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Mr,Jeff Gregg <br /> January 5,2006 <br /> Page 2 <br /> CIVIL RES�URCES,LLC <br /> GEOTECHNICAL CONDITIONS <br /> The mine site is located on a terrace of the South Platte River. Review of regional geologic mapping (Trimble and <br /> Machette, 1979) indicates the site subsurface materials consist of Post-Piney Creek Alluvium most likely overlying <br /> sandstone and claystone bedrock of the Denver Formation. Exploratory borings drilled by Rocky Mountain Consultants <br /> (RMC, 2000)primarily along the eastern portion of the site, encountered approximately two to four feet of overburden <br /> topsoil and clay soils overlying approximately 22 to 41 feet of sand and gravel on top of primarily claystone bedrock. <br /> Locations of the property extents and boring locations are shown on Figure 2. The bedrock depths ranged from <br /> approximately 26 feet to 43 feet below the ground surface. There was sufficient information from the bore logs from TH- <br /> 3, TH-6, and TH-26(Figure 2)to estimate the attitude of the bedrock plane using the proportional three-point method. <br /> The calculated attitude of the formation at this site was N19 degrees W, dipping at 1 degree to the northeast. <br /> From a geotechnical standpoint,the sand and gravel will form the most of the mine slopes, These soils are generally <br /> strong and stable, particularly when dewatered. <br /> SITE GROUNDN✓ATER <br /> Civil Resources conservatively modeled the groundwater at just below the clayey overburden, four feet below the ground <br /> surface, based on the Rocky Mountain Consultants geotechnical exploration. <br /> STRUCTURES WITH 200 FEET OF DISTURBED AREAS <br /> The known,permanent,man-made structures within 200 feet of the proposed mine area that are not owned by Halldr,vin <br /> Corporation are listed below: <br /> 0,1CR 2 3.5 iiAlaLiwrn uvunuall), <br /> • WCR 23.75(northern boundary), <br /> • WC 2/Baseline Road/1681h Ave (southern boundary), <br /> • Mountain View Water Users Association water pipeline(south and west, <br /> • Gas well and underground gas pipelines (south and west), <br /> • Underground telephone utilities(south and west), <br /> • Overhead power utilities(south and west), <br /> • Valerie and Robert Parker residence,outbuildings,fence and well(west), <br /> • Randy Kirkpatrick residence,outbuildings,fence and well (west), <br /> • Jose and Maria Lujan residence, outbuildings, fence and well(west), <br /> • Lot Holdings, LLC Residences, outbuildings,fence and wells(west and south), <br /> • Bestway Concrete Batch Plant(east), <br /> • Sakata Farms well (southwest), <br /> EXISTING EASEMENTS <br /> It is our understanding that the following easements exist at the site: <br /> • Mountain View Water Users Association easement to the south and west. <br /> 0 Railroad easement to the west-abandoned <br />