PB95-964008
EPA/ROD/R04-95/215
March 1995
EPA Superfund
Record of Decision:
Savannah River Site (USDOE)
(Par Pond Unit), Aiken, SC
2/13/1995
-------
United States Department of Energy
Savannah River Site
. Interim Action Record of Decision
Remedial Alternative Selection (U)
Par Pond Unit
WSRC-RP-93-1549
Revision 0
January 26, 1995
Westinghouse Savannah River Company
Savannah River Site
Aiken, South Carolina 29808
~OMSIBlLll
~'" ".
. q. 05'",
.~ ~~
4.«, iF; -=-,;-::;, ~
~ .. -.-. ......
c;,;, ...... -,., -..... ",/.
-- -
'WI -~ ...
...._~....
~ --~
SAVANNAH RIVER SITE:
PREPARED FOR THE U.S. DEPARTMENT OF ENERGY UNDER CONTRACT' DE-AC09-89-SR18035
-------
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
INTERIM ACTION RECORD OF DECISION
REMEDIAL ALTERNATIVE SELECTION (U)
Par Pond Unit
. Savannah River Site.
Aiken. County, South Carolina
Prepared by:
u.s. Department of Energy
Savannah River Operations Office
Aiken, South Carolina
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26. 1995
DECLARATION FOR THE INTERIM ACTION RECORD OF DECISION
Unit Name and Location
Par Pond Unit
Savannah River Site
Barnwell County, South Carolina
The Par Pond unit, consisting of the Par Pond Reservoir, the series of pre-cooler ponds arid
canals, and Lower Three Runs Creek, at 'the Savannah River Site (SRS), is listed as a
Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) unit in
Appendix C of the Federal Facility Agreement (FFA).
Statement of Basis and Purpose
This document presents the selected interim remedial action for the Par Pond operable unit, defined
as the approximately 1340 acres of sediment!> at the periphery of the Par Pond Reservoir that were
exposed as a result of the drawdown of the reservoir from 200 ft to 181 ft mean sea level (msl).
The interim action was developed in ~ordance with CERCLA of 1980, as amended, and to the
extent practicable, the National Oil.and Hazardous Substances Pollution Contingency Plan (NCP).
This decision is based on the Administrative Record File for this specific CERCLA unit.
Assessment 0/ the Unit
Par Pond is a 2640-acre man-made reservoir constructed to augment the cooling water
requirements of both P and R Reactors of SRS. Releases in the form of pr<><;ess leaks, purges,'
and makeup cooling water have contaminated Par Pond sediments with cesium-137' and other
radioactive and nonradioactive contaminants. During an inspection of Par Pond Dam in March
1991, a small surface depression waS noted on the downstream face. Based on the inspection
report, the U.S. Department of Energy (OOE) ordered a detailed structural investigation into the
cause of the depression and simultaneously initiated a precautionary drawdown of the Par Pond
Reservoir from the original 200 :t 1 ft to 181 ft ms!. The 181-ft level was chosen to reduce the risk
and consequences, in the unlikely event of a dam failure, of potential flooding in downstream
communities. The drawdown resulted in exposure of approximately 1340 acres of previously
submerged sediments contaminated with cesium-137 and other radioactive and nonradioactive
contllrUnants; . .
Remedial alternatives were developed for interim remediation of the exposed sediments caused by the
reservoir drawdown. The alternatives developed are based on limited existing information regarding
the physical and chemical characteristics of the sediments of Par Pond and the hazardous substances
within the sediment. OOE is conducting ongoing investigations of the Par Pond waste unit. The
additional information being obtained is essential in developing technically effective remedial
alternatives that would address all contaminated media and risk. Regarding the
remediation/restoration of Par Pond, OOE is scoping a phased approach to identify the optimal
sequence of investigative activities and unit actions. An interim action is initially being proposed to
remediate the immediate potential'risks caused by exposure of contaminated sediments due to
reservoir drawdown including associated efforts upon the reservoir, due to erosion of exposed
sediments. A CERCLA Remedial Investigation (RI) characterization is currently planned according
to the FF A schedule.
Description 0/ the Selected Remedy
The preferred interim alternative consists of refilling and maintaining Par Pond to the original 200
:t I-ft level following repair of the Par Pond Dam. Based on comments on the Interim Action
Proposed Plan for the operable unit,. the preferred alternative has been modified to include
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP..,93-1549, REV. 0
JANUARY 26, 1995
maintenance of the reservoir at the 200-ft water level until a National Environmental Protection Act
(NEP A) evaluation can be accomplished of the environmental impacts from reduced flow to Lower
Three Runs Creek (the creek below Par Pond Dam), fluctuating reservoir water level, and the
discontinuance of providing river water, through pumping, to the reservoir.
The preferred 'alternative is an interim action. A final action(s) will be evaluated following
implementation of the preferred interim action alternative according to the FF A schedule. The
interim action provides the most timely reduction of risk to human health and the environment
through submergence of the sediments with a layer of water upon restoration of the Par Pond water
level. The water layer would attenuate gamma radiation emitted from the decay of cesium~ 137 and
minimize the potential for sediments to become airborne. Also, of significance to the environment,
the interim action would allow for a gradual recovery of the reservoir to essentially pre-drawdown
ecological conditions.
'Declaration Statement
The interim action remedy is protective of human health and the environment, complies with
Federal and South Carolina applicable or relevant and appropriate requirements (ARARs) directly
associated with this limited scope action, and is cost-effective. This' interim action utilizes
permanent solutions and alternative treatment (or resource recovery) technologies, to the maximum
extent practicable, given the limited scope of the action. Because this action does not constitute the
fmal remedy for the Par Pond unit, the statutory preference for remedies that employ treatment that
reduces toxicity, mobility, or volume as a principal element, although partially addressed in this
remedy, will be addressed by the final response action(s). Subsequent actions are planned to
address fully the threats posed by the conditions "at the Par Pond unit. Since this is an Interim
Action Record of Decision, review of this unit and of this remedy will be ongoing through
implementation of the Remedial Investigation and Feasibility Study process required in accordance
with the terms of the FFA as DOE, the U.S. Environmental Protection Agency, and the South
Carolina Department of Health and Environmental Control continue to elop medial
alternatives for the Par Pond unit .
I /'36 /9~
~I
/
Frank McCoy .
Assistant Manager for Environment,
Safety, Health, ~d Quality
2. - / :3 -q~
Date
~M~
r- John H. Hankinson, Jr.
Regional Adrilinistrator
U.S. Environmental Protection Agency
Region IV
2.-/b' '7.S
Date
I?~~.~
R. Lewis Shaw
Deputy Commissioner
Environmental Quality Control
South Carolina Department of Health and
Environmental Control
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
Section
I.
II.
III.
IV.
V.
VI.
VII.
VIII.
IX.
X.
XL
XII.
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
. DECISION SUMMARY
T ABLE OF CONTENTS
Pa2e
Site and Operable Unit Names, Locations, and Descriptions... """""""""" 1
Operable Unit History and Compliance History.... "'" """ ......... ..... ........, 1
Highlights of Community Participation.,.. . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . , . . . . . . .. 7
Scope and Role of Operable Unit within the Site Strategy ...... ....,.... "" ....... 8
Summary of Operable Unit Characteristics......... """ .,""'" ....,. .., ...... ....10
. .
Summary of Operable Unit Risks .~..... ,.. ....., """'" """ ... ........, ..........10
Description of Alternatives[[[ ....16
Summary of Comparative Analysis of Alternatives. .,......,.,.. ...... .., """"" 22
. Selected Remedy.. . ., . . . . " . . . . .. '.' . . .. .. . . .. . . . . .. . . . . . . . . . .. . .. . . .. , . . ., . . . . .. . . . . . .. . 23
Statutory Detemrination.................................,............,... ................24
Explanation of Significant Changes. . . . . . . . . . . . . , . . . .. . . . . . . . . . . . , . , , . . . . . ., . . . . . . . . . . 24
References.. .. , . . .. . . .. .. . . . . , .. ... , . . .. . . , , . .. .. , . .. . .. . . . . . , , ., . . . . .. . . . ,. . . . . . . , . . .. .. . 25
. List of Fieures
Figure 1.
Figure 2.
Figure 3.
Figtire 4,
Figure 5.
Location of Par Pond in Relation to Major SRS Facilities
The Par Pond CERCLA Waste Unit
2
3
Operable Unit for the :J:nterim Action at the Par Pond Waste Unit
. Sampling Locations for Data Used in the Limited Qualitative Risk
Assessment of Par Pond Exposed Sediments
9.
11
Proposed Flow for Par Pond Refill
14
List of Tables
Table.l.
12
Appendix
A.
-------
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
DECISION SUMMARY
INTERIM ACTION
REMEDIAL AL TERNA TIVE SELECTION
Par Pond Unit
Savannah River Site.
Aiken County, South Carolina.
Prepared by:
U.S. Department of Energy
Savannah River Operations Office
Aiken, South Carolina
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
1.
Site and Operable Unit l\ame,
Location, and Description
The Savannah River Site (SRS) occupies
approximately 300 square miles of land adjacent
to the Savannah River, principally in Aiken and
Barnwell Counties of South Carolina (Figure
1). SRS is a secured U.S. government facility
with no permanent residents. The Site is located
approximately 25 miles southeast of Augusta,
Georgia, and 20 miles south of Aiken, South
Carolina. According to 1990 census data, the
average population densities (in people/square
mile) for the surrounding South Carolina
counties are 111 for Aiken County, 36 for
Barnwell County, and 28 for Allendale County,
and for the surrounding Georgia Counties are
228 for Columbia County, 524 for Richmond
County, 25 for Burke County, and 21 for
Screven County. The population within a 50-
mile radius of SRS is 635,000 people.
SRS is owned by the U.S. Department of
Energy (DOE). Management and operating
services are provided by Westinghouse
Savannah River Company (WSRC). SRS has
historically produced tritium, plutonium, and
other special nuclear materials for national
defense. SRS has also provided nuclear
materials for the space program and for medical,
industrial, and research efforts. Chemical and
radioactive wastes are by-products of nuclear
material production processes. Hazardous
substances, as defmed by the Comprehensive
Environmental. Response, Compensation, and
. Liability Act (CERCLA), are currently present
in the environment at SRS. The Par Pond unit,
consisting of the Par Pond Reservoir, the series
of pre-cooler ponds and canals, and Lower
Three Runs Creek, is listed as a CERCLA unit
in Appendix C of the Federal Facility Agreement
(FF A, 1993). For the purposes of this interim
action, the operable unit addressed consists of
the approximately 1340 acres of sediments at the
periphery of the Par Pond Reservoir that were
exposed as a result of the drawdown of the
reservoir from 200 ft to 181 ft mean sea level
(ms!).
Par Pond is a 2640-acre man-made reservoir
located northeast of P Area and east of R Area
in the eastern portion of SRS (refer to Figure 1).
WSRC-RP-93-1549, .REV. 0
JANUARY 26. 1995
Par Pond was created in 1958 bv constructing
an earthen dam across Lower"' Three Runs
Creek. The three main arms of the reservoir
follow the uppermost portion of Lower Three
Runs Creek and its former tributaries, Poplar
Branch and Joyce Branch (Wilde and Tilly,
1985). Prior to drawdown, the elevation of Par
Pond was 200 :t 1 ft IDS!. The current elevation
after drawdown is 181 ft IDS!. Prior to
drawdown, Par Pond had a mean depth of
approximately 20 ft, a maximum depth of
approximately 60 ft near the Par Pond Darn, and
a shoreline length of approximately 38 miles
(Wilde, 1985). .
The easternmost shore. of Par Pond lies.
approximately 1.5 miles from the eastern SRS
boundary. The southern shore of the reservoir
lies approximately 200 ft north of Road B. Par
Pond discharges through controlled releases into
Lower Three Runs Creek, which in turn
discharges into the Savannah River. The length
of Lower Three Runs Creek from the outfall of
Par Pond to the Savannah River is
approximately 20 miles.
Operable Unit History and
Compliance History
Operable Unit History
II.
Par Pond was built to augment the cooling
water requirements of both P and R Reactors
(Wilde, 1985). R Reactor began operations in
1953. Prior to construction of Par Pond, R
Reactor received cooling water directly from
the Savannah River and discharged cooling
.water directly into Lower Three Runs Creek in
an area that is now the Hot Arm of Par Pond
(Figure 2). P . Reactor began operations in
1954. Prior to construction of Par Pond, P
Reactor received cooling water directly from
the Savannah River and discharged cooling
water directly into Steel Creek.
During the late 1950s, an effluent pathway was
constructed from R Reactor to Par Pond. The
pathway consisted of the R Canal and Pond B
(Figure 2). This effluent pathway was used for
R Reactor discharge from 1961 until the reactor
w.as shut down in 1964. Since the shutdown
. of R Reactor in 1964, R Canal and Pond B
have remained mostly undisturbed. Par Pond
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
SOUTH
CAROLINA
SOUTH
CAROLINA
Figure 1. Location of Par Pond in Relation to Major SRS Facilities
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
NORTH ARM
- N-
I
(CA. 20 MILES FROM
PAR POND OVERFLOW
TO SAVANNAH'R[V£R)
SAVANNAH RIVER
LEGEND
INTAKE LINES
PRE-COOLER CANALS
LOWER THREE RUNS CREEK
PAR PQNO RESERVOIR
PRE-COOLER PONDS
SCALE IN MILES
Figure 2. Operational Scheme of Par Pond Cooling and Discharge System
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT'
also served as a heat exchangelcooling
reservoir for P Reactor until 1988. Heated
water from P Reactor was released through a
series of manmade canals and smaller
impoundments into the. pre-cooler Pond C.
The effluent from Pond C passed through a
. concrete culvert below an earthen dam (the
Pond C Dam) and was funneled by gravity into
the Hot Arm of Par Pond.
Releases in the fonn of process leaks, purges,
and makeup cooling water have contaminated
Par Pond with cesium-137 and other
radioactive and nonradioactive contaminants.
BetWeen 1954 and 1964, approximately 222
curies of cesium-137 were' released ,from R
'Reactor into Par Pond or Lower Three Runs
Creek (before the creation of the reservoir in
1958). All radioactive isotope releases ceased
following the shutdown of R Reactor in 1964.
No measurable cesium-137 was released into
Par Pond from P Reactor (Wilde, 1987).
Concentrations of radioactive isotopes in Par
Pond have decreased due to the cessation of
reactor releases. decay of the isotopes, dilution
from groundwater seepage, and seepage losses
from' the basin. Since most of the radionuclide
releases to Par Pond (directly or indirectly)
occurred during the 1950 to 1960 era. and the
. half-life of cesium-137 is approximately 30
years, more than half of this radionuclide has
decayed. The current esrim~too inventory of
cesium-137 associated with all sediments
within the Par Pond reservoir is approximately
43 Ci (Winn, 1993), of which 9 Ci are present
in the 1340 acres of exposed sediments. The
remaining 68 Ci of cesium-137 inventory in the
Par Pond system is located in the sediments of
the pre-cooler canal/pond system and Lower
Three Runs Creek.
Mercury has .been detected in fish from the
Savannah River. and SRS waterbodies since the
analyses began in 1971, with comparable
concentrations measured in onsite and offsite
fish (WSRC, 1991a). It had been assumed that
much of the mercury detected in onsite fish
reflected mercury present in Savannah River
water which originated primarily from
industrial releases upriver from SRS. This
water has been used as cooling water in site
facilities and then discharged to SRS streams
and lakes.
WSRC-RP-93-1S49, REV. 0
JANUARY 26. 1995
Since 1989, concentrations of mercury in fish
collected at all locations onsite have been hieher
than fish collected from the Savannah RIver
(WSRC, 1991 a). Therefore, concentrations of
mercury may not be totally attributable to
offsite sources. SRS is currently investigating
possible causes for these increased concen-
trations.
Since 1980, the Par Pond Dam has been
inspected every other year. In addition to these
inspections, wet areas near the downstream
slope of the embankment have been inspected
annually (DOE, 1992). During an inspection
of the Par Pond Dam in March 1991, a smaIl
surface. depression was noted on the
downstream face. Based on the inspection
report, DOE ordered a detailed structUral
investigation into the cause of the depression
and simultaneously initiated a precautionary
drawdown of the reservoir. From June
through September 1991, the level of Par Pond
was lowered from 200 :t 1 ft to 181 ft ms!.
