6.3. SR 02-07-2005 - Laserfiche WebLink

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I I I City of Elk River Project BN-04-06875 December 8, 2004 Page 7 I I with the embanlanent construction for so long as the weather will permit with the understanding that the additional costs involved shall be borne by the contractor. The fr"ozen soil should be pulverized or wasted and replaced with other suitable soil, as may be necessary to construct the embankments as specified. I I E. Procedures I E.1. Drilling and Sampling We performed the penetration test borings on November 1, 2004, with a truck -mounted core and auger drill equipped with 3 I/4-inch inside diameter hollow-stem a,uger. Sampling for the borings was conducted in general accordance with ASTM D 1586, "Penetration Test and Split- Barrel Sampling of Soils. " We advanced the boreholes with the hollow-stem auger to the desired test depth. A I40-pound hammer falling 30 inches was then used to drive the standard 2-inch split-barrel sampler a total penetration of 1 1/2 feet below the tip of the hollow-stem auger. The blows for the last foot of penetration were recorded and are an index of soil strength characteristics. Samples were taken at 2 I/2-foot vertical intervals to the termination depths of the borings. A representative portion of each sample was then sealed in a glass jar. I I I I E.2. Soil Classifications The drill crew chief visually and manually classified the soils encountered in the borings in accordance with ASTM D 2488, "Description and Identification of Soils (Visual-Manual Procedures)." A summary of the ASTM classification system is included in the Appendix. All samples were then returned to our laboratory for review of the field classifications by a geotechnical engineer. Representative samples will remain in our Blaine office for a period of 60 days to be available for your examination. These samples will then be discarded unless we are notified in writing to retain them longer. I I I I E.3. Groundwater Observations Immediately after taking the final samples in the bottoms of the borings, the crew probed the holes through the hollow-stem auger to check for the presence of groundwater. Immediately after withdrawal of the auger, the holes were again probed and the depths to water or cave-ins were noted The borings were then immediately backfilled. I I I