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.,;, .' Memo to Dave Berry Bowie No. 2 Geotech Study page 6 required compacted densities. Fills constructed to these higher density standards, if wetted, could swell extensively disrupting their structure and decreasing their shear strength significantly, resulting in structural failure. Fills design and constructed to lesser shear strength standards may have much greater likelihood of survival if wetted. The author states; "Slope sections in the portal bench area generated factors of safety in the range of 1.2 to 1.4, considered marginal to acceptable for a project of this type." While these safety factors may be considered acceptable in general engineering practice, the applicant must meet the minimum slope stability safety factors specified throughout our regulations. Among other specified requirements, all reclaimed surfaces must meet a minimum static slope safety factor of 1.3. Page 18 In the only direct address of reclamation of the site, Maxim Technologies states; "It is our opinion that returning the site to original grades will be successful if the criteria for fill placement are followed. We do not recommend placing permanent, reclaimed slopes at inclinations steeper than 2H:1 V. The use of benches to control slope drainage and erosion and promote revegetation should be incorporated into the reclamation plan." The implications of this recommendation are significant. First, every backfilled cut or reduced embankment will be reworked as if a structural fill were being constructed. This includes benching and scarifying of areas to receive backfill, complete compaction and verification of fill density, proper drainage and storm water management. Further, bonding will be required to complete all of this work in the event of forfeiture, including monitoring to verify success. Candidly, this is a standard that few mines have proposed to meet. However, based on the preliminary materials information provided in this report, I concur with Maxim's recommendation.