar
Reservoir (LWBR)  Operable Unit (OU).  This remedial action was selected in accordance with
the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as
amended by the Superfund Amendments and Reauthorization Act (SARA) (42 United States Code
9601 et seq.), and to the extent practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP), 40 Code of Federal Regulations (CFR) 300. This decision is based on
the administrative record for this site.

      The U.S.  Department of Energy (DOE) issues this document as the lead agency.  The
U.S. Environmental Protection Agency (EPA) and Tennessee Department of Environment and
Conservation (TDEC) are supportive agencies as parties to the Federal Facility Agreement (FFA)
for this response  action, and they concur with the selected remedy.


                        ASSESSMENT OF THE OU

      If actual or threatened releases of hazardous substances from this OU are not addressed
by implementing the response action selected hi this record of decision (ROD), they could present
substantial endangerment to public health, welfare, and/or the environment.


               DESCRIPTION OF SELECTED REMEDY


      •  The selected remedy for the LWBR OU addresses the contamination of the Watts Bar
         Reservoir area from Tennessee River mile (TRM) 529.9 at Watts Bar Dam upstream
         to TRM 567.5 at the confluence of the Clinch and Tennessee Rivers.
JT950327.2DH/CJE                            1-2                            Sqttnte 18, 1995

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       •  The response action was chosen from a full range of actions that could possibly
          address the two primary risks identified in the remedial investigation (RI).  Risks to
          human health posed by LWBR include exposure to metals in deep sediment of the
          main  river channel and  to  polychlorinated biphenyls (PCBs), chlordane, aldrin,
          arsenic,  and mercury in fish tissue.  The same response actions are applicable to
          reducing ecological risk in LWBR.

       •  The selected  remedy uses  existing institutional controls to reduce exposure to
          contaminated  sediment;  fish consumption  advisories  to  reduce  exposure to
          contaminants  in fish  tissue;  and annual monitoring to detect changes in LWBR
          contaminant  levels or mobility.   DOE will be responsible for undertaking any
          appropriate CERCLA response actions.

       •  An  interagency agreement  (LAG) among DOE,  TDEC, EPA, Tennessee Valley
          Authority (TVA), and the U.S. Army Corps of Engineers (COE) became effective in
          February 1991.  The LAG is  used to coordinate and review permitting and other use
          activities  resulting from DOE operations that could result  in the disturbance,
          resuspension,  removal, and/or disposal of contaminated sediments or  potentially
          contaminated sediments in Watts Bar Reservoir.


                     STATUTORY DETERMINATIONS


       The selected remedy protects human health and the environment, complies with federal
and state  requirements that  are legally applicable or relevant and appropriate  requirements
(ARARs), and is  cost-effective. Hazardous substances above health-based levels will remain on
site if this  remedy  is  implemented.   A review  will be conducted  within  5 years  after
commencement of remedial action, according to CERCLA Section 121, to ensure that the controls
and advisories for LWBR continue to  adequately protect human health and the environment.
Also,  DOE  has  agreed to provide status reports to TDEC and  EPA on the monitoring and
assessment program for LWBR.
mS03Z7.2DH/CJE                               1-3                             Sqxemfccr 18, 1995

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APPROVALS
          l, Manager
  v.S. Department of Energy
  Oak Ridge  Field Office
                                     Date
                          r, DOT-Oversij
  Earl C. Leming, Director, DOT"Oversight Division
  State of Tennessee
  Tennessee Department of Environment and Conservation
                                     Date
M,
 John Hankinson, Regional Administrator
 U.S. Environmental Protection Agency
 Region IV
                                     Date
nVSQ327.2DH/CJE
       1-4
                                             |g, 1995

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                PART 2.  DECISION SUMMARY
JTO03Z7.2DH/CIE                                                 September 18, 1995

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             OU NAME, LOCATION, AND DESCRIPTION

      The LWBR OU consists of the Watts Bar Reservoir, which is impounded by the Watts
Bar Dam in East Tennessee, almost equidistant (about 62 miles) from the cities of Knoxville and
Chattanooga.  Watts Bar Reservoir flows through portions of four counties in East Tennessee
(Loudon, Roane, Rhea,  and Meigs).  The reservoir  extends from the  dam at TRM 529.9
upstream on the Tennessee River 72 miles to Fort Loudon Dam (TRM 602.3) near Lenoir City,
and an additional 24 miles up the Clinch River to Melton Hill Dam (Clinch River mile 23.1) near
Oak Ridge.

      The LWBR study area extends from TRM 567.5 at the mouth of the Clinch River to TRM
529.9 at Watts Bar Dam (Fig. 2.1).  Under CERCLA, the downstream boundary of the Oak
Ridge Reservation (ORR) is Watts Bar Dam. Watts Bar Reservoir is one of nine mainstream
impoundments on the Tennessee River between Paducah, Kentucky, and Knoxville, Tennessee.
This reservoir provides  flood control,  hydropower generation,  navigation,  municipal  and
industrial water supply, wildlife habitat, and recreation.

      The downstream boundary of the ORR was  placed at Watts Bar  Dam because earlier
studies had shown that the vast majority of sediment-associated contaminants released from ORR
had collected in lower Watts Bar Reservoir. Consequently, concentrations of sediment-associated
contaminants released from ORR are much lower in  reservoirs downstream of Watts Bar Dam.
The level of Oak Ridge-derived contaminants detected in past studies in  the Tennessee River
system below the Watts Bar Dam were well below the concentrations determined to be of human
health concerns by the baseline risk assessment within the Watts Bar Reservoir.


                                 OU HISTORY

      LWBR is contaminated because of past  activities at DOE's ORR and other non-DOE
sources. ORR is comprised of three major installations—the Oak Ridge National Laboratory, the
Oak Ridge Y-12 Plant, and the Oak Ridge K-25 Site (formerly the Oak Ridge Gaseous Diffusion
Plant). These facilities were built in the 1940s as research, development,  and process facilities
in support of the Manhattan Project.  Activities at these facilities have resulted in the release of
hazardous  substances and radioactive contamination to the on-site and off-site environment.  In
March 1995, DOE presented the public with the proposed plan for LWBR and solicited public
comments.  The proposed plan presented monitoring and institutional controls as the preferred
remedial action.


JT9S03Z7.2DH/OE                               2-2                              September 18, 1995

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      The current or threatened release of hazardous substances from CERCLA-specific sites
on ORR is the focus of current source control actions. These releases are being quantified at the
source; similarly, remedies will be effected at the source. The LWBR RI determined contaminant
concentrations in LWBR fish, water, and sediment and the threat those contaminants might pose
to human health and the environment.  The measurement of ambient concentrations in these
media inevitably integrates all of the contaminant sources mentioned above for ORR, as well as
any non-ORR sources that contribute to LWBR.


