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PUBLIC HEALTH ASSESSMENT

PELHAM BAY LANDFILL
BRONX, BRONX COUNTY, NEW YORK


SUMMARY

The Pelham Bay Landfill (PBL) site is an inactive municipal solid waste landfill in Bronx County, New York. The site was used and operated by the New York City Department of Sanitation (NYC DOS)to handle waste disposal needs of the Bronx from 1963 to 1978. Landfilling stopped on December 31, 1978. During the 1980's, the nearby community expressed concerns about exposure to both on-site and off-site contaminants and the potential link to local cases of childhood leukemia, autism, and multiple sclerosis. As a result of community concerns, the Pelham Bay Task Force, which is comprised of community members, elected officials and representatives of regulatory agencies, was formed. Independent scientists were hired to review all work, including environmental studies conducted at the landfill, and are known as the Pelham Bay Science Advisory Committee (SAC). In response to community concerns, the New York City Department of Health (NYC DOH) conducted retrospective cancer epidemiology studies. The results of these studies show no evidence of an overall increase in cancer rates in the neighborhoods surrounding the PBL due to the landfill.

Based on the data and information viewed for this public health assessment, the site poses no apparent present and future public health hazard to the residents of Pelham Bay area. The completed remedial measures are operating effectively and further reduction of potential off-site migration of contaminants is expected from ongoing remediation activities.

In December 1994, an air monitoring program was initiated which coincided with construction of the landfill cap. The air monitoring program was run during the reshaping of the landfill and placement of the synthetic geomembrane liner, which was completed in November 1995. The air monitoring program did not indicate any significant exposures to the community occurred as a result of the construction of the cap. From November 1995 until the present, work has focused on placing the final grass cover on top of the synthetic membrane. In the spring of 1996, a flare became operational to burn the gases from the landfill gas collection system.

Past completed exposure pathways associated with on-site use of the Pelham Bay Landfill include: (1) incidental ingestion and dermal contact with landfill soils; (2) inhalation of fugitive dust; and (3) breathing volatile emissions from the landfill. Adults and sensitive groups, which include children and the homeless, may have been exposed in the past to levels of on-site contaminants that posed a public health hazard. These past exposures to PAHs in on-site soils could pose a low increased cancer risk to on-site workers and to those persons who ate vegetables grown in this soil. Furthermore, review of historical data concerning past site conditions indicates that noxious odors, open fissures and leachate seeps were typical observations made during on-site visits and were voiced as community complaints.

Present or potential future on-site exposures to airborne contaminants, leachate-groundwater and contaminated soils has been minimized or eliminated due to: (1) fencing, which has been maintained to restrict unauthorized entry to the site; and (2) state-of-the-art capping of the landfill. The closure of the landfill included the installation of a high density polyethylene (HDPE) geo-membrane, soil-gas collection and treatment system, leachate collection system and a soil-bentonite slurry wall. Because groundwater is not used for potable water within the local area, past, present, or future exposures to contaminated groundwater are unlikely.

In 1995, the Agency for Toxic Substances and Disease Registry (ATSDR's) Health Activities Recommendation Panel (HARP) suggested that both community and health professional education is needed. The HARP indicated that education is needed to help people understand exposure and exposure pathways.

In 1995, a federal grant from the National Association of County and City Health Officials (NACCHO) was awarded to the NYC DOH to study the Pelham Bay community's level of awareness regarding health issues related to the Pelham Bay Landfill. The purpose of the grant was to identify the health issues of greatest interest and to determine the type of information needed to address remaining concerns. A second grant was obtained to provide the information needed as identified in the survey. A one day class and literature on environmental exposure pathways was presented to the community in 1996. The effort was led by the Mount Sinai-Irving J. Selikoff Center for Occupational and Environmental Medicine and was overseen by the NYC DOH.


BACKGROUND

The NYSDOH prepared this public health assessment under a cooperative agreement with the ATSDR. ATSDR was petitioned in May 1989 to evaluate the relationship between the landfill contamination and health effects of the population surrounding the landfill. The ATSDR and NYS DOH evaluated whether the Pelham Bay Landfill poses any past, present or future health threats. We also evaluated if the remediation of the landfill is appropriate and protective of human health.

A. Site Description and History

The Pelham Bay Landfill (PBL) is an inactive 81-acre municipal waste dump at 40º51'23" latitude, 73º48'52" longitude in the Bronx, a borough of New York City, New York (Appendix A, Figure 1). The site is bordered by the Hutchinson River to the north and east, the Eastchester Bay to the east and south, the Pelham Bay Park to the southwest, and Bruckner Boulevard Extension to the northwest. The New England Thruway (I-95) is less than one-half mile west of the site. The Co-Op City housing complex is about one-half mile northwest from the site. The landfill has an elevation of 131 feet with steep slopes that rise to a nearly flat top.

Typical wastes received at the site included: residential wastes, rubbish, street dirt, construction waste and demolition debris. On May 6, 1982, a driver/dispatcher for the Hudson Oil Refining Company testified before a New York State Senate Committee on Crime, that waste oil sludges Exiting ATSDR Website, metal plating wastes, lacquer, and solvents were illegally disposed at several New York City landfills, including the Pelham Bay Landfill from 1974 to 1980 (NYS DEC 1986). The exact amount and location of wastes disposed of was not described. The contaminants identified during subsequent hearings include cyanide, heavy metals, volatile and semi-volatile organic compounds.

The NYS DEC listed the PBL in the New York State Registry of Inactive Hazardous Waste Sites as a Class 3 in 1983. A Class 3 hazardous waste site means the site is not considered a significant threat to public health. In 1984, the classification was changed to a Class 2a, which means there is insufficient data to determine the site's classification. In 1987, based on information provided to the NYS DEC, the site was reclassified to Class 2, which means the site is considered a significant threat to the environment or public health. With this change in the classification of the site, New York City qualified for funds from New York State to remediate the site.

During the 1980's, the nearby community expressed concerns about exposure to both on-site and off-site contaminants and the potential link to local cases of childhood leukemia, autism, and multiple sclerosis. In response to these concerns area residents formed the Pelham Bay Task Force which is comprised of community members, elected officials and representatives of regulatory agencies. Local citizens were provided funds by New York City Department of Environmental Protection (NYC DEP) to employ independent scientists to review all work, including environmental studies conducted at the landfill. The group of independent scientists are known as the Pelham Bay Landfill Science Advisory Committee (SAC).

In April of 1990, the NYS DEC and New York City entered into a Consent Order (Index Number: 2-03-001) requiring that a remedial investigation and feasibility study (RI/FS) be conducted in accordance with United States Environmental Protection Agency RI/FS guidance documents and procedures (NYS DEC, 1993). The RI/FS evaluated the nature and extent of contamination at PBL. The 1990 Order of Consent updated the 1985 order ( Index Number: 2-0956) to address the funding, site investigation, and remediation requirements of Title 3 of the Environmental Quality Bond Act. The RI/FS was completed in June of 1993 (Woodward-Clyde Consultants, 1993). A supplemental RI, which examined off-site soils, was also completed in June 1993 by Woodward-Clyde Consultants, Inc. (WCCI). A supplemental RI specifically addressed whether leachate and the seeps from the landfill contaminated off-site soils.

In 1990, a lawsuit was filed by the New York Coastal Fisherman's Association against New York City to take measures to prevent Pelham Bay Landfill leachate from entering Eastchester Bay. The basis of the lawsuit was that leachate was disposed directly from the landfill into Eastchester Bay via a sewer outfall, which violated the Clean Water Act. Other sources of leachate from the landfill included shoreline seeps.

As a result of this litigation, a permanent injunction was issued requiring New York City to take measures to prevent leachate from entering Eastchester Bay. The injunction resulted in the installation of the "150 Day" leachate collection system consisting of five tanks which each have a 20,000 gallon storage capacity. Five interceptor wells were installed near the site perimeter in order to prevent landfill leachate from seeping into Eastchester Bay. Using the system, leachate was pumped from the storage tanks and trucked to Hunt's Point Treatment Plant for treatment and disposal on a daily basis. In the summer of 1998, the need to truck the leachate was eliminated with the construction of an underground off-site force main, which transports the leachate from the landfill to the Burr Avenue Junction in the New York City combined sewer. The leachate is now directly discharged to the sewer system and treated at Hunt's Point sewer treatment plant (POTW).

The construction of a permanent cap and leachate collection system began in the Fall of 1994. Regrading of the surface was required due to the steep slopes, deep gullies and dense vegetation in parts of the site. The slope of the landfill was decreased to ensure that a high density polyethylene (HDPE) cover remains stationary.

The HDPE cover was placed over the entire landfill during 1996, and covered with soil. During the fall of 1996, problems with the soil being used to cover the HDPE liner were found. The soil was not able to support a grass cover. Work completed in 1998 added new soil so that a grass cover is growing over the landfill.

In 1989, the ATSDR accepted a request from U.S. Congressman Elliott Engel and U.S. Congressman Ron Wyden to perform a petitioned public health assessment of the Pelham Bay Landfill. The request was submitted by the Congressmen in response to community concerns on the potential link between childhood cancers and site-related contaminants. This public health assessment (PHA), is in response to the Congressmens' petition.

B. Site Visit

The following is a summary of some of the site visits done by either NYS DOH, NYC DOH or ATSDR. On March 18, 1986, Mr. William Gilday and Mr. Dennis Weiss from the NYS DOH, and Mr. Morris Hopkins from the NYC DOH performed a site inspection. The following observations were made: (1) strong odors on-site, (2) exposed piles of solid waste (3) open drainage ditches on-site or emerging from the site, (4) leachate seeps and areas saturated with liquids, (5) stressed vegetation, (6) odors more noxious at the top of landfill compared to the perimeter, (7) leachate seepage Exiting ATSDR Website and run-off overflow to well-used sidewalks and other portions of the park trail, (8) fishermen use the site to access the bay, (9) obvious foot paths on and adjacent to the site, (10) the landfill had no liner and soil-cover was incomplete, and (11) the site was used for fishing, jogging, horseback riding and bird watching.

On September 8, 1989, ATSDR Region II representative Ms. Denise Johnson and ATSDR Health Reviewer Dr. Sharon Williams-Fleetwood visited the landfill. The following observations were noted during the site visit: (1) dense vegetation had filled the fissures in the landfill's soil cover; (2) strong odors were detected near a drainage ditch on the north side of the site; (3) a surface seep was visible on the west side of the landfill; (4) the site fence was in need of repair; (5) persons were seen fishing along Pelham Bay Park's bay shore.

Representatives of the NYS DOH have been on-site several times in the 1990's. During visits prior to 1992, fishermen had been observed on-site, evidence of frequent use such as well worn foot paths and two small active fissures were observed on the top of the landfill. Since 1992, no unauthorized persons were observed on-site. On September 8, 1995, Dr. Lloyd Wilson and Ms. Katarina B. Holbrook of the NYS DOH visited the site to see the remediation activities at the site. The following observations were made: (1) 40 percent of the geo-membrane cap had been completed; (2) the leachate collection systems was in place and operating efficiently with no compromises to the system; (3) installation of a surface run-off system was in place and operating efficiently via anchor trenches which transport surface water into various ponds along the perimeter of the site; (4) the HDPE liner for the cap was being appropriately tested for leaks; (5) odors which are typical of municipal landfills were observed; and (6) air monitoring was on-going for the protection of the workers and adjacent communities. In the Fall of 1998, Dr. Wilson participated in the community tour and public meeting sponsored by the DEP to recognize the completion of construction for remediation of the site.