The 181- ft level was chosen to reduce the risk
and consequences, in the unlikely event of a
dam failure, of potential flooding in
downstream communities.
Limited studies have been conducted to
. evaluate the ecological effects of the continuing
drawdown of Par Pond (DOE, 1993). Results
of these ongoing studies are summarized
below.
Lowering the surface water level elevation of
Par Pond from a full.pool of approximately 200
ft to 181 ft msl resulted' in a reduction' of the
reservoir's surface area and volume by
approximately 50 and 65 percent, respectively.
This action caused many changes in what had
been a. formerly hydrologically stable and
biologically productive ecosystem (Whicker et
al., 1993). The drawdown of the reservoir had
two major repercussions: (1) the elimination of
the previous littoral (shore) zone and its
interrelated communities, and (2) the exposure
of sediments. contaminated particularly with
radiocesium and mercury. All components of
the Par Pond ecosystem are continuing to
undergo a period of disequilibrium associated
with a readjustment to new conditions within
the basin. The ecosystem is recovering, but at
much reduced population sizes compared to ftill
pooL
~
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
The loss of approximately two-thirds of the
original volume of Par Pond and exposure of
1340 acres of lakebed sediment resulted in
temporary impacts to the reservoir's water
quality. Effects of the increased erosion and
sediment resuspension from the exposed
lakebed caused an increase in turbidity of the
reservoir's water column. Erosion gullies up
to approximately 11 inches deep were cut by
individual rainstonn events during the fall of
1991 and the winter of 1991-1992 because of
the initial lack of vegetative cover on the
exposed lakebed (Whicker et al.. 1993).
However, colonization of the former lakebed
by terrestrial and semi-aquatic plant species has
stabilized. much of the exposed sediment,
thereby reducing the impacts of erosion and
runoff. As a result of this reduction in the
sediment loag into the basin, the turbidity has
. decreased significantly compared to that
immediately following the drawdown, and
water clarity is presently similar to pre-.
drawdown conditions.
The dissolved ion concentrations in Par Pond
were historically maintained as a result of a
history of recirculation, evaporation, and
Savannah River water inputs. The termination
of pumping make-up water from the Savannah
River has resulted in a decrease of ions to the
Par Pond ~cosystem. The conductivity of the
surface waters was reduced from
approximately 80-100 J.lIIlhoslcm to 30
J.1.I11boslcm by the. drawdown.. After the
drawdown, the relatively large influence of
groundwater and natural surface inputs. which
are very low in dissolved ions. began to
dominate the water chemistry of the basin
(Whicker et al., 1993). . Associated with these
reduced dissolved ion concentrations, increased
levels of radiocesium have been found in
muscle of largemouth bass suggesting
increased biological mobility of radiocesium
and possibly other contaminants in the
reservoir (Whicker. 1991; DOE, 1993). .
Approximately 1.5 square miles of submergentl
emergent wetland vegetation were lost as an
immediate result of the drawdown of Par Pond.
However, a number of species of aquatic plants
have colonized the new littoral zone and
shallow areas of the reduced area of the
reservoir. This vegetation reestablishment was
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
both rapid and extensive. The revegetation of
the protected coves was more extensive than in
open, wave-washed areas. Mo~t of the new
shoreline was colonized by either emergent or
submergent aquatic vegetation. Eurasian
watermilfoil, water-lily, slender naiad, and
cattail were the four most common species
(Whicker, 1992a). .
The exposed sediments have exhibited a rapid
vegetative colonization similar to that observed
in some new shoreline habitats. The most
common terrestrial plant species, in descending
order of percent cover, are bog rushes,
maidencane, bulrush, dog fennel and a sedge
species (Whicker. 1992a). The colonizing
vegetation on the exposed sediment is a mix of
wetland and old-field plants, depending on soil
moisture. Moisture varies with distance from
the new shoreline, topography, soil type, and
the presence of seeps.
Garden plot studies involving the propagation
of cultivated plants on the exposed sediments
were undertaken to evaluate the rate of
radiocesium mobilization into food crops.
Based on these studies. the uptake of
radiocesium is extremely high for the amounts
of that radionuclide available in the soil. . This
also would be expected to be reflected in the
tissues of those anima)~ species which forage
on this successional vegetation (Whicker.
1992a; 1992b).
One of the most noticeable impacts resulting
from the exposure following the drawdown of
the reselVoir was the decimation of many beds
of freshwater mussels and clams (Whick~r,
1991; DOE, 1992). However, current
observations on Par Pond indicate that these
populations appear to be recovering in the
reduced area reservoir.
Par Pond fish populations were temporarily
reduced as a result of the drawdown. The
absence of an established linoral zone was
expected to have the potential for a total loss of
recruitment, because of reduced spawning and
nursery habitat. In general, although
recruitment was reduced during 1992, limited
sampling data indicate that most species,
including some short-lived forage. species.
. experienced some recruitment. This occurred
5
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
in spite of the loss of the original linoral zone
and probable intense predation. .
As noted previously, the conductivity of the
water in the Par Pond Reservoir has decreased
following the drawdown and tennination of the
pumping of make-up water from the Savannah
River. As the potassium ion decreases in
availability, organisms take up more
radiocesium, which is a potassium analog and
more readily available in this now potassium-
poor water. The impact of this has been
observed in the increasing body burden of
radiocesium in Par Pond largemouth bass.
Other fish species would be expected to have.
similar concentrations (Whicker et al., 1993).
There is no evidence that the drawdown
adversely affected the winter survival of adult
alligators in Par Pond. Unfavorable conditions
for nesting,. and habitat conditions (lack of
cover) that have undoubtedly resulted in the
low survival of juveniles, have probably been
the most important impacts of the reservoir
drawdown on this resident alligator population.
In general, the waterfowl use of Par Pond
during the wintering season has been reduced
due to the physically smaller area and reduced
food resources. The numbers of. birds
overwintering on the reservoir during the
second year following the drawdown had
increased compared to the winter of 1991;
however, these numbers are still below pre-
drawdown levels. This increase in the
waterfowl numbers is at least in part due to the
recovered levels of the aquatic macrophyte and
invertebrate populations in the basin. In
addition, the radiocesium body burdens in the
ducks Uicreased. during the second winter with
forty percent of the adult birds having
measurable levels of radiocesium. .
Substantial numbers of mourning dove have
been observed foraging on the vegetation
which has colonized the exposed lakebed.
Concern for the potential off-site transport of
contaminants by these birds prompted an
analysis of birds found feeding on the
terrestrial plants inhabiting the old lakebed
versus birds collected off-site. These studies
have shown that there are detectable levels of
both mercury and radiocesium in the birds
WSRC-RP-93-1549. REV. 0
JANUARY 26. 1995
foraging on the exposed lakebed; however.
these body burden levels do not pose a concern
for human consumption at this time. Although
there is no evidence of harm to wildlife from
uptake of Cs-137 or mercury, there has been a
noticeable increase in the uptake of cesium in
some of the animals and vegetation on the
sediments. The uptake levels have not yet
reached a dose level where harm to wildlife will
occur. The longer wildlife is .exposed or can be
exposed to the sediments, the greater the uptake
of contaminants will be and the greater the risk
of physiological. harm becomes. Wildlife
monitoring will continue.
Par Pond has beeri and contj.nues to be the
location where most sightings of bald eagles on
the SRS takes place (Mayer et al., 1985; 1986;
WSRC, 1993). Observations of both adult and
immature birds on Par Pond have continued to
be infrequent but persistent. In general, the use
. of the reservoir by bald eagles has been for
both foraging and roosting activities. The
drawdown has had no noticeable impact on the
bald eagle use of Par. Pond. It is assumed that
most of the prey obtained. by bleeding adults
and newly-fledged immatures is obtained in
and around Par Pond. The impact of the use of
Par. Pond prey (primarily largemouth bass) by
both adult and immature bald eagles is
unknown at this time.
The sightings of golden eagles on the SRS
continue to be a rare event. There have been no
more observations of this species using Par
Pond since the sightings during the winter. of
1991 (WSRC, 1993).
Compliance History
At SRS, waste materials are managed which are
regulated under the Resource Conservation and
Recovery Act (RCRA). Certain SRS activities
have required Federal operating or post-closure
permits under RCRA. SRS received a
hazardous waste permit from the South Carolina
Department of Health . and Environmental
Control (SCDHEC) on September 30, 1987.
Part V of the permit mandates that SRS establish
and implement a RCRA Facility Investigation
(RFI) Program, to fulftll the requirements
specified in Section 3004(u) of the Federal
permit. On December 21, 1989, SRS was
6
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
placed on the National Priorities List (NPL). A
site placed on the NPL comes under the
jurisdiction of CERCLA. In accordance with
Section 120 ofCERCLA, DOE has negotiated a
FFA with the U.S. Environmental Protection
Agency (EPA) and SCDHEC to coordinate
cleanup activities at SRS into one compre-
hensive strategy that fulfills RCRA Section
3000(u) and CERCLA assessment, investi-
gation, and response action requirements. . The
Par Pond unit is listed as a CERCLA unit in the
FFA.
On July 17, 1991, DOE notified EPA-Region
IV and SCDHEC that possible dam failure at
Par Pond could be an imminent and substantial
endangennent to public health, safety~ and the
environment under CERCLA, Section 104
(WSRC, 19~1). DOE and EPA viewed the
draw down of Par Pond as a removal action
under Section 300.415 (d)(3) of the National Oil
and Hazardous Substances Pollution
Contingency Plan (NCP). Subsequent
evaluations indicated that repair activities to
stabilize the dam were. necessary (Bechtel,
1991). As a result, DOE determined that the
appropriate action. to ensure safety was. to
maintain the reservoir at the 181-ft elevation.
This action would facilitate repairs and reduce
potential for impacts to downstream
communities in the unlikely event .of a dam
. failure. Repair of the dam was approved under
a CERCLA 106 Abatement Action Letter
(WSRC, 1991). In conjunction with the
technical evaluation of needs for the. dam, DOE
performed several environmental analyses
including a Special Environmental Analysis for
Par Pond at the Savannah River Site (DOE,
1992), to comply with National Environmental
Policy Act (NEP A) requirements and
commitments, which evaluated the impacts of
drawdown, repair of the dam. and refill back to
the 200-ft.level. As of July 1, 1994, the Par
Pond Dam has been repaired and is considered
safe to maintain the. reservoir at pre-drawdown
water levels. .
An agreement was reached with EP A - Region
IV for SRS, under the site evaluation process of
CERCLA, to conduct a limited, qualitative
human health risk assessment concerning the
sediments exposed from the drawdown of Par
Pond (WSRC, 1992). This human health risk
WSRC-RP-93-1549. REV. 0
JANUARY 26, 1995
assessment identified potential for additional
exposure and the need to evaluate alternatives
for reducing that exposure. In addition. an
assessment of environmental risks based on
existing infonnation was also performed
(WSRC, 1992; DOE, 1993).
In addition to cesium-137, mercury has also
been identified as a chemical of concern (COC)
in Par Pond exposed sedimer:tts although the
concentrations and extent of contamination have
not been fully assessed. Ecological studies
indicate potential threats from cesium-137 and
mercury in the sediments to animal receptor
species (WSRC, 1992).
For an interim action and as requested by EPA-
Region IV, DOE evaluated interim action
remedial alternatives to reduce potential risks
associated with cesium-13? in the exposed
sediments. Based on current data, the most
critical concerns for evaluation of interim
remedial alternatives for the Par Pond sediments
are the control of risks due to cesium-137
contamination. An evaluation of alternatives to
support a fmal action will be .conducted
following .completion of this interim action and
an RI/FS for the entire waste unit.
Highlights of Community
Participation
Public participation requirements are lis~ed in
Sections 113 and 117 of CERCLA. These
requirements include the establishment of an
Administrative Record File that documents the
selection of cleanup alternatives and provides
for review and comment by the public of those
alternatives. The SRS public involvement plan.
(DOE, 1994) is designed to facilitate public
involvement in the decision-making processes
for pennitting, closure, and the selection of
remedial alternatives. The SRS public
involvement plan addresses the requirements of
RCRA, CERCLA, and the National
Environmental Policy Act (NEPA). Section
117(A) of CERCLA, 1980, as amended,
requires the preparation of a proposed plan as
part of the site remedial process. The Interim
Action Proposed Plan for the Par Pond Unit
(IAPP) (WSRC, 1994), which is part of the
Administrative Record File, highlights key
aspects of the assessment and investigation
III.
7
-------
INTERIM ACTION RECORD OF DECISION
PA R POND UNIT .
phases of the remediation process and identifies
the preferred interim action alternative for
remediation of the Par Pond unit.
The Administrative Record File, which contains
the infonnation pertaining to the selection of the
response action, was made available at the EP A-
Region IV office and at the following locations:
U.S. Department of Energy
Public Reading Room
Gregg-Graniteville Library
University of South Carolina-Aiken
171 University Parkway
Aiken, South Carolina 29801
(803) 641-3465
Thom~ Cooper Library
Government Documents Department
University of South Carolina
Columbia, South Carolina 29208
(803) 777-4866 .
Similar information was made available through
the following repositories: .
Reese Library
Augusta College
2500 Walton Way
Augusta, Georgia 30910
(404) 737-1744
Asa H. Gordon Library
Savannah State College
Tompkins Road
Savannah. Georgia 31404
(912) 356-2183
The public was notified of the comment period
for the IAPP through mailings of the S R S
Environmental Bulletin. a newsletter sent to
more than 1400 citizens in South Carolina and
Georgia, and through notices in local
newspapers including the Aiken Standard, The
State, and the.Augusta Chronicle.
The public comment period began on December
1, 1994 for the IAPP and ended on January 6,
1995. Responses to comments are discussed in
the Responsiveness Summary (Appendix A).
A public meeting was held on December 14,
1994 in Aiken, South Carolina to discuss the
WSRC-RP-93-1549. REV. 0
JANUARY 26. 1995
selected interim action remedy. Wrinen and oral
commentS. were accepted during this meeting.
These comments are addressed in the
Responsiveness Summary (Appendix A).
IV. Scope and Role of Operable Unit
within the Site Strategy
This interim action operable unit addresses only
the remediation of approximately 1340 acres of
sediments on the periphery of the Par Pond
reservoir that were exposed as a result of
reservoir drawdown (Figure 3). The overall
strategy of remediating the Par Pond waste
unit, consisting of the Par Pond reservoir, the
series of pre-cooler ponds and canals, and .
Lower Three Runs. Creek,. is to: (1) perform
the proposed interim action described herein;
(2) further characterize the waste unit
delineating the nature and extent of
contamination and identifying the media of
concern; (3) perform a quantitative baseline risk
assessment to evaluate media of concern,
chemicals of concern, exposure pathways and
characterize potential risks; and (4) evaluate and
perform a final action to remediate the identified
media of concern. The operable Unit described
in this Interim. Action Record of Decision
(!ROD) does not include the submerged
sediments in Par Pond. the series of pre-cooler
ponds. or Lower Three Runs Creek. The
discrete action of this operable unit constitutes
the fIrst of the proposed strategies which would
address the immPr1jate threats posed by the
overall waste unit. The interim action would
remediate the. immediate potential risks caused
by exposure of CODtamin~ted sediments due to
reservoir drawdown. . the action fulfills the
qualitative interim remedial goals by proViding
the most timely reduction of risk to human
health and the environment through
submergence of the sediments with a layer of
water upon restoration of the Par Pond water
level. The water layer would attenuate gamma
radiation emitted from the decay of cesium-137
and minimize the potential for contaminated
sediments to become airborne or to become
further redistributed through erosion. Also, of
significance to the environment, the interim
action would allow for a gradual recovery of
the reservoir to essentially pre-drawdown
.ecological conditions. Following the
performance of this interim action, further
8
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP.93~1549, REV. 0
JANUARY 26, 1995
~
LEGEND
-
INDICATES 181 FT. MSL
INDICATES 200 FT. MSL
~
- N-
~
OPERABLE UNIT 11340 ACRES
OF EXPOSED SEDIMENTS)
-
PRECOOLER
POND C
NORTH
ARM
SOUTH
ARlo!
