2015-02-02_PERMIT FILE - M2014043 (2)

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} ENVIRONMENT, INC. PAGE 4 JANUARY 29, 2015 The legends on 'the figures have been corrected and copies attached for the ile. This did not -have any effect_ on -the results of the analysis.', t '. Phase 1 Section - Section E -E - Colorado Parks & Wildlife buildings 8. The Applicant's cross section was duplicated for verification. The safety factor produced by Galena is signifcantly1ower (0.74) than the safety factor produced . by the Applicant's model (1.3). Therefore, this slope configuration is unacceptable for the Phase 1 Section cross_ ection. A copy 5 of the Galena model is, attached. The Division will require the Applicant to obtain sructure - agreements for all property, including easement holders, and structure owners =wit in two hundred .. feet of the affected land for this cross - section. Alternatively, the Applicant may revise the model . perimeters to increase the factor of safety to 1.3 0r greater. " . During my review of this cross section I found that the labeling on the cut-Ii e; on Map K Exhibit C -1 -was wrong, it has been corrected on the attached version. t " - Deere and Ault revised their analysis to calculate the factor. of safety at a point 5 feet : inside the permit /affected lands line. It shows that when ,the proposed setbl eks and s slope mining method is used at this ,mine then the saf ety- factor at Section E E is 1.39 and --this is above the;1.3 the D_ ivisiori - requires. In addition, the -slope stability model finds the - failure,slopeji.xtends into the bedrock. In our.opinion we.believe:this type oflfnilure 'is u' likely.` ' 9...'.- _Jhe,,Deere: &Ault stability analysis model -reversed the cross- section,positions of overburden and sand & gravel. Please review -the analysis model and revise the model as needed. -; The legend on this= figure has•been corrected copies- attached for the file. 'This did not have any effect'on the results oft he analysis. General 10. In response to Item #3'in the Division memo dated December 18, 2014. The.Appli ant corrected s... _ cross= section`s C-C and D =D on Deere 8� Aulf Figure 6, revised to Figures 6 and T. The Applicant - failed to update`.the C -C and D -D cross- sections on' Exhibit C -) Mihing Plan Map." leasereview _ cross- sections C -G avid D -D 'on Exhibit C -1 Mining Plan Map and: revise the map cording�ly. "`• - The .cross sectlon-cut -lines bri the map were corrected =to match the,Deere.d d;Ault urey: -YCut =line for Section E =E was fixed too. The cross section profiles : re checked qnd Section; D =D ,was _fixed to show the true rely #ionship.'Mphaeo :5t: -has tot a permit line - ; to''nlatch the mnp (moved 25 feet east).` 11: Ttie Division- noticed several inconsistencies between- the;Deere; &:Ault stability an lysis cross- " `section profiles and,the cross - section ,profiles oh, Figure's,6 and 7.- Please review t e cross - sections profiles _for each section grid verify the'" match- exactly. _ . - Attached is arevised copy of -Map Exhibit C-1 = .Mining Pion Mnp showing :the Torrected S crosssections. 'They "now match the Deere- and=Ault,figu`res: -The cros,'s =secfii `n=pr`ofiles = r a. . `_ .shown on Figures 6 &7 .were used in the analysis program sojhey how "match. -0e have i;, .