         HIGHLIGHTS OF  COMMUNITY PARTICIPATION

      An Rl/feasibility study  (FS) was conducted in accordance with CERCLA requirements,
including the public participation requirements of CERCLA Sections 113(K)(2)(B)(i-v) and 117.
Newspaper notices indicated the availability of documents at the Information Resource Center in
Oak Ridge, Tennessee, and announced public meetings.  The RI/FS and proposed plan were
released to the public in March 1995. DOE encourages public participation in commenting on
the preferred alternative for LWBR and set a comment period of March 24 to April 28, 1995.
An information  bulletin was also prepared to summarize this proposed action and facilitate
community participation.

      Public meetings were held April 4, 1995, in Kingston, Tennessee, and April  11, 1995,
in Spring City, Tennessee. The Responsiveness Summary of this ROD provides a summary of
the major issues  raised during the public comment period. This decision document presents the
selected remedial action for management of LWBR in accordance with CERCLA, as  amended,
and NCP to the maximum extent practicable.   The  decision for this site  is based on the
Administrative Record.


                     SCOPE AND ROLE OF THE OU

      LWBR is the first impoundment downstream of ORR. Contaminants from ORR are
primarily transported to LWBR by the Clinch River.  Any surface waters originating on or
passing through  ORR flow into the LWBR OU.  Because the reservoir is an efficient sediment
trap, LWBR OU sediments contain contaminants released from ORR and have the potential of
receiving current or future contaminant releases.   The selected  remedy for the LWBR OU
addresses potential risks caused by ingestion of vegetables grown in contaminated sediments and
contaminated fish, milk, and meat.

JT9S0327.2DH/CIE                              2-4                              September 18. 1995

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                           OU CHARACTERISTICS

      Construction of Watts Bar Reservoir began in 1939 to provide navigation, flood control,
and hydrogeneration  of electricity.   Land  surrounding  the reservoir  is currently  used for
residential, agricultural, industrial, resort, and recreational purposes. Waters of the reservoir are
used for domestic water supply,  industrial water supply, fish and  aquatic life,  recreation,
irrigation, livestock watering, wildlife, and navigation.  LWBR is not a direct source of drinking
water for municipalities; however, Rockwood and Spring City drinking water intakes could be
impacted during high water conditions by reverse flow.  Kingston drinking water intake in the
Tennessee River above LWBR is also impacted by reverse flow.

      The LWBR OU is an integrator of waterborne substances in the Clinch and Tennessee
Rivers.  Once these substances enter the LWBR OU, they may be found in the water, sediment,
or biota. The fate of a substance depends on the flow rate of the reservoir's surface water and
the physical and chemical properties of the substance.  Dissolved substances are usually flushed
through the reservoir  in  a matter  of weeks,  whereas  particle-associated substances  may
accumulate in the  sediments and remain indefinitely.

      Peak concentrations of 137Cs and Hg are found  in deep-water sediments in the old river
channel.  The highest concentrations of each are generally buried  20-80 cm (8-32 in.) in the
sediments of the old river channel. Near-shore sediments contain >37Cs near background levels.

      Panicle-associated  and  dissolved contaminants  accumulate  in  LWBR  OU  biota.
Contamination of LWBR OU fish with PCBs and pesticides is documented.  Sampling data
indicate that sediment and surface water contamination  by  organic  compounds is  minimal.
Inorganic contaminants in LWBR OU  sediments are similar  to those found in  other  TV A
reservoirs.  They include  As, Ba, Be, Cd,  Cr,  Cu, Fe, Pb, Mn, Hg, Ni,  Se,  Ag, and Zn.
Radionuclides detected in sediment, fish,  or surface waters include  I37Cs, wCo, ""Sr, and ^Ra.


                          SUMMARY OF OU RISKS

      A baseline risk assessment evaluated potential current and future risk to human health and
the environment posed by radioactive and chemical contaminants at LWBR if remedial action was
not taken. Results from this assessment were used to determine a need for action at the site.
JT950327.2DH/OE                               2-5                               September 18. 1995

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       The greatest risk to human health from contaminants  in LWBR is associated with the
consumption of certain PCB-contaminated fish species. Mercury, chlordane, aldrin, and arsenic
in fish also pose potential risks. Because of their low body weight, children are potentially at
greater risk than adults; most contaminants pose a potential threat only to children.  If deep-water
sediments were dredged and used for farming, several contaminants could pose a risk to human
health through consumption of the resulting agricultural products (i.e., vegetables, milk, and
meat).  In place,  these sediments do not pose  a risk to human  health because no exposure
pathway exists.  Levels of ORR contaminants in near-shore sediments are low.  No unacceptable
risk to human health from LWBR surface water was identified for any exposure pathway.

       The screening level ecological risk assessment indicated that LWBR sediment is potentially
toxic to benthic organisms, although conclusive evidence is lacking and the cause of any toxicity
has  not been established.  Additional data will  be collected  through a long-term monitoring
program as a component of the 5-year CERCLA review of the ROD.

       Risk assessment provides the basis for actions and indicates the exposure pathways that
need to be addressed by the remedial actions.  It serves as the baseline, indicating what risks exist
if no action is taken. Table 2.1 lists the exposure pathways and the contaminants that have cancer
risks of > 10~4 or hazard quotients (HQs) >  1.

       Risk presented by remaining contaminants steadily diminishes through continued decay
of radioactive  materials,  environmental degradation, and  the deposition of additional  river
sediment over existing contaminated  areas.  Some of the potential problems, particularly with
l37Cs, will greatly diminish over time without further action.  Monitoring of water, sediment, and
fish  will continue to detect any change in risk to human health and/or the environment.

HUMAN HEALTH RISKS

       The human health risk assessment in the LWBR OU Risk Assessment Report assessed risk
to the public based on five scenarios: (1) a fisherman whose family eats his catch most days,
(2) a person living near the shore who spends much of each year in contact with (and sometimes
ingesting) near-shore sediments and the surface water, (3) a family that uses dredged sediments
as topsoil and subsists mostly on livestock and  vegetables  from their farm, (4) a family that
irrigates their farm with surface waters and subsists mostly on livestock and vegetables, and (5) a
family that uses raw, untreated surface water as a drinking water source.

       For the LWBR OU, the fish ingestion pathway is the most significant exposure pathway
for human health risk, even though only PCBs pose a cancer risk greater than 1 x 10~4. Mercury

JT950327.2DH/CJE                                2-6                              September 18, 19*5

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concentrations in fish produced an HQ of 1.5 for a child 3-6 years of age. Chlordane and aldrin
concentrations in fish produced HQs of 5.4 and 1.0, respectively, for children. Catfish, striped
bass, hybrid striped bass-white bass,  white bass,  sauger,  carp,  small mouth  buffalo, and
largemouth bass are the most contaminated fish species.

       Human health risk assessment results are interpreted as follows:

       •  Ingestion of certain fish species from the LWBR OU at an average rate near 54 g
          (1.9 oz)/day for 30 years can result in carcinogenic and noncarcinogenic health effects.

       •  Surface waters of the LWBR OU do not present an unacceptable risk from chemical
          or radionuclide contamination,  even in extremely conservative conditions.

