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• East of the West Geological Fault, groundwater levels drop significantly below the water levels in <br /> Little Turkey Creek, indicating that the creek recharges the groundwater system. This results in <br /> Little Turkey Creek losing surface water flow in the reach immediately downgradient(east)of the <br /> fault. Little Turkey Creek flows diminish to zero flow in the late summer and fall a few hundred <br /> feet east of the fault zone. <br /> • Groundwater quality data from the groundwater monitoring facilities at HRR were compiled and <br /> evaluated for chemical characteristics and signatures. The water chemistry data for groundwater <br /> in the granodiorite rocks west of the West Fault generally indicates a sodium-sulfate type with <br /> high total dissolved solids (TDS) compared with surface water. Water chemistry data for <br /> groundwater in the granodiorite rocks east of the West Fault that are being recharged by surface <br /> water in Little Turkey Creek, show very similar characteristics to surface water chemistry in this <br /> location with low TDS and a calcium-bicarbonate type. <br /> • Mining operations will be at least 100' south of Little Turkey Creek and at elevations at least 10' <br /> above the creek. Mining will not induce seepage from the creek. The runoff from the few side <br /> drainages that are impacted by mining will be conveyed to Little Turkey Creek via a network of <br /> channels and sediment basins, so that net flow to the creek will not be impacted. <br /> • Two existing seep areas within the proposed quarry area will be mined out, but water discharged <br /> from these seep areas will be intercepted by the mine, collected in drainage ditches, and directed <br /> to sediment basins before being released to Little Turkey Creek. <br /> • Based on the available geologic information and information provided by the State Engineer's <br /> office, 11 of the 13 domestic wells west of the quarry produce water from geologic fracture zones <br /> associated with the Little Turkey Creek drainage. The two wells not producing from the LTC <br /> fracture zone are north of the creek. One additional well location, permit #34643, is located <br /> outside of the more highly fractured zone, within the south ridge area, and this well location is <br /> suspected of being incorrectly recorded with the State Engineer and does not actually exist at the <br /> mapped location. The proposed quarry will not intersect the drainages and will therefore not <br /> directly interact with these more highly fractured zones. <br /> • Mining activity will intercept groundwater in the south ridge area, mostly in the form of seepage <br /> along the western and southern highwalls, is projected to result in mine inflows ranging from less <br /> than 10 gpm to about 50 gpm over most of 40-year mining operation, with a peak inflow of about <br /> 100 gpm at maximum excavation. Mine inflows will be collected in ditches and directed to <br /> sediment basins, before being released to Little Turkey Creek. Post-mining groundwater <br /> interception will be less than 20 gpm, and this water will flow to Little Turkey Creek via the post- <br /> mining reclaimed drainage topography. From a water balance perspective, there will be no net <br /> loss to the groundwater resource during active mining and post-mining periods. <br /> TRANSIT MIX-HITCH RACK RANCH <br /> HYDROGEOLOGY AND IMPACT ANALYSIS <br /> 1-2 <br />