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<br />The streams in the Minnesota Creek basin exhibit water quality characteristics similaz to the North <br />Fork. Iron frequently reaches concentrations in excess of 1.0 mg/L, especially during spring runoff. <br />TDS and TSS levels aze usually low, but exhibit elevated levels during storm runoff or snowmelt. <br />Surface water quality data aze available from three locations in or very neaz the permit area (Map <br />34). Table l7 summarizes the existing data from these locations. As Table 17 shows, there are <br />large variations in concentrations of TDS, TSS, and total iron. High levels of total iron and <br />suspended solids occur during snowmelt or storm flow and aze due to natural sources since no <br />mine-related activities occur in the azea. <br />In order to chazacterize the suspended solids in the streams not currently monitored, WWE and Mr. <br />Pemberton prepazed the sediment transport analysis included in Exhibit 55 and Exhibit SSA. A <br />sediment yield rate of 0.03 acre-feet per square mile per yeaz for the basins was adopted in the <br />permit area. This results in mean annual sediment yield for the permit azea basins being low, <br />ranging from 5 to 50 cubic yazds per yeaz. When coupled with annual water yield, this results in an <br />average annualized sediment concentration of approximately 70 mg/L, which is consistent with <br />regional analyses for the North Fork. <br />Water Quality of Springs <br />The approximate locations of the known springs in the coal lease azea aze shown on Map 37. <br />• Water quality samples from springs in and neaz the permit azea are summarized in Table 20. <br />Spring waters aze typically more saline than the surface waters in the area. TDS levels of the <br />springs range from 78 to 2,400 mg/L, with most of the TDS observations being neaz or above the <br />recommended drinking water standazd of 500 mg/L. Spring water TDS is generally within the <br />TDS range observed for the North Fork, but higher than the TDS range observed for the smaller <br />drainages. <br />Most of the springs located above the F Seam have TDS concentrations neaz or less than 500 <br />milligrams per liter, indicating that the water source is probably local and that there is not a large <br />continuous groundwater reservoir supplying these springs. In general, constituent concentrations <br />in springs below the F-Seam aze higher than those of springs from the Barren Member. <br />Baseline Characterization of Water Quality -North Fork <br />A baseline chazacterization of North Fork water quality was prepazed in to evaluate the potential <br />changes in North Fork water quality that could result from dischazges at the West Elk Mine. The <br />baseline chazacterization was performed downstream of the mine using data from the USGS <br />water quality monitoring station on the North Fork neaz Somerset and from the MCC water <br />quality monitoring station on the North Fork below the old Beaz No. 2 Mine. Data collected after <br />August 1981 for the two stations downstream of the mine facilities is compazed with the baseline <br />in order to evaluate possible impacts of mining and construction activities. <br />Water quality pazameters which were selected for evaluation of changes in this study include: <br />• pH, TSS, TDS, D.O., ammonia/nitrogen, copper, cadmium, total iron, lead, total manganese, <br />nitrate/nitrogen, and chloride. <br />2,04-110 Revised November 2004 PR70 <br />