What Margo Edwards calls “My Scientific Detective Story” begins with flashbacks.
World War II is over. Mustard agent (a liquid used to produce mustard gas) has been stockpiled for decades from Europe to Asia. Disposal options: bury, burn or dump the containers at sea.
Years later, Baltic Sea fishermen find unusual nodules in their nets. The polymerized balls contain liquid that burns the skin of people who come in contact with it.
The United States signs a 1975 treaty banning ocean disposal of chemical weapons. One year later, scientists conducting a biological survey for the Department of Defense south of Pearl Harbor find a dozen leaky cylinders; people handling them suffer mustard burns. A follow-up survey observes conventional munitions, but no additional mustard containers.
Fast forward to 2007 and federal legislation requiring the military to identify its disposal sites. Hawaiʻi Institute of Geophysics and Planetology Researcher Roy Wilkens proposes that the University of Hawaiʻi’s School of Ocean and Earth Science and Technology employ its expertise.
The resulting Hawaiʻi Undersea Military Munitions Assessment, or HUMMA, is the first study of possible chemical weapons sites in Hawaiʻi and the most comprehensive study ever taken in U.S. waters, says Edwards, the HIGP researcher who headed the project.
Under a $2.8-million contract with the Army, the UH team searched for a chemical needle in a 500-meter-deep haystack outside Pearl Harbor. To improve their odds, they scrutinized historical photos and memos provided by the Army and queried witnesses.
Honolulu resident Tom Clarke, who had worked on the barges, used traditional Hawaiian navigation techniques to identify where objects were rolled overboard.
The team also viewed video from the Hawaiʻi Undersea Research Laboratory’s frequent training dives in the area, which had documented munitions along with World War II Japanese submarines. (See Mālamalama reports on a Japanese minisub and pair of Japanese attack subs).
The Hawaiʻi Mapping Research Group then spent five days crisscrossing the area, collecting sonar data that revealed what looked like beaded ant trails. Submersibles went in for a close-up view.
“We found ammo boxes, lots of steel cable, depth charges,” along with a lot of civilian trash from tires to stuffed toys, says Edwards. Munitions were largely intact, but none were identified as the chemical culprits.
Still, she counts the investigation a success.
“A secondary goal of HUMMA was to develop a systematic approach for locating, bounding and characterizing deep water sea disposal sites,” she explains. “This approach will serve as a template for developing cost-efficient methodologies for use at other sites of similar or deeper depths.”
The munitions that were found were mapped. Water, sediment and sea life samples taken near them are being analyzed.
“We wanted to look at the ocean’s effect on munitions and munitions’ effect on the ocean,” Edwards says.
While the Pearl Harbor site had few species consumed by humans, lessening the risk from bioaccumulation of toxins here, munitions and mustard agents were also dumped near fishing areas such as the Northeast Atlantic and off the Gulf Coast, she points out.
“My children still get to swim at Magic Island,” says Edwards. Still, with 16,000 deteriorating containers out there, she urges additional surveys and continued monitoring. And she reminds students who are aghast at the military dumping that their generation is hardly blame-free.
The debris littering the seafloor not far from one of the island’s most beautiful beaches contains “more Bud cans than bombs,” she says…and the beer cans look new.
Read more about Arctic adventures of the Hawaiʻi Mapping Research Group in Mālamalama.