Key Facts
- Program duration
- 1964 – early 1970s
- Minimum offshore distance
- 250 miles (400 km)
- Chemical weapon sinkings
- 4 out of total sinkings
- Chemical disposal site
- Atlantic Ocean, between Florida coast and the Bahamas
- Preceding disposal (1958)
- 8,000 short tons of mustard and lewisite gas aboard SS William C. Ralston
- Typical sinking time
- ~3 hours after seacocks opened
Strategic Narrative Overview
Under the program, surplus munitions were loaded onto ships, primarily Liberty ships, which were then sailed at least 250 miles offshore before Explosive Ordnance Disposal teams opened the seacocks. The vessels typically sank within three hours. Most operations involved conventional weapons disposed of across Atlantic and Pacific Ocean sites, but four dedicated operations targeted chemical weapons, with those sinkings concentrated in a three-mile area of the Atlantic between Florida and the Bahamas.
01 / The Origins
After World War II and subsequent conflicts, the U.S. military accumulated large stockpiles of unwanted conventional and chemical munitions. By the early 1960s, the Department of Defense required a systematic disposal method. Ocean dumping was seen as a practical and contained solution, leading to the creation of Operation CHASE in May 1964, formalized under the acronym 'Cut Holes And Sink 'Em,' to manage the growing surplus of hazardous weaponry.
03 / The Outcome
Operation CHASE concluded in the early 1970s amid growing environmental and public concern over ocean dumping of hazardous materials. The program was eventually discontinued, and subsequent U.S. policy shifted toward land-based destruction methods for chemical weapons. The sunken munitions, particularly the chemical weapon caches, remained a subject of ongoing environmental monitoring and concern regarding long-term ocean contamination risks.
Belligerents & Mobilization Analysis
Side A
1 belligerent