Nitrates update – managing our impacts through bioremediation

We continue to strive to reduce the amount of nitrates released from our mining processes, while actively pursuing innovative ways to mitigate their impact. Our blasting practices and procedures continue to be refined in 2017 to limit the volume of nitrates released into the environment.

Our bioremediation pilot project has proven to be effective in the treatment of nitrates, and baseline studies continue to be conducted in order to establish effective practices. Though not yet at a stage where upscaling can take place, feasibility studies are being planned and we are tentatively excited about the potential of this innovative approach.

In 2017, it was decided to halt fertigation trials, which were proving to be costlier and less efficient than the bioremediation trials. Extreme weather conditions also hamper fertigation for much of the year, presenting challenges to its eventual upscaling.

Our leach tests were ongoing in 2017. Bulk rock samples were collected, at intervals across the blasting process, for further analysis. The rock samples are then doused with a fluctuating volume of water over a set period of time, in order for us to understand the leaching characteristics of nitrate contained in these rock samples. The results of this testing are proving invaluable in providing context for the efficacy of our interventions and have been responsible for the design of models to assist in the limitation of nitrate pollution from blasting.