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PUBLIC HEALTH ASSESSMENT

NAVAL AIR STATION WHIDBEY ISLAND (AULT FIELD AND SEAPLANE BASE)
OAK HARBOR, ISLAND COUNTY, WASHINGTON


ENVIRONMENTAL CONTAMINATION AND OTHER HAZARDS

A. Introduction

The contaminants discussed in subsequent sections of this public health assessment are evaluated todetermine whether exposure has occurred, and if so, whether that exposure has public healthsignificance. ATSDR selects and discusses contaminants using the following information:

  • concentrations of contaminants on and off site;

  • the quality of the field and laboratory data and sample design;

  • comparison of on- and off-site concentrations with comparison values for noncancer and cancer endpoints; and

  • community health concerns.

The listing of a contaminant in the following tables does not mean that it will cause adverse healtheffects if exposure occurs at the specified concentrations. Rather, the listing of a contaminantindicates that it will be discussed further in this public health assessment. The potential for adversehealth effects resulting from exposure to contaminants of concern is discussed in the Public HealthImplications section of this document. When a contaminant exceeds comparison values in onemedium, it will be discussed or listed in the tables for all media. Most of the comparison values inthis document are based on adult ingestion rates and body weights, since most of the areas underinvestigation are visited by adults. Comparison values for children are lower than those for adults. ATSDR uses lower comparison values when children at a site could be exposed to contaminants in aspecific media; residential areas and elementary schools are examples of sites where lowercomparison values may be used.

Comparison values for ATSDR public health assessments are contaminant concentrations in specificmedia that are used to select contaminants for further evaluation. ATSDR and other agenciesdeveloped the values to provide guidelines for estimating the media concentrations of a contaminantthat are unlikely to cause adverse health effects, given a standard daily ingestion rate and standardbody weight.

These abbreviations are used in the following tables:
CREG Cancer Risk Evaluation Guide (promulgating agency: ATSDR). CREGs are estimated contaminant concentrations based on a one excess cancer in a million persons exposed over a lifetime (70 years). CREGs are calculated from EPA's cancer slope factors.
EMEG Environmental Media Evaluation Guide (ATSDR). EMEGs are values used to select chemical contaminants of potential health concern. EMEG values are calculated by ATSDR using conservative exposure assumptions that would protect the most sensitive segment of the population.
RMEG Reference Dose-based Media Evaluation Guide calculated using a Reference Dose (RfD) (definition below). RMEGs are values used to select chemical contaminants of potential health concern.
LTHA Lifetime Health Advisory (EPA). LTHAs represent contaminant concentrations that EPA deems protective of public health over a lifetime (70 years) at an exposure rate of 2 liters of water per day. LTHAs are not enforceable through EPA regulations.
MCL Maximum Contaminant Level (EPA). MCLs represent contaminant concentrations that EPA deems protective of public health over a lifetime (70 years) at an exposure rate of 2 liters of water per day. While MCLs are regulatory concentrations, Proposed Maximum Contaminant Level Goal (PMCLGs) and Maximum Contaminant Level Goal (MCLGs) are not.
mg/kg milligrams per kilogram, equivalent to ppm (see below)
PMCLG Proposed Maximum Contaminant Level Goal (EPA). Proposed Maximum Contaminant Level Goals (PMCLGs) are MCLGs that are being proposed and are not enforceable.
ppb parts per billion
ppm parts per million
RfD Reference Dose (EPA). EPA's Reference Dose (RfD) and Reference Concentration (RfC) are estimates of the daily exposure to a contaminant that is unlikely to cause adverse health effects.
Class A EPA cancer classification. Known human carcinogen
Class B EPA cancer classification. Probable human carcinogen

Background Concentrations

Background levels in local soil and water may be greatly influenced by high levels of chemicalsfrom native mineral deposits or other natural sources. Background levels could be anthropogenic(e.g., gravel for a road or parking lot) substances in the environment due to human-made, non-sitesources. If contaminants detected on site are below background concentrations, but exceedapplicable comparison values, ATSDR will list them in the data tables to follow and evaluatewhether exposure to them is of public health concern.

B. On-Site Contamination

RI reports and other investigation reports are written throughout the IRP process, and mediamonitoring and sample analyses in each phase generated new data for each site under investigation. Sometimes, the data used in the discussions that follow came from draft copies of IRP reports. Dataqualifiers that were in the IRP reports were carried to the tables below. Where the IRP reports notedthe data had not received quality assurance/quality control review, the appropriate data or tables arefootnoted with statements to that effect.

The public comment release of the NAS Whidbey Public Health Assessment included data fromdocuments through 1992. For this release, ATSDR reviewed the latest RI reports through June1993. However, the data tables in this section were not amended since the data did not changeconclusions and recommendations and the tables serve only as an overview of the contaminatedareas. Appropriate changes were made in the conclusions and recommendations due to proposed remedial actions.

Areas under investigation are grouped into Operable Units (OU), OU1 to OU5 and the HazardousWaste Evaluation Study (HWES). During the Current Situation Report (CSR), HWES, andRemedial Investigations (RI) of the OUs, soil, sediment, surface water, and groundwater analysesincluded metals and cyanide, VOCs, semivolatile organic compounds (SVOCs), pesticides,polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and pesticides. During the RI for OU3, fish and shellfish will be sampled and tested. Shellfish will be sampledduring RI field work for OU4 (14).

Operable Unit 1

OU1 consists of Area 5, the Highway 20/Hoffman Road Landfill and Area 6, Landfill (Appendix A,Figure 3). These areas are grouped because both served as main facility landfills, are close to eachother, and are above the same aquifer recharge area. The types of contaminants detected during the1991 and 1992 RI investigations at OU1 are shown in Table 9.

Soil, sediment, surface water, and groundwater analyses included metals and cyanide, VOCs,SVOCs, pesticides, PCBs, organophosphorus pesticides, and chlorinated herbicides. The Navysampled soil gas, ambient air, and particulates at Area 6.

At Area 5, VOCs were detected in surface water and shallow groundwater, SVOCs in subsurfacesoil, pesticides in sediment, and inorganics in sediment, surface soil, subsurface soil, surface water,and shallow groundwater. At Area 6, VOCs were detected in soil gas, air, surface soil, subsurfacesoil, surface water, and shallow, intermediate, and deep groundwater. SVOCs were detected in air,surface sediment, and shallow groundwater, and pesticides in sediment and shallow and deepgroundwater. Heavy metals were detected in air, surface sediment, surface soil, subsurface soil,surface water, and shallow, intermediate, and deep groundwater.

Table 9.

Summary of Detected Compounds in Operable Unit 1 (6)
Media Class of Compound
VOC SVOC Pesticides PCB PAH Metals
Soil Gas • n/a n/a n/a n/a n/a
Air • • n/a n/a n/a •
Sediment • • • o o •
Surface Soil • • • o • •
Subsurface Soil • • o o o •
Surface Water • o o o o •
Groundwater • o • o • •
• detected
o not detected
n/a not analyzed

OU1 Waste

At Area 6, the Navy tested liquid waste from the former hazardous waste storage area in March1981 as part of the Initial Assessment Study (IAS). The former hazardous waste storage area is inArea 6, where the groundwater plume is suspected to originate. The liquid waste contained barium(690 parts per billion [ppb]), cadmium (1400 ppb), total chromium (11,100 ppb), chromium VI (<5 ppb), lead (9200 ppb), mercury (2 ppb), nickel (430 ppb), zinc (2700 ppb), and phenol (750,000ppb).

OU1 Surface Soil

ATSDR considers soil taken from a depth equal to or less than 3 inches (<3") as surface soil. People are most likely to be exposed to soil from that layer by ingestion or dermal contact. Table 10 lists the contaminant concentrations in on-site surface soil. Additional OU1 surface soil samples were taken to a depth of 2 centimeters (cm) during the Interim Action (27) and RI Phase I (6).

During the RI, three surface soil samples were collected during the installation of three wells at Area5. Detected contaminants were below comparison values for soil. At Area 6, 39 surface soilsamples were analyzed. The Navy always found VOC contamination within 500 feet of the formerhazardous waste storage area (6). Cyanide and 15 of 18 metals were detected, generally near thehazardous waste storage area and the Area 6 landfill. The maximum concentration for berylliumcame from a single sample on Area 6 near the hazardous waste storage area (Table 10) (10). ATSDR has not developed ingestion and dermal contact comparison values for concentrations oflead, nickel, and vanadium that are detected in soil or sediment.

Table 10.

Contaminant Concentrations at Operable Unit 1
OU, Area Contaminant Min&Max Level for Each Contaminant Reference
AII-6/90, RI-7/91
Comparison Value, mg/kg Source

On-Site Surface Soil, mg/kg

OU1, 5 Lead 4.5-31.6J AII, RI/FS None
Nickel 18J-36 RI/FS None
Vanadium 28.1 RI/FS None
OU1, 6 Beryllium 0.3-378.7 RI/FS 0.16 CREG
Lead 3.1-63 AII, RI/FS None
Carc. PAH 0.040-0.22 RI/FS 0.12 CREG (BaP)

On-Site Sediment, mg/kg

OU1, 5 Lead 4.5-8.3 RI/FS None
Nickel 18.2-148 RI/FS None
Vanadium 16.9-53.8 RI/FS None
OU1, 6 Heptachlor epoxide ND-0.42 RI/FS 0.16 CREG
Aldrin ND-0.077 RI/FS 0.041 CREG
Lead 1.6BJ-19.7J RI/FS None
Nickel 31J-89.1J RI/FS None
Vanadium 15.7-45.8 RI/FS None

Notes:
J - Contaminant was positively identified; estimated concentration
B - Metals: Contaminant detected at less than contract required detection limit, but greater than the instrument detection limit
B - Organics: Contaminant detected in associated laboratory blank
ND - Not detected

Carc. PAH (carcinogenic PAHs) - benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, ideno(1,2,3-cd)pyrene
BaP - Benzo(a)pyrene, a carcinogenic PAH

Sediment samples for Area 5 were taken from the wetland area to the west.

OU1 Sediment

There are no wetlands or surface water within Area 5, so sediment samples were taken from a wetland 1000 feet west of the area. Eleven sediment samples were collected and analyzed. Sediment from the eastern edge of the wetland close to the border of NAS contained metals and a pesticide below comparison values (28).

