3617 UPLAND AVE Geotech Report 2025-03-28

GeoTest Services, Inc. April 15, 2021 3617 Upland Avenue, Everett,WA Project No. 21-0375 material placed in accordance with subsequent recommendations for structural fill. During periods of wet weather, proof rolling could damage the exposed subgrade. Under these conditions, qualified geotechnical personnel should observe subgrade conditions to determine if proof rolling is feasible. Fill and Compaction Structural fill must be properly placed and compacted. In most cases, suitable, non-organic, predominantly granular soil may be used for fill material provided the material is properly moisture conditioned prior to placement and compaction, and the specified degree of compaction is obtained. Material containing topsoil, wood, trash, organic material, or construction debris is not suitable for reuse as structural fill and should be properly disposed off- site or placed in nonstructural areas. Soils containing more than approximately five percent fines are considered moisture sensitive and are difficult to compact to a firm and unyielding condition when over the optimum moisture content by more than approximately two percent. The optimum moisture content is that which allows the greatest dry density to be achieved at a given level of compactive effort. Reuse of On-Site Soil The non-organic, native,glacial soils are suitable for reuse as structural fill when placed at or near optimum moisture content, and if allowed for in the plans and specifications. Soils comprised of Transitional Beds contain high percentages of fines and should be considered moisture sensitive. Reuse of these soils may be considerably more difficult to use at or near perched groundwater elevations and during the wet weather season. If using on-site materials, the Contractor and Owner should be prepared to manage over optimum moisture content soils. The moisture content of the soils may be difficult to control during periods of wet weather. Imported Structural Fill GeoTest recommends that imported structural fill consist of clean, well-graded sandy gravel, gravelly sand, or other approved naturally occurring granular material (pit run) with at least 30 percent retained on the No. 4 sieve, or a well-graded crushed rock. Structural fill for dry weather construction may contain up to 10 percent fines (that portion passing the U.S. No. 200 sieve) based on the portion passing the U.S. No. 4 sieve. The use of an imported fill having more than 10 percent fines may be feasible, but the use of these soils should be reviewed by the design team prior to the start of construction. 7