[Inventory and systematization of data on radiation-chemical contamination of rivers running along Bryansk-Belarusian "cesium spot"]

10). At present for estimation of radiooative contamination of surface water only comparison with republican permissible levels are used. But it is not enough for complex estimation of water quality because it does not enable to estimate the extent of radionuclide exceeding over their permissible levels. Application of RCI enable to compare radioactive contamination before and after the Chernobyl accident. Application of the index of integrated radiation-chemical surface waters contamination enable to obtain the most complete and impartial estimate of surface water quality of some rivers. Retrospective estimation of the water quality shows that in 1990 surface waters of some rivers shoud be considered as belonging to more contaminated category of quality if radiation component would have been considered" WRAPInventory and systematization of the data on radioactive-chemical contamination of rivers are made. Systematization of the data on chemical and radiation contaminaton component of rivers was made with using the index of integrated radiation-chemical surface waters contamination (IRCCI=WCI+RCI). Chemical contamination of surface water has been estimated using water contamination index (WCI). It constitutes an integrated magnitude considering rations of six more significant pollutants to their maximum concentration limits. In dependence on WCI surface water can be attributed to one of seven classes: from "clean" (with WCI 1) to "extremely dirty" (with WCI 10). At present for estimation of radiooative contamination of surface water only comparison with republican permissible levels are used. But it is not enough for complex estimation of water quality because it does not enable to estimate the extent of radionuclide exceeding over their permissible levels. Application of RCI enable to compare radioactive contamination before and after the Chernobyl accident. Application of the index of integrated radiation-chemical surface waters contamination enable to obtain the most complete and impartial estimate of surface water quality of some rivers. Retrospective estimation of the water quality shows that in 1990 surface waters of some rivers shoud be considered as belonging to more contaminated category of quality if radiation component would have been considered