Figure 3. Operable Unit for the Interim Action at the Par Pond Waste Unit
9
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
characterization, and perfonnance of the risk
assessment a fmal action(s) will be evaluated
which w~uld address residual risk or
contamination for the entire waste unit.
Summary of Operable Unit
Characteristics
The lowering of Par Pond from 200 ft to 181 ft
exposed approximately 1340 ac~s of se~ent
on the periphery of the reservOIr con~~
with radionuclides and nonradioactIve
contaminants. Data are limited for evaluation
of human health and environmental risks
associated with the exposed sediments.
Sampling locations for data used in the limited,
qualitative risk assessment of Par Pond
sediments are identified in. Figure 4. The
limited, qualitative risk aSsessment identified
16 nonradioactive constituents in Par Pond
sediments (fable 1). The risk assessment
screening process resulted. in ~e selectio~of
five of these constituents, banum, berylhum,
cadmium. chromium, and mercury, for further
evaluation in the huIIian health risk assessment.
These chemicals generally exceeded
background concentrations and thus ~arran~ed
a risk evaluation. For the ecological nsk
assessment, mercury was selected as the. focus
because the levels of mercury found m the
sediments suggested a pote~tial hazard t~ biota
living on the exposed sediments and m the
associated aquatic communities, and because. of
its bioaccumulation and biOconcentratIon
potential. .
Four radionuclides, cesium-137,cobalt-60,
plutonium-238, and plutonium-239, were
detected in Par Pond sediments (fable 1). All
of these radionuclides were considered as
chemicals of potential concern in the human
health risk assessment. However, for the
ecological risk assessment, only cesium-137
was evaluated because it comprised the largest
percentage of the radioisotope inve.ntorr, was
present in the. greatest concentratton in the
sediments, and because it has a tendency for
bioaccumulation and bioconcentration.
v.
Decay of cesium-137 is b~ beta particle
emission (7%) and through banum-137 X-rays
(low-energy gamma radiation, 85%). .The X-
rays resulting from the decay of ceslUm-137
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
associated with the exposed sediments pose the
primary external radiation exposu!'e route. In
addition, exposed sediments contairiing
cesium-13 7 (and other radionuclides) could
potentially become airborne through wind or
other natural activities. Inhalation of airborne
sediments is also considered a potentially
significant exposure route.
Since most of the radionuclide releases to Par
Pond (directly or indirectly) occurred during
the 1950 to 1960 era, and the half-life of
cesium-137 is approximately 30 years, more.
than half of this radionuclide has decayed. The
current estimated inventory of c~sium-13 7
associated with all sediments within the Par
Pond reservoir is approximately 43 Ci (Winn,
1993), of which 9 Ci are present in the 1340
acres of exposed sediments. The remaining 68
Ci of cesium-137 inventory in the Par Pond
system is located in the sediments of the pre-
cooler canaVpond system and Lower Three
Runs Creek. The maximum concentration of
cesium-137 in exposed Par Pond sediments is
656,640 pCi/kg (WSRC, 1992). The exposed
sediments are contained in an . area of
approxiInately .1340 acres on the periphery of
the Par Pond reservoir. The majority of the
contamination is within the top one foot of the
sediment (Whicker, 1991). This gives a
volume of. sediment potentially requiring
remediation of approximately 2.2 million cubic
yards. .
VI.
Summary of Operable Unit Risks
Human Health Risks
Existing human populations that potentially
may be exposed to operable. .unit-rel~d
contaminants include residents livmg outsIde
but near the eastern boundary of SRS or
downstream in the Lower Three Runs Creek
and Savannah River watersheds, trespassers
who may enter the Par Pond area, and workers
involved with ongoing activities at Par Pond.
Exposure pathways through which human
receptors could potentially be exposed include
external exposure to radiation from eXI?Osed
sediments inhalation of airborne sedIment
particulate's, and dermal con~t with and
inoestion of sediments. Lowenng the level of
P~ Pond to 181 ft has exposed approximately
10
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
_h
- --~_/ ...../.-...-
~
PUMPHOUSE ./
/
/
I
/1
I
I
I
(CA. ~O MILES FROM
PAR POND OVERFLOW
TO SAVANNAH RIVER)
PAR POND RESERVOIR SYSTEM
SAVANNAH RIVER
DATA COLLECTION REFERENCES
o
... DuPONT. 1987
. FLEDDERMAN. 1991
SCALE IN MILES
WINN. 1993 (TRANSECT DATA)
Figure 4. Sampling Locations for Data Used in the Limited Qualitative Risk Assessment of
Par Pond Exposed Sediments
II
~
- N- .
~
2
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26. 1995
Table 1. Maximum Concentrations of Chemicals in Par Pond Sediments Compared to
Background Levels
Contaminant
Maximum Concentration
Background Levels
Aluminum 22,400 mglkg . 10,000-300,0001 mglkg
Barium 500 mglkg 1102 mglkg
Beryllium 3.99 mglkg 0.6222 mglkg
Cadmium 2.37 mg/kg <0.00012 mglkg
Calcium 2040 mglkg 7000-500,0001 mg/kg
Chromium 49.3 mglkg 8.442 mglkg
Copper 10.2 mg/kg 2-1001 mglkg
Iron 30,500 mglkg 7000-550,0001 mglkg
Lead 9.33 mglkg 2-2001 mglkg
Magnesium 608 mglkg 600-60001 mglkg
Manganese . 297 mglkg 20-30001 mglkg
Mercury 0.614 mglkg 0.2892 mglkg
Nickel 5.69 mglkg 5-5001 mglkg .
Silver 0.0713 mglkg 0.2932 mglkg
Sodium. 17.0 mglkg 750-75001 mglkg
Zinc 43.1 mglkg 10-3001 mglkg
Cesium-137 656,640 pCi/kg <2()()()2 pCi/kg
Cobalt-6O 770.0 pCi/kg <4()()()2 pCi/kg
Plutonium-238 4.09 pCi/kg NA3 .
Plutonium-239 38.0 pCi/kg, NA3
Source:
WSRC, 1992
. 1 Lindsay, W.L., Chemical Equilibria in Soils
2 Meyer's Branch Data
3 NA = Not available
12
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
1340 acres of sediments that were previously
under water. If no remedial action is taken,
this sediment would remain exposed. A limited
risk assessment was conducted (WSRC,
1992), based on limited existing data to address
the human health risks resulting from these
exposed sediments and forms the basis of the
current understanding of human risk for the
remedial action alternatives.
The data were not collected to fulfill the strict
data quality assurance and quality control
requirements of a CERCLA baseline risk
assessment (WSRC, 1992). Therefore this
risk assessment evaluates the data by
identifying current and future exposure
conditions which provide a range of potential
risks from exposure to Par Pond contaminants.
In addition, the risk assessment only evaluates
the contaminants identified from the existing
data. Other contamin"ants may be present in the
Par Pond sediments, but without a
comprehensive sampling and analysis effort,
the risks resulting from exposure to all
contaminants cannot be adequately assessed.
Because of the qualitative nature of the risk
assessment, attempts to model contaminant
transport were considered inappropriate.
Extrapolation of exposure point concentrations
using data that were of a quantity and quality
inappropriate for model input, was considered
to introduce" an unacceptable level of
uncertainty in the modeling results. An
exception to this approach was made regarding
resuspension to air of sediments no longer
covered by surface water, which was
considered the pathway most likely to transport
appreciable quantities of contaminants from Par
Pond during the drawdown condition. For this
pathway, modeling was conducted using
existing data to estimate" exposure con-
centrations of cesium-137 for current off-Par
Pond unit locations (Hamby 1991b; Marter and
Carlton, 199.1).
Carcinogenic risks from inhalation of airborne
sediment particulates by residents outside SRS
boundaries were found to not be a concern, as
the estimated risk is less than the EP A target
risk range of I x 10-6 (one excess cancer in one
million people). As stated above, risks were
WSRC-RP-93-1549, REV. 0
JANUARY 26. 1995
not calculated for residential exposure (outside
SRS boundaries) through ingestion of surface
water containing resuspended sediments.
However, estimates of the annual dose
equivalent of cesium-137, noted during" the
drawdown of Par Pond, suggested that risk
from this pathway would be negligible.
Introduction of cesium-137 to Lower Three
Runs Creek and the Savannah River through
erosion of exposed sediments during refIll is
not likely to exceed the amount that was
introduced during drawdown. The Par Pond
Dam Reservoir Refill Plan calls for refIlling the
Par Pond by pumping water from the Savannah
River to the Par Pond, using the existing P-
Reactor intake piping and" discharge canal, at
rates of 80,000 to 160,000 gallons per minute
(gpm). The plan will transfer 50,000 gpm
down P-Discharge Canal to the Hot Arm, and
the remainder will be pumped by reversal of
normal flow through the Par Pond Pump
House Station, located at the head of the South
Arm (Figure 5). "The potential for
remobilization of contaminated sediments in the
Par Pond drainage during refill has been
calculated (Chen, 1994). Particular emphasis
has been given to the potentiaI for loss of
contaminated sediments from Par Pond into
Lower Three Runs Creek. Calculations show
that sediments would not be resuspended at the
Pond C Dam (Hot Dam) outlet to the Par Pond.
Sediments. would be resuspended around the
Par Pond Pump Station area. However, most
of the suspended sediment would settle before
reaching the Par Pond Dam. A very small
quantity of sediment might remain in
suspension. Although some sediment may be
released, the downstream impact from cesium-
137 will be far less than that experienced
during the drawdown. During drawdown,
water was released at 240,000 gpm (versus
10,000 during refIll) and the amount of cesium-
137 and suspended solids amounted to a
maximum of 8 percent of the drinking water
standards.
Carcinogenic risks calculated for the current
land use scenario indicate only one pathway,
external exposure from sediment to the Par
Pond unit worker, exceeds the EP A-established
target risk of 1 x 10-6; the risk for this pathway
" is calculated to be 4 x 10-5, within the EPA
13
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
POND
V
PAR PQNO V
PUMPHOUSE-T
STATION X'
-, i;
\ -z i
\ o.
—i
/ ^—^PUMPHOUSES
JS^—^M^-—
NORTH ARM
LOWER
THREE
RUNS
CREEK
"ff (CA. 20 MILES FROM
PAR POND OVERFLOW
TO SAVANNAH RIVER )
SAVANNAH RIVER
LEGEND
REFILL FLOW DIRECTION
PR£-COOLER CANALS
P~j LOWER THREE RUNS CREEK
INTAKE LINES
gigjgj PAR POND RESERVOIR
^H PRE-COOLER PONDS
SCALE IN MILES
Source: Wilde, 1985
Figure 5. Proposed Flow for Par Pond Refill
14
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
target risk range. By managing work
conditions and duration, this risk can be
minimized.
Carcinogenic risks calculated for the hypo-
thetical future Par Pond ,unit worker and future
Par Pond unit resident exposed to Par Pond
sediments indicate that risks exceeding the
EP A-established target range of 1 x 10-4 to 1 x
10-6 are likely for these scenarios. Because of
the hypothetical nature of the Par Pond unit
resident scenario, the additional pathways that
are identified by this scenario are not likely to
be of concern in the immediate future.
However, the results of this scenario do
identify additional pathways of concern should
the Par Pond unit resident conditions become a
possibility.
The limited risk assessment indicated no
adverse noncarcinogenic human health effects
are likely from exposure to Par Pond
sediments.
Environmental Risks
A limited, qualitative ecological risk assessment
(WSRC, 1992) was conducted to determine the
potential effect of exposure to contaminated
sediment on the newly emerging (early-
successional) terrestrial community inhabiting
the 1340 acres exposed from the drawdown of
Par Pond to 181 ft. Because the exposed
contaminated sediments can erpde into Par
Pond, potential risks to the aquatic community
also, were addressed. The ecological risk
assessment investigated only current conditions
at Par Pond. Neither the impact from the
drawdown on the Par Pond ecosystem nor the
potential effect from selected remedial
alternatives were evaluated.
Two biotic communities were assessed for
exposure to contaminants in the exposed Par
Pond sediments, an early-successional
terrestrial community and the aquatic Par Pond
community potentially exposed from erosion of
the exposed sediments into the reservoir. Biota
from both populations are potentially exposed
to radionuclides and non-radioactive
constituents. Of the four radionuclides known
to be present in Par Pond sediments. only
cesium-137 was addressed in this assessment.
WSRC-RP-93-1549. REV. 0
JANUARY 26, 1995
Cesium-137 comprised the largest percentaoe
of the radi.onuc,lide inventory, had the great~t
concentratIon In the sediments, and has a
known propensity for bioaccumulation and
bioconcentration. There were 16 non-
radioactive constituents identified in the
sediments of Par Pond. of which only mercury
was chosen as a chemical of potential concern
due to its tendency for bioaccumulation and
bioconcentration.
Of the species known to inhabit or visit the
exposed sediments of Par Pond and the Par
Pond aquatic ecosystem, the following were
chosen as receptor species for the assessment:
.
Rare, threatened, or endangered species
[bald eagle, wood stork, American alligator
(due to similarity of appearance to an actual
threatened or endangered species which can
be considered threatened or endangered by
comparison)] ,
Potentially affected sport or commercial
species (white-tailed deer, ring-necked
duck, largemouth bass, bluegill, loblolly
pine) .
Species that represent obvious and known
toxicological endpoints for exposure (water
lotus" water lilies, wild pig, brown water
snake, slider turtle, American coot,
bufflehead, homed grebe, lesser scaup,
ring-necked duck, and ruddy duck)
Species that control the community
structure and function through predation
(American alligator, largemouth bass, 'and
wild pig) .
Species' that demonstrate marked
productivity and abundance (blackbeny
briar and rush) .
.
.
.
.
All selected terrestrial animal species, may
experience possible ecological effects from
exposure to cesium-137. In addition. the
American alligator may experience adverse
ecological effects from, mercury exposure
(WSRC, 1992). .
All selected aquatic animal species may
experience adverse ecological effects from
exposure to mercury, while the bald eagle,
wood stork, and American alligator also may
experience possible adverse effects from
cesium-137 exposure.
15
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
Results of the limited risk assessment indicate
that cesium-13? and mercury levels in the
exposed sediments potentially threaten the
animal receptors that inhabit the Par Pond
shoreline with maintenance of the reservoir at
the 181-ft msl water level. However, little or
no effects to' either terrestrial or aquatic
vegetation are expected to occur. Effects of
cesium-13? and mercury contamination from
the exposed sediments that are transported to
the reservoir in runoff will be specific for each
receptor species depending upon such factors
as diet and metabolism. If significant loading
of sediment to the reservoir Was to occur,
e~~ts from cesium-137 are expected to be
~fl1ma1. However, enhanced mercury .loading
mto the basin, in addition to causing the
potential for increased methylation processes,
pose.s threats- to the identified aquatic receptor
species and the Par Pond ecosystem. This is
especially true for the fIsh-eating protected
species (i.e., bald eagle, wood stork, osprey,
and American alligator).
Based on observations and fIeld evidence (e.g.,
tracks and scats), the use of the exposed
lakebed by a few species of lI'I3mm31~' has
continued since the drawdown. This primarily
includes the wild pig and white-tailed deer.
Both of these species are harvested during the
fall public hunts on the SRS. Because of this,
these roammals are a concern associated with
the uptake of contaminants (e.g., radiocesium)
through the human consumption of ~nimals
taken in the area around Par Pond. Increased
levels of radioeesium concentrations in wild pig
muscle over pre-drawdown levels has
occurred, likely due to these anim~J~ rooting in
the con,taminated sediments. Although higher
than observed .prior to the drawdown, these
levels do not currently pose a concern for
human consumption. Although there is no
evidence of harm to wildlife from uptake of Cs-
13? or mercury, there has been a noticeable
increase in the uptake of cesium ~ some of the
animals and vegetation on the sediments. The
uptake levels have not yet reached a dose level
where harm to wildlife will occur. The longer
wildlife is exposed or' can be exposed to the
sediments, the' greater the uptake of
contaminants will be and the greater the risk of
physiological harm becomes. Wildlife
monitoring will continue. Extensive rooting in
WSRC.RP.93.1549, REV. 0
JANUARY 26, 1995
the lakebed sediments by the wild pigs around
Par Pond began immediately after the
drawdown and continues to be extensive. The
drawd~wn appears to have facilitated the range
expansIOn of the SRS wild pig population in
the area of Par Pond. This range expansion
would be expected to result in damage to areas
which had not previously been subjected to
depredation by this non-native species. In
addition, it also brings the distribution of these
animals closer to the SRS boundaiy, increasing
the po~ential for the off-site transport of
contanunants and harvest by local residents.
