1921 W MUKILTEO BLVD 2018-01-02 MF Import

IPreliminary Geotechnical Engineering Evaluation I 1919 Mukilteo Boulevard October 20, 2005 NGA File No. 718805 Page 1 I passive resistance, respectively. To achieve this value of passive resistance, the foundations should be poured "neat" against the native medium dense soils or compacted fill should be used as backfill against the front of the footing. We recommend that the upper one -foot of soil be neglected when calculating the passive resistance. Structural Fill General: We do not anticipate large scale fill placement for this project; however, fill placed beneath foundations, pavement, or other settlement -sensitive structures should be placed as structural fill. Structural fill, by definition, is placed in accordance with prescribed methods and standards, and is monitored by an experienced geotechnical professional or soils technician. Field monitoring procedures would include the performance of a representative number of in -place density tests to document the attainment of the desired degree of relative compaction. The area to receive the fill should be suitably prepared as described in the Site Preparation and Grading subsection prior to beginning fill placement. Materials: Structural fill should consist of a good quality, granular soil, free of organics and other Ideleterious material and be well graded to a maximum size of about three inches. All-weather fill should contain no more than five -percent fines (soil finer than U.S. No. 200 sieve, based on that fraction passing Ithe U.S. 3/4-inch sieve). The use of on -site soils as structural fill should generally be feasible, but will be dependent on material moisture content at the time construction takes place. The on -site soils should be able to be used as structural fill provided these materials are near the optimum moisture content. We should be retained to evaluate proposed structural fill materials prior to construction. Fill Placement: Following subgrade preparation, placement of structural fill may proceed. All filling should be accomplished in uniform lifts up to eight inches thick. Each lift should be spread evenly and be thoroughly compacted prior to placement of subsequent lifts. All structural fill underlying building areas and pavement subgrade should be compacted to a minimum of 95 percent of its maximum dry density. Maximum dry density, in this report, refer to that density as determined by the ASTM D-1557 Compaction Test procedure. The moisture content of the soils to be compacted should be within about two percent of optimum so that a readily compactible condition exists. It may be necessary to over - excavate and remove wet soils in cases where drying to a compactible condition is not feasible. All compaction should be accomplished by equipment of a type and size sufficient to attain the desired degree of compaction. NELSON GEOTECHNICAL ASSOCIATES, INC.