2010-02-02_REPORT - M1973021 (2)

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2.0 2009 MINING SUMMARY 2.1 North Quarry Mining in the North Quarry was completed as of December, 2007. The North Quarry is currently being used as a raw water reservoir by the Town of Morrison and Aggregate Industries. Activity in the North Quarry has been limited to slope stabilization of the fill slopes on the west side of the quarry. The work involved the hauling of material from the west slopes to the north repository. The slopes and repository were seeded after the work. As such, no major rock disturbance or mining occurred in the North Quarry in 2009. Figure 2 is a photograph of the completed Quarry area, showing the stabilized north fill slope and the north repository area. Figure 3 shows the Morrison Reservoir. 2.2 Central Quarry Mining in the Central Quarry was completed as of December, 2001. As such, no major rock disturbance or mining occurred in the Central Quarry in 2009. In 2009, water formerly stored in the Central Quarry, was pumped to the North Quarry and the Central Quarry was partially backfilled with stripped material from the South Quarry as shown in Figure 4. 2.3 South Quarry Mining in the South Quarry continued in 2009, expanding the pit to the west, south and east. Material was mined from approximate elevations 7000 to 6700 feet above MSL utilizing a slope configuration of 1/2:1 (H:V) consisting of 60-foot highwalls and 40-foot benches. Four highwall and bench areas were open and accessible at the time of the field work. The total highwall height increased from 280 feet in December, 2008 to 340 feet in December, 2009. The South Quarry area mined in 2009 is approximately shown on Figure 5. Figures 6 through 9 are photo documentaries of the highwalls surveyed for this report. In addition, a haul road was constructed on the west part of the active mine to access future mining areas. 3.0 FIELD DATA At locations exposed by mining in 2009, rock mass data including joint orientation and dip, foliation orientation and dip, rock mass rating (RMR) classification estimates, and unusual rock features such as shear zones, persistent intrusions, or weak rock zones, were documented. Orientations were collected using a Brunton compass (10 degree east magnetic declination) and recorded using the right hand rule. All orientation measurements were estimated from a safe distance back from the highwalls due to active mining activity and rockfall safety concerns and as requested by Al. -2- Morrison Quarry Annual Report 2009 February 2010 P:\23514\133-23514-10003\Deliverables\Deliv-01 -Annual Report\Annual_Report_2009_Geotech, 1-25-10.doc