       •  Shallow, near-shore sediments of the LWBR OU do not present an unacceptable risk
          to the public.

       •  Sediments in the main channel  of the LWBR OU do not present  a risk  to the public
          if left undisturbed, but can  present a noncarcinogenic hazard to human health if
          dredged and used as topsoil for agriculture.

       Actual or threatened releases  of hazardous substances from this OU,  if not  addressed by
implementing the response  action selected in this ROD, may present substantial endangerment
to public health, welfare, and/or the environment.

ENVIRONMENTAL RISKS

       An ecological  risk  assessment  summarized  existing information.    More conclusive
ecological risk assessments  will  likely be performed using data collected in the Clinch River RI
and some LWBR monitoring data. Current data suggest that benthic organisms and piscivorous
wildlife might be at risk, but a specific cause is unknown and feasible remedies do  not currently
exist. After careful review  of ecological risk data, DOE has determined that no remedial  action
to reduce ecological risk is required for the LWBR environment.   Data  from the Clinch
River/Poplar Creek RI and the post-ROD monitoring on LWBR will be used to confirm that this
decision remains acceptable.
TT950327.2DH/OE                               2-8                               Scpttrober 18. 1995

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                   DESCRIPTION OF ALTERNATIVES
SHORT-TERM EFFECTIVENESS

      Regulatory procedures on sediment-disturbing activities and fish consumption advisories
are effective in the short term.
LONG-TERM EFFECTIVENESS

      The preferred alternative has the best long-term effectiveness. Health risks under this
alternative would not exceed current levels and future risks would diminish as natural processes
continue  (radioactive decay  for  contaminants in  sediment  and decrease  of contaminant
concentrations in fish as source areas on land are removed).  Institutional controls on sediment
disturbance  and fish consumption would remain  in place.  Additional controls could be
implemented if human or ecological exposure to contaminants change.

REDUCTION OF TOXICITY, MOBILITY,  AND VOLUME THROUGH TREATMENT

      Although natural processes would reduce contaminant toxicity, mobility, and quantity
under this alternative, active treatment would not take place.  The monitoring plan included in
this alternative will allow DOE, in cooperation with the state of Tennessee and EPA, to determine
any changes in toxicity, mobility, or quantity of contaminants.

IMPLEMENT ABILITY

      The state of Tennessee and other federal agencies are already implementing the main
components of the preferred alternative.  The LAG for Watts Bar Reservoir Permit Coordination
defines DOE's responsibility to support activities that are above and beyond normal permitting
requirements as related to sediments contaminated by DOE activities. The monitoring plan could
be easily  implemented because similar activities have been in progress for many years at ORR.

COST

      The cost of the preferred alternative is much lower and a more effective use of funds when
compared to active remediation of sediments.
JT950327.2DH/CIE                              2-9                             September 18, 1995

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                         THE SELECTED REMEDY

       DOE, EPA,  and the state have determined that controls and advisories are the most
appropriate remedy for the LWBR OU, based on a review of CERCLA requirements, detailed
analysis of the alternative, and public comments.  This alternative represents the best balance
among the evaluation criteria for remedial actions when considered in the context of public
comments received.

CONTINUANCE OF EXISTING CONTROLS, AND ADVISORIES REGARDING LWBR
ACTIVITIES

       One threat to human health posed by the LWBR OU is consumption of certain species of
fish. Under the Tennessee Water Quality Control Act, TDEC 1200-4-3, TDEC is authorized to
issue fish consumption advisories to protect the public.  The Division of Water Pollution Control
in TDEC currently posts two types offish consumption  advisories at approximately 50 public and
private access points surrounding the LWBR OU.  A precautionary  advisory, the mildest form
of advisory, warns children, pregnant women, and nursing mothers  to avoid eating white bass,
sauger,  carp, smallmouth buffalo, and largemouth  bass.   All others  are warned to limit
consumption of those fish to 1.2 Ib/month.  A no consumption advisory warns the public to avoid
eating catfish, striped bass, and hybrid striped  bass-white  bass in  any amount.  LWBR OU
advisories are issued because of PCS content in fish tissues.  The recent revisions (July 30,1995)
to fish advisory procedures changed the standards so  that the no consumption advisory is  for
typical consumers and protects to a level of 10~4, while the precautionary advisory is for sensitive
consumers such as pregnant women and children and protects to a level of 10~5.   When an
advisory is issued or changed, a press release is issued and signs are placed at highly used access
pomts.  A list of advisories is printed in the Tennessee Fishing Regulations published  by  the
Tennessee Wildlife Resources Agency. Telephone numbers are provided if the public desires
further information regarding an advisory.  TDEC provides standards  for domestic water supplies
and water quality criteria for recreational waters  (TCA 69-3-101, et  seq. and TDEC 1200-4-3).
These standards protect the public by ensuring that drinking  water taken from the LWBR OU is
treated to a  safe level for public consumption and by ensuring that contaminant levels in  the
reservoir are low enough for safe recreational use.

       As lead agency, DOE will continue working with appropriate statutory authorities through
the  LAG to  coordinate and support the implementation of existing institutional controls and
advisories.  DOE must consider, propose, and  implement  appropriate response actions if an
ms0327.2DH/CJE                              2-10                             September 18. 1995

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existing control or advisory becomes ineffective for any reason or if a sediment-disturbing activity
would, because of sediments contaminated by DOE activities, be potentially harmful to human
health and/or the environment.

MONITORING PLAN

      Monitoring of water, sediment, and biota will be continued to determine if there is a
change in the currently calculated risk that would pose a threat to human health and/or the
environment. Monitoring will be coordinated with TVA, TDEC, and other federal, state, and
local agencies.  Monitoring will begin in Fiscal Year 1996 and will continue for as long as
necessary. Data summary reports will be produced and made available to the public.  Collected
data will be  used in the CERCLA-required review of the remedial action.  If data warrant, a
review will be conducted earlier.


                  THE STATUTORY DETERMINATION

      As lead agency, DOE's primary responsibility is to undertake remedial actions that achieve
adequate protection of human health and the environment. In addition, Section 121 of CERCLA
establishes several other  statutory requirements  and  preferences.   This remedial action is
protective of human  health and the  environment; complies with CERCLA (as amended by
SARA), federal, and state requirements directly associated with  this action; and is cost-effective.

PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

      Analysis of existing data reveals no unacceptable risk to human health or the environment
from sediments, fish consumption, or surface water in LWBR OU under the conditions that this
alternative will maintain.   This alternative  is protective in that DOE will  ensure that future
activities which disturb sediments within LWBR will be done in a manner that is protective of
human health and the environment.   Natural sedimentation will  continue to cover existing
contamination and reduce its availability to the environment.  Also, radioactive decay of 137Cs will
lessen its contribution to risk over time.  This alternative will allow DOE to monitor for any
increase in contaminant levels and is  protective  in that DOE could respond to any  increases in
the overall system or to areas of higher concentrations should such areas be found.  There will
be no unacceptable short-term risks or cross-media impacts as a result  of implementation this
remedy.
JT950327.2DH/CJE                              2-11                              September 18. 1995

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COMPLIANCE WITH ARARs

       There are no chemical-, location-, or action-specific ARARs for the selected remedy;
however, there is to-be-considered (TBC) guidance for institutional controls when  residual
radioactivity is left in place.

