2001 Geotechnical Evaluation Report

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RVC Homes Project BABX-01-0124 April 12, 2001 Page 3 From a depth of about 19 feet to the boring termination depth of 30 1/2-feet,the boring encountered clayey sand and sandy lean clay glacial till. N-values in the glacial till ranged from 10 to 16 BPF, indicating the sandy lean clay to be in a rather stiff consistency and the clayey sand to be medium dense to loose. Boring ST-2, located near the northeast proposed building area, encountered about 11 feet of fill over a 2-foot thick layer of peat. The fill is a mixture of lean clay with sand,topsoil, silty sand, and clayey sand. N-values in the fill average about 3 BPF, indicating it is poorly compacted. Below the fill and peat, the boring encountered a variety of slopewash and lacustrine soils to a depth of about 33 feet. These soils consist of silty sand, organic silt and organic clay. N-values range from weight of hammer to 2 BPF, indicating these soils are very loose or very soft. Below the slopewash and lacustrine soils, the boring encountered glacial till to the borings termination depth of 60 1/2-feet. The glacial till consist of clayey sand and lean clay with N-values ranging from 5 BPF at 40 feet and gradually increased to 18 BPF at 60 feet. Large gravel, cobbles or boulders are also common to glacial till soils. B.3. Groundwater When groundwater was encountered during drilling or sampling its depth was measured within the hollow-stem auger. Water level measurements were also made immediately after the auger was removed. The borings were then backfilled with quickset grout in Boring ST-2. Groundwater was not observed in Boring ST-1. Groundwater was encountered during drilling or sampling at an elevation of about 925 in Boring ST-2 or at an elevation of about 922 1/2 after removal of the hollow-stem auger. Because of the relatively impermeable nature of the soils encountered, it is our opinion the measured water level after the auger was removed is below the true static groundwater level. It is our opinion the actual static groundwater elevation lies somewhere above or within the peat zone or at an elevation between 929 and 924 1/2. It is likely the groundwater level is closely related to the level of Lake Minnetonka, which we understand is now 929. This corresponds with the groundwater elevations observed in the borings taken at 1074 Wildhurst Trial. Annual and seasonal fluctuations of the groundwater level should be anticipated. C. Analyses and Recommendations C.1. Proposed Construction We understand the proposed house is a single-family residential structure with a walkout basement to the east. At this time, the house location is shown on the attached boring location sketch. However, we understand the house location may be moved closer to Wildhurst Trail. We assume the site grades will