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1.0 Introduction LACHEL & Associates, Inc. (L&A), Golden, Colorado has prepared this independent annual structural geology evaluation for the Specification Aggregates (Spec-Agg) Quarry in Golden, Colorado for 2004. This study was conducted at the request of Lafarge West, Inc., owner of the quarry, as a requirement for State of Colorado, Permit number M-74004. The structural evaluation includes observations and measurements from the quarry that have been obtained annually by L&A staff over the past seven years and from results of the geotechnical investigation directed by L&A in 2003. The purpose of the annual evaluation is to monitor the impact of the structural geologic features on pit wall stability as mining progresses. The measurements, observations, and structural analyses have been performed by L&A geologists and engineers, and are applicable to the quarry at the time of the data was obtained (February 2004). More specifically, the goals of this study are as follows: • Map and photograph geologic discontinuities along each quarry wall and utilize the new data in validating and updating the existing structural geology database; • Analyze the new data relative to the existing data in order to verify and/or modify existing conclusions, and to investigate possible emerging trends; • Review and characterize the existing stability conditions at the quarry relative to the current mine plan; • Locate and document changes in groundwater conditions; • Locate and document any obvious slope instabilities. 2.0 Summary and Conclusions The results of the structural geologic evaluation of the Spec-Agg Quarry, which included field observations, geologic mapping, and stereographic analysis of structural geology data, indicate that the current quarry configuration is stable under the existing conditions and current rock mass assumptions. The stability of each of the slopes is enhanced by the absence of significant hydrostatic -~-