PUBLIC HEALTH ASSESSMENT
AMENIA, DUTCHESS COUNTY, NEW YORK
Environmental data for the Sarney site were collected from 1986 to 1988 as part of the RI/FS by EBASCO Services under contract to US EPA. Results indicate extensive contamination within the areas identified as previous chemical waste disposal locations. On-site sampling locations are in areas on the Sarney property itself. Cleaver Swamp and its drainages will be considered as off-site locations.
A summary of the environmental contamination data collected for the Sarney Property site is presented in Appendix B. The listing of a contaminant does not necessarily mean that its presence is a public health concern. Contaminants selected for further evaluation are identified and evaluated in subsequent sections of the health assessment to determine whether exposure to them has public health significance. When selected for further evaluation in one medium, that contaminant will be reported in all media where it is detected. These contaminants are selected and discussed based upon the following factors:
- Concentrations of contaminants on and off the site.
- Field data quality, laboratory data quality, and sample design.
- Comparison of on-site and off-site concentrations with background concentrations.
- Comparison of on-site and off-site concentrations with public health assessment
comparison values for (1) noncarcinogenic endpoints and (2) carcinogenic endpoints.
These values include Environmental Media Evaluation Guides (EMEGs), Cancer
Risk Evaluation Guides (CREGs), drinking water standards and other relevant
- Community health concerns.
In on-site groundwater, di-n-butylphthalate, vinyl chloride, 1,2-dichloroethane, 2-butanone, trichloroethene, and toluene were detected at levels exceeding current NYS DOH standards for public drinking water supplies.
In general, on-site groundwater in the shallow aquifer was more contaminated than the bedrock groundwater; 1,2-dichloroethane was the contaminant with the highest concentration. In the overburden, the highest concentration of 1,2-dichloroethane was 380 micrograms per liter (mcg/L), while in the bedrock the highest concentration for 1,2-dichloroethane was 131 mcg/L. A post-ROD groundwater investigation is being conducted to confirm the directions of groundwater flow at the site. As part of this effort, the on-site residential well was sampled and tested for organic and inorganic contamination in March and June 1992. Results of testing indicate no contamination.
Data from test pits and soil borings indicate that sub-surface soils are contaminated with VOCs at levels greater than 6,000 milligrams per kilogram (mg/kg) in the areas where chemical disposal occurred. Significant contaminants found in on-site soils include naphthalene, 2-methylnaphthalene, di-n-butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate, 2-butanone, trichloroethene, 4-methyl-2-pentanone, and toluene. Results of the soil vapor study confirmed these results with high readings for toluene and trichloroethene in soils at the chemical disposal areas.
Environmental data from off-site locations consist of sampling from the nearby residential wells and Cleaver Swamp and its drainages. NYS DOH has collected the most recent VOC samples from residential wells. Surface water, sediment and residential well samples were collected by US EPA as part of the RI/FS. A summary of off-site environmental contamination is presented in Table 2.
Groundwater contaminants have been detected in off-site residential wells to the east of the site as well as the on-site Sarney well. All residential wells in the area draw groundwater from within the bedrock. Additional data were collected subsequent to the RI by NYS DOH and DC DOH, due to the inadequacy of the residential well data in the RI/FS report. NYS DOH results indicate contamination of the bedrock aquifer with 1,1-dichloroethane to the east and south of the site. The concentrations detected were about 2 mcg/L in well water from three residences. As part of the post-ROD groundwater investigation, off-site private drinking water supply wells were sampled and tested for contamination in March and June 1992. The results showed contamination in two wells with trichloroethene and 1,2-dichloroethane detected below 1 mcg/L and at 2 mcg/L, respectively. In June 1992, NYS DOH sampled and tested two residential wells. One well contained cis-1,2-dichloroethene and trichloroethene at about 0.5 mcg/L each. Other contaminants detected in 1986 and 1989 US EPA samples in off-site wells are di-n-butylphthalate, carbon disulfide, 1,2-dichloro-ethane, trichloroethene, cis-1,2-dichloroethene, styrene and lead.
Surface water and sediment samples collected from Cleaver Swamp were slightly contaminated with a variety of organic compounds, typical concentrations were less than 1 mcg/L, except for vinyl chloride which was found in one sample at 68 mcg/L. The analytical result showing vinyl chloride at 68 mcg/L in a surface water sample is unusual and unexpected given the chemical's high volatility. An elevated concentration of arsenic was detected in one surface water sample. The presence of these two compounds is suspect and may not be representative of surface water quality.
