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EXHIBIT G <br />Water Information <br />Introduction <br />NCCI Pit #1 is located in the East'/: of Section 24, Township 2 North, Range 67 West, in the 6th <br />P.M, in Weld County, Colorado. The proposed mining site is located between the Lupton <br />Meadows Ditch and the Lupton Meadows East Ditch, approximately '/s mile west of the South <br />Platte River as shown in Figure Exhibit G-1. The Lupton Bottom Ditch is approximately '/. mile <br />west of the site, and Sand Hill Lake lies approximately Y=mile west of the site. The operation will <br />consist of sand and gravel production and will impact the South Platte River in the form of <br />depletions due to evaporation and operational losses associated with mining, Mining of the <br />NCCI Pit #1 will last for approximately 15 years. Once reclamation is complete, a reservoir will <br />be created with a total surface area of approximately 100.6 acres. <br />The depth to groundwater ranges from three to seven feet. The site will be mined down to 30 <br />feet, thus exposing groundwater to the atmosphere. This exposed groundwater, along with the <br />operational losses associated with the extraction of sand and gravel deposits, will impact the <br />South Platte alluvial aquifer. These impacts will cause river depletions that must be augmented. <br />To enable dry mining at NCCI Pit #1, there will be dewatering trenches around the various <br />phases of the site. These dewatering trenches will change in length throughout mining. The <br />maximum length will occur when NCCI is mining Phase 8. The maximum length of trench will be <br />7,040 feet long and 3 feet wide. This water will be collected in a 100 feet x 200 feet process <br />water pond. Water from this pond will be used for washing of the mined material. Water exiting <br />the wash plant will be carried by a 1,073 feet x 6 feet trench to a 0.5-acre sedimentation pond. <br />After sedimentation, this water will be returned to Little Dry Creek where it flows back to the <br />South Platte River. <br />As mining progresses, the dewatering trenches will shift as various cells are reclaimed. The <br />gravel pit will be lined concurrent with mining per the reclamation plan. <br />Water Requirements <br />Water use at the NCCI Pit #1 will include evaporation from exposed groundwater, dust control of <br />haul roads and stockpiles, and water retained in material removed from the site. <br />Evaporative Loss <br />Evaporative losses are dependent on the exposed water surface area, which may shift <br />throughout the mining operation, but will not exceed the maximum. Exposed surface area at the <br />NCCI Pit #1 will include groundwater exposed in the dewatering trenches, process water pond <br />and sedimentation pond. The maximum exposed surface area at the site during mining is <br />estimated at 1.6 acres. NCCI will keep the site dewatered throughout the life of the mine. <br />Evaporation data was taken from NOAA Technical Report NWS 33, Evaporation Atlas for the 48 <br />Contiguous United States. The annual gross evaporation was determined to be 45 inches for <br />this location. Monthly evaporation percentages are established by guidelines set by the State <br />Engineer's Office. To determine precipitation, data from the National Weather Service for both <br />M-2001-107 <br />NCCI Pd #1 <br />DRMS 712 Permit Amendment <br />41 <br />