Long Lake Containment Facility Nitrate In Situ Treatment Test, EKATI Diamond Mine (BHP Billiton, April 2012)

This report documents the 2011 Phase IV nitrate in situ treatment test at the Long Lake Containment Facility (LLCF) of the EKATI Diamond Mine, in which monopotassium phosphate fertilizer (4.3 tonnes) was added to Cell D between July 29 and August 20 to stimulate phytoplankton growth and biological uptake of elevated nitrate concentrations. Although the test stimulated phytoplankton blooms, there was no significant reduction in the calculated nitrate load of Cell D over the 2011 open-water season; however, nitrate concentrations did not increase despite continued upstream loading.