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Figure 9. Seeping fractures adjacent to the eastern extent of Room #1 portal and just above the <br /> sediment settling pond.Notice that the large seeping fracture dips into the site effectively <br /> preventing the possibility of failure down the slope. Furthermore, minor fractures terminate into <br /> this un-moveable fracture. View to the north, photo captured 180906. <br /> Pillar Design and Underground Structural Integrity <br /> The Rose Red Granite Quarry was historically mined as an open cut, readily observable in the <br /> tiered cuts above the current gallery openings. The Operator has undercut the historic highwall <br /> in three locations trending east-west. The western most cut is shallow and utilized as a <br /> processing area. There are no current plans to extend the western cut further under the highwall. <br /> The central cut is approximately as deep as the western cut but is planned to connect to the <br /> underground gallery based on previous plans submitted to the DRMS. The previously submitted <br /> room and pillar design would be more typical as an underground coal mine and is extremely <br /> conservative for an underground dimension stone quarry (Figure 10). The NIOSH Information <br /> Circular 9526, "Pillar and Roof Span Design Guidelines for Underground Stone Mines"was <br /> utilized to calculate the pillar safety factor for the submitted design. The calculation results in a <br /> safety factor of 15.3 (Esterhuizen et al., 2011). NIOSH recommends a minimum safety factor of <br /> 4.0. <br /> Rose Red Quarry Geotechnical Report 15 Greg I e "i and Aswiatm PIA d' <br />