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<br />Aggregate Industries Morrison Quarry GEI Consultants, Inc. <br />Geotechnical Addendum, 2016 Annual Report 16 January 2017 <br />4.3 South Quarry <br />Observations in the South Quarry on January 12 and January 13, 2017 indicate: <br /> No major failures occurred last year; <br /> Minor, localized sloughing and raveling occurred; <br /> Continued monitoring and mitigation of any additional loading of Bench 6820 <br />instability area caused by uphill mining activity is recommended; <br /> Areas of adversely dipping foliations observed at Bench 6600, Bench6850, and <br />Bench 7113 warrant extra caution when working near or below these areas. If the <br />evidence of instability or movement in these areas is observed, engineering <br />consultation is recommended <br /> The tension cracks adjacent to the highwalls below Bench 7113 and Bench 7270 <br />warrant extra caution working near or below these areas due to the potential for <br />minor toppling. <br />Observations of 2016 mining activity within the South Quarry appeared to follow the Permit <br />and the Mine Plan. 2016 mining increased the mine depth below El. 6,640 to El. 6600 at <br />Bench 6600 but did not increase the overall footprint of the South Quarry. Rock types <br />observed included granite and biotite or granitic gneiss with localized pegmatitic or mafic <br />intrusions. The majority of the rock observed in the highwalls appeared fresh to moderately <br />weathered, with the major exceptions located in highwalls proximal to the native topography. <br />Highwall trends, typically north-south or east-west, along with observed typical joint and <br />foliation orientations indicate favorable conditions to continue mining in accordance with the <br />current mine plan.