United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R10-93/071
September 1993
&ER& Superfund
Record of Decision:
Bangor Naval Submarine
-------
4.
50272-101
REPORT DOCUMENTATION 1'. REPORT NO.
PAGE EPA/ROD/R10-93/071
Title and Subtitle
SUPERFUND RECORD OF DECISION
Bangor Naval Submarine Base, WA
Second Remedial Action
Awhor(a)
~
3. ReclpIent'a Ace_Ion No.
&
Report Data
09/30/93
&.
7.
8.
Performing Organization RepC. No.
8.
P8rtormlng Organization Name and Add,....
10
Proj8c:t TaalclWortI Unit No.
"
11. Contract(C) or Grant(O) No.
(C)
(0)
12. ~ng Organization Name and Add.....
U.S. Environmental Protection
401 M Street, S.W.
Washington, D.C. 20460
Agency
13. Type of Report .. Period Covered
800/800
14.
15. Suppl8m8ntary Hal.
PB94-964608
18. Ab8tract (Umlt: 200 words)
The Bangor Naval Submarine Base site is located approximately 10 miles north of
Bremerton, Kitsap County, Washington. Land use in the area is predominantly
undeveloped or residential, with Hood Canal bordering the site. In 1944, the Base was
established to provide a deepwater transhipment point for ammunition and explosives,
over~aul ammunition, and dispose of unserviceable or dangerous ordnance. A segregating
and reconditioning facility was located onsite where ordnance returned fr~m ships was
separated and inspected. Demilitarization of ordnance at the site began in 1958,
reached its peak between 1966 and 1970, and ceased in 1978. From 1958 to 1973, a
metallurgical laboratory (FML) located in the south-central portion of the Base was
used for testing brass projectile shell casings that were coated with mercurous nitrate
and heated. The procedure reduced and volatilized the mercury, which then condensed in
the walls of the metallurgical laboratory building. It is estimated that roughly 100
pounds of mercurous nitrate were consumed in the testing procedure. In 1973, the
laboratory was demolished, and the debris was buried in an area now known as "Site 5."
This. site is believed to be in the south-pentral portion of the Base, in an area of
barricaded railroad sidings, although the exact location of "the debris cannot be
confirmed. The. area where the FML was located was rebuilt as the Base's central corps
(See Attached Page)
17. Document Analyala a. De8crlptors
Record of Decision - Bangor
Second Remedial Action
Contaminated Medium: None
Key Contaminants: None
Naval Submarine Base, WA
b.
IcI8ntlfillrs/Op8noEnded Terms
c.
COSAT1 Fl8lcUGrvup .
18. Availability Stat8rn8nl
19. Security Class (Thl. Raport)
None
31. Security aua (This P.age)
None
21. No. of Page.
34
22. PrIce
-------
EPA/ROD/R10-93/071
Bangor Naval Submarine Base, WA
Second Remedial Action
Abstract (Continued)
area, and is now a paved parking lot between a ,child-care center and the chapel. In 1980,
as part of the Department of Defense's Installation Restoration Program (IRP), the' Navy
conducted studies at the Base to assess environmental impacts from site operations. A
1991 ROD addressed onsite containment of ground water, as ,OU2. This ROD addresses a final
remedy for Site 5, the former FML debris disposal area, as OU5. In 1981, site
investigations performed at Site 5, as part of the RI, initially suggested the possible
presence of residual mercury in onsite soil; however, concentrations were determined to be
consistent with naturally occurring levels. Therefore, there are no contaminants of
concern affecting this site. '
The selected remedial action for this site is no further action.
the risk assessment, mercury concentrations detected at Site 5 do
unacceptable risks to human health or the environment. There are
costs associated with this ,no action remedy.
PERFORMANCE STANDARDS OR GOALS:
Not applicable.
~
Based on the results of
not present any
no present worth or O&M
-------
1, \ ~ . ~ t' .,
DECLARATION OF THE RECORD OF DECISION
SITE NAME AND LOCATION
. i
Naval Submarine Base, Bangor
Operable Unit 5
Bangor, Washington'
STATEMEl\,. OF BASIS AND PURPOSE
This decision document presents the selected action for Operable Unit (OU) 5 at the
Naval Submarine Base (SUBASE), Bangor, in Bangor, Washington. chosen in
accordance with the Comprehensive ~nvironmental Response, Compensation, and
Liability Act (CERCLA) as amended by the Superfund Amendments and
Reauthorization Act (SARA), and, to the extent praCtical, the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP). OU 5 consists of Site 5, the
demoiished former metallurgical laboratory (FML) rubble, with confirmation sampling at
the FML original location. This decision is based on the administrative record for the
sites.
The lead agency for this decision is the United States Navy. The United States
Environmental Protection Agency (EP A) approves of this decision and, with the
Washington State Department of Ecology (Ecology), has participated in scoping the site
investigations and in evaluating alternatives for remedial action. The State of
Washington concurs with the selected remedy.
DESCRIPTION OF THE REMEDY
No action.
DECLARATION
No remedial action is necessary to ensure protection of human health and the
environment. A 5-year review is not required.
Using EP A guidelines and the information developed during the site investigation, the
Navy evaluated the potential adverse effects to human health and the environment
associated with exposure to site chemicals. The potential exposure of workers and
residents to chemicals detected at each site was estimated for current and future
scenarios. The evaluation, performed according to EPA's NCP and policy guidance,
indicated that no unacceptable risks are present at the tWo sites. This evaluation
supports a decision for no action at Operable Unit 5.
-------
Signature sheet for the foregoing SUBASE, Bangor, Operable Unit 5, Remedial Action,
Record of Decision between the United States Navy and the United States
Environmental Protection Agency, with concurrence by the Washington State
Department of Ecology.
~ '
~~
9-3
-------
Signature sheet for the foregoing SUBASE, Bangor, Operable Unit 5, Remedial Action,
Record of Decision between the United States Navy and the United States
Environmental Protection Agency, with concurrence by the Washington State
Depanment of Ecology.
i
/~ tf/ J;.f~
Gerald Emison
Acting Regional Administrator, Region 10
United States Environmental Protection Agency
9-~9--93>
Date
-------
Signature sheet for the foregoing SUBASE, Bangor, Operable Unit 5, Remedial Action,
Record of Decision between the United States Navy and the United States
Environmental Protection Agency, with concurrence by the Washington State
Department of Ecology.
