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<br />-2- <br />Subsidence Monitorin <br />Having predicted that no material damage will occur within the proposed <br />affected area due to the projected 5.5 to 8.0 feet of subsidy=_nce, the <br />applicant is required by Rule 2.05.6(6)(b)(ii) to conduct an appropriate <br />subsidence monitoring program. The amended permit revision application <br />includes an acceptable monitoring plan. <br />Empire Energy Corporation proposes to perform surface and subsurface <br />monitoring within and beneath the longwall mining area of the Utah Tract. <br />Their subsidence monitoring program has been specifically designed to provide <br />the following information: (1) To provide verification of the subsidence <br />predictions prepared for the proposed longwall area; (2) to r~~onitor the <br />response of selected slopes in the backfilled and reclaimed spoil area; and <br />(3) to monitor the responses of the topsoil stockpile, stock water pond dams, <br />and the surface access road. <br />The proposed monitoring program includes the installation of a set of surface <br />subsidence monitoring monuments. The proposed monitoring net:, consisting of <br />two lines of monuments, will be installed at the approximate location shown on <br />map IV-7. The subsidence monitoring monuments will be constructed as per the <br />criteria presented on page IV-198 of the permit revision application. Each <br />monitoring net monument line will extend across a two panel urea (panels No. 1 <br />and 2) and extend 400 feet beyond each ripside of those two panels. Monuments <br />will be spaced on l00 foot centers. These two subsidence monitoring monument <br />lines are depicted perpendicular to the long access of both panels. Two <br />center line monuments will be located adjacent to the perpendicular monitoring <br />lines, one either side of each line, at 100 feet from each line. In addition, <br />a partial axial monument grid line will be installed above the eastern end of <br />both panels No. 1 and IJo. 2, also on 100 foot centers. These monument lines <br />will extend across a sufficient portion of the end of the panel to observe the <br />angle of draw above the panel's end (See Map IV-7). All subsidence monitoring <br />monuments will be installed prior to development mining within the Utah Tract <br />area. Monuments will be surveyed on a quarterly basis. The surveys of <br />subsidence monuments will be conducted so as to provide vertical movement <br />data. Monitoring will continue until subsidence has ceased and MLRD <br />concurrence has been issued, in writing. Results of surveys for the <br />subsidence monitoring monuments will be reported to the Division on a <br />semi-annual basis. <br />Additional monitoring points will be installed on three grid lines on selected <br />slopes in the previously backfilled and reclaimed spoil area prior to <br />development mining beneath those areas. The proposed locations of these three <br />monitoring grid lines are shown on Map IV-7. Surveying of these monuments <br />will also be conducted quarterly, and results of these surveys reported to the <br />Division on asemi-annual basis. Monitoring of these slope stability <br />