REP40746 - Laserfiche WebLink

Home Browse Search

xv. Ground Water LI Water levels in the alluvial wells at the Edna Mine have remained constant over the previous years with minor fluctuations occurring seasonally. Elevations of the water in the alluvial wells and the spoils well are shown in ' Figure 9. As suggested in the baseline studies, the occurrence of a drawdown in any of the wells is anticipated only during mining at the base of the slope ' near Trout Creek. In reviewing the data, it is interesting to note that the spoils well has also reached steady state. The equilibrium of WR-1 is further evidenced through the surface expression of a spring on the lower portion of West Ridge near the elevation of Trout Creek. G ound Wa Opal; v Comparisons of water quality data gathered from the alluvial wells at the Edna Mine must be exercised with caution due to the differing stratigraphic units intersected along Trout Creek adjacent to the various wells. The alluvium in the vicinity of Well TR-1.5 intersects stratigraphy above the Wadge coal seam while the alluvium in the vicinity of TR-3 intersects stratigraphy below the Wadge seam. Alluvium in the vicinity of TR-4 intersects even lower stratigraphic units than those at TR-3. The influence from contact with the differing lithologies is not able to be quantified, therefore, differences ' between the wells may not be responses to mining related activities. The general characteristics: temperature (Figure 9) and pH (Figure 10) show the expected trends with temperature exhibiting typical seasonal fluctuations and pH remaining constant over the monitoring period. ' Specific conductivity (Figure 10) values for the three alluvial wells have remained fairly constant over the period of record and consistent with values obtained during the baseline studies. As previously discussed, the October 1990 and August-October 1991 specific conductivity values may be suspect due to two separate malfunctions of the Horiba testing equipment. Conductivity values during 1989, 1990 and 1991 for the spoils well WR-1 begin with elevated levels caused by the leaching of various elements continuing i