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• Brierley And Associates(2006)Geotechnical Slope Stability and Geological Report—This report tends to reflect an improvement on the earlier Fox Report but is subject to many of the same limitations, in that the author was forced to draw many of their concludes given only having he limited fresh faces exposed in the active workings, such as existed at the time of the report, and having a higher percentage of poorer quality, lower RQD value materials in the naturally-spalled weathered materials collected from the toe of the slope of the broader joint sets, somewhat opened about 14 to 36%from weathering as they are closer to the weathered zonae and within the largely biotite rich migmaticitic mafic deposit,the fine grained movement heavy gneiss tends to weather at a slightly faster rate than the more pegmatite felsic rich later injections of quartz and lighter mineralization rich post injection intrusions into the complex contact area. This material occurs with a much higher frequency approaching the largely vertical-sub vertical contact one, intruding in roughly hemispherical bubble shaped injection that cool at a slower rate,given the higher percentages of quartz in the liquid,giving raze to a higher percentage (over 60%)of K and Na-rich twinned feldspar crystals and an estimated 42 to 57%of striking well developed lightly stained quartz crystals. Biotite rarely appears even within the native Idaho Springs Formation and is largely driven out of the deposit at this point. The joint sets rotate from being somewhat oblique to one another immediately parallel subparallel to the existing highwall and ted to be more cubic and at 90 degrees to one another with the primary joint set trending North North East at between 69 degrees and 89 degrees and the second set largely horizontal to sub horizontal.There is increasing levels of situation in the joint sets as the deposit trends through towards the west in general and slightly more to the South. All this material has been mined out and this information is based on the direct information by experience of the Operator. There is remarkably little deleterious materials and no alteration to speak of through the bulk of the advancing deposit to the east of the existing highwall.This makes sense since observations indicate that due to the slower cooling rates of the largely felsic material, we are seeing classic example of a lighter,typically very hard,somewhat abrasive, light pink or rose colored hue,free of the feldspathc alterations frequently seen elsewhere in norther exposures in local quarries. The reason that there is no alteration is that tis deposit is also remarkably free of any structure and thus there is none of the hydrothermal alterations that chiefly characterize the Pikes Peak formation elsewhere,giving rise to the characteristic decomposed granite. No this deposit is about as clean and unadulterated as it gets,yielding some breath taking 21 to 54 values on the LA abrasion index at the peak of the deposit T nearest structure observed is by reference (CDOT Geotechnical reports 2009,Yen and Assoc., CDOT NH2854-109 Preconstruction geotechnical repot).This is defined as a shear zone trending vertical to sub vertical and essentially following the alignment of the 285 corridor.The pint of contact exposure is immediately under the Southbound lane of SH285 trending east-west roughly and the shear zone is associated with much softer substrate, largely Qu alluvium,some past depositional alteration in the zone immediately adjacent to the structure up to a n offset distance approaching 18 feet in either direction with a zone of influence some 67 to 90 feet in the aggregate We further note that there is no apparent structure exposed in advance of nor by the advancing highwall. Any foliated lithology, where this is still chiefly present in the Idaho Springs Formation, is superficial or non-occurring through the complex undulating folds of the complex interface between the two lithology's, and the interstitial matrix is sound, dense and relatively neutral or