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• gradient in each coal seam and the combined <br />transmissivity of each coal seam and the sandstone <br />overburden were multiplied following Darcy's Law to <br />obtain a unit flow through the combined coal and <br />sandstone (Table B). The unit flow through each <br />coal and its fractured overburden sandstone was <br />multiplied by the maximum length of the area <br />through which it would flow to get the calculated <br />ground water inflow (Table D). The length of the <br />area through which it would flow was calculated by <br />adding the distance to the hydrologic divide to <br />twice the length of the mine face at the greatest <br />depth of penetration, as indicated in footnote (e) <br />of Table D and in Table E. <br />In response to the request for records of ground <br />• water inflow measurements from areas already mined, <br />the following exhibits and tables are included. All <br />measurements of mine water inflow were begun after <br />June, 1980. Prior to the initial application, <br />observations of mine rater inflow were limited to <br />those reported on page G-79. All measurements of <br />ground water inflow into these working mines are in <br />the form of a mass balance where the water removed <br />from the mine, plus the water stored in the mine, <br />less any water brought into the mine is assumed to <br />be the water flowing into the mine through the coal <br />seam. <br />The measured rate of water pumpage from Northern <br />No. 1 mine (FF coal seam) is shown graphically in <br />Exhibit B. Pumping of water out of the mine did not <br />begin until August, 1980. Water has been imported <br />• into the mine since mining began, but no records <br />Leonard Rice Consultwg Water Fngirreers.lnc. <br />