C. Demographics, Land Use, and Natural Resource Use

Demographics

From the 1990 Census, NYS DOH estimated that 26,954 people live within one mile of the PBL. Within one mile of the site, the population is of 72.9 percent white race, 21.8 percent black race, and 5.3 percent other races. By age, 5.3 percent of the population is under 6 years, 12.6 percent is 6-19 years, 57.7 percent is 20-64 years and 24.4 percent is 65 years or older. The PBL is within the boundary of zip code 10465, in which the median household income for 1989 was $37,116 and in which 6.6 percent of families live below the poverty level.

Land Use

Land in the immediate vicinity of the landfill is predominately used for residential and transportation purposes. Housing types vary in the areas surrounding the landfill. Residential neighborhoods are to the south and west of the landfill. The nearest residential area to the east is City Island. The nearest residence is Co-Op City, a high rise apartment complex one-half mile northwest of the site. Co-Op City consists of 35 high-rise towers ranging from 24 to 33 stories and 236 townhouses with two apartments each.

The land use for the area in Figure 2 (Appendix A) was characterized during the RI/FS. Residential land use accounts for 86 percent of the total number of lots (13,622). One and two family residences comprise almost 75 percent of the total number of lots in contrast to industrial uses which account for 0.3 percent, commercial activities 4.3 percent and vacant land 7.2 percent. Figure 2 (Appendix A) shows the 1993 zoning of the study area. Zoning descriptions are as follows; R2 district is limited to single family homes with a maximum dwelling density of 11 units/ acre, R3-1 district consists of small single and two family homes with maximum density of 42 units/acre, R3-2 district is the lowest density zone for multiple dwellings and consists of garden apartments or townhouses, R3A district allows for modest single and two family detached homes on narrow lots, R4 district is the same as R3-2 but with higher density, buildings are no taller than three stories, R6 district housing is between three and twelve stories with an allowable density of 176 units/acre which is Co-Op City. The commercial district (C3) is designed to permit waterfront recreation and boating and fishing uses. Typical development includes marinas, boat repair shops, and public or private beaches.

There is a variety of community facilities located in the study area, some are shown in Figure 2 (Appendix A). The schools and nursing homes represent the most sensitive portion of community facilities within the study area. There are about 524 students enrolled in Public School 160, and about 514 students enrolled in Villa Maria Academy (K-8). Pelham Bay Park lies southwest, west, and north west of the site. Pelham Bay Park is the largest public park within New York City and is about 2,118 acres. The area situated within the study area is called the Rice Stadium Area. The Rice Stadium Area consists of the following major community facilities: Rice Stadium and football field, horse riding stable, wildlife refuge, Memorial Grove and War Memorial, tennis courts, baseball fields, and playgrounds.

Natural Resource Use:

Eastchester Bay is used for swimming, boating, and fishing by local citizens. Prior to increased security in 1991, the landfill was used as access to Eastchester Bay.

The northwest corner of the PBL was previously used as a community garden (Appendix A, Figure 3). The garden was closed in 1988.

Public drinking water and industrial water supplies are provided by the New York City municipal reservoir system. This an extensive system which collects water from reservoirs in upstate New York. There are no private wells used for potable water within a mile of the site.

There was a municipal water supply main that ran along the north/north-west perimeter of the landfill. To reduce the potential for future human exposure, address community concerns, and protect public health, the New York City Department of Environmental Protection (NYC DEP) agreed to relocate the 20 inch water main even though there was no past exposure due to the water main location. The water main was relocated so that it now runs parallel to the Shore Road near the current landfill fence. Relocation prevents the remote possibility of contamination of municipal water supplies with site-related chemicals should the water supply distribution system undergo breaks or leaks.

Commercial shell fishing has not been permitted by the NYS DEC since 1994 in Eastchester Bay. Prior to 1994, permits were issued that required transfer of the shellfish to clean waters for a minimum period of 21 days before sale. This was necessary to remove biological contamination from the shellfish. Recreational shellfishing is not permitted. No information on the commercial harvest of finfish from Eastchester Bay is available. Recreational fisherman use Eastchester Bay regularly and reportedly consume their harvest.

D. Health Outcome Data

The NYS DOH maintains several health outcome data bases that can be used to generate site specific data if warranted. These data bases include a cancer registry, congenital malformations registry, heavy metal registry, occupational lung disease registry, reports of blood lead concentrations, vital records (birth and death certificates) and hospital discharge information. In response to citizen concerns the NYC DOH has evaluated cancer incidence data for the area near the PBL (NYC DOH 1993, NYC DOH 1994). The results of these studies are presented in the Health Outcome Data Evaluation section of this report.


COMMUNITY HEALTH CONCERNS

There are a variety of community health concerns associated with past exposures and site conditions associated with PBL. In the mid-1980's there were reports of noxious odors from seeps and open fissures in the landfill. Community residents complained of leachate seeps and surface run off that covered foot paths and roadways. Prior to interim remedial activities, trespassers accessed the landfill through holes in the fence around the perimeter of the landfill. The trespassers included children and adults.

Community health concerns that were identified by area residents, the Pelham Bay Task Force and the Science Advisory Committee are: (1) inhaling polluted air from the landfill, (2) eating finfish and hardshell fish from Eastchester Bay, (3) swimming and other recreational uses of Eastchester Bay, (4) inhaling, ingesting and dermally contacting contaminated leachate/groundwater and soil, (5) soil/gas migration of contaminants into the basements of nearby homes, (6) contaminating potable water from leaks or breaks in the municipal water mains, (7) flooding of nearby basements with contaminated water which originated from the landfill, and (8) release of landfill gases and dust during remediation and construction of PBL.

Another significant issue is that the community is concerned that past exposures to site-related contaminants are linked to cancer cases detected in adjacent communities. In March 1988, an elected official and several community residents from Pelham Bay area reported to the Environmental Epidemiology Unit of the NYC DOH a concern about a cancer cluster among residents of the communities adjacent to the PBL. Residents from these communities were concerned that cases of leukemia and other cancers and diseases detected within surrounding neighborhoods were excessive and may be related to exposure to toxic substances that originated from the landfill.


ENVIRONMENTAL CONTAMINATION AND OTHER HAZARDS

To evaluate if a site poses an existing or potential hazard to the exposed or potentially exposed populations(s), the site conditions are characterized. Site characterization involves a review of sampling data for environmental media (i.e., soil, surface water, groundwater, air) both on- and off-site and an evaluation of the physical hazards near the site which may pose an additional health risk to the community or receptor population(s).

Contaminants selected for further evaluation are identified based upon consideration of the following factors:

  1. Concentrations of contaminant(s) in environmental media both on- and off-site;

  2. Field data quality, laboratory data quality, and sampling design;

  3. Comparison of on-site and off-site contaminant concentrations in environmental media with typical background levels;

  4. Comparison of contaminant concentrations in environmental media both on- and off-site with public assessment comparison values for noncarcinogenic endpoints and carcinogenic endpoints. These comparison values include Environmental Media Evaluation Guides (EMEG's), Cancer Risk Evaluation Guides (CREGs), drinking water standards and other relevant guidelines; and

  5. Community health concerns.

The selected contaminants(s) are evaluated in the Public Health Implications section (Toxicological Evaluation) of this PHA to determine whether exposure to these chemicals is of public health significance.

Contaminants discussed in the On-site Contamination and Off-site Contamination subsections do not necessarily cause adverse health effects from exposures at the levels detected. The on-site and off-site contamination subsections describe what was found during investigations of the site. If a chemical is selected for further evaluation in one medium (e.g., soil, sediment, surface water, groundwater, air), that contaminant will also be reported in all other media, if detected.

Numerous environmental sampling events have been conducted since the landfill closed in 1979. For the purpose of evaluating sampling data and site conditions in this PHA, data reviewed by the NYS DOH and the ATSDR includes all available historical data, 1993 RI data, and data generated during the 1990 quarterly sampling rounds as part of initial remedial activities at the site.

A. On-site Contamination

Air Quality

The overall objectives of the 1993 RI air monitoring program were to identify maximum emission rates of landfill gases and measure ambient air contaminants attributable to the landfill at selected locations. Ambient air samples were collected on-site and off-site. During the RI, most of the samples were collected off-site in the community. On-site ambient air monitoring was specific to particulate sampling and was used to evaluate dispersive conditions associated with erosion and resuspension of surface soil materials and contaminants by winds. On-site particulate measurements were obtained at hot spot locations which were identified from the soil gas monitoring program. On-site soil gas monitoring data identified the rate at which various compounds were released from subsurface waste materials to the atmosphere. Municipal landfill gases are typically comprised mostly of methane. Emission rates [mass/area-time; micrograms per square meter (mcg/m2-sec)] of the soil gas were monitored using Emission Isolation Flux Chambers (EIFCs).

In 1990, WCCI measured soil gas emissions on a quarterly basis using EIFCs at six locations on the landfill. The on-site emission rate data indicate that most analytes were detected at least once and with considerable variation in emission rates between locations. The compounds detected and the range of emission rates are as follows: benzene (not detected (ND)-1.7480 mcg/m2-sec), cumene (ND-1.0278 mcg/m2-sec), chlorobenzene (ND-4.3172 mcg/m2-sec), ethylbenzene (ND-1.4365 mcg/m2-sec), heptane (ND-0.1671 mcg/m2-sec), hydrogen sulfide (ND-0.5669 mcg/m2-sec), tetrachloroethene (ND-0.8744 mcg/m2-sec), toluene (ND-0.1752 mcg/m2-sec), xylenes (ND-1.0377 mcg/m2-sec). (Note: ND indicates that the compound was not detected in at least one sample.) All of these contaminants were below applicable public health assessment comparison values.

Fifty volatile organic compounds (VOCs) and semi-volatile organic compounds (SVOCs) as well as ammonia, hydrogen sulfide and hydrogen cyanide were analyzed during the 1992 soil gas sampling. Ammonia and hydrogen sulfide were detected only once at a concentration above the minimal level of detection. Hydrogen cyanide was not detected at any of the sample locations. Of the 50 VOCs/SVOCs, 28 compounds were detected and the majority of these compounds are standard solvents and refrigerants. Methane was the predominant gas detected, which is typical of landfills of the PBL age. Methane was detected in five of the eight wells at a range of 965 - 9093 mcg/m2-sec. Of the remaining compounds, those exhibiting the highest emission rates and the range of concentrations detected are: acetone (ND-0.136 mcg/m2-sec); benzene (ND-0.201 mcg/m2-sec); cumene(ND-0.098 mcg/m2-sec); chlorobenzene (ND-1.131 mcg/m2-sec); ethylbenzene (ND-0.307 mcg/m2-sec); toluene (ND-0.0809 mcg/m2-sec) and xylenes (ND-0.0665 mcg/m2-sec). Based on the emission rates, corresponding air concentrations were calculated using computer models. The modeled air concentrations for all 28 contaminants were below applicable public health assessment comparison values and are not discussed further in this document.

In addition, soil gas was sampled at the perimeter of the site by WCCI during the 1989-1991 site investigation and the 1993 RI. Results of these analyses are similar. During the 1993 RI, seven soil gas samples were analyzed; two locations were off-site to provide background values. The purpose of the soil gas survey was to measure the levels of methane leaving the site perimeter by horizontal transport through the soil. Three perimeter locations had soil-gas methane levels that exceeded background levels. These three sample stations are located at the northeast area of the site. This same area showed relatively high levels of methane during the 1989 - 1991 site investigation. The off-site locations or reference locations in Pelham Bay Park detected only background levels of methane.

