Longhorn Army Ammunition Plant

⚠ Superfund · Cleanup underway

Longhorn Army Ammunition Plant (LHAAP) is broken down into various operable units (OU) that are in different phases of the CERCLA processes. The US Army is the lead agency tasked with the remediation of the Longhorn Army Ammunition Superfund site. The EPA along with TCEQ provide regulatory oversight to all activities conducted at the LHAAP site.

Location

CityKarnack
CountyHarrison County
StateTexas
Coordinates32.66500, -94.12334

Contaminants of concern

Contaminated media

Cleanup timeline

  1. Initial Assessment Completed — 03/01/1984
  2. Proposed to the National Priorities List — 07/14/1989
  3. Finalized on the National Priorities List — 08/30/1990
  4. Remedial Investigation Started — 10/16/1991
  5. Remedy Selected — 05/12/1995
  6. Final Remedy Selected — 02/25/2020
  7. Remedial Action Started — 10/25/1996
  8. Final Remedial Action Started — Estimated Oct - Dec 2026
  9. Construction Completed — Not Yet Achieved
  10. Deleted from National Priorities List — Not Yet Achieved

EPA references

Understanding this Superfund site

Longhorn Army Ammunition Plant is a federal Superfund site in Texas. The Superfund program, created by Congress in 1980, addresses sites where hazardous substances have been released or threaten release into the environment. EPA scores potential sites using the Hazard Ranking System; those that score high enough are placed on the National Priorities List.

Current status: Cleanup underway. Active cleanup is underway, meaning EPA has approved a remediation plan and work is in progress. Cleanup timelines vary widely — some sites take decades depending on contamination depth, groundwater involvement, and funding availability.

EPA has identified 10 contaminants of concern at this site, including 1,1,1-trichloroethane, 1,1,2-trichloroethane, 1,1-dichloroethane. Contamination has been detected in groundwater, surface water, buildings/structures, soil, solid waste, free-phase napl.

If you live near this site and have health concerns, your state health department can provide site-specific guidance. EPA maintains a community involvement program for most NPL sites, and site documents — including the Record of Decision, five-year reviews, and public health assessments — are typically available through EPA's Superfund site profile.