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Mr. Rob Mangone <br />September 25, 2015 <br />Page 2 <br />m:\min\tc1\_fremont\m-85-43 red canyon\tr03\tr03par2015-09-25.docx <br />b. Where each is located in horizontal space, and <br />c. Be sure the appropriate final highwall configuration is represented based on the <br />currently approved final reclamation plan map. <br />2. The text and the “Final Bench Configuration, East Side, Looking Northeast” figure show <br />rock foliation roughly parallel to the interbench 0.25H:1V slope. If the interbench slope <br />is steeper than the foliation dip slope, significant local slope stability issues may present <br />themselves. Please comment on the local slope stability effects of this configuration. <br />3. It appears only Section Aʹ-A was analyzed in the three submitted analyses using the <br />Galena software. The Division believes it would be prudent to also evaluate a cross <br />section that transects the residential area above the quarry on the east side, as well as the <br />fault zone located on the eastern boundary of Phase 1 workings. See the referenced fault <br />on the Division’s Figure 1 (attached). <br />4. The second and third Galena analyses depict a 320-foot high slope at a 1H:1V slope. One <br />analysis uses the Spencer-Wright method, the other uses the Sarma method. No bench <br />configuration is depicted. Please clarify what is represented in these two analyses. <br />5. There are a number of older faults through the area, including one mapped directly <br />adjacent to the eastern boundary of the Phase 1 workings. This can be found on the Mount <br />Pittsburgh geologic quad (CGS Open File Report OF-06-05). The referenced fault needs <br />to be evaluated. Likely it would be a weak zone (think Pikeview) that would fail before <br />the rockmass in general. <br />6. The analyses assume no phreatic influence. The quarry may be "dry", but that doesn't <br />mean the fractures don't carry water seasonally, and wouldn't have some frost action that <br />could impact stability. Please provide some discussion on meteoric water in rock <br />fractures. <br />7. The closest "recent" fault areas are an unnamed fault about 6 miles north of the quarry, <br />and the Ute Pass Fault Zone that is about 5.5 miles northeast of the quarry. The faults do <br />not extend through the quarry, but both are capable of producing seismic influence if they <br />rupture. Was this factored into the 0.15 seismic stress factor? <br />8. The March 11, 2013 TR-03 Reclamation Plan Map shows a final highwall configuration <br />on the east boundary (roughly parallel to the Fremont County line and offset <br />approximately 200 feet west) up to 280 feet high that does not appear to be evaluated in <br />these analyses. Please address this eastern boundary configuration. <br /> <br />Please remember that the decision date for this Technical Revision is October 30, 2015. As <br />previously mentioned if you are unable to provide satisfactory responses to any inadequacies <br />prior to this date, it will be your responsibility to request an extension of time to allow for