2012-01-30_REPORT - C1981018 (2)

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Hydrology Report (January 1998). Water quality data for 32 -7M was collected in 2001 prior to mining it out and is included in Appendix C of the Seventeenth Annual Hydrology Report (January 2002). Comparing the 2001 data to the 1997 data indicated only slight changes with a general improvement in quality for most parameters of 32 -7M. Water quality data for 30 -8M was collected in December of 2006 prior to longwall mining of adjacent areas. Comparing the 2006 data to the 1997 data indicates a general improvement in water quality. 2.2.1.5 Mine Water Balance Table 2 -2 shows the water balance for the Deserado Mine. No water has been pumped from underground workings since January 10, 1996. During the 1996 -1997 period, Deserado Mine started disposing the prep plant thickener water in the mined out area of the D -Seam (the first longwall district). This water would have been otherwise discharged through Pond PP -2. Ingoinq Water The production equipment utilizes water for dust control and cuttings removal in roof bolting. Water used by equipment is based on 580 shifts worked by continuous miner sections and 267 shifts worked by the longwall. The continuous miner sections use 100 gpm and operate about 4 hours per shift (the rest of the time is spent moving, etc.). The longwall equipment uses 200 gpm of water for about 8 hours per shift. The amount of water entering the mine as ventilation intake air humidity is based on monthly mean temperatures from Table II.0 -1 on page II.0 -5 of the Mining Permit and the yearly mean relative humidity of 56% found on page II.E -1 of the Mining Permit. The absolute humidity, the actual amount of water in the air, is calculated from these data using an average ventilation quantity of 408,438 cubic feet per minute. 8