The Corps conducted a Remedial Investigation/Feasibility Study on portions of the former Passage Key Air-to-Ground Gunnery Range designed to identify target locations and to determine if anything remains in the area from the military's training, and if so, in what amounts and locations. The crews found expended ammunition and pieces from munitions; these types of items are referred to as munitions debris, and they do not pose an explosive hazard. The teams also identified munitions in the water which included two bomb fuzes, a rocket and a 37 millimeter projectile. No munitions were found on land.
During World War II, air crews assigned to the Sarasota Army Airfield used Passage Key for a strafing and skip bombing range. There were two banks of targets facing north and south about 500 feet apart, and each bank had six targets. Crews trained with machine guns and practice, and, possibly, live bombs. The targets are now completely under water.
The Passage Key Air-to-Ground Gunnery Range Formerly Used Defense Site in Manatee County comprises 13,147 acres, most of which is the water around Passage Key in Tampa Bay. The US Fish and Wildlife Service owns the island and manages it as the Passage Key National Wildlife Refuge. It is not open to the public.