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Martin Marietta Materials <br /> Spec-Agg 2016 Annual Report <br /> discontinuity orientations used in previous reports; however, we noted some minor differences which we <br /> applied to our kinematic analyses for the 2016 Annual Report. <br /> The kinematic analysis for East Wall 2, Northeast Walls 2 and 3, Northwest Wall, West Walls 1, 2 and 3, <br /> South Wall, and Southeast Wall each indicate the possibility for wedge failures to occur. Additionally, the <br /> analysis for Northeast Walls 1 and 3 shows the potential for planar failure. The walls of the quarry in <br /> these areas should continue to be monitored closely as mining continues to assess the potential for the <br /> indicated failure modes to contribute to large-scale slope instability of a final mine highwall based on the <br /> properties, continuity, regularity, and variation in orientations of the discontinuities involved. <br /> We also recommend that known faults are tracked and observed in new exposures to confirm orientation <br /> and character for supplemental stability analysis, as needed. We expect the southern fault identified by <br /> Gable (1968) and in previous years site visits (Figure 3) may be exposed in other locations as excavation <br /> continue in the Southern Expansion Area. Additionally, the unmapped fault generally located in the <br /> central portion of the quarry may be exposed for mapping in the future. As recommended in the previous <br /> reports, evaluations will be conducted during future investigations to assess whether or not any of the <br /> foliation sets (F-1 through F-3) are caused due to localized faulting that may have resulted in "structural <br /> regions"that have created areas in which the varying orientation of the foliation planes occur. These <br /> questions will continue to be addressed as more data are collected. <br /> Localized raveling, especially along the south walls, is likely to continue. Continuation of the safety- <br /> minded policies already in place, which limit the height of the exposed highwalls as well as the <br /> reclamation of exposed highwalls as soon as possible following blasting and rock haulage, will aid in <br /> minimizing the potential for instabilities to occur. The quarry walls appear to be relatively dry and <br /> noticeably absent is any major seepage. However, any major changes in ground water seepage or <br /> hydrostatic conditions observed either from quarry walls or during production drilling activities should be <br /> characterized and reported to Lachel. <br /> February 8, 2016 Page 12 Lachel & Associates, Inc. <br /> Project 15364004.00 ©2016 All Rights Reserved <br />