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19. According to page 65 of the application the interior roofs of the `rooms' were not <br /> included in the stability evaluation performed for this study. Please provide a <br /> geotechnical evaluation of geologic hazards associated with the existing and proposed <br /> underground roofs and `rooms.' Based on this evaluation, where there is the potential for <br /> failure of any geologic structure caused or exacerbated by the existing and proposed <br /> underground mining operation please demonstrate that off-site areas will be protected <br /> with appropriate factors of safety incorporated into the analysis. <br /> a. DRMS Response 3: The Division will not approve any additional underground <br /> mining without a geotechnical evaluation demonstrating off-site areas will be <br /> protected with appropriate factors of safety incorporated into the analysis in <br /> accordance with Rule 6.5(3). Here are the applicant's options: <br /> i. Provide the geotechnical evaluation. OR, <br /> ii. Commit to cease and desist from all underground mining operations and <br /> revise the proposed mining plan as such. <br /> iii. Please be aware that Colorado Rose Red's underground mining operation <br /> is currently out of compliance with the approved mining plan. The <br /> Division may take enforcement action is this adequacy issue is not <br /> addresses to the Division's satisfaction and underground mining <br /> continues. <br /> c. GLA Response 3: Fractures along the interior roofs of the underground workings <br /> are included on GLA Map `Colorado Rose Red—Gallery Map.' Underground <br /> fractures are discussed and evaluated in the attached Geotechnical report <br /> generated by GLA titled "Geotechnical Analysis of the Colorado Rose Red <br /> 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 /> 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 /> 3 <br />