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glacial till deposits exhibit no stratified bedding and no sorted grain sizes of sand and gravel. <br /> Glacial till frequently has a clay matrix surrounding larger particles of silt, sand, and gravel with <br /> - occasional cobbles and boulders. Glacial till is deposited as either basal or ablation types. Basal <br /> glacial till is derived from glacial moraine debris embedded in the flowing ice near the bottom of the <br /> glacier (subglacial debris). This debris originates from eroded soil and rock beneath the glacier or <br /> debris that migrated downward through crevasses in the glacier (englacial debris). In contrast, <br /> ablation glacial till is formed from moraine debris that has accumulated (supraglacial debris) on the <br /> melted ice sheet surface. Often, the later deposited ablation till overlies and covers earlier <br /> deposited basal till. <br /> SOIL CHARACTER <br /> We have reviewed the Surficial Geology Map of Hennepin County and GEOLOGICAL <br /> CHARACTER section of this report Based on our review, the generalized soil profile in the vicinity <br /> of the project consists of a late Wisconsinan age Des Moines Glacial Ice Lobe glacial till deposit <br /> with a few beds and lenses of stratified sediment. <br /> Soil encountered in the borings include: <br /> - Gravelly Fill This was encountered in Boring 1 at the surface to a depth near 1 foot. It is dark <br /> brown silty gravel with sand. <br /> Topsoil and Buried Topsoil Topsoil was encountered in Boring 2 at the surface. to a depth <br /> near 1 foot. It is very dark brown sandy lean clay with organic matter. Buried topsoil was <br /> encountered in Boring 1 underlying gravelly fill. It extends below this fill to a depth near 3.5 feet. <br /> It is very dark brown to black, stiff, sandy lean clay that has minor amounts of organic matter. <br /> Horizon B Soil This was encountered in Borings 1 and 2 underlying topsoil and buried topsoil. <br /> It extends below topsoil and buried topsoil to depths near 3.5 and 6 feet It is light gray to light <br /> brown to dark gray, and it ranges from firm to stiff. Horizon B soil is sandy lean clay [ CL ] in <br /> Boring 1 and clay with sand [ CUCH ] in Boring 2: The CUCH clay is moderately plastic soil. <br /> Therefore, it is a potentially expansive or shrinkable soil, if its water content is altered up or <br /> down. <br /> Glacial Till This was encountered in Borings 1 and 2 to depths near 20 feet, and it consists of <br /> a stratum of ablation till overlying a stratum of basal till. The ablation till has relatively lighter <br /> coloring, including light brown and light gray colors. It is firm to stiff sandy lean clay, except in <br /> Boring 2 between depths near 7 and 12 feet where it is poor-graded fine sand that is loose to <br /> medium dense. The basal till has relatively darker coloring —dark gray typically. It is stiff sandy <br /> lean clay. <br /> Glacial Outwash This underlies basal glacial till in Boring 1., and it extends to the bottom of this <br /> boring. It is gray, medium dense, poor-graded fine sand. <br /> Allied Project 04049 4 July 27, 2004 <br />