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Achilles Manufacturing—Axthelm Construction JN 10076 October 4, 2016 Page 2/ r , , �' u it tZ + �}Y Lam - - ,� u t ..�s �� r ,i. i .- '1TP-2 .' . ? :1 ` -TP + ; � . S I t ,. Y a .•. �+t`t +� ' TP-1 0-2.0' Grayish brown silty sand Fill with occasional gravel,Moist,Loose to medium-dense[FILL] 2.0-2.5' Tan brown with ironstains,silty Sand with occasional gravel,fine-to medium-grained,very moist,medium-dense.[SM] -becomes gray,very dense,at 2.5 feet Bottom of hole at 2.5 feet.No groundwater.No Caving TP-2 0-3.0' Grayish brown silty sand Fill with occasional gravel,Moist,Loose to medium-dense[FILL] 3.0-4.5' Tan brown with ironstains and roots,silty Sand with occasional gravel,fine-to medium-grained,very moist,medium-dense.[SM] -becomes gray,very dense,at 4 feet Bottom of hole at 4.5 feet.No groundwater.No Caving CONCLUSIONS AND RECOMMENDATIONS GENERAL Our explorations at the site found dense to very dense, native silty sands (glacial till) underlying up to 2.5 to 4.5 feet of loose fill and weathered silty sand soils. Based on our explorations, the proposed structure can be supported by conventional foundations bearing on the dense native soils. The on-site native sand soils are silty, and are thus moisture-sensitive. When wet, these soils can become softened from equipment and foot traffic.Therefore, if footings are constructed during wet weather, or when the soils are wet, it will likely be necessary to protect bearing surfaces with a layer of imported, clean crushed rock to prevent disturbance of the footing subgrades. The non-organic, silty sand soils can be reused as structural fill, provided that they can be are placed in dry weather and are at, or near,the optimum moisture content. The silty sand soils should not be placed in direct contact with foundation walls. The upper, heavily weathered silty sand contained a significant amount of organics, and should not be used as structural fill. We recommend that Geotech Consultants, Inc. be afforded the opportunity to review the development plans, to amend our recommendations as necessary, and to verify that the recommendations presented in this report are adequately addressed in the design. Such a plan review would be additional work beyond the current scope of work for this study, and it may include revisions to our recommendations to accommodate site, development, and geotechnical constraints that become more evident during the review process. We recommend including this report, in its entirety, in the project contract documents. This report should also be provided to any future property owners so they will be aware of our findings and recommendations. SEISMIC CONSIDERATIONS In accordance with the (Seattle) International Building Code (SBC) (IBC), the site soil profile within 100 feet of the ground surface is best represented by Soil Profile Type C (Very Hard Soil or Soft Rock). The site soils in GEOTECH CONSULTANTS,INC.