1000 INDUSTRY ST 2018-01-02 MF Import

� January 28, 200� Project No. T-56>9 Prior to use, 'I'erra A.>sociates, Inc. should examine and test all materials imported to the site for use as structural I 611. Structmal fill should be placed in unifortn loose layers not ezceedin� 12 inches and campacted to a minimum of I 9� percent of the soil's maximum dry density, as determined by American Society for Testing and �faterials (ASTM) Test Designation D-698 (Standard Proctor;. The moisture content of the soil at the time ot"compaction should be within hvo percent of its optimum, as determined by this ASTM standard. In non-structural areas, the i dcerec oCcompaction can be reduced to 90 perccnt. I i4.3 Gxcat•ations All excavntions at the site associaicd with conFined spaces, such as utility tren.:hes, must Ue completed in accordance with bcal, state, or federal requirements. Based on the \\�ashington State Department of Labor and I Industries current occupational safety and health regulatinns, the existiag fill soils observed underlying the site would be classified as Type C soils. � Accordingly, side slopes on excavations in Type C soils should be sloped to an inclination of 1.5:1 (Horizontal:Vertical). Altemati��cly, utility trench sidewalls can be suppoRed by a propedy desioned and � installed slioring trench Uox. If these slope inclinations cannot be achieved due to sit� constraints, temporary � shoring �vould be required. This infonnation is provided solely for the benefit of the owner and other design consulta:us, and should not Ue � construed to imply that 'Ierra Associates, Inc. assumes responsibility for I�� site safety. It is underswod that job site safety is the solc responsibility of the project contractor. I 4.J Toimdations � Sprcad Fnntings In our opinion, thc buildi��gs may be suppartcd on com�entional sprcad Cooting foundations bcaring on �i undisturbed surfaces composed oC the existing fill soils, or ne�v swcmral till placed al �ve these competent � existing site soils. All footing subgrade should be prepared as rccommended in Section 4.2 of this report and be obscrved by a quali(ied geotechnical engineer to veriCy soi: stability prior to footing construction. It should bc I noted that the soils are sensitive to moisture variation and will be easily disturbed by nonnal co�struction activity, especially when moist or wet. If disturbed, the soil �vill not be suitable for Foundation suppon. If foundations , will be constructed during wet wcathcr, [o mitigate soil disturbance, protecting the subgrade��ith,� four-inch layer � of crushed Uallast rock or lenn concrete mis should be considered. Pcrimeter foundations exposed to the weathcr sl�ould bear at a minimum deptl� of 1.5 feet below final exterior grades for Gost protection. Interior foundations cv� be constructed at any convenient depth belo�v tl�e floor slab. Ne recommend designing founda:ions For a net allowable bearing capacity of 3,000 pounds per square foot (ps�. Por short-term loads, such as wind anct seismic, a one-third increase in this allo�vable capacity can be used. Nith � the anticipated loads and Il�is b�aring svess applicd, building settlements should be less than one-half inch total and one-quaner diCCercntial. i i Pagc No. � � �a`