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of subsidence continued until cessation of subsidence was accurately documented. None <br />of these conventional survey monuments experienced more than 1.0 foot of residual <br />subsidence, and the LWl subsidence monitoring program has been terminated as a result. <br />A description of the various phases of the subsidence monitoring program can be found in <br />Section III.A.7.1 of the permit application package. <br />Stipulation No. 49 of the January 17, 1992 Findings Document required that the applicant <br />propose a subsidence control plan for lease COC-51551 in accordance with Rule <br />2.05.6(6)(c). The terms of this stipulation were complied with through the submittal of <br />Minor Revision No. 72, which was approved on July 1, 1992. The minor revision <br />proposed a subsidence monitoring program for lease COC-51551. Subsidence of <br />azchaeological sites over LW-2, within lease C-023703, was found to not cause significant <br />impacts. Sites in lease COC-51551 were predicted to undergo less subsidence than sites <br />over LW-2. The archaeological sites in lease COC-51551 were never undermined, <br />however, due to mine plan changes which resulted from sealing of a portion of the "D" <br />seam workings due to a mine fire in January, 1996. <br />In summary, subsequent monitoring and observation have largely verified initial <br />subsidence impact projections. Current and future monitoring includes twice a year visual <br />inspection of mining azea RP-1, and monitoring of Scullion Gulch, County Road 65, and <br />stock pond reservoirs during periods of undermining. <br />The proposed operation is in compliance with the requirements of this section. <br />1X. (~neratinnc nn Alluvial Valley Flnnrc <br />The permit area and adjacent lands contain three stream channels -the White River, Red <br />Wash, and Scullion Gulch -with enough associated alluvium to be considered as potential <br />alluvial valley floors. All three channels cross the permit azea as well as the adjacent area. <br />The permittee's alluvial valley floor analysis is contained in Section II.D of the permit <br />application. Map 102 of the application shows the extent of alluvial deposits along the <br />three drainages. <br />Below is a detailed consideration of the alluvial valley floor potential of each of the <br />following three drainages: Red Wash, Scullion Gulch and the White River. <br />Geomorphic Characteristics <br />Red Wash is an intermittent stream valley, which crosses the southeast corner of the <br />permit azea. Red Wash receives drainage from both the northern portion and the majority <br />of the eastern portion of the permit azea. Several minor tributaries arise within the permit <br />area and drain eastwazd to Red Wash. Stock-water ponds are located in the Red Wash <br />42 <br />