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Hazardous Waste Cleanup: Naval Weapons Industrial Reserve Plant and Northrop Grumman Corporation Site (NWIRP) in Bethpage, New York

On this page:

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

Cleanup Status 

Northrop Grumman installed and operates an Onsite Containment System (ONCT), located on the southern side of the former Grumman and Navy site to help control off-site migration of contaminated groundwater that is within site boundaries. Although the on-site containment system is removing a considerable amount of contamination, there have been questions regarding the efficacy of its performance in deeper portions of the aquifer. Because of this, the Navy has agreed to construct additional deep profile borings at the on-site containment system to determine whether there may be deep contamination that has not yet been identified.

The Navy began construction of these deeper borings. The New York State Department of Environmental Conservation (NYSDEC) is the lead agency for this facility. Northrop Grumman also began operating a containment system as an interim measure at the southern boundary of Bethpage Park since December 2009, with periodic shutdowns for maintenance. It is too early to evaluate its performance of the containment system south of Bethpage Park. 

Southeast of the site, the Navy constructed an off-site groundwater hot spot remediation system (GM-38 Area) which was completed in December 2009 and is currently in operation. The Navy is planning installation of monitoring wells which will be used to improve the ongoing assessment of the migration of contaminated groundwater. This groundwater monitoring program also contains a program to determine the need for treatment of public water supplies, where necessary.  

Additionally, the Navy has evaluated the technical and economic feasibility of a full offsite and downgradient containment option for preventing the contaminated groundwater from spreading further. The Navy's alternatives analyses report was issued January 2012.

Additionally, on July 27, 2011, the New York State Department of Environmental Conservation and the New York State Department of Health approved the Navy’s Residential Soil Vapor Intrusion Home Evaluation and Residential Summary Report (January – March 2011) for the off-site residential area east of the Navy’s Site 1, the Former Drum Marshalling Area.  Due to vapor intrusion of VOCs east of Site 1, Air Purifying Units (APUs) had been installed on thirteen homes and sub-slab depressurization systems (SSDs) had been installed on six homes. 

Subsequent testing indicated that indoor air and sub-slab concentrations at all homes were now below the NYSDOH guideline values. The conclusion of the report was that the APUs and SSDs could be discontinued at individual homes. This was conditioned on the Navy continuing to operate the existing soil vapor extraction system at Site 1 in order to control the source, and continuing to monitor the vacuum field created in the residential neighborhood on a routine basis." The Navy also plans to expand the soil vapor extraction system to increase the source control efficiency. 

Site Description

The combined Northrop Grumman, formerly Grumman Aerospace, (and former Naval Weapons Industrial Reserve Plant Site Facility is situated on 605 acres in the Town of Oyster Bay, Bethpage, New York. Approximately 105 of the 605 acres are occupied by the Naval Weapons Industrial Reserve Plant, a government -owned, contractor -operated facility.

The Northrop Grumman Corporation was established in the early 1930s, and Naval Weapons Industrial Reserve Plant -Bethpage was established in 1941. Activities conducted at the facility included engineering, administrative, research and development, and testing operations, as well as manufacturing operations for the Navy and the National Aeronautics and Space Administration (NASA).

The facility also had an active airfield. Both Northrop Grumman and the Naval Weapons Industrial Reserve Plant had numerous industrial groundwater supply wells and recharge basins. The manufacturing portion of the Northrop Grumman and the complete Naval Weapons Industrial Reserve Plant facility are now closed.

The facility is surrounded by industrial and commercial facilities along with several residential communities. There are several public and private water supply wells located within a two-mile radius of the facility. All water supplies are drawn from the Nassau-Suffolk aquifer system, which was designated a sole-source aquifer by EPA in 1975.

Contaminants at this Facility

Volatile organic compound, mainly trichloroethylene, tetrachlorethylene, dichloroethylene and vinyl chloride, and chromium contamination at the Northrop Grumman facility entered the groundwater through various source areas. These include recharge basins, sumps, dry wells, spill areas and former hazardous waste storage areas at both the Grumman facility and the adjacent Hooker/RUCO EPA Superfund site. 

Currently, an off-site plume of contaminated groundwater is approximately 3,000-plus acres and extends south of Hempstead Turnpike and it reaches in some areas to a depth of approximately 750 feet below the ground.  Three of the Bethpage Water District’s well fields have been impacted by the groundwater contamination, and consequently treatment of the volatile organic compounds (VOCs) has been in place for over 10 years.  Additionally, the AQUA NY well field has recently been impacted and VOC (Trichloroethene) concentrations are increasing in the well field.

Site Responsibility at this Facility

This is a storage facility permitted under the federal Resource Conservation and Recovery Act (RCRA).  Both the Navy and Northrop Grumman are listed as responsible parties in New York State’s  hazardous waste permit system (6 NYCRR Part 373 ) and are Class 2 inactive hazardous waste sites under  the state’s hazardous waste regulations (6 NYCRR Part 375). As the facility no longer manages hazardous wastes, the hazardous waste permit now covers only the on-site corrective action requirements for cleaning up the area formerly operated by Northrop Grumman.

Groundwater remediation, both on-site and off-site, is being conducted under the authority of the New York State Department of Environmental Conservation’s (NYSDEC) division of environmental remediation (Part 375). In 2001, NYSDEC issued a record of decision that describes the selected remediation plan for the facility. The selected remedy includes a groundwater remedial program and a public water supply protection program. 

A NYCRR Part 373 Permit was issued on March 1, 1992 and expired in 1997. The Permit was extended under the State Administrative Procedures Act until a final decision is made on the permit renewal request. NYSDEC decided not to issue a permit modification until all the soil removal has been completed. On January 30, 2005, Northrop Grumman submitted a permit renewal application to NYSDEC for corrective action activities. The permit was renewed July 7, 2007.