At Area 6, samples were taken from the intermittent stream within the area at five stations during theInterim Action and during the RI. Samples of surface sediment were analyzed for VOCs andinorganic compounds. At selected locations, samples were analyzed for SVOCs, pesticides, PCBs,organophosphorus pesticides, and chlorinated herbicides (28). Metals and pesticides were detectedin sediment at Area 6 (Table 10) in samples taken from the ephemeral (intermittent) stream thatflows north toward Area 5. Most of the pesticides detected were from a single station in thenorthwest part of Area 6 (28). Lead, nickel, and vanadium in sediment have no comparison valuesfor ingestion or dermal contact.

OU1 Subsurface Soil

ATSDR considers soil from depths greater than 3 inches (>3") as subsurface soil. Subsurface soilsamples were collected when monitoring wells were drilled and from soil borings. Contaminantsfound in subsurface soil samples do not necessarily reflect surface soil contamination.

At OU1 Area 6, 35 samples were collected for chemical analysis. Soil samples were collected at 5-foot intervals from bore holes to a depth of 50 feet and in screen zone for all wells. VOCs weregenerally found in subsurface soils near the former hazardous waste storage area (6). Low levels ofchloroform (0.004-0.008 mg/kg) were detected down to 201 feet and were below comparisonvalues.

Cadmium (472 mg/kg) was detected above comparison values at a depth of 20 feet in a soil samplefrom a bore hole near the hazardous waste storage area (10). Cadmium was not detected at thatlevel in any other sample.

OU1 Soil Gas

A total of 223 soil gas samples were collected from January to July 1991. The soil gas sampleswere used to position monitoring well, soil boring, and surface soil sampling points. The highest soilgas concentrations were in Area 6 near the former hazardous waste storage area and northwest of thehazardous waste storage area (trichloroethylene-60,000 ppb, 1,1-dichloroethane-97,000 ppb, 1,1-dichloroethene-5000 ppb). Other locations of high concentrations of VOCs were to the northeastand north of the hazardous waste storage area (benzene-25,000 ppb, tetrachloroethylene-1700 ppb). The Navy detected soil gas northwest of the western boundary of Area 6 and NAS within 800 feetfrom the hazardous waste storage area (benzene-630 ppb, tetrachloroethylene-690 ppb, 1,1-dichloroethane-15,000 ppb, 1,1-dichloroethene-450 ppb) (6). Currently, no structures are located ator near Area 5 or Area 6, therefore the only potential is if such structures are built. Since OU1consist of landfills, it is unlikely that it will be developed for future residential use and an industrialscenario may also be unlikely. The Code of Federal Regulations, Volume 40, Part 258 ("EPACriteria for Municipal Solid Waste Landfills (MSWLFs)"), Subpart F ("Closure and Post ClosureCare"), paragraph 258.60 (i) (1) and (2) state that "Following closure of all MSWLF units, theowner or operator must record a notation on the deed to the landfill facility property...The notationof the deed must in perpetuity notify any potential purchasers of the property that: (i) the land hasbeen used as a landfill facility; and (ii) its use is restricted under paragraph 258.61 (c) (3)."Paragraph 258.61 (c) (3) states that "Post closure use of the property shall not disturb the integrityof the final cover, liner(s), or any other components of the contaminant system, or the functioningmonitoring system."

OU1 Surface Water

Since there are no comparison values for surface water, drinking water comparison values wereused. There is no surface water in Area 5. A wetland to the west of the Area 5 was sampled. Samples from three points on the northeastern, eastern, and southern edge of the wetland detectedVOCs and metals. The maximum dichloroethene concentration is in the northeastern sample and isabove comparison values (Table 11). The Navy detected lead (4-5 ppb) in surface water nearArea 5 during the Current Situation Report (2) in 1987. Five metals were above comparison values. ATSDR could not determine any trends from the few sample points. Unspeciated chromium islisted, because it was detected above comparison values in groundwater.

Table 11.

Contaminant Concentrations at Operable Unit 1
OU, Area Contaminant Min&Max Level for Each Contaminant Reference
AII-6/90, RI-7/91
Comparison Value, ppb Source

On-Site Surface Water, ppb

OU1, 5 1,1-Dichloroethene ND-4.9 ppb RI/FS 0.058 CREG
OU1, 6 Antimony ND-39.2 ppb RI/FS 3 LTHA
Arsenic ND-15.2 ppb RI/FS 11 RMEG
Total chromium ND-83.1 ppb RI/FS 100 LTHA
Lead ND-33.5 ppb RI/FS None
Nickel ND-223 ppb RI/FS 100 LTHA
Vanadium ND-205 ppb RI/FS 20 LTHA

On-Site Groundwater - Monitoring wells, ppb

OU1, 5
Shallow
Aquifer
1,1-Dichloroethene ND-0.46 RI/FS 0.058 CREG
Arsenic ND-310B IA, RI 11 RMEG
Total Chromium ND-36J IA, RI 100 LTHA
Lead ND-29.9 IA, RI None
Manganese ND-35,147 RI 3500 RMEG
Nickel ND-120 IA, RI 100 LTHA
Nitrate 1100-13,000 IAS, IAS 10,000 MCLG
Vanadium ND-246 RI 20 LTHA
Zinc ND-2410 IA, RI 2100 LTHA

OU1 Area 6 unfiltered surface water samples were taken from a wetland in the central part of thearea and from an ephemeral stream that flows from the wetland in Area 6, north to the wetland northof Ault Field Road. The maximum concentrations for arsenic, chromium, lead, and nickel werefrom a stream sample in the northeast corner of Area 6.

OU1 Groundwater - Monitoring Wells

Area 5

The Navy has not identified any groundwater contaminant plumes in Area 5. No contaminants were confirmed in Area 5 groundwater from three existing monitoring wells installed during the Accelerated Initial Investigation (29). During RI Phase I, the Navy sampled shallow aquifer groundwater at three existing wells once during the wet season and once during the dry season. They detected arsenic, chromium, manganese, nickel, vanadium, and zinc above comparison values (Table 11). The concentration of nitrate was above comparison values. VOC concentrations were below comparison values in a monitoring well in the north part of Area 5. No SVOCs, chlorinated pesticides, PCBs, organophosphorus pesticides, or chlorinated herbicides were detected (28). Groundwater under Area 5 appears to flow toward the northwest (6). Twelve groundwater samples were collected during the RI and analyzed for fluoride, nitrate, and sulfate.

Area 6

During RI Phase I at Area 6, the Navy sampled groundwater in 14 new monitoring wells and 15existing wells, and six existing monitoring wells at the Oak Harbor Landfill, once during the wetseason and once during the dry season (28). No SVOCs, pesticides, PCBs, organophosphatepesticides, or chlorinated herbicides were confirmed in groundwater in Area 6 during theAccelerated Initial Investigation (AII) in 1989 and Interim Action (IA) in 1990. Therefore, RIPhase II groundwater monitoring samples were analyzed for only VOCs and inorganics, except twowells near the hazardous waste storage area and two wells in southeastern Area 6, which were testedfor VOCs, inorganics, SVOCs, pesticides, PCBs, organophosphate pesticides, and chlorinated herbicides (28).

Area 6 - Shallow Aquifer. The highest VOC concentrations were in the upper part of the shallowaquifer (Table 12). The maximum concentrations of 1,1,1-trichloroethane, trichloroethylene, 1,1-dichloroethene, total 1,2-dichloroethene, 1,1-dichloroethane, and carbon tetrachloride were fromwells in or near the former hazardous waste storage area (6). Pesticides were detected belowcomparison values in wells in the south part of Area 6 and west central part of Area 6, respectively. The pesticide detections were isolated; the Navy presumedthat they were a result of weed control activities at NAS (28).

Table 12.

Contaminant Concentrations in On-site Groundwater Monitoring Wells, Operable Unit 1, Area 6
CONTAMINANT
(reported as ppb)
Shallow Aquifer Intermediate Aquifer Deep Aquifer Reference Comparison Value, ppb Source
1,1,1-trichloroethane ND-32,000 ND-5J ND-130 AII, IA, RI 200 LTHA
trichloroethylene ND-1800D ND-1.7 ND-167 AII, IA, RI 3.2 CREG
1,1-dichloroethylene ND-1900D ND ND-23 AII, IA, RI 90 EMEG
1,2-dichloroethylene ND-630D ND ND-60J AII, IA, RI 100 LTHA (trans-)
Carbon tetrachloride ND-4400 ND ND AII, IA, RI 0.27 CREG
Methylene chloride ND-26,000E ND-17J ND-12B AII, IA, RI 4.7 CREG
Vinyl chloride ND-53.5 ND ND AII, IA, RI 0.7 EMEG
Antimony 18B ND-71B ND AII, IA, RI/FS 3 LTHA
Arsenic ND-25.2 ND-73 9.0B-70 AII, IA, RI 11 RMEG
Beryllium ND 1.1 ND AII, IA, RI 0.008 CREG
Cadmium ND-9.8 ND ND-7J AII, IA, RI 7 EMEG
Total Chromium ND-1180 ND-6.3BJ ND-20J IAS, CSR, AII, IA, RI 100 LTHA (CrVI)
Lead ND-480 ND-114J 6.5-126J IAS, CSR, AII, IA, RI None
Mercury ND-2.8J ND ND-0.31 AII, IA, RI 2 LTHA
Nickel ND-756BJ ND-9.8BJ ND-18 AII, IA, RI 100 LTHA
Nitrate 30-8400 ND ND IAS, IA 10,000 MCLG
Vanadium ND-148 ND ND-18.2B AII, IA, RI 20 LTHA
Zinc ND-4310J 192-2210J ND-7507 AII, IA, RI 2100 LTHA
J - Contaminant was positively identified; estimated concentration
B - Metals: Contaminant detected at less than contract required detection limit, but greater than the instrument detection limit
B - Organics: Contaminant detected in associated laboratory blank
D - Secondary dilution
ND - Not detected

The Navy has identified five VOC plumes in the shallow aquifer at Area 6; 1,1,1-trichloroethane(TCA), trichloroethylene (TCE), 1,1-dichloroethene, 1,2-dichloroethene, and vinyl chloride (6). The Navy detected the highest concentration of TCA at 32,000 ppb during the Interim Action in1990; they detected TCA during the 1991 RI Phase II at 12,000 ppb in the same well. Theydetected 0.70 ppb TCA in a well at the western edge of the plume and 310 ppb TCA at the southernedge of the plume. The highest concentrations of the TCA, TCE, 1,1-dichloroethene, and1,2-dichloroethene plumes are near the former hazardous waste storage area. The TCA, TCE, and1,1-dichloroethene plumes appear to extend off site to the southwest about 250 feet from the westernborder of Area 6 and NAS and south to the border of Area 6 and Oak Harbor landfills (Appendix A,Figure 15). The 1,2-dichloroethene plume does not extend as far south as the TCA, TCE, and 1,1-dichloroethene plumes. The highest detected concentration of vinyl chloride was in a monitoringwell near the southwestern corner of Area 6, and near the southwestern corner of the current activeNavy landfill operation. The source of vinyl chloride is near the monitoring well or is the activelandfill trenches (6). Vinyl chloride (2.58 ppb) was detected in a monitoring well near the southeastcorner of Area 6, about 300 feet from the Auld Holland Inn.

