PETITIONED PUBLIC HEALTH ASSESSMENT
YAWORSKI WASTE LAGOON
(ALIASES: YAWORSKI DUMP AND PACKER ROAD LANDFILL)
CANTERBURY, WINDHAM COUNTY, CONNECTICUT
The Agency for Toxic Substances and Disease Registry (ATSDR) was asked by residents of Canterbury, Connecticut to evaluate potential exposure to hazardous substances in the ground water identified at the Yaworski Waste Lagoon Superfund Site and the Yaworski Landfill sites. Residents were concerned about cancer, respiratory ailments, and drinking water safety. The Yaworski Waste Lagoon Superfund Site, located on Packer Road in Canterbury Township, was added to the United States Environmental Protection Agency (EPA) Superfund National Priorities List (NPL) in 1984 and is currently under the EPA jurisdiction. The Yaworski Landfill (also called the Yaworski Dump or Packer Road Landfill) site consists of 44 acres located approximately 2,000 feet from the lagoon and is regulated by the Connecticut Department of Environmental Protection (CT DEP). ATSDR reviewed groundwater sampling data provided by the EPA for the Yaworski Waste Lagoon Superfund Site and by CTDEP for the Yaworski Landfill, as well as private well data. Groundwater beneath the Yaworski Waste Lagoon Superfund Site and Yaworski Landfill is contaminated with volatile organic compounds (VOCs) and metals. Two contaminated groundwater plumes, one from the lagoon and one from the landfill have migrated beneath the river and were detected in monitoring wells located on the opposite bank of the Quinebaug River. The aquifer below the lagoon and landfill is not currently used for human consumption. However, contamination in the groundwater beneath the lagoon and landfill has migrated beneath the river and represents a potential health hazard if the groundwater is used as a future source of potable water. Therefore, the use of this groundwater aquifer for human consumption should be restricted and tested prior to future land development.
The Agency for Toxic Substances and Disease Registry (ATSDR) was petitioned by residents of Canterbury, Connecticut to determine if contaminated groundwater releases from the Yaworski Waste Lagoon Superfund Site and the Yaworski Landfill represent a public health hazard to the community. Petitioners expressed concerns about cancer, respiratory ailments, and drinking water safety. Residents formed a community group, the People's Rights in a Clean Environment (PRICE) to present their concerns. In this health assessment, ATSDR will review the groundwater data available from sampling conducted at the Yaworski Waste Lagoon Superfund Site, private wells, and the Yaworski Landfill and will make recommendations to address health concerns.
The Yaworski Waste Lagoon Superfund Site is situated on five acres within a bend of the Quinebaug River, between Route 169 and Packer Road in Canterbury Township, Windham County, Connecticut (Figure 1, Appendix A). It is located approximately 2,000 feet from the Yaworski Landfill. Industrial waste including solvents, paints, textile dyes, acids, resins, and other debris were dumped into the lagoon from 1950 to 1973 (1, 2). Periodically, flammable waste was burned at the site until 1965. Dumping at the lagoon was stopped in 1973 and the lagoon was closed in 1982. This site was added to the United States Environmental Protection Agency (USEPA) Superfund National Priorities List (NPL) in 1984 and is currently under the US EPA jurisdiction (CTD009774969). After investigating the site, EPA issued a Record of Decision in September 1988 (3) and a Consent Decree for the site was entered in February 1990 (4).
In 1976, monitoring wells were placed adjacent to the lagoon to determine the extent of groundwater contamination (Figure 2, Appendix A). Additional monitoring wells were installed in 1991 and 1992 (5). In 1990, the dike surrounding the lagoon was improved and a multi-layer cap was completed to reduce migration of contaminants into wetlands, the river flood plain, and groundwater. Quarterly monitoring of groundwater began in March 1993 but in April 2000 monitoring was reduced to three times a year. Alternate concentration limits (ACLs) were finalized in September 2000, establishing a numerical limit of the amount of contamination that can exist in groundwater without endangering human health and the environment (5).
