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EXHIBIT G <br />Water Information <br />Introduction <br />The West Farm Pit is located in the the northeast'/4 and the northeast'/4 of the northwest 1/4 of <br />Section 33, and the south '/2 of the southeast '/ of Section 28, Township 22 South, Range 46 <br />West of the Sixth Prime Meridian, in Prowers County, Colorado. The proposed mining site is <br />located approximately 'h mile east of the Town of Lamar, and approximately '/4 mile north of <br />State Highway 50 as shown in Figure Exhibit G-1. The Arkansas River is approximately 1,000 <br />feet north of the site, Willow Creek is adjacent to the southeast corner of the site, and the Lamar <br />Canal is approximately 1,400 feet west of the site. The operation will consist of sand and gravel <br />production and will impact the Arkansas River in the form of depletions due to evaporation and <br />operational losses associated with mining. Mining of the West Farm Pit will last for <br />approximately 30 to 40 years. Once reclamation is complete, a reservoir will be created with a <br />total surface area of approximately 183 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 the Farm's irrigation lateral, which traverses the site, and discharged into the Arkansas <br />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. GP Ranches, LLC. 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 60 inches for <br />?; JsT Consulting, inc. GP Ranches, ! L <br />West Farm Pit <br />DRMS 112 Permit Application <br />23