2015-02-27_REPORT - M1982020 (3)

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10 SURFACE WATER CONTROL AND CONTAINMENT FACILITIES The permit area is located at the top of a topographic divide, out and away from any major drainages and on relatively gentle slopes. All designated chemicals are stored within the mill building, which has sufficient designed secondary containment capacity to retain any volumes of materials the might be spilled. All chemicals are purchased in and transported using DOT approved containers, with those containers being placed in their proper storage areas within the mill. The operator has standard procedures for cleanup of spills that might occur during transport and handling. The material contained in the Lucky Strike vein, and the country rock adjacent to it, is dominantly made up of silica minerals which have been found to contain only very low concentrations of sulfide minerals. Testing has found the materials to be non -acid generating. Thus if a storm event might occur, no acid generating or acid forming materials would be present to impact the environment. The map (Stormwater Runoff Map) is included showing the location of stored chemicals, fuels, and ore materials. Fuel storage facility consists of a 10,000 gallon steel storage tank set in a concrete secondary containment below a roof to keep out precipitation. The secondary containment structure has storage capacity to hold 13,800 gallons of product, or 138 percent of the capacity of the tank. The mill building is used to store all milling - related chemicals and reagents. Since the building is roofed there can be no degradation of the containers due to weather. The release of any solid reagents within the structure would be collected from the floors using appropriate tools. The main floor is concrete. The release of fluids in the quantity described in the plan (one individual container) would be retained on the floors within the building. The ore storage area is located inside the general storm water containment area, and surface flow generated would generally be retained immediately within the pad area by the berms. In the event of a large rain and minimal stored ore, surface water would migrate northward toward the tailings ponds as shown. Modeling indicates that it is unlikely that the 100 -year storm event would produce more than very minimal transport of materials. Storm water containment for the permit area includes the primary and secondary tailings pond areas, for which the current total calculated storage capacity is calculated to be 375,000 cubic feet. The volume of the combined storage ponds is currently approximately 40 times the total volume of runoff generated by the calculated 100 year 24 -hour storm event. Dikes and berms 13