Laserfiche WebLink
• The predicted inflows for the No. 5 is presented in Table 2, Estimated <br />Mine Inflows. The input data is presented on Table 3, Summary of Mine <br />Inflow Input Data - No. 5 Mine. For the longwall portion of the Empire <br />Tract (including Utah Tract extension) the longwall development entries <br />were considered mains. <br />Jacob-Lohman Method. This method assumed that the mine is a large well <br />with constant drawdown and an inflow varying with time. The radius of <br />the "well" was estimated by calculating the radius of a circle with an <br />area equal to the area mined. The average drawdowns for the No. 5 No. <br />Mine was estimated to 400 feet. This equation assumes artesian <br />conditions; however, it has been found to provide a reasonable <br />approximation of mine dewatering inflows where the initial artesian head <br />is large and the radius of the assumed well is large. The equation is <br />as follows: <br />• Q = 2 T sw G(a) <br />a <br />T <br />sw <br />S <br />rw <br />G(a) <br />Tt/S rwz <br />transmissivity <br />drawdown <br />storativity <br />well radius <br />constant drawdown equation <br />This method is most applicable to the N <br />of extensive panelling. At that <br />approximates a large diameter well. <br /> <br />o. 5 Mine inflows after the start <br />time, .the mine most closely <br />-6- <br />