MIDI-PYRENEES -- shut downPurpose: extraction and treatment of uranium ore Type: mine and pre-treatment installation Location: Bertholène (Aveyron), east of Rodez Operator: Société des mines de Jouac, subsidiary of Cogéma 100%, formerly TCM and Scumra Period of exploitation: 1981-1994 Raw materials: uranium ore Actual production: mine 65 t/yr in 93/94; leaching 40 t/yr MINE The underground mining took place between 1981 and 1992; the exploitation on the surface between 1981 and 1994 [InfoU iii-iv.92]. The site produced 800 t of uranium in all. The production in 93/94 was 65 t/yr [InfoU vii-viii.94]. The ore contained on average 0.15% uranium. According to Andra, part of the production was sent directly to the plants of Simo at Bessines (Haute-Vienne) and Scumra at St-Pierre (Cantal). Part was pre-treated on the site. PRE-TREATMENT INSTALLATION The installation was used from 1985 to 1994. The ore was treated by leaching in stalls on the surface of the mine. The uranium, trapped in containers of resin, was transported to reprocessing plants in Jouac (Haute-Vienne) and Saint-Pierre (Cantal) [Andra 1999]. Production amounted to 40 t/yr of uranium metal contained in the concentrates [Bugarel 86]. The installation treated 475,915 t in total [Andra 99]. SOLID WASTES The site stocks 475,915 dry tons of tails containing 613 t of uranium. The activity of the 475,915 t is 7.57 TBq in radium 226. The tailings are in a basin in the valley of Balaures (the brook has been turned aside), behind a dike that was only a pile of waste rock and waste from the mine but is now being “reshaped.” The tailings are covered with waste rock. LIQUID EFFLUENTS The liquid residues from the containers, were treated-the radium made insoluble and neutralized -and then poured onto the tailings dump [InfoU iii-iv.92]. “The bottom [of the basin] and of the dike not having been made tight, the main problem [at the site as of 1993 was] that of the contamination of underground water” [InfoU i.ii.93]. “Water is treated before release” [Andra 99]. |