Radiological assessment of residues from uranium and other ore mining and processing - A precondition for decisions on remedial measures

In certain parts of Eastern Germany relics of uranium mining and milling as well as of traditional ore mining and processing may contribute to the environmental contamination and the radiation exposure of the public. Systematic investigations of the situation are the indispensable prerequisite for decisions upon the radiological relevance and remedial actions. In view of the large number and scattering of relics under consideration, a stepwise procedure with increasing intensity of investigation was developed to solve the task effectively and in an appropriate time. For the radiological evaluation following the steps of investigation generic criteria were derived. They are based on a primary reference dose of level (1 mSv/year) and on measureable radioactivity quantities recommend by the German Commission on Radiological Protection for unrestricted/restricted release of contaminated grounds. Applying the criteria established for the verification (gamma dose rate, volume of disposed material, area affected by waste materials) the investigations led to the result that no more than 30% of the objects of former mining have to be classified as open-quotes possibly relevantclose quotes and have to be investigated further on