"J
(}
-------
SUBASE. BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
CTO 0038
Record of Decision
Date: 09/22/93
Pagel
,
DECISION SUMMARy
1.0 I~'TRODUcnON
Naval Submarine Base (SUBASE), Bangor was listed on the National Priorities List
(NPL) on August 30, 1990. In accordance with the Comprehensive Environmental
Response, Compensation, and Liability ACt (CERCLA), as amended by the Superfund
Amendments and Reauthorization A~ (SARA), the United States Navy (Navy)
perfonned a remedial investigation/feasibility study (RI/FS) to characterize the nature
and extent of any residual chemicals of concern. In the case of Operable Unit (OU) 5 at
SUBASE, Bangor, the Navy's evaluation of potential adverse effects on human health
and the environment indicated no unacceptable risks at the site for either current or
future uses.
2.0 SITE NAME, LOCATION, AND DESCRIPTION
SUBASE, Bangor is located in Kitsap County, Washington, approximately 10 miles north
of Bremerton on Hood Gmal (Figure 1). Land surrounding SUB~E, Bangor is
generally undeveloped or supports limited residential use. OU 5 is located in the south.
central portion of the base. It consists of Site 5, the disposal location for rubble from
the demolished former metallurgical laboratory (FM!.) (Figure 1). Confirmation
samples were taken at the original location of the FM!. to make sure the area was clean
(Figure 2). Mercury was of potential concern at both areas.
The investigation of the FML site consisted of drilling five soil borings to a depth of 15
feet. Soil samples were collected from each boring at intervals of 1.0 to 25, 6.0 to 7.5,
and 14.0 to 155 feet These samples were analyzed for total metals to determine the
possible presence of residual mercury. Concentrations of metals found in FML soil
samples were consistent with naturally occurring metals in SUBASE, Bangor soils.
Figure 3 shows the location of the soil borings at this FML site.
The remedial investigation of Site 5 included sampling the site soils, stormwater and
sediment runoff, downgradient groundwater, and soil vapor. A soil vapor survey was
performed in an attempt to pinpoint the burial location of the FML rubble. The soil
-------
.'
: '. ".:." '::::::::.,::; :'[[[-::;:;:::~;::::'.:::::;.::::;:::;:~"::::>;:::.::".;:':;:':::'
..'.,rL~
~#l '-&8 I
~ t
,,~~ :
"I 1 ---r
! I i
". :"\. : I
'1 jl '\: :
. ,~';ji it f-.-~'L-I
.t ! jZ j :
, $: :: ..J
J~.'bN; i
I' . : -- 1 --
...- . .
..... .. / SUBASE, I
x,:~:,,"":,m',~.......' BANGOR --.,.1
':';';';':-:-:-:';"';';:";':';':':':-j' # .
?:.::;yt:::?~''-t,V/! ! Ii
" : I:' :.
({ i iz ~ ir
-, ~'"'""" : :.,
--" ~I &. :... :-
,.~. .....---u
'~ i~': trT~!
~ - ~! jj
\ 'I: :.
j L-)~
~ r-+~~t
~ i: j-ie.,!
h r--J! I
~,. ~~ ! Aia
16 .
~\ I
\\ t \../1 .
\/1 ~
l~
r..
r.
+
NORTH
o
3000
6000
"II,.
"
CLEAN
COMPRBiENSlVE
LONG-TERM ENVIFD6tENTAL
ACTION NAVY
Figure 1
-------
81
,.
RECl9T1ONAl
COMPlEX
~
. ,
,
"
,
~
"
,
,81
. ;
'--..-......---- .
, .
: .
Fonner
Metallurgy
Laboratory
,81
. .
:
co
. ,
,.
"
:1150
. .,~.
1
a:
I
J
o
co
...
..
Gate 4
o
I
+
NORTH
500
I
Scale In Feet
Con8Dcn i1 flit
CLEAN figure 2 eTO C038
COIFREJENSIVE LONG- StEASE, Bangor
TERU ENVIAOt&tEHTAI.. Site Map. Former Metallurgy Laboratory waslinglon
ACTION NAVY ROD
-------
r'.
Pompano Street
-----
'-
Possible Sites
of FML
o
lEGEND
-<>- SB01 Dili1g Location
..
NORTH
0 50 100
I
Scale k1 Feet
{\
CLEAN
COLtPREHENSIVE L~
1ERM ENVR)NIofEHTAl
ACmN NAVY
Figure 3
location of Soli Borings at Fonner
Metallurgy Laboratory Site
CTO 0038
SUBASE. Bangor
WastingCon
ROD
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D.9295
era 0038
Record of Decision
Date: 09/'12/93
Page 5
vapor survey analyzed mercury concentrations in air samples obtained from subsurface
soils at various locations on the site. A backhoe was used to excavate possible burial
locations identified in the survey, but the FML rubble was not found.
A nested groundwater sampling well was installed downgradient from Site 5. The static
groundwater level was approximately 117 feet below ground surface. Groundwater flows
are to the northwest in the vicinity of Site 5. No groundwater sampling was performed
near the FML The area around Site 5 generally consistS of Vashon Till, which may
reach a thickness of up to 40 feet. 'J11e till is underlain by Vashon Advance Sand.
2.1
FML SITE
The metallurgy laboratory was tom down in 1973 during construction of the submarine
base. The area where the metallurgy laboratory was located was rebuilt as the base's
central core area. The area is now a paved parking lot between a child-care center and
a base chape~ located between Pompano Street and Pickerel Circle. Since the
demolition of the FML, the area has been regraded, paved, and landscaped. Figure 2
shows the site location.
2.2
SITE 5
After the FML was demolished, building rubble was reportedly buried in an area
designated for disposal of construction debris. The disposal area is believed to be in the
nonhern portion of the western barricaded railroad siding area, which is located in the
south-central part of the base. This area consisted of 20 barricaded railroad sidings.
Several years after the initial demolition, the foundation of the FML was reportedly
buried in the southern portion of the western barricaded railroad siding area. The
abandoned barricaded railroad sidings were filled with construction debris and soiL The
exact locations of the buried rubble could not be confirmed by historical records,
personnel interviews, or aerial photographs.
The terrain of Site 5 is rolling and uneven, covered with an array of successional, weedy
plant species. The soil varies from sand to grave~ and there is no vegetation indicative
of moist or wet habitat. The area is sUITounded by a dry Douglas fir forest with a
relatively low and open understory. Surface water runoff appears to flow unevenly across
the entire site. There are no well-established drainage channels, although roadways lying
below small berms created by the fill material probably channel stormwater to a small
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.5. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
era 0038
Record of Decision
Date: 09/12/93
Page 6
"
stream to the south. Figure 1 depicts the general site location and geographic setting of
Site 5.
