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EXHIBIT G <br /> Water Information <br /> Introduction <br /> The West Farm Pit is located in the northeast '/4, and the east '/2 of the northwest '/4, and the <br /> north 'h of the southwest '/4 of Section 33, and the south 'h of the southeast '/4 of Section 28, <br /> Township 22 South, Range 46 West of the Sixth Prime Meridian in Prowers County, Colorado. <br /> The proposed mining site is located approximately '/2 mile east of the City of Lamar, and <br /> approximately '/4 mile north of State Highway 50 as shown in Figure Exhibit G-1. The Arkansas <br /> River is approximately 1,000 feet north of the site, Willow Creek is adjacent to the southeast <br /> corner of the site, and the Lamar Canal is approximately 1,400 feet west of the site. The <br /> operation will consist of sand and gravel production and will impact the Arkansas River in the <br /> form of depletions due to evaporation and operational losses associated with mining. Mining of <br /> the West Farm Pit will last for approximately 15 to 30 years. Once reclamation is complete, a <br /> three cell reservoir will be created with a total surface area of approximately 159.5 acres. <br /> The depth to groundwater ranges from 10 to 24 feet. The site will be mined down to 40 to 70 <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 /> Arkansas alluvial aquifer. These impacts will cause river depletions that must be augmented. <br /> To enable dry mining at the West Farm Pit, 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 two phases are completely mined, but before the reclamation <br /> has begun on any given phase. The maximum size of dewatering trench will be 4,350 feet long <br /> and 5 feet wide, or 0.50 acres of exposed surface area. This water will be collected in a 50 foot <br /> by 100 foot discharge settling pond. After sediment has settled from the water it will be pumped <br /> into a farm ditch and discharged into the Arkansas River. <br /> As mining progresses, the dewatering trenches and discharge settling pond will shift as various <br /> cells are reclaimed. The gravel pit will be lined concurrent with mining per the reclamation plan. <br /> Water Requirements <br /> Water use at the West Farm Pit will include evaporation from exposed groundwater, dust control <br /> of 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 /> West Farm pit will include groundwater exposed in the dewatering trenches and discharge <br /> settling pond. The maximum exposed surface area at the site during mining is estimated at 0.61 <br /> acres. Prowers Aggregate Operators, LLC. will keep the site dewatered throughout the life of <br /> 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 60 inches for <br /> J&T Consulting, rowers Aggregate Operators,LLC. <br /> 8,Inc.. West Farm Pit—M-2008-078 <br /> DRMS 112 Permit Amendment Application <br />