Laserfiche WebLink
<br />To present the worst-case conditions, it was assumed that a panel typical <br />of this shown in the mine plan was opened at the extreme northern edge <br />of the property. If such a panel extended the width of the proposed mine <br />(about 1000 feet), it would be about 150 feet wide and would encounter <br />134 feet of saturation. This opening would have an effective wetted area <br />of 1.50 x 105 ftw, and would be rectangular. It was assumed that if <br />the opening were a circular well, its radius would be about 220 feet. <br />Exhibit 26 combines the radius of influence from the left half of the <br />figure and the effective radius of the panel. The potential maximum <br />steady-state inflow has been calculated at about 21 gpm. The maximum <br />specific capacity of an aquifer can be achieved when drawdown is about <br />70% of the saturated thickness (Johnson 1966). In this case, drawdown <br />would be about 90 feet. This would occur in about 20 days after the <br />panel was opened, and the resulting maximum expected flow would be <br />about 70 gpm. The flow would eventually decline with declining water <br />levels and stabilize at about 20 gpm. <br />Although many assumptions have gone into the calculations, the aquifer's <br />ability to transmit water is so small that the resulting figures of <br />inflow and radius of influence are intuitively reasonable. Based upon <br />the preceding discussions and calculations, mine water inflow should <br />not be considered a serious environmental or engineering limitation. <br />4.2 RESULTS AND DISCUSSION OF M-K'S SUPPLEMENTAL GROUNDWATER STUDY <br />CONDUCTED IN 1980 <br />4.2.1 Supplemental Data Requirements <br />The need for additional subsurface hydrologic regime information became <br />inherent upon a thorough review of the new proposed Colorado Mined <br />Land Reclamation Board regulations. The previous VTN study lacked the <br />density of wells required to address. various regulatory requirements such <br />as potentiometric surface maps and seasonal variation. Upon assessment <br /> <br />21 <br />