Citat fra kapitel 7.4.4 ang. Kvanefjeldsprojekt side 58: A very critical point for environmental hazards in this project is the tailings management. According to current considerations GMEL favour tailings disposal in the nearby natural lake Taseq (GMEL 2009). Following an extensive study Risø (1990) concluded that the outlet from contaminated water from Taseq would cause pollution of the whole fluvial system (from the lake, via rivers, into the ocean) with radioactive substances, fluorine and heavy metals. It is very doubtful if waste water treatment installations at the outlet of the lake are capable to manage the large amounts of water particularly in times of heavy rain or snow melting. The extensive work on the Kvanefjeld deposit (the results of which were published by Risø in 1990) was conducted by Danish authorities and scientists up to the early 1980s and also form the basis of the GMEL planning activities (GMEL 2010c). This work was carried out with the focus of mining uranium only and provides very detailed considerations and analysis Study on Rare Earths and Their Recycling 59 results concerning environmental impacts. Beside the tailings impoundment it identified the open pit and the waste dump as the most important sources of pollution. In the long term (> 100 years) the tailings pond will be the most critical point. Risø (1990) compared two options: the direct inlet of the tailings into the sea and the tailings disposal in the nearby natural lake Taseq (see above). The latter was considered even worse in terms of environmental impacts than the direct inlet into the ocean. Though waste disposal in oceans was frequently practised in the past, the procedure is not acceptable at all either. Equally, inlet of toxic tailings into natural water bodies has to be banned completely and does not meet any environmental standards. The situation in Greenland seems particularly critical when considering the fact that the expected climate change – it is linked to melting of glaciers and unfreezing of permafrost soils – might alter water bodies and the stability of soils considerably. The next paragraph gives a short overview of the planned technologies for the GMEL-Kvanefjeld project and the progress of the (pre-)feasibility studies and approval issues: Mining shall be carried out in a conventional open pit followed by uranium extraction with the Carbonate Pressure Leach- (CPL-) technology. The CPL-residue can then be processed and the REO concentrated by froth flotation, leached with acid and then refined to produce rare-earth-carbonate. The nominal forecast annual production amounts to approx. 44 000 t REO and nearly 4 000 t of uranium oxide; the overall plant recovery rates are 34 % and 84 %, respectively (GMEL 2009).
Posted on: Sat, 03 Jan 2015 13:10:26 +0000
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