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1 <br /> <br />' Groundwater <br />Test holes in the deposit and groundwater lakes north of the Wellington Downs site indicate the <br />alluvial groundwater aquifer is encountered at average depth of 10 fee[ below the surface. In order <br />to mine the entire deposit dry, it will be necessary for Connell to dewater. <br />' Connell has located two discharge points. When excavating at the south end of the property they <br />will discharge into Mallazd Creek, south of County Road # 36. While excavating on the north end <br />' of [he property they will pump water into a culvert which dischazges into the Box Elder Ditch, east <br />of I-25. These proposed discharge points aze located in Exhibit C. <br />t Dewatering sumps or trenches will be dug in the pit bottom to capture the groundwater flow and <br />reduce [he amount of suspended solids discharged. Connell will obtain the appropriate discharge <br />' permits from the Colorado Department of Health prior to any dewatering activity. <br />The proposed reservoir will be created by placing a compacted overburden clay liner along the <br />' shorelines of the excavated pits (see Exhibit F). Placement of the compacted loner along the <br />shoreline will eliminate groundwater inflow into the pit. The pit will be mined down to bedrock and, <br />therefore there will be no infiltration through the bottom of the pit. The reservoir will be exempt <br />from regulations of Senate Bill 120 since there will be no groundwater depletions. <br />The Water Court and the SEO have set a standazd for the construction of gravel pit reservoirs. The <br />' acceptable limit of seepage is ]gpm per 100 liner feet of reservoir shoreline. The Wellington <br />Downs reservoir will have approximately 7360 feet in perimeter and consequently will have an <br />allowable 73.60 gpm seepage. This equates to 118.72 acre-feet of seepage annually. <br />After the construction of the reservoir liner, the pit will be examined by the SEO's for seepage. If <br />' the pit on not within acceptable ranges, localized reconstruction of problem areas will be done. <br />Water Use <br />' The quantities of water used is expected to remain the same as Connell's present operation. Water <br />use at the site will include evaporation from wash ponds, water retained in the material removed <br />from the site, water used for dust control for haul roads and stockpiles. <br />Evaporation from the site during mining will include water exposed due to the dewatering operation <br />' and water pumped from the pit to settling ponds used for the washing operation. Approximately .3 <br />acres of water will be exposed in the dewatering trenches and ponds. <br />' The annual evaporation is 39 inches at the Wellington Downs site. The precipitation at the mine site <br />is estimated to be the same as that found at the neazest weather station which is located in Fort <br />Collins. The annual mean precipitation here is 14.7 inches. <br />1 <br />