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<br />Memo to Dave Berry <br />Bowie No. 2 Second Additional Geotech Study <br />page 3 <br /> <br />of Rule 4.14, which addresses backfilling and reclamation stability, all <br />reclaimed permit areas, including roads, must achieve a minimum static slope <br />safety factor of 1.3. MAXIM's above quoted statement appears to be an <br />understandable, an not uncommon, hybridization of the above regulatory <br />requirements. Further, as I will discuss below, I believe MAXIM has provided an <br />appropriate geotechnical analysis to justify the approval of the proposed road <br />cut configurations at the projected slope safety factor of 1.4. <br />Because an additional conclusion may be implied in MAXIM's paragraph quoted <br />above, I believe an additional point of clarification is warranted. The Division <br />has not approved the retention of the roads at the Bowie No. 2 mine in their <br />operational configuration. Roadways may be retained, if requested by the <br />landowner. However, those roadways, in keeping with all other reclaimed <br />configurations, should be in a configuration which the Division finds to be <br />appropriate for the post mining land use. As an aside, because maintenance <br />efforts change from operation to reclamation, roadway configurations deemed <br />acceptable to the Division during the operation of a mine may not be considered <br />acceptable for the long term reclaimed situation. The Division may approve the <br />retention of the roads, but may require that the fill embankments be reclaimed <br />and / or the road cuts be partially backfilled in order to increase structural or <br />erosional stability, or to render the final configuration more compatible with <br />the post mining reclaimed landscape and land use character. <br />Specific Geotechnical Comments <br />The five stability analyses contained within the report are acceptable. Three of <br />them present analyses of road cut and fill situations judged by MAXIM to <br />represent the most critical cross sections. I concur with their choices. The <br />additional two cross sections chosen for analysis represent representative <br />sections through the topsoil pile and its underlying foundational slope. MAXIM <br />employed the Geoslope 4.0, with which the Division is familiar. The material <br />shear strength parameters chosen by MAXIM appear appropriate. In the case of <br />the road cut slopes, MAXIM applied a range of soil cohesion (2,000 to 3,000 psf) <br />for the weathered cut slope materials, because the strength of the stiff <br />