This study was carried out to monitor the effects, if any, of the former Topley Concentrate Shed Site ("Topley Site") on concentrations of dissolved and total metals and other parameters and on aquatic life in the Bulkley River. The study included three months of water quality monitoring, chemical and toxicity testing of river sediments, measurement of metal accumulation in native mussels and evaluation of overall aquatic ecosystem health through determination of the composition of the benthic fauna community upstream and downstream of the Topley Site.