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Since the alluvial aquifer and the stream are hydraulically connected, the effects <br />observed in the aquifer should be apparent in the stream. The effects that have been <br />observed in the alluvium and the stream would be represented by the data from the up <br />and down gradient monitor points. Data from surface monitoring stations S-1 and S-2, <br />and wells W-7 and W-5 should therefore represent the effects the activity from 1985 <br />(the end of mining activities) until the end of the monitoring period. <br />Data from the wells W-7 (located up gradient) and W-5 (located down gradient) from <br />the September 1989 sampling event were compared to determine impacts to the <br />shallow alluvial aquifer. The comparison of these two results indicates the water quality <br />actually improves in the down gradient well. This data indicates that the alluvial aquifer <br />has exhibited relatively little impact, if any. <br />An exception is noted that the quality in the well A-1, located west of the former east <br />pit area, has shown, since December 1994, elevated levels of TDS, conductivity, <br />sodium, magnesium, manganese, iron, calcium, and sulfate. Compared [o other wells <br />in the area this well has traditionally demonstrated elevated levels of these constituents. <br />This well is continuing to be monitored as part of the current monitoring program. <br />Wells A-I, W-1 and W-5 have had lineaz regression analyses performed to attempt to <br />predict future electroconductiviry and total dissolved solids (TDS) levels in the water <br />samples from the wells. The analysis indicates that in all three wells, <br />electroconductivity will continue to rise, and in W-I and W-5, the TDS levels will <br />continue to rise but be within the recommended agricultural levels. <br />A conservative estimate of salinity from backfilled spoils discharge loading on <br />Stollsteimer Creek was developed based on a recharge model. Average precipitation <br />at the site is 13.41 inches/year (1.1175 feet/year). All discharge from the pits will be <br />based on infiltration from precipitation. The area of the East Pit is approximately 46 <br />acres. The area of Barren Ridge is approximately 39 acres, for a total area of 85 acres. <br />Assuming that 25% of precipitation infiltrates, the backfilled pits will discharge 23.75 <br />acre-feet per year or 90 gpm (0.2 cfs) over a two month period. <br />The flow data on Stollsteimer Creek is limited to data collected by Kaiser. The lowest <br />flow recorded occurred in June 1989, at Station S-1 and was 1.78 cfs. The TDS was <br />557 mg/l. Kaiser has run a regression analysis on total dissolved solids in spoils well, <br />W-16 in the East Pit which projects a maximum spoils total dissolved solids <br />concentration of 1294 mg/I in the year 2004. A weighted salinity loading between the <br />low flow and the projected spoils discharge yields a total dissolved solids concentration <br />of 631 mg/ l . <br />This concentration would not pose a limitation to downstream users. <br />Ground Wnter Impacts <br />Pictured Cliff Sandstone: The Pictured Cliffs is separated from coal seam "C" by <br />approximately 35 feet. Between the fill material and the sandstone is a shale, sandstone, <br />12 <br />