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-55- <br />additional "safe areas" of limited extraction be tied to the <br />detailed results of the analysis being performed upon the landslide <br />deposit above the Town of Somerset. <br />The Division finds that the following stipulations are necessary <br />for a finding of compliance with subsidence related requirements of <br />Rule 2.05.6(6) and 4.20. <br />Stipulation No. 13: THE DIVISION DIRECTS WECC TO COMPLETE THE <br />INSTALLATION OF THE SUBSIDENCE MONITORING NETWORK PRIOR TO THE <br />INITIATION OF EXTRACTION OF COAL WITHIN THE PANEL DESIGNATED IN <br />APPENDIX A TO THE NOVEMBER, 1984 PERMIT REVISION APPLICATION <br />ENTITLED "APPLICATION TO REVISE THE MINING AND RECLAMATION PLAN FOR <br />THE MT. GUNNISON N0. 1 UNDERGROUND MINE". THIS MONITORING NETWORK <br />IS DESIGNED TO MONITOR THE FIRST PANEL WEST FROM THE SW MAINS <br />INTAKES AND SOUTH OF THE NO. 1 WEST SUBMAINS, DESIGNATED AS "PANEL <br />1W-1S", LOCATED ADJACENT TO AND PARALLEL TO THE WESTERN BOUNDARY OF <br />SECTION 21, RANGE 90W, TOWNSHIP 135. THIS MONITORING NETWORK SHALL <br />CONSIST OF SUBSTANTIAL MONUMENTS DESIGNED TO RESIST FROST-NEAVE, <br />FIRE, AND THE ACTIONS OF CATTLE AND WILDLIFE. <br />Stipulation No. 14: THE SUBSIDENCE MONITORING NETWORK SHALL BE <br />SURVEYED UTILIZING CONVENTIONAL GROUND SURVEYING TECHNIQUES, <br />DESIGNED TO ACHIEVE HORIZONTAL ACCURACIES COMPLYING WITH THE U.S. <br />DEPARTMENT OF COMMERCE'S "SECOND ORDER, CLASS II" SURVEY STANDARDS, <br />AND VERTICAL ACCURACIES NO LESS THAN + 0.2 FEET. THIS GRID SHALL <br />BE SURVEYED TWICE PRIOR TO THE INITIATION OF SUBSIDENCE. IN <br />CONJUNCTION WITH THESE SURVEYS WECCC SHALL SELECT AND ESTABLISH A <br />MINIMUM OF SIX TRIANGULATION BENCH MARK MONUMENTS OUTSIDE THE AREA <br />OF ANTICIPATED SUBSIDENCE EFFECTS, FOR THE PURPOSE OF CORRELATION <br />WITH AERIAL PHOTOGRAMMETRIC POST-SUBSIDENCE SURVEYS. <br />Stipulation No. 15: WECC HAS REQUESTED PERMISSION TO COMPLETE A <br />PRE-SUBSIDENCE AERIAL PHOTOGRAMMETRIC SURVEY OF THE SUBSIDENCE <br />MONITORING GRID, FOR THE PURPOSE OF CORRELATION WITH THE FIELD <br />SURVEY RESULTS. IT IS WECC'S INTENTION TO UTILIZE AERIAL <br />PHOTOGRAMMETRIC METHODOLOGY TO MONITOR POST-SUBSIDENCE MOVEMENTS OF <br />THE SUBSIDENCE MONUMENTS. THE RESULTS OF THE PRE-SUBSIDENCE FIELD <br />AND AERIAL PHOTOGRAMMETRIC SURVEYS SHALL BE COMPARED FOR EACH GRID <br />MONUMENT. THE AERIAL SURVEY WILL BE ACCEPTED AS ACCURATE AND WILL <br />BE USED FOR SUBSEQUENT POST-SUBSIDENCE MONITORING, IN THE EVENT <br />THAT THE AERIAL PHOTOGRAMMETRIC AND FIELD SURVEYS CORRELATE WITH AN <br />AVERAGE SURVEY POINT LOCATION DEVIATION OF LESS THAN 0.2 FEET <br />VERTICALLY AND HORIZONTALLY, WITH SURVEY POINT LOCATION DEVIATIONS <br />OF LESS THAN 0.4 FEET VERTICALLY AND HORIZONTALLY FOR LESS THAN 95% <br />OF THE SURVEY POINTS, AND WITH NO SINGLE SURVEY POINT LOCATION <br />DEVIATION VERTICALLY OR HORIZONTALLY IN EXCESS OF 0.8 FEET. <br />Stipulation No. 16: WECC HAS REQUESTED PERMISSION TO COMPLETE <br />AERIAL PHOTOGRAMMETRIC SURVEYS OF THE SUBSIDENCE MONITORING GRID <br />SUBSEQUENT TO THE INITIATION OF SUBSIDENCE, FOR THE PURPOSE OF <br />MONITORING SUBSIDENCE MONUMENT MOVEMENTS. THE ACCURACY OF THE <br />AERIAL PHOTOGRAMMETRIC SURVEYS SHALL BE DETERMINED BY A COMPARISON <br />