INSTITUTIONAL CONTROLS

       Institutional controls will continue to limit access and exposure. There are no regulatory
requirements specifying institutional controls for CERCLA units. However, DOE Order 5400.5,
Chapter IV, requires administrative (institutional) controls  for long-term management  in areas
containing residual radioactivity.  Active controls specified in the DOE Order and TBC guidance
include restrictions, fences, and warning signs.

COST EFFECTIVENESS

       Costs associated with the selected remedy are dependent on the number and location of
permit requests for sediment-disturbing activities.

USE OF PERMANENT SOLUTIONS AND ALTERNATIVE TREATMENT
TECHNOLOGIES

       This action provides institutional controls  for LWBR sediment disturbance and fish
consumption advisories. Such institutional controls are necessary to protect human health and
the environment.

PERMANENT REMEDY

       This action constitutes a permanent solution. The remedial action defined in this ROD
reduces the threat to human  health and  the environment.   Monitoring will indicate whether
changes to the remedial action are needed in the future.

       The statutory preference for treatment will not be met because removal and treatment of
the contaminated soil is not a practical or implementable solution.  The implementation of the
selected alternative at the LWBR OU satisfies these requirements of CERCLA Section  121.
mSBZT.ZDH/CIE                              2-12                             September 18. I99S

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           EXPLANATION OF SIGNIFICANT CHANGES


      There are no significant changes to the chosen alternative presented to the public in the
proposed plan.
JT950327.2DH/CJE                        2-13                        Sqxember 18, 1995

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           PARTS. RESPONSIVENESS SUMMARY
JT950327.2DH/OE                                              Sqxcmber 18. 1995

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                     RESPONSIVENESS SUMMARY

      This section of the ROD documents formal public comments on the Proposed Plan for
Lower Watts Bar Reservoir made during the two public meetings or submitted in writing during
the public comment period and presents DOE's response to all comments received. The public
comment period was March 24, 1995, through April 28, 1995. A public meeting was held April
4, 1995, hi Kingston, Tennessee, and April 11, 1995, in Spring City, Tennessee, as part of the
community participation process. In addition to these public meetings, DOE has periodically was
held briefings and other meetings with public officials, special interest groups, and the public.

      This responsiveness summary  serves three purposes.  First, it informs DOE, EPA, and
TDEC of community concerns  about the site and the community's  preferences regarding the
proposed remedial alternative.  Second, it demonstrates how public comments  were integrated
into the decision-making  process.   Finally, it allows DOE  to  formally  respond  to public
comments.

      This report is prepared pursuant to the terms of the 1992 FFA among DOE, EPA, and
TDEC, as  well as other requirements, including:

      •  CERCLA as amended by SARA, 42 United States Code, Section 9601, et seq.;
      •  NCP, 40 CFR,  Part 300; and
      •  Community Relations in Superfund, A Handbook, January 1992, EPA/540/R-92/009.

      After reviewing transcripts from public meetings and written comments, DOE grouped
comments according to common issues, summarized each comment (sometimes direct quotes are
provided rather than a summary), and prepared a response to each issue and comment.

ISSUE 1:  FISH CONSUMPTION ADVISORIES

      Comment: Mark Lenox asked which species of fish are part of the fish consumption
advisories for LWBR.

      Comment: Katie Lenox  asked where the advisories are  available to the public.

      Comment: An unidentified person asked why DOE is posting fish consumption advisories
if DOE isn't responsible for the PCB  contamination.
JT9M327.2DH/CJE                             3-2                             September 18. 1995

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       Comment: Robert Cheetham asked if more recent data were available and why a more
recent fish consumption advisory brochure wasn't printed (the brochure was dated March 1992).

       Comment: Robert Cheetham also asked  if fish consumption advisory  data showed an
improvement in the PCB levels in fish.

       Comment: Carl Escabar stated "In relation to the question about the advisory, when we
sell licenses to tourists we hand out fishing regulations, or we're supposed to.  Many of us do
not because we don't want to scare our guests. The statements that were made tonight are printed
in the fishing regulations by the state of Tennessee and if you were to read them as a tourist they
would scare the hell out of you. You wonder if you should even go near the water. Now tonight
we saw on the screen a statement that said that if a thousand people were  to eat a half pound of
fish fillets for thirty years four would have a statistical probability of having a health risk.  The
question I have for the people from Tennessee is: Why is a statement like that not included in
the fish advisory so that people could make a better judgment as to whether they should stay on
Watts Bar Lake, should fish, should spend money in our community?  These  are important
things, but the state of Tennessee has been asked this question many times and has  never reacted.
My question is:  Why and when will we see something that is designed for tourists? Thank you."

       Comment: Bob McHone said that  fish advisories should be printed  more often and
shouldn't have any suppositions—only the facts.

       Comment: An unidentified person asked if smallmouth bass have been tested.

       Comment: Ernest Brakebill asked if the risk associated with consumption of catfish could
be put  into perspective by comparing it to secondhand smoke or pesticides on vegetables.

       Comment: Robert Cheetham said, "The advisories say catfish  should not be consumed.
If I caught a catfish next week and ate it would I die? That's what tourists  think when they come
in here and read this. The advisories are worded wrong and are far too conservative."

       Comment: Katherine Marsh asked why commercial fishing for  catfish is allowed if there
is a no consumption advisory in place.  She also asked how can we know that store-bought fish
are clean and safe if they are allowed to catch those fish in contaminated  lakes.

       Comment: James Talley said that the fish consumption advisories are too conservative.
He wants DOE/TDEC  to be responsible but reasonable.  He then asked if the conditions in
LWBR are better than the advisories make it seem.

nV50327.2DH/OE                              3-3                               September 18. 199S

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       Comment:  An unidentified person asked if mercury contamination of LWBR fish is a
problem.

       Response:  The TDEC Division of Water Pollution Control issued the fish consumption
advisories to fulfill the requirements of state law and keep the public informed of potential health
hazards.  There are two  types  of advisories in place for  Watts Bar  Reservoir.   A "no
consumption" advisory is in place for catfish,  striped bass, and hybrid striped bass-whitebass.
A "precautionary advisory" is  in  place to  limit consumption  of whitebass,  sauger,  carp,
smallmouth buffalo, and largemouth bass to less .than 1.2 Ib/month. Smallmouth bass have not
been tested, but a safe assumption  would be  that they contain similar contaminant levels as
largemouth bass.  The fish consumption advisories are distributed in several formats.  TDEC
issues  a brochure that describes the advisory program in full.   The advisories are listed in the
annual Tennessee Fishing Regulations, provided in the TV A publication River Pulse, and posted
on signs at major boat ramps and public fishing locations throughout the reservoir.  PCBs are the
primary contaminant  that prompted TDEC to issue these advisories.   Mercury is in LWBR
sediments, but is not concentrated in the fish tissues to the extent that it is a danger to human
health.  Data for these advisories are collected regularly. There has been little change in the PCB
levels in fish tissue.  Since the advisory has not changed, a new brochure  has not been printed
recently.  However, a new brochure/advisory may be issued in the near future.

