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Jerry Schnabel, Bob Stabo <br /> July 11, 2016 <br /> Page 8 <br /> Transit Mix has indicated that all existing drainages will be maintained. Although the natural <br /> drainage divide between Little Turkey Creek and Deadman's Creek will be mined through,a berm <br /> is proposed to maintain the same physical drainage divide during mining and through the <br /> backfilling and reclamation processes. <br /> The two observed springs within the mining area which drain to Little Turkey Creek are likely <br /> shallow seeps draining precipitation from the north facing hillslope. If the seeps continue to flow <br /> throughout mining, the flow will be controlled such that it continues to return to Little Turkey <br /> Creek. If the seeps disappear during mining, then they were shallow and purely fed by <br /> precipitation. Since the drainages will not be altered, the precipitation that fed the seeps will <br /> continue to flow to Little Turkey Creek as well. Transit Mix does not expect any slope stability <br /> issues associated with the seeps. <br /> Ground Water System Cross Sectional Depiction <br /> Comment: The CDRMS has requested cross sections of the proposed mining area that depict <br /> subsurface ground water conditions showing the primary ground water aquifer systems to the east <br /> and west of the thrust faulting, the relationship between the floors of the proposed mining areas <br /> and the shallow ground water in the drainages and how Little Turkey Creek interacts with the <br /> mapped alluvial deposits to the east of the proposed mining areas. <br /> Response: Transit Mix has prepared several cross sections to address the CDRMS questions <br /> including two cross sections perpendicular to the north-south oriented thrust faults that separate <br /> the granitic material from the sedimentary material and two cross sections perpendicular to Little <br /> Turkey Creek and Deadman's Creek showing the relationship of the mined pits to the creeks and <br /> their associated alluvium. The locations of the cross sections are located as presented in Figures <br /> C-13 and C-14. <br /> Cross sections A-A' and B-B', both perpendicular to the north-south oriented faulting,present the <br /> relationship between the granitic material, the north-south oriented faulting and the sandstone <br /> aquifers to the east of the faulting. Included in the cross sections are potential water table <br /> conditions across the area. Cross section A-A' includes a depiction of conditions beneath Little <br /> Turkey Creek where it is underlain by quaternary material. As indicated, Little Turkey Creek is a <br /> losing stream that eventually ceases to flow as surface water due to the infiltration of flow into the <br /> quaternary material. <br /> Cross Sections C-C' and D-D', both perpendicular to Little Turkey Creek and Deadman's Creek, <br /> show the relationship between the creeks, their associated ground water and the lowest elevation <br /> of the proposed mine floors. As indicated,Little Turkey Creek is essentially a losing creek through <br /> the granite material with water level elevations in the adjacent granitic material consistent with the <br /> elevation of the creek. Mining in the Little Turkey Creek drainage will remain above the elevation <br /> of the creek and the ground water table and will not interact with ground water. As indicated,the <br /> ground water table beneath Deadman's Creek is also expected to be below the lowest elevation of <br /> mining and the mining along Deadman's Creek should not interact with ground water. <br /> W.... Bishop-Brogden Associates,Inc. <br />