Horn Island was under the jurisdiction of the Department of Interior, and in 1947 an Officer from the U.S. Army Technical Services Unit requested a clearance permitting work on Horn Island. From July 21 to August 1, 1947, approximately 40 250-kilogram and 90 500-kilogram German mustard-filled, leaking bombs were destroyed by burning. The bombs were placed in a shallow trench with dry wood, pine cones, oil-soaked rags, and fuel oil. The bombs were ruptured with rifle fire and ignited. Upon completion of the burning, the area was inspected to determine if all the bombs had ruptured and burned and to test for agent contamination. The empty bomb casings were loaded onto a barge and dumped at sea. The equipment and area used on Horn Island also were decontaminated.

This island was used by the U.S. Chemical Warfare Service (CWS) as an experiment station beginning in 1943. The island was also used in 1946 to destroy approximately 130 captured German mustard gas bombs from World War II. The Army relinquished all control of the island by December 1948.

Area 27 - On July 27 through 31, 1946, forty 250-kilogram and ninety 500-kilogram bombs from Theodore Naval Ammunition Magazine were burned in shallow trenches and in stacks. 500-kilogram bombs marked by two red bands. Empty bomb casings dumped at sea. First burn on Horn Island in 1946. Air tested during burn for mustard vapor and arsenic had negative results. An Archives Search Report was completed in 1993. The areas where the mustard bombs were destroyed in 1946 has been eroded into the Gulf of Mexico.

An unknown area used for the disposal of German toxic bombs.

Danger Area - A 3 square mile area - Established a danger area for testing new secret warfare agent.