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retained their monuments for future use if necessary. Monitoring of <br /> the south pains occurred until 1985, a year preceding a temporary <br /> cessation that lasted until April 30, 1989. <br /> The Divisicn now finds that the past subsidence monitoring has been <br /> sufficient to establish subsidence trends in the Roadside permit area. <br /> Since current mining activity is to the south, away from surface <br /> structures and drainage concerns , the Division finds at this time only <br /> visual reccnnaissance is necessary for this permit term. This should <br /> be sufficient to verify any subsidence impacts since the next five-year <br /> permit tern does not undermine any significant drainages or surface <br /> structures . Secondly, the geology, overburden thickness and coal seam <br /> extraction height remain the same as in previous mining areas that were <br /> monitored. Therefore , similar effects are predicted to occur. To <br /> ensure that this is indeed the case, the following stipulation is being <br /> added to tte permit at this time: <br /> Stipulatior No. 12 <br /> WITHIN 60 CAYS OF PERMIT ISSUANCE, A SURFACE VISUAL INSPECTION SHALL BE <br /> CONDUCTED ENCOMPASSING AREAS TO BE UNDERMINED IN THE NEXT FIVE-YEAR <br /> PERMIT TERN . THIS INSPECTION SHALL INCLUDE ANY SURFACE STRUCTURE OR <br /> FEATURE TO BE UNDERMINED. THESE FEATURES MUST BE DOCUMENTED AND <br /> PHOTOGRAPHED FOR HISTORIC RECORD KEEPING PURPOSES. <br /> FOLLOWING 1HE INITIAL VISUAL INSPECTION, A SEMI-ANNUAL INSPECTION SHALL <br /> BE CONDUCTED ON AREAS BEING UNDERMINED. THIS INSPECTION SHOULD INCLUDE <br /> ANY EVIDENCE OF SURFACE CRACKS OR SUBSIDENCE EFFECTS WHICH ARE TO BE <br /> MEASURED, FECORDED, MAPPED, AND PHOTOGRAPHED. THE RESULTS OF THESE <br /> SEMI-ANNUAL INSPECTIONS ARE TO BE SUBMITTED IN AN ANNUAL SUBSIDENCE <br /> REPORT, BY DECEMBER 31ST OF EACH YEAR, TO THE DIVISION OF MINERALS AND <br /> GEOLOGY. <br /> In additior , the permittee has installed subsidence monuments along the <br /> centerline of the Ute water pipeline . See Exhibits 29 and 30 for <br /> further information on monument location. The subsidence control plan , <br /> as presentEd by Powderhorn Coal Company within the amended application <br /> documents , is found to be in compliance with the subsidence-related <br /> regulation of Rules 2.05.6(6) and 4.20. <br /> The Ute Water Conservancy installed a waterline along the south and <br /> west perimEter of the Refuse Disposal Area in the winter of 1991 /1992 . <br /> Although tlis pile has remained stable since it was completed in 1984, <br /> care was tEken to protect the pipeline should any subsidence or <br /> settling occur. The waterline consists of a six-inch PVC pipe braced <br /> inside a tEn-inch P . I .P. encasement pipe where it crosses the refuse <br /> pile. Shotld a rupture of the PVC pipe occur it would be contained in <br /> the P. I .P. pipe and directed off the pile. <br /> XI . Operations on Alluvial Valley Floors <br /> The permitt:ee' s alluvial valley floor investigations in Section 2 .06 .8 <br /> of Volumes I and V of the application were reviewed for compliance . <br /> -39- <br />