KOROR, Palau — More than 82 tons of unexploded World War II bombs have been removed from a sunken ship in Malakal Harbor, ending a seven-year operation of the Japan Mine Action Service (JMAS).
The ship, known as the Helmet Wreck, was a Japanese merchant vessel converted for wartime use during WWII. It was sunk with 469 depth charges aboard and lay undisturbed on the ocean floor for 81 years before the dangerous cargo was finally cleared.
JMAS, working alongside the Palau government, Koror State, and Norwegian People’s Aid (NPA), removed the deteriorating depth charges—each weighing about 160 kilograms (352 pounds) and measuring roughly 2.5 feet long and 17 inches in diameter. The charges, which contain ammonium picrate, a highly toxic explosive compound, were leaking hazardous chemicals into the surrounding waters.
“Visitors, especially divers, may not be happy because this was a popular dive site, but I believe the removal was necessary for the safety of everyone, including marine life,” said Shimada Masato, a JMAS representative. He explained that many of the bomb casings were cracked, with orange-yellow toxic liquid seeping out.
The removal was a painstaking process. Each bomb had to be sealed to prevent leaks, bagged individually, brought to the surface, and transported overland to a demolition site in Babeldaob. There, NPA incinerated the bombs.
Despite the complexity and risks, Shimada said the project was completed safely without accidents. He credited the Japanese government’s support and funding for enabling the operation, which aimed to eliminate the threat posed by WWII-era ordnance in Palau’s waters.
JMAS, a Japanese non-governmental organization specializing in demining and unexploded ordnance removal worldwide, led the effort.