2023-08-03_PERMIT FILE - M2023025 (32)

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EXHIBIT G Water Information Introduction IHC Scott proposes to mine in the land located in the parcel of land situated in the northeast 1/4 of Section 24, Township 4 North, Range 67 West of the 6th Principal Meridian, in Weld County, Colorado. The proposed mining site is located within the Town of Milliken town limits. CR 46 is north of the property and an access road from the property connects to CR 46 near the intersection of CR 46 and CR 25. The South Platte River is adjacent to the property and approximately 880 feet south of the site on the south side of the permit boundary and 180 feet from the east side of the permit boundary. The operation will consist of sand and gravel production and will impact the South Platte River in the form of depletions due to evaporation and operational losses associated with mining. Mining of the Bernhardt Sand and Gravel Pit mining site will last for approximately 11 years. Once reclamation is complete a reservoir will be created with a total surface area being 92.35 acres. The depth to groundwater ranges from 3 to 7 feet seasonally within the permit boundary (measured in MW-1 through MW-5, See the attached piezometer measurements table). The site will be mined down to a depth of 37 feet at the deepest depth thus exposing groundwater to the atmosphere. This exposed groundwater, along with the operational losses associated with the extraction of sand and gravel deposits,will impact the South Platte alluvial aquifer. These impacts will cause river depletions that must be augmented. Groundwater will be exposed during the mining once the mining depths reach an elevation of approximately 4713.8. To enable dry mining at the Bernhardt Sand and Gravel Pit mining site, there will be dewatering trenches around the perimeter of Phase 1. These dewatering trenches will change in length throughout mining. The maximum length will occur when Phase 1 is completely mined. The maximum size of dewatering trench will be 5,430 feet long and 5 feet wide, or 0.62 acres of exposed surface area. water will be pumped into dewatering ditch, which traverses the site, and ultimately into the South Platte River. As mining progresses, the dewatering trenches will shift as mining slopes are reclaimed. The gravel pit will have a slurry wall liner being constructed as mining commences in Phase 1. Water Requirements Water use at the Bernhardt Sand and Gravel Pit mining site will include evaporation from exposed groundwater, dust control of haul roads and stockpiles, and water retained in material removed from the site. Evaporative Loss Evaporative losses are dependent on the exposed water surface area,which may shift throughout the mining operation, but will not exceed the maximum. Exposed surface area at the Bernhardt Sand and Gravel mining site will include groundwater exposed in the dewatering trenches. The IHC Scott,Inc. J&T Consulting,Inc. Bernhardt Sand and Gravel Pit V I DRMS 112 Permit Application