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� � ITCO ALLIED ENGINEERING CO. AN ALLIANCE OF INSTANT TESTING COMPANY AND ALLIED TEST DRILLING Jobsite and Laboratory Testing, Geotechnica/ Services, Commercial, Residentia/and Municipal 7125 West 126th Street, Suite #500 - Savage, MN 55378 Telephone: (952)890-7366 Fax: (952)890-5883 May 8, 2013 Dean Johnson Homes Phone: 763-242-7301 4700 County Road #19 Medina, Minnesota 55357 RE: 1579 Maple Place Orono, Hennepin County, Minnesota As requested, a site visit was made on May 6, 2013 at 2:28 P.M. to evaluate and test soils for the construction of a full basement single-family residence. The proposed build area is located in a 3-lot tract. A subsurface geotechnical investigation #11036 conducted by Ailied Test Driliing Company indicates possible unsuitable soils within the site, with a site inspection conducted 6/29/12 within the adjacent lot, confirmed the requirement for soil corrections within this section of the site. At the time of the inspection, except for the garage area, the house foundation had been excavated to approx. footing elevation. The contractor had completed an exploratory test excavation within the northeast corner of the foundation excavation. At approximately 15 by 9 feet and 3 to 4 feet in depth, the excavation indicated fully saturated soils and buried undocumented fill, consisting of old tree debris and some concrete. Perched water rapidly filled the excavation to a depth of approximately 2 feet. A 1 5/8`h inch diameter fluted hand auger probe put down approximately 3 feet through the water, and into the subgrade soils, indicated a dark horizon "B" zone, underlain by a competent fine granular material at a depth of approximately 5 to 6 feet, capable of supporting full body weight applied to the probe. Observations indicate similar soil conditions and fill depths as those encountered within the neighboring lot tested June 29, 2012. Because of groundwater infiltration, soil load bearing tests were not conducted, however we would anticipate values approaching 2000 PSF as documented within the referenced adjacent lot. Based upon the observed soil conditions, the house pad should be excavated to remove all undocumented fill and associated debris. We would recommend some level of de-watering as the unsuitable materials are removed to the zone of dark granular horizon "B" soils, anticipated at a depth of 5 to 6 feet. Adjustments to proposed build elevation will be accompfished by a dropped footing design, and/or the placement of a coarse granular fill to above groundwater elevation. If the upper zone of fill consists of pit run material, we recommend the installation of a geotextile fabric as a separating or stabilization layer to minimize particle migration. RECEIVED I�iAY 1 0 2013 CITY OF ORONO