PUBLIC HEALTH ASSESSMENT
SOUTH WEYMOUTH NAVAL AIR STATION
SOUTH WEYMOUTH, NORFOLK COUNTY, MASSACHUSETTS
Table 1: Potential Exposure Pathways
| Pathway Name | Source of Contamination |
Environmental Medium |
Point of Exposure | Route of Exposure |
Potentially Exposed Population | Comment |
| Groundwater in the vicinity of SWNAS | WGL RDA SL FFTA TLF STP ABTFSA Background (1,2-DCE, pesticides, and metals) |
Groundwater | Off-site private wells or future on-site wells | Ingestion Inhalation Dermal |
People using off-site private wells. It
is not known how many people are using private wells or if any wells are
contaminated.
Number of persons potentially exposed = 255 (based on 85 private wells within a 4 mile radius x 3 people living in each household.) |
Past: The site has used municipal water since its inception. Thus, on-site exposure did not present a public health hazard. Levels of off-site exposures, if any, are unknown since there is no off-site sampling data and private well usage is unknown. It is doubtful that contamination is migrating off-site because only a small PCE plume has been found within site boundaries. This plume is located in the central portion of the site and no drinking water wells are or have been located within or proximate to the plume boundaries. The Navy is conducting remedial actions to treat groundwater and prevent further migration. Present: Future: |
| Surface water and sediment in the vicinity of SWNAS | Sediment: WGL RDA FFTA TLF STP ABTFSA Background (SVOCs, pesticides, and metals) Surface water: (SVOCs, pesticides, and metals) |
Surface water and sediment (French's Stream and Old Swamp River) |
On-site and off-site surface water bodies | Ingestion Dermal |
Town of Weymouth uses drinking water supplied by Old
Swamp River. Trespassers using on-site surface water for recreation. Nearby
residents using off-site surface water for recreation. Number of potentially exposed persons = 50 to 500 |
Past: Although it is unknown whether any one was exposed to these surface water bodies and, if so, at what frequency and duration, if exposure did occur at current contaminant levels, it is unlikely to have resulted in adverse health outcomes. Present: Future: |
| On-site surface and subsurface soil | WGL RDA SL FFTA STP ABTFSA |
Soil | On-site surface and subsurface soil | Ingestion Dermal |
Current site residents and trespassers.
Numbers of potentially exposed persons = 50 to 500 |
Past: Trespassing at the air station was extremely limited because of security restrictions. On-site workers may have been in areas of contamination; however, remediation workers have proper protective equipment. Residents on the site were unlikely to contact the sources of contamination because the sites are located in restricted areas far from the Naval housing units. Present: Future: |
| WGL | West Gate Landfill | RDA | Rubble Disposal Area |
| SL | Small Landfill | FFTA | Fire Fighting Training Area |
| TLF | Tile Leach Field | STP | Sewage Treatment Plant |
| ABTFSA | Abandoned Bladder Tank Fuel Storage Area | 1,2-DCE | 1,2-dichloroethene |
| SVOC | semivolatile organic compound |
Background locations are locations that have not been impacted by site contamination. Samples from background locations contain contaminants, such as metals, that are naturally occurring.
Table 2: West Gate Landfill - Summary of Groundwater Monitoring
Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value (ppb) |
|
| child/adult | Source | |||
| Metals | ||||
| Arsenic | 2/13 |
2.8 - 21.5 |
0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 1/13 | 5 | 0.008 20/70 4 |
CREG RMEG MCL |
| Chromium | 1/13 | 2.8 - 233 | 50/200 | RMEG |
| Lead | 1/13 | 2 - 61.2 | 15 | EPA Action Level |
| Manganese | 9/13 | 5.3 - 5,430 | 50/200 | RMEG |
| Vanadium | 1/13 | 2.5 - 174 | 30/100 | EMEG (Intermediate) |