3.0 SITE HISTORY AND ENFORCEMENT ACTMTIES
3.1
SUBASE, BANGOR, HISTORY
The U.S. Naval Magazine Facility Bapgor was established in 1944 to provide a
deepwater transhipment point for ammunition and explosives. It became the primary
command for ammunition activities in Puget Sound in 1948.
The primary role of NAD Bangor was to provide transhipment and supply of fleet
ordnance, which also included overhaul of ammunition and "disposal" of unserviceable or
dangerous ordnance regardless of source (Hart Crowser 1989). Bangor included a
segregation and reconditioning facility, where ordnance returned from ships was
separated by type and inspected for serviceability. Demilitarization of ordnance at
Bangor was begun about 1958 (NEESA 1983).
The Polaris Missile Facility Pacific was added in 1963. Ordnance operations including
demilitarization continued and reached a peak between 1966 and 1970 as a result of the
Vietnam conflict. With a recall of troops from Vietnam in 1970, the sbiploading
operation was transferred to Naval Weapons Station (NWS) Concord, and Bangor was
linked with Naval Torpedo Station (NTS) Keypon. Concerns over potential
environmental hazards were raised at that time, and a variety of studies were
undertaken. Demilitarization operations continued on a limited basis until about 1978.
Bangor again became an established facility following its selection as the: Trident
Submarine homepon in 1973. .
3.2
HISTORY OF PREVIOUS SITE EVALUATIONS
3.2.1 Assessment and Control of Installation Pollutants
In September 1980, in response to CERCLA, the Navy initiated the Navy Assessment
and Control of Installation Pollutants (NACIP) program. The NACIP program is part of
the Department of Defense's Installation Restoration Program, which corresponds to
EP A's CERClA program. The objective of the, NACIP program is to identify, assess,
and control environmental contamination from past hazardous materials storage,
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09/72/93
Page 7
transfer, processing, and disposal operations at Naval facilities. The NACIP program at
SUBASE, Bangor superseded the previous ACIP program investigations. In 1981" an
initial assessment study (lAS) performed under the NACIP program (NEESA 1983)
recommended further investigation of Site 5 to determine whether the site was
contaminated.
In 1986, Congress enacted the Superfund Amendments and Reauthorization Act, which
brought about changes in the Navy's NACIP program. The Navy was required to modify
its existing NACIP program to be coqsistent with EP A program guidance and
terminology.
Rather than develop verification and characterization reports for the sites at SUBASE,
Bangor, as had been planned under NACIP, the Navy phased into the EP A's Remedial
Investigation/Feasibility Study (RI/FS) program, which involves a phased progression
from initial scoping and site characterization to an evaluation of remedial alternatives.
A current situation report (CSR) was completed for SUBASE, Bangor in 1989 (Hart
Crowser 1989). The CSR indicated that neither the existence nor location of mercury at
Site 5 could be confirmed with available soil or water data. However, available data did
indicate that mercury was likely to be buried in the vicinity and, unless disturbed, would
remain contained below ground. The CSR recommended additional soil testing and
stormwater runoff sampling. '
On JanuaI)' 29, 1990, the Navy, EPA, and Washington State Department of Ecology
(Ecology) signed a cooperative three-party Federal Facility Agreement (FF A) to study
and clean up possible contamination at SUBASE, Bangor. The FF A assigned Site 5 to
OU5.
A site investigation (SI) was completed for OU 5 in September 1992 (URS 1992af The
SI conducted a field examination of au 5 and concluded that mercury vapor was the
principal contaminant at Site S.
An RI/FS was completed for au 5 in December 1992 (URS 1992b). Tbe RI/FS
evaluated whether residual mercury remains in the environment at OU 5, and, if present,
whether it posed a threat to human health or the environment. The RI/FS identified no
chemicals of concern at the FML site and concluded that mercury concentrations
detected at Site 5 do not present a significant risk to human health or the environment.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
era 0038
Record of Decision
Date: 09/'12/93
Page 8
4.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION
The Navy, EPA, and Ecology provided information and solicited comments from tbe
public concerning tbe proposed plan for remedial action for OU 5 tbrougb a public
comment period, a response form, and a public meeting and by maintaining repositories
of information where residents could review documents and materials related to
investigations at SUBASE, Bangor. The community relations plan concerning OU 5 is
available for public review in the information repositories at the Central Kitsap Regional
Library and tbe SUBASE, Bangor B~.ancb Library. (Access to SUBASE, Bangor, is
restricted to authorized personnel.)
In February 1993, the Navy, EPA, and Ecology published The Proposed Plan for Operable
Unit 5 (URS 1993). A notice of availability of the proposed plan and public comment
period was placed in The Sun (Bremerton) on February 24, 1993. In addition, the
proposed plan was placed in the administrative record and mailed to all on the mailing
list. SUBASE, Bangor. periodically issues fact sheets discussing remedial activities at all
operable units at the installation. The public comment period on the proposed remedial
action extended from February 24 to March 26, 1993.
A public meeting to discuss remedial action and obtain comments was held on March 4,
1993, at the Olympic View Community Center in Silverdale, Washington. There were 37
people in tbe audience (including Navy, EP A, and Ecology personnel and a court
reporter) and 6 people on the panel. Seven comme~ts were received. Responses to
public comments are contained in the Responsiveness Summary (Appendix A).
Repositories of information are maintained at the following locations:
Central Kitsap Regional Library
1301 Sylvan Way
Bremerton, Washington
(206) 377-7601
Bangor Branch Library
Naval Submarine Base, Bangor
(206) 779-9274
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.5. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09 /Zl/93
Page 9
The administrative record is on file with:
Engineering Field Activity, Nonhwest
1040 N.E. Hostmark Street
Olympic Place n
Poulsbo, Washington
(206) 396-5984
.
,
5.0 SCOPE AND ROLE OF OPERABLE UNITS
Two NPL sites are located at SUBASE, Bangor. The first is Bangor Ordnance Disposal,
Site A (OU 1), which was listed on the NPL on July 22, 1987. On August 30, 1990, the
remainder of SUBASE, Bangor-including an additional six operable units comprising 20
known or suspected hazardous waste sites-was listed on the NPL 1bis record of
decision addresses one of these operable units, au 5, which consists of Site 5.
