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/unc 1992 Cyprw TCC • Pttdu:tion of Subsufrncc F/jcru • 7 <br />• 2. Calculating maximum rubsidence for the inaeaxd width of Panel 6; <br />(a) estimate S/m for 625 feet panel width using the Subsidence Engineer's <br />Handbook (NCB, 1975): S/m - 0.58 <br />(b) estimate S/m for 850 feet panel width using the Subsidence Engineer's <br />Handbook (NCB, 1975): S/m - 0.73 <br />(c) calculate the ratio of S/m factors (b)/(i): ratio - 1.26 <br />(d) calculate the maximum subsidence for Panel 6 by multiplying the <br />maximum subsidence value for the 625 feet wide panel (53 inches) by the <br />ratio calculated in (c): S„~ - 67 inches. <br />3. Calculate the transverx subsidence profile for Panel 6 using Table 1, Page 14 of <br />the Subsidence Engineer's Handbook (NCB, 1975). As shown in Table 3, this <br />results in a modest over-prediction of subsidence outside the panel ribs. This <br />action is centered over Panel 6 directly south of Panel 5's start room and reflects <br />conditions prior to interaction of rhea two panels. <br />4. Overlay the transverx profile for Panel 5 and Panel 6 and incorporate subsidence <br />data from survey line 12000E for conditions over the rigid-yield pillar pair. This <br />xttion is plotted west of Panel 5's start room where conditions of full interaction <br />will exist. <br />• 5. Calculate Panel 6's start profile using a maximum subsidence of 67 inches and <br />Figure 32 of the Subsidence Engineer's Handbook (NCB, 1975) <br />6. Adjusting subsidence limits for start and transverx profile draw angles of 15 and <br />17 degrees respectively and constructing rubsidence contours by tnt per o anon <br />between start and transverx profile data for each panel. <br />Baseline data for Panel 5 and 6 and data points for the predicted transverse rubsidence and star <br />profiles are shown in Tables 12 and 13 respectively. Corresponding contours are plotted on <br />Map 3, Subsidence Associated with Panels 5 and 6. Subsidence within the designated Fish Creek <br />AVF is projected to range from 0 to 48 inches over the average AVF area width of <br />approximately 500 feet and over a distance of 1,800 feel along [he drainage axis. - <br />6.0 REFERENCES <br />Coe, C.J., and Stowe, S.M., 1984. Evaluating the Impact of Longwall MininP on the Hydrologic <br />Balance. In Proceedings of the National Water Well Assocation Conference on Impatt <br />of Mining on Ground Water, National Water Well Association, Dublin, Ohio, pp248- <br />259. <br />Haxnfus, G.J., Johnson K.L., and Su, D.W.H., 1988. A Hydrogeomechanical Study of <br />Overburden Aquifer Responx to Lonewall Underminittg. In Proceedings of the Seventh <br />International Conference on Ground Control in Mining, COMER, West Virginia University, <br />Morgantown, WVA, pp 149-162. <br />• Haramy, K., 1992. Personal Communiption. <br />.1 CZ lru. • P.O. Box 771018 • Srtambaat SPnngt, Colorado 80!77 •(303)8796160 <br />