CONCEPTION AND METHODOLOGY OF A PROSPECTIVE SAFETY REPORT FOR URANIUM MILL TAILING PONDS: EXAMPLE „TAILING POND LENGENFELD”, SAXONY

Key words: abandoned waste disposal sites, arsenic, case study, exposure path- way, geochemical transport modelling, groundwater, in-situ remediation, mine tailings, radioactive contamination, risk assessment, uranium wastes

Tailing ponds stand for the highest potential risk of all legacies from the ura- nium mining and milling industry. Taking into consideration their large vol- umes, one should principally rely on an on-site remediation of such objects. Due to the specific features of the tailings and especially to the fact that the older plants had been created without intention of the long-term stability, the radiological, chemical-toxic and geomechanical impacts and risks must be ana- lysed. On this basis the best suited remediation option must be determined. To analyse the success of countermeasures and, if necessary, to conduct any re- spective follow-up measures, it is indispensable to carry out a long-term and continuous safety assessment based on the safety relevant data and information from monitoring. This would enable the authorities and the operator for a prompt and fit-for-purpose response.