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<br />Memo to Dave Berry <br />Bowie No. 2 Additional Geotech Study <br />page 2 <br /> <br />It does not, however, provide significant information regarding the reclamation <br />of specific cuts and fill benches at the site. Further, it is limited by its <br />analytical assumptions. <br />As I stated in my earlier adequacy comments, the Division cannot approve any <br />mine permit until the applicant has demonstrated that the mine site <br />disturbances can be successfully reclaimed. Unravelling, meta-stable <br />backfilled slopes do not represent successful reclamation and will not be <br />judged by the Division as meeting the required mandate to return the mine site <br />to a beneficial use. My initial geotechnical adequacy comments generally <br />expressed my concern that insufficient geotechnical information had been <br />provided within the application to demonstrate that the site could be reclaimed <br />in a stable configuration. The original Maxim Technologies study, while it <br />presented considerable viable geotechnical information, did not solve this basic <br />inadequacy. This supplemental study, while it provides additional useful <br />information, leaves many of my earlier geotechnical concerns regarding the <br />earlier analysis unaddressed. <br />Specific Comments <br />Page 1; "Site and Subsurface Conditions" <br />This additional study addresses the backfilling of cuts similar to that of <br />the two highest benches. It generally assumes cut slopes of 2h:1 v in <br />original predisturbance slopes of 3h:1 v. This appears appropriate for the <br />two cuts analyzed. It does not appear to be an appropriate assumption for <br />many other cuts which will be generated by the proposed construction at <br />the site. For instance, the numerous switchback tight-radius turns <br />necessary to accommodate the proposed access road will probably result <br />in the excavation of high cut slopes with facial slopes steeper than 2h:1 v <br />in areas with predisturbance slopes of greater than 3h:1 v. The application <br />will have to specifically project the operational and reclaimed slopes to <br />be constructed and reclaimed before we can judge the propriety of these <br />modeled assumptions. For steeper reclaimed slopes it will be necessary <br />