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i . <br /> I supraglacial debris carried down to the bottom of the lacie <br /> g r through crevasses or from ground and <br /> bedrock under the flowing glacier. When wasting glacial ice eventually vanishes, supraglacial titl <br /> covering this ice is often deposited upon the earlier deposited subglacial till beneath the ice. <br /> Glacial till usually has a clay matrix, and larger particles of silt, sand, and gravel with occasional' <br /> cobbles and boulders are embedded within this matrix. <br /> Glacial lakes and former glacial lakes such as those along glacier margins and within kettle <br /> ; depressions on glacial till surfaces contain lacustrine deposits along their bottoms. These deposits <br /> � may range f�om inorganic granular and clayey soils to highly organic soils and peat. <br /> ', GROUND DESCRIPTION <br /> ' V1fe reviewed the Su�cial Geology Map of Hennepin Counfy, Minnesota and the GEOLOGY _ <br /> section of this report. The soil profile in the vicinity of the project site includes Des Moines Lobe <br /> and Grantsburg Sublobe glacial ice deposits, spec�cally the Twin Cities Formation therein. This <br /> formation contains glacial till that is unsorted sediment from clay to boulder sized. The till is <br /> oxidized yellowish to olive brown above the unoxidized gray till. The till has a few beds and lenses <br /> of strat�ed sediment. The Des-Moines deposit is underlain by Superior Lobe glacial ice deposits, <br /> which are more than 50 feet deep in this area. Soil encountered in the borings include: <br /> Natural Topsoil This was encountered from the ground surface to depths near 2 feet It is <br /> black lean clay with sand that contains organic matter. <br /> Horizon B Soil This underlies natural topsoil in Boring 2. It extends to a depth near 4 feet. It <br /> is light gray lean clay with sand that is stiff in its natural shear strength. <br /> Glacial Outwash This underlies natural topsoil in Boring 1. It extends to a depth near 4 feet. <br /> It is brownish gray poorly graded fine sand that is medium dense in its natural grain packing. <br /> Supraqlacial Till This underlies Horizon B soil and glacial outwash. It extends to the bottoms of <br /> the borings. It is light gray to brownish colored above depths near 13 feet and da�lc gray below <br /> depths near 13 feet. The till is sandy lean clay that is stiff to very stiff in its natural shear <br /> - strength. <br /> GROUND WATER <br /> Observations to detect water in the Borings are noted on Boring Logs in Appendix B. Observations <br /> were made during drilling and at ti�e end of drilling. Water was detected in Borings 1 and 2 near <br /> depths of 8 and 9 feet respectively. <br /> Notes in the Boring Logs indicate generally lighter soil color (brownish and light grayish) and brown <br /> mottling above depths near 13 feet This coloring is associated with an oxidized soil environment, <br /> which is typically underlain by tt�e anoxic soil environment. The anoxic soil environment is typically <br /> characterized by gray to dark gray soil with no mottling. The anoxic soil environment is associated <br /> Allied Project 05039 4 July 31, 2005 <br />