2009-10-30_PERMIT FILE - C1982056 (8)

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S 1 YEAR .__ 2007 TABLE E51-25 - SIMPLIFIED WATER BALANCE 2008 ... 2009 2010 2011 2012 . 2013 PRODUCTION LEVEL (MMTONS CLEAN) 11.5 10.7 11.7 12.0 J 11.0 9.6 8.4 WATER BALANCE CATEGORY 1 1_ _ t SYStettfintalta (OPintabie,ftlyr) ",,'"'",,-,'," , , - ."-,:;', - '-*I4 4 ,' ,g; U.;,-N:,' , ,... - Mine Inflows' (Southern and Western 110/177.4 110/177.4 110/177.4 110/177.4 110/177.4 110/177.4 110/177.4 Mining Districts) - Mine Inflows' (Eastern Mining District) 65/104.9 65/104.9 65/104.9 65/104.9 65/104.9 65/104.9 65/104.9 - Mine Inflows' (Northern Mining District - 95/153.2 95/153.2 95/153.2 95/153.2 95/153.2 95/153.2 95/153.2 Includes 5MN/6MN Intake Shafts) - Mine Inflows' (North Mains and Portal) 10/16.1 10/16.1 10/16.1 10/16.1 10/16.1 10/16.1 10/16.1 - Potable Water Well 5/8.1 5/8.1 5/8.1 5/8.1 5/8.1 5/8.1 5/8.1 - Operational Use From Pond A '7165 *1165 '1165 *1165 *1165 *1165 *1165 - Supplemental Water (From Off-Site) Negligible Negligible Negligible Negligible Negligible Negligible Negligible Subtotal System Inputs (acre-ft/yr) 625 625 625 625 625 625 625 - Surface Moisture (Coal Shipments) 164.6/265.5 153.2/247.1 167.5/270.2 171.8/277.1 157.5/254.0 137.5/221.8 120.3/194.0 - Mine Ventilation Losses (See Notes) */68.8 '168.8 */68.8 *168.8 */68.8 *168.8 */68.8 - Surface Dust Control 11/17.7 11/17.7 11/17.7 11/17.7 11/17.7 11/17.7 11/17.7 - Washdown Water Pond B 'la 8 '13.8 '13.8 '73.8 '13.8 '13.8 */3.8 Pond C *10.6 */0.6 */0.6 */0.6 *10.6 las *10.6 Pond D '10.5 *10.5 '10.5 */0.5 *10.5 '10.5 '10.5 Pond E */1•9 '11.9 *11.9 *11.9 */1.9 V1.9 */1.9 • - Evaporative Losses (All Active Ponds) '114.0 '114.0 */14.0 */14.0 '114.0 '714.0 '114.0 Subtotal System Outputs (acre-ft/yr) 372.8 354.4 377.5 384.4 361.3 329.1 301.3 Change in Storatle (anre4t/yr) ' r' ' 252.2 ' - 270:6 " -, ''247.5 ' 240:6'7: " ' ' - '205.9'!" ', , :323.7,.' _.. .. - . .- . . Notes: General - Inputs to Twentymile Coal Company's (TCC) water system are primarily ground water inflows to the active mine workings. With the exception of the system outputs identified, all water is recycled and reused within the mine water system. Astensk denotes value not available. 1 - Due to the dip of the coal seam, and the mining method (longwall mining updip), ground water inflow to the active mine workings and mined-out areas is generally intercepted by the active workings (current active panel and development workings) and remains relatively constant 2 - TCC occassionally has supplemental water trucked-in from off-site to meet specific operational needs. This does not occur frequently and the quantities are not significant • 3 - Surface moisture loss calculation based on 2/3 of production passing through washplant, with output of 3.7 percent surface moisture, and remaining 1/3 of production at surface moisture of 2.0 percent - Moisture loss occurs through mine ventilation due to an increase in relative humidity as ventilation air passes through the mine. Given, however, that the increase in relative humidity is due to evaporation of ground water within the mine, the moisture loss does not represent a surface water depletion. 5 - Based on maximum (total) pond surface area of approximately 40.9 acres and average annual evaporation rates from NOAA evaporation maps 6 - Given that at system inputs are recycled, with the exception of the identified system outputs (losses or depletions), the difference between inputs and outputs represents a net change in system storage. Water is currently (2007) stored underground in the Southern and Eastern Mining Districts (capacity about 2,540 acre-ft), and above-ground in either or both of the two million-gallon storage tanks and in the Area 1 Pit. In the future, the Eastern Mining District will be dewatered, and this water along with incremental storage from ongoing operations wit be stored in the southern portion of the Western Mining District (capacity about 1,410 acre-ft). - . • TR07-59 Table E51-25 04/02/07