Laserfiche WebLink
Above the two panels investigated for the South Mine, the vegetation is typically a <br />pinion~uniper woodland. This dense vegetation limits the amount of the area that the <br />• observer can see from one location. Photographs of the area were taken from near the <br />base of the cliff that would be directly above the 7th East panel and from the ridge over the <br />end of the 6th East Panel. These photographs were aimed at the areas where the lower <br />cover would increase the possibility for subsidence features. No subsidence features were <br />noted in the areas that were inspected. <br />Subsidence Surveys <br />Stipulation 12 also requires that five subsidence monitoring stations in Jerry Creek <br />and Coal Canyon be surveyed. Two surveys were conducted during 1998. These surveys <br />were done utilizing Global Positioning Satellite technology. Some discrepancies with the <br />earlier surveying data were apparent. In fact, the original elevation of the points were <br />calculated to be lower than those measured with the more accurate GPS system. Exhibit 1 <br />contains a letter from Mr. Earnest E. Schaff, PLS regarding the results of the GPS surveys <br />conducted during 1998 and a recalculation of the earlier data with corrections for curvature <br />and refraction. Table 2 shows the results of the various surveys with both adjusted and <br />• unadjusted data. The results presented indicate that there has been no subsidence at any <br />of the measured locations. <br />Minimizing Subsidence <br />Since no mining is going to take place in the South Mine in 1999, there should not <br />be any new areas where subsidence will occur. At the North Mine, the technique of <br />aligning the North West mains with Jerry Creek will afford extra protection for the creek bed <br />since no second mining will take place in this area. <br />Conclusion <br />There is no evidence that any subsidence related dammage has occur-ed in the last <br />year. No dangerous subsidence related features were located during the surface <br />investigation or survey of the subsidence monuments. The operetor has not been noted <br />that subsidence has effected any structures, water supplies, or other highly sensitive <br />areas. Some limited subsidence may have occurred but gone unnoticed because of its <br />limited nature and the lack of any effect upon sensitive areas or structures. <br /> <br />1998 Subsidence ~ Pape 4 12-31-98 <br />