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Report of Geotechnical Exploration and Review Fox Street Improvements, Orono, Minnesota AMERICAN July 29, 2016 ENGINEERING Report No. 20-14448 TESTING, INC. Page 3 of 12 5.0 SITE CONDITIONS 5.1 Topography and Surface Conditions Fox Street is a two-lane bituminous roadway without curb and gutter. The topography along the road is rolling through residential areas with trees and wetlands. The road crosses Long Lake Creek just west of Brown Road South. Overall, the pavement surface is in poor condition with evidence of patching at points throughout the route. There is also random pavement cracking, transverse and longitudinal cracking, and unevenness of the pavements. 5.2 Pavement and Base Thickness The bituminous pavement thickness measured in the boreholes ranged from 4.5 to 18.75 inches thick. The thicker bituminous measurements generally were encountered east of Brown Road South in areas where the roadway is adjacent to wetlands. The variable thickness indicates that localized overlays or full depth patches have likely occurred in the past to address pavement distress or settlement. Below the bituminous pavement, we encountered an aggregate base-like material at 16 of the boring locations consisting of silty sand with gravel, sand with silt & gravel, and crushed limestone. The thickness of these layers generally ranged from 2 to 18 inches. At Boring 10, the sand with silt & gravel layer extended from ½ to 4½ feet below grade. Reference should be made to the boring logs for additional information. 5.3 Subgrade Soils Below the pavement section, the borings encountered fill or possible fill to depths of ¾ to 11 feet below grade overlying buried topsoil, mixed alluvium, fine alluvium, and glacial till. Naturally- deposited silty sand (coarse alluvium) was encountered below the fill soils at Boring No. 24. The fill and naturally-deposited soils generally consisted of lean clay, sandy lean clay, and clayey sand with occasional zones of silty sand. Below the fill at Boring Nos. 11, 12, and 19 through 22, the borings encountered swamp deposits consisting of peat and organic clay as shallow as 4 to 7 feet below grade. The borings extended through the swamp deposited soils to the underlying lean clay, sandy lean clay, and clayey sand