1004 BROADWAY EVCC STUDENT HOUSING - REPORTS & FINAL DOCUMENTS 2017-01-13

Geotecluiic�l Report - __� � iscd �' Proposed Apartments: 1002, 1006, a11d 1008 Broadway StY•eet, L;verett, Washington May 12, 2015 G.2 STRUCTLIRAL FILL AND COMPACTION Structural fill, should be free of organic and inorganic debris, be near the optimum moisture content and be capable of being compacted to the recommendations provided below. If the site soils cannot be compacted, then an imported structural fill may be needed. Fill for use during wet weather should consist of a well graded soil free of organic material with less than 5 percent ��ines (silt and clay sized particles passing the U.S. 200 sieve). Structural till should be moisture conditioned to within about 3 percent of optimum moisture content, placed in loose, horizontal lifts less than 8 inches in thickness, and compacted to at least 95 percent maximum density, determined using ASTM D-1557 (Modified Proctor). The procedure to achieve proper density of a compacted fill depends on the size and type of compacting equipment, the number of passes, thickness of the lifts being compacted, and certain soil properties. If the excavation to be backfilled is constricted and limits the use of heavy equipment, smaller equipment can be used, but the lift thickness will need to be reduced to achieve the required relative compaction. Generally, loosely compacted soils are a result of poor construction technic�ue or improper moisture content. Soils with high fines contents are particularly susceptible to becoming too wet and coarse-grained materials easily become too dry, for proper compaction. Silty or clayey soils with a moisture content too high for adequate compaction should be dried as necessary, or inoisture conditioned by mixing with drier materials, or other methods. C).3 WET WEATHER CONSTRUCTION General recommendations relative to earthwork performed in wet weather or in wet conditions are presented below. The following procedures are best management practices recommended for use in wet weather construction: • Earthwork should be performed in small areas to minimize subgrade exposure to wet weather. Excavation or the removal of unsuitable soil should be followed promptly by the placement and compaction of clean structural fill. The size and type of construction equipinent used inay have to be limited to p�•event soil disturbance. 1�-0-iS IOOR [3ru�td�ca}. Re��iscd I��1bC � 4 Pt1nG�,0, lI1C.