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rock disturbance or mining occurred in the North Quarry in 2008. Figure 2 is a photograph of <br />the completed Quarry area. <br />2.2 CentralOuarry <br />Mining in the Central Quarry was completed as of December, 2001. The Central Quarry is <br />currently being used as a raw water reservoir for the use of the Town of Morrison and <br />Aggregate Industries with an approximate water level elevation of 6430 feet above MSL at the <br />time of this report. As such, no major rock disturbance or mining occurred in the Central <br />Quarry in 2008. Grading of the haul road which crosses the Central Quarry to access the South <br />Quarry was performed in 2008. <br />2.3 South Quarry <br />Mining in the South Quarry continued in 2008, expanding the pit to the north and east. <br />Material was mined from approximately elevations 7000 to 6760 feet above MSL utilizing a <br />slope configuration of/z:1 (H:V) consisting of 60 foot highwalls and 40 foot benches. <br />Approximately 3 highwall and bench areas were open and accessible at the time of the field <br />work. The total highwall height increased from 40 feet in December, 2007 to 280 feet in <br />December, 2008 (5 total benches, one 40 foot high and four 60 foot high). The South Quarry <br />area mined in 2008 is approximately shown on Figure 3. Figures 4, 5, 6, and 7 are photo <br />documentaries of the highwalls surveyed for this report. In addition, a haul road was <br />constructed to access the mining areas. <br />3.0 FIELD DATA <br />At areas exposed by mining in 2008, rock mass data including joint orientation and dip, <br />foliation orientation and dip, rock mass rating (RMR) classification estimates, and unusual <br />rock features such as shear zones, persistent intrusions, or weak rock zones, were documented. <br />Orientations were collected using a Brunton compass (10 degree east magnetic declination) <br />and recorded using the right hand rule. All orientation measurements were estimated from a <br />safe distance back from the highwalls due to active mining activity and as requested by Al. <br />3.1 North Ouarry <br />No mining occurred in the North Quarry in 2008 and thus no new orientation data related to <br />mining activity was collected. Observations of the existing highwalls and benches were <br />conducted and compared with previous observations. Localized instabilities were observed <br />and local raveling of the rock faces has occurred. This raveling is likely due to adverse <br />jointing, rock weakened by alteration, and/or weathering actions such as freeze thaw cycles. <br />Blocks loosened in this fashion are generally small (less than approximately 1 '/2 feet in <br />diameter) and collect on the benches. No major rock disturbances occurred in the North Quarry <br />in 2008. <br />W Minor seepage was observed near the bottom elevation of the North Quarry. Per Al records, <br />.& 8,856,000 gallons of water (27 acre-feet) were pumped from the North Quarry during 2008. <br />Pumping was discontinued in December of 2008. <br />Ao' -2- <br />Morrison Quarry Annual Report 2008 February 2009 <br />F:\3919_038\Annual_Report _2008\Geotech_Report _2008\Annual_Report _2008_Geotech.doc