The risk assessment for noncancer and cancer risks at au 5 shows that the original FML
site and Site 5 present no significant CUITent or potential threats to human health or the
environment and do not warrant further action.
6.0 SUMMARY OF SITE CHARACTERISTICS
This section presents an overview of site contamination and potential routes of exposure
posed by conditions at the two sites.
The FML site was used for testing brass projectile shell casings. Tne casings were
coated with mercurous nitrate and heated. The procedure reduced and volatilized the
mercury, which then condensed in the walls of the metallurgical laboratory building. It is
estimated that during the years of operation (from approximately 1958 to 1973), roughly
100 pounds of mercurous nitrate were consumed in the testing procedure. retained within
the building. and could be present in the rubble of the FML (NEESA 1983; Spencer
1983).
Site 5. as described in the initial assessment study (NEESA 1983). the current situation
repon (Hart Crowser 1989), and the Federal Facility Agreement, is the disposal location
for the FML rubble, formerly designated Building 274. Rubble from the building was
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09/12/93
Page 10
reponedly disposed of in the former barricaded railroad sidings located in the south-
central ponion of the base. Aerial photographs of the Site 5 vicinity suggest that major
disposal and grading activities began at the site between 1975 and 1977 (Hart Crowser
1989). However, historical data, aerial photographs, and site investigations did not
reveal the exact location of the FML rubble within the former barricaded railroad
sidings.
Data on the chemical characteristics of the Site 5 environment prior to the current
investigation consisted of one surface. water sample collected in 1983 and two surface
water composites, two surficial stream sediment composites, and five soil samples
collected from test pits in 1987. The 1987 surface water and stream sediment samples
were obtained by compositing individual samples colleCted from five ditch locations on
either side of the access road through the site. These samples were collected during a
storm sufficient to generate sheet-flow runoff.
The surface water sample collected in 1983 is believed to have been collected from the
surface water drainage ditch at the site's downstream (southern) boundary. This sample
was submitted for mercury analysis. Because of inadequate documentation of the
analytical result, the reponed value may not be valid. The laboratory repon did not
document the analytic methods and units of reporting, and the validity of this data is
questionable. Surface water samples collected subsequent to 1983' were gathered in an
attempt to duplicate the results of the Navy's 1983 sampling that tentatively identified
mercury in surface water. .
Water samples collected in 1987 were submitted for the determination of 84 constituents
including metals, ordnance, volatile organics, pesticides, herbicides, and polychlorinated
biphenyls (PCBs). Surficial sediment samples were analyzed for total mercury. The
surface water samples did not deteCt mercury above:a level of 0.1 p.g/L Funhemiore, .
neither surficial stream sediment nor soil samples coUected during the assessment
exhibited mercury concentrations above background ,levels for Puget Sound soils.
Five other metals (beryllium, chromium, copper, lead, and nickel) were deteCted in the
surface water. The presence of these other metals in Site 5 surface waters, sediments,
and soils is consistent with the presence of metal wastes from refuse not associated with
the FML rubble. The measured levels of these metals were similar to those reported in
regional residential runoff (Hart Crowser 1989). Figure 4 shows the surface water and
sediment sampling locations at Site 5.
-------
'I
A..., ""... ,"
" , . , ,
"" '. .I / ','
." :i ~\
'\..( ! ! I,
, l' "
A --. 'l~ "
, '. "- "
" "'; ~': "
\... .~~ -- "
,:: ! : "
~ t .: --- "
.';. ~ I ;;,.--:~.... "
<. " : I, .... , "
e ~ : Ii , , ,
~ ~J '\ "
,""" , ,.}'. \', ,.,,'
'''.. .;~H ',-""..----------'
"-:'11 ,~
"" ~': /7 ,',' ~Fbad
~. ~I i; II ..
"':'" ~ !! ,',' i;s
I'J.~ /: "
'''"t i.:
<.". "1 r ::
. , \ \ .-
'" ". \\~! \~,
" .,~ ~ ,\
.~\" : .! "
.' II : : "
~" ./! I'
I"(~ ..; "
II~ :: II
-. , I ,':": "
;('" .!,- "
". "~.,, ~,
'. , '\T.' "
, '" '\iti: ,,' \
'. \\) '., I
"?I /:"
1rj; : j II
1\: '! "
II~ !! I'
"" II.:.,.: '\
". II , l. "
"\ ~- "
, '. \ ;;. "
'. ~:- '"" II
,\ ~ !,I II
~1 " II
.~- /: II
. ~"'''''~.'
,~: -:.,':".."
(~ !! ... \
~?:' "
"'" '.' 'p. ........
<\." I~:; '\
....., I;':=- \ I
'." I~- .~'I
'\\~!1 ff I,
~! f /,'/
.~ !!"
~-';'"
,/' &~I "
'- '\. ,\."I'-~~_-
'. '. 1'1\ I ...........
\. " ~" I: 'I~
,.~ '\ jj I' : .' "
FII.~ II;. I,
~.111\"! II
~ . t,j 0 FII.~
..' '\ i'" ~, FII.~
.." ~I "
,. ~ i'" I I
='" ';" --. II
~ ,t ,I / \,
~ . II~' II
F1I...sW .~" /" .: I I
;;. ,~ :
~~ \",
.:.~
('-. , .~ 1
\." :..,\
'..', .:-11 fe ",
'- ~ ,. tt/ '
,~ ! '14' /
... I" :
.~'I. !
;. 11
- ~~
\t~&
11"
.. "
. II
1 "
RIl-S0.4a2-U ~ II
F1I..sw.Ga2-U \r II
; "
R4.-SOQ)t-U \.11
R4.~1
~
LEGEND
.£ SI.rtace WZ8r1SeciIiU
~ I.oc:IIian
'., Fonner BarrieatId
\Rallaa:lSiq
CLEAN
COUPREHENSIVE LOtG-
TERM EHVIIDIUENTAl
Ar.TDI NAVY
Figure 4
Surface WaterlSediment Sampling
Locations at Site 5
eTO 0038
SUBASE. Bangor
Washington
-------
SUBASE, BANGOR. OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09/12/93
Page U
In the 19805, nine test pits were excavated to the base of fill materials and into Vasbon
TilJ in various parts of the abandoned barricaded sidings. Five soil samples were
selected for chemical analysis in places where rubble-possibly from the FML-was
found. No mercury above background concentrations was found in any of the test pit
samples. Cadmium and zinc were present in Site 5 soils at levels higher than normally
occur in Puget Sound soils. The incidence of these metals in Site 5 soils is consistent
with the presence of metal wastes not associated with the FML rubble.