The vertical extent of contamination in the shallow aquifer is shown by detections of TCA at thebottom of the aquifer of 1150 ppb near the former hazardous waste storage area to 61 ppb at thebottom of the southern edge of the plume. Concentrations of TCA at the southwestern border ofArea 6 have increased from 920 ppb to 3900 ppb from 1989 to 1991. Concentrations at thesoutheastern edge of the plume have increased from 5 to 11 ppb from 1990 to 1991 (6).

Unfiltered samples in the shallow aquifer were analyzed for inorganics. The highest arsenic level isfrom a well in the hazardous waste storage area. Cadmium was generally detected in wells and tothe west of Area 6, and the elevated levels in the RI Phase II were not detected in Phase I (6). Awell at the northeast border of Area 6 and NAS consistently had the highest chromium readings(403, 387, and 1180 ppb). High lead levels were detected during the 1991 RI in the shallow aquiferin the southern part of Area 6 (63.7-121 ppb) and southwest of Area 6 (58.75-87.3 ppb) (6). Themaximum lead level detected during a Navy study in March 1982 came from a well at thesoutheastern edge of Area 6 (29).

During the Initial Investigation at Area 6, the highest manganese levels came from wells in thehazardous waste storage area, but manganese levels were much lower during later sampling and theRI Phase II. Those levels of manganese were also near the active landfill area. Manganese was notdetected in filtered samples from wells where manganese was previously detected; therefore, theNavy concluded manganese concentrations are due to suspended particles not dissolved in shallowgroundwater (6). Manganese levels were below comparison values. The Navy presumes that otherdetections of heavy metals are a result of suspended particles in the groundwater (6).

Unfiltered mercury was detected twice in the shallow aquifer during the RI Phase I, but was notdetected in other sampling. The maximum mercury level came from a well in the central part ofArea 6. The highest nickel concentration came from a well in the northwest corner of Area 6 and awell in the hazardous waste storage area. Nickel was detected in groundwater on the east side ofArea 6 and in two wells in the hazardous waste storage area. Vanadium maximum concentrationscame from a well in the hazardous waste storage area. The highest zinc concentrations came fromwells around the active landfill area in the southern part of Area 6. The Navy detected nitrateduring the IAS and IA investigation at levels below comparison values. Nitrate values are in thetable because levels are above comparison values in Area 5.

Area 6 - Intermediate Aquifer. SVOCs, pesticides, chlorinated herbicides, and PCBs were notdetected in the intermediate aquifer. VOCs were detected from 0.99-6 ppb; TCE was detected in awell in the former hazardous waste storage area in all three sampling phases (Table 12). During theOU1 Rapid Response and RI Phase II, chloroform (6 and 4 ppb) was detected in an off-sitemonitoring well northwest of the Area 6 former hazardous waste storage area. The Navy reportedthose concentrations were estimated and below the detection limit.

During both RI phases, vinyl chloride (3.35 and 0.72 ppb) was detected in the intermediate aquiferin an off-site monitoring well west of the former hazardous waste storage area near Goldie Road. The Navy states the well is upgradient of the former hazardous waste storage area (6). Methylenechloride was detected six times at estimated concentrations from 2-10 ppb. The Navy said that themethylene chloride was a laboratory contaminant because it was not consistently detected in allsamples and was not detected at the same level in later samples (6). The Navy considered inorganicanalyte detections to be inconsistent and random, except arsenic and lead. Detections of arsenic andlead were widespread during the RI Phase II (6). Unfiltered arsenic at 73.2 ppb was detected in anoff-site monitoring well southwest of the former hazardous waste storage area near Goldie Road; theNavy believes the source to be upgradient and off site (6). Lead was detected six times from16.5-114 ppb. Manganese was detected at a maximum of 1003 ppb. The highest lead andmanganese concentrations came from a monitoring well in the southwest corner of Area 6.

Area 6 - Deep Aquifer. VOCs were detected in the deep aquifer in a well in the former hazardouswaste storage area (Table 12). A TV camera survey showed two well pipe joints in the shallowaquifer (80 and 100 feet) were leaking, forming a path for contaminated water from the shallowaquifer to cross-contaminate the deep aquifer. Steps to remedy this situation currently are inprogress (6). Vinyl chloride and PCBs were not detected in the deep aquifer (24). Four VOCsdetected in the shallow aquifer were detected in the deep aquifer at levels less than 1 ppb; TCE and1,1-dichloroethene detections were from deep monitoring wells along the eastern and southernboundaries of Area 6 and NAS. Methylene chloride was detected four times at concentrations from6-12 ppb. The Navy said that the methylene chloride was a laboratory contaminant because it wasnot detected consistently in all samples and was not detected at the same level in later samples (6). More recent sampling results and review of data validation has clarified the qualityassurance/quality control questions and the Final RI report (June 1993) provides additionalinformation. Bis(2-ethylhexyl)phthalate (BEHP) was detected in the deep aquifer during the InitialInvestigation (II) at 2-110 ppb, and in only one sample (40 ppb) during the IA. The Navy does notconsider SVOCs to be of concern in the deep aquifer (6); however, future sampling data will help toestablish if the BEHP detections are laboratory artifacts or groundwater contaminants. Isolateddetections of 2-methyl-4-chlorophenoxyacetic acid (MCPA) (5.3 ppb) and 2,4,5-TP (0.16 ppb)below comparison values came from deep aquifer monitoring wells along the eastern and southernborder of Area 6 and NAS (6). The detection of those pesticides is puzzling, since the Navy saysthey are applied for weed control on the surface. ATSDR believes these detections may be due tosampling or analysis errors, documentation error, faulty well construction that allowed surfacecontamination to reach the deep aquifer, or surface contaminants have infiltrated through the soil tothe deep aquifer.

The highest unfiltered arsenic detections in the deep aquifer were from wells along the easternborder of Area 6; the Navy believes the source is off site (6). A single lead detection (93 ppb) camefrom a well along the eastern border of Area 6; cadmium (3-7 ppb) and chromium (20 ppb) werealso detected in that well. Two mercury (0.22 and 0.31 ppb) detections exceeded the MCL, andcame from a deep aquifer monitoring well at the northeast border of Area 6.

OU1 Ambient Air

Soil surface emission flux monitoring for VOCs was done at 36 locations during the RI at OU1,Area 6 both on and off site to the west. The emission flux isolation chamber measures VOCemissions from the soil over a small surface area. The Navy used soil gas survey results to locateemission flux sample stations (6). The Navy conducted the sampling in August 1991. Thirty-nineVOCs or metals were analyzed for in each sample. TCA was present throughout the measured areaand was being emitted at concentrations up to 120 ppb (6). TCE, 1,1-dichloroethene, and toluenewere detected less frequently at concentrations from 1-10 ppb. Benzene (1.7 ppb) and 1,1-dichloroethene (1.9 ppb) emission values were above comparison values for air. The Navy detectedthose concentrations about 400 feet northwest of the former hazardous waste storage area. Theresults were consistent with soil gas, soil, and groundwater sampling results (6).

The Navy conducted ambient air measurements and total suspended particulate and toxic metalssampling at Area 6. Sample locations were upwind and downwind of the former hazardous wastestorage and off site to the west in August 1991 at five locations. Wind measurements taken duringthe sampling showed prevailing winds from the north-northwest and south-southeast (6). Only1,1,1-trichloroethane (0.68-4.4 ppb), toluene (0.70-65 ppb), and Freon 12 (0.89-1.6 ppb) wereconsistently detected during RI sampling. Suspended particulate sampling RI results at Area 6detected lead (0.076 micrograms per cubic meter [Β΅g/m3]) and copper (1.0 Β΅g/m3). The RI indicatesthat lead was probably from nearby automobile traffic, and the copper was from the motor armatureof the sampling device (6). Freon 12 detection was infrequent. The RI considered Freon widespreadin the environment and of little significance (6).

Operable Unit 2

OU2 (Appendix A, Figure 4) consists of Area 2 (Western Highlands Landfill), Area 3 (1969-1970 Landfill), Area 4 (Walker Barn Storage Area), Area 14 (Pesticide Rinsate Disposal Area), and Area 29 (Clover Valley Road Fire School). Soil, sediment, surface water, and groundwater analyses included metals and cyanide, VOCs, SVOCs, pesticides, PCBs, organophosphorus pesticides, and chlorinated herbicides. The Navy conducted soil gas and ambient air sampling at Area 2 and Area 3 during the RI sampling in 1992; however, data were not available when this public health assessment was being written. Area 4 receives airborne contamination from the existing fire school, which is about 300 feet southwest of Area 4 (30).

OU2 Surface Soil

At Area 2, Western Highland Landfill, and Area 3, 1969-1970 Landfill, low levels of pesticideswere detected in the wetland to the east of Area 2 and southwest of Area 3 (Appendix A, Figure 4). Pesticides above comparison values or with no comparison value were detected in a single sampleabout 400 feet south and upgradient of Area 3. Soil samples were not taken from the suspectedlandfill areas.

In OU2 Area 4, Walker Barn Storage, a grid system was established across the area, and compositesamples of surface soil were collected to form twenty-three samples for analysis during the CurrentSituation Report (CSR) in 1987. All composite samples had detectable levels of PCBs. The CSRmonitoring data came from composite samples; the CSR says that a single sample could have PCBsabout eight times the level in the composite samples (2). The PCB contamination of soils wasconfirmed in 1992 at levels significantly higher than detected in the CSR (Table 13) (30).

