2016-11-23_PERMIT FILE - M2016080 (4)

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EXHIBIT G WATER INFORMATION 1. General Mining of a dredge pile like the Trout Valley Ranch will involve minimal effects on local ground water and surface water. In general, any offsite water encountered by operations will be rerouted away from onsite activities to protect its quality. Surface water in the immediate vicinity of mining activity will be managed within the disturbance area by excavation highwalls. Mining will only occur above the static water table. 2. Surface Water The Middle Fork of the South Platte River is located over 200 feet northeast of the mining area. Most surface water runoff drains through the permeable dredge piles on the north end of the site, or flows into the wetlands along the river from the south end of the site. Provisionally identified wetlands, as identified by the US Fish and Wildlife Service National Wetland Inventory, are shown on Map C-1. Map C-1 shows the pre-mining drainage patterns, Maps C-2 &3 show the drainage patterns during various stages of mining, and Maps F-1 &F-2 show the drainage pattern expected in each reclamation stage. The 100-year floodplain for the South Platte River is not affected by the mining operation, as the operation takes place well above it. The extent of the 100-year floodplain is shown on Map C-1. 2.1 Runoff Water Handling Offsite drainage from the west and north is intercepted either by the Platte River or by highway ditches. On site drainage mostly passes through the existing dredge piles on site,which drain well due to their reduced fines content versus the native and undisturbed material. The run-off calculations below do not account for the reduced fines content of the dredge piles, and treat all of the pile area as disturbed mining land. This gives a conservative overestimation of the pre-mine runoff scenario. Trout Valley Ranch November 2016 G-1 <;ret I.ewicki and Associates,PLIA