VII. Description of Alternatives
Remedial al~ernatives were developed for the.
. Par Pond umt for the reduction of human health
and environmental risk from cesium-13?
contamination in the exposed sediments. In
accordance with the NCP, the No Action
Alternative was set forth as a baseline. The
alternatives are as follows:
Alternative 1
No Remedial Action and Maintain Par Pond at .
the 181-ft Level' .
Alternative 2
Refill and Maintain Par Pond at the 200:!: I-ft
Level
The preferred alternative for the Par Pond unit
is Alternative 2 - Refill and Maintain Par Pond
at the 200:!: I-ft Level
Alternative 1 involves no remedial action for
. the exposed sediments. Alternative 1 consists
of leaving Par Pond at the 18t-ft level.
Al.te~ve 2 involves refilling Par Pond to the
ongmal 200 :!: I-ft level and maintaining the
reservoir at that level.
Alternative 1 - No Remedial Action and
Maintain Par Pond at the 181-ft Level
Under Alternative 1, Par Pond sediments
would be left in place and no remedial efforts
would be conducted. . Par Pond would remain
at the 181-ft level, leaving 1340 acres of
contaminated sediments exposed. Currently,
. approximately 10 cubic feet per second of
reservoir water is discharged to Lower Three
16
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
Runs Creek te maintain bieta cemmunities in
the creek. Because .of current access centrels
at SRS, the potential human health impacts
wauld be te Par Pend unit werkers frem
external expesure te radienuclides in the
sediments; ingestien .of and dermal. centact with
the sediments; and inhalatien expesure te
airborne particulates inside SRS beundaries.
These potential impacts can be centrelled by
management .of werk cenditiens and duratien.
Alsa, engeing revegetatien .of the exposed
sediments result in reductien in particulate
materials beceming airberne. The wetland and
aquatic habitats .of the Par Pend. ecesystem
. weuld net recever te pre-drawdewn
c.onditi.ons. Instead, terrestrial habitat w.ould
. eventually bec.ome fully established an the
appr.oximately 1340 acres .of exp.osed sediment.
Exp.osure .of animal recept.ors t.o the
c.ontaminated sediments weuld c.ontinue.
Further descripti.on .of this alternative appears
bel.ow.
Treatment C.omponents. Ne treatment w.ould
be implemented.
Engineering Controls. No engineering c.ontrols
w.ould be required.
Instituti.onal Controls. Access to SRS is
centrolled at primaIy r.oads by continu.ously
manned barricades. Other roads entering the
site are closed to traffic by gates or barriers.
The entire SRS facility is surrounded by an
exclusion fence, except al.ong the Savannah
River.. The Site is posted against trespassing
under state and Federal statUtes.. No
. additi.onavIiew controls weuld be institUted. .
Quantity of Waste. The contaminants are
primarily located within the tep .one foot of
sediments. Under Alternative 1, approximately
1340 acres of sediment weuld remain exposed
until fInal action(s) is evaluated. Censidering
that the depth of contaminatien does net exceed
.one faet, the v.olume .of c.ontaminated sediment
is appr.oximately 2.2 millien cubic' yards.
Implementation Requirements. This alternative
is readily implementable.
Estimated Constructien and Operatien and
Maintenance C.osts. Ne remedial c.osts are
WSRC.RP-93-1S49, REV. 0
JANUARY 26, 1995
expected far implementatien .of this alternative.
. Dam repair casts are n.ot addressed in this
IAPP. Maintenance c.ostS include pumping!
discharge cests ta maintain the water level in
Par Pend at the 181-ft level. This cest is
estimated t.o be $280,000 annually. The cest is
an incremental (estimated) cost (part .of the t.otal
c.ost) associated with the operation .of the Site
Cooling Water Distributien System (river water
system) that maintains water t.o Par P.ond, L
Lake, and the react.ors. The river water system
will remain in service, at this time, regardless.
.of the acti.on chasen fer Par Pend. Theref.ore,
SRS would still incur the cost associated with
the .operation .of the pumps. . A review of
remedy must be c.onducted every five years, as
required under the Superfund Amendments and
Reauthorization Act (SARA). Costs include
estimates .of meetings with EP A every five
years using current overhead, wages, and
expenses. A present w.orth factor is applied t.o
the cost at a disc.ount rare of five percent.
Inflation is considered t.o be zero percent. The
present worth c.osts for pumping/discharge. to
. maintain the reservoir water level and remedy
review extended .over a. 3D-year period would
be, respectively, approximately $4,300,000
and $280,000, .or a total of approximately
$4,600,000.
ARARs ASsociated with the Considered
Alternative. Applicable or Relevant and.
Appropriate Requirements (ARARs) are
Federal and state environmental regulations that
establish standards .which remedial actions
must meet. There are three types of ARARs:
(1) chemical-specific, (2) location-specific, and
(3) action-specific. . This section sets forth
major ARARs associated with the remedial
~te~ve. .
There are. no chemical-specific .or action-
specific ARARs associated with Alternative. 1.
The single locati.on-specific ARAR associated
with Alternative 1 is the Endangered Species
Act (16 USC 1531 et seq.). The Act is
intended to prevent the further decline .of
endangered anq threatened species and t.o bring
about the restorati.on of these species and their
habitats. Section 7 of the Act requires
c.onsultation with the Department of the Interior
regarding any ~ti.on of a Federal facility that
may impact endangered .or threatened species.
17
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
The Department of Interior is a Natural
Resources Trustee for SRS. As such, their
advice is continuously sought and they are kept
informed on environmental issues, including
the proposed interim action at Par Pond. The
Endangered Species Act is applicable to the
interim action since endangered (bald eagle)
and threatened [American alligator (due to
similarity of appearance to an actUal threatened
or endangered species)] species utilize Par
Pond. These predator species utilize the
reservoir and could be adversely affected by the
increased loading of contaminated sediments
from runoff into the basin and subsequent
uptake and accumulation. by prey species
(WSRC, 1992). Both species also can be
adversely affected by preying on terrestrial
animals livi.r;1g on the exposed contaminated
sediments. The wood stork is not considered
to be impacted by the interim action as this
species does not regularly utilize Par Pond.
During the initial stages of reservoir
drawdown, wood storks were seen feeding on
prey isolated in shallow pools formed along the
shoreline by receding waters~ However,
. subsequently as the water level dropped and the
isolated pools dried out. the sloping shoreline
became steeper in gradient and the habitat
became unsuitable for use by wood storks.
This species requires a shallow water habitat
such as found in nearby Kathwood Lake. The
Endangered Species Act is the only law or
regulation that includes the potential impacts to
individual organisms from exposure to
chexnicals in the exposed ~ents. Other
laws or. regulations that deal with potential
impacts to namral resources relate to physical
disturbance rather than chemical effects. The
proposed interim action does not include
physical disturbance, and, accordingly are not
ARARs. Floodplain. manaeement and
wetlands protection regulations are not ARARs
because the Par Pond reservoir is not itself a
jurisdictional wetland. Jurisdictional wetlands
are present in the original streambed of Lower
Three Runs Creek below the Par Pond Dam
(CDE, 1987).
Alternative 2 - Refill and Maintain Par
Pond at the 200 ~ I-ft Level
Alternative 2 involves refilling the Par Pond
reservoir and maintaining at the 200 :t I-ft
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
level, su~merging currently exposed sediments
with water. The wetland and aquatic habitats
of the Par Pond ecosystem would eventually
recover to essentially pre-drawdown
. conditions. Because of the access controls at
SRS, the only temporary exposure pathway
would be to workers at the Par Pond unit
directly exposed to the sediments. External
exposure to radionuclides, ingestion of and
dermal contact with sediments, and inhalation
of airborne sediments would cease with the
refilling of Par Pond.
Since its construction in 1958, the Par. Pond
reservoir on the SRS has historically been a
highly productive and diverse ecosystem
benefiting from the protection from disturbance .
afforded by its location on the SRS. In spite of
contaminants introduced from SRS production
reactor effluents (e.g., heat. radionuclide
discharges) and Savannah River water (e.g.,
mercury), the reservoir ecosystem has. shown
high biological diversity and has been an
important regional resource for waterfowl.
. Primary production in the reservoir has been
stimulated by inputs of . nitrogen and
phosphorus from Savannah River water that
was used to replace seepage and evaporative
losses, and to maintain constant water levels.
The historic. inputs of Savannah River water
have resulted in the accumulation of chemical
constituents in the basin. Mercury
accumulation has been documented, and, while
not documented, .nitrogen and pho$phorus
accumulations are also expected to have
occurred. These constituents have accumulated
primarily in sediments and, to a lesser extent,
in biota in the ecosystem. Similarly, inputs of
radionuclide releases from R Reactor have
accumulated primarily in the sciliments.
The refilling of Par Pond will significantly
mitigate the risks associated with direct
exposure frOm contaminated sediments. Once
refilled, the overlying water will effectively
shield the gamma radiation emissions from the
cesium-l.37. Additionally ,'potential risks from
resuspension by wind, although cwrently low,
will be eliminated. The rate at which this
mitigation is achieved is solely dependent on
the time at which the reservoir is refilled to its
historic water level of 200 ft msl.
18
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
The refilling of the reservoir will represent a
significant additional change for the Par Pond
ecosystem and will have both transient and
pennanent effects, relative to current and
previous conditions. The refilling action will
result in three inunediate stresses to the Par
Pond ecosystem. Additional nutrients
(nitrogen and phosphorus) will be introduced
into the basin with Savannah River water.
Significant ponions of the nutrients currently in
the exposed sediments and the vegetation
growing on these sediments will also be
remobilized into the water column following
inundation. This influx of nutrients is expected
to result in . eutrophic to hypereutrophic
,conditions in the reservoir (i.e., exceptionally
. high algal abundance and possible shifts to
. undesirable algal species). Introduction of
nutrients during the spring and summer months
is expected to result in worse conditions than if
these. nutrients are introduced during the fall
and winter months when water temperatures
and light intensity are lower. The presence of
nutrients introduced during the winter months
and mobilization of nutrients from sediments
and decaying vegetation during the growing
season makes the development of eutrophic to
hypereutrophic cQnditions unavoidable, but
II1inimi7~tion of nutrient input during the spring
and summer months may afford SOme
mitigation for this condition.
A second stress will. result from inundation of
the vegetation on the exposed sediments.
Decay of this vegetation will deplete dissolved
. oxygen in the overlying water. To the ,extent
that the inundation and initial decay occurs
during the winter months, this sttess may be
somewhat mitigated ba--aIJ~ decomposition
rates will be lower, more oxygen will be
. available in the colder water, and oxygen
requirements by fish and other aquatic
organisms will be lower. Nevertheless, it is
anticipated that the zone of oxygenated water
will be significantly reduced during at least the
first year following reservoir reml from late
spring through early fall.
The third stress resulting from the ref1l1 will be
habitat disruption. Over the three years of the
drawdown, the linoral (shore zone) community
has become reestablished in the reservoir,
although at a much reduced size compared to
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
historic conditions. This littoral zone supports
aquatic plant. aquatic invertebrate, and fish
communities that are dependent upon this
shallow water habitat. Of panicular. importance
is the use of this habitat for fish spawning and
as a nursery area for juvenile fish. This habitat
. will be lost during the refill and full
reestablishment of the littoral zone habitat will
require several years following refill of the
reservoir and stAbilization of y.rater levels.
Some mitigation of the potential impacts on fish
populations can be obtained by stabilizing
water levels during the fish spawning and
nursery periods. By maintaining relatively
stable water levels during the spring. and
summer, fish are expected to. complete
spawning and recruitment. Should the
reservoir not achieve its final pool level during
the initial period of refilling, the reservoir water
level will be stabilized to maximize the chances
for successful spawning during 1995. This
will require careful attention to water inputs.
from the river water system because the ability
. to release water from the reservoir at
intermediate water levels is severely limited
when the reservoir.is thermally stratified.
Refill will occur during the fall and winter
using both river water inputs and natural inputs
from rainfall and groundwater. River water
inputs will be reduced or e1imin~tP1i as
necessary to ensure that dam safety
requirements are not exceeded. Until the
reservoir is reti1l~ discharges will be
minimi7.ed throughout the year to those outputs
. required to maintain acceptable flows in I~wer
Three Runs Creek (approximately 10 cubic feet
per second); only under conditions where da1ri
safety. is jeOpardized will discharges be
increased above this rate. River water inputs
may be restricted during the spring and sW11IIler
months as dictated by ecological conditions.
During heavy rainfall events in the spring and
summer, modest increases in water level are
not expected to have adverse ecological
consequences. The minimum water level to be
maintained through the spring and summer is
approximately that attained in early April.
Following this approach, it is possible, and the
intent is, that the reservoir will be refilled
during the first winter and the risk minimized.
19
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
Should that not be the case, a significant
reduction in risk associated with the -cesium-
137 contaminated sediments will still be
achieved because the most highly contaminated
of the exposed sediments will be inundated. If
only a partial refill is achieved during the fIrst
winter, a relatively short period during the
following fall should be required to complete
the refill.
The potential for remobilization of
contaminated sediments in the Par Pond
drainage during refill has been considered.
Particular emphasis has been given to the
potential for loss of contaminated sediments
from Par Pond into Lower Three Runs Creek.
The potential for significant transport from the
reservoir is considered to be low. During the
refilling operation, water will be pumped
through the river water distribution system to
the Par Pond pumphouse and released into Par
Pond. There is no reason to expect that
significant radionuclide contamination exists in
the piping system of the river water distribution
system, 50 no radionuclide resuspension is
expected to occur prior to release of this water
into Par Pond. The intake structure at the
pumphouse is configured with a concrete slab
extending the width of the intake structure and
approximately 100 it into the reservoir beyond
the headwall of the intakes (Wilde, 1985).
This concrete slab is at elevation 190 ft msl and
is therefore submerged at the, current water
level. The slab extends into the pumphouse at
the same elevation at least as' far as the pump
intakes. Consequently, water that is released
into the pumphouse flowing toward the
reservoir encounters a run of greater than 100ft
of flat concrete prior to entering the reservoir
proper. It is anticipated that prior to
encountering the contaminatPLI reservoir
sediments, most of the turbulent energy of this
water will have dissipated, thereby reducing or
eliminating its erosive potential. Should any
contaminated sediments be resuspended near
the pumphouse, the flow path from the
pumphouse to the dam is approximately 2.5
miles. It is reasonable to assume that flow
velocities are low over this flow path, and that
flow is essentially laminar (as opposed to
turbulent). Consequently, any' sediments
eroded near the pumphouse should be'
redeposited in the reservoir prior to reaching
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
the discharge pipe at the darn.
The other major source of water for the Par
Pond refIll is releases into the P Reactor canal
system. The primary releases of radionuclides
into Par Pond occurred through drainages
associated with the R Reactor drainages. These
included a natural drainage from R Area into
Pond C and the R Reactor canal svstem
through Pond B into the north arm of Par
Pond. These drainages will not be affected by
flows associated with the refill action.
Secondary contamination of the P Reactor canal
system occurred as a result of cesium-I37
mobilization by chemical cycling processes
within Par Pond and the intake of P Reactor
cooling water with low level contamination.
The last significant radionuclide introduction
into the Par Pond system occuned in 1963-64.
It is reasonable to assume that the 'majority of
resuspendable contaminated particulate matter
introduced into the P Canal system has been
flushed from the system during the subsequent
nearly 20 years of high flows through the
- system from P Reactor. Therefore, only small
amounts of.' contamin~ted . resuspendable
particles are expected to occur in the canal
system.
The entry point of the P Canal into Pond C
represents a depositional area. This could be a
point of historic radionuclide accumulation and
a potential source of resuspendable
contaminated particles. As this area has not
been evaluated for soil types or CODtamination
,levels. it should be assumed that resuspension
of contaminated particles could occur at this
area. The flow path from this area to the Hot
Dam culvert is approximately 1/3 mile and it
can assumed that this flow is non-turbulent,
thereby facilitating settling of particles.