Results of the RI particulate and particulate bound concentrations program found only trace amounts of metals (inorganics) at both on-site and off-site locations. Particulate concentrations downwind of the landfill were not elevated compared to upwind concentrations suggesting that the source of particulate and metals are regional, and are not related to the landfill. No polycyclic aromatic hydrocarbons (PAHs) were detected in any of the samples.

During construction of the landfill cover, which is high density polyethylene (HDPE), from December 1994 to November 1995, an intensive real-time air monitoring program was implemented to determine if the construction activities resulted in releases of contaminants. Monitoring was done from December 1994 to November 1995 at locations upwind and downwind of the immediate work area, and downwind at the site perimeter. Monitoring was also done periodically at one of three designated off-site locations. The monitoring included measurements of dust, total volatile organic chemicals (VOC), hydrogen sulfide, and four specific volatile chemicals. These measurements were made anytime construction of the HDPE cover was on-going as part of the health and safety plan. If an action level was exceeded, work such as watering to reduce dust was required to reduce the air contamination. The Health and Safety plan was protective of the workers and public.

Groundwater/Leachate

According to the 1993 RI there is no separate classification for leachate and groundwater at this site. Leachate typically is defined as the liquid wastes from a landfill which often includes groundwater and rainwater. Because groundwater at the site is in contact with the waste in the landfill, it is not distinguished from leachate. Therefore, the 1993 RI data combined both media into one as groundwater/leachate. To be consistent with the 1993 RI, groundwater and leachate are not separated in this document. The monitoring well and seep samples collected during the 1993 RI adequately characterized the nature and extent of contamination of the groundwater/leachate within the PBL. A summary of the important findings from the RI and previous sampling events are presented below.

Precipitation that infiltrates the surface of the landfill moves through the waste, leaching contaminants into the groundwater system. Contaminant transport in the groundwater pathway includes: (1) shallow groundwater flow in the fill (waste or garbage) and till (sand and silt) units; (2) discharges as seeps; and (3) groundwater flow in bedrock. Based on results presented by the 1993 RI, groundwater flow through joints and fractures in the bedrock beneath the landfill is insignificant (Woodward Clyde Consultants, Inc. 1993). The findings indicate that the joints and fractures are tight and not well interconnected, resulting in slow migration of fluids through bedrock. Additionally, the leachate collection system which was completed in 1992, collects about 75,000 gallons/day of the groundwater/leachate. About 10 percent of the groundwater/leachate, 7,500 gallons/day, are estimated to reach Eastchester Bay.

In 1980, the NYC DOS contracted with Parson-Brinkerhoff-Cosulich to conduct an environmental investigation of five New York City landfills including the PBL. They, in turn, subcontracted Geraghty and Miller Consultants to do the field work for the investigation. Arsenic, barium, cadmium, chloride, chromium, lead, manganese, mercury and selenium were all found at concentrations above the New York State DEC groundwater standards (Woodward-Clyde Consultants, 1983). In 1982 Parsons-Brinkerhoff-Cosulich did another investigation. In six groundwater samples they found no arsenic, no chromium and no PCBs. The range of concentrations for the contaminants found are: cadmium [ND-37 micrograms per liter (mcg/L)]; copper (ND-180 mcg/L); lead (ND-490 mcg/L); mercury (ND-7.5 mcg/L); silver (ND-20 mcg/L); zinc (50-790 mcg/L); total phenols (ND-72 mcg/L); cyanide (ND-160 mcg/L); toluene (ND-410 mcg/L) and chlorobenzene (ND-370 mcg/L).

In 1988, NYC DOS sampled and analyzed leachate seeps emanating from the landfill and determined that leachate quality met NYS groundwater standards (NYC DOH 1988) with the exception of lead, 1,4-dichlorobenzene, and naphthalene. These data and the exact location of the sampling were not available to review. In March of that same year, the NYS DOH and NYS DEC collected leachate samples from the side of the landfill adjacent to Shore Road and Pelham Bay Park, and concluded that (1) leachate was comprised of compounds which are common for leachate from municipal solid waste landfills, (2) the detected levels were low when compared to other landfills, and (3) the concentrations of most pollutants in the leachate were below New York State groundwater quality standards (Woodward Clyde, 1993).

In November 1989, twelve monitoring wells were installed at the landfill by WCCI upon request by the NYC DOS. These wells were sampled quarterly in 1990. Most of the contaminants analyzed for were either not found or found at low part per billion concentrations. The five samples from Monitoring Well 102, which is located on-site of the south side of the landfill, consistently contained the highest concentrations of the contaminants found. The samples from this well contained benzene (8 mcg/L to 56 mcg/L), ethylbenzene (14 mcg/L to 73 mcg/L), toluene (39 mcg/L to 220 mcg/L), xylenes (ND to 160 mcg/L), 2-butanone (ND to 5,000 mcg/L), 4-methyl-2-pentanone (30 to 230 mcg/L), 2-hexanone (ND to 53 mcg/L), naphthalene (ND to 45 mcg/L), phenanthrene (ND to 15 mcg/L), pyrene (ND to 12 mcg/L), fluoranthene (ND to 5 mcg/L), 2-methylphenol (66 mcg/L to 150 mcg/L), 2,4-dimethylphenol (ND to 260 mcg/L), 4-methylphenol (ND to 220 mcg/L), phenol (ND-130 mcg/) and bis(2-ethylhexyl)phthalate (83 to 240 mcg/L). Other than the finding of 77 mcg/L of naphthalene in one of the four samples collected from monitoring well 105 (MW-105) the maximum concentration detected are those reported for MW-102.

Pesticides were detected in seven of the 12 monitoring wells sampled quarterly in 1990. Of the seven wells, only one (MW-102) was found to contain pesticides during each sampling event. This well is located in the interior of the landfill. Total pesticide concentrations in samples from MW-102 ranged from 0.78 to 1.478 mcg/L. Total pesticide concentrations in the other five wells were less than 0.4 mcg/L. Wells containing pesticides are located within the landfill (MW-102) and along the southern (MW-106 and MW-110), eastern (MW-104 and MW-105), and northern (MW-112) edges of the site. No pesticides were detected in monitoring wells on the northwest and southwest sides of the site or in one of the wells (MW-103) in the northern end of the landfill.

Several metals were detected in groundwater samples at levels which exceeded NYS DEC groundwater quality standards. Three of these metals exceeded standards repeatedly in nearly all the wells: Iron (943 - 43,400 mcg/L); magnesium (3,480 to 879,000 mcg/L); and sodium (8,590,000 - 31,790,000 mcg/L).

Leachate was sampled quarterly during 1990 and once in 1991 in three locations. The total of VOCs and SVOCs ranged from ND-91 mcg/L. The highest concentrations were for chlorobenzene and bis(2-ethylhexyl)phthalate. Further details on these data could not be located. Four metals were also detected repeatedly in concentrations above NYS DEC Groundwater Quality Standards as follows: chromium (43.4-226 mcg/L), magnesium (41,800-184,000 mcg/L), sodium (542,000-4,237,000 mcg/L), and arsenic (61.5-97 mcg/L).

During the 1993 RI, 38 samples of groundwater were analyzed for inorganic contaminants. The range of concentrations observed from the monitoring well samples are as follows: arsenic (ND-63.4 mcg/L), barium (164-3,090 mcg/L), cadmium (ND-29.1 mcg/L), calcium (ND-2,752,000 mcg/L), chromium (ND-1,240 mcg/L), cobalt (ND-77.3 mcg/L), copper (ND-1,130 mcg/L), cyanide (ND-267 mcg/L), iron (165-194,000 mcg/L), lead (ND-423 mcg/L), magnesium (5,290-1,936,000 mcg/L), manganese (77.8-29,600 mcg/L), mercury (ND-1.1 mcg/L), nickel (ND-483 mcg/L), potassium (2,950-1,431,000 mcg/L), sodium (10,700-8,000,000 mcg/L), vanadium (5.2-2,860 mcg/L), and zinc (20.2-7,110 mcg/L).

During the 1993 RI, 40 monitoring well (MW) samples were analyzed for VOCs. Methylene chloride, a common laboratory contaminant, was detected in many of the monitoring well samples, including quality control blanks and these results were rejected during validation of the data. The most prevalent contaminant detected was 2-propanone (acetone) which was detected in 12 monitoring well samples ranging from ND-2,100 mcg/L; only trace amounts were detected in any seep locations. Chloroform was found in three samples at concentrations ranging from 2 mcg/L to 20 mcg/L. 1,2-Dichloroethene was detected in two samples each at 1.0 mcg/L. One sample contained tetrachloroethene at 6.0 mcg/L and trichloroethene at 5.0 mcg/L. The following VOCs were detected in less than 25 percent of the groundwater/leachate samples; benzene (ND-62 mcg/L), chlorobenzene (ND-46 mcg/L), ethylbenzene (ND-36 mcg/L), toluene (ND-230 mcg/L), and xylenes (ND-200 mcg/L).

Thirty-five monitoring wells were analyzed for SVOCs. The polycyclic aromatic hydrocarbons (PAHs) were the most frequently detected compounds within groundwater/leachate. The PAHs were limited to nine samples collected from monitoring wells within the fill. Of the PAHs, naphthalene was detected in the highest concentration and ranged from ND-140 mcg/L. Other PAHs detected include 2-methylnaphthalene, acenaphthylene, acenaphthene, anthracene, chrysene, benz(a)anthracene, dibenzofuran, fluoranthene, fluorene, and pyrene. The total amount of PAHs detected per sample ranged from ND to 282 mcg/L.

Phenolic compounds were detected in 5 of the 40 monitoring wells. The highest concentration was 290 mcg/L for 2,4-dimethyl phenol. 2-methyl phenol and 4-methyl phenol were detected at a range from 4-51 mcg/L. The most frequently detected phthalate is bis(2-ethylhexyl)-phthalate with a range of 2-38 mcg/L. Phthalates were found in 13 of the 40 samples.

Pesticides were detected in 27 monitoring well samples. Most monitoring well pesticide detections were denoted with a "J", indicating that the concentration is estimated. The samples were analyzed for twelve different pesticides. Methoxychlor, which was the pesticide found at the highest concentration, was found in one sample out of 36 at a concentration of 0.41 mcg/L. The pesticide found in the next highest concentration is dieldrin at 0.091 mcg/L. Dieldrin was found in six of the 36 samples and is the pesticide found most often. In general, the pesticides were found infrequently and at low concentrations. The PCBs, Aroclor 1016 and Aroclor 1260 were found in one of 36 samples with a range between 0.84-1.0 mcg/L.

Seeps

During the 1993 RI, eight seep samples were collected. Acetone was found in one sample at 12 mcg/L and 2-butanone was detected in another sample at 170 mcg/L. Benzene was found at a concentration from 2.0 - 4.0 mcg/L. Chlorobenzene was found from ND-120 mcg/L. Ethylbenzene was found in three samples with the highest concentration being 15 mcg/L. Toluene was found in two samples at 7 mcg/L and 81 mcg/L. Xylenes were found in three samples with the highest concentration being 65 mcg/L.

Six different PAHs were detected in four of the eight seep samples. Naphthalene was the PAH found at the highest concentration (33 mcg/L). The other PAHs detected include 2-methylnaphthalene, acenaphthene, anthracene, fluorene and pyrene. Two samples contained 2,4-dimethylphenol, 4-methylphenol and 4-nitrophenol. 2,4-Dimethylphenol was found at a high concentration of 51 mcg/L; all other results were below the detection limit. Three phthalates were also found: bis(2-ethylhexyl)phthalate, di-n-butylphthalate and di-n-octylphthalate.

Only one pesticide, delta-BHC, could be verified as being present in the seeps. Delta-BHC was found in one of the eight seep samples at a concentration of 0.0099 mcg/L. Aroclor 1016 was the only PCB mixture found; it was found in one sample at a concentration of 0.88 mcg/L.

