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EFCI Southfield Mine -Year 2007 Annua/Hydrology Report April 2l, 2008 <br />2.0 GROUND WATER INFLOWS, USE AND DISCHARGE <br />2.1 Mine Inflows <br />Although still included as a monitoring and reporting requirement in Exhibit 25, mine inflow <br />monitoring was discontinued after September 2001 because access to monitoring sites was <br />eliminated when the mine portals were sealed in December 2001. Mine inflows for 2001, as the <br />last reporting period, were estimated at 5.2 acre-feet as compazed to 10.3 acre-feet during the <br />previous reporting period. Prior to 2002, mine inflow locations were monitored semi-annually <br />during the spring and fall for each annual reporting period. The 2001 mine inflows represented a <br />decrease from prior years possibly due to continuing drought conditions at that time along with the <br />elimination of former inflow or seep locations due to retreat mining Review of historic mine <br />inflow water quality monitoring results from previous Annual Hydrology Reports indicates little <br />variance in inflow water quality over time. <br />2 2 Mine Water Handlin~Use, Consumption and Discharge <br />During active operations, water-handling systems in the mine captured most mine water inflows <br />near their source. Within the mine, captured mine water was pumped downhill to either the <br />abandoned 1st North Mains or to the mined-out and abandoned west area of the mine. Prior to <br />sealing of the mine, mine water handling activities were discontinued. Mine inflows will continue <br />within the sealed mine workings and water will accumulate, initially in the lowest portions of the <br />mine-out workings and gradually rising into other mined-out areas until a dynamic equilibrium is <br />reached between mine water inflows and discharge to ground water systems. <br />During the reporting period, consumptive water use was limited to minor pond evaporation. Use <br />of the Corley Well as a water source was discontinued in late January 2001. Due to drought <br />conditions over the past few yeazs, the only ponds that have held any significant quantities of <br />water were Ponds 4 and 5 at the Mine Site. These ponds held water from storm events <br />intermittently during the spring, summer, and early fall before drying out. The 2007 pond <br />evaporation is estimated at 0.64 acre-feet similaz to previous yeazs. The source of water for any <br />minor consumptive uses typically is trucked to the site from Florence or Rockvale. No water was <br />trucked to the site during 2007 and it is anticipated that future consumptive water use will be <br />limited to pond evaporation from the remaining sedimentation ponds (Ponds 4, 5, L1, and L2). <br />Total consumptive use for 2007 is therefore estimated at 0.64 acre-feet, as indicated on Table 1, <br />Water Balance and Consumptive Use Summary. <br />The water balance compares water source withdrawals (consumptive use) with discharge <br />quantities. Withdrawals previously included any excess mine water pumped from the mine as well <br />as water withdrawn from wells. No water was pumped from the mine or withdrawn from on-site <br />wells during 2007. Consumptive use during the reporting period was limited to only pond <br />evaporation. No pond water was discharged to area streams in 2007. The absence of discharges <br />was due to the combination of infrequent storm events and the reduced volume of runoff from <br />storm events as a result of increased vegetation establishment on reclaimed areas. Previous pond <br />discharges were typically within NPDES permit limitations as documented in prior Annual <br />Hydrology Reports . <br />2007 AHR.doc WP Page 4 <br />