Clean-up of legacy waste is continuing at the radiochemical plant of Russia's Siberian Chemical Combine (SCC). The second stage of care and maintenance began on 6 May at reservoir B-1, which was used to store liquid radioactive waste. The first stage, completed in late 2015 as part of the Federal Target Programme (FTP) "Nuclear and Radiation Safety in 2008 and until 2015" (FTP NRS-1), involved covering the reservoir area and localising radionuclides which had accumulated in the sludge and bottom sediments.
The second stage will take three years and is being implemented under FTP NRS-2 (for 2016-2020 and until 2030). This stage will include backfilling the reservoir layer-by-layer. A drainage layer of crushed stone will prevent substances rising through capillary action from the bottom and a shielding layer of clay will protect the storage facility from the atmosphere.
This radwaste isolation technology was previously tested and applied in decommissioning a similar facility at SCC - reservoir B-2. AA radiation safety monitoring system will be put in place around the mothballed facility and a draining system will be built around the reservoir to collect flood water and atmospheric precipitation. The mothballed facility will be submitted for approval to the state commission in 2018.