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established against the highwall to isolate the spoils aquifer from the underground mine workings. Approximately <br />20,000 bcy of surficial materials high in clay and silt were required to construct a barrier berm about l5 feet in <br />thickness. An average depth of 1.5 feet of soil materials were removed from an area north of the portal pit to construct <br />the barrier. The suitability of the materials selected for the barrier is illustrated by the following textural analysis of soil <br />samples collected from the designated salvage site: <br />DESCRIPTION % CLAY % SILT % SAND <br />Loam-Clay Loam 27 47 26 <br />Clay Loam-Silty/Clay Loam 37 43 20 <br />Pit walls have been pre-split or trim-blasted to an angle of 65 degrees to the horizontal. Blasting was conducted in <br />accordance with all regulations and procedures presented in the Minor Revision of Technical Revision to Permit <br />No. 79-177, Area 1, Final Pit. The 68,000 bcy of blasted rock was utilized to partially backfill the old Area 2 <br />dragline pit, presently serving as the portal area to the 6,860 foot elevation, as described above. Highwall <br />modification and partial backfilling were designed to provide greater safety and enhance stability for the entrances, <br />by initiating the rock tunnels used for permanent entries in competent sandstone. <br />Detailed cross-sections of the final-cut that is being utilized as the staging azea for the Foidel Creek Underground <br />Mine are shown on Map 25, Surface Area Cross-Sections. <br />The spoils to the south of the portal azea were dozed down to a 2H:1 V slope to comply with stability requirements. <br />Three slope stability monuments have been installed as shown on Map 24, Surface Facilities and Freshwater <br />Systems. Past monitoring results indicate the slopes to be stable. Monuments will continue to be monitored and <br />the results submitted to CMLRD annually. <br />MR06-205 2.05-53.1 Revised -February 1, 2006 <br />