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Report of Geotechnical Exploration and Review <br />Fox Street Improvements, Orono, Minnesota AMERICAN <br />July 29, 2016 ENGINEERING <br />Report No. 20-14448 TESTING, INC. <br /> <br /> <br /> <br />Page 11 of 12 <br />program consisting of patching cracks and repairing of locally distressed areas would be <br />implemented. The seal coating of the pavement surface after 3 to 5 years often helps prolong <br />pavement lift. <br /> <br />7.0 CONSTRUCTION CONSIDERATIONS <br />7.1 Potential Difficulties <br />7.1.1 Water in Excavations <br />The strength and stability of the soils for road subgrades and utility support encountered at this <br />site can be greatly impacted by ground water, perched ground water conditions, or periods of <br />heavy precipitation. Where water is present, strength and stability can be greatly reduced, <br />especially with the more fine grained soils. The contractor should choose the appropriate <br />compaction method for street subgrades. <br /> <br />To allow for observations of the excavation bottoms, to reduce the potential for soil disturbance, <br />and to facilitate backfilling operations, we recommend that all freestanding water within the <br />excavation be removed prior to proceeding with construction. Based on the soils encountered, <br />we anticipate the groundwater can be handled with conventional sump pumping. <br /> <br />7.1.2 Disturbance of Soils <br />The on-site soils can become disturbed under construction traffic, especially if the soils are wet. <br />If soils become disturbed, they should be subcut to the underlying undisturbed soils. The subcut <br />soils can then be dried and recompacted back into place, or they should be removed and replaced <br />with drier imported fill. <br /> <br />7.1.3 Cobbles and Boulders <br />The soils at this site can include cobbles and boulders. This may make excavating procedures <br />somewhat more difficult than normal if they are encountered. <br /> <br />7.2 Excavation Backsloping <br />If excavation faces are not retained, the excavations should maintain maximum allowable slopes <br />in accordance with OSHA Regulations (Standards 29 CFR), Part 1926, Subpart P, <br />“Excavations” (can be found on www.osha.gov). Even with the required OSHA sloping, water