Like the groundwater samples, many inorganic chemicals were found in the seep samples. Arsenic was detected in seven of the eight seep samples from 1.6 mcg/L to 89.1 mcg/L. Barium was found in all of the seep samples from 104 mcg/L to 8,470 mcg/L. Boron was detected in all of the seep samples ranging in concentration of 1,570 mcg/L to 8,900 mcg/L. Chromium also was detected in eight of the seep samples ranging in concentration from 26 mcg/L to 483 mcg/L. Lead was detected in each of the seep samples ranging in concentration from 3 mcg/L to 2,780 mcg/L. Mercury was detected in four of the eight samples at a concentration less than 5 mcg/L. Vanadium was detected in all of the eight seep samples ranging in concentration from 4.9 mcg/L to 822 mcg/L. Zinc was detected in all of the seep samples ranging in concentration from 28.1 mcg/L to 1,330 mcg/L. None of the organic or inorganic contaminants in these leachate seeps exceeded public health comparison values.

Aluminum, antimony, beryllium, calcium, cobalt, copper, iron, magnesium, manganese, nickel, potassium, sodium, and cyanide have all been found in leachate at concentrations and frequencies similar to those in the groundwater samples. This is one reason why the groundwater and leachate at this landfill are not considered to be separate.

Soils

In November 1989, WCCI, under contract with the NYC DOS collected eight soil samples, which were analyzed for VOCs, PAHs, pesticides/PCBs and inorganic compounds (Woodward Clyde Consultants, 1990). The VOCs detected were: 2-butanone, detected in one sample at 0.210 milligrams per kilogram (mg/kg), acetone detected in three samples at 0.120 mg/kg, 0.220 mg/kg, and 0.900 mg/kg, respectively, chlorobenzene detected in one sample at 0.004 mg/kg and carbon disulfide detected in one sample at 0.007 mg/kg. One sample contained the following PAHs: 2-methylnaphthalene(0.060mg/kg); acenaphthalene(0.075mg/kg); anthracene(0.076 mg/kg); benzo(a)anthracene(0.200mg/kg; benzo (a)pyrene(0.130mg/kg); benzo(b)fluoranthene(0.110mg/kg); benzo(g,h,i)perylene (0.130 mg/kg; chrysene (0.220 mg/kg); fluoranthene (0.650 mg/kg); fluorene (0.140 mg/kg); indeno(1,2,3-cd)pyrene (0.120 mg/kg); naphthalene (0.078 mg/kg);phenanthrene (0.810 mg/kg) and pyrene (0.560 mg/kg). One other sample contained one PAH. Fluoranthene was detected in this sample at 0.037 mg/kg. The other semi-volatile compounds detected were bis(2-ethylhexyl)phthalate and di-n-butylphthalate. Bis(2-ethylhexyl)phthalate was found in five samples at concentrations ranging between 0.041 and 0.300 mg/kg. Di-n-butylphthalate was found in one sample at 0.078 mg/kg. None of these soil contaminants exceeded either typical background levels and/or public health assessment comparison values. No pesticides or PCBs were detected in any of the soil samples.

During the 1993 RI conducted by WCCI, on-site soil samples were collected from soil borings, surface soil and the former community garden. A total of 24 soil boring samples were analyzed for organic and inorganic compounds. The soil boring depth ranged from 0.5 to 12 ft. and the surface soil was sampled at 0-2 inches. Monitoring well MW-124 (soil samples SB-124S1; 0-1 inch depth and SB-124S2; 8-10 inch depth) is the reference location used to obtain background data for all on-site and off-site soil samples. The reference monitoring well is in Pelham Bay Park about 300 feet south of the edge of the landfill in an area which cannot be contaminated by on-site groundwater since it is in a hydraulically upgradient direction from the landfill.

The results from the 1989 and 1992 soil sampling show that inorganic contaminants were at similar levels during both sampling events. The 1993 data for those contaminants that were found in at least 20 percent of the samples collected are in Table 1A (Appendix B). None of these inorganic contaminants detected in either round of sampling exceeded typical background levels and/or public health assessment comparison values.

In general, data from the 1993 RI show about the same levels of inorganic contaminants in shallow, subsurface, garden and reference soils. The shallow soils are from samples collected at a depth of less than 2.0 feet. Samples taken from subsurface soils include samples from the fill. Four of the garden samples were collected from 0 to 2 inches in depth. One garden sample was collected from one to two feet. The two reference samples were collected from a boring installed in Pelham Bay Park in an area which did not receive waste from the landfill.

Acetone was the only volatile organic compound found in more than 20 percent of the 1993 RI samples. Most of these concentrations were less than 0.020 mg/kg. The semi-volatile organic compounds found were either PAHs or phthalates (see Table 1B, Appendix B). The PAH, benzo(a)pyrene, and the PCB mixture, Aroclor 1254, exceeded typical background levels and/or public health assessment comparison values (Table 2A, Appendix B).

In 1988, analysis of a soil sample collected from the former community garden contained lead at 314 mg/kg. During the 1993 RI, five soil samples were collected from the area of the former community garden. Four were surface samples and one sample was collected at 1-2 ft. depth. The only VOCs detected were chloroform and toluene at 0.001 mg/kg. Three pesticides were detected which ranged from ND-0.440 mg/kg. Aroclor 1254 was detected in all samples at levels which ranged from 0.053-1.100 mg/kg. Contaminants in the 1993 soil samples that exceed public health assessment comparison values are the PCB mixture, Aroclor 1254, and the PAHs, benz(a)anthracene and benzo(a)pyrene (Table 2B, Appendix B).

B. Off-Site Contamination

Air

Off-site air monitoring was performed on a quarterly basis in 1990 by WCCI at the request of NYC DOS. Off-site measurements were collected at locations that best represented upwind conditions. A total of 11 VOCs and SVOCs were detected upwind at least once during the sampling event. One of the upwind samples showed the following: benzene (1,713 mcg/m3), cumene (142 mcg/m3), chlorobenzene (177 mcg/m3), ethylbenzene (1,807 mcg/m3), tetrachloroethene (354 mcg/m3), toluene (71 mcg/m3), and xylenes (142 mcg/m3). These contaminants were either not detected or detected at very low levels in the other off-site samples. Subsequent measurements made off-site, including during the 1993 RI, have shown these contaminants at concentrations not anywhere near these levels. Because they represent an upwind location, they do not reflect an impact from the PBL.

Off-site air sampling measurements were taken during the 1993 RI at eight off-site locations (Figure 4). Five of the eight locations chosen included sensitive sub-populations. These locations are: the Pelham Bay Park (pedestrian walkway), adjacent to Cop's Beach, the residential location on Bayshore Avenue, the recreational area within Co-Op City and the New York City Police Department Unit Troop D. The remaining three locations were selected to further evaluate concentrations in areas typically downwind from the landfill.

All of the 1993 RI off-site samples were 24 hour samples collected over a 10-day sampling period in July 1992. The majority of the maximum contaminant concentrations were recorded on July 14, 1992. Most of the contaminants were found at levels typical of urban air.

Compounds associated with vehicle emissions that were consistently found included benzene, toluene, ethylbenzene and xylenes. The maximum concentrations found for these compounds are 9.75 mcg/m3, 241 mcg/m3, 7.5 mcg/m3 and 40.6 mcg/m3, respectively. Most of the toluene and xylene detected was below 20 mcg/m3, and most of this was believed to be from laboratory contamination. With the exception of benzene, no air contaminants exceeded background levels and/or public health assessment comparison values for contaminants in ambient air. Benzene, which is typically associated with vehicle emissions, slightly exceeded the typical background level of 6 mcg/m3 (ATSDR 1997). Tetrachloroethene was found in one sample at a concentration of 406 mcg/m3. The source of the tetrachloroethene in this sample is unknown, but almost all of the other values for tetrachloroethene were below 5 mcg/m3. Methane was found at a maximum concentration of 21,351 mcg/m3. Methane was the only compound for which off-site measurements showed elevated concentrations.

The maximum mass of particulate found was 63 micrograms per cubic meter on July 14. This level is below the 24 hour standard of 150/mcg/m3. Most of the results showed particulate levels between 9 mcg/m3 and 30 mcg/m3. Review of the frequency of detection of the target compounds by date and location indicates that compounds were detected across the entire monitoring network regardless of wind direction. This suggests that there are air emission sources other than PBL, since downwind locations from the landfill would have had the highest concentrations of these contaminants if they were coming from the landfill.

Air modeling techniques were used during the 1993 RI to evaluate potential effects of gaseous landfill emissions on surrounding communities. An air model analysis was performed by WCCI using the Industrial Source Complex model Version 2 (ISC2). The basis of the modeling application is to convert on-site emission rates (mcg/m2-sec) through mathematical processes to estimate ambient air concentrations (mcg/m3) at receptor populations located off-site. Modeling analyses of short-term emissions were performed using the on-site emission rates measured by the EIFC. Results from the short-term analysis indicate that landfill emissions can account for no more than 25 percent of the VOCs detected downwind in the community, but could account for the majority of methane measured in the community.

Surface Water

The NYC DOH sampled bathing waters within Eastchester Bay in the vicinity of the landfill during the last week of April, 1988. The water samples were collected directly off-shore in the following locations: Orchard Beach, City Island, Watt Ave., Country Club Road, and Edgewater Park. Samples were collected one foot from the landfill, and from undiluted leachate. In addition, sampling was conducted at high, mid, and low tide. Analyses were performed for volatile organic compounds, pesticides/herbicides, PCB's, PAH's, phenols and inorganic compounds. Except for one leachate sample, all of the compounds analyzed for were not detected. Results of the analyses showed that inorganic compounds (metals) were at levels below the drinking water standards for all samples with the exception of chromium, which was detected at 100 ppb in one leachate sample. Microbiological results were within the standards for bathing beaches. The NYC DOH concluded that the waters are suitable for swimming and do not pose a present or future public health threat during recreational use of Eastchester Bay. The NYS DOH participated in the assessment of the surface waters and reached the same conclusions (NYS DOH 1988).

Surface water samples were collected from five locations in Eastchester Bay for chemical analysis in January and July 1990 by WCCI under the direction of the NYC DOS. Acetone was the only organic compound detected in the samples and was attributable to laboratory cross-contamination. Six inorganic compounds were detected: barium, calcium, magnesium, manganese, potassium, and sodium. The analysis showed barium (9-23 mcg/L), calcium (205,000-254,000 mcg/L); magnesium (720,000-969,000 mcg/L); manganese (10-88 mcg/L); potassium (228,000-297,000 mcg/L) and sodium (8,590,000-31,790,000 mcg/L).

During the 1993 RI, further surface water sampling and analysis was conducted by WCCI. Samples were collected and analyzed from a total of eight locations within Eastchester Bay. Samples SW-1 through SW-6 were near the landfill seawall and SW-7 and SW-8 along the beach southwest of the landfill. One reference location (SW-9) was located two miles south of the landfill. The samples were collected at high and low tides. A total of 18 surface water samples were analyzed for VOCs, SVOCs, pesticides, PCBs and inorganic compounds. Methylene chloride was the only VOC detected and was attributed to laboratory cross-contamination. Pyrene was the only PAH detected at 12 mcg/L. Two phthalates were detected at 2-4 mcg/L. No PCBs were detected in any of the samples. Five pesticides were detected as follows: 4,4'-DDD (0.023 mcg/L), alpha-chlordane (0.025 mcg/L), delta-BHC (0.0071 mcg/L), endosulfan sulfate (0.03-0.27 mcg/L) and endrin (0.15 mcg/L).