In 1992, a soil vapor survey was condpCted with field instrumentation during the site
investigation of Site 5 (URS 1992a). Soil vapor samples taken at a depth of 10 to 15
feet below ground surface indicated the presence of mercury vapor.
The remedial investigation subsequently conduCted at the FML site and Site 5 (URS
1992b) consisted of the following components and fipdings:
.
FML Site
Identifying the original location of the metallurgy laboratory through
aerial photographs, interviews, and construction maps
Drilling five soil borings to 15 feet below the 'asphalt surface.
(Fifteen samples [three from each boring] were colleCted and
analyzed for total mercury. In addition, seleCted samples were
analyzed for ordnance compounds.)
Flndings: Mercury concentrations in FML site soils ranged between 0.04 mgjkg
and 0.08 mg/kg in 14 of the 15 samples. Only one sample (SB05, at a depth of
1 to 2.5 feet) at 0.63 mg/kg exceeded background concentrations. .
.
Site 5
I~
Ii
I,
!'
,.
Reviewing aerial photographs and historical records in an attempt to
locate the metallurgy laboratory rubble disposal area within the
abandoned barricaded sidings
Sampling surface water runoff and sediments in an attempt to
duplicate earlier sampling by the Navy that had tentatively identified
the presence of mercury
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
era 0038
Record of Decision
Date: 09/12/93
Page 13
Conducting a soil vapor survey in an attempt both to detect the
presence of mercury in the barricaded railroad sidings and to locate
the FML rubble. (Figure 5 shows the boundaries of the soil vapor
survey at Site 5.)
Excavating test pits at the locations with the highest mercury vapor
detections in an attempt to locate the buried FML rubble (based on
field screening with a mercury vapor sensor, soil samples were taken
from the test pit~d sent to selected laboratories for analysis)
Conducting a followup soil mercury vapor survey at selected
locations to determine whether the mercury vapor concentrations
detected during the initial survey, using field instrumentation,
represented localized accumulations of mercury vapor or whether
mercury vapor was widely dispersed within fill materials
Conducting a third soil mercury survey consisting of long-term (1 to
8 hour) pumping using sorbent tubes, followed by laboratory analysis
Sampling groundwater collected from a previously installed
downgradient nested well pair. (Two samples were collected.
Groundwater was found in two aquifers: one shallow and the other
at sea level. Well F-MW-43 was screened near the base of the
shallow aquifer from 157 feet to 172 feet below ground surface
[bgs). Well F-MW43S was screened ne~I the top of the shallow
aquifer from 118 feet to 123 feet bgs. Figure 6 shows the location
of the nested well pair.)
-------
+ 0 200
[=::J
NORTH Feet
LEGEND
\--
Railroad Siding
\
~ ,.,.-
~ '~ofSol
\ GIs Swwy
r--..--------..-----.,
. H2O .
\ R19 i
\ R18 i
. .
. .
, ,
. .
\ R16 i
. .
. .
, ,
. .
. .
, ,
. .
. .
, ,
. .
. .
, ,
. .
. i
, .
. .
. ,
, .
. .
. I
, .
. .
. I
, .
. .
. I
, .
~ \
\ .
. R6 .
, ,
. .
. .
. , ,
. .
. .
, ,
. .
. .
, I
. .
. .
\ 1
. .
. .
, ,
. .
. .
, ,
. .
. .
\ \
. .
--..- ----I
Typical Revetment Probe Locations
!t
E
;-
't;
~
CLEAN
COUPREHEHSIVE ~
TERM ENY1RONM&fTAL
ACTDI NAVY
Figure 5
Boundaries of Soil Vapor Survey In Old Barricaded Railroad
Sidings at Site 5
CTO 0038
SUBASE. Bangor
WashingIDn
-------
?
200
I
.~
NORTH Feet
LEGEND
$/ Wa/8r Table 8evalion
F-IIWe
. Mom:mg Well Locatianf NIIIIb8r
" Generaized Groc.ndwater Row Indion
CLEAN
COMPRSiENSIVE LONG-
TERM ENVRONMENTAl
ACTK>N NAVY
Agure6
location of Monftorlng Wells and Shallow AquIfer Water
Table 8evatlon Contour Map
MaciIied flam Hall CnMser 1 SI82
CTO 0038
SUBASE. Bangor
Washington
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Na\l)' CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
cro 0038
Record of Decision
Date: (J9 /22/93
Page 16
Findings:
Surface water runoff aad sediments. No dissolved metals detected in surface
water samples exceeded EPA maximum cont3.minant levels (MCLs).
Concentrations of beryllium detected in stormwater sediments exceeded
background surface soil concentrations but are within the range of subsurface soil
concentrations.
Soil vapor surveys. All three $Oil vapor surveys indicated the presence of mercury
in soil vapors. The two screening-level surveys were used as a predictive tool for
subsequent sampling. The laboratory results from the long-term survey were used
to analyze risks at the site, which were determined to be within the EP A's
acceptable risk range.
Soils suneys. Mercmy was detected in all test pit samples between 0.018 and
0.097 mg/Icg. The data indicated that the concentrations of merauy detected at
Site 5 are at or slightly above natural background concentrations. Mercury data
from Site 5 are compared with background concentrations in Table 1.
Table 1 ,."
Comparison of Observed Mercury LeYeIs at Site 5 to
Natural Background Concentrations at SUBASE, Bangor
~~~~
Surface soil
Subsurface soil
0.08
om
oms
0,(197
To summarize the results of the remedial investigation, mercury was not selected as a
chemical of potential concern (COPC) for Site 5 soil or water because the maximUm "
concentrations in the site soil were below the risk-based screening concentration (RBSC)
and because mercury was not detected in water. (Se~on 7.0 discusses RBSC screening.)
Even if mercury were present in water at half the detection limits. the concentrations
would not exceed the RBSC. Because mercury was detected in soil vapor samples taken
at a depth of 10 to 15 feet below ground surface at Site 5. there is the potential for
mercury to migrate through the soil profile and volatilize into the ambient air. However,
no source of mercury was found during the site investigation (URS 1992a). Therefore.
the lateral and vertical extent of contamin8tion and site-specific fate and transpon
cannot be addressed.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ere 0038
Record of Decision
Date: 09112193
Pag~ 17
7.0 SUMMARY OF SITE RISKS
The results of soil analyses taken at the FML site were compared with background
levels, State of Washington Model Toxies Control Act (MTCA) Method B values, and
EPA Region 10 RBSCs to determine whether the detected concentrations of chemica1S
exceeded screening concentrations. No chemicals of concern exceeded these screening
levels at this site; therefore, a human health risk assessment was not performed.
