Oil exploration raises issue of undersea munitions, including Tybee bomb

Savannah Morning News
April 30, 2018

By Mary Landers

Frank Knapp has been battling the prospect of offshore drilling for years, convinced the industry’s infrastructure or a major spill would spoil the lucrative tourism and commercial fishing industries in the Southeast.


Lately, though, he’s sounding a new alarm that focuses not on oiled beaches or injured dolphins but on the huge quantities of undersea munitions dumped off the East Coast following WWI and WWII. And off the Georgia coast, he points out, there’s the additional question of the never-located “Tybee bomb,” a nuclear weapon lost during a training exercise 60 years ago.

“Government documents and first-hand accounts of munitions and radioactive waste being dumped off the Atlantic Coast from Massachusetts to Florida came to our attention only recently,” Knapp, president and CEO of the S.C. Small Business Chamber of Commerce, wrote in recent comments to federal regulators. “Nine of the official dump sites are off the South Carolina coast. There is a serious threat of seismic airgun blasting disturbing these materials, many in unofficial and unknown locations and all in deteriorated containers, and releasing them into the water. Commercial fishing, the public, local economies and even seismic ships and crews are in jeopardy.”

Seismic testing uses repeated loud blasts of compressed air to map the sea floor. The Bureau of Ocean Energy Management has proposed mitigation to protect sea life from the effects of the barrage of underwater noise, but concerns persist that the air guns will harm sea life ranging from plankton to whales. The issue of its effects on undersea ordinance, however, is a new one.

Seismic testing is a precursor to drilling, but it’s regulated separately. There are currently eight seismic permits under review for the Atlantic offshore area that includes Georgia and the Bureau of Ocean Energy Management is expected to render its decision on them soon. Earlier this year the Trump Administration announced plans to consider almost all of the U.S. coast for exploration and drilling. The new draft plan proposes three lease sales in the South Atlantic planning area that includes Georgia. It also removed the 50-mile buffer included in the previous plan.

The National Ocean Industries Association, a trade group, rejects the idea that seismic testing could affect undersea weapons dumps.

“Assertions by the South Carolina Small Business Chamber of Commerce and local mayors claiming proposed Atlantic seismic surveys pose a risk of triggering the release of toxic chemical and radioactive waste are patently false,” wrote Nicolette Nye, vice president of communications & industry affairs and a retired Navy officer. “This issue has never been a concern anywhere in the world. Seismic surveys have been conducted around the world for eight decades and extensively for the last five decades with no scientific documentation of any sound impacts causing the initiation of explosions or the compromise of storage containers containing chemical or radioactive waste.”

Munitions dumps and Tybee bomb

Nobody disputes that there’s a lot of munitions out there.

The Department of Defense disposed of excess, obsolete, serviceable, and captured enemy munitions in the waters off the shores of the United States until 1970, initially in waters as shallow as 300 feet. At the time, sea disposal was considered one of the safest alternatives available to dispose of munitions. A 2009 Department of Defense report indicated the DoD disposed of approximately 32,000 tons of chemical agents in waters off the U.S. coasts. The agents disposed of included lewisite, mustard and arsenic trichloride. More than half the total was dumped off the Atlantic coast.

Maps included in that report show dumps off South Carolina and some farther offshore of the South Carolina/Georgia border. They don’t include the Tybee bomb, which was not a planned disposal. Instead, an accident during a training mission in February 1958 forced a Navy pilot to jettison into Wassaw Sound the nuclear weapon his B-47 was carrying. That pilot, retired Air Force Col. Howard Richardson, told the Savannah Morning News in 2008 that the bomb was not armed with its removable plutonium trigger. The Pentagon concurred. But the 7,600-pound weapon did contain 400 pounds of conventional explosives and highly enriched uranium. Despite a nine-week search at the time and another effort in the early 2000′s the bomb was never recovered.