ATSDR released a Public Health Assessment for the Yaworski Waste Lagoon Superfund Site in April 1988 (6). Based on a review of existing groundwater data from 25 on-site monitoring wells, contamination levels of volatile organic and inorganic compounds in groundwater on the site posed a future threat to human health if the groundwater would be used as a source of potable water. Surface water from the site may be contributing metals (cadmium, chromium(VI), copper, zinc, and lead) to the river and wetland areas, but not at concentrations that would pose a human health risk. The report concluded that leachate seepage and sediments and wetland surface water and sediments did not pose a threat to human health. Bioaccumulation of contaminants in consumed fish and agricultural crops harvested nearby represented a data gap (6). A site review and update of the Yaworski Waste Lagoon Superfund Site was released by ATSDR in September 1993 (7). During a visit in October 1992, the site was observed to be fenced and the cap maintained. In 1993, groundwater sampling results of a well sampled across the river from the lagoon showed that benzene levels were above EPA's drinking water standard and that the Quinebaug River did not act as a barrier to prevent contamination from crossing the river (7, 17). Although this aquifer is not a source of drinking water for residents, EPA is currently working with property owners to restrict groundwater use across the river from the lagoon.
The Yaworski Landfill (also called the Yaworski Dump or Packer Road Landfill) site consists of 44 acres located in Canterbury Township, Windham County, eastern Connecticut and is owned by Yaworski Incorporated. The landfill is not listed as an EPA NPL site but is regulated under State authority. The landfill accepted waste from 1950 to 1995 under a permit by the Connecticut Department of Environmental Protection (CT DEP) (8). Materials accepted for disposal included municipal, residential, and solid waste. The landfill lies within the flood plain of the Quinebaug River and the river borders the site on the north, south, and west sides (Figure 1, Appendix A).
Yaworski Landfill currently consists of three sections; the closed landfill, bulky waste landfill, and the former "active" landfill (Figure 3, Appendix A) (9). The closed landfill is approximately eight acres in size and located east of Packer Road. The landfill opened in 1950, accepting an unknown volume of residential and municipal waste. This section of the landfill was closed and capped with an earthen cover in 1970. Opened in 1960, the bulky waste landfill, located east of Packer Road and south of the closed landfill, consists of approximately four acres (9). Solid waste such as wood, brush, stumps, and other demolition debris was deposited in this area. It is reported that approximately 20 feet of waste is buried in this area. The former "active" landfill was opened in 1950 and is located west of Packer Road (9). This 32 acre section accepted mixed solid waste under a CT DEP permit. The western portion of the former "active" landfill is closed (May 1995) and covered with an earthen cover material. The former "active" landfill is surrounded by the Quinebaug River on the north, west, and southwest borders, and by residences and light industry on the east and southeast borders. Soil cover material from the Gallup's Quarry site (CTD108960972), another NPL site located approximately three miles to the east in Plainfield Connecticut, was reported to have been placed in this section of the landfill (10).
There are 16 monitoring wells (14 overburden, 2 bedrock) located in the former "active" section (Figure 2). The depth below land surface to groundwater measured in monitoring wells is between 5.0 to 45.5 feet. Groundwater is between 5.0 top 30.0 feet below ground surface in the closed section of the landfill. Sections of the bulky waste landfill may reach the water table due to the depth and the proximity of the landfill material to the adjoining wetland (9, 11, 12, 13, 14). Groundwater flow (in overburden) in the areas of the closed and bulky waste landfills appears to be to the west, toward the Quinebaug River. Groundwater flow in the area of the former "active" landfill is generally to the west but shifts slightly to the north and south, toward the Quinebaug River (13, 14, 15). Surface water runs off from the former "active" and most of the bulky waste landfills to the Quinebaug River, while most surface water in the closed landfill is absorbed into the ground. There are no surface water intakes for drinking water within 15-miles downstream from the Yaworski Landfill (13, 14, 15).
The area surrounding the lagoon and landfill is primarily rural/residential and agricultural. The nearest residence and private drinking water well (most private wells are screened in bedrock) is located within 0.25 miles of the property (9, 16). Approximately 12,878 people obtain drinking water from groundwater sources located within four miles of the Packer Road Landfill and approximately 7,259 are served by private wells (9, 16).
Residents live within one-half mile of the site with the nearest residence approximately 200 to 300 feet from the active landfill. Residents are concerned about exposure to potentially contaminated private well water resulting from activities at the lagoon and landfill, a perceived increased incidence of cancer, respiratory ailments, and drinking water safety.
