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M w <br />Memo to Dave Berry <br />Bowie No. 2 Geotech Study <br />page 2 <br />hydrologic impacts. Many of these operational topics are addressed in order to <br />prevent the development of problems which might preclude reclamation of the <br />mined property to a beneficial use. The Division cannot approve any mine <br />permit until the applicant has demonstrated that the mine site disturbances can <br />be successfully reclaimed. Unravelling, meta-stable backfilled slopes do not <br />represent successful reclamation and will not be judged by the Division as <br />meeting the required mandate to return the mine site to a beneficial use. <br />My earlier geotechnical adequacy comments generally expressed my concern <br />that insufficient geotechnical information had been provided within the <br />application to demonstrate that the site could be reclaimed in a stable <br />configuration. The Maxim Technologies study, while it presents considerable <br />viable geotechnical information, does not solve this basic inadequacy. With a <br />change in emphasis, however, I suspect that the majority of the necessary <br />preliminary geotechnical information has been collected with which to <br />preliminarily address my concerns. <br />Specific Comments <br />Page 6 <br />In discussing the ancient landslide which covers the majority of the <br />proposed surface facilities area of the Bowie No. 2 Mine, the author <br />hypothesizes; "The ancient slide was probably triggered by a strong <br />earthquake and flowed as a viscous mass on the relatively weak shale <br />beds above and below the Rollins Sandstone and moved for a distance of <br />about 1 /4 mile during a time of a much wetter climate." Insufficient <br />evidence or rationale is presented within the report to warrant such a <br />sweeping morphology conclusion. Furthermore, the conclusion suggests <br />that a significant acceleration due to "a strong earthquake" was <br />necessary to overcome intrinsic strength and trigger the slide. The report <br />identifies two modern failures on the mine site which it hypothesizes <br />were caused by moisture and/or over steepening by erosion. Based upon <br />