3400 RIVERFRONT BLVD Geotech Report 2022-10-25

• • • • APPENDIX A • FIELD EXPLORATIONS • • GENERAL • We drilled three borings at the site (B-1 through B-3)to investigate subsurface conditions. The borings were drilled to depths ranging from 51.5 to 56.5 feet BGS. The drilling was performed • by Holocene Drilling, Inc. of Puyallup, Washington. The drilling was observed by a member of our geotechnical staff. We obtained representative samples of the various soil encountered in • the explorations for visual classification and possible future laboratory testing. Classifications • and sampling depths are presented on the exploration logs included in this appendix. • The approximate locations of our explorations are shown on Figure 2. Exploration locations • were selected by GeoDesign based on the proposed development plans. The locations of the explorations were recorded using a GPS application on a smartphone. This information should • be considered accurate only to the degree implied by the methods used. • SOIL SAMPLING • Representative soil samples were obtained from the borings using the following methods: • • SPTs were performed in general conformance with ASTM D 1586. The sampler was driven • with a 140-pound automatic trip hammer free-falling 30 inches. The number of blows • required to drive the sampler 1 foot, or as otherwise indicated, into the soil is shown adjacent to the sample symbols on the exploration logs. Disturbed samples were obtained • from the split barrel sampler for subsequent classification and index testing. • • Shelby tube samples were collected in general accordance with ASTM D 1587. The 2.5-foot long, 3-inch-diameter, thin-walled, seamless steel tubes were pushed into the soil in one • continuous stroke. Each tube, together with the encased soil, was removed from the ground • and sealed. • The average efficiency of the automatic SPT hammer used by Holocene Drilling, Inc. was 77.0 percent. A copy of the calibration testing is presented at the end of this appendix. • • SOIL CLASSIFICATION • The soil samples were classified in accordance with the "Exploration Key" (Table A-1) and "Soil Classification System" (Table A-2), which are included in this appendix. The exploration logs • indicate the depths at which the soils or their characteristics change, although the change could • be gradual. A horizontal line between soil types indicates an observed (visual or digging action) • change. If the change occurred between sample locations and was not observed or obvious, the depth was interpreted and the change is indicated using a dashed line. Classifications and• sampling intervals are presented on the exploration logs included in this appendix. • • LABORATORY TESTING • We visually examined soil samples obtained from the explorations to confirm field classifications. • We also performed the following laboratory testing. • • • G EODESIGN= A-1 Polygon-128-01:09161 5