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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 2,222,512 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 11 NPDES outfalls. Only one outfall, <br />DP-1, experienced discharge during this monitoring period. All discharges were in <br />compliance with applicable discharge standards. Outfall 026 at the sump dewatering <br />holes has not discharged since the January 1996. The NPDES permit was renewed <br />effective October 1, 2007. <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 of the underground water from the sump <br />dewatering holes or from outfall 004 (Pond PP2). A history of WET testing at Deserado <br />Mine follows below: <br />BME started the whole effluent toxicity (WET) testing program beginning in the fourth <br />quarter of 1989. The mine water effluent was found to be toxic to the test species. <br />Accelerated testing was conducted but the toxicity to the species continued. <br />In a meeting with Colorado Water Quality Control Division (WQCD) staff on January 31, <br />1992, the BME staff reiterated the biomonitoring events, and various measures taken to <br />identify the toxicants and to reduce the toxicity. BME took the following steps to identify <br />potential toxicants. <br />• In the early stages of WET testing, the associated H2S in the effluent was <br />deemed to be a potential toxicant. However, a WET testing done by <br />ENSR Consulting in June 1990 after removing H2S by aeration still <br />10