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IV. GROUND WATER <br />GROUND WATER ELEVATIONS <br />Water levels in the alluvial wells at the Edna Mine have remained constant over the period of record with minor <br />fluctuations occurting seasonally. Elevations of the water in the alluvial wells and the Wes[ Ridge spoils well are shown in <br />Figure 20. In reviewing the data, it is apparent that the spoils well (WR-I) has reached steady state and exhibits consistent <br />seasonal fluctuations. The seasonal fluctuations result from spring snowmel[ causing a mounding of water in the perched <br />aquifer which drains over the summer via discharge from a spring on [he lower portion of West Ridge near the elevation of <br />Trout Creek. <br />Monitoring Well TR-4 was broken off and plugged by livestock in July 2002, preventing monitoring for the <br />remainder of 2002. The well is scheduled for repair in the Spring of 2003. <br />GROUND WATER QUALITY <br />Comparisons of water quality data gathered from the alluvial wells at the Edna Mine must be exercised with caution <br />due to the differing stratigraphic units intersected along Trout Creek adjacent to [he various wells. The alluvium in the <br />vicinity of Well TR-1.5 intersects stra[igraphy above the Wadge coal seam while the alluvium in [he vicinity of TR-3 <br />intersects stratigraphy below the Wadge seam. Alluvium in [he vicinity of TR-4 intersects even lower stratigraphic units than <br />[hose at TR-3. The influence from contact with the differing lithologies can not be quantified; therefore, differences between <br />the wells may not be responses to mining related activities. <br />Groundwater samples from the October 2002 sampling event for well WR-1 were retested due to results that <br />appeared low for several analytes. Values for TDS, bicarbonate, sulfate, calcium, magnesium, and sodium all appear very <br />low, The lab reanalyzed the samples and verified the original results. WR-1 has demonstrated high variability between the <br />August and the October sampling events in [he past. These results appear [o accentuate [hat pattern. <br />Temperature/pH <br />Temperature (Figure 21) and pN (Figure 22) in 2002 followed the expected trends with temperature exhibiting <br />typical seasonal fluctuations and pH remaining relatively constant over the monitoring period. The amount of temperature <br />fluctuation in Well TR-4 is somewhat greater than expected suggesting the flow to the perched aquifer, although subsurface, <br />is very shallow. <br />27 <br />