ABSTRACT
At the Kristineberg mine site, N Sweden, a pilot-scaled facility has been constructed for the treatment of contaminated groundwater discharging from a tailing deposit. The acid and metal rich groundwater is led into a high conductivity zone and through serially connected tanks consisting of four treatment zones. Initial results indicate that acid neutralization succeeds in elevating the pH to 6. Ferrous iron decreased by 30% and sulfate by 25% during the first months, although significant sulfate reduction is not yet occurring. Sub-neutral pH, high flow rate and low temperature throughout the system may inhibit the growth of sulfate reducing bacteria (SRB). Adjustments are being made to the facility in order to reduce flow and promote the growth of SRB.
