longhorn army ammunition plant

HWY 43

The site is located between State Highway 43 and Caddo Lake in Karnack, Harrison County, Texas, which is approximately 14 miles northeast of Marshall, Texas, and approximately 40 miles northwest of Shreveport, Louisiana. The site is in a rural area with few residences in close proximity. Approximately 1500 people live within a one-mile radius of the site. The site operated from 1942 to 1997, historically manufacturing TNT, rocket motors and various pyrotechnic items. Site operations included loading, assembling and packing pyrotechnic and signal ammunition, manufacturing solid propellant rocket motors, and rocket demilitarization pursuant to the Intermediate-Range Nuclear Force (INF) treaty between the United States and USSR. The site was finalized on the National Priorities List in 1990 and per the 1991 Federal Facilities Agreement (FFA). The Army conducts environmental investigation and cleanup of LHAAP, with oversight from EPA and the TCEQ. Other agencies involved include the U.S. Geological Survey and the FWS. The Army declared the installation excess to its needs in July 1997. From 1998 to 2001, all personal assets and specific installed property and buildings were liquidated and/or demolished. In Oct 2002, LHAAP was transferred to the Base Realignment and Closure (BRAC) Division to be managed as excess property. On October 19, 2000, the FWS approved the establishment of the Caddo Lake National Wildlife Refuge (Caddo Lake NWR) on LHAAP. In April 2004, the Army and FWS entered into a Memorandum of Agreement (MOA) that sets forth the transfer process of LHAAP acreage. Approximately 7,200 acres out of 8,416 acres have been transferred from the Army to FWS for the Caddo Lake NWR. The Caddo Lake NWR has been opened to the public since September 2009.

Hazardous Ranking Score

40 / 100

A score of 28.5 or higher qualifies a site for the Superfund National Priority List.

Regional Contact

Region 6
Phone: (800) 887-6063

Contact Region



Site Inspection
Preliminary Assessment
Final Listing On NPL

Contaminants & Health Effects

      Endocrine Disrupter
      Reproductive Toxin
      Persistent, bioaccumulative and toxic


        African American
        American Indian and Alaska Native
        Native Hawaiian


        People living
        within a 1 mile radius


        Average Income


        Occupied homes

        Potentially Responsible Parties

        Similar Sites

        Add Story


        No stories have been submitted for this site.