Toxics Cleanup

Portsmouth Naval Shipyard Toxics Cleanup

Superfund toxics cleanup at the Portsmouth Naval Shipyard is an ongoing project. SAPL continues to work with and help oversee the process as a community consultant through the Environmental Protection Agency’s TAG Program.

Contaminants at the Shipyard include mercury, benzene, thallium, PCBs, PAHs, dioxin, arsenic, lead, and others. They are found in varying locations including ground water, soil, and sediment. All of these contaminants are being addressed by the cleanup process.

PNSY Toxic Sites Map, image courtesy of the US Navy

PNSY Toxic Sites Map, image courtesy of the US Navy

(from the online EPA Summary)

From 1945 to 1975, untreated acidic and alkaline wastes, waste battery acid and lead sludge, wastewater and spent baths from an electroplating operation, and other wastes from various industrial shops were discharged into the Piscataqua River via industrial waste outfalls. From 1945 until about 1978, 25 acres of tidal flats between two of the islands were filled with wastes, including chromium-, lead-, and cadmium-plating sludge; asbestos insulation; volatile organic compounds (VOCs); waste paint and solvents; mercury-contaminated materials; sandblasting grit containing various metal wastes; and dredged sediments from the Piscataqua River.

In the late 1970s, dredged sediment samples collected near the industrial outfalls were found to be contaminated with elevated concentrations of metals, polychlorinated biphenyls (PCBs) and other contaminants. The Navy has indicated that the probable source of the sediment contamination is the industrial outfalls at PNS.

The site’s long-term remedy includes capping of the Storage Yard, stabilizing the shoreline, removing underground storage tanks, and removing the mercury burial vaults. Work is currently underway at seven areas at the site. In addition, preliminary evaluations of several Screening Areas are determining whether a remedial investigation should be performed at these areas. Monitoring of the Off-Shore Areas sediments and biota is ongoing. All of the site’s remaining areas are in the remedial investigation /feasibility study phase of work. In the Superfund process, a site’s remedial investigation identifies the nature and extent of a site’s contamination, while the feasibility study evaluates various remedies to address the contamination

Our work with the Shipyard is funded in large part by a Technical Assistance Grant from the EPA. Technical Assistance Grants (TAG) help communities participate in Superfund cleanup decision-making. It provides funding to community groups like ours so that we’re able to contract our own independent technical advisor to interpret and explain site conditions, technical reports, and the EPA’s cleanup proposals and decisions. SAPL’s TAG funding has recently been renewed, allowing us to continue our work.


With sea level rising at an accelerating rate, coastal military installations are increasingly exposed to storm surge and tidal flooding. The Union of Concerned Scientists (UCS) conducted analyses of this changing exposure for 18 installations along the East and Gulf coasts. Analysis for Portsmouth Naval Shipyard found that in the second half of this century, in the absence of preventive measures, the installation can expect frequent and extensive tidal flooding, loss of currently utilized land, and substantial increases in the extent and severity of storm-driven flooding to which it is exposed.

Read the UCS factsheet on Coastal Flooding at the Shipyard »

While the Shipyard sees little tidal flooding today, low-lying areas of coastal New Hampshire and southern Maine are already experiencing an increase in tidal flooding. If the rate of sea level rise this century continues to increase, extreme high tides could eventually bisect the shipyard.