The Naval Security Group Activity site covers 2,200 acres in Sabana Seca, Puerto Rico, and operated as a naval communications station. From the early 1950s through 1979, the facility's Public Works Department and pest control shop disposed of waste paints, solvents, waste oil, battery acid, and pesticides in ways that allowed chemicals to soak directly into the ground. Those practices contaminated soil and groundwater with arsenic, lead, and chlordane. Gamma-chlordane is the identified contaminant of concern, found in sediment and soil at Site 6, which is Operable Unit 2. EPA flagged it because it poses an unacceptable risk to human health and the environment based on the amount present and its potential health effects.
The site was added to the National Priorities List in 1989. Cleanup was organized into four operable units covering different parts of the property. Remedial investigations started in 1992. In 1988, before the formal cleanup plan was finalized, the Navy fenced the former pest control shop area to stop people from coming into contact with contaminated soil. The main cleanup decision for Site 6 came in September 1996 and called for an engineered cap and revegetation. Workers installed an asphalt cap over the pesticide shop area in 1997, and that area is now used for parking. For the remaining operable units covering Sites 1, 2, 3, 4, and 5, EPA determined in September 1997 that no further action was needed.
All physical construction finished by September 30, 1997. EPA confirmed that human exposure is under control, with no unacceptable exposure pathways remaining. Groundwater migration is not a concern at this site. The site reached Sitewide Ready for Anticipated Use status on June 9, 2006, meaning all cleanup goals for current and expected future land uses have been met and all required land-use controls are in place. EPA deleted the site from the National Priorities List on October 7, 1998.
Because this is a federal facility, the Navy, as owner and operator, holds primary responsibility for cleanup and community involvement. EPA serves as the lead regulatory agency under CERCLA, the Comprehensive Environmental Response, Compensation, and Liability Act. Community members with questions can reach EPA's Remedial Project Manager or Community Involvement Coordinator. The Administrative Record for the site is also available through the lead agency or the site's Public Information Repository.
