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the natural drainage located between the proposed operations and stockpile areas. Water <br /> running into Channel A and the natural drainageway will not contact mining operations. <br /> Water flowing in Channel A and then the natural drainage is diverted and protected. <br /> Channel B: Contact Water Pond Channel and Channel C: Ofsite Stormwater Diversion <br /> Channel diverts water into either the Contact Water Pond or the on-site detention and <br /> sediment control pond. These 2 channels and ponds prevent water encountering mining <br /> operations from entering the natural drainageway directly. The Offsite Stormwater <br /> Diversion Channel will be lined with 12-inch diameter riprap and stepped where steep <br /> slopes cause critical flow. <br /> Natural Drainage Flows (Basin E)— Storm event flows were calculated for the natural <br /> drainageway for culvert sizing. The existing 84-inch diameter culvert is shown to handle <br /> calculated flows for the drainage. Two new 84-inch culverts are proposed for the roads <br /> accessing the two proposed operational pads. One culvert per road crossing. The Offsite <br /> Stormwater Diversion Channel will increase flows in the natural drainage below the <br /> existing culvert as most of the flow from the Offsite Stormwater Diversion Channel <br /> historically into a smaller drainageway where the tailings facility will be located prior to <br /> discharging into the drainage between the operations and stockpile areas. <br /> Eastern Boundary Offsite Flows (Basins D1, D2, D3, and D4)— Storm event flows were <br /> calculated for each of the basins with a label beginning with "D". "M basins were <br /> delineated based upon topographic,proposed stockpile, and culvert locations. Culvert sizes <br /> and rundown aprons crossing the primary access road at strategic locations were based on <br /> calculated 100-year flows. Water exiting the culverts will now between the stockpile and <br /> laydown areas into the Ofsite Stormwater Diversion Channel before it enters the detention <br /> and sedimentation pond. Sediment will be removed in the pond before it is discharged onto <br /> the existing ground and travels through vegetation before entering the natural drainageway. <br /> There is no development planned for Basins D1, D2, D3, and D4 and no changes in <br /> historical flows are expected. <br /> Operations Area Site Impacts (Basin B) <br /> Two(2)operational pads,the processing plant and maintenance shop pads along with roads <br /> will be constructed in this area. The adit/plant pad will slope downward to the north at 2- <br /> percent and be 1.73 acres. The maintenance pad is 0.37 acres and will have a 1 to 2-percent <br /> slope away from the building. A processing plant will be built on the plant pad site. The <br /> area is bounded by the tailing's facility to the west, the contact water pond to the north, <br /> Contact Water Pond Channel to the east and the Offsite Stormwater Diversion Channel to <br /> the south. Water will run into either the contact water pond or the Contact Water Pond <br /> Channel, which discharges into the contact water pond. The contact water pond will be <br /> lined and is sized to capture water from the tailing's facility and operations area. There are <br /> no outlet structures for the pond. Water will be used for processing operations and prior to N <br /> any discharged, the water will be tested and shown to meet water quality standards before o <br /> it is discharged by a pump into the natural drainageway when not used for the processing 'CO <br /> plant. <br />