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

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{ _ ENVIRONMENT, INC. P^GE 3 ` JANUARY '29, 20 1-5 -of the affected land for this cross - section. AlterriMJVely,'the Applicant may reviselthe model perimeters to increase the factor of safety to 1.3 or greater. During my review of this cross - section I found that this cross- section's cut -line should be labeled C -C to match the Deere & Ault figures. In addition,-I found that i St. is shown as being adjacent to the permit line, when the edge of pavement is actudlly 25 feet east of the permit line. -I changed Section C- C-profile to move,the edge of ayement to the :true location and fixed the labe ling on -the cut -line on the-map as noted bove. 9 p Deere and Ault revised their analysis to calculate the factor of safety at a oint 5 -feet inside the permit /affected lands line. It shows that when the proposed set ticks: and slope mining method is used -at this mine then the safety factor at Section -C -is 1.71 and this is above'the 1.3 the Division requires. In addition, the slope stability m del,finds a failure slope that is over 10 feet into the bedrock. In our opinion we believ this' type of, failu "re.is unlikely -5_ -The 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 neede�. , -The le ends on the fi quires have been corrected and copies attached for the file. This did 9. g. p. - not have any effect on the results of the analysis. North Section - Section C -C - Haul Road 6. The Applicant's cross section was duplicated for verification. The safety factor-pr -duced b PP . _ P ,. Y P. , , Y . Galena -is significantly lower (1.18) than the�saf�ty factor produced ky the Applicant's model�(1•.3). Therefore, this slope configuration is_unacceptable for the North Section c'ro'ss section. -A copy of s= - .the ,Galena model is attached. The Divisiori`will requke'the Applicant to obtain sfructure agree meats for all property; ;including easement holders, and structure owners Within d 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 or`greater: During,my review of this cross- section I found that this cross section cut -li n6 should be labeled .D -D to .match the .Deere &Ault.figures. I fixed the labeling on Map •Exhibit C -1 _as noted- above. .Diet", Ault .revised their analysis to calculate the',Mctor -of -safety�at a point 5 feet - Jhside;=the permit /affected- lands_line. It show`s that - when the set. ticks and - ;. = sslope;_mining mefhod-is used af,this.mine then "the. safety factor -at Section -D. is 1.38 and -ahis'is above_the 1.3 fhe Division requires. In addition,•the slope'stabilitym del finds a . fa ilure slope thafi is over, 10 feet into, the bedrock: In our opinion we believe this type of. failur.'e 'is unlikely. - We have a signed `and notarized structur_.e -a ment:with Monaco 9011 LLC, -t he'property.owners on this-side of the mine. 7 - The Deere & Ault stability model reversed the cross - section positions of __verburden_and sand & gravel and labeled theasturry`wall as "band &Gravel ":'Please revieWthe° nalysis`model: antl t6ise the model as `needed. ' "` -