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<br /> <br />The Tow Creek Sandstone lies more than 1300 feet below the Wadge coal. Due to <br />the thickness of the interburden between the Tow Creek and Wadge, it is not <br />likely that hydraulic pressures capable of effecting this aquifer will <br />develop. Therefore, mining activities will not disturb this regional aquifer. <br />About 200 feet below the Wadge coal lies the Trout Creek Sandstone. The <br />Trout Creek is thought to be an aquifer of regional significance, but is not <br />monitored at this site. The applicant is planning on completing a water <br />supply well in the Trout Creek from which they hope to sustain an average <br />pumping rate of 35 gallons per minute. <br />The relatively impermeable interburden between the Wadge coal and the <br />Trout Creek Sandstone (which includes the Wolf Creek coal) and the <br />stratigraphic distance between them will prec]ude impacts to the Trout Creek <br />sandstone from mining, <br />The Wolf Creek coal seam, which lies 150 to 170 feet below the Wadge coal <br />seam, is the first significant aquifer below the mined seam. This seam, which <br />is up to 12 feet thick, appears to be saturated in this area. Due to the dip <br />of the unit and the confining nature of the over and underburden, the <br />Wolf Creek has as much as 770 feet of artesian head in a well. It should be <br />noted that the amount of head is aerially variable as the aquifers conditions <br />change from water table (unconfined) near outcrops to confined conditions at <br />depth. <br />Due to mining methods and the thickness and type of interburden between the <br />Wolf Creek and Wadge, pit inflows from upward movement of the Wolf Creek are <br />not expected. If fracturing of the interburden and/or the Wolf Creek coal, <br />due to blasting or unloading of materials (overburden and Wadge coal seam), <br />were to occur, it is estimated that 80% of the Wolf Creek head would be lost <br />to friction, leaving a maximum total head of about 155 feet, which could <br />potentially result in minor inflow. <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 rec]aimed 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 flaw 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, <br />-32- <br />