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R!fIe ira,je, P, I #; May 2022 <br /> processing facility (800 -1,500 feet depending upon the mining location), where the material <br /> will be stockpiled for washing, processing, and subsequent sale. <br /> 1.1.8.3.2 Water Handling <br /> Any agricultural return flows in the tailwater channel, which are estimated at<2 cubic feet per <br /> second (cfs) during peak irrigation season, will be discharged into the pond, where they will <br /> mix with the alluvial aquifer and migrate laterally through the permeable gravels into the larger <br /> Colorado River water table. Given the minimal flows in the ditch, the large size of the pond <br /> (estimated at approximately 6 acres within one year), and the highly permeable nature of the <br /> gravel, the agricultural return flows will have a negligible effect on water levels in the pond. As <br /> excavation proceeds, the tailwater ditch will be subsumed into the expanding pond <br /> boundaries, until under final conditions the discharge point of the ditch to the pond will be <br /> located where the ditch enters the eastern boundary of the property. <br /> No other changes to irrigation return flows are proposed, and no additional water handling <br /> activities are included. Scott will comply with the State Engineer Office's (SEO) rules and <br /> regulations regarding any water depletions that may also occur during mining operations from <br /> water lost due to evaporation and water used for dust suppression. <br /> 1.1.8.4 Reclamation (Phase 4) <br /> The entire extent of the Permitted Area will be restored back to natural conditions upon <br /> completion of mining, including the removal of all temporary structures (office, vault and haul <br /> toilets, potable water, screen, crusher, equipment). Reclamation will generally proceed in <br /> concert with the excavation since the expansion of the pond boundaries will make later access <br /> to the perimeter of the mine difficult. A six-foot wide fringe of 5:1 slope will be left at the inner <br /> edge of the perimeter berm and planted with wetland reclamation species. The pond surface <br /> will be in direct contact with the Colorado River's water table, and the pond surface elevation <br /> will rise and fall in concert with the river level. The intention is for the six-foot wide perimeter <br /> fringe to be nearly inundated during high-water periods as the water table rises, and then to <br /> be progressively exposed as the water table drops during the growing season. The remainder <br /> of the pit slope to the bottom of the pond will be graded at approximately 3:1, not to exceed <br /> 2:1. This reclamation design follows County standards for gravel mine reclamation (LUC <br /> Section 7-1002.H). This design is not intended to provide formal wetland compensatory <br /> mitigation per USACE standards, as no impacts to wetlands are proposed. <br /> The perimeter berms and the Operations Area will be resurfaced with topsoil and revegetated <br /> with approved seed mixes as the upland reclamation area (totaling 5.83 acres). The wetland <br /> slope fringing the pond is approximately 0.79 acres, and under final conditions the surface of <br /> the pond is expected to be 12.56 acres. Note that the total acreage reported slightly exceeds <br /> 19.00 acres because the median elevation of the pond will inundate a portion of the wetland <br /> slope fringe. <br /> See Section 2.12 for additional information regarding reclamation of the property. <br /> 1-14 <br />