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EXHIBIT G Water Information General Mining at the Duckworth Pit will intercept shallow groundwater, which lies from 3 to 6 feet below the current ground level. Deeper bedrock aquifers that underlie the site will be unaffected by the mining operation because of the shallow depth of excavations. Please see enclosed Duckworth Pit Groundwater Study. Upon completion of mining, two ponds will remain unsealed for recreational and wildlife purposes. The resulting ponds will cover an area of approximately 37 acres. Local surface water ponds, ditches, water courses, and tributaries are shown on the pre- mining map. The nearest water course is Idaho Creek. No impact to Idaho Creek is expected as a result of mining. There are no wells located within 600 feet of the proposed Duckworth Pit. Please see enclosed Gravel Well Permit Application. Potential Water Resource Impacts The Duckworth Pit sand and gave] operation will have minima] impacts on the water resources in the area. The nearest domestic wells are part of the St. Vrain and Left-Hand water service area. Similar wells in the area are in closer proximity to other existing sand and gravel mining activities and are therefore not likely to be impacted by Duckworth operations. Please refer to Duckworth Pit Groundwater Study. A portion of the Smith and Emmons ditch will be relocated to facilitate mining. After sand and gravel excavation, compacted overburden and/or sandy siltstone bedrock will placed along pit walls to minimize impacts to nearby water resources. Discharge Permits The proposed mine will be dewatered and operated as a dry mine. Alluvial groundwater from pit dewatering will be discharged into Lighthouse Cove and Idaho Creek. The estimated discharge rate during dewatering is 1,127 gpm and 1,141 gpm for the winter and summer periods, respectively. The applicant has a Colorado/NPDES discharge permit for the pit and will discharge in accordance with permit conditions. Surface Water Management Please see the enclosed Storcnwater Management Plan. Consumptive Water Use The total annual operational losses due to the mining operation during the first two yeazs at the Duckworth Pit are projected to be 26.9 acre-feet. This includes evaporative losses, product water retention, and dust control. Please refer to Application for Substitute Supply Plan for additional information and calculations. Duckworth Pi! OMG /11 Permi7 Page IS of 49