The following inorganic compounds were not detected in any of the surface water samples: antimony, barium, boron, cadmium, chromium, cyanide, selenium, silver, thallium, and zinc. Inorganic chemicals typical of salt water were detected at high concentrations: calcium (193,000-305,000 mcg/L), magnesium (808,000-1,070,000 mcg/L), potassium (231,000-314,000 mcg/L), and sodium (10,700-8,764,000 mcg/L). Nickel was detected in three of the 18 surface water samples in a range from 10.5-157 mcg/L. Lead was detected in 12 of the 18 samples. Most of these levels were similar to levels found in quality control blank samples and therefore indicate they were not actually in the water. However, some samples clearly contained lead. The levels ranged from 1.4-13.3 mcg/L. Mercury was found in four of the 18 samples collected, at a range of 0.2-9.5 mcg/L. The concentration of metals found in the samples near the landfill are similar to the values at the reference station.

No organic or inorganic contaminants detected in any of the surface water samples exceeded NYS DEC surface water standards and/or public health assessment comparison values.

Basement Water Sampling

As part of the 1993 RI, water from resident basement sumps and flooded basements was sampled. The sampling was performed by WCCI at the request of SAC committee members and under the authorization by the NYC DEP. Four residential basements were sampled on July 16, 1992 after an area rainfall event. Each of the samples were analyzed for VOCs, SVOCs, pesticides/PCBs, total metals, and cyanide. The results of the analyses found very low levels of pesticides in two homes (less than 1 mcg/L) and also below health comparison values. The inorganic analysis detected arsenic, barium, calcium, copper, iron, lead, magnesium, manganese, potassium, and sodium in two homes. In addition aluminum, vanadium and zinc were detected in one of those homes. The only metals detected in basement water samples that exceeded NYS DEC groundwater standards are iron, lead, sodium, and manganese, which were found in two homes. The range of concentrations found for each of these contaminants is as follows: iron (54-2,510 mcg/L); lead (3.4-66.9 mcg/L); sodium (27,500-33,100 mcg/L) and manganese (214-1,510 mcg/L).

Sediment

During the 1993 RI, sediment samples were taken from six locations near the seawall of the landfill (SD-1 through SD-6), two samples in the bay near the beach southwest of the landfill (SD-7 and SD-8), and two locations on the beach southwest of the landfill (SD-10 and SD-11). Samples were collected at 0-6" in depth (Figure 5, Appendix A). Sediment was also collected from a reference location (SD-9) two miles south of the landfill. SD-1 through SD-9 correspond to surface water sample locations (SW-1 through SW-9).

Three replicate sediment samples were collected at each of the eleven locations and analyzed for VOCs. Acetone was the only VOC detected, at concentrations ranging from 0.026-0.044 mg/kg. Six replicate sediment samples were collected and analyzed for SVOCs at each of the eleven locations. The results discussed are the mean values of the six replicates. The highest concentration of PAHs was found in SD-6 with a total concentration of 23.8 mg/kg. The PAH pyrene, had the highest concentration (5.08 mg/kg). The beach sediment locations (SD-10 and SD-11) contained total PAH concentrations of 1.06 and 1.28 mg/kg, respectively. The range of PAH concentrations detected in the eleven sediment samples are as follows: acenaphthene (ND-0.255 mg/kg); acenaphthylene (ND-0.352 mg/kg);anthracene (ND-0.633 mg/kg); benz(a)anthracene (0.099-2.03 mg/kg);benzo(a)pyrene (0.078-1.67 mg/kg); benzo(b)fluoranthene (0.091-2.48mg/kg);benzo(g,h,i)perylene (0.047-0.605 mg/kg); benzo(k)fluoranthene (0.090-2.23 mg/kg); chrysene (0.112-2.42 mg/kg); dibenzo(a,h)anthracene (ND-0.158 mg/kg); fluoranthene (0.190-2.60 mg/kg); fluorene (ND-0.282 mg/kg); indeno(1,2,3-c,d)pyrene (0.059-0.608 mg/kg); phenanthracene (0.111-2.18 mg/kg); and pyrene (0.137-5.08 mg/kg). Similarly, the highest concentration of phthalate was found in SD-6 and the lowest concentrations in SD-10 and SD-11. The range of bis(2-ethylhexyl)phthalate found is 0.038 mg/kg to 8.85 mg/kg.

Six pesticides were also detected in sediment samples. None were detected in SD-10 and SD-11. The range of values reported in the sediments were 4,4'-DDD at ND-0.180 mg/kg; 4,4'-DDE at ND-0.130 mg/kg; 4,4'-DDT at ND-0.070 mg/kg; dieldrin at ND-0.066 mg/kg; endosulfan sulfate at ND-0.117 mg/kg; and delta-BHC at ND-0.290 mg/kg.

The levels of inorganic contaminants are similar to the PAH and pesticide data in that the lowest concentrations were detected in SD-10 and SD-11. No organic or inorganic contaminants detected in any of the sediment samples exceeded typical background levels or public health assessment comparison values.

Sediment samples 10 and 11 contained the lowest concentration of contaminants because they also contained the lowest percentage of organic carbon. Contaminants are adsorbed onto the carbon and so sediment with higher carbon concentrations typically have higher levels of inorganics. Because the percentage of carbon is related to contaminant levels, to compare contaminant levels between samples the results are often equated based on carbon content through a process called normalization. Based on normalization analysis bulk sediment concentrations of metals, SVOCs and PAHs indicate that none of the sample locations in the vicinity of the landfill were considerably different from the reference location. The results of this analysis suggests that the landfill is not the primary source of the contaminants found in the sediments.

Off-Site Soils

Off-site surface soil samples were collected from borings and surface soil during the 1993 RI. Eighteen off-site surface soil samples were also collected as part of the 1993 supplemental RI (Woodward Clyde Consultants, 1993), to evaluate the potential for soil contamination from leachate, seeps and surface water runoff from the landfill.

The results of the off-site monitoring for the 1993 RI are summarized in Table 1B. No volatile organics were found in the 1993 RI off-site samples, except for one sample, which had a total concentration of 0.011 mg/kg. Semivolatile organics, including polycyclic aromatic hydrocarbons were found in most of the samples (Table 1B, Appendix B). Metals and other inorganics, were found in every sample (Table 1A, Appendix B). Contaminants in off-site soil that exceed public health comparison values are the PAHs; benzo(a)pyrene (7.6 mg/kg, highest level found) and dibenz(a,h)anthracene (2.0 mg/kg, highest level found). The supplemental RI, showed similar results to the RI, although the semi-volatiles, in general, were lower. Both studies showed that the landfill is not the source of the contaminants in the off-site soil. The basis for this conclusion is that the samples collected from areas potentially contaminated by the landfill were similar to background samples (i.e., samples collected from areas not contaminated by the landfill).

Fish/Shellfish

During the 1993 RI, WCCI collected and sampled 34 finfish and 50 shellfish during a two week period from Eastchester Bay. Samples were collected from two locations near the landfill and one location away from the landfill (Figure 6, Appendix A). The three locations sampled included the eastern and southern seawalls of the landfill, as well as the reference station in the middle of Eastchester Bay about one mile south of the landfill. The samples were analyzed for cadmium, lead, mercury, PCBs, pesticides, percent moisture and percent lipids. The finfish included 15 Atlantic Silverside (wholefish), two tautog (skinless tautog), two American eel (beheaded and eviscerated) and 13 flounder (skinless fillet). Shellfish included blue crab (muscle tissue), hardclam (soft tissue) and blue mussel (soft tissue). Fish caught nearer to the landfill did not show higher concentrations of contaminants.

The chemicals detected in more than 20 percent of the fish caught include lead, mercury and 4,4-DDE. A review of the data for those chemicals which were found in more than 20 percent of the fish is below.

The mean lead concentrations detected in flounder caught at the eastern seawall, southern seawall, and reference location are 0.04 mg/kg, 0.09 mg/kg and 0.5 mg/kg, respectively. The mean concentrations of mercury are 0.07, 0.04 and 0.08 mg/kg, respectively. Atlantic Silversides contained a range of 0.11 to 0.28 mg/kg of lead and 0.03 to 0.05 mg/kg of mercury. All 15 of the Atlantic Silversides contained 4,4-DDE. The concentration ranged from 0.027 mg/kg to 0.051 mg/kg. The reference station Atlantic Silverside had a concentration of 0.027 mg/kg, whereas the eastern and southern seawall Atlantic Silverside concentrations were 0.051 and 0.045 mg/kg, respectively.

Cadmium detected in bluecrab shellfish at each of the locations ranged from 0.02 mg/kg to 0.6 mg/kg. Five crabs were sampled from each of the three locations. The reference location mean cadmium concentration was 0.02 mg/kg. The mean lead concentration at both the sample and reference locations is 0.09 mg/kg. The mean mercury concentrations detected are 0.07 mg/kg and 0.20 mg/kg. The reference sample had a mercury level of 0.09 mg/kg.

Five clams were sampled at each of the three locations. The hardclams contained mean lead concentrations of 1.2 mg/kg from the eastern seawall and 1.3 mg/kg from the southern seawall. The lead concentration for the reference sample was 2.2 mg/kg. Similarly, cadmium was detected in hardclams from the eastern seawall at 0.35 mg/kg and from the southern seawall at 0.41 mg/kg. The mean for the reference location was 0.48 mg/kg.

Five blue mussels were collected from each of two different stations on the eastern seawall, one location on the southern seawall and the reference station. The mean concentration of cadmium ranged from 0.43 to 0.67 mg/kg for the three stations near the landfill. The reference station mean was 0.40 mg/kg. The lead concentration ranged from 1.8 to 4.1 mg/kg for the three stations near the landfill. The reference station mean was 1.4 mg/kg. The mean concentration ranged from 0.03 to 0.04 mg/kg for mercury at the three stations near the landfill. The reference station mean value is 0.04 mg/kg.

Indoor Air Quality

During the 1993 RI, residential indoor air quality was measured and analyzed. The air quality study was conducted by WCCI at the request of the SAC to identify the presence or absence of air contaminants. Contaminant selection was determined by the SAC. Air samples were collected from three residential homes within the nearby community and the results indicate low levels of VOCs. The NYC DEP along with guidance from the NYC DOH and the NYS DOH informed the homeowners of the indoor air sampling results. It was concluded that the types and low levels of VOCs detected were typical of findings from other studies of indoor residential air quality such as the US EPA Total Exposure Assessment Methodology studies conducted during the 1980s.

Drinking Water

In the fall of 1992, NYC DEP sampled potable water from 53 residences served by the NYC Water Supply in the Pelham Bay area, based on citizen's concerns. The analysis included testing for 23 metals. Twelve samples were also analyzed for VOCs, SVOCs, pesticides and PCBs. Lead and copper were the only analytes found in exceedance of the NYS DOH drinking water standards. These contaminants are not attributed to the landfill, but are believed to be attributed to lead and copper in domestic plumbing.

C. Quality Assurance and Quality Control

In preparing this public health assessment, ATSDR and the NYS DOH rely on the information in the referenced documents and assume that adequate quality assurance and quality control (QA/QC) measures were followed with regard to sampling, chain of custody, laboratory procedures and data reporting. The validity of the analyses and conclusions drawn for this public health assessment is determined by the completeness and reliability of that information.

A QA/QC program was established for the 1993 RI. The QA/QC program for data collected prior to the 1993 RI is not well defined. The 1993 RI QA/QC program is described in the Final RI report. The purpose of the QA/QC Program was to verify the implementation of procedures and management policies to produce environmental data of known and acceptable quality.