At OU2 Area 14, the Pesticide Rinsate Disposal Area, a grid system was established. During the 1987 CSR, 100 soil samples (0-6 inch depth) were collected and composited, forming 22 samples for analysis. Composited soil samples were collected from within and around the defoliated area, but analytical results for the samples showed no detectable levels of organochlorine pesticides, chlorophenoxy herbicides, or PCBs (the detection limits used were not specified). RI sampling in 1992 detected pesticide levels above comparison values listed in Table 13. Bromacil (1.3 mg/kg), prometon (1.3 mg/kg), and lindane (0.0022 mg/kg) were also detected (31), but have no comparison values for soil.

OU2 Area 29, Clover Valley Road Fire School, is unpaved except a concrete burn pad. During the CSR, soil samples were collected at eight Area 29 locations around the perimeter of the burn pad and composited into five samples for analysis. Two other background samples were collected northwest of the burn pad. The samples were analyzed for total organic halogens, lead, PCBs, and polynuclear aromatic hydrocarbons (PAHs). The lead concentrations probably resulted from combustion of leaded fuels (Table 13). The PAH background level was 9 mg/kg, which is above comparison values. RI/FS sampling confirms the lead and PAH contamination. Twelve samples were taken from around the burn pad and to the northeast and east. Area 29 contaminants, lead and PAHs, were highest to the northeast of the burn pad, which conforms to the prevailing winter wind direction from the southwest. PAH contamination below background values, but above comparison values were detected east of the area in a drainage pond. Detection limits for PCBs varied from 0.03 mg/kg to 1.5 mg/kg due to unspecified chemical interferences (20).

Table 13.

Contaminant Concentrations at Operable Unit 2
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Surface Soil, mg/kg

mg/kg
OU2, 2 Silvex (2,4,5-TP) 16 RI/FS 16 RMEG
OU2, 4 PCB <0.05-8.7, 3/87. CSR 0.091 CREG
PCB 1.2-2600 RI/FS 0.091 CREG
OU2, 14 TCDD (total)
(tetrachlorodibenzo-p-dioxin)
0.0051 RI/FS 0.0007 EMEG
HpCDD (total)
(hexachlorodibenzo-p-dioxin)
0.0091-0.025 RI/FS 0.00011 CREG (HxCDD)
HxCDD (total)
(hexachlorodibenzo-p-dioxin)
0.0051-0.0052 RI/FS 0.00011 CREG (HxCDD)
Heptachlor epoxide 0.089 RI/FS 0.077 CREG
OU2, 29 Lead 7.6-250, 1987. CSR None
Carc. PAHs 0.13-12.8, 1987 CSR 0.12 CREG (BaP)
Lead 65.7-206 RI/FS None
Carc. PAH 3.4-35.6 RI/FS 0.12 CREG (BaP)

On-Site Sediment, mg/kg

mg/kg
OU2, 2 Lead 48-805 RI/FS None

On-Site Subsurface Soil, mg/kg

mg/kg
OU2, 4 PCB 0.78-37 RI/FS, 1'-15' 0.091 CREG
OU2, 29 Pentachlorophenol 6.2-19 RI/FS, 3' 5.8 CREG
Carc. PAH 0.71-87 RI/FS, 1' 0.12 CREG (BaP)
Lead 76.3 RI/FS, 1' None

On-Site Surface Water, ppb

ppb
OU2, 2 Total chromium <1-75 ppb, 1987 CSR 100 LTHA (CrVI)
Lead <1-35 ppb RI/FS None
benzofluoranthene 0.046-0.3 ppb RI/FS 0.006 CREG (BaP)
OU2, 29 Nickel 140 ppb RI/FS 100 LTHA
Manganese 7090 ppb RI/FS 3500 RMEG
benzofluoranthene 0.086-0.092 ppb RI/FS 0.006 CREG (BaP)

OU2 Sediment

The maximum lead value for the eight sediment samples in OU2, Area 2, was detected in wetlandeast of Area 2, near the boundary of the southern part of Area 2 (Table 13). Pesticides weredetected at levels below comparison values in 60% of the samples. In Area 14, pesticides weredetected in all four samples from a drainage ditch that flows through the area. The pesticides weredetected upstream (northwest) and were highest at and immediately downstream of the area underinvestigation. A sediment sample downstream (south) had a reduced level of pesticide (30).

OU2 Subsurface Soil

At Area 4, PCB concentrations above comparison values were detected to a depth of 15 feet, andlevels were much lower in subsurface soils compared to surface soils. At Area 29,pentachlorophenol and PAHs above comparison values were detected at depths of 1 to 30 feetduring the RI sampling in 1992 (Table 13) The maximum pentachlorophenol was detected at a 3-foot depth during drilling of a monitoring well in a former waste liquid surface impoundment acrossthe Rocky Point road and northeast of Area 29 (8); the level was 17,000 mg/kg at a 1-foot depth. Metals, VOCs, and PAHs were detected in soil samples taken when drilling monitoring wells.

OU2 Surface Water

At OU2, three surface water samples were collected and analyzed during the Current SituationReport in 1987 (Table 13). Two samples were collected and analyzed from just east of Area 2 inthe wetland area and the third surface water sample was taken from an ephemeral stream drainingthe wetland to the east (just south of Area 3). The Navy conducted sampling once during the wetseason (March) and once during the dry season (July). The cadmium concentration reported in thePreliminary Public Health Assessment and Current Situation Report of 61 ppb at Area 2 wascorrected to 0.6 ppb based on analytical confirmation of a duplicate sample with the analyticallaboratory (20). The 0.6 ppb chromium value is below comparison values. The unspeciatedchromium (55 ppb, dry season) was believed to come from landfill leachate contaminating thesurface water (20). During the RI, lead was detected in a sample taken during the dry season. ThePAH values were detected near the north end of Area 2; the current fire school is also near the northend of Area 2.

In Area 29, PAHs were detected above comparison values in a drainage ditch near the northern endof the area. Flow in the ditch is to the east. No PAHs were detected in the surface water sampletaken near the concrete burn pad. Manganese and nickel above comparison values, and arsenic andchromium below comparison values were detected in the sample near the burn pad.

OU2 Groundwater - Monitoring Wells

Eleven groundwater monitoring wells were installed around the perimeter of Area 2, and sampleswere collected in the dry season during the Current Situation Report in 1987. Three monitoringwells were installed at Area 3. At OU2, a groundwater divide may be present in the main aquiferbeneath these Areas 2 and 3, which causes groundwater under Area 2 to flow westward toward theStrait of Juan De Fuca, and groundwater under the wetland and Area 3 to flow east. There are alsoareas of perched groundwater under both areas that may be recharged by surface water from thewetlands or may seep into the wetlands thereby creating a conduit for contamination of two media. Samples were analyzed for cadmium, chromium, and lead. The Navy conducted sampling onceduring the wet season (March) and once during the dry season (July). The sampled water in severalwells was a greenish color (8). Water in the perched zone also showed iron concentrations up toseveral times higher than in the main aquifer, and an oily substance was observed in several wells(Table 14). Cadmium was detected at levels above comparison values in a shallow well near thecenter of Area 2. Wells sampled during the RI detected arsenic and chromium at levels abovecomparison values. Preliminary RI data show that high metal levels in groundwater seem to comefrom wells around the periphery of Areas 2 and 3 and near Area 3; additional data are needed to findpossible causes of this pattern.

Three groundwater monitoring wells were installed on OU2 Area 14. Samples were analyzed fororganochlorine pesticides and chlorophenoxy herbicides during the CSR, but no compounds weredetected at the detection limits (which were not listed) (2). Data from the subsequent RI/FS showedpesticides, VOCs, and SVOCs (Table 14). The highest concentrations of pesticides were detected ina monitoring well near the north end of the area of dead vegetation in Area 14. Pesticideconcentrations were also elevated in a monitoring well in the dry well. CN (chloracetophenone),which is an ingredient in chemical Mace, and low levels of chemicals associated with firesuppression foam were detected. ATSDR does not know the source of those chemicals. CN and1,2,4-trimethylbenzene do not have comparison values. The CN was detected in a well east and upgradient of Area 14 (30).

Four groundwater monitoring wells were installed as part of the CSR at Area 29. The CSR stated that analytical results for petroleum hydrocarbons and lead (1-7 ppb) were at or below background levels. Data from the RI/FS showed several metals and pentachlorophenol above comparison values in Area 29 groundwater (Table 14). Standing water covered most of the area at the time of the RI sampling in 1992; indicating the low permeability of the soil (30). Surface water drains to the east. Discontinuous perched water in all three wells drilled occurred at varying depths (30). The monitoring well north of the burn pad is in a perched aquifer (2), and samples from the well had the maximum chromium, manganese, and nickel listed in Table 14. High lead and arsenic was detected in a bedrock well that was dry during the CSR sampling in 1987, which suggests low permeability (2). The well is north of the burn pad.

Table 14.

Contaminant Concentrations at Operable Unit 2
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Groundwater - Monitoring wells, ppb

ppb
OU2, 2 Cadmium ND-40 (6/87) CSR 7 EMEG
Arsenic 11-31 RI/FS(a) 11 RMEG
Total chromium 44-199 RI/FS 100 LTHA (CrVI)
Lead 38-46 RI/FS None
OU2, 3 Arsenic 59 RI/FS 11 RMEG
Total chromium 30-86 RI/FS 100 LTHA (CrVI)
Lead 1-75 CSR, RI/FS None
Nickel 156 RI/FS 100 LTHA
Vinyl Chloride 22 RI/FS 0.7 EMEG
OU2, 4 Arsenic 12 RI/FS 11 RMEG
Total chromium 181 RI/FS 100 LTHA (CrVI)
Lead 33.6 RI/FS None
Zinc 3090 RI/FS 2100 LTHA
OU2, 14 Silvex 20 RI/FS 20 LTHA
2,4-D 260 RI/FS 70 LTHA
Prometon 570 RI/FS 100 LTHA
2,4-Dichlorophenol 2800 RI/FS 20 LTHA
Naphthalene 1000 RI/FS 20 LTHA
Benzene 1.3 RI/FS 1.2 CREG
1,2,4-trimethylbenzene 150 RI/FS None
CN (a-chloroacetophenone) 10 RI/FS None
OU2, 29 Pentachlorophenol 1.1-28 RI/FS 0.29 CREG
Arsenic 47-53.2 RI/FS 11 RMEG
Total Chromium 50-941 RI/FS 100 LTHA
Lead 42.6 RI/FS None
Manganese 760-9720 RI/FS 3500 RMEG
Nickel 105-1260 RI/FS 100 LTHA

OU2 Ambient Air

There are no data available on the ambient air contamination at OU2 (9).