The DoD’s Environment, Safety and Occupational Health Network and Safety Exchange, or DENIX, warns that “munitions are dangerous and can explode if approached, touched, moved or disturbed.” And a 2016 DoD report to Congress concludes that it’s best to leave undersea munitions where they are.

“From an explosives safety perspective, DoD believes that it is best to leave sea-disposed munitions in place. DoD has found that the recovery of these munitions would likely result in a rapid release of munitions constituents that could cause more harm than would otherwise occur as the munitions continue to deteriorate over time,” the report states.

The DENIX program did not respond to a request for comment.

For Knapp, DoD’s own advice applies to the use of seismic testing offshore.

“We agree with the military,” Knapp said. “The military concluded in the report in 2016 to leave all the munitions and chemical weapons alone. We agree with that. They say you shouldn’t try to mitigate it or try to recover it. We agree because their concern is it’s going to disturb that material and set it free in the environment. We believe that the seismic airgun blasting has a possibility of disturbing that material. We agree with the military. Leave it alone.”

Risks of seismic

Seismic surveys have encountered munitions in the past, said Margo Edwards, a geophysicist and director of the Applied Research Laboratory at the University of Hawaii.

“In Europe in the Baltic Sea where they were siting wind farms and pipelines they did encounter munitions,” she said. “In those cases nothing happened.”

Edwards is among the researchers whose work is cited in the 2016 DoD study. She maps munitions and tests nearby sediments and animals for contamination near Hawaii where the deep, warm water is especially conducive to corrosion. Her team’s robotic vehicles come into contact with munitions while collecting samples without incident. Seismic surveying doesn’t seem like a big detonation threat to her.

“Detonation is probably highly unlikely,” she said. “I can’t say 100 percent it would never happen.”

At the University of Georgia, James W. Porter, Meigs professor of ecology, emeritus, is less sanguine. He’s concerned about both the threat of detonation and the threat of contamination as the munitions corrode. His experience working on coral reefs in Puerto Rico suggests there are more undersea munitions at more places than the DoD has tracked.

“I had been told by the DoD that there was no unexploded ordinance at Vieques,” he said. “I didn’t want to go diving with bombs. That was not my idea. Less than a minute over the boat we encountered large unexploded bombs.”

He’s not suggesting that seismic surveys could trigger the Tybee bomb; even if it were armed the detonation for nuclear devices is a complicated mechanism, he said. Nor does he think seismic surveys would speed up the deterioration of the metal casing, though sea water could do that on its own over time, releasing radioactive material into the water, he said.

With seismic, he’s most concerned about unleashing the carcinogens contained in unexploded ordinance.

“If a seismic blast occurs near unexploded ordinance it can explode that ordinance,” he said. “Caution needs to be taken in choosing the sites for testing.”

His work in Puerto Rico documented eight carcinogens, including benzenes and toluenes, in the water sediment and animals tested some in high concentrations. The data showed that toxic substances leaking from unexploded ordinance enter the marine food web and are passed up the food chain, he said. Health data for long-term residents of Vieques show significantly elevated levels of cancer and several other types of chronic illnesses (hypertension, asthma, epilepsy and cirrhosis). The types of cancers and the timing of their appearance are all consistent with a causal relationship between the carcinogenic compounds released on the island during military exercises and the expressions of cancer among the island’s residents. But cancer clusters are notoriously difficult to pin down and the federal government rejected these findings, saying the sampling was flawed, Porter said.

Like the federal government, the industry points to the lack of evidence of a link. Seismic surveys have been going on for decades on the Atlantic Outer Continental Shelf including recent surveys since 2014 off North Carolina, New York, New Jersey and Massachusetts to site wind farms, and record sea level rise.

“It is important to note that during this now four-year duration, there have been no reports of seismic survey activity triggering the release of toxic chemical agents or radioactive waste from official and unofficial ocean dump sites in the U.S. Atlantic,” wrote NOIA spokeswoman Nicolette Nye. “This latest false claim against seismic surveys in the Atlantic appears to be yet another case of fear mongering by groups and officials opposed to oil and gas exploration and development.”


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