Longhorn Army Ammunition Plant

Environmental Restoration Program

LHAAP-12

Site Description/History

LHAAP-12 was established in 1963, covers approximately seven acres, and is 500 feet southeast of Central Creek, which eventually drains into Caddo Lake. It was transferred to the U.S. Fish and Wildlife Services (USFWS) in March 2014 and is now part of the Caddo Lake National Wildlife Refuge.

LHAAP-12 was used for the disposal of industrial solid wastes, possibly containing small quantities of hazardous constituents generated at LHAAP. From 1978 until its closure in April 1994, the landfill was used continuously for the disposal of non-hazardous industrial solid waste, including cafeteria waste, chemical waste, petroleum-contaminated soil, and asbestos.

Remediation Activities

The construction of a landfill cap over the site was completed in 1998 as part of an Interim Remedial Action (IRA). The IRA is consistent with U.S. Environmental Protection Agency (USEPA) presumptive remedy guidance. The final remedy for LHAAP-12 is protective of human health and the environment and consists of Land Use Controls (LUCs) in conjunction with monitored natural attenuation (MNA). The Final Record of Decision (ROD) was signed in April 2006, and in September 2007 USEPA made a determination that the site was Operating Properly and Successfully. LUCs include landfill cap maintenance and restriction of groundwater use.

Contaminants of Concern

TCE is the primary COC in groundwater

Current Phase

In the Remedial Action Operation phase. Current activities includinge MNA (sampling and reporting), Long-Term Monitoring for groundwater, cap maintenance, well maintenance, inspection, LUC documentation, and reporting, including Five-Year Reviews.

Future Phase

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