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<br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />2.0 Summary and Conclusions <br />The results of the structural geologic evaluation for the Spec-Agg Quarry, which <br />included field observations, geologic mapping, and stereographic analysis of <br />structural geology data, indicate that the current quarry configuration is stable <br />under the existing conditions and current rock mass assumptions. The stability <br />of each of the slopes is enhanced by the absence of significant hydrostatic <br />pressures, by current mining procedures, and by the current reclamation <br />process. <br />~< Based on data collected from the current study, an-additional foliation orientation <br />may be emerging. For this report, this potential new foliation set is designated <br />as F-3. To date, not enough data has been collected to fully develop a <br />hypothesis regarding the location, extent and properties of the foliation; or to <br />eliminate the possibility that F-3 is basically a signature of the undulating nature <br />of the existing foliation set. The stereographic analysis indicates that the F-3 <br />discontinuity plane may only have minor influence on the south walls, and will not <br />influence the north, west or east walls. <br />Further analysis will be conducted during future investigations to evaluate <br />whether or not any of the discontinuity sets (F-1 through F-3) occur in the same <br />location simultaneously, or if the localized faulting has resuRed in "structural <br />blocka" that have created regions in which the foliation planes occur separately. <br />Theso questions will continue to be addressed as more data is collected. <br />' Relative to each of the quarry walls, the north walls with an overall slope angle of <br />approximately 35° are currently stable; and as stated in previous reports the slide <br />' that occurred on the northeast wall has shown no signs of continued movement <br />since the steepness of the wall slope was modified in 1999. Based on data <br />' collected from boreholes in the 2003 geotechnical investigation, a number of <br />relatively shallow foliation surfaces will be encountered below the current main <br />' pit elevation of 6,340 feet, and the north walls should be monitored closely as the <br />-2- <br />