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<br />The aquifer characteristics of the Wolf Creek (low transmissivity and <br />storativity values) indicate that very little water is available for upward <br />movement. Due to the distance between the Wadge and Wolf Creek, fracturing of <br />the Wolf Creek due to mining is improbable. Inflow from the Wolf Creek coal <br />seam into the open or reclaimed pits will not occur. <br />The Wadge coal and its overburden, which may locally contain the Lennox coal <br />seam, generally stores and transmits water. <br />While mining, water will be induced to flow into active and reclaimed pits. <br />This water will flow mainly from the Wadge coal, but also from the overburden. <br />The amount of inflow to each successive pit will vary according to the <br />location of the pit in relation to postulated flow paths. The applicant <br />estimates that a worst case inflow into a 120 feet long by 120 feet wide pit <br />will be 57.2 gallons per day (0.04 gallons per hour). This low inflow <br />estimate is based primarily on a low transmissivity value calculated at a <br />Wadge coal test hole. The calculated transmissivity value is 0.03 FT2/Day <br />(0.224 gallons per day per feet2). Using this value, it is estimated by the <br />applicant that ground water effects will not be observed more than 500 feet <br />away from mining. The Division assumes that the transmissivity is actually <br />somewhat greater than that calculated at the well, but is probably variable. <br />The Division projects that inflows in excess of 57.2 gallons per day will be <br />measured at each pit, and that the effects of mining on the local ground water <br />regime will be felt farther away than 500 feet from the pits. This assumption <br />is based upon transmissivity and storativity values of the ~4esaverde Formation <br />throughout Western Colorado. <br />As a general rule, transmissivity and storativity values of the middle to <br />upper Mesaverde, as reported by various mines in western Colorado, are low. <br />However, a value as low as that reported from the Seneca II-W site has not <br />been documented elsewhere. The values calculated at the particular aquifer <br />test site are probably good for that test site, however, the Division must <br />assume that these aquifer characteristics are aereally variable. Therefore, <br />the actual storativity and transmissivity values for the Wadge coal as a unit <br />are probably greater then those reported. <br />The Division's PHC findings are based on greater inflows than those predicted <br />by the applicant <br />The Williams Fork Formation overburden which locally contains the Lennox Coal <br />Seam, may contain perched aquifers as well as acting as a limited aquifer <br />system near the Wadge coal. The overburden does not contain or transport <br />significant amounts of water in this area. <br />-35- <br />