Navy OKs environmental cleanup plan at former Carr Point shooting range in RI
By SEAN FLYNN | Newport Daily News, R.I. | Published: December 28, 2020
PORTSMOUTH, R.I. (Tribune News Service) — The Navy and state and federal environmental agencies have agreed on a cleanup and environmental remediation plan for the former Carr Point shooting range.
Naval Station Newport this week made public a 163-page “Record of Decision” that outlines what will be done in the coming years to remove contaminated soil from the site and contaminated sediment offshore, as well as what will be done to protect the groundwater there. The site will be capped with new soil and other materials.
The 4-acre property is off the Defense Highway, better known locally as Burma Road, on the shore of Narragansett Bay. Active and retired military currently use the site as a recreational vehicle campground that has electricity and water hookups for six RVs. It is just south of two ball fields that are on a separate parcel. Lawton Brook is about a third of a mile away to the southeast.
Carr Point was formerly a recreational skeet-shooting range, first used from 1967 to 1973 by Navy personnel and then from 1975 to 1989 by the Aquidneck Island Military Rod and Gun Club, according to the Navy report.
The military personnel used small arms like shotguns to fire at moving targets like clay pigeons over Narragansett Bay. Remains of the target shooting, including concrete pads and walkways, can still be seen at the site. The historical record shows there were three firing arcs on the land, and a fanned out area where the targets and pellets landed has been marked out.
Target fragments and lead pellets are found in the water mainly about 300 feet from the shooting area, but “lead pellet accumulation extends another 600 feet beyond the target area,” says the report.
Pellet counts ranged up to 14,100 pellets per cubic foot in the one-foot depth of bay sediment and up to 10,800 pellets per cubic foot between one and two feet deep.
“Pellets were not found in abundance at locations closest to the shoreline, and none were counted beyond 600 feet from shore,” the report says. These lead pellets are the “primary source of contamination in the sediment.”
Naval Station Newport is undertaking the comprehensive environmental investigation and cleanup of the site under the Navy Munitions Response Program.
There are no buildings on the parcel now, but it once had a Fire House, Fire Auxiliary Headquarters and a Club House, according to historical utility drawings provided by the Navy. The maps show other smaller buildings that are not identified. The Club House, which was demolished in March 2011, was the final building to be removed.
Remnants of the former site use, such as a concrete pad, buried utility lines, a stormwater drain, and utility manholes exist throughout the site, according to the report.
Soil contaminants on the property include polychlorinated biphenyls (PCBs), which were once widely used in the coolant fluids of electrical apparatus, among other uses.
“PCBs present in the soil … are likely from the use, maintenance, and storage of transformers and their waste oils on the site several decades ago,” the report says.
Other contaminants include polycyclic aromatic hydrocarbons (PAHs), which are found in coal and oil deposits and can come from incineration, engines and firing.
“The most elevated concentrations of PAHs are present in soil within the firing arcs, likely due to the dispersion of clay pigeons,” the report says.
The remediation plan calls for the excavation of up to two feet of soil at certain site areas, and up to four feet in one other area.
“Following excavation, the slope along the shoreline will be covered with a geo-textile membrane, soil, and rip rap for stability,” the report says.
The majority of the site will be covered with fresh soil and in a smaller section with asphalt or a similar product.
“Materials for the cover system will be determined during the remedial design and will consist of materials that will allow site reuse similar to existing conditions,” the report says.
“Land use controls will be established to prevent use of the site for residential purposes while maintaining the current recreational use,” the report says. These controls will “require that any future work on the stabilized shoreline slope establish appropriate mitigation measures to prevent migration of contaminants to the offshore area.”
Offshore sediment containing lead pellets also will be removed.
“The remedy may include mechanical screening of some sediment to remove lead pellets, if determined to be feasible in remedial design, to reduce disposal volumes and costs,” the report says. “Lead pellets would be transported offsite for recycling.”
While the Navy, the state Department of Environmental Management and the federal Environmental Protection Agency have agreed on what needs to be done to clean up the former shooting range, there is still work to be done before the excavation and other construction measures begin.
“A pre-design investigation will be completed to further refine the extent of removal,” says the report. “In addition, a submerged aquatic vegetation survey will be conducted to assess if any sensitive aquatic habitats will be altered by the remedy.”
The study of the site has been going on for years and will continue into future years.
“Over the course of the investigation process, the Navy collected nearly 200 soil samples to determine the nature and extent of contamination,” the report says. “Following excavation, the Navy will collect soil samples to ensure that cleanup goals have been met.”
After the planned environmental measures, such as capping with new soil are taken, the ongoing natural remediation of the groundwater will take take approximately 33 years to achieve the required water quality standards, the report says.
Monitoring wells will be installed for additional groundwater sampling and assessment during those years until the water standards are met.
This article originally appeared on Newport Daily News: Navy OKs environmental cleanup plan at former Carr Point shooting range in Portsmouth
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