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6.4.7 EXHIBIT G -WATER INFORMATION <br />Groundwater <br />The groundwater aquifer within the permit boundary is the sand and gravel layer <br />which is the major water bearing strata in the area. The gravel occurs at a <br />thickness of approximately 10-15 ft in the area. Local groundwater flows from <br />the north and west through the gravel and discharges to the Big Thompson <br />River. The groundwater in the gravel is confined north of the proposed gravel pit <br />and unconfined in pit area south to the river. <br />An upper perched aquifer occurs north of the permit area. This aquifer is <br />composed of an upper silty sand layer (SM) includes localized areas of clay (CL). <br />This layer is approximately 12 ft thick just north of the permit area and becomes <br />thicker rapidly to the north concurrently with the rise in elevation. The layer is 35- <br />40 ftthick near under the area where the Greeley Loveland Canal occurs. The <br />Greeley Loveland Canal runs through the upper layer approximately 420 ft north <br />of the proposed pit at an elevation of approximately 4940. Water leaking from <br />the ditch daylights in groundwater seeps along the hill slope just north of the <br />proposed pit (see Sheet 1). It appears that water from the ditch seeps do not <br />reach the proposed gravel pit in the upper layer because the upper soils were not <br />saturated at the time of observation well drilling (July). It is however, likely that <br />some seepage water is transmitted vertically to the lower gravel layer north of the <br />proposed pit area. Water in this layer is unconfined (surface at atmospheric <br />pressure). Approximate groundwater table elevation contours are shown in <br />Exhibit C-1 which are based on.data from 5 observation wells also shown in <br />Exhibit C-1. A database search was conducted at the Office of the State <br />Engineer for all wells within 600 ft. There were no alluvial groundwater wells <br />found within 600 ft of the Gardels Pit <br />Project Water Requirements <br />Dewatering pump rates are expected to be between 200-300 gpm. The largest <br />area to be dewatered at any one time will be Cell D, which is approximately 11 <br />acres. Annual monthly water depletions due to mining are given in Table G-1. <br />Replacement water will come from City of Loveland fully consumable efFluent for <br />which Coulson holds an ongoing lease (see Attachment G-1 ). The existing water <br />right for the property is the decreed Osborn Irrigation System seepage water right <br />(CA10077), which includes the groundwater seeps just north of the pit areas. <br />Surface Water <br />Onsite and surrounding water features are shown on Exhibit C-1. The major <br />surface water feature is the Big Thompson river that flows to the east. As noted <br />in the previous section, groundwater seeps daylight before reaching the <br />proposed pit area in the west. There is an irrigation ditch that runs down the <br />middle of the east pit area. This ditch routes a groundwater seep (Osborn <br />Irrigation System) just north of Cells C-D and has been used historically for <br />irrigation of the Gardels farm. During mining, the seep water will be allowed to <br />flow into the pit and will be pumped out with the groundwater. The reclamation <br />Gardels Pit Rev AR-1.0 <br />Regular 112 Permit Application <br />