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Hazardous Waste Cleanup: Wyeth-Ayerst Laboratories in Pearl River, New York

On this page:

  • Cleanup Status
  • Site Description
  • Contaminants at this Facility
  • Site Responsibility

Cleanup Status 

The closed landfills were investigated during the Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI) and found to have contaminated groundwater flowing under them. Wyeth-Ayerst is implementing a three year natural attenuation and monitoring program, with the intention of demonstrating that the groundwater contamination will meet the State's protective standards before reaching the property line of the facility. Actual groundwater data for the first year verifies this conclusion.

A number of interim corrective measures (ICMs) have been implemented at the site: eight hazardous waste above-ground storage tanks were closed in 2002, including two 100,000-gallon spent combined-acid filtrate tanks and their bottom sludge; removal of 598 tons of discolored soil in the vicinity of the tanks contaminated with methyl isobutyl ketone (MIBK); an ICM program repaired or replaced 9,200 feet of ruptured underground sewers servicing production and pilot plant buildings, by placing new plastic piping inside the old pipeline, and excavating and removing several severely damaged sections of sewer pipe.

In April 1998 the facility discovered a mercury spill of unknown origin while doing routine maintenance outside a building. An ICM removal action was immediately implemented, and 144 cubic yards of mercury-contaminated soil were excavated and replaced with clean fill. The contaminated soil was sent off-site for mercury recovery.

 Site Description

The plant is located on 401 North Middletown Road in the village of Pearl River on a 580-acre site that lies within Clarkstown and Orangetown in Rockland County, New York. The facility is located about 1.5 miles north of the New Jersey State border and 20 miles northwest of New York City. It is bounded by Middletown Road on the East, Crooked Hill Road to the south, and forested and residential areas to the west and north respectively.

The facility produces pharmaceutical products, generating hazardous wastes (e.g., spent solvents, toxic and mixed wastes) and large quantities of nonhazardous solid waste (e.g., incineration ash, composting and wastewater sludge) in the process. Hazardous wastes are stored in 250 55-gallon containers on-site. Releases of contaminants have occurred from the leachate generated at landfills, the burning of solvents in an open pit, leaks of industrial wastewater from underground sewers, and chemical spills.

There are four landfills at this site (1, 2, 2A, and 3A). Landfills 1, 2, and 2A received a mix of waste including incinerator ash, glass, debris, plant trash and rubbish, vitamins, wastewater treatment plant sludge, fermentation cake, animal remains, and small quantities of laboratory chemicals. These three landfills were closed in early 1980 and they were covered with a relatively low permeability material to prevent water seepage. However, groundwater monitoring indicates that releases of organic contaminants have occurred from these units. Landfill 3A, which remains open, receives solid waste generated onsite and operates under a New York State Part 360 Solid Waste Management permit.

The landfill area is in the western portion of the facility, adjacent to Muddy Creek, which bisects the Wyeth-Ayerst facility, flowing into the Pascack Brook and then discharging into the Hackensack River. The nearest New York State regulated freshwater wetland is located about 1.5 miles northwest of the site.

Contaminants at this Facility

The company conducted soil and sediment investigations as directed by the permit. Contaminated soils and sludge were removed from the facility. Investigation of the other Solid Waste Management Units (SWMUs) at the facility indicated that there were no releases that exceeded the relevant action levels established by the New York State Department of Conservation (NYSDEC).

The facility is bounded by a fence to prevent unauthorized entry. The New York State Thruway runs along the southern boundary of the facility where the plume of groundwater contamination exists. Pedestrian traffic on that limited access highway is not permitted, thus further restricting access to the contaminated groundwater. Institutional controls (deed restrictions) have been implemented to ensure that the area in the vicinity of the former impoundments remains undisturbed.

Data collected under the groundwater monitoring program indicate that the plume of contaminated groundwater is limited to the site (that is, does not flow off-site). 

Responsibility at this Facility

A NYS Part 373 hazardous waste permit was issued September 28, 1993 and expired September 29, 1998. This permit has been extended as required by State law and will stay in effect until issuance of the renewal permit.

On July 2015 a NYS Part 373 hazardous waste permit was terminated and all units at the site were clean closed. The site location was sold to Pearl River Campus, LLC on November 11, 2015. Wyeth leased several buildings at the location and operates as a large quantity generator with less than 90 days exempt storage.