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Granite Quarry" dated November 2018. See page 11 for safety factors and pillar <br /> design associated with the underground workings of the Rose Red Quarry. <br /> Additionally, see the `Colorado Rose Red—Gallery Map' located in Appendix 2 <br /> of the above listed report to see changes to pillar design from the original map <br /> submission for AM-02. Changes to pillar design were required as mining has <br /> already cut into the previously designed pillar. <br /> f. DRMS Response 4: Based on your response above, if mining has already cut into <br /> the previously designed pillars, how does the applicant plan on defining and <br /> maintaining the proposed pillars and underground that are needed to maintain the <br /> proposed factors of safety? As underground mining progresses, the applicant must <br /> commit to submitting a detailed map of the location of the underground workings <br /> with the annual report. <br /> g. GLA Response 4: Mining had cut into the previously designed pillars prior to the <br /> designs execution—this is an error in drafting the previous design and does not <br /> reflect the Operator's ability to accurately follow the mine plan. The Operator will <br /> be able to accurately follow the new pillar design using their current mining <br /> procedures and techniques effectively maintaining the currently proposed factors <br /> of safety. The Operator commits to submitting a detailed map of the current <br /> extents of the underground workings with the annual report. <br /> 20. Regarding the proposed quarry operations (separate from the underground dimensional <br /> stone operation), the stability analysis conducted by Ground Engineering and submitted <br /> should not be used to draw conclusions regarding the stability of the proposed future <br /> mine benches and highwalls. As indicated on page 67 of the report, the evaluation may <br /> not contain sufficient information for other purposes. Given this, please provide <br /> engineering stability analysis for the proposed final reclaimed slopes/highwalls. Based on <br /> this evaluation, where there is the potential for failure of any geologic structure, <br /> demonstrate that off-site areas will be protected with appropriate factors of safety <br /> incorporated into the analysis. <br /> a. DRMS Response 3: The Division cannot conditionally approve the surface <br /> quarry as proposed. The applicant will need to provide the engineering stability <br /> analysis for the proposed reclaimed slopes/highwalls. If this cannot be done <br /> during this review process for this amendment application, please revise the <br /> proposed mining plan to remove the surface quarry operation. The applicant will <br /> need to submit a future amendment for the surface quarry operation. The Division <br /> would consider approval of a plan to finish mining in the former I I I c area and <br /> surface removal of the "spill area" material as this time. <br /> b. GLA Response 3: Surface fractures in the proposed drill and blast surface quarry <br /> are discussed and evaluated in the attached Geotechnical report generated by <br /> GLA titled "Geotechnical Analysis of the Colorado Rose Red Granite Quarry" <br /> dated November 2018. See page 5 for discussion on failure potential in the <br /> surface mining area as well as safety factors for mining in the same area of the <br /> Rose Red Quarry. <br /> c. DRMS Response 4: The Division is currently reviewing the Geotechnical <br /> Analysis. If Additional adequacy review issues are identified, they will be <br /> 4 <br />