WWII-era munitions found submerged

LOS ANGELES — Underwater dump sites off the Los Angeles coast contain World War II-era munitions including antisubmarine weapons and smoke devices, marine researchers announced Friday.

A survey of the known offshore sites in April managed to identify munitions by using high-definition video that covered a limited portion of the sites, the Scripps Institution of Oceanography at the University of California, San Diego, which led the survey, said in an email.

The survey, which used deep-water uncrewed vehicles equipped with sonar and a video camera, was a high-tech follow up in a region known to have been the dumping ground for industrial and chemical waste from the 1930s through the 1970s.

A 2021 survey using sonar had uncovered more than 25,000 “barrel-like objects” on the sea floor that possibly contained DDT and other toxic chemicals. High levels of the toxic chemical were previously found in sediments and marine mammals in the region, and DDT has been linked to cancer in sea lions.

However later research, including from the U.S. Environmental Protection Agency, suggested that much of the contamination may have come from acid waste containing DDT that was stored in above-ground tanks and then dumped into the sea in bulk from barges rather than in barrels.

The April survey included taking some 300 hours of highdefinition video in a slice of that area, which allowed researchers to identify some of the mysterious boxes and barrels thousands of feet below the surface on the sea floor in lines between the mainland and Santa Catalina Island, Scripps said.

“In every debris line sampled with video, the majority of targets were found to be munitions,” the Scripps email said. “According to scientist Eric Terrill: ‘we started to find the same objects by the dozens, if not hundreds.”’