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3. Laboratory Analysis <br /> 3.1 Pre-2017 Laboratory Analyses <br /> Laboratory testing was performed on samples collected during the 2005 Lyman Henn <br /> subsurface investigation to evaluate samples for L.A. Abrasion. <br /> Laboratory testing was performed on samples collected during the 2007 Al subsurface <br /> investigation to evaluate samples for Micro Deval and L.A. Abrasion. <br /> Laboratory testing was performed on samples collected during the 2007-2008 GEI <br /> subsurface investigation to evaluated samples for Micro Deval and L.A. Abrasion. <br /> Laboratory testing was performed on samples collected during the 2011 Tetra Tech <br /> subsurface investigation including moisture density relationships, unconfined compressive <br /> strength with Young's Modulus, direct shear on joints and saw cuts, and slake durability. <br /> Tetra Tech concluded that the results of the laboratory testing program indicated that rock <br /> mass was typically very strong, experienced strength decreases in locally weathered zones, <br /> where it was classified as strong. Areas near the original ground surface or near faults were <br /> found to be classified as medium strong to weathered. Mafic intrusions were considered to be <br /> medium strong to weathered. Due to results of the slake durability testing, Tetra Tech found <br /> that the mafic dikes were susceptible to wet/dry cycles which could result in more <br /> weathering. <br /> 3.2 2017 Laboratory Analysis <br /> GEI reviewed rock cores and developed laboratory test assignments on selected samples <br /> collected by Al in 2017. Laboratory testing included direct shear on natural joints and saw <br /> cut samples. Laboratory test results are presented in Appendix A. <br /> Direct shear testing on natural fractures within the granitic or biotitic gneisses resulted in <br /> cohesion values ranging from 0 to 151.5 pounds per square inch(psi), and phi ((p) angles <br /> ranging from 14.3 to 47.7 degrees. Direct shear testing on saw cut samples within the granitic <br /> or biotitic gneisses resulted in cohesion values ranging from 3.8 to 20.3 psi and cp angles <br /> ranging from 18.6 to 25.2 degrees. Direct shear testing on natural fractures within the <br /> sillimanitic gneiss resulted in cohesion values ranging from 0 to 63.6 psi and cp angles <br /> ranging from 15.3 to 27.7 degrees. Direct shear testing on saw cut samples within the granitic <br /> sillimanitic gneiss resulted a cohesion value of 29.1 psi and cp angle of 3.8 degrees. A <br /> summary of the test results is presented in Table 2. <br /> Aggregate Industries Morrison Quarry GEI Consultants, Inc. <br /> South Quarry Highwall Design Technical Revision 11 August 2017 <br />