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Ms. Christine Johnston <br />Mountain Coal Company <br />Page 14 <br />April 14, 1997 <br />to assure minimal slope creep". Within high risk zones they concluded; <br />"Area not safe for construction and should be monitored for movement. <br />Preventive action advised for this area, such as improved drainage, <br />additional buttressing, and additional vegetative cover". Envirocon's risk <br />map included areas immediately upslope from the power substation bench, <br />and immediately upslope from a significant portion of the lower access <br />road within the high risk zone. The map also delineated the slopes <br />immediately surrounding the shafr bench area, the proposed location of the <br />electrical substation, and the majority of the remainder of the slopes <br />immediately upslope from the access road within the medium risk zone. <br />The majority of the light access road alignment along the proposed <br />powerline alignment was apparently not mapped by Envirocon, Inc. <br />"Geology Map" by IntraSeazch - 1 ]/94 <br />This aerial photographic reconnaissance geology map of the SGFA is referenced <br />by several of the other investigators but was not supplied in the submittal. Based <br />upon comments by the other investigators it is appazently relatively <br />"conservative", i.e. it identifies several areas as landslides with which other <br />investigators disagree. <br />"Landslide Map for West Elk Application" by John W. Rold - 2/95 <br />John Rold provided a drafr map of landsliding at the West Elk mine site. Dr. <br />Rold's discussion refers lazgely to the earlier mapping by IntraSearch, Inc., as a <br />base. John recommends the addition of several "large landslides" not identified <br />by IntraSearch, Inc. and also disagrees with several landslides identified by <br />IntraSearch, Inc. In the vicinity of the SGFA. Dr. Rold closed his memo by <br />recommending that the various investigator's interpretive disagreements "should <br />be resolved if any surface uses are planned in this area for the future". <br />"Sylvester Gulch Landslide Analysis" by Tilt & Clanton - 7/95 <br />Following Dr. Rold's report, Tift and Clanton performed a subsequent analysis for <br />the expressed purpose "to address the conflicting information that had been <br />presented by previous studies". Tilt & Clanton appear to have performed more <br />extensive field reconnaissance than previous investigators, in an attempt to field <br />verify interpretively mapped landforms' geomorphology. Similar to John Rold, <br />Tilt & Clanton identified several additional landslide landforms and disagreed with <br />several previously identified by other investigators. R. Tifr closed his brief report <br />with the following recommendation: "Prior to finalizing plans for specific <br />locations of surface facilities, further site specific review should be conducted. In <br />