ATSDR obtains the community's concerns, and other medical, toxicological, demographic, and environmental factors that may affect the health of a community exposed to hazardous substances. To determine if health effects are likely to occur within the community, ATSDR health professionals consider the toxicity of the contaminant, the concentration (how much), the time of exposure (how long), and how the chemical gets into the body (breathing, eating, drinking, or skin contact). In addition, other factors are considered; occupation, personal habits, age, nutritional status, general health, and genetics. These factors affect how a contaminant is absorbed, distributed, metabolized, and eliminated from the body. Contaminants are evaluated in a health assessment to determine whether exposure to them has public health significance. ATSDR selects and compares on- and off-site concentrations of contaminants with ATSDR comparison values for non-carcinogenic and carcinogenic effects. Comparison values are concentrations of contaminants in specific environmental media (air, soil, drinking water) that are not expected to produce an adverse health effect in people who are exposed. These values are used only as screening values, listing a contaminant in a table of "chemicals of concern" does not mean that it will necessarily cause adverse health effects if exposure occurs at that specified concentration. When the concentration of a contaminant detected on or off the site is above the comparison value it is further evaluated to determine the potential for adverse health effects. The focus of the evaluation is on health effects that could plausibly result from exposures to site related contaminants. ATSDR considers both adults and children when developing comparison values. The potential health effect on children is considered separately since in certain situations children may be more sensitive and more exposed to contaminants. Finally, ATSDR presents its conclusions and recommends appropriate actions.
The meandering and fluctuating water level of the Quinebaug River and the three major zones of permeability in the aquifer make the groundwater flow system identified underneath and surrounding the Yaworski Waste Lagoon Superfund Site complex. The three groundwater flow zones defined are the shallow (15-20 feet) (Figure 4, Appendix A), intermediate (30-50 feet) (Figure 5, Appendix A) and the deep (>50 feet) (Figure 6, Appendix A) (17). Metcalf and Eddy collected groundwater samples for EPA (18, 19) at monitoring wells on the Yaworski Waste Lagoon Superfund Site, offsite near the landfill, and across the Quinebaug River. Samples taken during this pre-design investigation were used to better characterize and delineate the migration of the contaminated plume down-gradient of the lagoon and across the river. Groundwater samples were analyzed for volatile organic compounds (VOCs), semivolatile organic compounds (SVOCs), pesticides, polychlorinated biphenyls (PCBs), dioxins, and metals.
Groundwater samples collected from September 1992 to December 1998 were reviewed by ATSDR for identification of contaminants that potentially represent a public health hazard (Table 1, Appendix B). This groundwater is not currently being used as a potable water source. Over 20 different VOCs (aromatic volatile organic compounds, chlorinated volatile organic compounds, and ketones) were detected in the groundwater samples taken at this site (19). BTEX (benzene, toluene, ethylbenzene, and xylene), chlorinated VOCs (chloroethane, 1,1-dichloroethane [1,1-DCA], 1,1,2-trichloroethane [1,1,2-TCA], and trichloromethane [TCE]), tetrahydrofuran (THF), and ketones (acetone, 4-methyl-2-pentanone [MIBK] and 2-butanone [MEK]) were detected in the lagoon monitoring wells. VOCs were found more often in elevated concentrations around the perimeter of the lagoon at the point of compliance, well clusters B, C, and G (Figure 7, Appendix A; Table 1, Appendix B). The highest concentrations of VOCs at well clusters C and G were found in the shallow flow zone (Figure 4) and the river/groundwater interface, adjacent to the river side of the lagoon. Decreasing concentrations were detected in the intermediate (Figure 5) and deep flow zones (Figure 6) at well clusters C and G. BTEX was predominant in the intermediate flow zone screened directly below the sludge layer. Light non-aqueous phase liquid (floating product) represents a secondary source of VOC contamination found in a shallow flow zone on top of the lagoon and at the end of the southeast corner of the lagoon. The highest concentration of contaminants were found in monitoring well designated Cs, near the lagoon (Figure 7, Appendix A; Table 1, Appendix A). BTEX was substantially higher than other contaminants such as chlorinated VOCs and ketones. They were the predominant contaminants detected in the vicinity and down-gradient of the lagoon in terms of frequency of detection and concentration. Cluster B monitoring wells demonstrated that VOC concentrations were lowest in the shallow zone, increasing sharply in concentration in the intermediate zone, then decreasing in the deep flow zone.
