Apex Engineering served as project manager for design and implementation of an Anoxic Biotreatment Cell (ABC) for nitrate removal from excess mine water. This large-scale pilot system was designed to reduce the nitrate-nitrogen concentration from approximately 30 mg/L to less than 10 mg/L while treating up to 50 m3/hr (220 gpm) of water. Design goals were achieved in the year-long pilot test and a final report was issued. The Minera Yanacocha site, whose majority partner is Newmont Mining Corporation, is one of the largest gold mines in the world.
Photos of the Yanacocha denitrification system, operating at an elevation of 13,300 feet above sea level.
Here's a paper on this treatment system: