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appropriate. Please provide the Division with the corrected factors of safety, as <br />necessary. <br />Comment: The above referenced typographical and data transpose issues have all been <br />corrected in the tables included within the new Appendix D in Revised Addendum No. 3. <br />As stated in the opening paragraph to this Revised Addendum No. 3 Rev 1, it supersedes <br />all previous geotechnical reports and addenda on the issue of material strength properties <br />and slope stability evaluations. <br />31. The Division has noted certain discrepancies in the data presented in Table A-3 - <br />Results of Stability Analyses - Section C-C'. The CMS Cohesion value for Trials 1, 2, 5 <br />and 6 is listed as 750 psf rather than 706 psf. This may be a misprint in the table only; the <br />correct value appears to have been used in the Slope/W software for Trials 1 and 2 (pp 26- <br />27), but Slope/W printouts have not been provided for Trials 5 and 6, so we are unable to <br />determine whether correct values were used to compute the Factors of Safety reported. <br />Please review Table A-3 entries for CMS Cohesion and Factor of Safety and revise as <br />appropriate. <br />Response: The above referenced typographical and data transpose issues have all been <br />corrected in the tables included within new Appendix D in Revised Addendum No. 3. As <br />stated in the opening paragraph to this Revised Addendum No. 3 Rev 1, it supersedes all <br />previous geotechnical reports and addenda on the issue of material strength properties and <br />slope stability evaluations. <br />32. Note No. 1 on Figure 4 in the Shannon and Wilson report refers to Appendix B. The <br />report submitted to the Division included only Appendix A. Please provide Appendix B <br />for the Division's review. <br />Response: The Appendix B referred to in the original October Addendum No. 3 was <br />Appendix B of the Collom Temporary Spoil Fill as described in Note No. 3 of the same <br />Figure 4. That Appendix B presented geotechnical laboratory test results from a triaxial <br />compression test (TX/CU) for the natural valley bottoms clay soil that exists on some of the <br />profiles on the Collom and South Taylor pile sections. The test provides a better estimate <br />of the effective strength of the clay layer than was available at the time the South Taylor <br />geotechnical work was originally performed, which pre-dated the Collom work. However, <br />the triaxial compression test results were available by the time the October 21, 2009 <br />Addendum No. 3 was prepared, and were therefore used for the South Taylor piles as well. <br />Figure 4 of the October 21, 2009 Addendum No. 3 now appears as Figure 13 in the April <br />10, 2010 Revised Addendum No. 3, and the reference to Appendix B has been removed. <br />However, the reference to the Collom Temporary Spoil Fill Study remains in the new Figure <br />13. <br />33. On Figure 5, Curve No. 4, representing friction and cohesion for CO-3, has been <br />extrapolated to become Curve No. 6, the Lower Bound for stability analysis. The Division <br />questions whether an actual test result is appropriate for use as a "Lower Bound", in that <br />the number of samples analyzed is not excessive, and there may well be other soils that <br />are "worse" upon which the fill may be constructed. Please provide additional rationale <br />for the selection of the Lower Bound for the clay overburden.