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~ `_ i ITCO ALLIED ENGINEERING C�. AN ALLIANCE OF INSTANT TESTfNG COMPANY AND QLL[ED TEST D ILLING Jobsite and Laboratory Testing, Geofechnrcal Services, Commercial, Residenfial and Municipal 7'I25 West 12fith Street, Suite#500 - Savage, MN 55378 Telephone: (952)890-736fi Fax: (952) 890-5883 March 11, 2014 Atlashomes Phone: 763-425-3333 14450 - 117�'Avenue North Fax: 763-390-0039 Dayton, Minnesofa 55369 mark@atlashomesmn.com RE: 1565 Maple Place � Orono, Hennepin County, Minnesota As requested, a site visit was made on March 11, 2014 at 12:04 P.M, to evaluate and test soils for the construction of a full basement single-famify residence. The proposed build area is located at the middle of the 3 remaining lots within the tract. A subsurface geotechnical investigation#11036 conducted by A[fied Test Drilling Company indicates possible unsuitable soils within the development, to an average depth of 6 '/2 to 8 feet, with ground water elevations varying from 14 to 20 feet. At the time of the inspection, an area approximately 30 feet by 14 feet by 8 '/z feet deep had been excavated within the SW section of the proposed build area. Removed materials consisted of undocumented fill, containing {oamy soils, tree branches & root debris, wood, concrete, an isofated car tire, and a 10" zone of organically stained clay (Horizon "B" soil). The base of the excavation consisted of a wet, soft sandy clay, with a small isolated area of the Horizon "B" soil rerrzaining adjacent to the east wall of the excaWation. To assess the relative strength of the base soils, a 5/8�" inch diameter smooth probe was used at random to penetrate the excavation interior. With full body weight applied, the probes indicated medium/soft soils with probe penetration averaging 1 '/Z to 2 '/Z feet. Subgrade soil conditions were further evaluated by a 1 5/8'h inch diameter fluted hand auger probe put down excavation. The extracted cohesive soils were uniform in classification, and gained strength at depth. The load bearing capacity of the soils were evaluated by a dynamic cone penetrometer test conducted at the base of the excavation. The dynamic cone penetrometer (DCP), employs a eight kilogram (17.6 pound) hammer to drive a 20 millimeter diameter canica! pair�t into the soil, with the penetration recorded in millimeters per blow. From the DCP readings, a per blow, penetration average was recorded and a N-value derived. This N-value is an empirical relationship we hav� established to equate the dynamic cane data to the more familiar blows per foot (BPF) standard penetration sail boring test.