080121-08MN006-Sabina Hackett River Project Proposal ... - NIRB

Identification of Potential EnvironmentalEffects and Proposed Mitigation• Discharge or leaking from the Tailings Management Facility (alteration to the productivecapacity of fish habitat);• Lake dewatering (loss of fish habitat);• In-stream construction of dams, culverts, bridges (loss of fish habitat and limits tomigration);• Ammonium nitrate fuel oil (ANFO) use and storage (release of deleterious substance tofish habitat);• Runoff from waste rock piles, stockpiles, roads (release of deleterious substance to fishhabitat);• Disposal of open pit and underground sump water (release of deleterious substance tofish habitat);• Fuel transport and handling (release of deleterious substance to fish habitat);• Disposal of treated sewage effluent and/or sludge (nutrients, release of deleterioussubstance to fish habitat); and• Dust-generating activities (e.g., construction, road and airstrip use) (sedimentation andsmothering of benthos and fish eggs, leading to a decrease in productive capacity of fishhabitat).The loss of fish habitat will occur due to the development of the TMF, the dewatering of CampLake, and works in or around water (e.g., installation of dams, culverts, bridges, etc.). Theseactivities will result in the harmful alteration, disruption or destruction (HADD) of fish habitat.Dust-generating activities include the construction of roads, the airstrip, dams, buildings, and theongoing use of roads and the airstrip. These activities can introduce particulate material (such asTSS, aluminium, other metals associated with rock material being used) into surrounding surfacewaters. The use of ANFO as an explosive to break apart rock can leave nitrogen residues onrock, which is easily dissolved in water and introduced to surrounding surface waters. Highconcentrations of nitrate, nitrite, and ammonia can all be toxic to aquatic life, but can be limitingto aquatic life at extremely low concentrations.Runoff from waste rock piles, ore stockpiles and roads could be of poor quality. Water could beacidic, neutral, or alkaline, and contain high metals and high levels of nitrogen compounds.Concentrate is the end product of the mine, and will contain high metal concentrations. Fugitivedust from storing, handling or transporting the concentrate could introduce metals intosurrounding surface waters. Fuel handling and use on site could potentially cause theintroduction of hydrocarbons to surface waters.The in-stream construction of dams, bridges, and culverts could potentially disturb lake andstream sediments, and cause high TSS (and possibly high TP and metals) to be introduced tosurface waters.January 2008 Hackett River Project – Project Proposal Sabina Silver CorporationReport Version B.1 7–25 Rescan Environmental Services Ltd. (Proj. #833-2)