Approximately 800 000 m3 of acid mine drainage (AMD) is generated per year at the Equity Silver Mine southeast of Houston. This AMD would have devastating effects on the Bulkley River if it was allowed to flow untreated from the property for a prolonged period of time. In order to develop an understanding of the consequences to the Bulkley river of this possibility, bioassays were set up using raw acid mine drainage and Bulkley River water. It is confirmed that perpetual treatment of AMD at the minesite will be necessary to protect water quality and the sustainable economic benefits derived from the river. Prepared for the 11th Annual Mine Reclamation Symposium April 8, 9, and 10, 1987.