Jump to main content.

Naval Weapons Industrial Reserve Plant

Other (Former) Names of Site: Northtrop Grumman, Grumman Aerospace

EPA Identification Number: NYD003995198
Facility Location: Grumman Boulevard, Calverton, New York

Site Map

Facility Contact Name: James Colter, US Navy, (610) 595-0567
EPA Contact Name: Ellen Stein, (212) 637-4114, stein.ellen@epa.gov
New York State Department of Environmental Conservation (NYSDEC) Case Managers: Henry Wilkie, (518) 402-8594, hjwilkie@gw.dec.state.ny.us
Larry Rosenmann, (518) 402-8594, larosenm@gw.dec.state.ny.us
Last Updated: January 2006
Environmental Indicator Status: Human Exposures Under Control [PDF 359.49 KB, 30 pp] has been verified.
Groundwater Contamination Under Control [PDF 15.71 KB, 31 pp] has been verified.

Site Description

The Naval Weapons Industrial Reserve Plant (NWIRP) is located on Grumman Boulevard in Calverton, New York. The facility is bordered by Middle County Road (route 25) to the north, agricultural land to the east, River Road to the south, and Wading River Road to the west. The surrounding area is rural.

The plant was built by the U.S. Navy in 1954, and has been operated by the Northrop Grumman Corporation (formerly Grumman Aerospace Corporation) for the Navy, and originally comprised approximately 6,000 acres. Activities at the plant included assembling, flight testing, refitting, and retrofitting naval aircraft. Northrop Grumman operations ended in February 1996.

In September 1998, about 2,640 acres of the developed property were transferred to the Town of Riverhead for redevelopment. A year later, approximately 2,935 acres of undeveloped land from the site were transferred to the New York State Department of Environmental Conservation (NYSDEC) for wildlife management, and 140 acres were transferred to the U.S. Department of Veterans Affairs for expansion of the Calverton National Cemetery. The remaining 358 acres are still owned by the U.S. Navy, and are undergoing remedial actions.

The plant currently consists of five separate parcels totaling approximately 358 acres. These five parcels consist of:

Site Responsibility and Legal Instruments

The New York State Department of Environmental Conservation (NYSDEC) Division of Solid and Hazardous Materials has primary responsibility for oversight of the Navy's remedial actions. NYSDEC reissued a Corrective Action Part 373 permit to the Navy on April 24, 2000. This permit supersedes and replaces the original Part 373 permit that was issued to Grumman Aerospace Corporation and the Department of the Navy on March 25, 1992.

The new permit, issued only to the Department of The Navy, deals exclusively with those solid waste management units (SWMUs) that remain on the former Navy-Calverton property and any corrective actions that may be required to adequately address each Solid Waste Management Unit (SWMU. The site also is listed on the NYSDEC Registry of Inactive Hazardous Waste Disposal Sites.

Permit Status

NYSDEC's Corrective Action Part 373 permit, reissued on April 18, 2000, is in effect for this facility. It covers only Resource Conservation and Recovery Act (RCRA) corrective action activities. There are no longer any operating waste management units at this facility.

Potential Threats and Contaminants

Please note that not all of the contaminants are present in all of the sites (aeras) listed below, and that at some of them, contaminants have been found at concentrations above standards for soil but not for groundwater. For more detailed information, please refer to the Site Repositories cited below.

Potential Threats From Contaminated Groundwater
Contaminants found in groundwater - metals, PCBs and other semivolatile organic compounds (SVOCs), pesticides, and volatile organic compounds (VOCs).

The site is located above the Long Island groundwater aquifer, which serves as the sole source of drinking water for Long Island. Additionally, the contaminated groundwater may leach into adjacent surface waters and the bottom sediments of these waters. There is evidence that groundwater contamination has migrated off-site from sites 6A and 10B to the southern area. Water supply wells that have been impacted by this contamination are not used for drinking water. Recent hydrogeologic investigations have demonstrated that the low levels of contamination that may be present in groundwater do not migrate beyond the Peconic River. Further, due to natural attenuation, these levels pose no environmental threat. In the recently completed groundwater investigation, contamination was not detected in the river.

Potential Threat from Contaminated Surface Water
There are no contaminated, on-site surface water bodies that pose a threat to human health or the environment. McKay Lake, a man-made basin, received non-contact cooling water as well as treated industrial and sanitary wastewater from the facility. Grumman tested the water in McKay Lake and determined it did not pose a threat to human health or the environment. NYSDEC and EPA concur with this determination.

Potential Threat from Contaminated Soil and Sediments
Contaminants found in soil: metals, polychlorinated biphenyls (PCBs) and other semivolatile organic compounds (SVOCs), pesticides, volatile organic compounds (VOCs).

