New Britannia Mine in Snow Lake, MB is a historical gold mining and processing site currently under care and maintenance. Arsenic and copper are elevated in the water column and sediment. The goal was to better understand whether previously observed statistical differences between reference and exposure populations was due to mine effluent, historical contamination or natural variability.

The study evaluated bioavailability and uptake from water and sediment into aquatic biota and, assessment of potential mine effluent related effects. Extensive water quality analyses and arsenic speciation in porewater, and benthic invertebrates living near the sediment water interface were analyzed. This was integrated with traditional benthic and fish community surveys, toxicity testing of site water and enzymatic work in fish.

Important results from this study showed that current effluent  quality, nor historical arsenic or copper in the sediment appear to be causing observed effects. Minor differences observed in benthic invertebrates and, overall stimulatory effects on fish were due to increased nutrient resources in the exposure area.