Operable Unit 3

OU3 consists of Area 16, the Runway Ditches, and Area 31, the Runway Fire School (Appendix A, Figure 5). This operable unit was formed because Areas 16 and 31 are next to each other and contaminants in Area 31 flow into Area 16. As part of the CSR, soil and sediment samples were collected in March 1987 at nine locations along ditches in Area 16. Two arresting gear on runway 31-13 in Area 16 have tanks that collect ethylene glycol from the arresting gear. If the amount of glycol exceeds the capacity of the tanks, the excess is piped to the nearby grasslands. Sampling and analysis of the grassland soils is scheduled for the fall of 1992 (7). Soil and sediment analyses included metals, PCBs, and PAHs. Groundwater samples were analyzed for lead. Additional samples taken during the RI will be analyzed for marine sediments, lagoon fish and shellfish, and marine shellfish. Pesticide sampling is not scheduled for Area 31 (32). Lead concentrations are shown in the table of contaminants because ATSDR has not developed ingestion and dermal contact comparison values for lead that is detected in soil or sediment.

OU3 Surface Soil

At Area 16, the Runway Ditches, four soil samples from the top three inches of soil from the ditchbanks were collected for compositing into two samples for analysis. Four soil samples were alsocollected from a common dredge spoil disposal area for analysis. Samples were composited at eachlocation using equal weights of each sample. The top three inches of soil were sampled. PAHsabove comparison values (Table 15) and arsenic (6.5-170 mg/kg) were detected (2). The higharsenic came from a sample near the boundary of NAS, where the runway ditches flow off site Petroleum hydrocarbons were detected in 40% of the soil samples at levels as high as 30,000 mg/kg(3% by weight) (2), which was detected in a sample next to the flight line and near the hanger areaand Area 19, Fuel Truck Depot. The maximum lead levels in soil and sediment were also detectedat that location.

Soil and standing water at Area 31, Runway Fire School, had an oily sheen during the IAS and CSRinvestigations. Soil samples were collected in March 1987 from 16 locations around the burn padand near the lowland marshy area during the CSR. Analysis was done on composite samples. Samples collected from around the burn pit were composited into four samples for analysis. Samples collected along a drainage between the burnpit and the marshy area were composited, andsamples collected in the marshy area were composited. Two samples collected in an area of deadvegetation were composited. The top three inches of soil were sampled at each location. Analysis ofPCB combustion products was not done as part of the CSR. PAHs and PCBs were detected abovecomparison values (Table 15). The highest PAHs were detected in samples taken around the burnpad, to the south and southeast. PAHs were also detected downstream of Area 31 in the marsh thatdrains to the runway ditches; the highest PCB detection was also in the marsh. Lower levels ofPCBs were detected around the burn pad. The lower levels could indicate that actual PCBconcentrations were diluted by the compositing of samples, or that PCB contaminated soils were washed downstream into the marsh.

Table 15.

Contaminant Concentrations at Operable Unit 3
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Surface Soil, mg/kg

mg/kg
OU3, 16 Lead 2.9-310 mg/kg 3/87 CSR None
Carc. PAH 0.19-1.72 mg/kg CSR 0.12 CREG (BaP)
OU3, 31 Lead 62-310 mg/kg, 3/87 CSR None
Carc. PAH ND-2.15 mg/kg CSR 0.12 CREG (BaP)
PCB 0.10-4.14 mg/kg 3/87 CSR 0.091 CREG

On-Site Sediment, mg/kg

mg/kg
OU3, 16 Lead 2.8-1000 mg/kg 3/87 CSR None
Carc. PAH 0.04-5.98 mg/kg CSR 0.12 CREG (BaP)

Carc. PAH (carcinogenic PAH) - benzo(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, ideno(1,2,3-cd)pyrene, dibenz(a,h)anthracene, benzo(g,h,i)perylene

OU3 Sediment

Sediment samples for OU3, Area 16, the Runway Ditches, were taken in March 1987 from ninelocations. At each location, six sediment samples were collected from the bottom of the ditches forcompositing into two samples for analysis. Concentrations of PAHs, heavy metals, and petroleumhydrocarbons above background concentrations were detected in ditch sediments (Table 15). Petroleum hydrocarbons as high as 30,000 mg/kg were detected in almost all ditch sediments andsoils. A fuel scan during the CSR showed that the primary fuel contaminant was diesel #2. Alleleven analyzed metals were detected at that sample station where the high petroleum hydrocarbonwas detected. Unspeciated chromium (25-88 mg/kg) was detected below comparison values, andthe maximum chromium was detected near the flight line station where the sample with themaximum petroleum hydrocarbon was taken. Arsenic was detected at levels below comparisonvalues; the sample showing 52 mg/kg came from the central area of the runways. Lead wasdetected; however, there is no comparison value available for lead in soil. The location of thesample with the highest lead level was discussed in the soil section. The CSR used backgroundconcentrations for arsenic and lead of 4.7 mg/kg and 1.5 mg/kg, respectively (2). PAHs weredetected above comparison values; the maximum PAH concentration was detected near the flightline station where the sample with the maximum petroleum hydrocarbon concentration was detected.

OU3 Surface Water

Surface water testing was not performed during the Initial Assessment Study or Current SituationReport at OU3; however, both reports mention standing water at Areas 16 and 31 having an oilysheen. This observation was confirmed during the ATSDR site visit.

OU3 Groundwater - Monitoring Wells

Groundwater was not sampled at Area 16 during the Current Situation Report (CSR). In April1987, four groundwater monitoring wells were installed at Area 31, as part of the CSR. Welllocations were selected to provide data at the former burn pad and nearby surface drainages. Onewell was in a perched water zone above the local water table. The other three wells are in the watertable aquifer. Groundwater is 12 to 20 feet deep, and groundwater flow is believed to be south-southwest. The perched water zone is at a depth of five feet (2). Low levels of lead (ND-2 ppb) andpetroleum hydrocarbons were detected.

Operable Unit 4

OU4 consists of the Seaplane Base areas (Appendix A, Figure 6), Area 39 (Auto Repair and PaintShop), Area 41 (Buildings 25 and 26 Disposal Area), Area 44 (Seaplane Base Nose Hangar), Area48 (Seaplane Base Salvage Yard), and Area 49 (Seaplane Base Landfill). Groundwater is not inuse at Seaplane Base; however, Base Well No. 5 is in the family housing area. Soil, sediment,surface water, and groundwater sampling will be conducted during the RI and will include analysisfor metals and cyanide, VOCs, SVOCs, pesticides, PCBs, organophosphorus pesticides, andchlorinated herbicides. Pesticide and PCB sampling is not scheduled at Area 39 or Area 44. Sampling of other Seaplane Base areas was performed during the HWES.

OU4 Soil

At OU4 Areas 39, 41, 44, and 48/49, VOCs, PAHs, SVOCs, and metals were detected abovecomparison values (Table 16). Pesticides and PCBs were detected at Areas 41 and 48/49 abovecomparison values. Organophosphorus or chlorinated pesticides were not detected. Compositesamples were taken at 0-2 inch depths and 2-15 inch depths (14). Data tables in the Navy's 1992Initial Screening of Contaminants (ISC) for OU4 did not differentiate detected compounds bysample depth or location. Contaminants above comparison values listed in Table 16 for soil are forunspecified depths. Lindane was detected at Area 41 (21 mg/kg) and Areas 48/49 (2.9-13 mg/kg), but has no comparison value for soil.

Table 16.

Contaminant Concentrations at Operable Unit 4, Seaplane Base
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Soil at unspecified depth, mg/kg

mg/kg
OU4, 39 Carc. PAH 276-6200 mg/kg ISC, 2/92 0.12 CREG (BaP)
n-Nitrosodiphenylamine 140J-490 mg/kg ISC, 2/92 140 CREG
Lead 2.9N-736 mg/kg ISC, 2/92 None
41 Carc. PAH 124-815 mg/kg ISC, 2/92 0.12 CREG (BaP)
n-Nitrosodiphenylamine 84BJ-250J mg/kg ISC, 2/92 140 CREG
4,4-DDT 6.1P-380 mg/kg ISC, 2/92 2.1 CREG
4,4-DDD 1.6JP-13P mg/kg ISC, 2/92 2.9 CREG
4,4-DDE 0.57P-48 mg/kg ISC, 2/92 2.1 CREG
PCB 26JP-780P mg/kg ISC, 2/92 0.091 CREG
Dieldrin 9.2P mg/kg ISC, 2/92 0.044 CREG
Heptachlor epoxide 4.5P mg/kg ISC, 2/92 0.077 CREG
Lead 1.8-298 mg/kg ISC, 2/92 None
OU4, 44 Methylnaphthalene 1300-6900E mg/kg ISC, 2/92 None
Naphthalene 560-79,000E mg/kg ISC, 2/92 None
Carc. PAH 1188 mg/kg ISC, 2/92 0.12 CREG (BaP)
n-Nitrosodiphenylamine 600B-910B mg/kg ISC, 2/92 140 CREG
Pentachlorophenol 44-200J mg/kg ISC, 2/92 5.8 CREG
Lead 2.9-4400N mg/kg ISC, 2/92 None
Mercury 0.02-3.3 mg/kg ISC, 2/92 None
OU4, 48/49 Benzene 180 mg/kg ISC, 2/92 24 CREG
Carc. PAH 96-6200 mg/kg ISC, 2/92 0.12 CREG
n-Nitrosodiphenylamine 92BJ-300B mg/kg ISC, 2/92 140 CREG
4,4-DDT 0.46J-38 mg/kg ISC, 2/92 2.1 CREG
4,4-DDD 0.42JP-5.9P mg/kg ISC, 2/92 2.9 CREG
4,4-DDE 0.24J-26.4 mg/kg ISC, 2/92 2.1 CREG
PCB 40P-220P mg/kg ISC, 2/92 0.091 CREG
Dieldrin 0.31JP mg/kg ISC, 2/92 0.044 CREG
Heptachlor epoxide 0.46JP-1.5JP mg/kg ISC, 2/92 0.077 CREG
gamma-Chlordane 0.48JP-2.2P mg/kg ISC, 2/92 0.54 CREG
Lead 154N mg/kg ISC, 2/92 None

Data from the Initial Screening of Contaminants and Conceptual Site Models Technical Memorandum, Operable Unit 4 (ISC) are not validated.


