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Second Alkali Creek is an ephemeral drainage that crosses the northern end of <br />permit area. Since there will be no surface disturbance in this area other than <br />possible subsidence, the mine is not expected to affect Second Alkali Creek. <br />Stipulation 15 was added to the permit to incorporate sampling of Second Alkali <br />Creek into the permit. <br />Requirements to monitor Magpie and Second Alkali Creeks, as addressed in <br />Stipulations 14 and 15, have been added to Exhibit 25 of the permit application. <br />All data will be reported in the Annual Hydrology Report. <br />Oak Creek, a perennial stream, flows near the loadout. In accordance with Rule <br />4.24.4, the operator has conducted quarterly upstream and downstream <br />monitoring of this creek and continues to do so. There have been no apparent <br />impacts on Oak Creek from the operation of the loadout. Any surface water <br />drainage from the disturbed area passes through a sediment pond and must <br />meet NPDES effluent limits. There has never been a recorded discharge from <br />either of the loadout ponds. As a result, no impacts to Oak Creek are <br />anticipated. <br />Baseline surface water quality in the permit and adjacent areas reflects the <br />effects of previous coal mining activities. Surface water in the mine and loadout <br />areas can be characterized as calcium-carbonate and sodium sulfate types, <br />respectively. Surface water baseline monitoring data provided by the operator <br />shows high levels of both TSS and TDS and elevated concentrations of iron. <br />Water samples collected from Newlin Creek in 1983-84 had TSS levels of 4-16 <br />mg/I and TDS levels of 110-165 mg/I. Iron levels of these samples ranged from <br />0.1 to 3.64 mg/l. Current beneficial use of surface water in both the mine area <br />and loadout area is limited by upstream diversions. Newlin Creek is diverted by <br />the City of Florence upstream from the mine. Oak Creek is utilized as a primary <br />municipal water source for the town of Rockvale five miles upstream from the <br />loadout area. Therefore, impacts of the mine on beneficial use of water are <br />considered negligible. The only significant change in the surface hydrologic <br />balance after 1980 was an increase in mine water discharge. Most of the mine <br />inflow was derived from the 1 st North Sump area from fractures and connections <br />to overlying abandoned mine workings. The total amount of mine inflow has <br />ranged from as high as 72 acre feet to as low as 9.8 acre feet per year. The <br />total mine water discharge to Magpie Creek has ranged from a high of 26.7 acre <br />feet in 1987 to a low of 0 acre feet in 2000. Since all mine water is discharged <br />through an NPDES approved discharge point, all effluent limitations are met <br />before discharge. Therefore, the impact to the natural drainage has been <br />considered to be negligible. <br />Cumulative Hydrologic Impact Statement <br />A Cumulative Hydrologic Impact Statement (CHIS) was completed for the <br />Southfield Mine and considered the hydrologic impacts of all anticipated mining <br />Page 27 of 36