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It should be noted that undermining ~of the 3000- and 4000-lines was completed in <br />January 1993. The final monitoring survey for this report period was conducted in <br />June 1993. It is estimated that subsidence along this monitoring line was more than 95°~ <br />complete by the June 1993 monitoring survey. Further monitoring and analyses may <br />result in changes to values presented in this interim report. <br />4.1 3000-Line <br />The 3000-line is located along the centerline of the 2 Left longwall panel. The line <br />extends out from the longwall start-up room. Data from the 3000-line indicates that an <br />adjustment of -0.1 ft should be applied to the baseline elevations for the monitoring <br />points. This adjusted baseline is illustrated on the profile labelled Subsidence Line 3000. <br />These adjustments are not reflected on the current tabular summary of the data. The <br />corrections will be applied to the next report. <br />The angle of draw calculated for the 3000-line is approximately 18 deg for the 1050-ft <br />overburden depth. This is slightly greater than the projected 15 deg start profile draw <br />angle. <br />Maximum subsidence, corrected for the -0.1-ft baseline correction is 3.5 ft, or 42 in. This <br />is slightly less than the projected 44 inches of subsidence. The 8.7-ft mining height <br />results in a ratio of 0.41 for maximum subsidence to mining height. <br />4.2 4000-Line <br />The 4000-line is located perpendicular to the centerline of the 2 Left longwall panel. <br />The downdip side of the monitoring line did not extend outside of the active subsidence <br />area. The data indicate that the downdip angle of draw for the 4000-line is greater than <br />25 deg for the 1050-ft overburden depth. Previous subsidence monitoring at the Foidel <br />Creek mine site indicated an average downdip draw angle of 23 degrees. <br />The updip side of the monitoring line had a calculated angle of draw of approximately <br />32 deg for the 1050-ft overburden depth. Previous subsidence monitoring at the Foidel <br />Creek mine site indicated an average updip draw angle of 12 deg. The 32-deg angle <br />may be revised with further analysis of the data. <br />Maximum subsidence is approximately 3.6 ft, or 43 in. Using the 8.7-ft mining height <br />results in a ratio of 0.41 for maximum subsidence to mining height. This is slightly less <br />than the projected 44 inches of subsidence. <br />Grprus Txenrymile Seen-~nnwl suMitlenm Report <br />SeptemCr 13, 1pD7 Pape Z <br />