Each contract laboratory used during the RI and SRI was responsible for laboratory quality assurance, complying with all procedures in their laboratory quality assurance manuals, Standard Operating Procedures (SOPs), and the requirements of the NYS DEC Analytical Services Protocols (ASP) Program (NYS DEC, 1989).

D. Physical and Other Hazards

In 1990, and during the 1993 RI, soil gas analysis of the landfill cover was performed by WCCI under the authorization of the NYC DEP. Results indicate that methane gas was detected in concentrations above the lower explosive limit (LEL), oxygen concentrations were too low to sustain human respiration and hydrogen sulfide was detected above the "Immediately Dangerous to Life and Health" (IDLH) Limit of 300 parts per million. Methane levels above the LEL are typical findings for municipal landfills due to degradation or chemical breakdown of municipal wastes. However, these conditions pose occupational hazards for on-site remedial workers who may be exposed to fire and explosion from potential ignition of methane gas. Adherance to the health and safety plan during remediation of the landfill protects workers from potential exposures.

The RI 1993 soil boring sampling indicates that methane is the predominant gas emitted from the landfill at concentrations that are much larger than the detected concentrations of other soil gas emissions. Results of air modeling performed on on-site methane gas emission rates predict that the landfill is responsible for up to 95 percent of methane concentrations found in ambient air in the surrounding communities. Horizontal gas migration and subsequent contaminant soil migration of gases into nearby residences is considered unlikely by the Pelham Bay Science Advisory Committee because of the distance between houses and the landfill. Soil-gas would have to migrate through Pelham Bay Park to reach housing, and currently there is no evidence of stressed vegetation.

Physical hazards typical of construction activities existed on-site for the duration of the current remedial activities. Because the landfill was capped with a gas impermeable membrane, a soil-gas collection system was needed to prevent the buildup of gases. The collected gases are burned in a flare to minimize the potential for the collected gases to contaminate ambient air. Remediation activities included the installation of extraction wells for the collection and subsequent burning of landfill gas emissions, minimizing the potential for on-site physical hazards and migration of gases into ambient air.

E. Toxic Chemical Release Inventory (TRI)

The Toxic Chemical Release Inventory (TRI) has been developed by the US EPA from chemical release information provided by those industries that are required to report contaminant emissions and releases annually. The NYS DOH reviewed air emissions data reported to the TRI by industrial facilities identified to be within a 2.5 mile radius of the PBL site for the years 1988 through 1993. These data were reviewed to evaluate other sources of contamination that may pose an additional health risk to the exposed population at or near the site.

The NYS DOH has developed a screening model to estimate if potential contaminant concentrations resulting from air emissions at a facility may be contributing to community (receptor population) exposures to contaminants at a site. This model uses information about the facility location (distance from the exposed population) and annual air emission data to calculate annual average ambient air concentrations at a distance of 0.5 miles from the site.

Two industrial facilities were identified within a 2.5 mile radius of the PBL site (refer to Figure 8). These facilities are Amsterdam Color Works, Inc. and Absolute Coatings, Inc. The TRI-reports air releases by these facilities for the years 1988-1993 is presented in Table 4.

The NYS DOH uses an air concentration of 1 mcg/m3 as a screening value to evaluate contaminants further. Results of the screening evaluation indicate that TRI-reported air emissions from the facilities identified would not increase contaminant levels in ambient air near the PBL site to levels above this screening criterion. Based on the results of the screening evaluation, the public health significance of contaminant air emissions from TRI facilities as an additional source of community exposures at the PBL site will not be evaluated further in this Public Health Assessment.


PATHWAYS ANALYSIS

This section of the PHA identifies completed and potential exposure pathways associated with past, present, and future use of the site. An exposure pathway is the process by which individuals may be exposed to contaminants originating from a site. An exposure pathway is comprised of five elements, including: (1) a contaminant source; (2) environmental media and transport mechanisms; (3) a point of exposure; (4) a route of exposure; and (5) a receptor population.

The source of contamination is the source of contaminant release to the environment (any waste disposal area or point of discharge). Environmental media and transport mechanisms "carry" contaminants from the source to points where human exposure may occur. The route of exposure is the manner in which a contaminant actually enters or contacts the body (i.e., ingestion, inhalation, dermal adsorption). The receptor population is the person or people who are exposed or may be exposed to contaminants at a point of exposure.

Several types of exposure pathways are evaluated in the PHA; a completed exposure pathway exists when the criteria for all five elements of an exposure pathway are documented; a potential exposure pathway exists when the criteria for one of the five elements comprising an exposure pathway is not met. A suspected exposure pathway is considered to be eliminated when any one of the five elements comprising an exposure pathway has not existed in the past, does not exist in the present and will never exist in the future.

A. Completed Exposure Pathways

Air

Soil gas migration at PBL as determined by the 1993 RI is vertical. Vertical gas migration suggests that on-site workers and trespassers in the past were exposed to site-related contaminants. The receptor population (workers and trespassers) may have inhaled VOCs from the landfill gas and from VOCs volatilized from leachate seeps. However, data are unavailable to evaluate this exposure pathway.

On-site surface soils were found to contain metals and some chlorinated compounds. Past exposure from dust generation most likely occurred when wind blew across unvegetated contaminated soils. Eroded or unvegetated land was mainly confined to the southern portion of the landfill. The remainder of the landfill posed little or no potential for chemical release through fugitive dust generation based on vegetative cover.

Surface Soil

The exposure pathways of concern include past incidental ingestion and dermal contact by on-site workers and trespassers to on-site contaminated surface soils. During the 1993 soil sampling event, soil samples were collected from both the grassy and unvegetated areas of the landfill. Incidental ingestion of surface soil may have occurred as a result of dropping food in soil or through mouth to hand contact with the soils. This is a reasonable exposure pathway for adults and trespassing children.

On-site Garden

In the mid 1980's, a community garden was located on the northwest section (Figure 3) of the landfill and was maintained by local area senior citizens. The garden was closed in 1988. Therefore, these individuals were most likely exposed to soil contaminants by dermal absorption and ingestion of vegetables grown in the landfill's soil. The date the garden first opened is not documented. The 1983 Phase I investigation report references a "small garden".

B. Eliminated Exposure Pathways

Air

The potential for current worker exposure to air borne particulates and VOCs during remediation activities was minimized by an extensive "3" tier air monitoring program. Workers were protected at tier "1"; the exclusion zone. If air quality effects were found in the work zone (tier 1), workers were to follow protective measures detailed in the health and safety plan such as wearing a respirator and protective clothing. If the air quality effects persisted at elevated concentrations, remediation work would be stopped until levels are acceptable. The air monitoring program was in effect throughout the entire process of capping the landfill and included air monitoring at the exclusion zone, landfill perimeter and in the surrounding communities.

A potential exists for site-related air contaminants to migrate off-site into nearby communities. However, with the exception of methane, there is little correlation between landfill emissions and contaminants measured in the community. No differences in contaminant levels between upwind and downwind locations were found which suggests that there are air emission sources other that PBL, since downwind locations from the landfill would have had the highest concentrations of these contaminants if they were coming from the landfill. Ambient air in both the upwind and downwind locations was found to be typical of urban air.

Leachate

There are no present or future exposure pathways associated with leachate contaminants because remedial measures have been taken. These include installation of a leachate collection system to mitigate direct discharge of leachate contaminants into Eastchester Bay and/or the formation of surface seeps, and capping of the site and the installation of a surface water run-off collection system to prevent precipitation from entering the landfill and producing leachate.

Previous site conditions indicate that leachate seeps and leachate run-off occurred. Past exposures to on-site workers and trespassers include dermal absorption and incidental ingestion of contaminants in the leachate. Children may have been exposed while playing around seeps. Leachate contact can occur when walking through seeps or through water run-off after a rainfall. Leachate may be transported from clothing to the skin of both adults and children. Incidental ingestion may occur when contaminated hands and clothing come in contact with food. Because none of the contaminants detected in leachate seeps were found at levels that exceed public health assessment comparison values, this human exposure pathway is not further discussed.

Sediment

During the 1993 RI, sediment samples were taken from areas near the landfill and a reference location. The areas included two sample locations within the beach area just south of the landfill in Pelham Park. The beach is where exposure to contaminated sediment is most likely to occur. Other areas are much less accessible and too soft to stand on. It is reasonable to assume that residents or park users may have come in contact with contaminants in the sediments associated with this beach. Wading and use of the beach have been observed near the landfill within Eastchester Bay. Although dermal contact and incidental ingestion of contaminated sediments by area residents and park users may occur, none of the contaminants detected in sediment samples were found at levels that exceed typical background levels or public health assessment comparison values. Therefore, this human exposure pathway has been eliminated from further discussion.

Fish and Shellfish

Recreational shellfishing in Eastchester Bay is not legal because of microbiological contamination. However, local citizens reportedly collect shellfish in these waters. The NYS DOH and ATSDR staff observed sportfishing during site visits in Eastchester Bay, which is within the immediate vicinity of the landfill. Since groundwater/leachate and sediment have been identified as contaminated, it is reasonable to assume that biota which thrive near the landfill would also be contaminated.

During the 1993 RI, fish and shellfish were collected from three general areas in Eastchester Bay; adjacent to the southern seawall; adjacent to the eastern seawall; and adjacent to Weir Creek (reference station). None of the finfish and shellfish had contaminant levels above US Food and Drug Administration (US FDA) tolerance levels set for their commercial sale, although the levels of cadmium, mercury and lead in the mussels and clams are elevated compared to the results from studies of shellfish from Long Island Sound and the Atlantic Ocean. Because recreational shellfishing is prohibited and there is no permitted commercial shellfishing in Eastchester Bay, consumption of these shellfish is an exposure pathway that should not occur. Because none of the finfish had contaminant levels above US FDA tolerance levels set for their commercial sale, this exposure pathway was not further evaluated. Therefore, the consumption of finfish shellfish is not an exposure pathway selected for further evaluation in the Toxicological Evaluation section of this PHA.

Water Main

There was a water main which ran along the north perimeter of the landfill underneath a dirt road. Surrounding communities were concerned that breaks in the water main would result in contaminated potable water. In response to these concerns, the water main was relocated and repaired during the last stages of site remediation. The water main was relocated so that it now runs parallel to the Shore Road and landfill fence outside of the landfill.

Groundwater

Since the turn of the century, potable drinking water in the New York City area has been provided by a public water supply using surface water from reservoirs located in upstate New York. According to a letter from the NYS DOH to WCCI, dated October 11, 1990, there are no public water system production wells in the Bronx. In addition, there are no known private residential wells near the landfill. Since there are no known private wells within 0.5 miles of the site, which are used for consumptive purposes, it is unlikely that any area drinking water is affected under current conditions.

Exposure to Contaminated Basement Water

Residents from nearby communities that surround the landfill were concerned that residential basements could become contaminated with site-related contaminants after a rainfall. Five basements were sampled which contained water received after a rainfall event. The NYC DEP, NYS DOH, and SAC all concluded that, based on the sampling results, there was no evidence of contamination from the landfill in basement samples. This conclusion was reached because there was no plausible route by which contaminants could have moved from the landfill to the basements and the sampling showed that the type and quantity of indoor air contaminants did not match that in landfill gases or groundwater. Therefore, this exposure pathway is not likely to occur.

Surface Water

In 1988, under the direction of the NYC DEP, surface water in Eastchester Bay was sampled to determine whether the bay was suitable for swimming and recreational purposes. Results of the investigation found that the water was suitable for swimming and recreational use. During the 1993 RI, surface water was resampled and analyzed. Results confirm the findings of the 1988 investigation. Based on the findings of both investigations and the dilution factors associated with large bodies of water, surface water is not considered an exposure pathway of concern.

