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Report of Geotechnical Exploration <br />North Arm Bay Boat Launch; Mound, MN <br />April 10, 2023 <br />AET Report No. P-0016964 <br />AAMEMICAN <br />The logs contain information concerning soil layering, soil classification, geologic origins, and <br />moisture condition. Relative density description or consistency is noted for the natural soils, <br />which is based on the standard penetration resistance (N-value). <br />The boring locations are shown on Figure 1 in Appendix A. The borings were located and staked <br />in the field by IMO personnel. Final boring location coordinates and elevations were collected by <br />AET personnel using a handheld GPS with sub -meter accuracy. <br />4.2 Laboratory Testing <br />In addition to the visual -manual classification of the soil samples, we performed moisture content <br />and sieve analysis tests on select samples. The test results appear in Appendix A on the <br />individual boring logs adjacent to the samples upon which they were performed and/or attached <br />data sheets. <br />5.0 SITE CONDITIONS <br />5.1 Surface Observations <br />Site surface conditions are a bituminous paved parking lot with sod and vegetation -covered <br />areas on the perimeter. At the time of drilling, areas of the site were being used for excess snow <br />storage. The site topography is relatively flat with a gentle slope downward north to the lake <br />shore. The fill soils on site were found to be frozen to a depth of 4 feet below grade, which does <br />not allow our drilling team to collect reliable N-value blow counts during the sample collection <br />process, so we obtained auger samples in the upper 4 feet as noted on the logs. <br />5.2 Subsurface Soils/Geology <br />The subsurface soils mostly consisted of partially frozen fill soils overlying layers of swamp <br />deposits and coarse alluvium to the boring termination depths of 20 to 21'/2 feet below grade. <br />The fill depth is about 12 feet below existing grades and consists of lean clay with sand, sandy <br />lean clay, clayey sand, and silty sand. Below the bituminous pavement a layer of apparent <br />aggerate base layer consisting of silty sands with varying amounts of gravel was present in all <br />four of the borings. No historical pavement data was available to verify this assessment. <br />The coarse alluvium in Boring B-2 consists of loose silty sand with organic fines and was <br />observed below the sapric peat to the boring termination depth of 21'/2 feet. All other borings <br />terminated in swamp -deposited soils. <br />Page 2 of 5 <br />121 <br />