In preparing this public health assessment, NYS DOH relied on the information provided in the referenced documents and assumed that adequate quality control measures were followed with regard to chain of custody, laboratory procedures, and data reporting. The analyses and conclusions in this public health assessment are valid only if the referenced information is complete.
Samples collected by DC DOH and analyzed by NYS DOH were subject to NYS DOH QA/QC procedures. Analytical techniques followed US EPA methodology as adapted by the NYS DOH Wadsworth Center for Laboratories and Research. Analytical results subsequently passed QA/QC review.
Residential well data collected by US EPA for the RI/FS had QA/QC problems. The distilled water used for preparing trip blanks was found to be contaminated with 1,2-dichloroethane. Because of the trip blank contamination with this compound, US EPA adjusted the detection limit of 1,2-dichloroethane for these samples; because of the adjusted higher detection limit, the number of samples in which this compound was originally detected dropped from ten to one.
Vinyl chloride was detected in a single surface water sample at 68 mcg/L. Even though this result passed US EPA QA/QC review, this result is unlikely. Because of its relatively high vapor pressure, vinyl chloride would not remain in surface water for any long period since it would evaporate into the atmosphere. Additional sampling in the Cleaver Swamp or the other surface water bodies did not detect this compound. Groundwater and sub-surface soil samples did not detect this compound at appreciable levels. If this result is from degradation of the other chlorinated compounds present at this site, then vinyl chloride and its degradation precursors should have been detected in this and subsequent surface water samples.
No physical hazards were found at the site.
To identify possible facilities that could contribute to the environmental contamination near the Sarney site, the NYS DOH searched the 1989 Toxic Chemical Release Inventory (TRI). TRI is developed by the US EPA from the chemical release (air, water, and soil) information provided by certain industries. The TRI did not contain information on toxic chemical release in the Town of Amenia and, therefore, will not be discussed further in this public health assessment.
To determine whether nearby residents and persons on-site are exposed to contaminants migrating from the site, an evaluation was made of the environmental and human components that lead to human exposure. The pathways analysis consists of five elements: a source of contamination, transport through an environmental medium, a point of exposure, a route of human exposure, and an exposed population.
An exposure pathway is categorized as a completed or potential exposure pathway if the exposure pathway cannot be eliminated. A completed exposure pathway occurs when the five elements of an exposure pathway link the contaminated source to a receptor population. Should a completed exposure pathway exist in the past, present, or future, the population is considered exposed. A potential exposure pathway exists when one or more of the five elements is missing, or if modeling is performed to replace real sampling data. Potential pathways indicate that exposure to a contaminant could have occurred in the past, could be occurring now, or could occur in the future. An exposure pathway can be eliminated if at least one of the five elements is missing and will never be present. The discussion that follows incorporates only those pathways that are important and relevant to the site.
Groundwater Exposure Pathways
There is a completed exposure pathway for the past, present, and future ingestion of contaminated groundwater at this site. On-site monitoring wells in both the shallow and deep aquifers have confirmed the presence of several VOCs at levels which exceed the current NYS or Federal MCLs for drinking water. Residential groundwater wells to the south and east of the site are contaminated with similar contaminants that have been found in the on-site groundwater monitoring wells. Off-site migration of contaminated groundwater is likely, and may have been occurring for 23 years. The number of bedrock monitoring wells installed as part of the environmental investigations at the site is limited. Therefore, the extent and direction of contaminated groundwater migration can not be determined reliably. The areas surrounding the Sarney Property are entirely dependent on groundwater wells as a source of drinking water. Fourteen wells have been sampled and at present three residential wells have been found to be contaminated with the remaining eleven wells at risk for future contamination. To date, however, contaminants have not been found above health based standards.
In addition to ingestion exposures from contaminated groundwater there is also the potential for inhalation exposure from VOCs volatilizing from contaminated groundwater. The potential for dermal contact exposure to contaminated groundwater is also present from the use of contaminated groundwater.
Soil Exposure Pathways
The soil exposure pathway at the site has been deemed a potential exposure pathway for ingestion and dermal contact with contaminated soils.
On-site subsurface soils in the areas of chemical disposal are highly contaminated with toluene, 4-methyl-2-pentanone, 2-butanone, and trichloroethene present at levels from 220 to 14,000 milligrams per kilogram. In the event that these soils are disturbed or excavated, there is a potential for dermal and inhalation exposures to humans present on-site. These exposures could affect present and future residents of the property or those involved in site remediation or investigations. In addition, if soils are disturbed, the VOC concentrations in the soils are high enough to pose an off-site inhalation exposure to residents located directly south of the site through volatilization.
