Possibilities for the rehabilitation of settlements affected by large scale radioactive contamination

¹ Risoe National Laboratory, P.O. Box 49, 4000 Roskilde, Denmark
² KFKI Atomic Energy Research Institute, P.O. Box 49, 1525 Budapest, Hungary
³ Polessye Enterprise, 11 Karpovicha Str., 246017 Gomel, Belarus

Abstract

With the support of the IAEA, a decontamination exercise was conducted in the highly contaminated area of Masany, Belarus. The aim of the work was to determine the effectiveness of decontamination methods. On the roof two different methods were used: a special roof-cleaning trolley, that can safely decontaminate asbestos type roofs, and a high pressure hot water jet, using either clean water or water with a detergent added. The decontamination factors, DF's were of the order of 0,2-0,3 for both methods. The walls were decontaminated by high-pressure hot water jet, planing of wooden walls, and industrial vacuum cleaning resulting in DF's 0,1-0,5. The upper layer of the surrounding soil areas was removed to a depth of about 10-cm, giving dose rate reduction factors, DRF's of 0,1-0,3. Inside the house, vacuum cleaning was performed with very little effect. In the kitchen garden three different methods were used: removal of the upper 10-cm soil layer (DRF of 0,25), triple digging (DRF of 0,3), and normal digging (DRF of 0,5). In conclusion, it was demonstrated that it is still possible, more than a decade after the Chernobyl accident, to substantially reduce the external dose rate in and outside a dwelling by forced clean up.