Indoor Air

During the 1993 RI, an indoor air quality study was conducted by WCCI at the request of the SAC. Results indicate only low levels of VOCs detected in nearby residential homes. These results are typical of low levels of VOCs found in studies by the US EPA on indoor residential quality.


PUBLIC HEALTH IMPLICATIONS (adult and children's health issues)

A. Toxicological Evaluation

An analysis of the toxicological implications of the human exposure pathways of concern is presented below. To evaluate the potential health risks from contaminants of concern associated with the PBL site, the NYS DOH has assessed the risks for cancer and noncancer health effects. The health effects are related to contaminant concentration, exposure pathway, exposure frequency and duration. For additional information on how the NYS DOH determined and qualified health risks applicable to this health assessment, refer to Appendix C.

  1. Past completed ingestion, dermal contact and inhalation exposure to on-site surface soils by on-site workers and trespassers.
  2. In the past, it is likely that workers at the PBL site were exposed to contaminants in on-site surface soils. It is also possible that prior to the site being fenced and capped, trespassers could have come in contact with these contaminated soils. In addition, some people gardened for about five years (1983-1988) on the site and therefore these individuals and their household family members were most likely exposed to soil contaminants primarily by ingestion of vegetables grown in the landfill's soil. On-site soil contaminants selected for further evaluation because they exceed public health assessment comparison values (see Tables 3A and 3B) are the polycyclic aromatic hydrocarbons (PAHs), benzo(a)pyrene (2.8 mg/kg) and benz(a)anthracene (2.0 mg/kg) and the PCB mixture, Aroclor 1254 (1.1 mg/kg).

     

    Benzo(a)pyrene and benz(a)anthracene cause cancer in laboratory animals exposed to high levels over their lifetimes (ATSDR, 1995a). Common cancers associated with exposure to PAHs include skin, respiratory and gastrointestinal tract cancers. Chemicals that cause cancer in laboratory animals may also increase the risk 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, it is estimated that chronic past exposure of workers and trespassers to benzo(a)pyrene found in on-site surface soils at the PBL site could pose a low and very low increased cancer risk, respectively. Furthermore, those individuals who had eaten vegetables grown in soil contaminated with benzo(a)pyrene over a period of about five years could have a low risk of developing cancer. In addition, PAHs cause noncarcinogenic effects, primarily to the immune and blood cell-forming systems. Although the risks of noncarcinogenic effects from exposure to PAH-contaminated soils are not completely understood, the existing data suggest that they would be minimal for both worker and trespasser exposures in the past, as well as for those individuals who ate vegetables grown in on-site soil.

    The other contaminant in on-site soil selected for further evaluation is the PCB mixture, Aroclor 1254. PCBs cause primarily liver cancer in laboratory animals exposed to high levels over their lifetimes (ATSDR, 1995b). Based on the results of animal studies, it is estimated that chronic exposure of those who ate on-site grown vegetables as well as workers and trespassers to PCBs found in on-site surface soils at the PBL site could pose a very low increased cancer risk. PCBs also cause noncarcinogenic toxic effects. Human effects reported after occupational exposures to PCBs include skin, eye and respiratory tract irritation and less frequently, effects on the liver and the nervous and digestion systems (ATSDR, 1995b). There may be a link between a mother's increased exposure to PCBs and effects on her child's birth weight and behavior (ATSDR, 1995b; Rogan and Gladen, 1991, 1992). PCBs have also caused skin, liver, nervous system, immune system and reproductive effects in animals (ATSDR, 1995b). Although the risks of noncarcinogenic effects from exposure to on-site soils contaminated with PCBs are not completely understood, the existing data suggest that they would be minimal for both worker and trespasser exposure as well as for those persons who ate vegetables grown in soil at the PBL site.

B. Health Outcome Data Evaluation

In March of 1988, the NYC DOH received a report from Pelham Bay citizens of 12 cases of leukemia (among other diseases). In response to community concerns, the NYC DOH carried out two major cancer incidence studies concerning Pelham Bay area residents. The first cancer incidence study was performed in 1988, and is titled, "An Evaluation of Childhood Leukemia In The Pelham Bay Area of the Bronx" (NYC DOH, 1988). Based on recommendations by the SAC, additional work was done to address issues raised by the 1988 study. This work is summarized in the 1994 NYC DOH report titled, "Cancer Incidence in the Pelham Bay Area of the Bronx."

The purpose of the 1988 Childhood Leukemia Study was to determine whether a cluster of leukemia cases existed among children living near the landfill. This was in response to the twelve reported cases of leukemia in March of 1988. The study did not attempt to determine the exposure of each case and thus could not assess the likelihood that exposure to the landfill was associated with the disease. A study design was developed to evaluate the incidence of childhood leukemia between the ages of 0 to 14 years of age among Bronx Districts 4 and 6 for the years 1974 to 1985. This study time frame covers the period for which the NYS Cancer Registry, which collects information about all cancers diagnosed within the state, is considered to have complete data (cancer has been a reportable disease in New York City since 1973). To ensure that all cases of childhood leukemia occurring in the Health Districts (HD 4 and HD 6) were accounted for, the New York City DOH requested a listing of all cases of childhood leukemia which occurred during the period 1974 - 1985.

The total number of cases that were documented in the Bronx HD 4 and 6 from 1972 - 1988 were 57 cases (the "observed" cases). Six leukemia types were identified among the 51 cases provided by the NYS Cancer Registry. Of the 51 cases, 37 cases were diagnosed as having acute lymphoid leukemia; two cases were diagnosed as unspecified lymphoid leukemia; seven cases were diagnosed as having acute myeloid leukemia; two cases were diagnosed as having chronic myeloid leukemia; two cases were diagnosed with acute leukemia of unspecified cell type; and one case had leukemia of unspecified cell type, unspecified chronicity.

To evaluate whether the incidence of childhood leukemia in Bronx HD 4 and HD 6 were elevated, NYC DOH did a statistical comparison with the incidence of childhood leukemia in New York City (the "expected" cases). Overall, the cumulative incidence of childhood leukemia in Bronx HD 4 and HD 6 during 1974 to 1985 were not higher than expected. Fifty-two cases were observed while 51 were expected. During the 12 year study period, there was no apparent trend in the observed to expected ratio. The observed to expected ratio in each health district was also analyzed separately. The data did not show a significant elevated increase in cases of leukemia. Leukemia rates may vary by race and sex. Health districts 4 and 6 were stratified (separated) by age and sex, no significant elevation in leukemia cases was observed. Distance to the landfill was also evaluated. The incidence of cancer for populations living within 1, 2, 3, 4, and 5 mile radius from the center of the landfill were calculated. Overall, the incidence of childhood leukemia within each 1-mile band from the center of the landfill was not significantly greater than expected. Thus, the New York City DOH concluded that there is no evidence of an increased incidence of childhood leukemia in the community adjacent to the landfill.

In response to additional community concerns that all cancers should be evaluated to determine whether elevated cases of other types of cancers existed in the community adjacent to the PBL, in 1994 the NYC DOH conducted the Pelham Bay Cancer Incidence Study (9). The NYC DOH evaluated total cancer, 3 specific types in children and 13 specific types in adults during the period between 1978 and 1987.

Among adults, the following types of cancers were analyzed for incidence: pharynx, stomach, colon, pancreas, prostate, bladder, lung, kidney, liver, nervous system, breast (in women), lymphatic system, leukemia and total cancers. Among children (ages 14 and under), the most common types of cancer were: leukemia, nervous system cancers and lymphomas. Included was total cancer incidence. The "Study Area" for the analyses consisted of two health districts located adjacent to the landfill, one to the North and one to the south which included City Island.

A total of 24,025 cases of cancer occurred in the study area during the 10 year period from 1978 to 1987 in a population of 502,915. The most common types of cancer were lung, prostate, and colon in men and breast, colon and lung in women. Leukemia were the most commonly diagnosed cancer in children. These are also the most common types of cancer in New York City, NYS and the United States. For both adults and children, the overall incidence of total cancers and most specific types of cancer in the Study area was similar to New York City. Among men, 11,006 cases were observed while 11,067 were expected. For 10 out of the 12 cancers and all sites combined, the study area was similar to New York City. Among women, 12,883 cases were observed while 12,997 were expected. Each of the 12 cancer types and the incidence of total cancers were similar to New York City. Among boys, 75 cases were observed while 72 were expected. Among girls, 61 cases were observed while 59 were expected. For the children, there were no sites for which there were statistically more cases of cancer observed than expected over the 10 years period.

For eleven out of the 13 types of cancer in adults there was no pattern of either increasing or decreasing incidence based on distance from the landfill. The results of the expanded investigation of cancer among residents of Pelham Bay area of the Bronx are consistent with the 1988 study of leukemia. The results indicate that the total cancer and the incidence of most types of cancers in men, women, and children were similar to New York City. For all sites combined and most cancer (12 out of 13), there was no evidence of increased cancer incidence among residents living closer to the landfill compared with those living further away.

Leukemia, lung, colon and kidney cancer were found to be statistically elevated in the Study Area. However, these findings are not consistent with potential exposures from the landfill contaminants for the following reasons: (1) there are no common mechanisms or exposures known to cause all four cancers. Each cancer has many possible, yet different causes. Lung cancer can be attributable to smoking, exposure to asbestos, radon and others. Colon cancer can be attributable to diet and family genetics (predisposition), for example. Kidney cancer can be attributable to cigarette smoke and obesity. Leukemia have been associated with exposure to chemicals like benzene. (2) There is no pattern of cancer across or within any of the groups across the population. For example, leukemia and colon cancer were elevated in men, but not women. The increase in lung cancer among women is consistent with increase in lung cancer among women in New York City, NYS and the United States. If these cancers were expected to be attributable to the landfill, then one would not expect the effect to be sex specific, since there are no carcinogens known to affect one sex and not another. (3) Current environmental data indicates that there are no significant exposures to area residents from the landfill. There is limited historical exposure data available on the PBL.

In summary, the incidence of cancer in the study area as determined by the 1994 Cancer Incidence Study was similar to New York City for pharynx, stomach, pancreas, lung, prostrate, bladder, kidney, liver, nervous system, breast, lymphatic system, and total cancers. While the study did find an increase in a few specific types of cancers for certain subgroups, there was no evidence of cancer patterns consistent with potential exposures from the landfill. The results of the Cancer Incidence Study conducted in 1994 are consistent with results of Childhood Leukemia conducted in 1988. The NYS DOH and ATSDR conclude, based on the above cancer incidence studies, that the PBL has not caused an increase in the incidence of cancer in the adjacent resident communities. This conclusion was also supported by the Scientific Advisory Committee (SAC).

C. Community Health Concerns Evaluation

The resident community of Pelham Bay is concerned about: (1) exposure to both on-site and off-site contaminants and the potential link to local cases of childhood leukemia and various adult cancers. They also expressed concern about past conditions of the site such as un-authorized entry to the property due to poorly maintained fencing, the existence of leachate seeps, leachate run-off, consumption of fish harvested from Eastchester Bay, and the direct discharge (via french drains) of groundwater/leachate into Eastchester Bay. In February 1989, the Pelham Bay Task Force, comprised of citizens, elected officials, regulatory agencies and New York City, was formed to help identify and address community concerns. The Task Force was also provided funding to assign the SAC to review all scientific issues and investigations concerning PBL. Community concerns via the Task Force and SAC committee members have been represented at all pertinent meetings and scientific investigations that were conducted for the PBL.

