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Mr. Jeff Gregg January 5,2006 Page 2 GEOTECHNICAL CONDITIONS ~~ CIVIL RES'JU RCES,LLC The mine site is located on a terrace of the South Platte River. Review of regional geologic mapping (Trimble and Machette, 1979) indicates the site subsurface materials consist of Post-Piney Creek Alluvium most likely overlying sandstone and claystone bedrock of the Denver Formation. Exploratory borings drilled by Rocky Mountain Consultants (RMC, 2000) primarily along the eastern portion of the site, encountered approximately two to four feet of overburden topsoil and clay soils overlying approximately 22 to 41 feet of sand and gravel on top of primarily claystone bedrock. Locations of the property extents and boring locations are shown on Figure 2. The bedrock depths ranged from approximately 26 feet to 43 feet below the ground surface. There was sufficient information from the bore logs from TH- 3, TH-6, and TH-26 (Figure 2) to estimate the attitude of the bedrock plane using the proportional three-point method. The calculated attitude of the formation at this site was N19 degrees W, dipping at i degree to the northeast. From a geotechnical standpoint, the sand and gravel will form the most of the mine slopes. These soils are generally strong and stable, particularly when dewatered. Civil Resources conservatively modeled the groundwater at just below the clayey overburden, four feet below the ground surface, based on the Rocky Mountain Consultants geotechnical exploration. STRUCTURES WITH 200 FEET OF DISTURBED AREAS The known, permanent, man-made structures within 200 feet of the proposed mine area that are not owned by Hall-Irwin Corporation are listed below: • WCR 23.5 (western boundary), • WCR 23.75 (northern boundary), • WCR 2/Baseline Road/168~ Ave (southern boundary), • Mountain View Water Users Association water pipeline (south and west) • Gas well and underground gas pipelines (south and west), Underground telephone utilities(south and west), • Overhead power utilities {south and west), • Valerie and Robert Parker residence, outbuildings, fence and well (west), • Randy Kirkpatrick residence, outbuildings, fence and well {west), • Jose antl Maria Lujan residence, outbuildings, fence and well (west), • Lot Holdings, LLC Residences, outbuildings, fence and wells (west and south), Bestway Concrete Batch Plant (east), • Sakata Farms well (southwest), It is our understanding that the following easements exist at the site: • Mountain View Water Users Association easement to the south and west. • Railroad easement to the west -abandoned