However, the culvert from Pond C to Par Pond
pulls bottom .water from Pond C. Particles
settling to the bottom of Pond C near the
culvert can be assumed to remain in suspension
passing through the Hot Dam because of the
expected high water velocities and turbulence.
Once entering Par Pond from Pond C,
however, these particles should settle relatively
rapidly. After an initial episode of high
turbulence following exit from the Hot Dam
culvert, it can be assumed that flow velocities
are low and flow is essentially laminar. The
20
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
flow path from the Hot Dam to the cold dam
release intake is approximately 2.7 miles. It is
anticipated that, even with bottom release, most
of the particles should have settled over this
flow course.
Monitoring of the response of the dam to rises
in water level will be conducted as well as
ecological conditions in the reservoir and
monitoring of water quality of discharges from
the reservoir to Lower Three Runs Creek.
Monitoring of ecological conditions will occur
at four locations in the reservoir that have been
used in previous monitoring efforts. Water
samples will be collected in the reservoir at two .
week intervals with analyses for ammonia.
nitrate, to~ Kjeldahl nitrogen, total
phosphorus, orthophosphate, chlorophyll-a,
dissolved oxygen, and temperature. Top and
bottom samples will be collected for all
chemical analyses except as noted.
Chlorophyll-a analyses will only be conducted .
for surface' waters. Temperature and dissolved
oxygen measurements will. be conducted at
approximately 1 m intervals from the surface to
the bottom. Water samples will be qualitatively
screened to determine relative proportions of
major algal taxa. Water quality monitoring will
continue into the early fall after most, or all, of
the reservoir filling is completed.
Fish sampling will be conducted at least three
times: prior to initiation of refill, in the spring
. during the refill, and in the fall following refill.
Electrofishing will be the primary collection
technique with data analyzed to evaluate fish
community structure and recruitment. Fish
samples will be collected for mercury and
cesium-137 analyses; water and sediment
samples will also be collected at the time of fish
sampling for mercury analyses.
DOE, through an interagency agreement with
the U.S. Geologic Survey (USGS), maintains
a water level stage recorder in Par Pond and a
stream flow monitoring station immediately
downstream from Road B on Lower Three
Runs Creek. Par Pond discharges will be
. monitored at, or near, SRS Road B (see Figure
I) immediately downstream from the Par Pond
dam to test for radio nuclide releases from the
reservoir during refill.
WSRC-RP-93-1S49, REV. 0
JANUARY 26, 1995
Water quality monitoring at the Par Pond
discharge is currently conducted bi-weekly
using composite samples collected over that
period. Water samples from Lower Three
Runs Creek are analyzed for gross-alpha, non-
volatile beta, and tritium; strontium analyses are
conducted on a monthly basis. Monitoring of
water immediately downstream from the Par
Pond Dam will be modified at the time when
refill is initiated. Daily grab samples will be
collected and analyzed for total suspended
solids, gross alpha. non-volatile beta. tritium,
and cesium-137. This sampling will continue
for a period of two' weeks following the
initiation of refill. Should significantly elevated
concentrations of radionuclides be detected,.
daily monitoring will be continued for a longer
period of time. Following cessation of daily
monitoring, bi-weekly sampling will be
resumed with the same parameters as in the
cunent program (cesium-137 will be added)
being analyzed. Should the values for any of
the monitored radiological parameters approach
or exceed 50 percent of the drinking water
. standard during the refill, releases from the
reservoir will be reduced 'or' ceased until it can .
be determined that these target concentrations
will not be exceeded.
Further description of this . alten'lative appears
below. .
Treatment Components. The treatment in this
alternative would be the submergence of the
sediments with the refilling and maintenance of
the' reservoir at the 200:t 1- ft level. This
. would allow the radioactive isotopes in the
sediments to decay naturally, and would
rninimi7.e human health risks because of limited
access t() the sediments under water. The layer
of water would provide shielding which would
attenuate radiation and prevent contaminated
sediments from becoming airborne.
Engineering Controls. Controlled pumping to
and discharge from Par Pond would be
required to maintain the water level at 200 :t I
ft.
Institutional Controls. Under Alternative 2,
remaining risk would be controlled through
institutional controls. Public access to areas
within SRS is controlled by existing security
21
-------
INTERIM ACTION RECORD OF DECISION
. PAR POND UNIT
personnel and security equipment as discussed
under Alternative 1. No additional/new
controls would be instituted under this
alternative.
Ouantity of Waste. . Considering that the depth
of contamination does not exceed one foot and
the area of exposed sediments is 1340 acres,
the volume. of waste is approximately 2.2
million cubic yards.
Implementation Requirements. No implement-
ability concerns are associated with Alternative
2.
Estimated Construction and Operation and
Maintenance Costs. Implementation of this
alternative requires pumping for refilling and
maintaining the reservoir at the 2oo:t l-ft level.
Annual. pumping costs for refilling and
maintaining Par Pond at the 200:t l-ft level are
estimated to be $360,000. The. cost is an
incremental (estimated) cost (part of the total
cost) associated with the operation of the Site
Cooling Water Distribution System (river water -
system) that maintains water to Par Pond, . L
Lake, and the reactors. The river water system
will remain in service, at this time, regardless
of the action chosen for Par Pond. Therefore,
SRS would still incur the cost associated with
the operation of the pumps. The pumping cost
extended over a 3D-year period at a discount
rate of five percent would. be approximately
$5,500,000. Since the waste would remain in
place, a review of remedy would be required
every five years under SARA. Total present
worth costs for implementing this alternative,
including pumping and remedy review, are
estimated to be approximately $5,800,000 over
a 3D-year period.
MARs Associated with the Considered
Alternative. There are no chemical-specific or
action-specific ARARs associated with
Alternative 2. . Concerning location-specific
ARARs, as with Alternative 1, the Endangered
Species Act (16 USC 1531 et seq.) is
applicable to Alternative 2. Refilling Par Pond
will eliminate the additional accumulation of
contaminated sediments in deeper basin areas
caused by surface runoff on the exposed areas.
Contaminant concentrations in basin sediments
would be expected to be more evenly
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
distributed under this alternative. Accordingly,
over the long tenn, adverse effects on
endangered and threatened species would be
more similar to pre-drawdown conditions.
VIII. Summary of Comparative
Analysis of Alternatives
The NCP [40 CFR ~ 300.430 (e)(9)] sets forth
nine evaluation criteria that proVide the basis for
evaluating alternatives and selecting a remedy.
The criteria are:
overall protection of human health and the
envilonrnent .
compliance with ARARs
long-term effectiveness and permanence
reduction of toxicity, mobility, or volume
. through treatment
short-term effectiveness
implementability .
cost
state acceptance
community acceptance
Overall Protection of Human Health. and the
Environment. Alternative I would not achieve
any reduction in human health risks posed by
the dra~down of Par Pond. Alternative 2
would provide a reduction in carcinogenic risk
due to the shielding provided by the overlying
surface water after refilling of the pond. In
addition, Alternative 2 would e1;minate direct
exposure to the contaminated sediments.
.
.
.
.
.
.
..
.
.
Under Altem~ve 1, the ecosystem alteration
and instability resulting from Par Pond
drawdown would continue as the ecosystem.
adjusts to drawdown conditions. Alternative 1
would result in continued exposure .to
cont3II1inated sediments and would
permanently eliminate approximately 1340
acres of wetland and aquatic habitat present
prior to draw down of the reservoir.
Implementation of Alternative 2 would result in
eventual re-establishment of the aquatic habitat
and wetlands to essentially pre-drawdown
conditions.
Compliance with Applicable or Relevant and
Appropriate Requirements (ARARs). No
chemical-specific or action-specific ARARs are
associated with either Alternatives I or 2. The
22
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
Endangered Species Act is the location-specific
ARAR associated with the alternatives.
Alternative I allows for the potential of
. increased adverse effects to endangered and
threatened species through increased potential
for sediment loading to the reservoir and
subsequent uptake of accumulation in prey
species. With implementation of Alternative 2,
Par Pond will more closely resemble conditions
for these endangered and threatened species
that existed before drawdown.
Long-Term Effectiveness and Permanence.
The magnitude of risk associated with
Alternative I will decrease over time due to the
natural decay of cesium-137. The ecosystem
would eventually adjust to conditions of the
181-ft drawdown water level; however, the
habitat on the majority of the 1340 acres of
. exposed sediments would be. pennanently
altered to a texrestrial structure.
The magnitude of risks under Alternative 2 will
essentially remain unchanged for the time
required for dam. repair. and water level
restoration. Upon completion of restoration of
the water level under Alternative 2, risk due to
direct exposure and inhalation of contmrinated
sedim,ents would be minimi7ed. The eco-
system would recover to essentially pre-
drawdown conditions (wetlands and aquatic
habitat) under Alternative 2, as compared to
Alternative 1, maintaining the water level at the
181-ft level.
Reduction of Toxicity. Mobility. or Volume.
Alternative 1 would not reduce the mobility of
waste constituents. Contaminant uptake by
mobile texrestrial animal species could result in
migration of contamination away from Par
Pond. The toxicity (in terms of radioactivity)
and volume of cesium-137 would decrease
over time by the natural radioactive decay
process. Cesium-I37 has a half-life of 30
years. Accordingly, the activity has decreased
to approximately one-half the original
concentration resulting from the process
releases that occurred in the 1950s and 1960s.
The activity will continue to decrease at this
rate.
Alternative 2 would minimize the airborne
mobility of the contaminated sediments. In
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
addition, offsite migration through terrestrial
animal movements would be precluded.
However, contaminant mobility through
migration of waterfowl and predator animal
species feeding on contaminated flora and
animal prey could continue with both
alternatives. As with Alternative 1, the toxicity
and volume of cesium-137 would be reduced
through radioactive decay. Gamma attenuation
would occur through restoration of the water
level.
Short-Tenn Effectiveness. Alternative 2 can be
implementedirnmediately without increased
risk to the community or workers. The
alternative itself poses no adverse
environmental impacts. In comparison to
Alternative 2, Alternative 1 will not reduce
risks from exposure to Par Pond sediments or
provide lessening of environmental impacts for
the effects of drawdown.
Implementability. Alternative 1 is readily
implementable. Refill under Alternative 2 may
. need to be conducted in stages over time to
prevent rapid sediment resuspension and
decreases in dissolved oxygen content of the
water column.
Cost. Repair of the dam was completed on
July 1, 1994, conducted under the auspices of
the Atomic Energy Act (ABA), and is not
included in the evaluation of costs for the
alternatives. Alternative 1 requires no additional
remediation cost; however, maintenance costs
include pumping. costs (approximately
$280.000 annually) to maintain Par Pond at the
181-ft level and a remedy review every five
years (esrim~tP.d at $280.000 over a 3D-year
period) for a total present worth cost of
approximately $4,600.000 over a 3D-year
period. Alternative 2 requires costs for
pumping to maintain the water level at 200 :t I
ft (estimated at $360.000 annually) and
remedy review every five years for a total
present worth cost of $5,800,000 over a 30-
year period.
State Acceptance.
South Carolina as well as EP A have accepted
the preferred alternative for the proposed interim
. action.
23
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
ComrnunitV Acceptance.
Comments from the public have been
incorporated in the IROD. Please see Section
XI, Explanation of Significant Changes, and the
Responsiveness Summary for details.
IX.
Selected Remedy
Alternative 2 is the preferred interim action
alternative. Alternative 2 consists of restoring
and maintaining the water level in Par Pond to
the 200:t l-ft level following repair of the Par
Pond Dam. As a result, exposed sediments
would be submerged under a layer of water.
The water layer would provide a reduction in
risk due to attenuation of radiation and would
preclude contaminated sediments from
becoming airborne. The ecosystem of Par Pond
would eventually recover to essentially pre-
draw down conditions following implementation
of Alternative 2.
Within 15 days of the signing (approval) of the .
IROD, SRS will submit an outline for the post-
IROD documents; the Remedial Design!
Corrective Measures Design and Remedial
Action/Corrective Measures implementation
Plans. The post-IROD documents will be
submitted within 30 days after the outline is
approved by EPA and SCDHEC. The interim
remedial action will begin after the post-IROD
documents are approved.
X. Statutory Determination
This interim action remedy is protective of
human health and the environment, complies
with Federal and state applicable or relevant
and appropriate requirements directly
associated with this action, and is cost-
effective. This interim remedial action utilizes
permanent solutions and alternative treatment
(or resource recovery) technologies, to the
maximum extent practicable, given the limited
scope of the action. Because this interim
remedial action does not constitute the fmal
remedy for the Par Pond unit, the statutory
preference for remedies that employ treatment
that reduces toxicity, mobility, or volume as a
principle element will be addressed by the final
response action. Subsequent actions are
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
planned to fully address the principal threats
posed by the Par Pond ,unit.
Since this is an IROD, review of this unit and
of this remedy will be ongoing through
implementation of the Remedial Investigation
and Feasibility Study process required in
accordance with the terms of the FF A as DOE,
the EP A, and SCDHEC continue to develop
fmal remedial alternatives for the Par Pond
unit.
Explanation of Significant
Changes
Comments received during the public comment
period suggested that SRS should not maintain
the pond at full pool but let it fluctUate
naturally. The reasons expressed for this
option were cost and the incompleteness of the
. data available to determine the acruallpotential
risk of the waste unit.
XI.
Based on the impact from the public and
discussions with the regulatory agencies, the
preferred alternative (Alternative 2) outlined' in
the IAPP is being modified by this IROD to
include refill and maintenance of the pond at
200 ft msl:t 1 ft until a National Environmental
Policy Act (NEP A) evaluation of this
modification alternative can be evaluated. Once
the NEP A documentation is completed and
assuming the proposed action is acceptable,
SRS will allow the pond to fluctuate naturally
until the final CERCLA action is complete.
OOE is required through NEP A regulation (10
CFR PART 1021) and OOE Order 5440.lE to
assess the environmental impacts of any
proposed action which may potentially have
significant effects on the environment. DOE is
committed through the regulation to follow the
letter and spirit of NEP A, fully comply with the
Council on Environmental Quality (CEQ)
requirements, and apply NEP A early in the
planning phases of a proposed action, such as
the evaluation of the potential impacts of
fluctuating water levels on Par Pond. CEQ
required DOE to prepare a Special
Environmental Analysis to assess the impacts
of the draw down, repair, and refill back to the
200 ft. level. Additional NEP A documentation
will be required to' evaluate the potential
24
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
environmental impacts associated with the
fluctuation of the water level from full pool.
Appropriate NEP A documentation will be
prepared to evaluate the potential environmental
impacts, and any associated mitigation
measures, of allowing Par Pond's water level
to fluctuate naturally. This proposed action
would include the discontinuation of pumping
from the Savannah River once the Pond has
been refilled to the 200 ft. (:t 1 ft) level. The .
NEP A documentation will focus on the
potential impacts of reduced and/or fluctuating
water levels on the ecology, potential impacts
on the ecosystem from reduction of nutrients as
a. result of discontinuing pumping from the
Savannah River, and assessment of the Pond's
water level - in balance with maintaining
minimum flow in Lower Three Runs Creek. It
is estimated that the NEP A evaluation will be
completed in 1996 or 1997.
Based on recent studies and modeling
conducted by various internal and external
org;mi7~tions, PAR Pond will fluctuate
naturally between 190 to 200 ft. ms!. This
means that at different times, between 0 and
800 acres of contaminated sediment will be
above the water line. The pond will loose the
nutrients that have been provided from the
Savannah River water for the past 33 years.
While most natural lakes and ponds maintain a
fairly constant level, except in extreme
conditions, the equilibrium point of PAR Pond
is unknown and the level will probably
fluctuate more than a natural lake since the
pond is man-made. Personnel access to PAR
Pond sediments will remain restricted.
XII.
References
Bechtel, 1991. Par Pond Dam Seepage
Investigation, Recommended Repair
Options, Prepared for Bechtel Savannah
River, Incorporated by Bechtel
Geotechnical Services, December 1991.
Chen, K.F., 1994. Response to Item #8 of
us EPA Technical Review Comments for
Par Pond Interim Proposed Plan, Savannah
River Superfund Sire. Aiken. Sc.
