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<br />the operator proposes a mitigation plan that is intended to restore groundwater elevations back to <br />historic conditions before lined reservoirs were constructed. <br />The operator proposes to install a French drain system around the perimeter of the property to <br />intercept groundwater flows and maintain an avenue to route the flows around the reservoir. <br />This French drain will be very similar to the field drains that are used by farmers to control high <br />groundwater in agricultural fields. An estimate of the flow in the aquifer indicates that a French <br />drain with a capacity of 2 cts would be adequate to maintain groundwater levels in the area. <br />Approximately 5,000 linear feet of 12"diameter perforated PVC pipe would be used with a <br />gravel encasement and geotex[ile cloth (see Figure G-1 ). The drain would be constructed [o a <br />maximum depth ranging of 8 feet and would be daylighted to allow for flows to escape as surface <br />water in the event that the aquifer has no capacity downstream of [he property. It is theorized <br />that in most situations, the downstream aquifer will have excess capacity due to the reservoir <br />liner construction and that flows in the drain will gradually return back to the aquifer through the <br />perforations and gravel drain. In normal conditions, there should be no[ water flowing at the end <br />of the drain which would protect groundwater users downstream and would not reduce available <br />supplies to either surface or groundwater users. <br />Project Water Requirements <br />The proposed mining operation will consume water front plant operations, minor evaporation <br />from exposed groundwater during dewa[ering operations, and moisture loss in materials <br />transported from the site. <br />The water losses will be accounted for in an approved Substitute Water Supply Plan (SWSP) <br />submitted to the State Engineers office. A copy of the approved plan will be submitted to DMG <br />when it is received. <br />Table G-1 summarizes annual consumptive use estimates <br />Table G-1 Annual Consumptive Use (acre-ft) <br /> <br />Descri lion Annual <br />Volume a <br />Evaporation 0.67 <br />Moisture Retained in Material 7.35 <br />Dust Control 0.80 <br />TOTAL: 8.8~ <br />