Pelham Bay Landfill (PBL)

May 2012

PBL

Pelham Bay

Landfill

Pelham Bay Landfill Location• The 81 acre 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 – 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.

• 40º 51'23" latitude, 73º 48'52" longitude

Pelham Bay Park Map

View from Top of PBL

Defining a Landfill• A secure landfill is a carefully engineered depression in the

ground (or built on top of the ground, resembling a football stadium) into which wastes are put.

• The aim is to avoid any potential water connections between the wastes and the surrounding environment, particularly groundwater.

• Basically, a landfill is a “bathtub in the ground” and bathtubs can leak in two ways: out the bottom or over the top.

• Typical wastes received at the site included: residential wastes, rubbish, street dirt, construction waste and demolition debris.

Landfill Site

Problem: Leachate• Leachate is the fluid that seeps down through the

wastes to the bottom of the landfill and is collected by a system of pipes.

• The bottom of a landfill is sloped; with pipes laid along the bottom to capture contaminated water and other fluids as they accumulate.

• The leachate is then pumped and treated at a wastewater treatment plant (solids are removed from the leachate and returned to the landfill, or sent to another landfill).

PBL Site Background• Operated by the NYC Department of Sanitation

(NYCDOS) from 1963 until 1978 as a disposal site for mixed municipal waste.

• An elevation of 131 feet (16 stories) with steep slopes that rise to a nearly flat top.

• 2,600 tons of municipal waste

• It is the first of four city landfills that are slated to be permanently sealed by the end of the decade.

NYS DEC PBL Classification

• Inactive Hazardous Waste Sites as a Class 3 in 1983. It is not considered a significant threat to public health.

• 1984 changed to a Class 2a, indicating insufficient data to determine the site's classification

• 1987 site was reclassified to Class 2, indicating the site was considered a significant threat to the environment or public health. This qualified the site for funds from New York State to remediate the site.

Illegal Dumping• Testimony from a driver/dispatcher for the Hudson Oil

Refining Co. indicated that from 1974 to 1980 waste oil, sludges, metal plating shavings, lacquer, and solvents were illegally disposed at several NYC landfills, including the Pelham Bay Landfill.

• Estimated that up to 1.1 million gallons of hazardous waste were illegally disposed at the PBL.

• The contaminants identified during subsequent hearings include: cyanide, heavy metals, volatile and semi-volatile organic compounds.

Community Medical Concerns

• Living less than a mile from the landfill: 25 reported cases of childhood leukemia; 61 of multiple sclerosis; 10, lupus; 9, Hodgkin's disease; 6, rare blood diseases, and a range of birth defects.

• Independent scientists (Pelham Bay Science Advisory Committee) conducted retrospective cancer epidemiology studies that showed no evidence of an overall increase in cancer rates in the neighborhoods surrounding the PBL due to the landfill.

1990 Lawsuit – NYCFA vs. NYC• 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.

The Outcome• A permanent injunction was issued requiring New York City to take

measures to prevent leachate from entering Eastchester Bay.

• 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. Leachate was then 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, 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 .

1993 RI/FS

• A Remedial Investigation/Feasibility Study (RI/FS) was completed in August 1993.

• The selected remedy included: – Capping the landfill– Constructing a leachate collection system– Adding active gas venting – Ongoing Post-closure monitoring

Cover or Cap• “Umbrella over the landfill” to keep water out (to

prevent leachate formation).

• Several sloped layers: – clay or membrane liner (to prevent rain from

entering), – covered by a very permeable layer of sandy or

gravelly soil (to promote rain runoff), – covered by topsoil in which vegetation can root (to

stabilize the underlying layers of the cover).

• If the cover (cap) is not maintained, rain will enter and overflow the landfill

Cap Construction• 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.

Landfill Cap

PBL Landfill Cap

• The landfill cap includes an impervious clay liner, complete with an engineered drainage system.

• This is covered by a layer of clean soil and plants, which is sloped to prevent rainwater and surface water from infiltrating the NHIS and buried trash

Vegetation Cover on Cap

Non-Hazardous Hydrocarbon Impacted Soil Program

(NHIS)

Active Gas Venting

Landfill Gas Flare

In the spring of 1996, a flare became operational to burn the gases from the landfill gas collection system.

