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Martin Marietta Materials <br />Spec -Agg Project <br />It is noted that the results for the current analysis did not change the pole or the resultant concentration <br />center for any of the delineated joint sets significantly from any of the recent years' results. The collected <br />data for this evaluation was complimentary to the existing growing dataset and were consistent with past <br />analyses. <br />We have continued our analysis of the available cluster data to assess the hypothesis that two distinct <br />"structural blocks" exist within the quarry, and two cluster analyses showing the poles based on collection <br />areas have been developed (Figures 9 and 10). The datasets have been broken down based on the location <br />and year that the data were collected with the southern expansion area separated geographically from the <br />main pit area of the quarry (including the middle level) by the approximately east -west trending fault that is <br />mapped roughly between the two areas (Figure 3). Currently the 1997 -2002 data continue to be analyzed as <br />a single data set and are included in both the upper and lower analyses, but data collected since 2003 has <br />been separated for the analysis based on this potential boundary. For the current analysis, we merged the <br />2007 through 2012 data as a single pole due to a lower volume of data collected in recent years. The results <br />show that the data in the main pit have a tighter clustering around the primary discontinuity orientations <br />(Figure 9), but overall similar clusters were found in the expansion area, with only a weak fingerprint for the <br />F -3 discontinuity set differentiating the two (Figure 10). <br />The emergence of F -2 and F -3 as possible discontinuity sets were identified as the result of the 2003 <br />geotechnical investigation and have been lacking in subsequent year's investigations. The intersection of <br />the foliation planes (F -1, F -2 and F -3) with each other will not be evaluated in the wedge stability analyses <br />presented herein. <br />Overall, the discontinuity sets obtained by analysis of the entire dataset (i.e., 3108 points) are consistent with <br />the cluster analysis from previous years' individual analyses (Figure 7). Both of the foliation discontinuity <br />orientations, F -2 and F -3 are identifiable within the quarry, but have not been recorded in large enough <br />quantities to create a strong signature in the analysis of the entire dataset. However, based on the <br />prevalence of these discontinuities in the southern expansion area, both of these orientations continue to be <br />used in this analysis. <br />To adequately understand the impacts of the new data on wall stability, the planes representing each <br />discontinuity set within the total dataset and the plane representing the orientation of the respective quarry <br />wall slope face were plotted. The stereographic analysis of each quarry wall is presented in Figures 11 —16. <br />5.2 Wedge Stability Analysis <br />As presented in previous annual reports, the method of stereographic analysis developed by Markland <br />(1972) was used for this study. Markland's test is designed to identify the possibility of a wedge failure in <br />which sliding takes place along the line of intersection of two discontinuities (Hoek & Bray, 1977). <br />February 13, 2012 <br />Page 9 Lachel & Associates, Inc. <br />Project 11361017.00 ©2012 All Rights Reserved <br />