U.S. Disposal of Chemical Weapons in the Ocean: Background and Issues for Congress [Updated October 23, 2006] [open pdf - 113KB]
"The U.S. Armed Forces disposed of chemical weapons in the ocean from World War I through 1970. At that time, it was thought that the vastness of ocean waters would absorb chemical agents that may leak from these weapons. However, public concerns about human health and environmental risks, and the economic effects of potential damage to marine resources, led to a statutory prohibition on the disposal of chemical weapons in the ocean in 1972. For many years, there was little attention to weapons that had been dumped offshore prior to this prohibition. However, the U.S. Army completed a report in 2001 indicating that the past disposal of chemical weapons in the ocean had been more common and widespread geographically than previously acknowledged. The Army cataloged 74 instances of disposal through 1970, including 32 instances off U.S. shores and 42 instances off foreign shores. The disclosure of these records has renewed public concern about lingering risks from chemical weapons still in the ocean today. In the event that the weapons are located, retrieving them from the seabed could be technically challenging and could introduce new risks during retrieval and transport for onshore disposal. Leaving located weapons in place, and warning the public to avoid these areas, may be more feasible and involve fewer immediate risks. However, long-term risks would remain. Responding to potential risks is further complicated by insufficient information to reliably estimate response costs and by the uncertain availability of federal funding to pay for such actions."
CRS Report for Congress, RL33432