A clam dredger's surprise catch of 10 rounds of munitions filled with mustard gas is a reminder that oil isn't the only hazard humans have unleashed in the sea.
The 145-foot ESS Pursuit, a commercial fishing vessel based in Atlantic City, N.J., dredged up the military shells June 6 in 60 feet of water over a charted munitions dump near Hudson Canyon, 45 miles south of Long Island, N.Y. Fishing is not prohibited over discarded munitions, though in a study of Vieques, a Puerto Rican island long used as a Navy bombing range, scientists found unsafe levels of carcinogens from shells in the water in nearby sea life.
The Coast Guard identified the haul of mustard gas shells as World War I rounds. One of them broke open while the crew brought it aboard with a load of clams, exposing four men to mustard gas and causing chemical burns (blisters) and breathing problems, the Coast Guard reports.
The crew threw the lethal shells overboard, but on arrival in New Bedford, Mass., ESS Pursuit was quarantined at a mooring while Massachusetts National Guardsmen and a Navy team trained in ordnance disposal decontaminated the vessel. Four of the vessel's six crewmembers were treated at a hospital for exposure to mustard gas. The catch - 6,000 bushels of quahogs worth $50,000 - was shipped to a hazardous waste incinerator and burned.
Mustard gas, also known as sulfur mustard, is a chemical weapon developed during World War I. It was delivered in liquid or gas form and caused blistering of the skin, eye irritation that could lead to blindness, and severe lung injury if inhaled.
Until 1970, it was not uncommon for the United States to dispose of "excess, obsolete and unserviceable munitions en route to port or as part of planned disposals," says an Army pamphlet on what to do with unexploded ordnance discovered at sea.
"Bombs, rockets, projectiles, small arms, biological, chemical and radiological wastes - everything" is how Jim Barton, 55, of Norfolk, Va., describes the U.S. military ordnance lying on the sea floor. "All up and down the Eastern Seaboard the waters are littered with dumps and live-fire training ranges." The same is true of the Great Lakes, Gulf of Mexico, Pacific Coast, Chesapeake Bay, and the waters off Alaska and Hawaii, says Barton, who owns the Norfolk-based Underwater Ordnance Recovery.
Barton, a retired Navy bomb disposal diver for 23 years who headed up the Vieques study for the attorney general of Puerto Rico, says more than 1 million tons of cast-off munitions lie on the bottom of the Great Lakes alone. "The Great Lakes are dumping grounds for huge, huge quantities of munitions," he says, and have been used often for live-fire exercises. "They've never been cleaned up."
The Coast Guard is advising fishermen to steer clear of charted "explosives dumping areas" in light of the recent mustard gas accident. Barton, who is writing a book on munitions disposal and has built a prototype of a seafloor-based robot for recovering ordnance, says his research suggests that less than a third of U.S. undersea dumps are identified, let alone charted.
He says most dumped munitions are disarmed and unlikely to explode but that you can't know for sure, so every shell must be considered live. Whether they can explode or not, the shells and their contents are an environmental hazard and a potential health threat. "We haven't even begun to address munitions in the water, and I'm not sure we ever will," he says.
Barton's robot rides on the seafloor on rubber tracks and carries a 15-foot boom for recovering bombs up to 2,000 pounds at depths to 250 feet. He wants to use his robot to clean up hazardous military waste, but he says there's no national policy to do that. "We have a policy of abandoning defense waste found in the marine environment," he says. "It's tragic."
Information on handling munitions found at sea is available at aec.army.mil, search keyword "mmrp-maritime."
This article originally appeared in the August 2010 issue.