Leachate Collection System

Hunts Point Sewage Treatment Plant

PBL Improvements• The landfill has been capped to prevent infiltration

and production of leachate.

• Groundwater/leachate is extracted and conveyed to the Hunts Point Sewage Treatment Plant for disposal.

• Environmental monitoring and maintenance of the cap is ongoing.

• The active landfill gas collection system, which includes a landfill gas flare, is operational.

Leachate Collection Problems

• Underlying rock 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.

Initial Soil Cover Problems• 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.

Additional Remediation Work• The site's 89 acres were covered with soil that has been

tested, treated and seeded. Grass is now growing on the landfill.

• 26 “landscaped islands” were planted. These areas, which were designed to integrate the landfill into its surrounding environment, feature a variety of trees, shrubs and bushes.

• In January 1998, a force main was constructed to pipe leachate from the landfill to the Hunts Point Water Pollution Control Plant for treatment.

• In cases of heavy rain, the force main uses sonar technology to redirect leachate to 120,000 gallon holding tanks on-site. After flows return to normal, the leachate is pumped back to the force main and the Hunts Point Plant.

Groundwater Monitoring PipeA groundwater monitoring pipe stands in the center. The two yellow markers on either side make it more visible so that equipment operators will not run into the monitoring station.

November 19, 2011 Tour

• Marianne Anderson, Pelham Bay Park

• Walked 3.5 mile road to the top and observed Northern Harriers, Red Tail Hawks, and American Kestrails

• “Passive Recreational Use”: bird watching, hiking, and bicycling (because of nature of cap)

•EXTRA SLIDES

1993 Information Release Memo

• IRM for the construction of groundwater extraction wells and leachate storage tanks completed in 1993.

• The first phase of the installation: a slurry wall, construction of a groundwater diversion trench and a leachate collection system was completed in December 1994.

• The second phase: recontouring of the landfill surface, placement of final cover, and the installation of an active gas collection system

Previously Limiting Exposure• 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– (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.

1994 Air Monitoring Program• The air monitoring program was run during the

reshaping of the landfill and placement of the synthetic geomembrane liner, 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.

Site Health Assessment• Leachate seeps and landfill gases are present• 1993 remedial investigation showed that exposure to gases

from the landfill is negligible due to dispersion and dilution. • Potential public exposures to leachate and soil-gas have

been limited futher by the construction of the landfill cap and the installation of leachate and soil-gas collection systems.

• Samples of shellfish and finfish were collected from Eastchester Bay in 1993 and the results were not significantly different from fish gathered from other nearby areas.

• The NYSDOH has a issued a fish advisory for Long Island Sound west of Wading River.

• The landfill cap consists of four layers, listed here from bottom to top: – 1) the NHIS final grade, – 2) a geosynthethic clay liner, – 3) a drainage layer, and – 4) three feet of soil with low-rooting vegetation

planted on the surface of the Closed Active Area. – NHIS.

NYS DOH 1986 Site Visit • (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 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.

• 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.

• 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

Community Health Concerns• (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.

1990 Air Monitoring Program• 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.

Soil Gas Samplimg• 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.

• 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 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.

• Pesticides were detected in seven of the 12 monitoring wells sampled quarterly in 1990.

• 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.

• 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".

• 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).

• 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).

• 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.

• 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.

• 1990 Census: NYS DOH estimated that 26,954 people live within one mile of the PBL.

• Land in the immediate vicinity of the landfill is predominately used for residential and transportation purpose

• 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

Contaminants of Concern

Type of Waste Quantity

ALKYL PHENOL UNKNOWN

CYANIDES (SOLUBLE CYANIDE SALTS) 1000000.00

DICHLOROBENZENE (MIXED) UNKNOWN

DIOCTYLPHTHALATE UNKNOWN

ETHYLBENZENE UNKNOWN

NAPHTHALENE UNKNOWN

TOLUENE UNKNOWN

XYLENE (MIXED) UNKNOWN