       The advisories are based on contaminant levels and risk levels set by the U.S. Food and
Drug Administration and EPA. The contaminant levels that could cause risk to human health
have been studied for many years. Only widely accepted calculations are used to determine if
advisories are or are not needed.  The risks incurred by eating certain fish from Watts Bar are
considered involuntary. That means the consumer did not put the contamination there and has
not chosen to put himself at risk.  It is difficult to compare involuntary risk to voluntary risk like
smoking or riding a motorcycle without a helmet.  Risk numbers used to set these advisories are
total excess cancer risks. These numbers exceed the average, everyday risk of developing cancer
(1 in 6 will develop cancer on average). The state will consider comments regarding the wording
of the advisories.  DOE is not in any way in charge of the advisories currently in place.  The
preferred alternative does not provide for DOE taking over or changing  any of the existing
advisories. The advisory program is a state of Tennessee program that DOE believes is effective
in limiting consumption of contaminated fish.   The preferred alternative in this ROD is for this
program to remain in place and managed by the state of Tennessee. Changes in the wording for
these advisories must be a state of Tennessee activity. If the state of Tennessee stops the advisory
program, then DOE would consider what steps would need to be taken to protect the public from
any contaminants in fish tissue that were still a human health risk.
JT9S03Z7.2DH/CIE                               3-4                               September 18. 1995

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      The logic behind allowing commercial fisherman to harvest fish that are on the advisory
is that the risk calculated for the advisory program assumes that all the fish a person each day
for 30 years come from Watts Bar.  This risk is higher than the risk for the occasional consumer
who goes to the store and purchases fish. At the store a person would get fish from a variety of
locations and their total consumption of contaminated fish would be much lower than a fisherman
who eats only Watts Bar catfish his entire life.

ISSUE 2:  DREDGING AND CONTAMINATED SEDIMENTS

      Comment:  An unidentified person asked "What is the probability that dredging might
occur in LWBR?"

      Comment:  An unidentified person wanted to know how the sediment would be contained
if dredging were to take place.

      Comment:  Mike Swafford asked how common it was for people to dredge the lake and
use the sediments for agricultural purposes.

      Comment:  Jim Conners said he was told that EPA had to approve a dredging permit and
that it would take 5 years, so he couldn't dredge near-shore sediment at his property.  He wanted
to know if this ROD would change TV A policy.

      Comment:  Don Reed said he thought he was told previously that the worst contamination
was north of Sand Island. The new RiverPulse says that sediment quality at the dam is poor, but
it shows no other sampling locations until Kingston.  "Have contamination locations or sediment
quality changed? What constitutes poor sediment quality at the dam?"

      Response: TV A and COE records show that no dredging of deep main channel sediments
has ever occurred in LWBR.  Should  dredging be needed, the area to be dredged would be
sampled to determine if contamination was  a problem.  If that area was contaminated, special
techniques and equipment could be used to remove the sediment  without spreading too much
contamination.  Once sediment was removed, it would be disposed of in a safe place, depending
on state and federal laws. There is an interagency working group in place  among EPA, TDEC,
TV A, COE, and DOE to  review all applications for dredging  or other potential  sediment-
disturbing activities. This review is designed to protect public health and the environment from
any contamination that may be in the reservoir from past DOE activities.  This working group
forwards an opinion to TVA, COE, or TDEC, depending on which agency is  responsible for
actually approving the particular permit. The agency that approves permits does so based on the

mS0327.2DH/CIE                               3-5                               September 18. 1995

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working group opinion and other criteria, which have nothing to do with contaminated sediments.
Alterations to  floodplains  or blockage of a navigation channel  would be  typical of the
considerations for approving a permit.

       Past TV A sediment sampling occurred near the dam and near Kingston.  The data from
these samplings have remained fairly consistent throughout the years.  TV A  rated sediment
quality near the dam as poor, based on conditions such as low oxygen, high levels of ammonia,
and general poor living conditions for organisms that live on the surface sediments.

ISSUE 3: HUMAN HEALTH RISK

       Comment:  Ernest Brakebill asked if the fish could be killed and restocked to protect
human health and allow fish consumption.

       Comment: Vida Monday asked about the effects on humans harmed by the contaminants
found in LWBR, if cancer was the only effect, and if swimming or drinking the water could harm
a human.

       Comment:   An unidentified person asked about the health effects of metals  in the
sediment.

       Comment: Bob McHone asked if loggerhead turtles were safe to eat.

       Comment: Walter Lloyd asked if other laboratories besides DOE have conducted these
analyses.

       Comment: James Talley asked if there were other health risks in LWBR besides eating
fish.

       Comment: Valerie Day asked if the risks in LWBR were appreciably higher than in other
lakes.

       Comment:  The Local Oversight Committee wanted to know what the proposed plan
meant by stating that the surface water in LWBR was "relatively clean."

       Response: Killing the existing fish population in Watts Bar Reservoir would be a drastic
measure and it would be difficult for the reservoir  to recover from  such an action and difficult
to implement.  Restocked fish would eventually (within 2 or  3 years) have similar contaminant

mS0327.2DH/OE                              3-6                               September 18. 1995

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levels to the fish currently in LWBR (see response to Issue 5). Contaminants in the sediment and
water would eventually be concentrated in fish tissues.  Water coming into LWBR from the
Tennessee River and Clinch River would still contain similar contaminant concentrations. Surface
waters of LWBR are relatively clean in that contaminant  concentrations  are low enough to pass
the safe drinking water standards of state and federal laws.  There are contaminants present, but
their concentrations are very low.  Also, there may be bacterial contamination in LWBR from
cattle, septic systems, or sewage treatment plants.  Across the country, and much of Tennessee,
lakes have low levels of toxic metals, pesticides, and PCBs.  Many lakes in Tennessee and other
parts of the U.S. have fish consumption advisories in place because of PCBs in fish tissue.  There
are other lakes with more contaminated fish and other lakes with sediment contamination.

       PCBs are suspected carcinogens, so exposure at high levels over  a lifetime may result in
cancer.  Chlordane is also a carcinogen. Other than fish consumption, the risk is due to ingestion
of vegetables, meat, or milk from the agricultural use of sediments dredged out of the main river
channel (which hasn't yet occurred). The metals in these  sediments can be carcinogens or toxic.
Toxic metals can damage human kidneys, liver, central nervous system, and other organs/tissues.
The water in LWBR would not harm humans if they swam or drank the water (unless that area
was contaminated by bacteria as mentioned above).

