2020-02-07_PERMIT FILE - M2020007 (2)

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EXHIBIT G WATER INFORMATION Introduction The site is located about 3 . 5 miles north of Fort Lupton, Colorado. Please refer to EXHIBIT B -VICINITY MAP for the property configuration and the relationships to surrounding geological fea- tures . The site is bordered on the north by Weld County Road 22 . 5 and on the south by Weld County Road 20, on the west by the South Platte River and on the east by the neighboring agricultural proper- ties . There are two (2) ditches that cross the property from north to south in the western area - the Evans # 2/Platte Valley Canal and a landowner-owned irrigation return flow ditch (noted as the Cannon Return Flow Ditch on the permit maps) . There is one (1) ditch that crosses the property from north to south in the eastern area - the Platteville Ditch. None of these ditches will be disturbed by mining. In addition, the western and eastern areas of the mine are divided by U.S . Highway 85 and the Union Pacific Rail Road tracks . Based on regional groundwater studies and the experience gained by L.G. Everist, Inc . during numerous previous permit applications they have found that slurry wall liners mitigate any impacts to groundwater on nearby areas surrounding a lined reservoir. Addition- ally, the ditches, river and streams lying across or around the site will limit groundwater mounding or shadowing. If any significant groundwater changes do occur, they can be mitigated as discussed below. Mitigation Trigger Starting in October 2019, L.G. Everist, Inc . began to collect groundwater elevations from newly installed monitoring wells on and around the mine area to establish historic ground water elevations around and on the site . A 2-year period from October 2019 to September 2021 will be used as the baseline for triggering mitigation actions . Mining may have started by this time, but since the start is planned on an area that will not be lined, the baseline data needed for the areas that will be lined will be in place before installation of the slurry walls will begin. There are outside influences not caused by any mining operations of L.G. Everist, Inc . These outside influences that have been acting on the groundwater levels will continue to influence the groundwater levels and impact the baseline range and trigger point . The natural groundwater depths vary from 3 . 5 to 9 feet below the surface in Phases 1 and 2 when they were measured in March-2019 . The seasonal operation of the unlined irrigation return flow ditch that crosses the permit area on the west will affect groundwater levels and could help with any mitigation needs in the Phases west of the highway. Between the Platteville Ditch and the Railroad in Phases 4, 5, & 6, the groundwater depth varies from 3 to 24 feet below the surface, when measured in March-2019 . Groundwater depths can vary L.G. Everist, Inc. Ragsdale Reservoirs 27 February 6,2020