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2 . The applicant has also proposed and implemented a <br /> subsidence-monitoring program, in accordance with Rule <br /> 2 . 05 . 6 (6) (c) , designed to determine the commencement and <br /> magnitude of subsidence movements . Map 17 , "Mine Plan <br /> Map" , depicts the locations of monuments that have been <br /> installed and structures that are monitored within the <br /> permit and adjacent area. The results of the monitoring <br /> program are submitted to the Division semi-annually. The <br /> monitoring program is designed to extend for a time, <br /> beyond cessation of mining in any area, consistent with <br /> the need for verification of the subsidence prediction. <br /> The monitoring plan details can be found on pages 2 . 05 . 6- <br /> 59 through 63 of the permit application. <br /> An initial study conducted for the mine predicted <br /> probable maximum subsidence depths of 1 .46 to 3 .22 feet . <br /> From 1884-1994, subsidence due to the mining operation <br /> was 0 . 03 to 2 . 19 feet. Since these depths are within the <br /> projected occurrences, the Division approved the <br /> applicant ' s request to reduce the monitoring frequency of <br /> some subsidence monuments from quarterly to semi- <br /> annually. Semi-annual monitoring is performed for the <br /> Newlin Creek streambed. The Florence water line and <br /> Thompson Ranch structures are monitored quarterly. <br /> Based on a review of semi-annual subsidence reports, the <br /> Division requested that the minimum angle of draw be <br /> increased to 25-29 degrees, based on data from the <br /> reports . This was incorporated into a stipulation from <br /> the 1991 Mid-term Review that stated: <br /> Stipulation No . 21 <br /> THAT THE OPERATOR PROVIDE BY DECEMBER 31, 1994 AN <br /> EXPLANATION FOR THE DATA INDICATING 27-29 DEGREES FOR AN <br /> ANGLE OF DRAW FOUND IN THE MAY-OCTOBER SUBSIDENCE REPORT, <br /> AND AS PART OF THE EXPLANATION, PROVIDE TO THE DIVISION <br /> BY DECEMBER 31, 1993 , APPROPRIATE SUPPORTING <br /> DOCUMENTATION ACCOMPANIED WITH AN EXPLANATION OF THE <br /> ERROR BY THE SURVEYOR THAT THE DATA IS THE RESULT OF <br /> SURVEY ERROR AND NON MEASURED SUBSIDENCE. <br /> In a letter received from EFCI, dated January 17 , 1994 , <br /> the response to the stipulation was to revise Map 17 to <br /> reflect an angle of draw at 29 degrees and to adjust the <br /> Southfield Mine Permit Renewal 03 <br /> 53 <br />