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The smallest quantity of water entering the mine is the incidental category. This category <br />includes leakage from water lines, dust control watering in the haulage entries, and <br />washdown water used in the slope and other locations. It has been assumed that 10% of <br />the water used for production equipment will fall under this category. <br />Outgoing Water As coal is mined, water is added by dust control sprays on the <br />continuous miners, the longwall shearer and at transfer points along the conveyor belt <br />system. This water is then carried out of the mine as surface moisture on the raw coal. <br />This added coal surface moisture represents a 4% increase in the raw coal moisture <br />content. The raw coal tonnage produced during this reporting period was 2,325,516 tons. <br />Water leaving the mine as ventilation humidity represents a large quantity in the water <br />balance. The temperature of the exhaust ventilation air is almost constant, at 60° F. <br />Up until the commissioning of the new mine dewatering system in May 2012, no <br />underground water had been pumped out since January 1996. Water encountered in the <br />active areas of the mine was pumped to the mined out D seam area for storage. <br />In May 2012 a new dewatering system was commissioned to pump excess mine water to <br />the surface for treatment, storage, and potentially discharge. An average of 25.46 gpm <br />was pumped to the surface. No discharge of the dewatering waters through the <br />associated NPDES outfall occurred during the water year as most of the water was <br />allowed in infiltrate through multiple ponds. <br />2.2.1.6 NPDES Discharges At present, BME has 12 NPDES outfalls. Outfall 001 last <br />discharged during the 2011 -12 water year. This discharge was in compliance with <br />applicable discharge standards. Outfall 026 at the sump dewatering holes has not <br />discharged since the January 1996. Outfall 029 was added to the permit to allow for <br />pumping, treatment and discharge of B -seam water from the mine workings to the <br />surface. The facilities associated with this system were constructed and commissioned in <br />May of 2012. No discharge has occurred through Outfall 029 to date. <br />No discharges through external outfalls occurred during the water year. <br />The NPDES permit was renewed effective October 1, 2007. A renewal application was <br />timely submitted in March of 2012. The CDPHE has not updated this permit to date and <br />we continue to operate per the amended permit received when Outfall 029 was added. <br />2.2.1.7 Whole Effluent Toxicity (WET) Testing No WET testing was conducted during <br />the water year since there was no discharge through any outfall carrying this requirement. <br />A history of WET testing at Deserado Mine follows below: <br />10 <br />