2410 RAILWAY AVE Geotech Report 2023-04-06

• II Penske Truck Leasing-Proposed Service Facility,2410 Railway Ave,Everett,WA Mar.8,2019/Rev.Feb. 25,2020 IGeotechnical Engineering Report P1493-T18 It should be realized that the explorations performed and utilized for this evaluation reveal subsurface conditions only at discrete locations across the project site and that actual conditions in other areas could vary. Furthermore, the nature and extent of any such variations would not become evident until additional explorations are performed or until construction activities have I begun. If significant variations are observed at that time,we may need to modify our conclusions and recommendations contained in this report to reflect the actual site conditions. I 2_1 Auger Boring Procedures Our exploratory borings were advanced through the soil with a hollow-stem auger,using a track- mounted drill rig,operated by an independent drilling firm working under subcontract to MGI. An Iengineering geologist from our firm continuously observed the borings, logged the subsurface conditions, and collected representative soil samples. All samples were stored in watertight I containers and later transported to a laboratory for further visual examination and testing. After the borings were completed, the boreholes were backfilled in accordance with state requirements. I Throughout the drilling operation, soil samples were obtained at 21/2 to 5-foot depth intervals by means of the Standard Penetration Test (SPT) per American Society for Testing and Materials (ASTM:D-1586),or using a large split-spoon sampler. This testing and sampling procedure consists I of driving a standard 2-inch-outside-diameter steel split-spoon sampler 18 inches into the soil with a 140-pound hammer free-falling 30 inches. The number of blows struck during the final 12 inches is recorded on the boring logs. If a total of 50 blows are struck within any 6-inch interval,the driving is stopped, and the blow count is recorded as 50 blows for the actual penetration distance. The resulting blow count values indicate the relative density of granular soils and the relative consistency of cohesive soils. The enclosed boring logs describe the vertical sequence of soils and materials encountered in the I borings, based primarily on our field classifications and supported by our subsequent laboratory examination and testing. Where a soil contact was observed to be gradational,our logs indicate the g g average contact depth. Where a soil type changed between sample intervals, we inferred the I contact depth. Our logs also graphically indicate the blow count,sample type,sample number,and approximate depth of each soil sample obtained from the borings, as well as any laboratory tests performed on these soil samples. If any groundwater was encountered in a borehole, the Iapproximate groundwater depth is depicted on the boring log. Groundwater depth estimates are typically based on the moisture content of soil samples, the wetted height on the drilling rods,and I the water level measured in the borehole after the auger has been extracted. The soils were classified visually in general accordance with the system described in Figure A-1,which includes a key to our exploration logs. Summary logs of the explorations are included as Figures A-2 through I A-15. I I I Migizi Group, Inc. Page 3 of 17 r.11,1.I ,dill,