The results of mercury analysis of s3.IJ1ples from Site 5 were compared with SUBASE,
Bangor, naturally occurring levels and EP A Region 10 RBSCs to determine whether the
detected concentrations of mercury exceeded screening concentrations. No
concentrations of mercury in soil exceeded EPA Region 10 RBSCs. No mercury was
detected in the groundwater or surface water. The risk assessment developed for a
hypothetical future residence at Site 5 indicated that indoor air concentrations of
mercury would be below the level of concern and would not present an unacceptable
health risk.
The following were considered as potential pathways of migration for possible
contamination at Site 5: movement of mercury vapors through the soil into the ambient
air, migration of residual mercury in surface water runoff and groundwater movement,
uptake of residual mercury in vegetation at the site, and bioaccumulation of mercury at
increasingly higher levels of the food chain.
7.1
HUMAN REALm RISK ASSESSMENf
7.1.1 FML Site
.
Background Concentrations
Table 2 compares soil metals data from the FML area with naturally occurring
concentrations. The evaluation shows that the levels of arsenic, beryllium, chromium,
lead, and nickel detected in the soils were at or below naturally occurring concentrations
in soils at SUBASE, Bangor, thus eliminating these elements as COPCs.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N6247~89-D-9295
ero 0038
Record of Decision
Date: fY} /12/93
Page 18
Table 2
Comparison of Observed FML SOU Metals
Concentrations to Naturally Occurring Concentrations
Arsenic 3.57 2.52 0.62 1.6
Beryllium 0.27 1.03 0.57 1
Chromium 27 33 13 25.8
Lead 19 5 0.85 3.6
Mercury 0.08 0.05 0.04 i~~~!~~~~t?~lmN~[t~f
Nickel 55 91 38.5 51.7
Note: Shading under mercury indicates maximum concentration exceeds background.
.
RBSC Comparisons
The maximum concentration of mercury detected in the soil at the FML site is below the
EPA Region 10 RBSC and the State of Washington MTCA Method B concentration
(Table 3).
.
Results
Based on this evaluation, no COPCS were identified at the FML site.
7.1.2 Site 5
According to the au 5 work plan (BVWST 1991) and the CSR, Volume I (Hart
Crowser 1989), historical data identified mercury as the principal waste constituent of
concern at Site 5. This concern was supponed by th~ detection of mercury vapor during
the site investigation (URS 1992a). This investigation served as a screening tool,
indicating the need for longer term mercury vapor testing to produce laboratory-quality
results. . Laboratory-quantified mercury vapor concentrations were obtained from sorbent
tubes containing Hydrar used for the long-term survey (URS 1992b).
~
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474.89-D-929S
ero 0038
Record o( Decision
Dale: 09/22/93
Page 19
Table 3
Comparison or Observed Soli Concentrations with EPA Region 10 RBSCs nnd
Washington MTCA Method B Proposed Cleanup Levels.
No
NA = not available
.Risk.based calculation based on soil ingestion is not appropriate for elemenlal mercury since inhalation exposure is o( grealer concern (or Ihis melal.
The RBSC for mercury was derived assuming 0.27 m' air/kg body weight/day (EPA 1991, Appendix III) and 50 Ilg particulales/m' air (ambient air
quality standard for PMI0).
"The reference dose (RID) (or inorganic mercury was used because elen1ental mercury is the volatile (orm. This RID was calculated from a prev;,>usly
listed chronic reference concentration (EPA 1992a). However, this RID (or inorganic mercury is currenlly under review hy Ihe EPA.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89.D-9295
ero 0038
Record of Decision
Date: 09/12/93
Page 20
As stated in Section 5.0, the risk assessment for noncancer and cancer risks at au 5
shows that Site 5 presents no significant current or potential risks to human health or the
environment.
A statistical analysis was conducted on data from the matrices sampled at Site 5. Tbe
mean analytical values, the maximum observed values, and the 95-percent upper
confidence limit values are shown in Table 4.
Table 4
Statistical Results of Mercury (Og) in M~trices Sampled at Site 5
Hg, vapor 61 mglm' NA 0.173 >0.999 0.248
(March)
Hg, vapor 34 mglm' NA 0.336 >0.999 0.467
(JUDe)
Hg, vapor (8 hours) 9 mg/~ NA 0.002 0.004 0.003.
Hg, vapor (1 hour) 9 mgl~ N~ 0.003 0.010 0.005
Surface Hg, total 5 p.gIL 1.1
water Hg, dissolved 5 p.g!L
Groundwater Hg, total 2 p.gIL 11.0
N = number of samples
UCL95 = upper 95-percent confidence limit
NA = not available
.Mercury was not detected in any samples; results used in risIc L~t were less than the detection limit
'Exposure point values were used to estimate risk.
Note:. Shaded values indicate the values used forcomparisoD with the SUBASE, Bangor, naturally occurring
levels and EPA Region 10 RBSCs.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Nortbwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09/12/93
Page 21
.
Background Comparisons
Naturally occurring concentrations of metals in surface and subsurface soil were
calculated according to the methodology provided by Ecology (1992). The data indicate
that the concentrations of mercury detected in the soil at Site 5 are at or slightly above
naturally occurring concentrations. Table 5 compares mercury data from Site 5 with
naturally occurring concentrations.
; Table S
Comparison of Observed Mercury Levels at Site S to
Naturally Occurring Concentrations at SUBASE, Bangor
1___,-
I Swfa", soil ::3 O.os 0.075 I
. Subourl"oce soil _: 0.08 OJJ97:
.
RBSC Comparisons
As shown in Table 6, mercury concentrations in soil were well below the EPA Region 10
RBSC, corresponding to a hazard quotient (HQ) of 0.1. The hazard quotient is a
quantity resulting from the comparison of an observed concentration of a chemical with
the established reference dose. If the results are greater than 1.0, exposure to that
chemical is considered to be of potential concern.
Mercury was not detected in any samples of groundwater or surface water. Even if it is
assumed that mercury is present in these samples at one-half the detection limit, these
concentrations are substantially below the RBSCs for mercury in these media. The
concentrations presented in Table 6 are only estimates of the levels of mercury based on
the contract-required quantitation limit (CRQL). CRQLs are levels down to which
laboratory procedures are required to detect specific chemicals.
