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<br />Aggregate Industries Morrison Quarry GEI Consultants, Inc. <br />Geotechnical Addendum, 2016 Annual Report 4 January 2017 <br />3. Field Data <br />Rock mass characteristics were documented at locations exposed during 2016 mining <br />operations. Items documented include joint and foliation orientation and dip, highwall trends, <br />and rock mass rating (RMR) classification estimates. In addition, unusual rock features <br />exposed in the highwalls such as shear zones, intrusions, adversely dipping foliation, and <br />areas of potential instability were documented. <br />Dip and orientation data was gathered using a Brunton compass with a 9 degree east <br />magnetic declination and measurements were taken using the right hand rule. Measurements <br />were estimated a safe distance from the highwalls and excavated areas to address safety <br />considerations at the request of AI and GEI personnel. <br />RMR classification is determined from highwall conditions noted with the following <br />parameters and associated point scales (numbers in parentheses): <br /> Estimated Strength of Intact Rock Material <br /> Very High (15 points): >36,260 psi <br /> High (12): 14,500 – 36,260 psi <br /> Medium High (7): 7,250 – 14,500 psi <br /> Moderate (4): 3,625 – 7,250 psi <br /> Low (2): 725 – 3,625 psi <br /> Very Low (1): 145 – 725 psi <br /> Estimated Drill Core Quality (RQD) <br /> Excellent Quality (20 points): 90 – 100% <br /> Good Quality (17): 75 – 90% <br /> Fair Quality (13): 50 – 75% <br /> Poor Quality (8): 25 – 50% <br /> Very Poor Quality (3): <25% <br /> Spacing of Discontinuities <br /> Very Wide (20 points): >6.5 feet <br /> Wide (15): 2 – 6.5 feet <br /> Moderate (10): 8 – 24 inches <br /> Close (8): 2.4 – 8 inches <br /> Very Close (5): <2.4 inches