       Turtles are thought to accumulate contaminants at about the same rate as fish, so there is
a chance that loggerhead turtles are not entirely safe to eat.

       Multiple laboratories, including an EPA laboratory, have done the chemical analyses used
to prepare the RI.  The results from all the laboratories were very similar.

ISSUE 4:  ECOLOGICAL RISK

       Comment:  An unidentified person asked what ecological health  meant.

       Comment:  Barbara Walton asked if there is a plan to reduce the uncertainty associated
with the ecological risk assessment.

       Response: Ecological health refers to the safety and well-being of animals that live in and
around the reservoir (fish, crayfish, worms, birds, mink/otter, insects, etc.). This ecological risk
assessment does not consider the impacts that these animals have on humans, but the impact that
contamination caused by humans has on the animal itself. The monitoring plan for LWBR will
allow collection of additional data that can  be  used to reduce  uncertainties associated with
ecological risk.  In addition, information from the Clinch River/Poplar Creek RI has been used

JT950327.2DH/CIE                                3-7                                Sejxnnber 18, 1995

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as a worst-case scenario for LWBR to determine if DOE contaminants are causing ecological
damage.  Should additional sampling reveal a significant  risk to the ecology posed  by DOE
contamination, EPA, TDEC, and DOE would consider further actions.

ISSUE 5: POLYCHLORINATED BIPHENYLS

      Comment:  An unidentified person asked if PCBs were a DOE contaminant.

      Comment:   Ernest Brakebill asked where PCBs in fish  tissue are coming from if the
sediment and water don't have much detectable contamination.

      Comment:  Mike Swafford asked if LWBR would continue to have PCB input.

      Comment:  An unidentified person asked if the PCBs are coming from industrial waste
or where else.

      Response: PCBs were widely used in industrial and commercial equipment until their ban
in 1976.   DOE was one of many users of PCBs around the Clinch and Tennessee Rivers.
Because of their widespread use and their tendency  to accumulate  in fatty tissue, PCBs are
routinely detected in fish samples.  PCBs are typically higher in lakes and rivers that are below
large cities or  areas where extensive electrical equipment is used.  PCBs enter the water and
sediment in extremely low levels  that are barely detectable using  today's best instruments.
Organisms that live in the water and sediment accumulate small amounts of PCBs in their tissue.
As large  organisms (such as a largemouth bass) eat these smaller animals, the PCBs begin to
concentrate and reach higher concentrations that eventually may be a risk to humans. There are
probably still small amounts of PCBs coming from the industries and cities that used to have PCB
equipment, and the PCB chemical itself was designed to last a very long time without degrading.
PCBs will continue to be a problem  throughout the world for many more years. Eventually, PCB
concentrations  in fish tissue should begin to decline.
                                             \

ISSUE 6: MONITORING AND ASSESSMENT

      Comment:  Amy Fitzgerald  asked how this ROD and the decision DOE has made will be
reassessed every 5 years, and if changing the Superfund law would alter that assessment process.

      Comment:  The Local Oversight Committee stated, "A reliance upon the DOE to fund
and help  carry out a monitoring program with a long time horizon  is questionable given that
Congress is currently assessing the functions of the  agency, as  well as substantially  reducing

JT9S0327.2DH/OE                              3-8                             September 18, 1995

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DOE's environmental management budget.  The current plan does not ensure adequate funding
for the protection of citizens' health in the  event of budgetary cutbacks,  or the possible
elimination of the DOE.

       To ameliorate this concern, it may be necessary to establish a trust fund which would
guarantee the availability of funds for long-term monitoring and other institutional controls.  The
existence of such a fund would provide assurances to down-stream residents that the agencies are
committed to the minimization of current and future risks associated with contamination stemming
from the Oak Ridge Reservation."

       Response: The FFA parties have decided that this ROD will be reviewed yearly when
monitoring plan data are provided. Even if the law changes, this legally binding document would
still require EPA, TDEC, and DOE to review the monitoring data and assess effectiveness of the
preferred alternative. Should DOE be split apart or replaced, this ROD would still be in place,
and EPA and TDEC would  require the agency that receives this portion of DOE's duties to
adhere to the requirements set forth in the ROD and in CERCLA.  By documenting this decision
in a CERCLA  ROD, DOE  is committing itself (or  DOE's  successor) to carrying out the
monitoring and assessment and providing the necessary institutional controls should TVA, COE,
or TDEC be unable to  implement their specific statutory authorities.  EPA and  TDEC are
committed to enforcing this ROD through any legal means necessary, and DOE or a successor
will be legally required to fund the DOE activities called for in  the ROD.  Federal funding from
Congress to DOE is based in  part on regulatory drivers or legal mandates. A project that DOE
is legally required to do (such as that mandated in a ROD) is given a higher priority for funds
than other projects that may not have any legal basis.

ISSUE 7: UPSTREAM AND DOWNSTREAM CONCERNS

       Comment: Mark Lenox asked when a study would be  available that presented the data
on contamination of the Clinch River,  Melton Hill, and the Emory River.

       Comment:  An unidentified person asked if this ROD  was for areas below Watts Bar
Dam.

       Response: An RI is being conducted on Clinch River,  Poplar Creek, Melton Hill, and
a portion of Emory River. Results of this investigation will be available to the public  in late
summer 1995. So far, data appear to be similar to LWBR.  This ROD was only for Lower Watts
Bar Reservoir, which begins  at Watts Bar Dam and includes the reservoir up to the confluence
of the Clinch River with the Tennessee River.

JT950327.2DH/OE                              3-9                              Septtmber 18. 1995

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ISSUE 8:  OTHER CONCERNS

       Comment:  Don Richardson asked about the TV A aquatic plant management program on
Watts Bar and upstream.

       Response:  Vegetation has declined throughout the system in recent years.  During the
mid- to  late-1980s there was little rain—the low  flow  and turbidity allowed greater  light
penetration and plants grew much  faster and in  areas  they hadn't previously grown.  Plant
eradication was necessary in some instances to maintain navigation.  No spraying was done on
Watts Bar last year and none is planned for this year.  Natural conditions have eliminated the
need for weed control. Spraying for weeds is only done when necessary. Upstream reservoirs
have little weed growth and have not been sprayed.

       Comment:  An unidentified person asked if anything regarding this decision will be placed
in local papers.

       Response:  Community relations is an important part of CERCLA projects and DOE
activities. Public notices and meetings have been ongoing for this project.  Further mention of
this project in the papers during the coming years  is likely.

       Comment:  Barbara Walton asked if the risk for sediment disturbance has been assessed
in the event of a 100-year rain and breakage of the dam.

