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of the Report.However only the results from the bench slope geometry for 1.67:1 was provided <br /> under AppendixD.Additionally, it appears an error exists in Table 4 for bench slope geometry of <br /> 1.67H.1 V. The resulting slope stability analysis under Appendix D shows a FOS of].66 while <br /> Table 4 has a FOS of].63. Please have KUE provided a corrected Table 4(is necessary)and the <br /> slope stability analyses for the other bench slope geometries provided under Table 4. <br /> KUE:5A) Table was misnumbered and has been corrected to Table 6. 5B)Appendix D now <br /> includes stability runs for bench geometries of]:], 1.4:1 and].67:1 for both static andseismic. <br /> 5C)Appendix is correct and the text has been edited. <br /> The Division has reviewed the updated Table 6 (previously labeled Table 4) along with the additional <br /> discussion provided under the updated Section 6 of the Report.It is observed that new Factor of Safety <br /> (FOS)values have been provided not only with the requested results under seismic conditions but also for <br /> static conditions for each bench slope geometry discussed. These values are found to be larger than what <br /> was originally provided under the previously submitted Table 6 for static conditions. With that said, <br /> rational for the newly provided FOS values have been provided by KUE in the Report. <br /> The newly provided FOS values are the results of the stability analyses for long-term stabilization of the <br /> using the empirical strength parameters. Based on these results,KUE <br /> implemented an additional conservative approach to compensate for the potential of unknowns, such as a <br /> loss of internal granular cohesion or strength, by using a 701/o reduction to empirical limestone cohesion <br /> (1,500 psf).The use of this reduced cohesion in the stability analysis for the discussed bench slope <br /> geometries resulted in the values reported under the previously submitted Table 6. While not provided <br /> under a new table, these values are provided under discussion within Section 6 of the Report for static <br /> conditions with the slope geometries of 1.4:1 and 1:1. It should be noted that these analyses and resulting <br /> FOS are still applicable regarding the overall stope stability review for TR-6 in relation to the Rules and <br /> Regulations. <br /> With that said, discussion of the previously provided FOS result for the static 1:67 slope geometry was <br /> not provided as well as all seismic conditions under the reduced cohesion of 1,500 psf within Section 6. <br /> While some of the resultant FOS can be found under the associated modeling provided in Appendix D, <br /> for clarification and transparency,the associated FOS results for all bench geometries, static/seismic <br /> conditions and strength parameters which are discussed in the Report should be provided within the <br /> appropriate section. Similarly, all modeling results should be provided as well under the applicable <br /> section and or appendix for the Division's review. Please see the"Division's Comments and/or <br /> Questions" Section found at the end this Memo for additional comments. <br /> • Division:It appears the Division that inconsistencies exist with the material strength input <br /> parameters used within the analyses ofAppendix G when compared to the values provided under <br /> Table 2 of the Report.Additionally,a different failure plane angle was used in comparison to <br /> other analyses provided All models provided(excluding the back-analysis)should be consistent <br /> with the documented conditions and parameters representative to the Mine. Please request KUE <br /> ensure all input parameters for all providedstability analyses(excluding back-analysis)are <br /> consistent with the conditions and parameters associated with the Mine and haveKUE provide <br /> any updated analyses as necessary. <br /> KUE: 6A)KUE has clarified throughout the report that the models were run using the <br /> established empirical values for rock strength.Appendix G values forjoint strength and other <br /> joint parameters that dictate stabilization are included in Appendix G. 6B) The slope angle has <br /> been revised in Appendix G from Parameters across the report have been <br /> correctedas necessaryfor consistency. <br /> After reviewing the provided discussion and models within the Report,all input parameters for all the <br /> currently provided stability analyses and models are consistent with the conditions and parameters <br /> Mid Continent Limestone Quarry Geotechnical Review Memo February 6,2024 <br />