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-2- <br />EARTH MATERIALS NEEDED FOR HIGHWAY 9 UPGRADE <br />It is our understanding that the proposed upgrade of Highway 9 will require earth <br />materials for use as road base and asphalt aggregate. The Colorado Department of <br />Transportation's design estimate is about 200,000 tons of Class 3 road base, about <br />100,000 tons of Class 6 road base and about 95,000 tons of SX asphalt aggregate. <br />POTENTIAL BORROW SITE <br />The potential borrow site evaluated by this study is on a high -level river terrace located <br />about three miles south of the ranch headquarters as shown on Figure 1. The potential <br />borrow site (map unit Qtl' on Figures 2 and 3) covers about 128 acres and is located about <br />80 feet above the Blue River. An existing seven acre borrow pit is located on the same <br />high -level terrace to the north of the potential new borrow site as shown by map unit ebp <br />on Figures 2 and 3. The high -level terrace surface at the potential new borrow site is <br />nearly level with a slope of about 2 percent down to the west. A very steep (65 percent) <br />terrace escarpment borders the terrace surface on the north, south and west. The preferred <br />location for the new borrow pit from the ranch owner's perspective is in the southern part <br />of the high -level terrace as shown by map unit pnbp on Figures 2 and 3. The Blue River <br />alluvium that underlies the high -level terrace is a late Pleistocene -age glacial outwash <br />deposit that is probably around 10,000 to 35,000 years old. The Blue River alluvium on <br />the terrace overlies the late Cretaceous -age, Pierre Shale (Tweto, 1973). Bedding in the <br />shale strikes to the northwest and dips about 10 degrees to the southwest (Tweto, 1973). <br />FIELD OBSERVATIONS <br />During our field reconnaissance on August 26, 2014 the depth to shale below the high - <br />level terrace surface was measured in several places along the terrace escarpments at the <br />locations shown on Figures 2 and 3. These measurements show that the shale lies <br />between about 10 and 35 feet below the terrace surface at the observation sites. At this <br />same time we also measured the soil profile in the existing borrow pit that has been <br />Job No. 114 342A C 'tech <br />