2020-05-08_PERMIT FILE - M2020007

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Exhibit G Water Information (cont) influence the groundwater levels and impact the baseline range and trigger point . The natural groundwater depths vary from 3 . 5 to 8 . 8 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 significantly through seasons and years, depending on many influences, including, climate, precipitation, irrigation, other pumping rights, and much more . L .G. Everist, Ines . experience on other mines in the South Platte River valley indicates that groundwater levels can fluctuate as much as 7+ feet depending on the season. In a normal mitigation trigger plan, the trigger limits would be set at 3 foot change plus or minus change over a 3-month average . Realistically, in this case the trigger number should be based on a 3-foot change determined by a line that approximates a up or downward trend of the water table and considers outside impacts such as, drought , adjoining mining activities, storm events or decreased irrigation activities . At the current time, there is no mounding mitigation plan for when the water table increases . We do not expect this to be a problem where the slurry walls are in close proximity to a flowing water body like the ditches, return flow ditch and the South Platte River. Mounding would be controlled by those water surfaces and it would only affect Cannon Land Company areas around the reservoirs . On the east side of the Platte Valley Canal , the ground-water table averages 11 feet deep and there are enough unlined areas crossing thru the lined reservoirs to allow for some increase without impacting surface features . In the eastern area groundwater averages 12 feet below the surface, there are numerous, gaslines and road corridors that would allow ground water to bypass the lined areas . The mining operation will have minimal effect on the South Platte River in the form of minor groundwater depletions due to evaporation and water uses associated with mining. The depletions to the South Platte will be mitigated thru a temporary Substitute Water Supply Plan (as required and approved by the Division of Water Resources) to prevent injury to the vested senior water rights . The reclamation plan proposes the creation of 8 (or fewer) slurry wall lined reservoirs that will not be hydraulically L G. Evenst,Inc Ragsdale Reservoirs May 5,2020 28