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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 completed a water supply well in the Trout <br />Creek from which they sustain an average 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 stratigraphic <br />distance between them will preclude impacts to the Trout Creek sandstone from <br />mining. <br />The Wolf Creek coal seam, which lies 150 to 170 feet below the Wadge coal seam, <br />is the first significant aquifer below the mined seam. This seam, which is up to 12 <br />feet thick, appears to be saturated in this area. Due to the dip of the unit and the <br />confining nature of the over and underburden, the Wolf Creek has as much as 770 <br />feet of artesian head in a well. It should be noted that the amount of head is aerially <br />variable as the aquifer conditions change from water table (unconfined) near <br />outcrops to confined conditions at depth. <br />Due to mining methods and the thickness and type of interburden between the Wolf <br />Creek and Wadge, pit inflows from upward movement of the Wolf Creek are not <br />expected. If fracturing of the interburden and /or the Wolf Creek coal, due to <br />blasting or unloading of materials (overburden and Wadge coal seam), were to <br />occur, it is estimated that 80% of the Wolf Creek head would be lost to friction, <br />leaving a maximum total head of about 155 feet, which could potentially result in <br />minor inflow. <br />The aquifer characteristics of the Wolf Creek (low transmissivity and storativity <br />values) indicate that very little water is available for upward movement. Due to the <br />distance between the Wadge and Wolf Creek, fracturing of the Wolf Creek due to <br />mining is improbable. Inflow from the Wolf Creek coal seam into the open or <br />reclaimed pits is not expected to occur. <br />The Wadge coal and its overburden, which may locally contain the Lennox coal <br />seam, generally stores and transmits water. During mining, water is induced to <br />flow into active and reclaimed pits. This water flows mainly from the Wadge coal, <br />but also from the overburden. The operator estimated the following values for <br />aquifer characteristics in the Wadge Coal and Wadge Overburden: <br />* Hydraulic conductivity of overburden = .01 ft. /day <br />* Hydraulic conductivity of coal = 0.02 ft. /day (north pit), .01 ft. day (south pit) <br />* Storativity = 10-2 for both aquifers <br />* Transmissivity = 4.5 ft. 2 /day for overburden <br />* Transmissivity = 0.12 ft. 2 /day for coal <br />* Hydraulic gradient of overburden = .165 (north pit), .085 (south pit) <br />* Hydraulic gradient of coal = .15 (north pit), .11 (south pit) <br />Seneca II -W Findings Document 36 C- 1982 -057 <br />Permit Revision No. 6 January 6, 2012 <br />