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1. GEOTECHNICAL REPORT,SLOPE STABILITY ANALYSIS AND ENGINEERING REPORT ON HIGHWALL <br /> The Brierley Report(2005) described the site geology as per the original description from the Fox Report <br /> prepared by F.M. Fox Associates, Inc. (1878) (1)at the time of original DMG permitting in 1978. A copy <br /> of this document is included as Attachment A for reference. <br /> The colluvium described in the Fox Report and Brierley Report no longer exists within the quarry in the <br /> active mining area.This has been harvested or mined and 100%of the extracted materials were used. <br /> The Precambrian bedrock, known commonly locally as the Pikes Peak and Idaho Springs Formation is <br /> exposed, presenting a clean, hard tight principally mafic formation,free from discontinuities or any type <br /> of structural abnormality, alternation,significant moralization or heat alteration (shear) zone. <br /> There is a thin veneer of the hillside colluvium (up too several feet), to the East and South of the mining <br /> property on the adjacent parcel The colluvium is Pleistocene to Holocene (Recent) Pleistocene alluvium <br /> reportedly exists at the extreme western edge of the site, but is not of interest because it is west of the <br /> active mining operations. <br /> Mining method is largely a standard block extraction technique with little or no blending required due to <br /> the homogeneous nature of the site <br /> Mining takes place typically by blasting in increments of 60,000 to 100,000 tons per shot in a <br /> predetermined pattern given the proximity of the shot to any surface weathering or the highwall.The <br /> shot has exhibited a high level of efficiency and a low relative powder factor. Non el delays are typically <br /> utilized for each shot. <br /> Blasting takes place to maximize removals efficiently however in order to accommodate the 3D renders <br /> simulation and other submitted at time of approvals in front of the Board and to the PUD Special Use <br /> Application (County)some `offset' blasting ND other staggering or decoupling techniques allow for the <br /> highwall to conform to a more softened appearance arising from the irregular shot pattern proximal to <br /> the final pit limits. <br /> The rational for this is that we can definitively indicate that the structural components of the original <br /> engineered intent of the configuration are not impaired nor abridged bit these modifications, and as a <br /> result the highwall maintains the same engineering values and characteristics preventing a toppling or <br /> overturning moment from arising, but he finished appearance of the highwall is slightly more irregular <br /> than a conventional highwall in appearance only,thus offering a more natural appearance,encouraging <br /> and offering nesting habitat. <br /> The Fox report appears to be based on the Reconnaissance Geologic Map of the Pine Quadrangle <br /> (1:24,000) (2). A copy of an excerpt from that map showing the project site area is included as <br /> Attachment B to this report. The geologic information included in this reference confirms bedrock <br /> consisting of migmatitic biotite gneiss with biotite schist,granitic gneiss and amphibolite. General <br /> geologic structure mapped near the quarry includes north to northwesterly striking, easterly to <br /> northeasterly dipping foliation and metamorphic compositional layering generally parallel to the <br />