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With the exception ofthe ruins depicted as Structure No. 27, the inventoriedbuildings have <br />been protected by the retention of solid coal pillars of 300 -foot radius beneath each of the <br />potentially affected buildings. <br />The operator's strain projections anticipated potential, repairable damage (non -material <br />damage) to the twv existing water pipelines, the Steven's Gulch Road, assorted trails, <br />ponds, and springs within the permit area. In each case, a preferred repair methodology <br />has been presented within the Subsidence Repair Handbook portion of the permit <br />application (Volume 3). <br />Calculations were included in the permit application to demonstrate that adequate water <br />storage exists in the Pitkin Mesa Pipeline water distribution system to assure adequate <br />water supplies in the event of subsidence related disruption to the pipeline. The company <br />did not propose to mine pillars beneath the Pitkin Mesa Pipeline. Only development <br />mining of main entrieswere to occurunder the pipeline andthe Steven's Gulch Road within <br />the Steven's Gulch buffer zone and no subsidence was projected. BRL submitted a pipeline <br />repair plan, signed by Pitkin Mesa Pipeline Company as a condition of the approval of <br />TR -19. <br />Technical Revision No. 22 modified the coal lease and permit boundary to the west. The <br />revised permit boundary included areas in the Long Draw Drainage. Upper Cabin Spring, <br />water supply for Stucker Mesa Domestic Water Company, is located in the upper reaches <br />of this draw. BRL submitted to the Division a signed copy of a water replacement plan <br />agreement between BRL and Stucker Mesa Domestic Water Company (see PAP, <br />Volume IA, Section 2.05.6). <br />Subsidence Monitoring Program <br />BRL maintains a subsidence monitoring program for the Bowie No. 1 Mine. Originally, <br />the program consisted of four components; visual inspection, wide -spaced grid subsidence <br />monuments, closely spaced, high-resolution subsidence monuments and the monitoring of <br />specific buildings and structures. However, with the suspension of mining operations in <br />December of 1997, the subsidence monitoring program hasbeen reduced in size and scope. <br />The visual inspection phase is still in effect andconsists of a walkover ofthe ground surface <br />above mined areas on a semiannual frequency. The applicant also commits to daily <br />inspection of the Steven's Gulch road, in order to protect the public. <br />BRL received approval to suspend the wide -spaced grid subsidence monitoring program. <br />Monitoring stations No. 1 through No. 27 had comprised a wide -spaced monument grid on <br />approximately 1300 -foot centers east -west and 2600 -foot centers north -south. These <br />monuments provided general observations regarding the magnitude of vertical subsidence <br />occurrences. Although not required, monument stations 6, 14 and 15 continue to be <br />monitored twice a year and the results submitted to the Division in the Annual Report. <br />Additional wide -spaced monuments No. 70 through No. 87 had been installed above <br />proposed mine workings adjoining the old east portals. Monuments with the notations of <br />