Memorandum to 1. Gbdden, SRT-ETS-
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
941219. Westinghouse Savannah River
Company, Savannah River Site, Aiken,
South Carolina.
COE (U.S. Anny Corps of Engineers), 1987.
Wetland Delineation Manual, Subsection
VI, Man-Induced Wetlands.
DOE (U.S. Department of Energy), 1994.
Public Involvement, A Plan for the
Savannah River Site. Savannah River
Operations Office, Aiken, South Carolina.
DOE (U.S. Department of Energy), 1992.
Special Environmental Analysis for PaT
Pond at the Savannah River Site. Savannah
River Field Office, Aiken, South Carolina.
DOE (U.S. Department of Energy), 1993.
'Supplement Two to Par Pond Specio.l
Environmental Analysis, Observed
Environmental Impacts (Draft). Savannah
River Operations Office, Savannah River
Site, Aiken, South Carolina.
. Du Pont (E.!. du Pont de Nemours &-
Company), 1987. Comprehensive Cooling
Water Study, Final Report, Volume III,
Radionuclide and Heavy Metal Transport.
DP-1739-3. Savannah River Laboratory,
Aiken, South Carolina.
EPA (U.S. Environmental Protection Agency),
1988. Guidance for Conducting Remedial
Investigations and F easihility Studies unLkr
CERCLA, Interim Final, EP AJ540/ G-
89/004, Cincinnati, Ohio.
EPA (U.S. Environmental Protection Agency),
1991a. Role .of Baseline Risk Assessment
in Superfund Remedy Selection Decisions.
Office of Solid Waste and Emergency
Response - OSWER Directive 9355.0-30.
EPA (U.S. Environmental Protection Agency),
1991b. Risk Assessment Guidance for
Superfund: Volume I - Human Health
Evaluation Manual (Part B, Development of
Risk-based Preliminary Remediation
Goals). Office of Emergency and Remedial
Response. Pub!. 9285.7-01B.
25
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
EPA (U.S. Environmental Protection Agency),
1991c. Human Health Evaluation ManuLll,
Supplemental Guidance: Standard Default
Exposure Factors, OSWER Directive
9285.6-03, Environmental Protection
Agency, Washington, D.C.
FFA, 1993. Federal Facility Agreementfor the
Savannah River Site, Administrative
Docket Number 89-05-FF (effective date:
August 16, 1993).
Fleddennan, P., 1991. Special Sampling in
Response to Par Pond Drawdown.
Memorandum ESH-EMS-910119.' West-
inghouse Savannah River Company,
Aiken, South Carolina.
Hamby, D.M., 1991. Offsite Cesium
Concentration (Par Pond). Westinghouse
Savannah River Company. Interoffice
Memorandum to L.B. Smith, September I,
1992.
Lindsay, W.C., 1979. Chemical Equilibria in .
Soils, Colorado State University, Fort
Collins, Colorado.
. Marter, W.L. and W.H. Carlton, 1991.
Preliminary Assessment of Radiological
Impact of Par Pond Dam Repair. SRL-
ETS-910379, August 14, 1991.
Mayer, J.J., R.T. Hoppe, and R.A.
Kennamer, 1985. Bald and Golden Eagles
on the Savannah. River Plant, South
Carolina. The Oriole, 50(4):53-57.
Mayer, J.J., R.T. Hoppe, and R.A.
Kennamer, 1986. Bald and Golden Eagles
of the SRP. Savannah River Ecology
Laboratory Report, SREL-21, UC-66e,
Savannah River Ecology Laboratory,
Aiken, South Carolina.
Pekkala, R.O., C.E. Jewell, W.G. Holmes,
and 1. W. Marine, 1987. Environmental
Information Document for the ReactOr
Seepage Basins. DPST-85-707. E. 1. du
Pont de Nemours & Co., Inc., Aiken,
South Carolina.
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
Whicker, F.W., 1991. Radiological Impli-
cations 0/ the Par Pond Drawdown, In
1991 Summary Report of Par Pond
Research. C. Ercolano [ed.), Savannah
River Ecology Laboratory.
Whicker, F.W., 1992a. Aquatic and
Ten-estrial Vegetation Survey of Par Pond
and Garden Plot Study: Preliminary
Information. Savannah River Ecology
Laboratory, Aiken, South Carolina.
Whicker, F.W., 1992b. Response to Your
Request to Think About the Consequences
of Leaving Par Pond oJ 181 Feet
Indefinitely. Memorandum to A. Doswell.
Savannah River Ecology Laboratory,
Aiken, South Carolina.
Whicker, F.W.,. D.J. Niquette, and T.G.
Hinton, 1993. To Remediilte or Not: A
Case History. Proc. 26th Midyear Topical
Meeting of the Health Physic Society,
Coeur d'Alene, Idaho.
Wilde, E.W. and Tilly, L.J., 1985. Influence
of P-Reacror Operation on the Aquatic
Ecology of Par Pond: A Literature Review,
DP-1698, E.1. du Pont de Nemours and
Company, Inc., Savannah River Plant,
Aiken, South Carolina.
Wilde, E.W., 1985. Compliance of the
Savannah River Plant P-ReactOr Cooling
System with Environmental Regulations,
DP-1708, E.I. du .Pont de Nemours and
Company, Inc., Savannah River Plant,
Aiken, South Carolina.
Wilde, E.W., [ed.) , 1987. Ecology of Par
Pbnd, Comprehensive Cooling Warer
Study, Volume VII, DP-1739-7, E.I. du
Pont de Nemours and Company, Inc.,
Savannah River Plant, Aiken, South
Carolina.
Winn, W.G., 1993. Measurements of
RadionucliO.es in Par Pond Sediments with
an Underwater HPGE DetectOr (U).
WSRC-TR-93-0209. Westinghouse
Savannah River Company, Aiken, South
Carolina.
26
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
WSRC (Westinghouse Savannah River
Company), 1991a. Savannah River Site
Environmental Report, 1990. WSRC-IM-
91- 28, Aiken, South Carolina.
WSRC (Westinghouse' Savannah River
Company), 1991. Par Pond Dam (U), letter
from D.E. Gordon (Manager,
Environmental Restoration and Ground-
water Section, Environmental Protection
Department, Westinghouse Savannah River
Company, Aiken, South Carolina) to James
H. Scarbrough (Chief, RCRA and Federal
Facilities Branch, U. S. Environmental
Protection Agency - Region IV, Atlanta,
Georgia), July 17, 1991, ESij-ERG,.
910599.
WSRC (Westinghouse Savannah River
Company), 1992. Baseline Risk
Assessment Using Existing Data for Par
Pond, WSRC-RP-91-1197, Revision 1,
prepared for Westinghouse Savannah River
Company by Oak Ridge National
Laboratory, M~ Marietta Energy
Systems; Inc., Oak Ridge, Tennessee.
WSRC (Westinghouse Savannah River
Company), 1993. SRS Ecology
Environmental Information Document.
WSRC-TR-93-496. Savannah River Site,
Aiken, South Carolina.
WSRC (Westinghouse Savannah River
Company), 1994. Interim Action Proposed
Planfor the Par Pond Unit. WSRC-RP-92-
1170, . Rev.l. Savannah River Site, Aiken,
South Carolina.
27
-------
INTERIM ACTION RECORD OF DECISION
PAR POND UNIT
APPENDIX A
WSRC-RP-93-1549, REV. 0
JANUARY 26, 1995
RESPONSIVENESS SUMMARY.
-------
Responsiveness Summary
During the public comment period for the proposed interim action for the PAR Pond operable uni t,
a public information meeting was held to discuss the proposed action with interested members of
the public. The meeting was held on December 14, 1995 in Aiken South Carolina. Approximately
35 people attended the meeting (including the SRS and regulatory agency personnel).
The public meeting was divided into three main segments: 1) a general introduction section, 2) a
discussion about the proposed PAR Pond in~erim action and 3) a question and answer session. A
transcript of the meeting is available in the Administrative Record File for the PAR Pond unit.
During the public comment period, several letters were submitted from individuals and groups
regarding the proposed iI1terim action. Questions raised during the discussion included general
information questions regarding the physical state of the unit, how SRS was planning to refill the
pond,. dam safety issues, the accuracy of the costs and the method of determining the cost estimate,
impacts (potential risks) to workers, residents and wildlife. This Responsiveness Summary
addresses the general comments and concerns from the public meeting and specifically addresses
the written comments received. The summary is divided into two sections: 1) general responses
and discussions to significant issues raised during the meeting, including modification of the
proposed action, and 2) specific responses to the written comments received. Please note, some
of the specific comments will be addressed by the general response section due to common
questions and concerns. Also, some comments. were received about the meeting format. These
comments will be taken under consideration for future public meetings.
General Responses:
. Modification to the preferred alternative: Alternative #2 - Refill and maintain PAR Pond at 200
ft (:tl ft) msl.
Some comments received suggested that SRS should not maintain the pond at full pool but let it
fluctuate naturally. The reasons expressed for this option were cost and the incompleteness of the.
data available to determine the actua]fpotential risk of the waste unit One written comment and one
voiced at the meeting recommended SRS implement the no action alternative, i.e. maintain the
pond at the 181 ft. ms!. The written comment expressed a plajor concern regarding Ule cost to
maintain the pond and the voiced comment focused on a concern for dam safety.
The preferred alternative (alternative 2) in the IAPP will be modified to state that
SRS will refill and maintain the pond at 200 ft IDSI :t 1 ft until a National
Environmental Policy Act (NEP A) evaluation of a reduced flow to Lower Three
Runs creek (the creek below PAR Pond Dam), fluctuating pond water level and the
ecological impacts of not continuing to provide river water, through pumping, to
PAR Pond can be evaluated. If the NEP A evaluation indicates that a fluctuating
water level is acceptable, the appropriate post-ROD CERCLA documentation will
be prepared to support the decision. .
DOE is required through the National Environmental Policy Act regulation (10 CFR
PART 1021) and DOE Order 5440. IE to assess the environmental impacts of any
proposed action which may potentially have significant effects on the environment.
DOE is committed through the regulation.to follow the letter and spirit of NEP A,
fully comply with CEQ regulations, and apply NEP A early in the planning phases
of a proposed action, such as the evaluation of the potential impacts of fluctuating
water levels on Par Pond. CEQ required DOE to prepare a Special Environmental
RS-I
-------
Analysis to assess the impcts of the drawdown, repair, and refill back to the 200
ft. leveL Additional NEP.-\ documentation will be required to evaluate the potential
environmental impacts associated with the fluctuation of the water level from full .
pooL
Appropriate NEP A documentation must be prepared to evaluate the potential
environmental impacts, and any associated mitigation measures. of allowing Par
Pond's water level to fluctuate naturally. This proposed action would be the
discontinuation of pumping from the Savannah River once the Pond has been
refilled to the 200 ft. (:t 1 ft) level. The NEP A documentation will focus on the
potential impacts of reduced and/or fluctuating water levels on the ecology, potential
impacts on the ecosystem from reduction of nutrients as a result of discontinuing
pumping from the Savannah River, and assessment of the Pond's water level in
balance with maintaining minimum flow in Lower Three Runs Creek.
Orice the NEP A documentation is completed and assuming the proposed action is
acceptable. SRS will allow the pond to fluctuate naturally until the fmal CERCLA
action is complete. The appropriate CERCLA documentation will be prepared prior
to allowing the pond to fluctuate. It is estimated that the NEP A evaluation will be
completed in 1996 or 1997.
Based on recent studies and modeling conducted by various internal and external
organizations, PAR Pond water level will fluctuate naturally between 190 to 200 ft.
rnsl. This means that at different times. between 0 and 800 acres of contaminated
. sediment will be above the water line. The pond will loose the nutrients that have'
been provided from the Savannah River water for the past 33 years. While most
natural lakes and ponds maintain a fairly constant level, except in extreme
conditions, the equilibrium point of PAR Pond is unknown and the level will
probably fluctuate more than a natural lake since the pond is man-made.
Personnel access to PAR Pond sediments will remain restricted.
.
Cost Estimate
The costs provided in the IAPP and IROD are for performing the remedial actions -
refilling and maintaining the pond and the 5 year remedy reviews. The cost
includes the estiT}1::1ted annual pumping costs and o&M costs associated with the
operation of the pumps. The cost is an incremental (estimated) cost (part of the
total cost) associated with the operation of the Site Cooling Water Distribution
System (river water system) that maintains water to PAR Pond. L Lake and the
reactors. The river water system will remain in service, at this time, iITegardless of
the action chosen for PAR Pond. Therefore SRS would still incur the cost
associated with the operation of the pumps. The remedial costs presented were
. addressed per EP A guidance. The Superfund program recommends that the present
worth be calculated at a 5% discount rate (interest) before taxes and after inflation
be assumed (discount rate applied prior to taxes and after inflation). The thirty year
time frame is the maximum allowable per the regulations, thus resulting in the
maximum cost estimate (OSWER 9355.3-01 pg. 6-12). It is used for estimating an
comparison purposes only. A time frame of ten years could have been used. It
does not mean that SRS plans to maintain this interim action for thirty years.
Present worth analysis is used to evaluate expenditures that occur over d~fferent time
periods by discounting all future costs to a common base year. usually the year in
\vhich the estimate is prepared. This allows the cost of remedial action alternatives
RS-2
-------
to be compared on the basis of a single figure representing the amount of money
that, if invested in the base year and distributed as needed, would be sufficient to
cover all costs associated with the remedial alternative. In other words, in every
investment, it needs to be recognized that a dollar invested today is worth more than
a dollar tomorrow because of the interest cost which is related to all expenditures
which occur over time. Dollar benefits which accrue in the future cannot be
compared directly with investments made in the present because of the time value of
money. Discounting is a technique for converting various cash flows occurring over
time to equivalent amounts at a common point in time. It is recommended by the
Office of Management and Budget (OMB) that costs in future years should not be
escalated to account for general price inflation, except where there is a reasonable.
basis for predicting differences in the relative escalation of costs ( or benefits)
associated with the project (i.e. if the operating costs will be increasing). Otherwise,
the estimation should use constant (base period) dollars. OMB recommends a
discount rate of 10%, which represents "the average rate of return on private'
investments, before taxes arid after inflation" (OMB, circular A-94). In other
words, inflation is accounted for in the discount rate:
[ (1 + i)" - 1 ]
P=A
i(1 + i)"
P - present worth
A - annual payment/yearly disbursement
. i-interest rate/discount rate
The present worth of the preferred alternative is approximately $5.5 MM. This is
the present worth of $360,000 for 30 years using a present worth factor (discount
rate/interest rate) of 5%. The total present worth cost also includes the 5 year
remedy reviews as require~ by the regulations. Present worth can be viewed as the
amount of money that will be needed now in order to fund a future outlay(s). In this
case a unifonn series of$360Klyr. The 5% discount rate does not mean that the
cost is reduced by 5% each year, it is actually increased 5% a year. Specifically,
$360K in the first year is equal to $378K the second year. Using the present worth
discount rate allows a comparison/evaluation the total lifetime cost(s) in present
dollar value. The futUre value (value spent at the end of the lifetime in future dollars)
is not $1O.8MM ($369K x 30 yrs) but rather $23MM. .
Maintaining the pond at the 181 foot level also has an annual O&M cost associated
with it. In order to maintain the pond at 181 ft. discharging of water from the pond
is required. Also, at times some pumping (and discharging) is required to maintain
flow to Lower Three Runs. The river water system is being maintained to pump and
discharee water from PAR Pond to maintain the lower water level and also to
provide"" water to L Lake and other systems that use the water. It was estimated from
the operating department, that it takes a slightly less level of effort to maintain the
pond at 181 ft. than at full pool. The cost to maintain the pond at the 181 foot level
was estimated to be $280,OOO/yr.
The annual $360Klyr. O&M cost to maintain the pond at full pool is the best
estimate available from the operating department. This is what has been budgeted.
This figure may vary annually depending upon pump usage. During the initial refill,
the cost could be as high as $500K to $700K, depending upon pump usage (average
pumping rate versus maximum pumping). natural inputs. maintenance problems etc.
RS-3
-------
By the same token, the annual cost could be lower if it is a wet year. This annual
cost is part of the nonna! annual operating budget for river water system. If this
CERCLA action had not occurred (i.e. drawdown and refill), these moneys would
be spent maintaining the pond regardless.
