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the West Mine. Several of the 90 series sites, 94, 96, 97 and 98, are located on structures owned <br />by the Grosse-Rhode Ranch. The PL series subsidence monuments have been established above <br />the Pitkin Mesa pipeline. <br />A number ofhigh-resolution, closely spaced subsidence monuments have been installed in sites <br />selected throughout the existing permit area. Monitoring stations No. 201 through No. 224 are <br />installed above projected fault traces in an attempt to discern the effects of differential subsidence <br />between alternating fault blocks. Stations No. 42 through No. 51 are located in areas of thick <br />overburden. Stations No. 28 through 41, in contrast, have been installed above overburden <br />thicknesses considered typical throughout the permit area. <br />The high-resolution subsidence data will be used to evaluate and further define the projected <br />angle of draw. Data collected from these monument grids will allow verification, or support <br />redesign, of the subsidence control plans proposed by the operator for implementation in the <br />future. <br />On May 10, 1996, the West Mine experienced a large bounce in Panel 2 Right. The pillaring plan <br />at that time was subsequently revoked by the Mine Safety and Health Administration (MSHA). A <br />modified plan, allowing only the mining of bottom coal in certain areas, was approved by <br />MSHA. <br />BRL submitted Technical Revision No. 16 to the Division in October 1991. The revision <br />allowed BRL to temporarily discontinue subsidence monitoring over inactive portions of the <br />original mine, which have been seated since 1986. Annually submitted subsidence data has <br />indicated that the area has stabilized. The Division approved the revision February 11, 1992. <br />The subsidence portion of the application is in compliance with the Regulations. <br />XVI. Concurrent Surface and Underground Mining- Rule 4.22 <br />This section is not applicable to the Bowie No. I Mine. <br />XVTI. Operations on Alluvial Valley Floors -Rule 4.24 <br />The discussion of Alluvial Valley Floors can be found on pages 5-6, Section 2.06 of Volume 1; <br />in the AVF Appendix A, Volume 4 and in the Geo-Hydro Phase 2 studies. <br />Identification of Alluvial Valley Floors <br />The general area in which the Bowie No. I Mine is situated contains several deposits of <br />alluvium. These alluvial deposits are derived from three sources: I) Flood-plain alluvium (Qal) <br />along the North Fork of the Gunnison River; 2) Valley-fill deposits (Qvf) along a portion of <br />Steven's Gulch; and 3) Alluvial gravel (Qag) divided into three (3) age categories younger <br />(Qagy), middle (Qagm) and older (Qago). The valley fill deposits aze located along the North <br />Fork Valley side slopes. <br />The applicant has identified alluvial/colluvial deposits in a second azea that is located along <br />Steven's Gulch in the W V2 NW V4 of Section 13, TI3S, R92W. As identified in the Phase I AVF <br />Study, the area is approximately 20 acres in size and is composed of valley-fill deposits (Qvt). <br />The mine has a well in this deposit that can pump 30,000 GPD from the alluvium/colluvium. <br />Depth to water vazies from about 7 Feet in May to approximately 36 feet in February. The area is <br />39 <br />