The Longhorn Army Ammunition Plant (LOW) was a 8,493-acre (34.37 km2) government-owned, contractor-operated (GOCO) facility in Karnack, Texas that was established in 1942.
The Monsanto Chemical Company selected the site in December 1941 to produce TNT.
[5] The United States Environmental Protection Agency listed the primary contaminants of concern as solvents used at the site.
The groundwater, surface water, and soil on the plant have been found to be contaminated with perchlorate.
Sediment samples from streams near Caddo Lake found elevated levels of lead and mercury.