The data on Tables 2 through 11 are from Brown and Root, 1997. ATSDR also reviewed and considered additional data received in 1998 inelectronic format that includes additional CERCLA and MCP sites. This data confirmed but did not change ATSDR's conclusions about potential exposures and adequacy of safeguards to protect people identified in this report. ATSDR will review data from new sampling events in 1999, 2000 and 2001. Based on future data, ATSDR will evaluate if potential exposures remain safer than levels that would be expected to cause health effects and take steps necessary to work with stakeholders to protect public health.
Note: The following list of abbreviations applies to Tables 2 through 11.
|
CREG
|
= Cancer Risk Evaluation Guide
|
| EMEG | = Environmental Media Evaluation Guide |
| LTHA | = Lifetime Health Advisory for drinking water (EPA) |
| MCL | = Maximum Contaminant Level |
| MCLG | = Maximum Contaminant Level Goal |
| ppb | = parts per billion |
| ppm | = parts per million |
| RBC | = Risk-Based Concentration |
| RMEG | = Reference Dose Media Evaluation Guide |
1 Number of samples with contaminant detected above
comparison value / number of samples analyzed for the contaminant
2 Since the release of the public comment
draft of this PHA, EPA withdrew the cancer slope factor for beryllium, which
was used to derive the CREG. Therefore, ATSDR has also withdrawn the CREG. The
previous CREG has been included in this PHA to maintain consistency with the
public comment draft.
Note: The data presented in Tables 2 through 9 represent contaminant concentrations in samples collected from groundwater monitoring wells. These monitoring wells are for site characterization purposes only. Water from these wells is not used as drinking water and these data are not intended to represent concentrations that may be ingested from use of private wells.
Table 3: Rubble Disposal Area - Summary of Groundwater
Monitoring Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison
Value (ppb) |
|
| child/adult | Source | |||
| SVOCs | ||||
| Bis(2-ethylhexyl) phthalate |
1/8 |
27 |
3 | CREG |
| Metals | ||||
| Arsenic | 2/8 | 3.6 - 10.8 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 1/8 | 2.1 | 0.008 20/70 4 |
CREG RMEG MCL |
| Lead | 1/8 | 1.9 - 43.4 | 15 | MCL Action Level |
| Manganese | 8/8 | 220 - 14,100 | 50/200 | RMEG |
| Vanadium | 1/8 | 50.5 | 30/100 | EMEG (Intermediate) |
| Zinc | 2/8 | 22.6 - 40,800 | 3,000/10,000 | EMEG (Chronic) |
Table 4: Small Landfill - Summary of Groundwater Monitoring
Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison
Value (ppb) |
|
| child/adult | Source | |||
| Pesticides | ||||
| Heptachlor epoxide |
1/7 |
0.0061 | 0.004 0.1/0.5 0.2 |
CREG |
| Alpha Chlordane | 1/7 | 0.033 | 0.03 6/20 0.2 |
CREG EMEG (Chronic) MCLG |
| Gamma Chlordane | 1/7 | 0.032 | 0.03 6/20 0.2 |
CREG EMEG (Chronic) MCLG |
| Metals | ||||
| Arsenic | 1/7 | 2.6 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 5/7 | 0.31 -0.56 | 0.008 20/70 4 |
CREG RMEG MCL |
| Manganese | 5/7 | 28.2 - 733 | 50/200 | RMEG |
| Thallium | 1/7 | 4.8 | 0.4 | LTHA |
| Zinc | 1/7 | 56 - 3,560 | 3,000/10,000 | EMEG (Chronic) |
Table 5: Fire Fighting Training Area - Summary of Groundwater
Monitoring Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value |
|
| child/adult | Source | |||
| Metals | ||||
| Antimony | 3/9 | 23.7 - 27 | 4/10 6 |
RMEG MCL |
| Arsenic | 2/9 | 3.1 - 4.6 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 1/9 | 0.39 | 0.008 20/70 4 |
CREG RMEG MCL |
| Manganese | 9/9 | 109 - 16,400 |
50/200 |
RMEG |
| Zinc | 1/9 | 27.9 - 3,990 | 3,000/10,000 | EMEG (Chronic) |
Table 6: Tile Leach Field - Summary of Groundwater Monitoring
Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value |
|
| child/adult | Source | |||
| Metals | ||||
| Arsenic | 3/4 | 3.2 - 15.3 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 4/4 | 0.98 - 5.7 | 0.008 20/70 4 |
CREG RMEG MCL |
| Lead | 3/4 | 4.8 - 111 | 15 | MCL Action Level |
| Manganese | 4/4 | 108 - 1,110 | 50/200 | RMEG |
| Vanadium | 3/4 | 10.4 - 122 | 30/100 | EMEG (Intermediate) |
Table 7: Sewage Treatment Plant - Summary of Groundwater
Monitoring Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value (ppb) |
|
| child/adult | Source | |||
| Metals | ||||
| Manganese | 3/3 | 108 - 4,270 | 50/200 | RMEG |
Table 8: Abandoned Bladder Tank Fuel Storage Area - Summary
