Cs-137 contamination of the Techa river flood plain near the village of Muslumovo

The results of a radiometric survey of the Techa river flood plain near the village of Muslumovo in the Chelyabinsk region of Russia are presented. Th e observed territory extended 16.6 km along the riverbed, with a total area of 2.5 km(2). The collimated scintillation detector technique was applied to in situ field measurements oF Cs-137 deposition on the soil. Maps of Cs- 137 deposition and soil penetration depth were developed on the basis of ap proximately 5000 measurements. The total Cs-137 deposition within the surve yed territory has been estimated at 6.6 TBq. The means of the total Cs-137 soil depositions at half-kilometer sites on the flood plain and its distrib ution along the river have also been calculated. A maximum Cs-137 contamina tion above 7.5 MBq/m(2) is associated with a bank height up to 1 m above th e usual water level. The data identify zones of intensive radionuclide sedi mentation and transit zones. (C) 2000 Elsevier Science Ltd. All rights rese rved.