       Response: These activities were assessed during the RI/FS process. A 100-year rain has
occurred during the past two decades, and sampling  indicates  there was little  sediment
disturbance.  A heavy rain would tend to bring silt from the local land and streams into the
reservoir rather than scour the existing sediments from the bottom of the reservoir. In the event
of a dam failure, damage to the environment and the loss of life would result from flooding rather
than contamination.  The sediments that wash downstream during a dam failure would  be spread
over a wider area; therefore, concentrations of contaminants would decrease. Direct exposure
to these sediments is not a significant health threat, and the only scenario of concern would still
be the growing of crops or cattle on farmland composed entirely  of Watts Bar main channel
sediments.  The contaminated sediments  would be  spread over a wider area  in diluted form and
would not pose a risk to human health in the event of a dam failure or  100-year rain.

       Comment:  Barbara Walton suggested  that  longer comment periods  should be provided
for public review of complex documents.


mS0327.2DH/OE                              3-10                               Sqxonber 18. 1995

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       Response:  The public review period that DOE provides is mandated by CERCLA and
is legally required to be no less than 30 days.  The comment period for this proposed plan was
36 days. However, this comment will be considered for future actions.

       Comment:  The Local Oversight Committee asked how the cost effectiveness of the
alternatives could  be compared if a formal cost estimate of the preferred alternative was not
prepared.

       Response:  The cost of active removal or containment of sediments over the majority of
the main channel in LWBR was estimated to be $30-40 billion. The  cost associated with the
other agencies' institutional controls and advisories cannot be determined.  Cost will depend on
the particular situations that occur in the permitting of sediment-disturbing activities. The main
portion of the cost that DOE will be responsible for is the implementation of a monitoring
program.  The approximate cost of the annual monitoring is $1.5 million. Administrative cost
for the lAG-coordinated activities has not been determined.

       Comment:   The Local Oversight Committee asked if the Meigs County executive and
DOE can meet to discuss the implementation of this preferred alternative.

       Response:  DOE would be happy to meet with anyone who desires to do so at a mutually
convenient time.

       Comment:  An unidentified person said that he thought the public meeting  was a good
one.

       Comment:  Barbara Walton said that she was in general agreement with the preferred
alternative.

       Response:  Thank you very much.

LETTERS RECEIVED FOLLOWING THE COMMENT PERIOD FROM C. S. SANFORD

Letter  Dated April 5, 1995

       Comment:  What was the developed alternatives time period of  analysis?

       Response:  Based on the questions that follow, we suspect that you are asking if there
were distinct time  periods over which the advantages or improvements  of each alternative were

JT9S0327.2DH/CIE                              3-11                             Sqxember 18. 1995

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measured as compared to some other criteria, such as no action.  In the case of LWBR, there are
no such time periods involved.  According to standard EPA guidance, alternatives are judged first
on their effectiveness in protecting human health and the environment, then on other criteria. The
goals are to reduce or eliminate exposure to contaminants, not to estimate effect over time. The
latter is a component of risk assessments.

       Comment:  Was  a cost-benefit analysis or capital investment plan used?

       Response:  A cost-benefit relationship is built into the risk analysis process performed
under CERCLA.  Risk action levels for a particular contaminant reflect a cost-benefit decision.
Please  refer to Chapter 5 in the LWBR RI/FS.

       Comment: What was the period of costs? What was the period of health effects? (20, 50,
or more years?)

       Response:  The  answers  to these  questions vary with  the contaminant  and with the
exposure scenario.  Specific periods are listed individually in Chapter 5 of the LWBR RI/FS.

       Comment: Are there health risk estimates which approach the half-life of the endangering
toxics?

       Response:  None of the contaminants of concern have  a "half-life" because none are
radioactive.

       Comment:  Is EPA's intent to remove dredging as a viable alternative?

       Response: The responsibility for future activities on LWBR rests with DOE and DOE
does not  consider dredging a viable alternative at this time.  EPA and TDEC must concur with
DOE's decision.  EPA  strongly supports  the use of institutional  controls for this portion of
LWBR contamination.

       Comment:  Does the law require  a preference for permanent treatment of the toxics?

       Response: All other things being equal, CERCLA specifies a preference for permanent
treatment.  However, it is a preference, not a requirement.  In the case of LWBR,  treatment
would  create short-term  elevation in risk and environmental impacts that outweigh the long-term
risk reduction.
JT950327.2DH/CJE                               3-12                               September 18, 1995

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       Comment: Is EPA's preference in contradiction to permanent treatment?

       Response: For reasons explained in the FS and proposed plan, DOE's preference does
not include permanent treatment.  EPA concurs.

       Comment: Is it EPA's position that "No Action" will prevent off-site migration of the
toxics?

       Response: The chosen alternative for LWBR is not "no action." It is DOE's position that
the chosen alternative will prevent risk to the public from the contaminants present in LWBR
sediment,  and EPA concurs.

       Comment:  Is  it EPA's position that natural events will not disrupt the present river
bottom and its layer of contaminated mud.

       Response: There is no evidence that natural processes have significantly disturbed the
contaminants deposited in the 1950s, and there is  no evidence that future disturbance will occur.

       Comment: Is it EPA's conclusion that the Clean Water Act has no legal authority over
the off-site contamination?

       Response: EPA believes that DOE has met  or exceeded all requirements of the Clean
Water Act  [33 U. S. C. Sect. 1251], CERCLA, and the National Contingency Plan with respect
to the pending decision for LWBR.

       Comment: Does EPA know of drinking water supplies located on this river body?

       Response: There are three.  All test their water in accordance with state and federal
requirements.  None show any indication of ORR-related contaminants.

       Comment: Did EPA utilize  any computer models for clean-up alternatives?

       Response: No. Modeling studies of individual sites  is not pan of EPA's role in the
CERCLA  process. However, Lockheed Martin Energy Systems, a contractor  to DOE, used a
one-dimensional model to estimate aspects of sediment transfer in LWBR.  Please refer to page
3-70 of the LWBR RI/FS.
JT9S0327.2DH/CIE                               3-13                              September 18, 1995

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       Comment:  Was active bottom transport of mud for streambed over-burden considered a
positive or negative benefit?

       Response:  Please refer to Chapter 5 in the LWBR RI/FS.

       Comment:  If a computer model was used, then what was the time period of consideration
and were seasonal variations used?

       Response:  Please refer to Chapter 5 in the LWBR RI/FS.

       Comment:  Did any computer model utilize a time period which included the " 100 year
flood" or its counter-part, the 100 year drought?

       Response: Yes. The model was used to estimate the effects of a localized  100-year storm
and a regional 100-year storm.

       Comment:  Does any computer model have the capability to analyze the results of a flash
flood during a drought?

       Response:  Although such modeling might have some value on land or in small feeder
streams,  reservoirs are controlled bodies of water that have neither flash floods nor droughts.
Please see previous question on high-water events.

       Comment:  Were epidemiological studies used which placed a weighing factor on groups
involved in water recreation as being more at risk than other groups?

       Response: CERCLA uses an assessment of potential risk process rather than conducting
epidemiological surveys in determining potential threats of contaminants to human health. Please
refer to Chapter 5 of the LWBR RI/FS, particularly pages 5-14 through 5-16.