VOCs (ethylbenzene, xylene, THF, and two chlorinated VOCs) were occasionally detected in well clusters D, F, and I located south and down-gradient from the lagoon. In 1998, VOCs were detected in well cluster J, located across the river and southwest of well clusters I and F, in the intermediate and deep flow zones. VOCs were detected in the intermediate and deep flow zones at well cluster N, indicating contamination south of and across the river from the lagoon (Table 1, Appendix B). Benzene (6.4-20 ppb) was detected above the maximum contaminant level (MCL 5 ug/L) in the groundwater well Ni, located south of and on the opposite side of the river from the lagoon (Table 1, Appendix B). Bis (2-ethylhexyl) phthalate was detected at well cluster H (Hs=59 ppb, Hi=8 ppb) and well cluster N (Ni=6-28 ppb, Nd (8-38 ppb). The maximum concentrations of 1,1,2,2-tetrachloroethane (44 ppb), 1,2-dibromo-3-chloropropane (74 ppb), 4-isopropyltoluene (1.2 ppb), and isopropylbenzene ( 24 ppb) were detected in well Ni across the river (Table 1, Appendix B). Lead (5.9 ppb) and cadmium (5.6 ppb) were detected in well Nd, and lead (8.7 ppb) was detected in well Ns, above the action level (MCL action level 5 ppb). 1,2-dibromoethane (0.9 ppb) was detected in well Hd located across the river, west of the lagoon. Hexachlorobutadine (1.4 ppb) and trichloroethene (180 ppb) were detected in well Ki, located south across the river from the lagoon and west of the landfill. Lead was detected in well Pi (5.6 ppb) and well Pd (15.9 ppb), located across the river from the landfill.
Metals were detected throughout the Yaworski Waste Lagoon Superfund Site including; barium, manganese, cadmium, magnesium, cobalt, copper, nickel, and vanadium. In general, heavy metals were found to be associated with wells having higher VOC contamination. The most recent groundwater sampling data indicates that the VOC plume from the lagoon is migrating south under the river through the intermediate and deep flow zones. Well cluster N, across the river contained high concentrations of BTEX compared to concentrations of chlorinated VOCs (17).
In the mid 1970s, a groundwater monitoring program was established in the former "active" landfill. Groundwater samples have been collected from 16 monitoring wells (13, 14) (Figures 2 and 3, Appendix A) located around the former "active" landfill from the 1980's to present, approximately 3-4 times per year. The depth to ground water at this site is from 5 to 45.5 feet below the land surface (9). ATSDR reviewed the monitoring well (Table 2, Appendix B), surface water (Table 3, Appendix B), and private well (Table 4, Appendix B) sampling data to evaluate groundwater contamination and potential public health implications (11, 12, 13, 14).
Volatile organic compounds (BTEX, chlorinated volatile organic compounds, and ketones) were detected in the groundwater samples obtained from this site (Table 2, Appendix B). While chlorinated VOCs represent the highest concentrations and most frequently detected contaminants, THF, ketones, and BTEX have also been detected in the past and currently. Elevated concentrations of ammonia, arsenic, cadmium, and lead have also been detected in groundwater samples from monitoring wells. The maximum concentrations of potential contaminants of concern have been detected in monitoring wells #1, well cluster #14, and #3, located on the western side of the landfill closest to the meander of the Quinebaug River (Figures 2 and 3, Appendix A, Table 2, Appendix B). Maximum concentrations of benzene (78 ppb), chlorobenzene (150 ppb), 1,4-dichlorobenzene (150 ppb), dichlorobenzene (147 ppb), 1,1-dichloroethane (75 ppb), arsenic (64 ppb), cadmium (52 ppb), and lead (518 ppb) were detected in monitoring well #1, located on the northern section of the former "active" landfill, near the river. Chlorinated VOCs were detected in the well cluster #14, on the western side of the landfill. Sampling data indicates that the plume of contamination is moving toward the river, down-gradient from private wells.
