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., Memo to Berhan Reffelew Carlton Tailings Lift Thickness - Supplemental page 2 normally assumed to represent a fast loading situation in which the material is unable to drain, resulting in a plastic mode of material performance. This represented but one possible scenario for the relocated Carlton Mill Tailings fill. More normally, tailings are assumed to be cohesionless when evaluating the conceptual stability of tailings structures. In response to my second set of adequacy comments, Golder reanalyzed the short term scenario for the Carlton Tailings fill. Mr. Manziac assumed a more traditional tailings strength assumption of zero cohesion and a sensitivity range of conservative p values, with a sensitivity range from 10° through 15°. The original laboratory value for the tailings friction angle was 38°. This sensitivity style analysis projected a minimum static factor of safety of 1.2 in the short term for tailings placed at lower densities in unsaturated/drained conditions. Long Term Scenario Further, Golder Associates addressed my long term concern regarding the placement of a low strength foundational layer of relocated Carlton Mill Tailings beneath the Arequa Gulch excess overburden fill and adjoining structure. I was concerned that this might facilitate a large scale rotational or glide failure, even though the relocated highway embankment would buttress the toe. Such a rotational failure could override the highway embankment with a large scale compression ridge or material flow, obliterating the surface and underdrain hydrology controls and conceivably subjecting the public to a health and safety risk within the relocated right-of-way. In order to evaluate this scenario, Golder repeated the original permit application stability analysis for the gross cross-section transecting the thalweg of Arequa Gulch and the adjacent and superimposed excess overburden structure. Lacking specific Carlton Tailings material properties for lower densities, Golder performed a similar sensitivity style evaluation. Mr. Manziac assumed a more traditional tailings strength assumption of zero cohesion and a sensitivity range of conservative p values, with a sensitivity range from 15° through 25°. Once again, this sensitivity style analysis projected a minimum static factor of safety of 1.2 in the long term for tailings placed at lower densities in unsaturated/drained conditions. Summary Comments The more thorough supplemental short term and long term sensitivity style stability analysis demonstrates the relocated Carlton Mill