PUBLIC HEALTH ASSESSMENT
FORT EUSTIS (US ARMY)
NEWPORT NEWS
NEWPORT NEWS COUNTY
VIRGINIA
ENVIRONMENTAL CONTAMINATION AND ENVIRONMENTAL EXPOSURE PATHWAYS EVALUATION
Introduction
This section examines the pathways for exposure to contamination at Fort Eustis. We will examine each of the media (water, air, soil, foodchain) to determine whether contamination is present, and if people in the community are exposed to (or in contact with) the contamination. If people are exposed to contamination in any of the media, we will evaluate whether there is enough contamination to pose a hazard to people in the community. This analysis will follow the pattern depicted in Figure 1, and will systematically evaluate each of the media.
Evaluation of Possible Biota /Foodchain Exposure Pathways
The FDA (U.S. Food and Drug Administration) Action Level for PCBs in fish is 2.0 parts per million (ppm), or 2,000 ppb. The Great Lakes Fish Advisory Task Force (GLFATF) uses 1.9 ppm as the maximum amount of PCB contamination in fish tissue that could be safely eaten. The GLFATF recommends that no fish be eaten that are contaminated at these levels (5). FDA and GLFATF PCB advisory levels for consumption by the general public of PCB-contaminated fish are shown in Table 2. The recommendations of the GLFATF will be referenced in recommendations made in this document. (Note: EPA Region III uses a risk-based approach to arrive at safe PCB levels that may in fact be lower than the FDA limits.)
| Table 2 - Examples of Fish Consumption Advisory Levels for PCBs in Fish |
| Food and Drug Administration (FDA) - No Consumption – 2.0 ppm |
| Great Lakes Fishing Advisory Task Force (GLFATF)
- No Consumption – >1.9 ppm "meal" is defined as consisting of an 8 ounce (raw weight) fish fillet |
Bailey's Creek
PCBs have been detected in the water and in biota samples collected from Bailey's Creek.
Samples of localized populations of fish from Bailey's Creek are contaminated above the FDA suggested limit. Based on information obtained from the RI for Bailey's Creek, PCBs in catfish muscle were detected at a maximum of 29,200 nannograms/gram, (ng/g, or parts per billion, ppb) (4). Since levels exceed FDA action levels and GLFATF advisory levels for consumption of PCB-contaminated fish, consumption of aquatic life from this creek may be hazardous. It should be noted that the levels found were determined from dry weight samples, not from whole or wet weight samples (4). (FDA and GLFATF advisories are based on wet weight analysis.) Dry weight samples are only a fraction (generally around 5 - 15 percent) of the total amount of flesh. This being the case, the actual concentrations in the whole edible portion could be 7 to 20 times lower than that found in the dry weight fraction. According to information provided by Fort Eustis, the dry weight proportion for this specific catfish was 5.51% (4). As a result, the actual concentration could be as low as 1,609 ppb (1.61 ppm). Although 1.61 ppm is below the level suggested by FDA and GLFATF for prohibiting any consumption, it exceeds the suggested GLFATF standard of 210 ppb (0.21 ppm) for limited consumption of 6 to 12 meals per year which would be possible by frequent users of this lake (5). (See Table 2).
Analysis of additional wet-weight samples collected from Bailey's Creek could clarify this matter. However, it is uncertain that much fishing occurs in the affected portions of Bailey's Creek. PCB levels may be high enough that frequent and regular consumption is not recommended. A usage survey could determine whether individual anglers use the affected areas of Bailey's Creek occurs often enough that fish consumption may be a public health hazard. However, the Army has announced plans to work with the Commonwealth of Virginia to place Bailey's Creek off-limits to anglers (6). If emplaced, this action will be protective of human health.
Eustis Lake
PCBs and other contaminants have been detected in Eustis Lake. As a result of the ongoing remedial activities at Ft. Eustis, Eustis Lake has been posted as a catch-and-release lake. Further environmental data analyses is planned to determine whether the catch-and-release measures should remain in effect.
In the text of the Draft RI for Fort Eustis, PCB levels in catfish liver tissue from Eustis Lake were cited at a maximum of 2,000 ppb, or 2.0 ppm. This level equals the FDA action level and is greater than the advisory level for the GLFATF (5). However, PCB levels in liver tissue can not be directly correlated with edible portions of the fish. In order to clarify this issue the Army has recently collected additional samples of several species of fish from Eustis Lake (10). A number of samples were collected of white catfish, largemouth bass, black crappie, gizzard shad, bluegill sunfish and carp. Of these fish, catfish, shad and carp had PCB (specifically, Aroclor 1260) levels exceeding the recommended maximum levels for safe consumption. In catfish, Aroclor 1260 levels ranged up to 2.85 ppm. In shad, Aroclor 1260 ranged to 2.63 ppm. The maximum Aroclor 1260 concentration in carp was 9.43 ppm (10). Based on the PCB levels detected, consumption of these three species is not recommended.
PCBs were detected in the bass at levels up to 0.64 ppm (Aroclor 1260). At this level of PCB contamination, consumption should be limited to about one meal per month. In crappie, Aroclor 1260 was detected at a range of up to 0.07 ppm. At this level of PCB contamination, consumption should be limited to no more than one meal per week. PCBs levels in bluegill did not appear to represent a public health hazard.
