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Ingoing Water The production equipment utilizes water for dust control and cuttings <br />removal in roof bolting. Water used by equipment is based on 465 shifts worked by <br />' continuous miner sections and 248 shifts worked by the longwall. The continuous miner <br />sections use 100 gpm and operate about 3 hours per shift (the rest of the time is spent <br />moving, etc.). The longwall equipment uses 150 gpm of water for about 7 hours per shift. <br />The amount of water entering the mine as ventilation intake air humidity is based on <br />monthly mean temperatures from Table II.C-1 on page II.C-5 of the Mining Permit and the <br />yearly mean relative humidity of 56% found on page II.E-1 of the Mining Permit. The <br />absolute humidity, the actual amount of water in the air, is calculated from these data <br />using an average ventilation quantity of 469,237 cubic feet per minute. <br />Thickener water transferred underground for storage was estimated at 6,400,000 gallons <br />' during the reporting period. This number is based on operational knowledge of the tons <br />washed and other factors such as the type of clays encountered, processing equipment <br />efficiencies, etc. <br />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 be used 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 2,580,512 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 />No underground water has been pumped out since January 1996. Water encountered in <br />the active areas of the mine is pumped to the mined out D seam area for storage. <br />Currently only 14 gpm is pumped on average. About one half of this is from pipe leaks, <br />wash down, etc. The remainder is from groundwater encountered during the course of <br />mining. <br />2.2.1.6 NPDES Discharges At present, BME has 15 NPDES outtalls. Only one outtall, <br />DP-1, experienced discharge during this monitoring period. All discharges were in <br />9 <br />