MOSCOW, October 23. /TASS/. The expedition on the Akademik Mstislav Keldysh vessel in September and October studied the submerged K-27 nuclear submarine and nuclear waste burials in the Kara and Barents Seas and did not find radioactivity releases, press service of the Shirshov Institute of Oceanology (the Russian Academy of Sciences) said.

"During the expedition, organized by the Kurchatov Institute National Research Center and the Institute of Oceanology, scientists studied nuclear waste burials in the Kara and Barents Seas, conducted oceanology observations and analyzed geomorphological features of the bottom relief in the Norwegian, North and Baltic Seas. The expedition did not reveal obvious releases of radioactivity from the sunken objects. The found level did not exceed the equipment's detection limits and was ten times less than the natural background," the press service said.

The expedition participants updated coordinates of potentially dangerous objects in the Kara Sea, assessed their conditions, and tested water and sediments for radiation safety. Underwater video filming of the K-27 nuclear submarine's hull was performed in Stepovoy Bay to make a 3D model of the boat, which will be used to create a permanent radiation monitoring underwater station. It was for the first time that scientists performed geophysical sounding of the bottom adjacent to the K-27 and to the shore, where the station's onshore unit will be installed.

The scientists performed a continuous sonar survey of the Depression-South solid radioactive waste burial site, which occupies more than 200 square kilometers, investigated the site where the Likhter-4 vessel was sunken in the Gulf of Currents near Novaya Zemlya, which had been exposed to icebergs and hummocks for 36 years.

"At the final stage of work in the Barents Sea, a sonar survey was carried out to confirm archival data on the sunken Nickel-type barge with a cargo of solid radioactive waste and to study radioactive background near that site. However, the submerged vessel was not found in the location indicated in the archival sources. The radioactive background has not been exceeded," the institute said.

At the end of the expedition, scientists studied relief of the Arctic basin bottom: they measured depths on the shelf of the Barents Sea, the Norwegian and North Seas, and also carried out measurements in the Baltic Sea. High-frequency sounding of the shelf sedimentary cover's upper layer was carried out throughout the routes. Using the research results, the scientists made profiles of the seabed depths and structures of the bottom sedimentary deposits' upper water-saturated layer.