The Fort Eustis fish consumption risk assessment (10) recommends continuation of the fishing advisory prohibiting consumption of all six species. Continuation of this advisory is certainly protective of public health.
Brown's Lake
Carp and catfish muscle samples collected from Brown's Lake were found to contain total PCBs ranging from 0.094 ppm to 0.133 ppm. According to the GLFATF advisory, consumption of fish contaminated with PCBs at these levels should be limited to about one meal per week. Accordingly, Brown's Lake should continue to be included in the Fort Eustis fishing advisory. Limiting or prohibiting consumption of fish from this lake is protective of public health.
Evaluation of Possible Surface Water Exposure Pathways
People can be exposed to contaminated water by drinking it, bathing or swimming in it, or, breathing vapors in steam (for instance, in a hot shower). There are two main water pathways to consider. These pathways are:
Surface Water
Contamination of surface water is an issue of potential concern throughout Fort Eustis because of either the detection of contaminants in water or in fish inhabiting these waters. In particular, the following water bodies have documented or suspected contamination: Milstead Island Creek, Eustis Lake and Brown's Lake, and Bailey's Creek. The Warwick River comprises the eastern boundary of Fort Eustis, and is supplied in part by tributaries emanating from the installation. As a result of this geographic relationship, if contamination were to reach this water body, the possibility would exist for exposure to occur.
Milstead Island Creek
High concentrations of fuel and oil products were detected in surface water samples collected in 1993 from Milstead Island Creek. Concentrations ranged from 12,000 to 910,000 ppb. Based on ATSDR's recommendation, Fort Eustis conducted a supplementary site inspection of this area to determine a source for these contaminants and to determine if a hazard exists. Ten surface water samples were collected from Milstead Island Creek in the area where previous sampling had detected the contamination (8).
In the 1996 survey, total petroleum hydrocarbons (TPH) were not detected in any of the ten samples. The detection limit was 0.5 ppm. Even in the event that TPHs were present below the detection level, it is not likely that exposure would present a public health hazard. Milstead Island Creek is relatively remote and not likely to be regularly visited. The type of contact that would occur is expected to be dermal exposure through short-term and infrequent wading or incidental ingestion. The short-term and infrequent dermal contact that would occur, or the incidental inhalation or ingestion would not be likely to result in a public health hazard (11,12).
Eustis Lake
Although water samples were not collected from Eustis Lake, there is indirect evidence of possible PCB contamination in this lake. Catfish collected from this lake were found to have elevated PCB levels in their internal organs. For significant adverse public health effects to occur, dermal contact to relatively low levels of PCBs must be frequent and long-term. The relatively infrequent and short-term contact associated with recreational use of the lake would generally preclude significant exposure. Unless water samples from Eustis Lake are analyzed, the public health implications can not be addressed. However, it is unlikely that exposure to significant amounts of PCB will occur through contact with water from Eustis Lake.
Brown's Lake
Surface water contaminants in Brown's Lake are VOCs, fuel products, and lead (13). These chemical are not present at levels that might be of public health hazard via ingestion (drinking), and not high enough to present a hazard via short-term and infrequent dermal contact that would be expected from swimming or wading in the lake. Therefore, ingestion or dermal exposure to contaminants in water are not public health hazards at Brown's Lake.
Bailey's Creek
Only limited surface water sampling (six samples) has been done at Bailey's Creek. Low concentrations of PCBs and metals have been detected in the water samples collected (13). Based on the analysis of these samples, surface water contamination does not appear to pose a public health hazard.
Warwick River
Monitoring of two small tributaries of the Warwick River is conducted on a regular basis as a part of the RI. To date, this monitoring has not detected any appreciable contamination that might reach the Warwick River (4).
Groundwater
Groundwater is not used for domestic purposes onsite. Water for domestic use is provided by municipal water supplies (7). The water is supplied from a city reservoir located to the north of the post. As a result, there is no potential for public health hazard resulting from contact with contaminated groundwater.
Analyses of groundwater samples in the vicinity of the IRP sites on the eastern side of the facility show that contaminant plumes are small-scale and localized (13). Since this is the case, no significant contaminants have reached as far as the Warwick River, so that groundwater contaminants from Fort Eustis have not reached the main portion of the James-York Peninsula.
Evidence presented in the RI suggests that the shallow aquifer is strongly influenced by recharge from overlying surface water bodies. As a result, recharge from the Warwick River would serve as a effective barrier to any contaminant plume that might originate from under Fort Eustis.
Evaluation of Possible Sediment Exposure Pathways
The principal concern for exposure to contaminated sediments is through dermal contact. Sediment samples were collected from Brown's Lake, Bailey's Creek, and Milstead Island Creek. Samples collected from the lake and creek bottoms may not be directly accessible to people. However, these samples can provide insight into the possibility of harmful exposures for more accessible sediments, such as those along the edges of the water bodies.
