2008-03-25_PERMIT FILE - M2008017 (2)

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A 1 1 Preliminary Sand and Gravel Mineral Evaluation 29 Acre Parcel -East of Balsam Avenue Greeley, Weld County, Colorado Project No. 20015242 7erracon accordance with the Unified Soil Classification System described in Appendix C. Samples of bedrock were classified in accordance with the general notes for Bedrock Classification. At that time, the field descriptions were confirmed or modified as necessary and an applicable laboratory testing program was formulated to determine engineering properties of the subsurface materials. Boring logs were prepared and are presented in Appendix A. Selected soil samples were tested for the following engineering properties: • Water content • Grain size distribution f A Laboratory test results are presented. in Appendix B..All laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards. SITE CONDITIONS The site is presently utilized, as agricultural land and/or grazing land as well as by the Oil Industry. The site is relatively flat exhibiting positive surface drainage in the southeast direction. South of the site is vacant; undisturbed land typical in terrain as the subject site. West of the site is Balsam Avenue and north id the Eaton Ditch. The Cache La Poudre River is situated approximately 1-mile south of the site. An abandoned gravel pit is located directly west of the subject site vn the west side of Balsam Avenue. SUBSURFACE CONDITIONS Geology The.. proposed area is located within the Colorado Piedmont section of the Great Plains physiographic province. The Colorado Piedmont, formed during Late Tertiary and Early Quaternary time (approximately 2,000,000 years ago), is a broad, erosional trench, which separates the Southern Rocky Mountains from the High Plains. Structurally, the site lies along the western flank of the Denver Basin. During the Late Mesozoic and Early Cenozoic Periods (approximately 70,000,000 years ago), intense tectonic activity occurred, causing the uplifting of the Front Range and associated downwarping of the Denver Basin to the east. Relatively flat uplands and broad valleys characterize the present-day topography of the Colorado Piedmont in this region. The site is underlain by the Cretaceous Pierre Formation at approximate depths of 68 to greater than 90-feet below existing site grades. The bedrock is 3 ,.