Table 17.

Contaminant Concentrations at Operable Unit 4, Seaplane Base
OU, Area Contaminant Min&Max Level for Each Contaminant Reference and Max. Area Comparison Value Source

On-Site Sediment, mg/kg

mg/kg
OU4, 41 Carc. PAH 84J-115J mg/kg ISC 0.12 CREG (BaP)
Lead 2.4-151 mg/kg ISC None
Mercury 0.01-0.24 mg/kg ISC None None
OU4, 44 Lead 2.9 mg/kg ISC None

On-Site Groundwater - Monitoring wells, ppb

ppb
OU4, Unknown Vinyl chloride 2J-10 ISC 0.7 EMEG
35, 36 Benzene 0.011-980E HWES, 36 1.2 CREG
bis(2-ethylhexyl)phthalate 2-6 HWES, 36 2.5 CREG
methylene chloride 7B-11 HWES, 35 4.7 CREG
Antimony 16.6-44 HWES, 36 3 LTHA
Arsenic 3.5-87.5 HWES, 35 11 RMEG
Beryllium 0.10-5.3 HWES, 36 0.0081 CREG
Cadmium 2.0-15.2 HWES, 35 7 EMEG
Total Chromium 20.6-620 HWES, 36 200 RMEG(CrVI)
Lead 4.0-5920 HWES, 35 None
Manganese 1630-241,000 HWES, 36 70,000 RMEG
Mercury 0.1-3.6 HWES, 35 2 LTHA
Nickel 112-1030 HWES, 35 100 LTHA
Thallium 0.1-3.6 HWES, 35 0.4 LTHA
Vanadium 18.4-860 HWES, 36 20 LTHA
Zinc 23.3-11,110 HWES, 36 2100 LTHA

Organic qualifiers
B=Analyte also detected in blank samples
E=Actual value greater than upper calibration range
J=Reported concentration less than sample quantification limit
P=Greater than 25% difference between the primary and confirmation gas chromatograph columns

Inorganic qualifiers
B=Reported concentration less than contract required detection limit but greater or equal to instrument detection limit
E=Estimated because of interferences
N=Spike sample recovery not within control limits

OU4 Soil Gas

Methylene chloride (16 ppm) was detected in one soil gas sample near Area 45, TCE Tank, at Seaplane Base during the HWES. The methylene chloride was detected in a sample from the opposite side of Building 14 from the suspected location of the TCE tank; additional sampling may be required to locate the tank. Low levels of VOCs (1-8 ppm) were detected at Area 35 and 36 fuel farms; heavy rains before and during the survey could have affected the sampling effort (33).

OU4 Sediment

At OU4, PAHs were detected in Area 41 above comparison values and Areas 48/49 marinesediments. Lead and mercury, which have no comparison values in sediment, were also detected inArea 41, 44, and 48/49 marine sediments (Table 17). Arsenic, cadmium, and chromium weredetected below comparison values. Only summary data were provided in the ISC, so data trendscould not be determined. The marine sediments were collected at 0-4 inch, 4-20 inch, and 20-36inch depths; however, data tables did not differentiate detected compounds by depth or location (14).

OU4 Surface Water

During the RI for OU4, one surface water sample was collected from the wetland near Area 48/49;other sample sites were dry. The Initial Screening of Contaminants (ISC) only reported methylenechloride (3J ppb) and benzo(a)anthracene (5.5 ppb) data were available. Specific sampling siteswere not given in the document.

OU4 Groundwater - Monitoring Wells

During the RI for OU4, VOC and metals were detected above comparison values at severalSeaplane Base sites (Table 17). Most of the maximum detected contaminant levels were at Area 35,Fuel Farm 2, and Area 36, Fuel Farm 1. During the RI, vinyl chloride was detected in fourmonitoring wells. VOCs and SVOCs were detected, but location information was not given. Groundwater is not used at OU4.

Operable Unit 5

OU5 is a proposed OU that includes Area 1 (Beach Landfill) and Area 52 (Jet Engine Test Cell). Area 52 is next to Area 1 (Appendix A, Figure 7). Groundwater is not in use in OU5. Area 1 was investigated during the CSR and HWES. Area 52 was investigated in 1987, 1988, and 1989 as part of a Site Characterization Report (34). During the HWES, sandpoint monitoring wells, sediment, and surface water were sampled at Area 1. At Area 1, sediments were analyzed for VOCs, SVOCs, pesticides, PCBs, and metals during the CSR and HWES. Groundwater was analyzed at Area 52 for VOCs and SVOCs (34). Subsurface soils were sampled and analyzed for petroleum hydrocarbons, fuel hydrocarbons, VOCs, SVOCs, metals, pesticides, and PCBs.

OU5 Soil

The Navy did not sample surface soil (<3 inches) at OU5. Soil less than 1 foot was sampled duringthe Hazardous Waste Evaluation Study (HWES), and detected contaminants were belowcomparison values. Lead (14.1 mg/kg), vanadium (75.1 mg/kg), and zinc (80.5 mg/kg) do not havesoil comparison values.

OU5 Sediment

The Navy sampled sediments at OU5 from a wetland in Area 1, Beach Landfill. The HWESdetected several metals above comparison values as shown in Table 18. BEHP and PCBs weredetected at levels several times higher than comparison values. Unspeciated chromium was detectedat 21.7 mg/kg.

OU5 Subsurface Soil

The Navy conducted site characterizations of OU5 Area 52, the Jet Engine Test Cell in 1987, 1988,and 1989. Two soil borings, two test pits, and soil resistivity surveys were completed west of theexisting test cell during a geotechnical study for the installation of a second test cell. Petroleumhydrocarbons were detected in test pits east-northeast of the existing test cell. Additional soilsamples were collected at 2.5-foot deep intervals; samples to depths of 15 to 25 feet came fromtwelve hollow-stem auger borings. Soil samples to depths of 31 to 47 feet came from three cabletool borings. Total petroleum hydrocarbons (2100 mg/kg) and JP-5 (750 mg/kg) were detected(34). Cadmium (0.81-2.5 mg/kg) was detected in soil. The background cadmium concentration insoil was 0.3 mg/kg (34). Total petroleum hydrocarbons (2100 mg/kg) and JP-5 (750 mg/kg) weredetected (34).

OU5 Surface Water

The Navy sampled a wetland area in OU5 Area 1 during the HWES. Several metals were detected,but only beryllium was above comparison values (Table 18). VOC and SVOC detections were notconclusive and may be a result of sampling or laboratory contamination (13).

OU5 Groundwater - Monitoring Wells

Groundwater is not used in OU5. During the HWES, the Navy installed and sampled five wellsdrilled on the downgradient western edge of the Area 1 landfill, along the Strait of Juan de Fuca(Appendix A, Figure 7). Bis(2-ethylhexyl)phthalate (BEHP) and methylene chloride were detectedabove comparison values (Table 19). The HWES report showed BEHP in four of five monitoringwells and methylene chloride detections in all five wells. The highest BEHP came from the well inthe south central edge of the landfill. Ten heavy metals exceeded comparison values.

Table 18.

Contaminant Concentrations at Operable Unit 5
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Sediment, mg/kg

mg/kg
OU5, 1 Bis(2-ethylhexyl)phthalate 75J-2000J
7/91
HWES 50 CREG
Methylene chloride 3 mg/kg HWES 93 CREG
PCB (Aroclor 1254) 0.780J HWES 0.091 CREG
Beryllium 0.17-0.38 HWES 0.16 CREG
Lead 23.3-676 HWES None
Vanadium 30.6-54.5 HWES None
Zinc 61.5-608 HWES None

On-Site Surface Water, ppb

ppb
OU5, 1 2-methylnaphthalene 45 ppb HWES 20 LTHA, naphthalene
Methylene chloride 6B-9B ppb HWES 4.7 CREG
Bis(2-ethylhexyl)phthalate 2J-6J ppb HWES 2.5 CREG
Beryllium 0.30-0.30 ppb HWES 0.0081 CREG
Lead 2.2-779.0 ppb HWES None

At Area 52, one monitoring well was installed in 1987. A follow-up investigation in 1988 led to theinstallation of nine monitoring wells and to the completion of an electromagnetic survey to map theextent of any free product lens (34). Phase I area characterization was completed in August 1990and included the installation and sampling of six monitoring wells. Nine monitoring wells wereinstalled at Area 52 between December 1990 and January 1991 for Phase II (Appendix A,Figure 14).

Free-phase petroleum hydrocarbons are present beneath most of Area 52. The JP-5 constituentsinclude benzene, chlorobenzene, 1,4-dichlorobenzene, 1,3-dichlorobenzene, 1,2-dichlorobenzene,ethylbenzene, toluene, m-p-xylene, and o-xylene at concentrations 10-2000 times comparisonvalues. Product varies in thickness up to 1.5 feet and may extend 300 feet southwest to a localsurface depression and 300 feet northeast toward the intersection of Saratoga and Charles PorterWay (34). Low levels of total xylenes (0.37J-0.78J ppb) were detected in intertidal drive pointsamples to the north of the area (34). Groundwater under Area 52 flows from east-southeast tonorth-northwest, discharging to the Strait of Juan de Fuca. High tide reverses flow toward thenortheast and southwest for limited periods of time (34).

Table 19.

