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section which had originally produced water was sealed in 1990. Further dewatering <br />of the mine from areas which previously produced water is not projected to be <br />necessary until water in the originally sealed area backs up to the seals, and is <br />drained to a dewatering sump to be used in the mining process. At the 1990 inflow <br />rate, this would not occur for approximately 60 years. <br />The source of inflows to date is believed to be a mix of water infiltrating the graben <br />along the faults and water in the coal seam. The mine was largely idle between 1992 <br />and 1999; operations resumed in early 2000. As projected, additional mine inflows <br />have been encountered since operations resumed, as the workings have extended <br />further to the east into the predicted saturated portion of the Cameo seam. In April <br />2000, seepage was observed in the mining faces developing to the east. Current <br />estimated inflow rate as documented in the 2005 Annual Hydrologic Report (AHR) <br />is approximately 31.4 gpm, which is in line with PHC projections indicated in <br />Appendix N of the application (30 gpm inflow predicted for 0.5 million ton per year <br />production rate. This does not include the inflows into sealed portions of the mine <br />north of the East Mains discussed in the previous paragraph. The inflow water is <br />collected in mine sumps and used for dust control in the mining process and for haul <br />road dust control. Initially following resumption of operations in 2000, inflows were <br />entirely consumed by dust control operations, but beginning in May 2002, discharge <br />via CDPS Outfall 002 was resumed. For the purposes of projecting the effect mine <br />discharge will have on East Salt Creek, PHC projections in Appendix N have <br />assumed a conservative maximum mine flow rate of 100 gpm, or 0.22 CFS. <br />The quantity of inflows which have been observed to date and are projected upon <br />resumption of mining in future permit terms are considered to be insignificant with <br />respect to effects on flow in the ephemeral surface drainages, or with respect to <br />recharge of the coal seam. Based on information provided in the permit application, <br />ground water intercepted by the mine does not appear to be in communication with <br />any aquifers being put to beneficial use, and there are no registered wells within two <br />miles of the permit boundary. <br />The quality of water discharged from the mine is similar or higher quality than water <br />in East Salt Creek at the confluence with McClane Creek, and any discharge is <br />required to meet NPDES discharge standards. For these reasons, no detrimental <br />impact to ground water resources or to surface water quality downstream of the <br />permit area is expected. Original ground water flow patterns in the mined area will <br />ultimately be reestablished after the mine is sealed and the abandoned workings <br />slowly fill with water. <br />An alluvial aquifer has been identified along East Salt Creek. Monitoring wells <br />established in the alluvium indicate that alluvial water levels fluctuate seasonally in <br />response to flow in East Salt Creek. Data collected by the applicant from the Salt <br />Creek alluvial aquifer indicate a carbonate-sulfate type water, similar to the <br />characteristics of the surface water in the system as would be expected. No effects to <br />alluvial ground water quality or quantity are anticipated. <br />20