In May 1989, Congressmen Ron Wyden and Eliot L. Engel petitioned the Agency for Toxic Substances and Disease Registry (ATSDR) to perform a health evaluation of the Pelham Bay Landfill. The basis for their petition was concern about noxious odors and water runoff from the landfill. They also referenced that local residents reported high incidences of leukemia and autism. All of these concerns were shared by the Pelham Bay Task Force.

Two extensive epidemiology studies and an addendum have been conducted by the NYC DOH Environmental and Occupational Epidemiology Unit. The cancer studies responded to community questions concerning the incidence of various cancers, including leukemia in children and adults in the resident communities as compared to similar communities (New York City).

Remediation of the site has addressed site-related conditions that posed potential health threats. The fence which surrounds the perimeter of the site has been repaired or replaced as necessary. The installation of a leachate collection system including a slurry wall, the 10 inch diameter French drains installed in 1988 and 6 inch diameter French drains installed in 1995, minimizes the formation of surface seeps and the discharge of leachate directly into Eastchester Bay. The installation of extraction wells for soil-gas collection prevents the formation of areas of high methane concentrations. The landfill cap prevents the infiltration of rain water within the landfill and the subsequent formation of contaminated groundwater/leachate. Rain water run-off is collected into holding ponds to allow sedimentation and is eventually discharged into Eastchester Bay. Remediation of the site also includes the installation of a soil-bentonite slurry wall to prevent any groundwater/leachate from migrating to off-site areas. To prevent the buildup and release of methane and other landfill gases, a soil gas collection system and high temperature flare were installed. Monitoring of the performance of the flare in 1997 showed that the landfill gases were destroyed.

Concerns about consumption of fish and shellfish caught from Eastchester Bay are currently being addressed as part of an extensive effort by the US EPA and NYS DOH to inform the public of the NYS DOH consumption advisories. Previous efforts specific to thi site included distribution of the advisory at public meetings on the PBL. The consumption advisories are not specific to Eastchester Bay, but are for marine fisheries in general.

In 1995, the National Association of County and City Health Officials (NACCHO) awarded the NYC DOH funds to conduct an assessment of the educational needs of the community concerning health issues with the landfill. The NYC DOH collaborated with the Mount Sinai Occupational and Environmental Medicine Program to do the assessment and participated in a second grant from NACCHO to fulfill the needs identified. The second grant colminated in a health issues workshop on July 20, 1996.

In review of community concerns the NYS DOH and the ATSDR conclude that (1) community concerns have been addressed, (2) all appropriate protective measures to mitigate exposure have been or are being taken, and (3) remediation at the site is appropriate and protective of on-site workers and adjacent communities.

The public was invited to review the draft during the public comment period, which ran from February 24 to April 14, 2000. We received no comments from residents or organizations. If you have any questions about this public health assessment, you may contact the New York State Department of Health's (NYS DOH) Outreach Unit at the toll free number: 1-800-458-1158.


CONCLUSIONS

  1. Based on ATSDR's present public health hazard category classification (Appendix D), the PBL site posed a public health hazard in the past. Prior to on-site remedial activities, site access was not restricted. In the mid- 1980's, a community garden was located on-site and maintained by local area senior citizens. It is likely that these individuals and other trespassers (including children and the homeless), as well as workers on-site, were exposed to PAHs in on-site surface soil. The NYS DOH estimated that past exposures to PAHs in on-site surface soil could pose a low increased cancer risk to on-site workers and to those persons who ate vegetables grown in this soil.

  2. Currently, the site poses no apparent public health hazard. Remedial actions, including capping of the site and fencing to prevent unauthorized entry onto the site, have minimized the potential for exposure to on-site contaminants.

  3. Off-site ambient air evaluated during the 1993 RI/FS indicate that PBL is not the primary source of VOCs contaminants detected off-site in the community. This also agrees with the results of models based on the emission rates measured at the landfill and was further supported by the results of the Health and Safety air monitoring done from December 1994 to November 1995. Finally, the levels of the VOCs contaminants found were typical of urban centers.

  4. Leachate from the landfill does enter Eastchester Bay. In 1988, the NYC DOH and NYS DOH found that the leachate is diluted to levels that were not a health hazard for bathers. In 1991, the amount of leachate discharged to the bay was reduced by the installation of a leachate collection system.

  5. Potable water is provided by municipal water supplies. Consequently, there is little potential for present or future health threats associated with groundwater/leachate. A 20 inch water main used to supply water to City Island was under the landfill for a short distance. This main was relocated in 1995 from within to outside the limits of the fill of the landfill.

  6. None of the finfish and shellfish had contaminant levels above US FDA tolerance levels set for commercial sale.

  7. The NYC DOH epidemiology studies which were reviewed by NYS DOH and the SAC show no evidence of an overall increase in cancer rates in the neighborhoods surrounding the PB due to the landfill.

RECOMMENDATIONS

  1. No further action in addition to that already planned is needed to address potential off-site contamination of air emissions at the landfill. The PBL was shown to contribute to less than 1 percent of the VOCs detected in off-site air samples. The levels of VOCs found off-site are typical of the levels found in urban environments. The capping of the landfill including the installation of a soil-gas collection and treatment system will further reduce the potential for off-site air contamination.

  2. Operation of the leachate collection system should continue. The operation of this system will further reduce the potential for human exposure to contaminants from the site that are discharged into Eastchester Bay. Reduction in the amount of leachate is also expected because of the landfill capping.

  3. Because groundwater is not used for a potable water supply, no further action is required. However, moving a potable water main which serves City Island from underneath the landfill addressed community concerns.

  4. More effort is needed to educate the public that neither recreational shellfishing nor commercial shellfishing is permitted in Eastchester Bay. If the status changes, contaminant levels in shellfish should be reviewed.

  5. Further effort to inform local citizens of the NYS DOH Health Advisory of Chemicals in Sportfish and Game is recommended. This recommendation is made based on the repeated concern of the Pelham Bay Task Force and NYS DOH staff that the community is not aware of the advisory.

HEALTH ACTIVITIES RECOMMENDATION PANEL (HARP) RECOMMENDATION

The data and information developed in the Public Health Assessment for the PBL site, Bronx, New York, has been reviewed by ATSDR's Health Activities Recommendation Panel to determine appropriate follow-up actions. The community believes that adverse health outcomes seen in the community, specifically childhood leukemia, autism, and multiple sclerosis, may be related to exposure to hazardous substances associated with PBL. HARP has determined that the potentially exposed population(s) need assistance in understanding the pathways by which they have or may have been exposed, the potential for such exposures, and the potential adverse health effects of such exposures. Therefore, both community and health profession education is indicated. The NYC DOH conducted a cancer study to address community concerns with cancer cases other than leukemia. The NYC DEP collected tap water, fish, and shellfish samples in the area adjacent to PBL for the preliminary list of "contaminants of concern" as part of their human and ecological risk assessment for PBL. The data, which ATSDR requested, are part of the remedial investigation (RI) of June 1993. This public health assessment includes the evaluation of that data.


PUBLIC HEALTH ACTION PLAN

In review of current data concerning the PBL, the NYS DOH and ATSDR support the conclusion that PBL does not pose a present or future public health threat to the citizens of Pelham Bay area. However, consistent with public health protective measures, NYS DOH and ATSDR will:

  1. continue efforts to educate the public on the NYS DOH fish advisory in Eastchester Bay

  2. track the status of the site.

PREPARERS OF THE REPORT

Katarina B. Holbrook
School Of Public Health
State University of New York at Albany

and

Lloyd Wilson
Bureau of Environmental Exposure Investigation
New York State Department of Health

and

Joel H. Kaplan
Bureau of Toxic Substance Assessment
New York State Department of Health


REFERENCES

Agency for Toxic Substances and Disease Registry (ATSDR). 1993. Draft Petitioned Health Assessment for the Pelham Bay Landfill, Bronx, New York. July.

Agency of Toxic Substances and Disease Registry (ATSDR). 1994a. Toxicological Profile for 4,4'-DDT, 4,4'-DDE and 4,4'-DDD. Update. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Service.

Agency of Toxic Substances and Disease Registry (ATSDR). 1994b. Toxicological Profile for Mercury. Update. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Service.

Agency of Toxic Substances and Disease Registry (ATSDR). 1995a. Toxicological Profile for Polycyclic Aromatic Hydrocarbons. Update. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Service.

Agency of Toxic Substances and Disease Registry (ATSDR). 1995b. Toxicological Profile for Polychlorinated Biphenyls. Update Draft. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Service.

Agency of Toxic Substances and Disease Registry (ATSDR). 1997. Toxicological Profile for Benzene. Update. U.S. Department of Health and Human Services. Atlanta, Georgia: U.S. Public Health Service.

Edwards, N.T. 1983. Polycyclic aromatic hydrocarbons (PAHs) in the terrestrial environment - a review. J. Environ. Qual. 12: 427-441.

New York City Department of Health. 1988. Results of Beach water and Pelham Bay Landfill leachate Sampling. May.

New York City Department of Health. 1988. An Evaluation of Childhood Leukemia in Pelham Bay Area of the Bronx. October.

New York City Department of Health. 1993. Pelham Bay Cancer Incidence Study. December.

New York City Department of Health. 1994. Pelham Bay cancer incidence Study Addendum. December.

New York State Department of Environmental Conservation. 1986. Division of Solid and Hazardous Waste. Inactive Hazardous Waste Disposal Site Report. March

New York State Department of Environmental Conservation. 1993. Record of Decision. Albany, New York. August.

New York State Department of Health. 1988. Letter to Dr. David Axelrod from Dr. Nancy Kim. Dated July 19, 1988.

New York State Department of Health. 1993. Letter to Mr. Nigel Crawford (NYS DEC) Concerning Draft Remedial Investigation for PBL from Lloyd Wilson. April.

Rogan, W.J. and B.C. Gladen. 1991. PCBs, DDE and child development at 18 and 24 months. Ann. Epidemiol. 1: 407-413.

Rogan, W.J. and B.C. Gladen. 1992. Neurotoxicity of PCBs and related compounds. Neurotoxicology. 13: 27-36.

U.S. Environmental Protection Agency (US EPA). 1993. Provisional Guidance for Quantitative Risk Assessment of Polycyclic Aromatic Hydrocarbons. EPA/600/R-93/089. July 1993.

Woodward-Clyde Consultants Incorporated. 1993. Feasibility Study Report. June.

Woodward-Clyde Consultants Incorporated. 1990. Soil Boring and Monitoring Well Installation, Summary of Activities. January.

Woodward-Clyde Consultants Incorporated. 1993. Remedial Investigation, Baseline Risk Assessment and Feasibility Study. Overhead Projector Slides Presented At Public Meeting on April 28, 1993 at 7:00 P.M.

Woodward-Clyde Consultants Incorporated. 1993. Remediation Investigation/Feasibility Study (RI/FS). June.

Woodward-Clyde Consultants Incorporated.1993. Baseline Risk Assessment. June.

Woodward-Clyde Consultants Incorporated. 1993. Supplemental Remedial Investigation Report. June.


CERTIFICATION

The Public Health Assessment for the Pelham Bay Landfill site was prepared by the New York State Department of Health under a cooperative agreement with the Agency for Toxic Substances and Disease Registry (ATSDR). It is in accordance with approved methodology and procedures existing at the time the public health assessment was initiated.

Gregory V. Ulrisch
Technical Project Officer, SPS, SSAB, DHAC


The Division of Health Assessment and Consultation (DHAC), ATSDR, has reviewed this Public Health Assessment and concurs with its findings.

Richard Gillig
Acting Chief, SSAB, DHAC, ATSDR


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