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TABLE 2.05.6.(3) -1 <br />SUMMARY OF CONSEQUENCES OF THE LIFE -OF -MINE MINING PLAN <br />FOR THE NEW HORIZON MINING AREA <br />Probable Hydrologic Consequences Analysis Results Significance <br />Ground Water <br />1. Interruption of ground water flow and <br />drawdowns <br />PJ <br />0 <br />4. <br />Removal of wells and ponds by mining. <br />Impact of replaced spoil material on ground <br />water flow and recharge capacity. <br />Containment of pit inflow pumpage and <br />impacts on water quality. <br />Maximum projected pit inflow rates will be <br />approximately 5,230 ft3 /day during year 5 of mining at <br />the New Horizon 2 mining area. The maximum extent <br />of the 1 foot drawdown contour is estimated to be 4,000 <br />feet from the center of the pit. <br />No water righted wells are projected to be removed in <br />the remaining areas to be mined except the Garvey Well <br />(water Right 42) and the Ernest Well (Water Right 1). <br />These wells and the land in which they are located, <br />have been bought by the permittee. <br />Horizontal hydraulic conductivities will be higher in the <br />spoil as a result of higher percentages of interconnected <br />porosities. Existing and reclaimed topsoil infiltration <br />rates are similar except for some loss of soil structure in <br />the reclaimed topsoil. Vertical hydraulic conductivities <br />in the overburden are principally limited to <br />interconnected fractures. Flow impeding ledges of <br />consolidated rock are absent in the spoil but there is <br />poorer sorting of grain sizes. <br />Only one exceedence of an NPDES standard has <br />occurred as a result of pond discharges since 1979. Pit <br />pumpage impacts to Calamity Draw and San Miguel <br />water quality are 1.5 percent and .08 percent increases <br />in TDS, respectively. <br />Revised September 2014 JR -64) 2.05.6(3) -18 <br />Short term impact of minimal significance. Any injury to <br />surface water rights will be mitigated according to the <br />surface water augmentation plan. Wells proximate to <br />mining areas are completed in deeper units and are not <br />likely to be injured (little significance). Ground water <br />rights mitigation plan addresses alternative ground or <br />surface water sources should they be needed. No short <br />or long term significant impacts. <br />No impact. <br />Short term impact to topsoil structure but of little <br />significance as far as infiltration rate changes because of <br />plowing and disking practices in the reclamation. Vertical <br />hydraulic conductivities in the spoil will improve because <br />they are no longer dependent on fracture flow. Horizontal <br />hydraulic conductivities should also be higher. <br />There is very little chance of federal or state receiving <br />stream water quality standards being exceeded in any <br />pond discharges. If any problem were to occur, the <br />discharge could be stopped from the pond and the <br />problem could be remediated. Pit pumpage impacts in <br />terms of TDS increases in Calamity Draw and the San <br />Miguel River will be very slight. No short or long term <br />significant impacts <br />