Chlorinated VOCs, aromatic VOCs (BTEX), and THF were detected in monitoring wells located west, across the river from the Yaworski Landfill. TCE and 1,2-DCE were detected at the highest concentrations in the shallow flow-zone wells. In general, chlorinated VOCs and THF were detected at higher concentrations in the monitoring wells at the Yaworski landfill than BTEX. VOCs were detected in water samples taken from all three flow-zones at well cluster L, located west and down-gradient from the landfill near the river. The concentration of chlorinated VOCs were higher than BTEX concentrations, similar to the results found in monitoring well near the landfill. Based on the groundwater sampling results, the leachate plume from the landfill appears to be moving mostly west-southwest, down-gradient from domestic wells, located near the site. Although monitoring well #1, located just north of the former "active" landfill section and within a bend in the river, has been affected with high concentrations of chlorinated VOCs (Table 2, Appendix B).
Surface water data (Table 3, Appendix B) collected from 1990 to 1997 do not show contaminants at levels of concern and are not currently impacting the water quality of the Quinebaug River (9). Dioxins, furans, and some heavy metals have been detected in surface water and sediment, but not at concentrations that would pose an increase risk of exposure to contaminants (6, 7).
According to a 1991 report (14), approximately 12,878 people obtain their drinking water from groundwater sources within four miles of the Yaworski Landfill and Yaworski Lagoon Superfund Site. Private wells within a half-mile radius of the site appear to be up-gradient from the groundwater contaminant plume. Thirty private drinking water wells have been sampled almost quarterly from 1990 to 1997 and analyzed for VOCs and metals as part of landfill monitoring requirements (Table 4, Appendix B). Most of the contaminants detected in these private well samples were below ATSDR health comparison values. Tetrachloroethylene (0.22- 1.5 ppb), vinyl chloride (0.8-1.6 ppb), and thallium (5.4 ppb) were detected in one well (DW-17A) located at the Yaworski Truck Display Building on site in 1992-3 (Table 4, Appendix B). 1-1-dichloroethane (0.7 ppb, 0.9 ppb) was detected in 2 of 146 samples taken from well DW-17C taken at a residence on Packer Road. The maximum concentration (0.9 ppb) is above the CREG but not above the chronic EMEG for a child or adult. Cadmium (10 ppb, MCL 5 ppb) and nitrate (23,000 ppb, MCL 10,000 ppb) were detected above comparison values only once in a private well (DW-19) located on Packer Road. Health effects would not likely result from a one-time exposure of 10 ppb, a concentration two times the MCL (5 ppb). Methylene chloride was detected only during one sampling event in a private well (DW-16). Lead was detected above the EPA action level of 15 ppb in well samples taken from four private drinking water wells. The concentrations detected in these wells (only one sampling time out of seven) were 18 ppb at well DW-19 (10/3/90), 90 ppb in DW-16 (7/3/90), 100 ppb in DW-14 (7/3/90), and 210 ppb in well DW-15 (7/7/90). The fact that these elevated levels were detected in only one out of seven sampling events suggests that these measurements reflected something other than the condition of the aquifer being tapped (e.g. a plumbing effect).
Discussion of Community Health Concerns
Citizens were concerned about a perceived increase in the incidence of cancer within their community. The CT DHP evaluated cancer rates in Canterbury, Plainfield, and two other surrounding towns in Connecticut compared to expected rates for cancers occurring within populations of similar size in the United States. Cancer incidence rates for reported cancer cases occurring over a twenty year period (1971 to 1990) were obtained. The analysis demonstrated that no differences were observed in the number of cancer cases reported in the populations in Connecticut compared to the number of cases that would be expected (7). Therefore, no increase from the expected cancer rates were observed.
1. The Yaworski Waste Lagoon Superfund Site and Yaworski Landfill sites are not apparent health hazards in the past or present because the aquifer below the sites is not used for human consumption. Identified private wells are up-gradient of the contaminant plumes. Connecticut has classified this aquifer GB or for industrial use only and not for direct human consumption without prior treatment.
