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Abstract.A new assessment of the nuclear dumping sites of Novaya Zemlya was performed in 2003/4. 137 Cs contamination levels within both Stepovogo and Abrosimova Bays are similar to background environmental levels and there has been no detectable leakage from objects in Tsivolki Bay. Near-surface sediment 137 Cs contamination levels in 2003/04 are 1-11 Bq/kg, 4-268 Bq/kg, and 13-20 Bq/kg in Tsivolki, Stepovogo and Abrosimova Bays respectively. These conclusions are further supported by the data for 238 Pu and 239+240 Pu. Hence, leakages from the low-level waste containers on the seafloor have diminished appreciably after ten years while sediment reworking (e.g. mixing, burial, resuspension and transport) and radioactive decay has reduced to negligible the elevated radionuclide levels previously detected in surface sediments. Furthermore, there is no indication that nuclear fuel from the dumped reactors or submarine has been or is presently releasing detectable quantities of radioactivity into the marine environment.

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