This analysis can also be used to support the proposed change to the preferred
alternative. The best way to minimize the costs would be to eliminate pumping
and/or siphoning. In other words, letting the pond fluctuate naturally. No true cost
saving, though, would be realize4 until the Site Cooling Water Distribution System
(river water system) is completely shur down.
. Verbal comment from the meeting: Mr. David Christianson - "...it appears to be that we drew
down the water to its current level in order to repair the dam, that its present low level is more of a
stable condition than full pool. And, in that case, it would appear to me that the cheapest, most
cost ~ffective scenario to maintain the PAR Pond at that depressed level. while we are doing other
studies to determine its configuration. And that is - that's all I really wanted to say, that it appears
to me that it's a stable configuration right now, more stable than if it were full, and I believe that
we should. maintain it at that until we determine its ultimate destination. "
Response:"
The design for the repair of the uncontrolled seepage problem at PAR Pond Dam
was reviewed by the US Anny Corps of Engineers, the Bureau of Reclamation, and
the Federal Energy Regulatory Commission (FERC). All parties agreed that the
designed repair would return the dam to a safe condition. The repair was completed
to the specifications in the design documents. The FERC conducted periodic"
inspections during the construction phase of the repair. These inspections reported
that the observed work appeared to be in" accordance with approved plans and
specifications. Their final inspection will be performed after the reservoir is returned
to full pool (El. 220 ft.).
Since the repair of the dam is not part of this CERCLA action, details of the dam
repair will not be added to the IAPP or IROD. For the purposes of this proposed
action. the dam will be in a safe condition for refilling the pond. This is stated in the
IAPP and IROD.
RS-4
-------
Written Comments Received on the Par Pond fnterim Action Proposed Plan
Taxpayers for Responsible Infrastructure Management (TRIM)
Jackson, South Carolina
"TRIM is a grassroots organization devoted to th£ effective management of our federal lands and
resources. We believe that risk numagement should be utilized to focus the scarce funding for
environmental restoration where it will contribute the most to the environment. We choose to
participate in this process via written comments. We feel that our method of participation preserves
the working relationships of our members with DOE, Federal and State regulators, and tfreir
contractors.
We have read the available ma1erial related to Par Pond, and attended tfre meeting on December
14th in Aiken. There are many issues that we feel compelled to comment on, and these OTe
captured in Attachment 1. .
We would like to propose and additional alternative, herein referred to as "Alternative 3", to be
considered: fill the pond, and let the level vary with raUifall just like a natural lake. Attachment 2
is a draft of proposed Alternative 3. We believe Alternative 3 is safe, protective of both man and
beast, and is far more cost effective based upon the following logic:
.
The exposed sediments contain 9 curies Cesium, which is by far the worst hazard to human
or creature. The exposure to workers during the period the pond was drawn down was so
small, the radiation monitoring was not required A IUrear correlation of exposure v s.
exposed sediments is conservative, based upon the stated fact that th£ worst areas of
contamination are in the deeper sections of th£ pond. This is somewhat offset, however,
by the fact that exposure of sediments is th£ greatest with the first few feet of level decrease
due to the slope of the shoreline. On balance, it appears that the risk in Alternative 3 would
be an order of magnitude less thaJ with alternative 1 (pond at 181 '), and very dose in
magnitude that of Alternative 2.
.
No evidence of hann to wildlife from uptake of Cesium or mercury was observed with the
pond at 181'. The vegetation uptake is proportional to the quantity of folio.ge growing in
tfre contaminated sediments; with Alternative 3, the amount of foliage growing in the
contaminated sediments will be essentially equal to that of Alterru;ztive 2; the foliage will not
be able to establish itself in an area of varying water level.
.
The uptake of contaminants is also proportional to the area of habitat established on
exposed sediments on which the nonvegetative food chain exists. The area of habitat
established on exposed sediments tI17Ikr Alternative 3 is, if anything, less than that of
Alternative 2.
Therefore Alternative 3 presents no substantial difference in risk than Alternative 2. It also satisfies
all the expressed concerns of the regulators and tfre public (excepting the earth£n dam concern).
and is far more cost effective. .
Should EPA disagree with the merits of our proposal, we would urge you to consider this proposal
from a risk management perspective; we find that the exposed sediments at Par Pond present
insufficient risk to warrant the expenditures proposed. The sediments were exposed for the last
three years, without evidence of hann.; surely what is prudent is to let the pond level vary with
rainfall until more data is collected, if EPA indeedfeels that this is indeed warranted.
RS-S
-------
In the event that the EPAfeels that there is insufficient data to justify the exposure due to'varying
water level. perhaps the interim action should include a provision that once further assessment of
risk is complete. the pond will be allowed to vary. This would elimino.te the need to develop
another interim plan (the cost of which never appears in any discussion of alternatives).
We encourage you to give this proposal consideration as the preferred alternative.
We would like to request the comment transcript or SummJ1ry from the December 14 public
meeting, and copies of all written stakeholder comments as well. Thank you for inviting us to
participate in this process, and please keep us on the distribution for future correspondence. We
look forward to your response. " ,
Response to TRIM Letter:
. Based on public input on the proposed action for PAR Pond, the preferred
'alternative will be modified to state that the pond will be refilled and following a
required NEPA evaluation, the pond will be allowed to fluctuate assuming the
NEP A evaluation supports this action. See the fIrst general response. Note that a
new alternative, alternative 3 as proposed, is not needed to implement the change.
The existing preferred action can be modified without developing a new alternative
within the current CERCLA documentation.
SRS believes TRIM's letter was well presented and thought out. However, there
are some slight inaccuracies that need to be clarified. Although the statement that
the risk to workers. during the drawdown was negligible is correct, the risk
evaluation based on existing data indicated, based on a modified standard worker
scenario, that personnel working on the sediments could be at risk due to exposure.
The standard default EP A values for risk assessments, which are conservative,
were modified to reflect actual site working conditions. Currently worker access to
the sediments is controlled and monitored and minimized. It is correct, as stated in
the meeting, that workers are not required to wear radiation monitors. However,
this is not because that the potential risk, as calculated, is low, but because the
exposed sediments do not meet the definition of a radiological
controlled/contaminated area. There are specific guidelines specified by DOE as to
, when monitoring inside a contaminated area is needed. These are different than
,risks'calculated under CERCLA. . '
The existing estimate of worker risk is based on limited data. In order to gain an
accurate estimate, more data would be required. A new evaluation may indicate
there is a different risk that originally estimated. Based on the infonnation
available, the DOE, EP A and SCDHEC are being protective of human health and
the environment by being conservative and recommending the refilling and
maintaining of the pond, to reduce the potential risk, until more infonnation
becomes available.
Although there is no evidence of harm to wildlife from uptake of CS-137 or
mercury there has been a noticeable increase in the uptake of cesium in some of the
animals and vegetation on the sediments. The uptake levels have not yet reached a
dose level where harm to wildlife will occur. The longer wildlife is exposed or can
be exposed to the sediments the greater the uptake of contaminants will be and the
greater the risk of physiological harm becomes. Wildlife monitoring will continue.
Also, some of the nutrients supplied from the river water displace the uptake of CS-
! 37 and mercury in plam and animals. Potassium is on~ of these nutrients.
RS-6
-------
Therefore, by adding river water to the pond, SRS is reducing the possibility that
the uptake levels may reach an unacceptable level.
1340 acres of aquatic habitat was lost (loss of the entire littoral zone) during the
drawdown. The impacts from the drawdown are cUITently more visible than those
associated with the contaminants in the sediments. Effects of the drawdown were
outlined in the IAPP.
All comments received, as well as the meeting record will be placed in the
Administrative Record File for the PAR Pond waste unit. If possible, copies will
be sent to TRIM.
TRIM Comments on the Par Pond Interim Action Proposed Plan
"1. The agencies involved do not fulfill the need for public participation in this process, because
. the are still in the Decide-Announce-Defend mode ra1her than seeking a Win- Win solution. Some
regulators hide behind regulations, and when defending the proposal indicate that 'the regulations
require such and such'. No one argues the need to comply with our laws and regulations. In
many cases the laws and regulations require issues .to be addressed, but do not specify how they
are addressed. Thus when the public comments, the responders should ask themselves, "how can
I accommodate this stake holder within the constraints of the regulations?" rather than explaining
how the regulation constrains them.
The best example of this was the discussion of alternatives. The regulators limit discussion to the
alternatives being proposed, while other alternatives may be available that address the stak£ holder
issues and comply with the regulations. The agencies do not solicit solutions from stake holders
we never hear "how could we accommodate this concern within the constraints of the regulations?"
The alternative that we present in this memo could have easily come to light with proper
facilitation.
From the information presented, three concerns were identified by EPA, DOE, and the Public; J) .
risk to human health; 2) risk to the environment; 3) cost effectiveness. The following comments
address each of these concerns. "
Response:
Additional alternatives proposed by the public are always considered. However, the
IAPP only proposed 2 actions and that is what was presented to the public. Under
the RCRNCERCLA process, upon receipt of public comments, the alternatives are
reviewed to detennine if the option chosen is still the preferred alternative. DOE has
discussed the Par Pond IAPP with some stakeholders on numerous occasions. The
Natural Resource Trustees were given two or three briefmgs on the proposed
. alternatives. Several briefings were given to. EPA and SCDHEC at quarterly
meetings. A public meeting was held in Aiken where Par Pond was discussed in
great detail, prior to the development of the IAPP. .
As a result of the Public meeting held on 12/14/94 and comments received at that
meeting, DOE is proposing to refill and maintain the reservoir until the NEP A
process has been complete. NEP A will consider the ecological and other possible
impacts of allowing the PAR Pond water level to fluctuate naturally. Should this
alternative have acceptable environmental impacts it will be pursued. Therefore in
this case, public participation helped DOE and EP A concur with the selection of the
alternative proposed in the TRIM letter.
RS-7
-------
"Human Health Risk
2. The documentation clearly states than the situation at PAR Pond does not present a risk to the.
general public. Therefore, the IAPP does not need to address this topic. The risk to a hypothetical
resident is reportedly greater, so the regulation requires that this be addressed. Given the fact thaI
this is an interim action, and that residence of PAR Pond is not a reality in the near future, the
IAPP should simply conclude that prior to establishing anything greater than worker exposure to
PAR Pond, that an appropriate analysis be conducted a1 that time. Anything further would be a
great waste of taxpayer dollars."
Response:
SRS agrees with the comment. Since this is an interim action and not a final action,
the IAPP did focus on the "immediate problem and not the potential of a future
resident. The first revision (version) of the IAPP did present alternatives that
focused on more permanent solutions to the problem, but was modified based on
EI>A comments similar to TRIM's. The risk assessment, based on limited existing
data, did evaluate the future resident scenario as required by CERCLA guidance,
however, for the purposes of the IAPP an attempt was made to focus on the
current potential risks. The fmal CERCLA action will focus on the hypothetical
future resident, depending upon future land use decisions, as well as the other
required scenarios.
"3. . The risk to the worker was'identijiedas 'moderate', with a numerical value assigned of 10-4
to 10-6 chances of an additional cQ1lCer per year. The calculation that arrived a1 this figure was
undoubtedly very conservative, due to the lack of hard and fast data. The risk identified was due
to the radiation in the sediments exposed in the drawdown. It was also pointed out, however, thaI
radiation monitoring is only required for workers if the dose exceeds 100 millirem (per year?). If
this is the worst risk to human health, one can only conclude that the' risk.to workers is negligible,
since it is clearly less risk than that of many site workers who do have to wear radiation
monitoring. We feel that sufficient da1a. is available to support the position that with the pond CJ1
any water level >181' there is no appreciable risk to the workers."
Response:
The guidelines that determine when radiation monitoring is required are different
than these that are used to calculate and estimated risk under CERCLA. DOE and
the NRC regulate when radiation monitoring is needed. Radiation monitoring, as
well as designating' an area "Radiologically, Controlled or Contaminated", is
determined by internal procedures that follow DOE guidelines. Although PAR
Pond workers are not required to wear radiation monitors; this does not mean that
there is no risk to the workers present. It means that it does not meet the defmition
of a radiologically controlled area. The risks determined by CERCLA are based on
a different set of conditions. As stated previously, .the default conservative EPA
parameters were modified for the worker scenario to reflect actual site conditions.
If the standard conservative EPA parameters were used, the risk would probably
have been estimated in the area of 10-2 excess cancers per year.
The radiation limit for formally trained radiation workers at the Savannah River Site
is currently 3000 rnrem per year. The radiation limit for members of the general
public is 100 mremlyear and it is that .limit that is applicable to workers on the Par
RS-8
-------
Pond CERCLA unit. Three independent estimations of the radiation dose received
by full-time workers at Par Pond (8 hr/day for 250 days per year) showed that the
potential dose rate is in the range of 16 to- 22 rnrem/yr. Consequently, personal.
monitoring devices are not required by workers on Par Pond, but are available if
requested. No special protective clothing is required for entry to the Par Pond unit,
but it is recommended that workers wear rubber boots and gloves to minimize direct
contact with the sediments and facilitate cleaning.
The existing estimate of worker risk is based in limited data. In order to gain an
accurate estimate more data would be required. A new estimate may modify the
risk that was originally estimated. In order to minimize any risk, actual exposure to
the sediment is controlled by limiting worker access. Based on the information
available, the DOE, EP A and SCDHEC are being protective of human health and
the environment by being conservative and recommending the refilling and
maintaining of the pond, to reduce the potential risks, until more information
becomes available. .'
"4. We find it ironic thattlu! exposure of tlu! workers to the sediments poses tlu! greatest actual
risk, yet no"monitoring of the workers is required. Of all the money spent on qUflntifying the risk,
DOE is unable to quantify the actUfll exposure of the workers, nor compare tlu!ir exposure to other
workers. How can tlu!y caLL it a real risk, and yet not attempt to quantify it?"
Response:
The DOE has initiated several sampling and monitoring prograplS to be!1er assess the
radiation environment of PAR Pond. Most of these data are not yet available.
Please see #3 and the response to the letter.
"5. The risk to the environment was not clearly stated, however it was stated that no ill effects due
to tlu! exposure/uptake of either radiation or mercury has been observed in the three years the pond
was down. The EP A indicated that their primary driver was to protect tlu! species in the area.
Given the fact that no adverse impacts have been observed in three years, we feel that their money
would be better spent studying otlu!r areas at SRS. "
Response:
Although there is no evidence of harm to wildlife from uptake of CS-137 or
mercury there has been a noticeable increase in the uptake of cesium in some of the
animals and vegetation on the sediments. The uptake levels have not yet reached a
dose level where harm to wildlife will occur. The longer wildlife is exposed or can
be exposed to the sediments the greater the uptake of contaminants will be and the
greater the risk of physiological harm becomes. Wildlife monitoring will continue.
Also note that 1340 acres of aquatic habitat was lost (loss of the entire littoral zone)
during the drawdown. The impacts from the drawdown are currently more visible
than those associated with the contaminants in the sediments. Effects of the
drawdown were outlined in the lAPP.
"Risk to the Environment
6. After further discussion of who (humans or habitat) were at risk due to the lower pond, level,
it I,vas stated that the risk was not indeed a driver for the refill, hut rather the only driver was the
restoration ofrhe pond as all ecological resource. The SREL person indicated that Par Pond is a
RS-9
-------
source of study on threatened and endnngered species; that the drawdown had devastated an
invaluable wildlife sanctuary; that the population of ducks was vastly reduced; and finally that the
environmental quality could only be restored by refilling the pond. We believe that the value of the
pond as an ecological resource is valid, however we feel that scientific research should be funded
based upon it merits, not by blackmailing the regulators and DOE (who hold the taxpayers
checkbook) with the suspicion of harm to the environment. "
Response:
DOE and EP A agree that there is a potentiallong-tenn risk to both human health and
the ecology from the exposed sediments. Ecological receptors can be more sensitive
than human receptors and the risks are often difficult to quantify. However, it the
potential risk associated with the exposed sediments that is driving DOE to refill the
reservoir. The value of the ecological resource is an added benefit, but not one of the
criteria for selecting the proposed alternative.
"7. We a!so believe that it is faulty science to claim that the diversity of the wildlife habitat is a
result of 30 years of isolation, and that this is a "ru;ztural" habitat; this neglects the fact that for 30
years the government has pumped nutrients to the pond that otherwise would not have been there.
