Contamination from paint, blasting and other activities will finally be cleaned up at the Naval Submarine Base-New London Superfund Site in Groton, CT, under a Navy plan newly approved by the U.S. Environmental Protection Agency.
|From 1957 to 1973, VOCs, pesticides, polychlorinated biphenyls (PCBs), spent battery acids, and other wastes were buried below the water table at a base landfill.|
The EPA has signed off on a 525-page Final Record of Decision for the site, which is under the jurisdiction of the Naval Facilities Engineering Command (NAVFAC). The final ROD was the 13th submitted in the case.
The site has been on the federal Superfund list for 22 years.
The approval allows the Navy to move forward on remedial design and cleanup action in the area known as the Lower Submarine Base. Cleanup is expected to begin in November 2013.
Painting, blasting and other maintenance activities at the base’s former marine railway are among the primary sources of contamination of the 102-acre Lower Submarine Base, according to the ROD.
Painting activities led to lead and other chemical contamination. Other sources of contamination include lead acid battery maintenance and overhaul, and incinerator operations.
Investigation and Information
In 2011, the Navy completed a remedial investigation of the Lower Submarine Base to define the cause and extent of contamination, which affected the soil, sediment, surface and groundwater. Contaminants in that area included polyaromatic hydrocarbons (PAHs), polychlorinated biphenyls, lead, metals and pesticides.
U.S. Navy photo / William Kenny
|Seaman Apprentice Marshall Harris repairs a simulated engine room leak in the school's damage control wet trainer at Naval Submarine Base-New London.|
Specifically, PAHs, lead and mercury were found at elevated concentrations in the soil. The EPA concluded leaks of petroleum products from fuel distribution lines leaked PAHs into the soil. Volatile Organic Compounds and semi-volatile organic compounds were detected in the base’s groundwater. Concentrations of arsenic, copper and lead also were found.
Based on those findings, the Navy considered various cleanup options, then held a public meeting and public hearing earlier this year. The Navy provided a formal response to the public comments on the cleanup plan in the Record of Decision.
Focus on Soil, Sediment Toxins
The cleanup plan in the Lower Submarine Base will focus on contamination in soil and sediments.
The Navy proposed no action for the area’s surface water and groundwater, saying the regulated contaminants in that area were at very concentrations that did not pose an unacceptable health or ecological risk. EPA officials agreed with the assessment. In addition to this federal cleanup, the Navy will also will clean up state-regulated petroleum wastes within the area.
The Lower Submarine Base area is divided into seven zones, and various remedies have been chosen to clean up the different areas. The remedies include land-use controls, monitoring, sediment dredging, and excavation.
About the Base
The New London Submarine Base site covers 576 acres on the eastern bank of the Thames River in Groton. The base was established in 1868, and has been an operation and support base for submarine activities in the Atlantic Ocean since 1916.
From 1957 to 1973, VOCs, pesticides, polychlorinated biphenyls (PCBs), spent battery acids, and other wastes were buried below the water table in the 11-acre Area A Landfill, which is situated adjacent to wetlands, according to the EPA’s Waste Site Cleanup Fact Sheet.
After contamination was discovered at the Base, the base was listed on EPA’s National Priorities List in August 1990 for cleanup under Superfund program. After that, the EPA, the state of Connecticut, and the Navy signed a formal agreement known as a Federal Facility Agreement, which is a procedural framework for addressing cleanup at the site.