Highly contaminated soils and buried drums are present at several locations at the site. Any proposed remediation of this site will remove the remaining buried drums and the contaminated soils. Potential exposures to these contaminated soils could occur through direct contact and ingestion. This would be especially of concern if the soils are disturbed. Future residential development of the site would result in potential exposures to any remaining contaminated soils through direct contact and ingestion. In addition, future residents may be exposed through contaminated soil vapor migration into basements. Such exposures are unlikely since the areas with contaminated groundwater are in areas of the site which would not be conducive to future building.
Surface Water Exposure Pathways
Discharge of groundwater to the on-site and off-site surface water bodies, the on-site pond and Cleaver Swamp, could result from contaminants migrating to these surface water bodies from the shallow groundwater aquifer. Potential exposures from direct contact with and ingestion of contaminated surface water would result to people using the water bodies for recreational uses.
Table 3 summarizes the potential human exposures associated with the Sarney site.
- Past and present ingestion, dermal and inhalation exposure to organic
contaminants and metals in off-site private residential wells.
To date fourteen nearby private drinking water wells in the Town of Amenia in Dutchess County have been tested, three of which are currently contaminated with low levels of organic chemicals and lead. The extent of contamination in the past is not known but the contamination may have been occurring for 25 years and has been of community concern. Levels of organic contaminants found in these wells, except for some unconfirmed results for styrene (up to 9 mcg/L), have not exceeded New York State drinking water standards. Chronic exposure to chemicals in drinking water are possible by ingestion, dermal and inhalation exposures from water uses such as showering, bathing and cooking. Although exposures vary depending on individual life-styles, each of these exposure routes contributes to the overall intake and thus increases the potential for chronic health effects.
Styrene, 1,1-dichloroethane, 1,2-dichloroethane, and trichloroethene have caused cancer in laboratory animals exposed to high levels over their lifetimes (ATSDR, 1990f, 1990c, 1989a, 1989c). Chemicals that cause cancer in laboratory animals may also increase the risk of cancers in humans who are exposed to lower levels over long periods of time. Whether or not these chemicals cause cancer in humans is not known. Based on the results of animal studies and the limited sampling of private wells, we estimate that persons exposed to contaminated drinking water may have a low increased risk of developing cancer. Toxicological data are inadequate to assess the carcinogenic potential of di-n-butylphthalate, cis-1,2- dichloroethene and carbon disulfide (ATSDR, 1990b, 1990d and US EPA, 1990).
1,1-Dichloroethane, 1,2-dichloroethane, cis-1,2-dichloro- ethene, and trichloroethene produce a variety of noncarcinogenic toxicities (primarily liver, kidney and nervous system effects). Styrene can damage red blood cells and the liver. Di-n-butylphthalate and carbon disulfide have been associated with adverse effects on reproduction and fetal development. Each of these chemicals is known to cause adverse effects at exposure levels several orders of magnitude greater than those found in drinking water. Chemicals that cause effects in humans and/or animals after high levels of exposure may also pose a risk to humans who are exposed to lower levels over long periods of time. Although the risks of noncarcinogenic effects aren't completely understood, the existing data suggest they are minimal.
Low levels of lead in residential drinking water may be caused by household plumbing. Chronic exposure to elevated lead levels is predominantly associated with neurological and hematological effects (ATSDR, 1990e). At high exposure levels, lead can cause kidney damage, gastrointestinal distress and reproductive effects including abortion and damage to the male reproductive system. The developing fetus and young children are particularly sensitive to lead-induced neurological effects with symptoms ranging from delayed mental development and behavioral effects at low blood lead levels to frank ataxia, stupor, coma and convulsions at high blood levels. Chronic exposure to drinking water contaminated with lead at the highest concentration (5.4 mcg/L) found in off-site groundwater would pose a minimal increased risk of adverse health effects.
- Potential ingestion, dermal and inhalation exposure to contaminants
in private residential wells as a result of contaminated plume migration.
As indicated in Table 1, on-site groundwater is contaminated with organic chemicals at concentrations that exceed New York State drinking water standards. There is a potential for ingestion, dermal and inhalation exposure to these contaminants in residential private wells from contaminant plume migration.