of Groundwater Monitoring Well Data That Exceed Comparison Values
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value
|
|
| child/adult | Source | |||
| Metals | ||||
| Arsenic | 1/4 | 3.6 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 4/4 | 0.68 - 1.2 | 0.008 20/70 4 |
CREG RMEG MCL |
| Manganese | 4/4 | 56.2 - 533 | 50/200 | RMEG |
| Vanadium | 1/4 | 5.1 - 33.7 | 30/100 | EMEG (Intermediate) |
Table 9: Perimeter Monitoring Well Summary Data
| Contaminant | Frequency
Detected Above Comparison Value1 |
Range of
Detected Concentrations (ppb) |
Drinking Water Comparison Value (ppb) | |
| child/adult | Source | |||
| Metals | ||||
| Aluminum | 1/6 | 267 - 39,500 | 37,000 50 |
RBC Secondary MCL |
| Arsenic | 3/6 | 3.9 - 7.8 | 0.02 3/10 50 |
CREG EMEG (Chronic) MCL |
| Beryllium2 | 4/6 | 0.33 - 2.40 | 0.008 20/70 4 |
CREG RMEG MCL |
| Iron | 2/6 | 341 - 36,600 | 11,000 300 |
RBC Secondary MCL |
| Lead | 2/6 | 1.7 - 24.50 | 15 | MCL Action Level |
| Manganese | 4/6 | 30.1 - 1,790 | 50/200 50 |
RMEG Secondary MCL |
| Vanadium | 2/6 | 6.3 - 71.1 | 30/100 | EMEG (Intermediate) |
Table 10: Summary of Surface Water and Sediment Data From
French's Stream That Exceed Comparison Values
| Contaminant | Frequency Detected Above Comparison Value1 |
Maximum
Detected Concentration |
Location
of Maximum Concentration |
Comparison Value (ppb) |
|
|
child/adult |
Source | ||||
|
SURFACE WATER |
|||||
| SVOCs (ppb) | |||||
| Bis(2-ethylhexyl)phthalate | 2/20 | 6.0 | FFTA | 3 | CREG |
| Pesticides (ppb) | |||||
| 4,4'-DDD | 1/20 | 0.78 | STP | 0.1 | CREG |
| 4,4'-DDT | 1/20 | 0.20 | STP | 0.1 | CREG |
| Aroclor-1254 | 1/20 | 0.78 | STP | 0.2/0.7 | RMEG |
| Metals (ppb) | |||||
| Arsenic | 3/21 | 3.2 | STP | 0.02 | CREG |
| Beryllium2 | 2/21 | 14.7 | ABTFSA | 0.008 20/70 |
CREG RMEG |
| Cadmium | 1/21 | 3.4 | ABTFSA | 2/7 | EMEG (Chronic) |
| Iron | 2/21 | 272,000 | ABTFSA | 11,000 | RBC |
| Lead | 1/21 | 113.0 | ABTFSA | 15 | MCL Action Level |
| Manganese | 17/21 | 1,670 | ABTFSA | 50/200 | RMEG |
| Vanadium | 2/21 | 228 | ABTFSA | 30/100 | EMEG (Intermediate) |
|
SEDIMENT |
|||||
| SVOCs (ppb) | |||||
| Benzo(a)anthracene | 3/26 | 3,100 | FFTA | 870 | RBC |
| Benzo(a)pyrene | 7/26 | 2,600 | FFTA | 100 | CREG |
| Benzo(b)fluoranthene | 4/26 | 1,300 | FFTA | 870 | RBC |
| Dibenz(a,h)anthracene | 3/26 | 220 | STP | 87 | RBC |
| Indeno(1,2-c,d)pyrene | 1/26 | 940 | FFTA | 870 | RBC |
| Pesticides (ppb) | |||||
| Dieldrin | 2/26 | 560 | STP | 40 | CREG |
| Metals (ppm) | |||||
| Arsenic | 26/27 | 22 | STP | 0.5 | CREG |
| Beryllium2 | 7/27 | 1.4 | FFTA | 0.008 100/1000 |
CREG RMEG |
| Iron | 2/27 | 44,900 | WGL | 23,000 | RBC |
Table 11: Summary of Surface Water and Sediment Data From
Old Swamp River That Exceed Comparison Values
| Contaminant | Frequency Detected Above Comparison Value1 |
Maximum Detected Concentration |
Location of Maximum Concentration |
Comparison Value (ppb) |
|
|
child/adult |
Source | ||||
|
SURFACE WATER |
|||||
| Metals (ppb) | |||||
| Antimony | 1/13 | 17.5 | Background | 4/10 | RMEG |
| Arsenic | 1/13 | 1.8 | RDA | 0.02 | CREG |
| Iron | 1/13 | 16,600 | RDA | 11,000 | RBC |
| Manganese | 13/13 | 3,570 | RDA | 50/200 | EMEG (intermediate) |
| Thallium | 1/13 | 5.2 | RDA | 0.4 | LTHA |
|
SEDIMENT |
|||||
| SVOC (ppb) | |||||
| Benzo(a)anthracene | 3/13 | 1,500 | RDA | 870 | RBC |
| Benzo(a)pyrene | 9/13 | 1,600 | RDA | 100 | CREG |
| Benzo(b)fluoranthene | 5/13 | 2,400 | RDA | 870 | RBC |
| Dibenz(a,h)anthracene | 3/13 | 230 | RDA | 87 | RBC |
| Pesticide | |||||
| Dieldrin | 1/7 | 55 | RDA | 40 | CREG |
| Aroclor-1260 | 1/7 | 23,000 | RDA | 400 | CREG |
| Metals (ppm) | |||||
| Arsenic | 12/13 | 8.9 | Background | 0.02 | CREG |
| Iron | 4/13 | 45,500 | RDA | 23,000 | RBC |

Figure 1. Site Map and Demographics

Figure 2. SWNAS, SNAS, and Nomans Land Island Relative Location Map

Figure 3. IRP and MCP Site Locations

Figure 5. ATSDR's Exposure Evaluation Process

Figure 6. Weymouth, Hingham, Rockland,
and Abington Boards of Health Survey of Wells

Figure 7. Weymouth, Hingham, Rockland,
and Abington Townships Orthophoto
Next Section Table
of Contents