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Table 9 -Comparison of observed EC values to material damage suspect EC <br />values during October through January in Stollsteimer Creek and in <br />AVF monitoring well W-5 <br /> Material <br />damage Observed <br />baseline mean <br />Observed post- <br /> suspect 1980-1 mining mean, 1985 <br /> level - 2002 <br />Surface water in <br />Stollsteimer Creek <br />(baseline site S-1, 700 942 (n=3) 801 (n=15) <br />post-mining site S-2) <br />(electroconductivity <br />in micromhos/cm) <br />Alluvial water well <br />W-5 on AVF 1,050 993 (n=3) 972 (n=10) <br />(electroconductivity <br />in micromhos/cm) <br />This comparison indicates the Chimney Rock Mine has not caused material damage to the waters of <br />the Stollsteimer Creek AVF, and the essential hydrologic functions have been preserved by <br />maintaining the geologic, hydrologic, and biologic chazacteristics that support those functions. <br />Findines on Protection of Hydrolo¢ic Balance <br />All hydrologic structures have been reclaimed and any water pollution that is occurring is unlikely to <br />cause material damage. The Probable Hydrologic Consequences section ofthe Chimney Rock Mine <br />permit predicted minor impacts to ground water and surface water. The impacts were predicted to <br />result from coal spoil leachate dischazge as described above. The observed hydrologic impacts aze <br />consistent with those predicted impacts and with those in the Division's Piedra River Cumulative <br />Hydrologic Impact Assessment. Based on the foregoing observations, the Division fmds that the <br />Chimney Rock Mine has minnnized disturbance of the hydrologic balance in the mine plan and <br />adjacent areas, and prevented material damage outside the permit azea. The Division also finds that <br />the Chimney Rock Mine has not caused hydrologic changes that adversely affect the approved <br />postmining land use in the permit azea. <br />Support of Post-Minin¢ Land Use <br />The vegetative cover on reclaimed azeas appeazs to be preventing rill and gully formation for storms <br />having a frequency of less than 10 yeazs. No evidence of slope instability was found on the <br />reclaimed lands. No tension cracks were found at the tops ofthe slopes and no compression bulges <br />were evident on slopes. <br />The reclaimed ]ands have vegetative cover composed of a variety of grasses, forbs, and woody <br />14 <br />