Beginning in 1942, the government acquired approximately 218,881 acres in Highlands, Okeechobee and Polk Counties in central Florida to establish Avon Park Army Airfield. After the war ended, the military transferred 112,771.6 acres of land east of the Kissimmee River in Okeechobee County to other entities while maintaining about 106,000 acres west of the Kissimmee River and currently uses it for the Avon Park Air Force Range. The 112,771.6 acres along with a 1.04 acre area along Arbuckle Creek in Highlands County comprises the Formerly Used Defense Site. The Kissimmee Prairie Preserve State Park encompasses a large portion of the former training area.
The Corps finalized a Remedial Investigation in June 2018 to determine what munitions and munitions constituents (the metals and explosives that comprise munitions) may be present in what locations and amounts. Teams investigated almost 5,000 objects, of which only 2 were munitions and considered dangerous. The items with a potential hazard were bomb fuzes located in the sediment in Arbuckle Creek where fuzes were improperly disposed of by being dumped off a bridge. Teams also located munitions debris consisting of pieces from practice munitions and bullet casings; these items do not pose a risk to people or the environment. Samples were also collected from the soil, sediment, and surface water to analyze for munitions constituents. No explosives were detected, and the levels of metals detected pose no risk to people or the environment.
Based on the results of the Remedial Investigation/Feasibility Study, the Corps divided the site into two Munitions Response Sites: Remaining Lands (59,562.28 acres), which includes all the land on the east side of the Kissimmee River, and Arbuckle Creek Fuze Disposal Area (1.04 acres). There is a potential risk from people encountering bomb fuzes within the Arbuckle Creek Fuze Disposal Area, and an acceptable risk in Remaining Lands.