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r <br /> o Transit Mix Concrete Co. <br /> Response: The North Pit Extension has been revised so that the pit floor is at least <br /> 10 feet above the elevation of Deadman Creek. Deadman Creek is an ephemeral <br /> creek, and this suggests that the water table is below this elevation. Several <br /> boreholes were drilled in this area,and no significant sources of water were <br /> identified. Drilling mud was continuously lost with no fluid return while drilling in <br /> this area. This suggests that seepage,if encountered,will be limited. Runoff from <br /> impacted areas will be routed through detention basins,which will reduce peak <br /> flows from these areas. Therefore,flows in Deadman Creek are not expected to be <br /> impacted. A more detailed discussion of the hydrologic balance along Deadman <br /> Creek has been included in Exhibit G. <br /> Geology/Hydrogeology/Hydrology <br /> 160) Comment: The text states that Little Turkey Creek flows most of the year in the granitic <br /> canyon portions of the property in Section 16,but does not flow year-round in the lower <br /> alluvial material areas of the property in Sections 15 and 22. Please submit a <br /> diagrammatic cross-section oriented roughly perpendicular to the east fault zone, which <br /> depicts the hydrogeological setting of the area from the proposed mining area to the area <br /> east of the fault zone.Additional cross-sections and/or diagrams may be needed to fully <br /> describe the hydrogeological setting,including the relationship of the creek fault zone <br /> aquifers with the east fault zone and the sandstone aquifer located east of the fault zone. <br /> Response: This cross section will be included in Exhibit C. <br /> 161) Comment: The text states that the north-south oriented high-angle thrust faults probably <br /> functions as a barrier to groundwater flow, effectively isolating the groundwater system <br /> in the hard rock materials from the sedimentary formations. Please provide additional <br /> information to support this statement. While the fault zone may act somewhat as a <br /> hydrologic barrier,one would expect some groundwater flow to occur through this <br /> structural feature,perhaps not at a consistent rate. However,the question of whether or <br /> not the fault zone acts as a hydrologic barrier is not as critical given the Division's <br /> requirement for the operation to develop and implement a groundwater monitoring <br /> program. Under this program, existing groundwater conditions will be characterized <br /> before mining begins, and groundwater will be regularly monitored for impact. <br /> Response: Faulting between the granite and sedimentary rock may act as a conduit <br /> for flow parallel to the fault through brecciated areas, but the fault typically <br /> restricts flow perpendicular to the faulting.Bishop-Brogden Associates includes a <br /> detailed discussion,with references cited,of groundwater flows in the vicinity of the <br /> faults in their response to comments memorandum included in Exhibit G. <br /> 162) Comment: The text indicates that the Little Turkey Creek and Deadman Creek <br /> drainages are both structurally controlled by narrow fault zones trending northwest to <br /> southeast along the creeks,but not extending beyond the drainages as presented in Figure <br /> C-3. However, in looking at Figure C-3,a portion of the Deadman Creek fault zone <br /> Hitch Rack Ranch Quarry(M-2016-010) <br /> Response to Comments—July 14, 2016 <br />