EPA does not provide RBSCs for air (EPA 1991). Consequently, comparison of mercury
concentrations in site air with RBSCs was not possible.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D.9295
era 0038
Record of Decision
Dale: 09/22/93
Page 22
Table 6
Comparison of Results of Mercury Sampling
at Site 5 to EPA Region 10 RBSCs
.....
Soil Ingestion 0.1 8.2 mg/kg Surface soil No
SubsurCace soil No
Water 3.00E-04 Oral 0.1 1.10 pg/L Surface water No.
1.0 11.0 pg/L Groundwater No"
SoU 3.00E.04 mg/mJ Inhalation Not Not Soil gas Not
gas applicable applicable applicable
..",.....",". .".",'".".. "."."
. . . .....".. ....... ..
~I;!I!I~II'-~?!{
...
'Taken from EPA 1992a. Ingestion and inhalation toxicity criteria for mercury have been withdrawn Crom the Integrated Risk InCormalion System (IRIS).
bCalculated according to EPA 1991.
"All total mercury results in groundwater and lIurrace water were nondetects. The maximum concentrations listed Cor these samples are hair the contract-
required quantitation limit (CRQL) of the laboratory method used. Levels below CRQL are "nondetects" but not necessarily zero.
-------
'; , ,;:}. ~~-~.'
"'...
\'!Wi:'lit11j1t
.~7:\:!.":. ~
I.}/\',~~!:.;;]~'~ "
~ i,.oi;1.'~,'.;r;v~ l,
"'. . I
, .
.'.~:. ,<~:
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Cootrad
Engineering Field Activity, Northwest
COD tract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: 09 /Z2./93
Pag:23
.
Results
Only mercury concentrations in tbe air were evaluated in tbe risk assessment; mercury
was not selected as a cbemical of potential concern for Site 5 soil or water. No
unacceptable risks were found for mercury at Site 5.
7.2
RISK CHARACl'ERIZATlON
7.2.1 FML Site
Arsenic, beryllium, chromium, lead, and nickel concentrations are at or below naturally
occurring concentrations in soils at SUBASE, Bangor. Mercury concentrations are below
EPA Region 10 RBSCs. Mercury is also below tbe State of Washington MTCA Method
B value. Furthermore, under current conditions, tbe aspbalt surface in tbe vicinity of the
child-care center minimi7es direct exposure to tbe underlying soil, reducing potential risk.
7.2.2 Site 5
Mercury levels in tbe soil samples are below SUBASE, Bangor, naturally occurring levels
and EPA Region 10 RBSC levels. Mercury levels in soils are also below the State of
Washington MTCA Method B levels.. Using an estimated indoor air concentration
(lAC) of mercury, noncancer risks were calculated for a bypothetical future resident who
migbt be exposed to mercury vapors. This calculation requires comparing the estimated
lAC of mercury with an acceptable, bealth-protective level. A reference concentration
(RfC) of 3 x lQ-4 mg/m3 has been used to represent a safe exposure level. However, the
EP A bas withdrawn the RfC for mercury from its IRIS cbemical toxicity database (U .5.
EPA 1992a) pending review by an EPA work group. For this evaluation, EPA Region
10 requested that the withdrawn RfC, whicb is still listed in the Health Effects
Assessment Summary Tables (U.S. EPA 1992b), be used as an interim toxicity value until
an updated RfC becomes available.
A predictive model was developed to estimate tbe concentration of mercury in tbe
indoor air of a hypotbetical residence built on Site 5. This model estimated tbe flux, or
transport, of mercury vapor from the soil through the foundation wall and into the
ambient air of the residence. The model used for this task was tbe Hensley and
Schofield model, whicb was based on a radon soil gas transport model. Dividing the
estimated lAC for mercury (URS 1992b) with the RfC yields an HQ. Thus, 8 x 10-7
mg/m3 divided by 3 x lo..c mg/m3 is equal to an HQ of 3 x 10-3, a value below 1.0, the
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
crOOO38
Record of Decision
Date: 09/22/93
Page 24
,~
standard level of concern. If a house were built on Site 5, mercury would not present an
unacceptable health risk.
In addition, because occupational exposures are typically less than residential exposures
(due primarily to reduced time spent on site), inhalation of mercury vapors by workers at
Site 5 would not pose an unacceptable risk. The maximum concentrations of mercury
vapor in air yield acceptable risks for noncancer effectS for both future residential and
occupational exposure.
7.2.3 Uncertainty Analysis
The general trend of the risk characterization performed at Site 5 and the FML site was
conservative. An overestimation of risk is expected to result.
.
Analytical Results
The results for Site 5 water data are derived from samples reporting undetected
concentrations at the CRQL In this case, the mean, maximum, and 95-percent upper
confidence limit value are equal. This situation is acceptable because the CRQLs are
below screening concentrations.
Most analytical methods produce results with an accuracy range of 10 to 20 percent
(McKown et al. 1984).
.
Screening Concentrations
RBSOi were compared to the maximum observed ievels of mercury found at these sites.
Because of the limited sampling and analysis activities at Site 5 and the FML site and '
the potential for error propagated during field investigations, the maximum detected
value for any chemical in a solitary sample requires Careful interpretation. The screening
method is conservative, with a potential to overestimate risk.
. ,
A number of uncertainties are inherent in the assumptions and calculations related to
indoor mercury concentrations. First, it is conservative to assume that a residence will
be built on Site 5. It is not anticipated that the site will change to include residential
use. In addition, the site is composed of building fill 'materials, and excavation of the
area and construction of a residence on this site is highly unlikely. It is also conservative
to assume that the building foundation and compacted soils surrounding the building will
-------
..
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
era 0038
Record of Decision
Date: (1)/22/93
Page 25
not attenuate the flux of mercury from the soils intO the indoor air. The RfC for inhaled
mercury is somewhat uncertain because the EP A has withdrawn it from the IRIS
cbemical toxicity database (U.S. EPA 1992a). The RfC used in this risk assessment is
based on a no-effects level observed in several long-term human studies and includes an
uncertainty, or safety, factor of 30. Based on tbe number of conservative assumptions
included in our analysis, it is.highly unlikely tbat indoor air concentrations of mercury
would exceed bealth-protective levels.
