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

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A ' Preliminary Sand and Gravel Mineral Evaluation Terracon 29 Acre Parcel -East of Balsam Avenue Greeley, Weld County, Colorado Project No. 20015242 ' Field Exploration A total of 7 test borings were drilled at the site during month of November of 2001. Terracon ' drilled 3 test borings, (identified as Test Boring Nos. 1, 2, and 3 shown on the enclosed Site Plan, Figure 3) on November 5 and 6, 2001 to approximate depths of 75 to 90-feet below existing site grades. These 3 borings were advanced with a CME 75 truck-mounted drilling rig, utilizing 4-1/4-inch inside diameter hollow stem augers. ' After completing the first three borings, the client elected to obtain a specialized drill rig capable of extending the test borings to the bedrock stratum by means of air rotary equipment. An air rotary rig from Layne-Western of Denver, Colorado, with assistance from the clients conducted the remaining 4 test borings, (identified as Test Boring Nos. B-1, B-2, B-3, and B-4 shown on the enclosed Site Plan, Figure 3) and logged the depths of the soil stratification to bedrock. These test borings extended to approximate depths of 82 to 90-feet below existing site grades. The borings were located in the field by measurements from existing site features at the direction of Doug and Dan+vin Derr. After completing the related field services, the client hired a land surveyor, which provided the appropriate boring locations and elevations as presented in this report. Continuous lithologic logs of each boring drilled by Terracon (Test Boring Nos. 1, 2, and 3) were recorded by the engineering geologist during the drilling operations. At selected intervals, samples of the subsurtace materials from these test borings were taken by driving asplit-spoon sampler. Auger cutting samples from the air rotary Layne-Western Test Boring Nos. B-1, B-2, B-3, and B-4, were obtained by the client at selected intervals and were delivered to Temacon's .Greeley office for further evaluation and laboratory testing. Penetration resistance measurements were obtained by driving the split-spoon into the ' subsurface materials with a 140-pound hammer falling 30 inches for the Terracon test borings. These penetration resistance values are a useful index to the consistency, relative density or hardness of the materials encountered. ' Groundwater measurements were made in Test Boring Nos. 1, 2, and 3 at the time of the initial site exploratian. Groundwater measurements were not recorded or provided to Terracon for the Layne-Western borings. prior to preparation of this report. Laboratory Testing All samples retrieved during the field exploration for Test Boring Nos. 1, 2, and 3 and the composite samples collected by the client for the Layne-Western borings were returned to the laboratory for observation by the project geotechnical engineer, arid were classified in 2