Eustis Lake
Although analysis of sediment samples collected from Eustis Lake did not detect PCBs, there is indirect evidence of possible contamination found in the elevated PCB contamination found in organs from catfish collected from this lake. As in the case of surface water, for significant adverse public health effects to occur, chronic, long-term dermal contact to relatively low levels or dermal contact with extremely high levels of PCBs would be necessary. Also, the relatively infrequent and short-term contact that would be likely would generally preclude significant exposure. Until sediment samples from Eustis Lake are analyzed, the public health implications of exposure to sediment at Eustis Lake can not be addressed. However, it is unlikely that exposure to significant amounts of PCB will occur through dermal contact with the sediment of Eustis Lake.
Brown's Lake
Sediment contaminants in Brown's Lake are PAHs, PCBs, fuel products, and metals (13). The levels detected are not high enough to present a public health hazard via short-term and infrequent dermal contact or incidental ingestion that would be expected from wading along the edges of the lake. Therefore, exposure to contaminated sediment is not a public health hazard at Brown's Lake.
Bailey's Creek
Lead, PCBs and fuel products appear to be the principal contaminants present in Bailey's Creek sediment. The sampling survey of 1990 found lead levels as high as 270,000 ppm. It should be noted that the areas of high lead concentration are located within the post skeet-shooting range. The very high concentration could be considered an anomaly representing a shotgun pellet, rather than lead-contaminated sediment. Although elevated lead levels are found in these sediments, the potential for significant dermal contact and absorption is very slight for individuals who may enter the skeet range. This is because such activity would be infrequent and short term, and also because lead is not easily absorbed through the skin (14).
PCB levels as high as 400,000 ppb have been detected in sediments. This is the highest concentration found and probably is not representative of contamination throughout Bailey's Creek. However, several samples in the 1990 sampling round contained concentrations of PCBs ranging from 150 to 1,400 ppb (13).
Dermal contact with sediment at Bailey's Creek would be short-term and infrequent. Actual exposure to skin would be limited, because a tidal creek and marsh environment is not a likely site for people to walk through without shoes or boots. Dermal exposure to sediments in this situation will not result in a public health hazard (15).
Milstead Island Creek
Low levels of PAHs, VOCs, and fuel products were detected in sediments of Milstead Island Creek. Based on sampling conducted in 1990 (13), there do not appear to be contaminants present in sediment at levels that would present a public health hazard.
Evaluation of Possible Soil Exposure Pathways
Soil contamination has been documented at several of the IRP sites within Fort Eustis. The contaminants present are metals, VOCs, PAHs and petroleum fuel products. The areas are generally fenced or have public access otherwise restricted. As a result of these institutional controls (and as long as such controls are diligently maintained) these soil contamination sites do not represent a hazard to public health.
Evaluation of Possible Air Exposure Pathways
Air sampling is not planned for the remedial investigation at Fort Eustis. However, the type of activities occurring at Fort Eustis are not generally associated with the production of significant amounts of contamination into the air. As a result, there does not appear to be any significant exposure of the public to contamination via air pathways.
Evaluation of Possible Exposure to Physical Hazards
Mulberry Island has been an artillery range in the past and continues to serve that function today. As such, there is an expected hazard from unexploded ordnance. Access to this area is restricted by institutional controls and warning signs are posted. Other than access through the main post, there is no means of entry except by boat. Seasonal hunting, under strictly controlled conditions, is allowed. Hunter access to Mulberry Island is restricted to areas cleared of unexploded ordnance, and is only allowed after a safety briefing is given by post representatives. In view of these precautions, there do not appear to be any hazards associated with the artillery ranges beyond those expected in an area serving this purpose.
QUALITY ASSURANCE AND QUALITY CONTROL
In preparing this Public Health Assessment, ATSDR relies on the information provided in the referenced documents. The Agency assumes that adequate quality assurance and quality control measures were followed with regard to chain-of-custody, laboratory procedures, and data reporting. The validity of the analyses and the conclusions drawn in this document are determined by the availability and reliability of the referenced information.
The majority of the environmental data presented in this public health assessment is from the Remedial Investigation (RI) report. Generally, the methodology used in the RI is appropriate for characterizing contamination at Fort Eustis. Additional information collection is planned during completion of RI activities. This information will be evaluated by ATSDR. Conclusions and Recommendations of this PHA will be modified if appropriate and necessary.
COMMUNITY HEALTH CONCERNS
Public health concerns were investigated by ATSDR through meetings, correspondence, telephone conversations and information from Fort Eustis, EPA, state and local agency files. Draft versions of this document were provided to the Fort Eustis, the EPA, state regulatory agencies and were provided to the public repositories. All comments and suggested revisions were incorporated in this final version.
Community concerns were voiced about the PCBs levels found at Bailey's Creek. The effect on public health of this contamination is discussed in detail above. Dermal exposure to sediments in this situation will not result in a public health hazard. Elevated levels of PCB have been found in fish taken from Bailey's Creek. Because of questions on the analytical techniques used (i.e., dry-weight analyses), it is not possible to state definitively whether consumption of these fish would be a public health hazard. Additional information is needed to determine the current PCB levels and to ascertain the amount of fishing that occurs at Bailey's Creek.
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