Contaminant Concentrations at Operable Unit 5
OU, Area Contaminant Min&Max Level for Each Contaminant Reference Comparison Value Source

On-Site Groundwater Monitoring Wells, ppb

ppb
OU5, 1 Methylene chloride 8B-10B ppb HWES 4.7 CREG
Bis(2-ethylhexyl)phthalate 2-90 HWES 2.5 CREG
Antimony 20.6-20.6 HWES 3 LTHA
Arsenic 2.0-12.4 HWES 11 RMEG
Barium 14.1-120 HWES 2500 RMEG
Beryllium 0.30-0.31 HWES 0.0081 CREG
Total Chromium 10.6-175.0 HWES 100 LTHA (CrVI)
Lead 3.7-63.4 HWES None
Nickel 17.1-102.0 HWES 100 LTHA
Thallium 0.40-0.45 HWES 0.4 LTHA
Vanadium 6.4-48.0 HWES 20 LTHA
Zinc 79.4-4440 HWES 2100 LTHA
OU5, 52 Benzene ND-2800J Hart Crowser 1.2 CREG
Bis(2-ethylhexyl)phthalate ND-33B ppb Hart Crowser 2.5 CREG
cis-1,2-dichloroethene ND-7 (4/90, 12/90) Hart Crowser 0.38 CREG
Chloroform ND-5 (4/90, 12/90) Hart Crowser 5.7 CREG
Vinyl Chloride ND-63 (4/90, 12/90) Hart Crowser 0.7 EMEG
Carc. PAH ND-7.5 (4/90, 12/90) Hart Crowser 0.006 CREG (BaP)
Naphthalene ND-670 Hart Crowser 20 LTHA
2-methylnaphthalene ND-1000 Hart Crowser 20 LTHA
Chlorobenzene ND-25,000J Hart Crowser 700 RMEG
1,4-dichlorobenzene ND-300,000J Hart Crowser 75 LTHA
1,3-dichlorobenzene ND-150,000J Hart Crowser 600 LTHA
1,2-dichlorobenzene ND-650,000J Hart Crowser 600 LTHA
Ethylbenzene ND-170,000J Hart Crowser 700 LTHA
Toluene ND-120,000J Hart Crowser 1000 LTHA
Total xylenes ND-780,000J Hart Crowser 10,000 LTHA

Below the free product layer, to the west, northwest, and southwest of Area 52, several organicchemicals were detected in groundwater. Compounds detected above comparison values include thejet fuel constituents benzene, ethylbenzene, xylene, and naphthalene, and non-jet fuel compoundsvinyl chloride, 1,2-dichlorobenzene, and carcinogenic PAHs (Table 19). The highest level ofchlorinated organic compounds was detected down gradient of three potential areas that were pastsolvent-waste disposal areas. The PAHs are from an area north of the area that receives jet exhaustor automobile exhaust from the test cell, runways, and Saratoga Street.

Hazardous Waste Evaluation Study (HWES).

Twenty-six areas are being investigated to confirm the absence or presence of contamination(Appendix A, Figure 8). Twenty-one of the areas under investigation are on Ault Field, and five areon Seaplane Base. In April 1987, during the CSR, 12 groundwater monitoring wells were installedin the Ault Field Central Core Area. The Navy thought the Central Core Areas could potentiallycontaminate shallow groundwater and Base Well No. 4 (2). The Central Core Areas are part of the26 areas in the HWES. HWES sampled subsurface (>3 inches depth) soils, sediments, surfacewater, and groundwater, analyzing them for EPA Target Compound List analytes. Tests includedVOCs, SVOCs, pesticides, PCBs, and metals.

HWES Subsurface Soil

The HWES identified VOCs and metals in subsurface soil from the Ault Field Central Core Area. Several metal concentrations were above relevant comparison values. At Ault Field, soils from lessthan 1 foot depth were sampled at several areas. Arsenic (2.1-11.9 mg/kg), beryllium (0.34-0.61mg/kg), and lead (2.5-107.0 mg/kg) were detected. The highest concentrations came from flightline areas in the Ault Field Central Core. The lead concentration at Area 13 was the highestdetection in soil in the HWES Ault Field areas. During the CSR, soil samples were collected atArea 25 (Building 120 Transformer Service Area) in the Ault Field Central Core Area whiledrilling monitoring wells. Concentrations of PCBs were below comparison values. The HWES didnot detect PCBs at Area 25 (13).

At Area 53, Polnell Point Ordnance Burn Area, subsurface soils were tested for ordnancecompounds. No contamination was found, and no groundwater was encountered. HWESrecommended no further sampling except to remove the burn bins (13).

HWES Soil Gas

During the HWES, soil gas was sampled from November 19 to December 11, 1990 at 16 of theHWES areas (16); 93 locations were evaluated. Soil gas samples were analyzed for VOCs andsolvents, and the results were used to select boring and monitoring well locations. Each sample wastested for target VOCs based on area history. Sample depths ranged from 1 to 12 feet. A total of110 soil gas samples were analyzed for VOCs. VOCs within soil were detected at various IRP areasin the Central Core Area and Seaplane Base. Benzene (25 ppm), ethylbenzene (5,300 ppm), andtetrachloroethylene (1 ppm) were detected in the Central Core Area.

HWES Surface Water

Bis(2-ethylhexyl)phthalate (2J-250E ppb) was detected in a surface water sample from a stream that originates from a spring beneath Area 9, Asphalt Plant Disposal Area. Other SVOCs (1-17 ppb) that could be laboratory contaminants were also detected in surface water. Methylene chloride was detected at 2-5 ppb, but was also detected in QA/QC samples that serve to verify data reliability (13). The Navy did not sample the drainage ditch at Area 15, PD-680 Spill. Further field investigations for ordnance compounds including Otto fuel were recommended by the Navy (36).

HWES Groundwater - Monitoring Wells

Ault Field Central Core Area (Appendix A, Figure 9). The maximum levels for cadmium (<0.05-2.7 ppb), chromium (<.05-31 ppb), and lead (<1-32 ppb) were detected in wells in the southwesternpart of the area (2). In 1965, a fuel spill from Area 13, Fuel Farm 3 in the Central Core Area,flooded the theater parking lot and basement (Building 118). Two monitoring wells are north anddown gradient from the area; a third monitoring well was installed next to the theater building by theHWES. The northwest well has 2.5 feet of floating product in it (13). No petroleum hydrocarbonswere detected in other wells. The Navy proposes to remove the floating product.

Several metals in groundwater sampled during the HWES are above comparison values. Thehighest concentrations of metals are associated with fuel spill areas or the flight line Ault FieldCentral Core Areas. The highest concentrations of nine metals in groundwater monitoring wellswere from Area 18, Ault Field Nose Hanger, which is on the flight line runway area. Those Area 18metals include arsenic (194 ppb), beryllium (8.2 ppb), cadmium (6.7 ppb), unspeciated chromium(962 ppb), manganese (14,500 ppb), nickel (2030 ppb), and vanadium (1270 ppb), which wereabove comparison values. Lead was detected at 285 ppb, which is above the EPA action level of 15ppb.

Groundwater is currently not in use in the Central Core Area. Base Well No. 4 was sampled duringthe Current Situation Report in 1987, and unspeciated chromium (1.6 ppb) was detected belowcomparison values. Lead was detected at 5 ppb, which is below the EPA action level.

On-Site Biota

The Navy did not sample on-site food chain entities.

C. Off-Site Contamination

ATSDR searched the Toxic Chemical Release Inventory (TRI) to identify facilities that couldcontribute to the contamination at NAS. EPA developed the TRI database from chemical releaseinformation provided by certain industries. This database includes the annual quantity of toxicchemicals discharged into each environmental medium (e.g., air, water, land) by manufacturingfacilities that employ more than ten people and are in Standard Industrial Classification Codes 20through 39. NAS Whidbey Island is not a manufacturing facility and therefore not subject to thatreporting requirement. The information for this search includes data for 1987-1990. No chemicalreleases were recorded in Island County for the NAS contaminants detected above comparisonvalues.

Off-Site Sediment

In 1987, during the Current Situation Report, intertidal and subtidal sediment samples werecollected from Oak Harbor and Crescent Harbor as part of the Seaplane Base area investigation. Subtidal sediments were analyzed for cyanide, metals, VOCs, PCB, pesticides, base acid neutralextracts, and petroleum hydrocarbons. Arsenic (3.6-19 mg/kg) and lead (1.8-7.3 mg/kg) weredetected in core samples of sediment from Oak Harbor and Crescent Harbor. Maximum levels forarsenic and lead were detected in the core samples from Crescent Harbor. Cadmium (0.02-0.32mg/kg), chromium (11-44 mg/kg), and nickel (15-51 mg/kg) were also detected. Arsenic,chromium, and nickel are below comparison values. Lead concentrations are shown in the table ofcontaminants because ATSDR has not developed ingestion and dermal contact comparison valuesfor lead that is detected in sediment. No VOCs, base-acid-neutral extractables, pesticides, or PCBswere detected in sediment samples (2).

Off-Site Surface Water

Off-site surface waters were sampled in spring and summer of 1992 (32). Results from thosesamples were not available at the time this Public Health Assessment was being written.

Off-Site Shellfish

Samples of mussels, horse clams, little neck clams, and butter clams at 14 stations from Oak Harborand Crescent Harbor were collected during the CSR in 1987. Arsenic, cadmium, and lead levels arebelow the background levels cited in the CSR for Puget Sound shellfish (Table 20). Onlychromium (0.19-3.3 mg/kg) and nickel (0.42-2.7) were above the stated Puget Sound referenceconcentrations of 0.5 mg/kg and 0.91 mg/kg, respectively. The highest chromium value was from asingle butter clam sample; however, chromium was detected at a lower level in the duplicate butterclam sample from the same station. The CSR says that the highest chromium value could haveresulted from sampling or analytical error (2). Chromium was above reference values at fivestations around the western Seaplane Base peninsula. Nickel was detected above reference values insamples from nine sites. Bis(2-ethylhexyl)phthalate (0.3 mg/kg) was detected in a single musselsample taken near Area 53, Polnell Point. No VOCs, pesticides, or PCBs were detected in shellfishsamples at the detection limits used (which were not given). Additional shellfish and fish samplingis scheduled for the RI for OU4 in 1992. No pesticides or VOCs were detected in shellfish samplesanalyzed during the CSR.

Table 20.