       Comment:  Does the annual average dose of toxics include probabilities of occurrence for
specific upset conditions which could affect the water recreation user community?

       Response:  To allow for such variations in exposure, the CERCLA risk  process selects
a relatively high value (reasonable maximum exposure) to ensure that the risk assessment results
approach the worst-case exposure possible from the contaminants.
TT950327.2DH/CJE                              3-14                               September 18. 1995

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      Comment:   Is  it EPA's  position that DOE's miscellaneous discharge of radioactive
materials into the non-radiological treatment plant is a safe practice?

      Response:  DOE does not discharge to local treatment plants. All DOE discharges are
regulated by local, state, and federal laws.

      Comment:  Does EPA know of any law which prohibits this practice from polluting the
navigable waterways?

      Response:   The Clean Water Act prohibits the discharge  of  certain pollutants into
navigable waters. However, ORR conforms to all CWA regulations and is regulated by NPDES
and other discharge requirements.

      Comment:   Does the EPA have knowledge  of COE's comments on dredging cost
estimates?  Does EPA have records of requesting COE comments on dredging activity for the
cost study?

      Response: COE was provided the opportunity to review the drafts of the RI/FS, proposed
plan, and ROD.

      Comment:  Does EPA believe that COE is qualified in giving cost estimates for dredging?

      Response: COE is one of many groups capable of preparing an appropriate cost estimate
for dredging LWBR.

Letter Dated May 22, 1995

      Comment:   (To Victor Weeks) Would you please supply information that  addressees
proposals that would reduce health risks over the projected life-of-the-plant of Watts Lake with
consideration of the time constraints for natural de(cay?) of the radioactivity?

      Response:  Please refer to Chapter 5 of the LWBR RI/FS.

      Comment:  Does EPA possess the definitive and all-inclusive model or does it exist on
a Martin Marietta/DOE main-frame or super-computer on the DOE reservation at ORNL?

      Response:  No.  Modeling  studies of individual sites is not  part of EPA's role in the
CERCLA process.  However, Lockheed Martin Energy Systems, a contractor to DOE, used a

JT9SQ327.2DH/CJE                             3-15                              September 18. 1995

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one-dimensional model to estimate aspects of sediment transfer in LWBR.  Please refer to page
3-70oftheLWBRRI/FS.

       Comment: Presuming that the models portray increasing sophistication and accuracy for
decision making,  then what  role  does  your office have  in  recommendations  for  model
improvement or for rejection of results?

       Response:  The model  used  for LWBR provided useful information,  but decisions on
alternatives are only based in small part on the results of such models. The principal basis for
such decisions is risk assessment. Please refer to Chapter 5 of the LWBR RI/FS.

Letter Dated July 7, 1995

       Comment: 1 must presume that there are 10,000 Ac-ft to be dredged. Is this a continuous
operation or are  there  several mobilization requirements  with  intermittent and seasonal
constraints.

       Response: Dredging would be more or less continuous until the remediation is completed.
Obviously, many movements of equipment would be  necessary to dredge the entire reservoir.
The estimated time to complete the work through the final disposal of the sediments was over 20
years.

       Comment: Does your referenced one-dimensional "computer" model have a variable river
flow rate for a constant-mass or constant-volume unit  of measure?

       Response: Please refer to page 3-70 in the LWBR RI/FS.

       Comment:  It was my understanding that there was contamination down to a three foot
mud depth; so,  was the "depth of 2 ft" just a generalization, an average thus implying different
depths; hence,  an extant hydro survey.

       Response: The 2-ft depth was used as a general estimate of the overall  volume involved
in the  dredging approach.  Many areas will have no  sediments or contaminants.   The actual
depth that would be required would be determined during the  initial phase of the work.

       Comment: How accessible is the Oak Ridge Environmental Information System database?
JT950327.2DH/CJE                              3-16                              September 18. IMS

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       Response:  Currently, there is no mechanism for the public to directly access the Oak
Ridge Environmental Information System (OREIS). Eventually, the state of Tennessee will have
direct access and will serve as a conduit for public access.  Hard copy data are available as part
of the administrative record file and can be retrieved as needed.   The DOE OREIS staff can
process specific electronic requests. Some reimbursement of costs incurred in handling data may
be required.

       Comment:  Do fields (i.e., matrices) of computer information, as discussed above, exist
on the referenced database (previous sentence)?

       Response:  Data from the LWBR study are currently on the data base.

       Comment:  Are there any plans to evaluate the conditions as discussed in the main body
of this letter? Computer models for four dimensional analysis of sediment deposition and the use
of these models to compare costs of  alternatives.

       Response: This level of modeling  is not required for this site. Sufficient information for
assessment of risk is available  from other sources.  Please  refer to Chapter 5 of the  LWBR
RI/FS.

       Comment:   What have been  the time periods  of analysis for computer or manual
calculations?

       Response:  For the sediment transport modeling,  1991 to 2021.  Please see page 3-70 in
the RI/FS.

       Comment:  Have these calculations or any cost-benefit calculations included: loss of use,
reserved contingencies, impairment of use, secondary positive economic activities, etc.?

       Response:  These  factors are not involved in the sediment transport model.

Letter of August 18, 1995

       Comment:   Re.   OREIS database;   does  this database supply information to other
databases (e.g., EPA CIS, etc), especially regarding off-migration of pollutants?

       Response:  Not at present.
JT9503Z7.2DH/OE                               3-17                               September 18. 1995

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       Note:  A meeting was held September 14,  1995, in Oak Ridge, Tennessee, to discuss
certain aspects of the Clinch River/Poplar Creek/Lower Watts  Bar environmental restoration
program. Mr. Sanford attended and he was briefed and questions were answered by DOE, EPA,
TDEC, Lockheed Martin Energy Systems, and Jacobs ER Team.  Mr. Sanford feels that there
are many issues regarding the process followed in reaching the decision (the CERCLA process)
that need to be addressed.  All of the meeting participants agreed to continue responding to his
requests  for information and answering his questions as best possible; however, this document
will continue onward for regulatory approval.
JT9S0327.2DH/CIE                              3-18                               September 18. 1995

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                               REFERENCES
EPA (U.S. Environmental Protection Agency). 198S. Handbook Remedial Action At Waste
      Disposal Sites (Revised), EPA/625/6-85/006, Office of Emergency and Remedial
      Response, Washington, D.C.

EPA. 1989. Exposure Factors Handbook, EPA/600/8-89/043, Office of Health and
      Environmental Assessment, Washington, D.C.

TVA (Tennessee Valley Authority). 1987. Watts Bar Reservoir Land Management Plan.
      (Final Draft).  Knoxville, TN.

TVA. 1990. Tennessee River and Reservoir System Operation and Planning Review, Final
      Environmental Impact Statement, TVA/RDG/EQS-91/1.  Knoxville, TN.
JT9503Z7.2DH/OE                            3-19                            September 18, 1995

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