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EXHIBIT G -WATER INFORMATION <br /> This information provided in this Exhibit is intended to satisfy the requirements outlined in Section <br /> 6.4.7 of the Colorado Mined Land Reclamation Board Construction Material Rules and <br /> Regulations: <br /> (a) Locate on the map(Exhibit C) tributary water courses, wells, springs, stock water <br /> ponds, reservoirs and ditches <br /> The site is 0.6 miles east of the Saint Wain River. Please refer to Exhibit C for locations of <br /> water courses in close proximity to the site, including wells, springs, stock water ponds, <br /> reservoirs and ditches. <br /> (b) Identify all known aquifers <br /> The site is underlain by a shallow alluvial aquifer, typical of its position upgradient of the St. <br /> Vrain River. <br /> (c) Show how water from dewatering operations or runoff from disturbed areas,piled <br /> material and operating surfaces will be managed to protect against pollution of either <br /> surface or groundwater both during and after the operation. <br /> Please refer to the Mining Plan Map in Exhibit C of this application. Dewatering operations <br /> will run continuously during the mining of the freshwater and silt ponds, then intermittently <br /> during mining within the slurry walled cells. Dewatering water will be pumped to the <br /> discharge pits shown on Exhibit C. Mine areas will drain internally. Uncontrolled releases of <br /> surface water in disturbed areas will not occur. Stormwater collected in the active mine area <br /> will be managed through the dewatering system. The operator will apply for a Colorado <br /> Department of Public Health and Environment Discharge permit and will maintain a <br /> Stormwater Management Plan and Spill Prevention Control and Countermeasure Plan. <br /> (d) Estimate project water requirements including flow rates and annual volumes for the <br /> development, mining and reclamation phases of the project. <br /> Water needs estimated below provide for sustained production as detailed in the Mining <br /> Plan. The Operator will adjust water supplies to account for actual demand, avoid waste, <br /> and continuously comply with laws and regulations of the Division of Water Resources and <br /> any other water agency having jurisdiction over the operation. <br /> Projected Use And Consumption: Annual evaporative depletions will be the evaporation <br /> from up to 5000 feet of 4-foot wide de-watering trench, located inside of the slurry wall. The <br /> total area of exposed water is 0.5 acres. The gross annual evaporation at the Nix Gravel <br /> Mine aggregate mine is 42 inches according to NOAA Technical Report NWS 33, <br /> Evaporation Atlas for the Contiguous 48 United States. Monthly evaporative losses are <br /> determined using percentages specified by the State Engineer's Office for locations below <br /> 6,300 feet. The nearest weather station is in Longmont where the average annual <br /> precipitation is 15.08. Effective precipitation, that part of historical precipitation which was <br /> consumed by native vegetation on land to be covered by water surface, is conservatively <br /> estimated to be 70 percent of the total precipitation. The annual average effective <br /> Ready Mixed Concrete Company—Nix Gravel Mine—MLRB 112 Permit Application <br /> Exhibit G-1 <br /> Page 23 of 126 <br />