Contaminant Concentration in Off-Site Shellfish
Oak Harbor Crescent Harbor
Contaminant Min&Max Level 6/87 mg/kg Min&Max Level 6/87 mg/kg Puget Sound Reference Conc. mg/kg Reference Comparison Value
mg/kg Source
Arsenic 0.48-1.3 0.4-2.7 32.0 CSR None
Cadmium 0.13-0.68 0.08-0.89 1.3 CSR None
Lead <0.04-<0.05 <0.04-0.13 1.3 CSR None
Mercury <0.01-<1.01 <0.01-0.08 0.12 CSR None
Nickel 0.86-1.7 0.42-2.7 0.91 CSR None

Off-Site Groundwater - Monitoring Wells

The Navy sampled and analyzed off-site groundwater during the RI for OU1. Seven off-site shallowaquifer monitoring wells, installed during a 1988 EPA investigation of Oak Harbor Landfill, weresampled during the OU1 RI. Oak Harbor Landfill forms part of the southern boundary of Area 6and NAS (Appendix A, Figure 15). The highest vinyl chloride concentration (3.79 ppb) came fromthe Oak Harbor landfill monitoring well near the southwestern corner of Area 6 (Table 21). Thehighest arsenic and lead concentrations came from monitoring wells in the north central part andsoutheast part of Oak Harbor landfill, respectively. Four monitoring wells were installed during theRI for OU1 west of Area 6. The highest lead and zinc levels came from a monitoring well about800 feet southwest of the Area 6 former hazardous waste storage area.

Off-Site Groundwater - Private Wells

The Washington State Hazardous Waste Cleanup Act directs the Department of Social and Health Services (DSHS) to monitor drinking water supplies potentially affected by releases of hazardous chemicals. In October 1988, DSHS sampled 13 drinking water wells within a 1-mile radius of Area 6 and the Oak Harbor landfills to assess the impact of potential contaminant migration from OU1 (36). Most of the wells were screened in the shallow aquifer, two or three were in the intermediate aquifer, and one well intercepted the deep aquifer. No VOCs were detected in any of the drinking water wells. Bis(2-ethylhexyl)phthalate (8 ppb) detected in one well and QA/QC sample (4000 ppb) were attributed to laboratory contamination or plastic well casing (Table 21). Arsenic was detected at levels (ND-24 ppb) below the EPA drinking water MCL (50 ppb) (36).

Table 21.

Off-Site Contaminant Concentrations in Groundwater at Operable Unit 1
OU, Area Contaminant Min&Max Level for Each Contaminant Reference
AII, 6/90
RI, 7/91
Comparison Value, ppb Source

Off-site Groundwater - Monitoring Wells near OU1, ppb

Vinyl chloride ND-3.79 AII, IA, RI 5 CREG
Arsenic 2.5BJ-6.1BJ AII, IA, RI 0.02 CREG
Cadmium ND-9.8J AII, IA, RI 7 EMEG
Lead 1.3B-103J CSR, AII, IA, RI None
Zinc ND-4400J AII, IA, RI 2100 LTHA

Off-site Groundwater - Private and Public Potable Wells near OU1, ppb

Arsenicβ€ ND-34, 10/88, 12/92 Hulsman 0.02 CREG
Lead ND-24, 5/91 Hulsman None
Lead ND-5, 12/92 Hulsman None
Manganese ND-499, 10/88, 11/89 Hulsman 50 RMEG (child)
Nitrate ND-13,200, 12/92 Hulsman 10,000 MCLG

β€ WDOH research indicates background arsenic levels for Island County range from 11-45 ppb 39

Seven drinking water wells were sampled in November 1989 by DSHS; three of those wells were also sampled in October 1988. At least one well was drawing water from the shallow, intermediate, and deep aquifers (37). Chloroform (30.7 ppb), methylene chloride (0.9 ppb) and toluene (10.1 ppb) were detected in one well, and are believed to be from the preservative or residual manufacturing coatings, or oils or solvents from the installation of a new pump that had been placed in the well before the sampling (38).

In May 1991, 17 drinking water wells were analyzed by DSHS. Several wells were sampled in theprevious investigations. Chloroform (1.5 ppb) and 1,1,1-trichloroethane (0.5 ppb) were detected inone well. The owner of the well had chlorinated the well just before the sample was taken, and thereused to be an automobile repair shop on the property (37). Dichlorodifluoromethane (3.1 ppb) wasdetected in another well (37). Lead (ND-24 ppb) was detected in five wells. Those levels ofchloroform, 1,1,1-trichloroethane, and dichlorodifluoromethane are not above comparison values. In previous investigations of wells, lead levels were below detection limits (<5, <2 ppb). ATSDRdoes not know if this is a seasonal variation, a result of sampling or analytical techniques, orcontamination from an on- or off-site source. DSHS reported there were no organic compounds ofany significance in the drinking water wells, and levels of inorganic compounds were within therange of natural background levels for the area. DSHS concluded that the drinking water wells didnot appear affected by contaminants from NAS or Oak Harbor landfills.

In December 1992, the Washington Department of Health (WDOH) sampled 19 off-site drinking water wells near Area 6. The samples were analyzed for dissolved and total metals, inorganics, and VOCs. VOCs were detected below comparison values in three wells; the sources of the contamination are not known. Two of those wells were abandoned soon after they were sampled. The well owner monitors the third well quarterly as part of the WDOH VOC Monitoring Program. Arsenic (detected in six wells) and manganese (detected in 13 wells) were detected above comparison values. WDOH considered all metals detected to be consistent with those for background for Whidbey Island. The maximum lead concentration detected in this round of sampling was 5 ppb. WDOH detected nitrate in nine drinking water well samples; one sample contained 13.2 ppm, which is above comparison values. WDOH said that the nitrate detections were an indication of contamination of the wells from surface sources (39) which were not stated in the report. The source of the nitrate contamination is not known.

Off-Site Ambient Air

Off-site ambient air measurements were taken as part of the monitoring at Area 6 during August 14-17, 1991. One ambient air sampling station was off site about 1000 feet to the northwest of theformer hazardous waste storage area. Samples collected at that station detected 1,1,1-trichloroethane (ND-0.00074 ppb), chloromethane (0.29 ppb), and toluene (0.78-1.6 ppb) belowcomparison values. ATSDR has not developed inhalation comparison values for Freon 113 (0.33ppb) and freon 12 (0.90-1.1 ppb) in air. Other VOCs were not detected. The Industrial SourceComplex Short-Term air dispersing model (ISCST) was used to evaluate the impact of VOCs on thenearest people to Area 6, about 3300 feet south-southeast (Auld Holland Inn) of the site. Therewere no sample stations at or near that site. The Navy used 1,1,1-trichloroethane in the study,because it was frequently detected. Actual measurements of 1,1,1-trichloroethane stated in previousparagraphs were higher than modeled results and below comparison values (6).

D. Quality Assurance and Quality Control

In preparing this public health assessment, ATSDR relies on the information provided in thereferenced documents. Some references used to develop this public health assessment werepreliminary documents that were undergoing Navy, EPA, and state review. The Agency assumesthat adequate quality assurance and quality control measures were followed with regard tochain-of-custody, laboratory procedures, and data reporting. The validity of the analysis andconclusion drawn for this public health assessment is determined by the availability and reliability ofthe referenced information.

During the Interim Investigation of subsurface soil analyses at Operable Unit 1, the VOC acetonewas detected in 12 of 20 method blanks at concentrations from 14-29 ppb, and methylene chloridewas detected in all 20 method blanks from 5-22 ppb. No other interferences were detected. TheSVOC bis(2-ethylhexyl)phthalate (BEHP) was detected in 6 of 18 method blanks in concentrationsfrom 40-9000 ppb and in field QC sample blanks from 2-270 ppb. Those compounds were detectedin 14 of 18 method blanks associated with soil and field quality control samples (10). More recentsampling results and review of data validation has clarified the quality assurance/quality controlquestions and the Final RI report (June 1993) provides additional information.

The review of OU1 analytical results for soil and groundwater sampling of the Initial Investigationwas complicated by the contamination of several quality assurance samples analyzed with theenvironmental samples. All results of collected soil samples are suspected to be a result oflaboratory contamination or interferences; therefore, the soil data cannot be conclusively used toshow the presence of contamination in the area (10).

According to the RI for OU1, Quality Assurance measurements for reported soil gas VOCconcentrations appear to be accurate (6); however, the quality of laboratory results of other mediavaried throughout the RI. Much of the data was qualified or rejected during data validation. Seventy percent of the organophosphorus and herbicide results were rejected due to holding time orinstrument calibration deficiencies (6). To use the data, more lenient validation criteria were used inthe data validation process, resulting in previously rejected Phase I data being labeled 'estimated'during Phase II (6). The Navy says that toluene results from soil samples at OU1 are due totoluene-containing tape used to seal the sampling containers (6).

Data from OU2 RI/FS are not validated. Data are used in this public health assessment forqualitative interpretation of OU2 characterization. Remedial actions are being discussed based onthe data (30).

Phase I field work data for OU4 were invalidated by 'catastrophic laboratory failures'. Two interimsampling events were conducted to close data gaps caused by the data invalidated in Phase I (7). Data from the Technical Memorandum for OU4 were not validated (14). The data are used in thispublic health assessment for qualitative interpretation of OU4 characterization.

At OU5 Area 52, bis(2-ethylhexyl)phthalate was detected in 35% of the groundwater samplescollected in concentrations from 6.9 to 33 ppb. The levels detected were not consistent in Phase Iand Phase II sampling and are likely introduced during laboratory analysis (34). LaboratoryQA/QC data evaluation procedures indicate that the soil concentrations of methylene chloride(0.002-0.004 mg/kg) and acetone (0.010-0.053 mg/kg) were also due to laboratory contamination.

Weather during soil gas sampling for the HWES may have affected results (16). High winds, cool temperatures, and heavy rains occurred during most of the soil gas survey during the HWES. QA/QC consisted of eleven duplicates and one sample of ambient air. The report for the HWES for other media contained several data inconsistencies between analytical tables and summary tables. Units were different between two tables when discussing the same contaminant in the same area. The Installation Restoration Program coordinator said that the report was being revised (40).

E. Physical and Other Hazards

During the site visit, the ATSDR team observed that tidal and wave action at Area 1, BeachLandfill, had uncovered buried landfill items such as an old telephone pole, lumber, and pieces ofmetal and concrete. The area is not fenced, and access is not restricted. The terrain drops down tothe beach very steeply in places. Base personnel could fall and hurt themselves on the exposeddebris.

According to the Initial Assessment Study, live ordnance is sent to the Yakima Firing Range for disposal (1).


a. Data from the OU2 RI/FS is not validated.




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