Soviet nuclear sub that sank off Norway in 1989 still emitting radiation

Komsomolets in 1986 Image: US Department of Defense Komsomolets in 1986

Researchers have confirmed that a Soviet Navy nuclear-powered submarine lying at the bottom of the sea after it sank off southwestern Norway 30 years ago is still releasing radiation.

According to a July 10 statement by the Norwegian Radiation and Nuclear Safety Authority (Direktoratet for strålevern og atomsikkerhet; DSA), a number of seawater samples taken near a ventilation pipe on the sunken Project 685 submarine Komsomolets revealed a level of radioactive caesium that is far higher than levels normally found in the Norwegian Sea.

The highest level which has been measured in these seawater samples was 800,000 times higher than normal, the DSA added.

The agency has assured the public that, despite the elevated readings, the radiation releases posed no threat to people or the marine environment.

Komsomolets sank on April 7, 1989, with the captain and 41 others among the submarine's 69 crewmembers perishing, after a fire broke out on board.

Seawater samples were specifically collected from the ventilation pipe as previous Russian expeditions to the submarine in the 1990s and in 2007 had documented radiation releases from the reactor through this part of the vessel.

The highest level researchers found was around 800 Bq per litre whereas present-day typical levels for seawater in the Norwegian Sea are around 0.001 Bq per litre.

Sign up to the FREE Work Boat World newsletter