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� 6 � � � <br /> A field log of each boring was prepared by the HGTS drill crew. The logs contained visual <br /> classifications of the soil materials encountered during drilling, as well as the driller's <br /> interpretation of the subsurface conditions between samples and water observation notes. <br /> The final boring logs included with this report represent an interpretation of the field logs <br /> and include modifications based on visual/manual method observation of the samples. <br /> The soil boring logs, general terminology for soil description and identification, and <br /> classi�ication of soils for engineering purposes are also included in the appendix. The soil <br /> boring logs identify and describe the materials enrnuntered, the relative density or <br /> consistency based on the Standazd Penetration resistance(N-value,"blows per foot")and <br /> groundwater observations. <br /> The strata changes were inferred from the changes in the samples and auger cutkings. The <br /> depths shown as changes between strata are only approximate. The changes are likely <br /> transitions,variations can occur beyond the location of the boring. <br /> 3.0 RESULTS <br /> 3.1 Soil Conditions <br /> The soil borings�countered about 1 foot of topsoil at the surface.The topsoil consisted <br /> of sandy lean clay that was black in color. <br /> Beneath the topsoil,the borings encountered native alluvial lean clay soils that extended <br /> to around 4 feet below the ground surface. Penetration resistance values (N-values), <br /> shown as blows per foot(bp�on the boring logs,of 8 blows per foot(bp fl were recorded <br /> in the lean clays which indicate a medium consistency. <br /> Underlying the topsoil and alluvial clay soils,the soil borings encountered glacial till soils <br /> that extended to the boring termination depths of about 40 feet. The glacial till soils <br /> consisted mainly of clayey sand, with upper layers of sandy lean clays and lean clays <br /> encountered at boring SB-1. N-values of 10 to 26 bpf were recorded in the glacial till soils. <br /> These values indicate the clayey sands had a medium dense relative density with upper <br /> loose zones while the sandy lean clays/lean clays had a stiff consistency. <br /> 3.2 Groundwater <br /> Groundwater was encountered in both soil borings after drilling between depths of about <br /> 31 1/z to 34 feet which correspond to elevations of about 936 to 938. Water levels were <br /> measured on the dates as noted on the boring logs and the period of water level <br /> observations was relatively short. Given the cohesive nature of the glacial till soils <br /> encountered, it is tikely that insufficient time was available for possible perched <br /> groundwater to seep into the bore hole and rise to its hydrostatic level. <br /> The Minnesota DNR reports the Ordinary High Water Level(OHW)of Lake Minnebonka <br /> to be around an elevation of 929�h feet. <br /> 3 <br />