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4. Water and Slurry Handling Systems and Environmental Protection <br />a) Coarse Ore Tunnel, Crusher Gallery, Decline and Mill Tunnel <br />The water handling system in the crusher gallery, mill tunnel, filter building and thickener is complex but it is <br />clearly shown in the views of Map 1. Almost all water is recycled through the 18,000 gallon process water tank <br />and the 18,000 gallon tailings tank in the filter building. Makeup water is provided from the coffer dam located <br />in the coarse ore bin tunnel. Water from selected areas of the mine are gravity and mechanically fed to this <br />coffer dam through several HDPE pipes using the main mine tunnel. Water is then gravity fed from this coffer <br />dam into a metal surge tank of dimensions 5' wide x 5' high x 10' long, located immediately near the coffer dam. <br />A small portion of the water is then fed to the crusher gallery, where it is used in dust suppression at the jaw <br />crusher, the cone crusher and the 3/8" screen. Water is also pumped up the decline into the mill tunnel where it <br />is piped to the 18,000 gallon process water tank in the filter building. From this tank, water is pumped back into <br />the mill tunnel where it is used in the ball mill, the flotation cells and filtrate tanks. The majority of the water <br />that enters the coffer dam in the coarse ore tunnel and then to the metal surge tank is pumped back to the <br />Yellow Rose drift, where a dam has been built to allow solids to settle out. The third outlet from the metal surge <br />tank is simply an emergency overflow pipe to the mine ditch located in the main tunnel. <br />No water, slurry or other liquids can leave the mill tunnel since it is graded at a 1.0% grade to the south, away <br />from the portal. Since the length of the tunnel is 288 feet to the electrical room, this provides excellent storage <br />of any spillage or pipe rupture, even if the sump pumps failed. The sumps and Gallagher pumps shown on Map 1 <br />are strategically located so that any water buildup on the mill floor is pumped back into the system of tanks. The <br />mill (and mine) receive line power, but a 1 Megawatt backup generator is located on the surface in case line <br />power is disrupted. Also, in the case of a power failure, no water would be delivered from the pumps to the mill, <br />so that the only water and/or slurry that could build up would be that which is already in the mill tunnel in the <br />flotation cells and filtrate tanks. The mill tunnel and the crusher gallery have concrete floors. <br />In the case of a pipe rupture or tank rupture in the mill, power would be shut off to the pumps and no significant <br />water volume could build up in the mill tunnel. As an even greater protection, if a very large volume of water <br />built up in the mill tunnel, it would spill over into the decline and flow down to the crusher gallery before coming <br />out the mill portal. There is an extremely large volume of storage in this tunnel and water cannot escape this <br />tunnel to the surface. The sump pumps in the crusher gallery pumps water back into the system so that no <br />discharge occurs. The coarse ore tunnel also drains to the crusher gallery which is the low point of the entire <br />mill. <br />All sump pumps are on automatic operation depending upon water level in the sumps. <br />Revenue Mill Certification Page 13 of 20 <br />