Vinyl chloride is a known human carcinogen (ATSDR, 1989). 1,2-Dichloroethane and trichloroethene cause cancer in laboratory animals exposed to high levels over their lifetime (ATSDR, 1989a, 1989c). Chemicals that cause cancer in laboratory animals may also increase the risk of cancer in humans who are exposed to lower levels over long periods. Chronic exposure to the highest levels of vinyl chloride (14 mcg/L) and 1,2-dichloroethane (380 mcg/L) found in on-site groundwater would pose a high increased cancer risk over a lifetime of exposure; chronic exposure to trichloroethene (10.7 mcg/L) would pose a low increased cancer risk. Toxicological data are inadequate to assess the carcinogenic potential of 2-butanone, di-n-butylphthalate and toluene (ATSDR, 1990a, 1990b, 1989b).
1,2-Dichloroethane, trichloroethene, toluene and vinyl chloride produce a variety of noncarcinogenic toxicities (primarily liver, kidney and nervous system effects). Di-n-butylphthalate has been associated with adverse effects on reproductive and fetal development (ATSDR, 1990b). 2-butanone produces adverse liver, kidney and central nervous system effects (ATSDR, 1990a). These chemicals produce their effects at exposures several orders of magnitude greater than potential exposure from on-site groundwater. Chemicals that cause effects in humans and/or animals after high levels of exposure may also pose a risk to humans who are exposed to lower levels over long periods of time. Although the risks of noncarcinogenic effects from these potential exposures aren't completely understood, the existing data suggest that they would be low.
The health risks of exposure to lead have already been discussed (see #1 above). Chronic exposure to drinking water contaminated with lead at concentrations found in on-site groundwater (up to 18 mcg/L) would pose a moderate risk of adverse health effects, particularly for the developing fetus, infants and young children.
- Potential inhalation, dermal and ingestion exposure of persons engaged
in on-site clean-up activities and nearby residents to contaminated soil.
Subsurface soils on-site are contaminated with organic chemicals and metals. Persons engaged in clean-up (remediation activities) or other activities which expose contaminated soil could be at risk of adverse health effects. Use of appropriate dust suppression methods and monitoring of ambient air contaminated with organic vapors during clean-up would minimize any low level increased risk to nearby residents.
- Potential ingestion, dermal and inhalation exposure of persons engaged
in recreational activities in adjacent streams and wetlands.
Off-site surface water contains metals and may be contaminated with vinyl chloride which would present a public health threat, especially to children who could play in these areas on a frequent basis.
- Potential inhalation exposure of volatile organic compounds in indoor
air due to migration of soil vapors into nearby structures.
Adequate data are not available to assess the toxicological implications of this potential exposure pathway. However, some data suggest that trichloroethene and toluene could pose a public health threat. These volatile organic compounds were detected in on-site soil gas.
No health outcome data have been generated for this site and no site specific studies have been done. Currently there are no plans for specific studies because exposure to contaminants in drinking water is low. In addition, there have been no community health concerns which indicate any adverse health outcomes. The situation will be reevaluated if new data become available.
We have addressed each of the community concerns about health as follows:
- The health risks associated with leaking drums buried on the site.
Contaminated soils and drummed wastes buried on site may result in potential human exposures through two mechanisms: as a continuing source of groundwater contamination and through direct contact, ingestion, and vapor emission. Of these two, the effect of the contaminated soils as a source of present and future groundwater contamination has the most serious effect on public health through potential exposure to contaminated groundwater. As part of the remedial activity proposed for this site, all buried drums and contaminated soils surrounding the drums will be removed from the site.
- The possibility that residents would not be notified of well water sampling
results, especially if contaminants were detected.
The US EPA, DC DOH and NYS DOH are performing the residential well monitoring and will ensure that residents receive prompt notification of sample results. NYS DOH will provide an explanation of the data's significance to public health.
- The suitability of the site for agricultural use after the site has been
The proposed clean up of the site will remove any contamination which would pose a hazard to the use of this site for agriculture.
- The safety of using well water that is contaminated with trace levels of
To date, all wells tested have not exhibited any contamination that exceeds NYS DOH drinking water standards as they apply to public water supplies. The trace contamination detected in several wells does not pose a health hazard to those using the water for drinking and other household uses.
- The possible exposure hazard of emissions from proposed on-site treatment
facilitates to the nearby residents.
All remedial activities at the site will be conducted under a community health and safety plan. This will provide for air monitoring at the site to insure that contaminants are not released by the treatment systems or other activities at the site at levels that could pose a health concern.