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Page 2 of 3 <br />The temporary increase predicted in the PHC section of the Deserado Mine permit would have <br />most likely occurred during construction of the facilities area. Although the prediction no longer <br />applies, the effect of sedimentation ponds on the site is to reduce TSS to levels lower than they <br />would be during a storm event. Discharge Monitoring Reports during the 2012 water year showed <br />that only Outfall 001 discharged during the water year and showed consistently low suspended <br />solids. <br />4. PHC: Mine inflows are predicted no to exceed 5 to 10 gpm. <br />Incidental leakage into the mine site includes leakage from pipe leaks, road watering, and wash - <br />down water. The 2012 AHR lists 6.55 gpm mine inflow from the incidental water. <br />5. PHC: Very little water will be pumped to the surface from the underground mine. <br />A new dewatering system was installed in May 2012 to pump excess water captured underground <br />to the surface for treatment and discharge. The water pump rate from the mine workings during <br />the 2012 water year starting in May was estimated at 5,241,600 gallons or 9.97 gpm. <br />6. PHC: The local groundwater table may be lowered as mining proceeds. <br />The 2012 AHR shows a decline in piezometric level in wells in close proximity to mine <br />workings. Five monitoring wells have turned dry as a result of being mined through. Five <br />monitoring wells showed a rise in water levels from the 2011 -2012 water year and four wells <br />showed a decrease in the water table. Well 33 -8U was obstructed by a dead rodent at 211.9 feet. <br />Historically, the changes in water level for 33 -81J closely mimics those of 33 -8M and 33 -8L. <br />7. PHC: The effects of subsidence in the Red Wash and in Scullion Gulch will be short- lived. <br />As projected, subsidence in the Red Wash initially resulted in water ponding in the stream <br />bottom. High content of silt and clay carried by the Red Wash have sealed any cracks that formed <br />in the alluvium and has maintains its original channel. Subsidence in the Scullion Gulch resulted <br />in no surface hydrologic consequences observed to date. <br />8. Refuse disposal effects on surface and groundwater system is expected to be minimal. <br />The 2012 AHR included no data on this prediction. There was no discharge on surface water <br />from ponds RP -1, PR -2/3/4 and RP -5 treating run -off from the waste piles. Seeps and springs are <br />absent in the refuse disposal area and the entire site receives low precipitation. Overall, the refuse <br />disposal area contributes only small amount of water to the surface and underground hydrologic <br />system. <br />The 2011 -2012 point of compliance was monitoring well 22 -3M. Field parameters measured were pH and <br />conductivity. Samples were analyzed for dissolved iron, manganese and total dissolved solids. <br />