Surely anyone with a few billion dollars could create a similar habitat for study. "
Response:
Comment noted.
"Cost Effectiveness
8. The cost estimates provided were bogus at best, and the assertion that the preferred alternative.
is cost effective is ridiculous. A response to this comment that 'the regulations required that this
methodology be used' is another representation of comment number one. What we would like to
see included is a cost estimate that has at least a shred of credibility (you can also include the
regulatory required' version to satisfy the regulators)."
Response:
Please see the general response to the cost estimate. The cost estimate is as accurate
as possible and is presented in an industry accepted format.
"9.
The following non-conservatism's were observed in the cost estimate: .
. Using a 5% reduction in cost each year is absolutely ridiculous - use a minimal
inflation rate instead - like 2% in the other direction.
. The $360,000 estimate was called an incremental cost: did this represent all the
costs involved ;;r does it represent the added cost of pumping?
. The cost estimate does not include the whole path forward - like one member of
the public stated, we are jumping on a train, but no one knows where the train is
headed.
. DOE stated that they intended to pursue another interim action to allow pumping to
stop - if that is the case, then this IAPP should include the cost of preparing a
second IAPP in the estimate in order to fairly represent the cost of this alternative."
RS-lO
-------
Response:
Please see the general response to the cost estimate.
The 5% discount rate is not a reduction in the estimated annual cost but a way of
measuring the time value of money. It includes inflation.
The $360Klyr. represents PAR Pond's part of the operating cost for the river water
system.
The cost estimate does not and should not include the cost for the "whole path
forward" or the cost of preparing another set of CERCLA documents for a yet to be
determined action. These costs would be impossible to estimate since the scope of
any future action is unknown at this time. The "whole path forward" for PAR
Pond is dependent. upon many other factors besides the current CERCLA action or
any future CERCLA action (see page 1 of the Responsiveness Summary)
RS-II
-------
Letter from Mr. G. .T. Phillips to the EPA
M r. John Hankinson
Administrator
U. S. EPA, Region IV
345 Courtland Street
Atlanta., GA 30365
Dear Mr. Hankinson:
The reason for this letter is the public meeting I attended in Aiken, S. C. concerning the Interim
Plan for Par pond. I am not writing to Mr. Crane, who represented your agency, because he does
not have the authority to stop this wasteful project and also because Mr. Crane made it quite clear at
this meeting that he had made up his mind that he was going to approve refilling the pond. I
submit to you that he is °a public servant and is required to listen to the voice of the people. Four
people asked questions, and three of those four people were of the opinion that this project was 0
unnecessary. Another person responded that he worked for the ecology laboratory and that it was
necessary to fill the pond for the ducks, I would go along with this logic if it weren't for the fact
that Savannah River is a closed site and that it is not open to the public and therefore the citizens of
the United States do not benefit from being able to see these beautiful birds. H oweve r, these birds
have migrated to surrounding lakes where they are enjoyed by all.
I am writing to you to request that your agency implement alternative I, which is no action at all for
the following reasons: 0
1. There is no dtmger to human health, the animal population, fish, and ecology as pointed out
by Westinghouse personnel at this meeting. However, Mr. Crane stated that there was a threat to
the ecology. I went on record to ask Mr. Crane how he knew more about the dimgers at SRS than
the people who monitor the site daily. I also entered into the record information contained in the
Savannah River Environmental Report for 1993 Summary Pamphlet tho:t there were no dimgers
based upon the hypothetical individual who receives the maximum exposure from all pathways.
(See Appendix A). This report further goes on to compare the maximum dose from SRS releases,
both airborne and liquid, to the applicable standard and the releases never exceeded the applicable
standilrd. (See Appendix B) The Sportsmen's Doses (See Appendix B, page 16) shows that 1,553
deer and 147 hogs 'Hlere taken from the site and none of them has appreciable doses of cesium that
required them to be taken from the hunters. This entire report is full of information as (0 why
filling the pond is unnecessary, even though the hypothetical models were worst case scenarios.
Response:
SRS CERCLA units are evaluated with respect to both onsite and offsite risks
associated with individual operable units. In contrast, data presented in the SRS
Annual Environmental Monitoring Report (WSRC 1994) predominantly represent
the cumulative risks associated with all SRS operations to offsite individuals and
populations. These doses are associated with atmospheric and liquid release (e. g.
stream) pathways. Additionally, potential doses related °to the consumption of deer
and hogs taken during the SRS public hunts are calculated. The analyses presented
in the Annual Environmental Monitoring Report indicated that the radiological doses
associated with SRS operation are minimal, and confinn the Par Pond CERCLA
unit specific predictions that were presented in the Baseline Risk Assessment Using
Existing Data for Par Pond (BRAEDPP: WSRC 1992). Additional pathways, such
as the res us pension and offsite transport of contaminated soil particles, were
considered in the BRAEDPP~ these additional evaluations also indicated that (he risk
RS-12
-------
to offsite populations and individuals from the Par Pond Exposed Sediments was
within acceptable ranges.
The risk assessment under CERCLA (BRAEDPP) also included evaluation of the
risks to trespassers into the unit, SRS workers working on the unit, future residents
and organisms inhabiting the area. The BRAEDPP identified risk at, or higher
than, the 10-4 threshold for the future Par Pond worker, and the future Par Pond
resident, as well as potential risk for several components of the ecosystem that were
evaluated. Under current use scenarios, risks of 10-6 or higher were calculated for
the Par Pond worker, but not the trespasser. The available data indicated that
ecological components may also be at risk by occupying the exposed sediments.
Additionally, data collected by the Savannah River Ecology Laboratory (SREL)
after completion of the BRAEDPP indicated that Cs-137 uptake by from soil to
plants is higher than assumed in the BRAEDPP, thereby potentially increasing the
. risk from the exposed sediments. Because there are no current residents at Par
Pond, that scenario was not evaluated.
Thus, the two documents are not in conflict. Both documents conclude that there is
no unacceptable risk to offsite individuals, while risks to individuals and organisms
directly encountering the exposed sediment unit at Par Pond are above the threshold
criteria.
"2. The cost da1a in the report is incorrect. Westinghouse never got to discuss the cost datL1.
although I raised several questions about th£ validity of th£ infonnation. It was as if Mr. Crane
and Westinghouse did not want to discuss this information. However I find it suspicious that after
the meeting adjourned and we were no longer on record, that Mr. Clark and his assistant came up
to me and started a conversation. I asked him if h£ thought that the $5.5 million life cycle cost was
correct, because when multiply 30 years by $360,000 a year your result is $10.8 million. Mr.
Crane stated, off the record, that th£re must be a mistake and that Westinghouse should have added
5 percent each year. Once again why did he have this discussion with me off the record. I suggest
to you tJwt th£ public is not being told th£ true cost of th£ project and EPA and SCDHEC are
condoning these inaccuracies by not ensuring that th£ information in th£ lAP P is correct. I also
find fault with the estimate because there is no escalation for inflation. "
. Response:
Please see the general response to the cost estimate. There was no mistake in the
calculated present work cost.
"3. It is the responsibility of EPA to make sure that there is a significant risk to th£ public first
and the animals last before you require DOE to spend money that is needed elsewhere. We have
such a significant risk at the Site. the deterioration of plutonium storage containers. and it will
endanger the lives of the workers as well as the ecology. (See Appendix C) Let's put the money
where it is most needed especially since Secretary O'Leary is talking about cutting billions from the
budget for environmental remediation. Please act responsibly and say no to the pond so [lUll this
money can be used to protect 20,000 human lives at the site. " .
Response:
Please see response to comments #3, 4, 5, 6 (TRIM cornments)on pages 8-10 of
the Responsiveness Summary.
RS-13
-------
"I believe the three reasons given above are sufficient to choose alternative one or have another
public meeting and present the true facts. Although I believe the second alternative is a waste of
the taxpayers dollars. Further, I believe that Alternative I meets all the criteria stated in the IAPP
page 11-2.
Another matter that I wish to bring to your attention is that Mr. Cran£ assured me that there would
be a public meeting on SRS's Groundwater trealment plans, although the announcement (See
Appendix D) says that a meeting will be held only if the public requires it, because I requested one.
I have not seen this plan yet but will request a copy of it for my review. Mr. Rash from SCDHEC
also gave me the assurance that a public meeting will be held. Please let me know by December
27th when you pIan on scheduling this meeting. Look forward to hearing from you and Mr.
Crane. "
Response:
Comment noted. Alternative 1 does not meet the required criteria (9 criteria). This
is stated in sections IV.C and IV.D of the IAPP.
RS-14
-------
Letter from Mr. F. Ward Whicker to the EPA
"RE: Interim Action Proposal Planfor the
Par Pond Unit (WSRC-RP-92-1170)
I wish to register public comments on the Interim Action Proposed Plan for the Par Pond Unit:
1. I strongly support preferred Alternative 2, refilling and maintaining Par Pond to the original
200 ft. level. ,
2.
I support Alternative 2 because it is:
a.
b.
c.
d.
The least costly alternative.
The most environmentally-sound alternative.
The most timely action to reduce human health risks.
Very feasible since the dam has already been repaired.
3.
4.
I support the pumping of Savannah River Water to fill and maintain the level of Par Pond.
I support pumping of Savannah River Water to fill and maintain Par Pond because:
a. It will restore lost nutrients which will reduce the biological mobility of the
main contaminant, 137 Cs.
b.
The nutrients are crucial to the fUll biological recovery of the ecosystem.
c. The pumping will be required to prevent fluctuating water levels that would
periodically expose large areas of contaminated sediments.
d. Fluctuating water levels have been shown elsewhere to enhance the
methylation rate of mercury, leading to higher uptak£ in fish and waterflow.
e. Periodic pumping will have similarly positive ecological benefits and reduce
contaminant mobility in other portions of the water distribution system. Examples
are Pond 2, Pond 5, Pond C, and the Canal itself. Furthermore, the maintimance of '
the water distribution system is crucial to the maintenance of L Lake, a large
reservoir that is also of immense ecological value.
f. While the costs of pumping and maintenance are significant, the ultimate
costs of not pumping are likely to be far greater because of regulatory
requirements for site characterization, human health and ecological risk .
assessments, and likely remedial actions that would ultimately be necessary under current
risk guidelines.
I respectfully request that these comments be duly registered and considered in your deliberations. "
Response:
The comments presented in the letter have been noted and supports the preferred
alternative. SRS concurs that at this time, alternative 2 is the most cost effective
and protective alternative.
RS-15
-------
Letter from Mr. S. Booher to A. B. Gould. DOE
"Subject: Public Comment on the IAPP
Dear Mr. Gould,
Having read your IAPP. I have no personal objection to your Alternative 2.
However, no where in the IAPP did I see you address the subject of On Going Studies a1 the
Savannah River Ecology Lab.
REQUEST: I request that you investigate the current studies being conducted of Par Pond to
insure that th£re at NO studies on going that would be negatively impacted by Alternative 2. A
statement to this effect needs to be added to your Proposed Pian.
If you find there are studies then this needs to be a part of the decision making process.
If you find there are studies then this needs to be a part of the decision making proces.s.
You may wish to delay your Alternative 2 until these studies are completed. "
Response:
Comments in the letter have been noted. Although the research that has been and is
being performed on the sediments is valuable in it's own right; the research being
performed on the exposed sediments is out of the scope of this interim action,
unless it directly effects the CERCLA action. . Any studies being .performed on the
sediments are temporary in duration; i.e. as long as the pond level is down the
studies can continue. However, most of the studies can continue after the pond is
refilled. Few require the lower water level. The temporary nature of the drawdown
has been known since it was initiated. Many of the current research programs were
initiated as a result of the drawdown, while others are continuations of work begun
before the drawdown. Refilling the reservoir will create other research
opportunities.
RS-16
-------
Letter from Mr. E. F. Girardeau to the EPA
"SRS Remedial Project.Manager
U. S. EPA, Region IV
345 Courtland St.
Atlanta, GA 30365
Dear Sr.,
I attended the meeting last night, December 14, 1994, concerning the PAR Pond Interim Action
Proposed Plan. Following are my comments.
I felt that the material concerning the situation was well presented and questions of importance
answered satisfactorily. From a personal opinion standpoint, I feel that the water should be
returned to the 200ft. .level. By doing so 1340 acres of sediment would be covered and eliminate
the potential problems that could come from the huge amount of sediment - problems to humans as
well as wildlife. Why leave something exposed that mayor may not be safe? Let's go the safe
way be covering it with water since other methods are too expensive.
My interest is because I am an owner of a hunting club approximately ten (10) miles from PAR
Pond. We primarily hunt ducks which we. have suspected roost at PAR Pond. This was
confirmed last night by Dr. Brisbin (Savannah River Ecology Lab) who described PAR Pond as
holding more diving ducks than (Lake Murray, Santee, etc.) any holding area in the stllte of South
Carolina. He stated that the numbers have been cut considerable since the pond was brought down
in 1991. During this period the ducks that we have had have been reduced more. than half. This,
of course. is our concern. It was refreshing to hear from Dr. Brisbin that the ducks are safe to ea1
since this is a concern of our hunters.
The only suggestion that I have to improve your meetings is to put a limit on how long one person
can address the group. Last night one person read meaningless nuri7hers from a previous report
that was not available to the rest of us and it was evident to me that the purpose for his being there
was to bash EP A.
Then the lonely little man from Augusta, a professional "letter to the editor" type, talked for 15 or
20 minutes with a goal to protect the people of Savannah when.in reality he needed to be heard for
his" own. ego. These types hold down participation of the general public.
I appreciate having the facts furnished at this meeting and hope that the action taken will be to bring
the water level back to a full 200 foot level. .
Edward f. Girardeau"
Response:
The comments in the letter have been noted and support the preferred alternative.
RS-17
-------
Letter from Mr. Todd V. Crawford to the EPA
"SRS Remedial Project Manager
U. S. EPA, Region IV
345 Courtland Street
Atlanta, GA 30365
Ref" Interim Action Proposed Planfor PAR Pond
Dear Sirs:
I believe that the action to be selected should be between the two suggested alternatives (SRS
Environmental Bulletin, Vol. 5, No. 26, December 1, 1994). Refilling PAR Pond to its original
level of 200 feet above sea level and maintaining it there at a anruu;zJ cost of about $360,000 for
river water pumping can not be justified by public risk reduction." Leaving it at 181 feet above sea
level can not be justified either as that would require the continual operation of systems to move
water from PAR Pond into Lower Three Runs Creek. During heavy periods of rain that could also
cause movement of Cs-137 contaminated sediments in Lower Three Runs Creek due to large
discharges'of PAR Pond water into the creek to mai~tain the 181 feet elevation.
Instead, I believe that allowing PAR Pond's elevation to fluctuate between 181 and 200 feet with
the weather is the better choice. I understand that the equilibrium level has not been clearly defined
yet but the best estimates place it in the 190 to 195 feet range. This would minimize costs
(although some cost would still be incurred to maintain a minimum flow in Lower Three Runs
Creek). In this respect, PAR Pond would then be mpnaged like Pond B (which also contains
contaminated sediments) has been since the 1960's. A nearly constant minimum flow in Lower
Three Runs Creek below the PAR Pond dam would also minimize movement of contaminated
sediments in the creek and adjacent shore areas which would then be covered by vegetation. The
Lower Three Runs Creek corridor is more accessible 10 the public than is PAR Pond. I believe that
PAR Pond and Lower Three Runs Creek need to be consitkred as a system when minimizing
possible public impacts and costs. "
I lookforward to receiving your response to this suggestion.
Todd V. Crawford"
Response:
The comments in the letter have been noted. Please see the general response on
page I of the Responsiveness Summary.
RS-18
-------
Letter from I.E. Coward II to the EP A
"Mr. I. E. Coward 1I
Aiken, SC 29801
Gentlemen,
Par Pond at the SRS is one of the best ecological areas in the southeast for wildlife native to
the region. I highly support the refilling to its original level in order to cover and shield any
exposed contaminants. Every effort should be made to decrease the short term risk to
public health and the environment.
Yours Truly,
Ira E. Coward"
Response:
The-comments in the letter have been noted and support the prefen-ed alternative.
RS-19
------- |