Contaminants found in sediments: pesticides, PCBs, and lead.

No threat is anticipated from contaminated soil or sediments. Any future soil excavation would be performed in a manner that would minimize exposure to workers. Trespassers are kept off the site by a combination of fencing and security, and are not expected to come in contact with contaminated soil.

Potential Threat from Air Contamination
Although there is groundwater contamination at the site, all of the known groundwater contamination is moving away from the occupied buildings, so indoor air impacts from groundwater vapor intrusion are expected to be limited. However, due to the presence of groundwater contaminated with VOCs and large expanses of pavement adjacent to the areas of concern, EPA in conjunction with the DEC, New York State Department of Health, and the Suffolk County Department of Health Services, conducted an independent study of soil gas and indoor air in the spring and summer of 2004, in the vicinity of Sites 6A and 7.

Although some low levels of contaminants were found in the soil gas and indoor air, it was determined that the detected contaminants were either:

Accordingly, the Agencies determined that, under current conditions, soil gas is not currently having a significant impact on the indoor air quality of buildings and that no complete exposure pathway exists at this time. Any impacts to air in offsite buildings would be unlikely, because a layer of clean groundwater overlies the known offsite groundwater contamination.

A determination that current human exposures are being controlled (a positive human exposures determination) was made in September 2004.

Cleanup Approach and Progress

Site 1 (Northeast Pond Disposal Area)
The Navy has excavated landfill material along with impacted soil and sediment. The Navy removed and disposed of approximately 50,000 cubic yards of fill material and approximately 1500 cubic yards of sediment to an off-site approved disposal facility. The majority of the excavation area was returned to approximately how it was before the landfill existed, and it was revegetated with grass. Cleanup was completed by the summer of 2003. Groundwater monitoring has been discontinued because contamination has not been found above drinking water standards at the boundaries of Site 1.

For further details on the cleanup approach for this area, please refer to:

Site 2 (Fire Rescue Training Area)
A pilot-scale air sparging/soil vapor extraction (AS/SVE) system was installed at the fire training area in 1995 to treat contaminated soil and groundwater. As of the year 2000, approximately 80 pounds of target volatile organic compounds (VOCs) had been removed. The volume of contaminated soil has been reduced significantly by operation of the AS/SVE system. To complete the soil cleanup, the Navy plans to remove the concrete fire training ring and any contaminated soil that may exist above or below the ring, during the year 2006.

For further details on the cleanup approach for this area, please refer to:

Site 6A (Old Fuel Calibration Area)
A groundwater recovery unit was installed in 1987. This unit included a pumping well, an oil recovery well, and an oil/water separator tank. Active groundwater and free product extraction continued until 1993. Passive product recovery (via removal of spilled fuel oil from the top of the groundwater) continued until 1996. A pilot study was conducted for a Vacuum Oil Skimming Unit in September 1999. The pilot operation did not succeed because the volume of product available for recovery was too small and inconsistent for this type of system. Passive free product recovery was restarted in 2000 and continues today, effectively controlling free product quantities at the site.

In 2005, the Navy conducted an extensive hydrogeologic investigation to define the extent of contamination beneath site 6A and the direction of deep groundwater flow. This study showed that the concentration of volatile organic compounds (VOC) contamination beneath Site 6A (Old Fuel Calibration Area) has decreased significantly since 1994. The horizontal extent of contamination is limited and does not extend to the nearest downgradient monitoring wells at the site. Vertically, the contamination is generally limited to the shallow groundwater flow zone that overlies a silty clay layer 60 feet below the ground surface. The groundwater flow in the deep zone is generally towards the east and northeast. Contaminated groundwater that migrates into the southern area is found in discontinuous pockets that are attenuating via natural processes and ultimately discharge to the Peconic River at levels that have no discernable impact upon the river. (Please see the discussion of the Southern Area toward the end of this Fact Sheet.)

For further information regarding the remedy for Site 7, please refer to the following:

Site 7(Fuel Depot Area)
As an interim measure, floating free product (spilled fuel oil that had accumulated on top of the groundwater) was recovered from the groundwater for several years until 1995, at which time the U.S. Navy determined that a separate floating free product layer could no longer be identified. The proposed final remedy is a combination approach consisting of source removal of volatile organic compounds (VOCs) in groundwater using an air sparging/soil vapor extraction technology followed by monitored natural attenuation for the remainder of the low-level VOC groundwater plume, as well as institutional controls (such as development restrictions).

