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The results of the monitoring survey is presented on the attached table and profiles for <br />the monitoring lines. Analysis of the survey data indicates that the accuracy of the <br />monitoring survey is about 0.5 ft. Therefore subsidence values of 0.5 ft or less are not <br />considered significant. <br />Visual inspection of the monitoring lines in September showed no observable effects of <br />subsidence at the ground surtace. <br />The results indicate that subsidence has ceased within the mining area. <br />Data from the B-line resulted in final draw angles of 20 deg on the down-dip, or north end <br />of the line, and 12 deg on the up-dip, or south end of the line. Both draw angles are <br />significantly less than the 25 deg prediction used in the permit. <br />Maximum measured subsidence on the first longwall panel, 6 Left, was 3.5 ft at <br />monument A-4. This equates to a subsidence factor of 0.37 for the extracted seam <br />height of 9.5 ft. <br />Maximum observed subsidence occurred at monument B-7 above the second longwall <br />panel mined, 5 Left. Subsidence equaled 4.5 ft at this point. This equals a subsidence <br />factor of 0.47 for the 9.5-ft extracted seam height. <br />A subsidence factor of 0.54 was predicted in the permit. The observed subsidence <br />factors from the monitoring program are significantly less than the permit value. <br />The A-profile, noted as a centerline profile, was located off of the panel 6 Left center line <br />because of changes to the mine plan. Therefore, the resulting subsidence values <br />represent less than maximum subsidence. <br />Lyprvs Tventymile $emfmnaul SuMitleiaa Report <br />FsDrua7 1J, 1pW paps Z <br />