7.3
ECOLOGICAL RISK ASSESSMENT
,
7.3.1 FML Site
The area of tbe original FML is a paved parking lot; no ecological risk is posed by this
site. No ecological evaluation was conducted at this site.
7.3.2 Site 5
.
Site Species
The forest in the vicinity of Site 5 provides good habitat for a variety of animal species,
including deer, and probably is a refuge for animals that are transient foragers in the
rubble area.
No threatened or endangered species were observed at Site 5. Bald eagles, which are
protected under the Bald Eagle Protection Act of 1940 and the Endangered Species Act
of 1973, may perch on trees in the surrounding forest No endangered or threatened
plant species are known to be found at SUBASE, Bangor.
.
Exposure Pathways and Receptors
Having no known biological function, mercury is toxic in an inorganic form, but has
greater toxicity after transformation into organic forms such as methyl mercury. Mercury
can accumulate at higher levels in the food chain, eventually posing greater
environmental risks to top-level predators than to organisms at the base of the food
chain.
-------
SUBASE, BANGOR, OPERABLE UNIT 5
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
ero 0038
Record of Decision
Date: C1}/Zl/93
Page 26
")
The following pathways and receptors were selected for evaluation of mercury at Site 5:
.
Root uptake from soils by weedy herbaceous plants
.
Ingestion of vegetation by a herbivorous small mammal (Townsend's vole)
.
Incidental ingestion of soils by a small burrowing mammal (Townsend's
vole)
.
,
Predatory consumption 'of small mammals by coyotes
Townsend's voles and coyotes are common at SUBASE, Bangor.
.
Summary and Conclusions
HQs were determined for receptor species: voles and coyotes. HQs greater than 1.0
indicate a potential stress on exposed organisms. There are no risks greater than 1.0 to
voles or coyotes from exposure to mercury in soil at Site 5. Risks to voles and coyotes
through ingestion of soil, water, vegetation, and prey were not above 1.0 for either ionic
or total mercury. Risk for exposure to mercwy vapor inhalation by burrowing animals
was below 1.0 when a toxicity reference value for humans was used.
7.4
FUI'URE RISK SCENARIOS
It was assumed in the risk characterization that present data are representative of data
that would be coJIected in the future. It is anticipated that the soil vapor concentrations
of merClli']' would be reduced over time through volatilization. Because no source area
for mercury has been firmly identified in subsurface soils, no additional significant.
release of mercury is expected.
8.0 THE SELECI'ED REMEDY
The selected remedial action at OU 5 is the no-action alternative. The risk assessment
for noncancer and cancer risks at au 5 shows that the FML site and Site 5 present no
significant current or potential threats to human health or the environment and do not
warrant further action.
-------
i
SUBASE, BANGOR, OPERABLE UNIT 5
U.s. Navy CLEAN Contract
Engineering Field Adivity, Northwest
Contract No. N62474-89~D-9295
ero 0038
Record of Decision
Date: 09/12/93
Page 27
-
Concentrations of all metals found in the FML site soils, including mercury, were at or
below naturally occurring concentrations in soils at SUBASE, Bangor. Soil
concentrations of metals were also below the State of Washington's acceptable
concentrations for those metals with pubJished values of acceptable concentrations. In
addition, the asphalt surface covering the original FML area minimi7es direCt exposure
to the underlying soil, reducing any potential risk. On the basis of these findings, no
compounds were seleCted for risk evaluation at the FML.
Risks for mercury in any environmental medium at Site 5 were determined to be within
the National Contingency Plan's acceptable risk range.
Based on the information currently available, the Navy, EP A, and Ecology conclude that
the existing conditions at the two sites are protective of human health and the
environment, and a no-aCtion decision is warranted.
9.0 REFERENCES
B&V Waste Science and Technology Corporation (BVWST). 1991. Final Work Plan for
Operable Unit 5, Naval Submarine Base, Bangor.
Hart Crowser, Inc. 1989. Current Situation Report, Sites 4 D, E, F, 5, 6, 11, 12, 24, and
25, SUBASE, Bangor. Prepared for Naval Facilities Engineering Command,
Silverdale, Washington. May 1989.
Hensley, P J., and AN. Schofield. 1990. "An Approximate Solution to Contaminant
Transport by Parabolic Isochromes." Geotechn.ique 40(2):285-291.
McKown, G.L, R. Schalla, and CJ. English. 1984. "Effects of Uncenainties of Data
Collection on Risk Assessment." MtllUlgement of Uncontrolled Hazardous Waste
Sites. Proceedings of the 5th National Conference, Hazardous Materials Control
Research Institute, Silver Springs, Maryland.
"
Naval Energy and Environmental Support Activity (NEESA). 1983. Initial Assessment
Study of Naval Submarine Base Bangor, Bremerton, Washington. NEESA 13-004.
June 1983.
-------
SUBASE, BANGOR, OPERABLE UNIT 5 .
U.S. Navy CLEAN Contract
Engineering Field Activity, Northwest
Contract No. N62474-89-D-9295
era 0038
Record of Decision
Date: 09/22/93
Page 28
:.
..
Spencer, R.R. 1983. Navy data, as cited by Hart Crowser in Curre17.l Situation Report,
Sites c: D, E, F, 5, 6, 11, 12, 24, and 25, SUBASE, Bangor. Prepared for Naval
Facilities Engineering Command, Silverdale. Washington. May 1989.
URS Consultants, Inc. (URS). 1993. The ProposedP/an for Operable Unit 5. February
1993.
-. 1992a. Site Investigation Report, Operable Unit 5, SUBASE Bangor. Prepared' for
Naval Facilities Engineering Cpmmand, Silverdale, Washington. (erO 0069).
September 1992. '
-. 1992b. Remedial Investigation/Feasibility Study, Operable Unit 5, SUBASE
Bangor. Prepared for Naval Facilities Engineering Command, Silverdale,
Washington. (erO 0038). December 1992.
United States Environmental Protection Agency (U.S. EPA). 1992a. Integrated Risk
Information System (IRIS) database. Accessed through Cbemica1lnformation
Systems.
-. 1992b. Hea1Jh Effects Assessme17J Summary Tables (BEAST). Annual update.
Office of Research and Development, Office of Health and Environmental
Assessment, Environmental Criteria and Assessment Office, Cincinnati, Ohio.
1
I'
I
I
[
Ii
I:
I!
-. 1991. EPA Region 10 Supplemental Risk Assessme17J Guidance for Superfund.
Region 10, Seattle, Washington. August 1991.
..
------- |