Water balance and pumping requirement – Northern Luossajärvi
The expansion of LKAB’s mine in Kiruna affects the water balance in the surrounding lake system.
LKAB’s mine in Kiruna is being expanded and there is a risk that lakes will be drained. As a consequence of this, part of Northern Luossajärvi has to be drained and the rest of the lake system diverted.
On behalf of LKAB, ÅF has investigated how much water should ideally be pumped to the Luossajoki system (the current regulation system) in order to avoid negative consequences.
Our assignment included the production of a water balance for the Luossajärvi and Lombolo lakes, and the clarification of stored water volumes, i.e. volumes available for pumping from Luossajärvi. We then investigated optimal pump flows at different times of the year with regard to the environment, technology and finance. Fieldwork was carried out in order to investigate the water conditions in the areas with polluted sediment in downstream watercourses and to assess the risk of oxidation of the sediment at a reduced water supply/level. A review of control measures in the form of sampling, level measurements, etc. was performed on the basis of proposed measures/pumping.
ÅF also took on the role of technical expert in the main negotiation at the Swedish Environmental Court in connection with the operation.