The Navy constructed a pilot Air Sparging/Soil Vapor Extraction system for the site, which operated on a pilot scale from March to July 2005, and is scheduled to become full scale during spring 2006. The full scale air sparging/soil vapor extraction (AS/SVE) process is scheduled to operate for approximately four years. If after four years of operation, groundwater cleanup is not complete or contaminant removal is not working efficiently, the remedy for the residual contamination would most likely be institutional controls and monitored natural attenuation. An assessment of the effectiveness of monitored natural attenuation by the Navy has been performed at this Site, and the preliminary conclusion is that it can be a viable option.

For further information regarding the remedy for Site 7, please refer to the following:

Site 9 (Electronic Counter Measures (ECM) Area)
Low concentrations of contaminants were found in the soil, and low concentrations of volatile organic compounds (VOCs) were detected in the groundwater at the site and off-site. A small amount of contaminated soil was removed as an interim corrective measure. No further soil contamination remains at this area. Trichloroethane (TCA) was found in groundwater at a concentration of 21 ppb immediately off-site from the ECM area and a concentration of 75 ppb approximately 270 feet off the property boundary. As the concentration is increasing with distance, the ECM area is not thought to be the source of this groundwater contamination, and, in any event, is not a continuing source of the contamination.

To confirm this conclusion, several wells were installed downgradient of Site 9 at the property boundary. As part of the Phase 2, Extended Site Investigation, two onsite monitoring wells were installed in 1997 and 11 off-site monitoring wells were installed in 2000. The maximum concentration of TCA detected in these wells was 2 ug/l, which is lower than the New York State drinking water standard for TCA.

For further information regarding Site 9, please refer to the following:

Site 10 A (Jet Fuel Systems Laboratory)
This area was used for testing of fuels and fuel systems. Several underground storage tanks, which have been removed, were located behind the laboratory. Petroleum contamination was found in the soil and fuel-derived volatile organic compounds (VOCs) were found at the soil/groundwater interface. Groundwater contamination with Freon (1100 ug/l) and xylenes (99 ug/l) has been found at an adjacent area, but that source may be Site 7 (the Fuel Depot Area).

Starting in 1993, Northrop Grumman conducted floating free product (jet fuel) recovery from the groundwater at this site. This continued until early 1996. Currently, the area is retained as Navy property and it is enclosed by a fence. No human exposure pathways are believed to exist.

For further information regarding Site 10A, please refer to the following:

Site 10B (Engine Test House)
From the late 1980s to the early 1990s, groundwater from Site 6A was discharged into a drainage swale and culvert adjacent to Site 10B. This is thought to be why Site 10B is contaminated with chlorinatedvolatile organic compounds (VOCs). Site 10B also is contaminated with fuel-derived VOCs, probably due to a leaking underground storage tank that has been removed. Recent groundwater investigations have shown that VOC concentrations have decreased significantly since 1994. In addition, the vertical extent of VOC contaminated groundwater is limited by a silty clay layer to approximately 60 feet below ground surface. Off-site migration does not extend beyond the Peconic River and does not pose a threat to human health and the environment.

For further information regarding Site 10B, please refer to the following:

Southern Area
Contaminated groundwater has been found in the past in this off site area with volatile organic compounds (VOCs) at concentrations as high as 220 ppb (drinking water standards are 5ppb), most likely due to overland flow from sites 6A and 10B. Water supply wells that have been impacted by this contamination are not used for drinking water. Recent hydrogeologic investigations have demonstrated that a silty clay layer limits the vertical extent of VOC contaminated groundwater to approximately 130 feet below ground surface. This groundwater then discharges to the Peconic River. Contaminant concentrations in this groundwater are actively being reduced by natural attenuation so that they are below detection levels in the River and do not pose a threat to human health or the environment. The Navy is currently preparing a Corrective Measures Study to determine which remedial alternatives are appropriate for this area.

For further information regarding the Southern Area, please refer to the following:

Rylinski's Farm (Agricultural Outlease Area)
Soil contaminated with pesticides, as a result of pesticide storage for farming operations, has been removed from approximately five acres of land. Pesticide concentrations in the soils are now below NYSDEC guidance levels. No further action is needed.

For further information regarding the Agricultural Outlease Area, please refer to the following:

Environmental Indicator Status or Projection


Site Repositories

Copies of supporting technical documents and correspondence cited in this site fact sheet are available for public review at:

Division of Solid & Hazardous Materials
Bureau of Solid Waste and Corrective Action
625 Broadway
Albany, NY 12233-7255

The New York State Department of Environmental Conservation (NYSDEC) makes its public records available for a review under the Freedom of Information Law (FOIL).

Riverhead Free Library
330 Court Street
Riverhead, NY 11901


Jump to main content.