SWMU 42 – Water Purification Plant Lagoons

Two clay-lined water purification plant lagoons are used for disposal of sludge from the water purification plant located immediately adjacent to the lagoons to the southeast. The fenced-in lagoons are utilized on a limited basis due to the decreased amount of water being treated and utilized at the facility since the operational closure of Naval Station Roosevelt Roads on March 31, 2004 and the transition of the facility into caretaker status. Each lagoon is mounded above the existing grade and the area to the north and west of the lagoons is classified as Palustrine Emergent Persistent wetland. The sludge, consisting of river mud, aluminum sulfate, and lime, is periodically (approximately every 7 years) removed and disposed of at the base landfill. The water from the lagoons was originally discharged into the nearby creek, rerouted back to the reservoir in the late 1970’s, and routed to the Bundy WWTP between 1995 and 1996, due to the inability to meet the new trihalomethane rule. There is no indication of hazardous wastes being managed and no visual evidence of releases of hazardous wastes or constituents at this SWMU. NAPR has verbally indicated it has no knowledge or evidence of systematic and routine releases of hazardous wastes or constituents from this unit.

Status

• A Revised Final Phase I RFI Work Plan was submitted to EPA for approval on October 11, 2006.
• EPA approved the Phase I RFI Work Plan on October 20, 2006.
• The Phase I RFI field work was conducted between November 10 and November 20, 2006.
• The Revised Final Phase I RFI Report was submitted on January 25, 2008 and accepted by the EPA on February 26, 2008.
• SWMU 42 is recommended for Corrective Action Complete with Controls for removal of the sludge from the lagoons when the water purification plant ceases operation.