917 112TH ST SE Geotech Report 2022-10-25

Habitat for Humanity of Snoh8l'ish County ES-5168 April 26, 2017 Page 5 Temporary Erosion Control Temporary construction entrances and drive lanes consisting of at least six inches of quarry spalls can be considered in order to minimize off-site soil tracking and to provide a temporary road surface. Temporary slopes and stockpiles should be covered when not in use. Silt fencing should be installed along the margins of the property. Erosion control measures should conform to the Washington State Department of Ecology and City of Everett standards. Stripping Topsoil was encountered generally within the upper two to four inches of existing grades at the test pit locations. ESNW should be retained to observe site stripping activities at the time of construction so that the degree of required stripping may be assessed. Over-stripping should be avoided, as it is unnecessary and may result in increased project development costs. Topsoil and organic-rich soil is neither suitable for foundation support nor for use as structural fill. Topsoil and organic-rich soil may be used in non-structural areas, if desired. In-situ and Imported Soils The majority of the soils encountered during our subsurface exploration have a high sensitivity to moisture and were generally in a moist condition at the time of the exploration on March 29, 2017. The soils anticipated to be exposed at this site will degrade rapidly if exposed to moisture. In general, soils encountered during site excavations that are excessively over the optimum moisture content will require aeration or treatment prior to placement and compaction. Conversely, soils that are substantially below the optimum moisture content will require moisture conditioning through the addition of water prior to use as structural fill. An ESNW` representative should determine the suitability of in-situ soils for use as structural fill at the time of construction. Imported soil intended for use as structural fill should consist of a well-graded, granular soil with a moisture content that is at or slightly above the optimum level. During wet weather conditions, imported soil intended for use as structural fill should consist of a well-graded, granular soil with a fines content of 5 percent or less (where the fines content is defined as the percent passing the Number 200 sieve, based on the minus three-quarter-inch fraction). Structural Fill Structural fill is defined as compacted soil placed in foundation, slab-on-grade, and roadway areas. Fills placed to construct permanent slopes and throughout retaining wall and utility trench backfill areas are also considered structural fill. Soils placed in structural areas should be placed in loose lifts of 12 inches or less and compacted to a relative compaction of 95 percent, based on the laboratory maximum dry density as determined by the Modified Proctor Method (ASTM D-1557). For soil placed in utility trenches underlying structural areas, compaction requirements are dictated by the local city, county, or utility district, and in general are specified as 95 percent relative compaction. Earth Solutions NW,LLC