Investigations and radiological assessments of mining residues in Germany

Abstract

For centuries, exhaust air and sewage were released from mines and processing facilities into the environment, and mining debris and waste from ore processing were dumped there. The concentrations of naturally occurring radionuclides can be considerably increased compared to soil and surface-near rocks and significantly increased radiation exposures can result for members of the public. In addition, measures of radiological protection have to be considered in many cases. Since the situation has arisen due to operation prior to regulations of radiological protection or operations conducted under inadequate radiological protection control, it is categorized as intervention situation. The principles for justifying intervention measures and for establishing action levels to be applied in remediation programmes for mining residues are discussed. Since the contamination of mining sites results from naturally occurring radionuclides, the natural background exposure should be taken into account in establishing appropriate action levels. Following the principle that radiation exposures being in normally occurring natural range do not require protection measures, the National Commission on Radiological Protection recommended criteria for the justification of remediation measures in case of radioactive contaminations of the environment arising from mining activities. The figures and the conditions of their application are discussed, as well as the practical approaches developed for the radiological assessment of mining residues in the Wismut remediation programme and in the programme for the evaluation of residues due to former mining activities.