2. Groundwater beneath the Yaworski Waste Lagoon Superfund and Yaworski Landfill sites is contaminated with volatile organic compounds and metals above health comparison values for drinking water and these sites represent a potential health hazard if this groundwater is used for potable water in the future.
3. Contaminants were detected in some private wells near the landfill, but generally not at levels that would result in adverse health effects. The elevated levels of lead (up to 230 ppb) detected once (out of 7 sampling events) in four different private wells apparently reflect a source unrelated to aquifer conditions.
4. Groundwater beneath the Yaworski Waste Lagoon Superfund and Yaworski Landfill sites is contaminated with volatile organic compounds and metals above health comparison values for drinking water. This contaminated groundwater has migrated off-site and groundwater on the other side of the Quinebaug river is contaminated.
5. From previous sampling reports, the potential for exposure to contaminants in the soil, sediments, or surface water is not an apparent health hazard.
1. Continue groundwater monitoring on and off the Yaworski Waste Lagoon Superfund and Yaworski Landfill sites to determine the extent and migration of contamination.
2. ATSDR supports the continuation of groundwater use restrictions in place for the area within the meander of the Quinebaug River, including the lands identified across the river.
3. Private wells identified with intermittently elevated levels of lead believed to be unrelated to aquifer conditions should continue to be tested quarterly. ATSDR will review sampling data when it becomes available.
1. Site visits and meetings with the community, state and local health and government agencies.
2. Release of ATSDR Public Health Assessment (1988) evaluating the Yaworski Waste Lagoon Superfund Site.
3. Release of ATSDR Health Consultation (1994) evaluating Yaworski Landfill and Yaworski Waste Lagoon Superfund Site.
4. Release of ATSDR Health Assessment (1998) evaluating the Gallup's Quarry site.
5. Release of ATSDR Health Assessment (2000) evaluating the Yaworski Landfill site.
1. ATSDR will review sampling data that may become available in the future and make appropriate recommendations.
Adele M. Childress, PhD, MSPH
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Exposure Investigations and Consultation Branch
Frank Schnell, PhD, DABT
Agency for Toxic Substances and Disease Registry
Division of Health Assessment and Consultation
Exposure Investigations and Consultation Branch
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3. U.S. Environmental Protection Agency (U.S. EPA). Record of Decision for Yaworski Lagoon Site in Canterbury, Connecticut. 1988 Sep.
4. U.S. Environmental Protection Agency (U.S. EPA). Consent Decree for Yaworski Lagoon Site in Canterbury, Connecticut. 1990 Feb.
5. U.S. Environmental Protection Agency (U.S. EPA). Final Pre-Design Engineering Report, Yaworski Lagoon Superfund Site. Canterbury, Connecticut: 1999 Dec.
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11. Connecticut Department of Environmental Protection. Analytical Sample Results, Private well water supplies located near the Packer Road Landfill in Canterbury Connecticut.1992 Apr.
12. Connecticut Department of Environmental Protection. Analytical Sample Results, Private well water supplies located near the Packer Road Landfill in Canterbury Connecticut. 1992 Jul.
13. Fuss & O'Neill, Inc. Consulting Engineers. Yaworski Landfill, Ground and Surface Water Monitoring Results. Canterbury, Connecticut:1990 Nov.
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15. United States Geological Survey ( USGS). Plainfield Quadrangle. Connecticut. U.S. Geological Survey. 7.5' Series (Topographic). 1983b.
16. Fuss & O'Neill, Inc. Consulting Engineers. Map of Property Owners and Water Supplies within 1,000 feet of Expansion. plate no. 6. 1986 Dec.
17. ENSR Consulting and Engineering (ENSR). ACL Demonstration Report, Yaworski Lagoon Superfund Site. 1993 Mar.
18. Metcalf & Eddy (M&E). Final Sampling and Analysis Plan for Pre-Design Investigation-Yaworski Lagoon Superfund Site, Canterbury Township, Connecticut. Prepared for the U.S. Environmental Protection Agency. 1998 June.
19. Metcalf & Eddy (M&E) 1999. Final Pre-Design Engineering Report-Yaworski Lagoon Superfund Site, Canterbury Township, Connecticut. Prepared for the U.S. Environmental Protection Agency. 1999 Dec.