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' 4utaoina Water As coal is mined, water is added by dust control sprays on the continuous <br />miners, the longwall shearer and at transfer points along the conveyor belt system. This <br />water is then carried out of the mine as surface moisture on the raw coal. This added coal <br />' surface moisture represents a 4% increase in the raw coal moisture content. The raw coal <br />tonnage produced during this reporting period was 2,581,408 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 the fire episode. Water encountered in <br />the active areas of the mine is pumped to the mined out D seam area for storage. Currently <br />only about 8 gpm is pumped on average. <br />2.2.1.6 NPDES Discharges At present, BME has 15 NPDES outfalls. Only three outfalls <br />' (DP1, SS-1 and RP-2/3) experienced discharge during this monitoring period. RP-2/3's <br />discharge was due to a faulty riser pipe. All discharges were in compliance with applicable <br />discharge standards. Outfalls 024 and 026 at the sump dewatering holes have not <br />discharged since the January 31, 1996 underground fire episode. All discharges were within <br />the permit requirement. <br />2.2.1.7 Whole Effluent Toxicity (WET) Testing No WET testing was conducted during the <br />water year since there was no discharge of the underground water from the sump dewatering <br />' holes or from outfall 004 (Pond PP2). A history of WET testing at Deserado Mine follows <br />below: <br />' BME started the whole effluent toxicity (WET) testing program beginning in the fourth quarter <br />of 1989. The mine water effluent was found to be toxic to the test species. Accelerated <br />~ testing was conducted but the tobcity to the species continued. <br />In a meeting with Colorado Water Quality Control Division (WQCD) staff on January 31, 1992, <br />the BME staff reiterated the biomonitoring events, and various measures taken to identify the <br />toxicants and to reduce the toxicity. BME took the following steps to identify potential <br />toxicants. <br />In the early stages of WET testing, the associated HZS in the effluent was <br />deemed to be a potential toxicant. However, a WET testing done by ENSR <br />Consulting in June 1990 after removing HzS by aeration still showed toxicity. <br />This result indicated that some other factor(s) also contributed to the toxicity. <br />9 <br />