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' Mine Pits <br />The Project was anopen-pit precious meta] mining operation permitted with two pits as <br />shown on Figure 1. Waste rock taken from the East Pit was deposited in the Waste Rock <br />C facility. The East Pit was backfilled with waste rock from the West Pit mine <br />' operations. Backfill operations fully backfilled the East pit to a topographic elevation <br />that allowed the reclamation recontouring to blend the backfilled facility with the <br />' adjacent undisturbed topography. Thus leaving no topographic depression. <br />' The West Pit is the deeper of the two permitted facilities. Similar to the East Pit, the <br />West Pit has been partially backfilled to allow surface stormwater drainage and wildlife <br />' habitat enhancement within the pit area. Waste rock from the western portion of the <br />West Pit was concurrently backfilled in the lower portions of the pit (southeastern <br />portion) and, following completion of final mining operations, waste rock from Waste <br />Rock Facility B was transported and end dumped to complete the partial backfilling <br />operation. The southern and central portions of the pit have been backfilled to an <br />elevation facilitating stormwater drainage, while the northern portions of the pit remain <br />as highwall faces terraced by wide, relatively flat benches. During operations, <br />precipitation falling within the pit and groundwater seepage encountered during mining <br />was collected in sumps and then pumped to the tailing disposal area where it was <br />recycled to the mill operations. <br />Since the finalization of mining and backfilling operations, groundwater removed as the <br />result of mine dewatering operations has been allowed to rebound back into the pit. This <br />inundation of the waste rock with groundwater has resulted in elevated concentrations of <br />total dissolved solids (TDS), sulfate, fluoride, and manganese in groundwater in and/or <br />adjacent the immediate area of the West Pit. The elevated concentrations of sulfate, <br />manganese, TDS, and fluoride have resulted from the dissolution of secondary salts that <br />formed on the outer surfaces of the backfilled waste rock during the period of time the <br />material was exposed to the atmosphere (i.e., material extraction, temporary storage, and <br />transport). As the result of these elevated concentrations, BMRI constructed and <br />commissioned a water treatment facility to treat groundwater from or within the West Pit <br />facilities. The water treatment facility consists of three geomembrane lined ponds and a <br />Battle Mountain Resources, lnc. Telesto Solutions, lnc. <br />,~, mv,~o.m~~e. maws:me~~Pm~.e~ 3 May 3. 2002 <br />