Finalized Contract Agreement Packet

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June 13,2023 HWA Project No. 2022-188-21 Standard Penetration Test (SPT) sampling was performed at 2.5-foot intervals in the upper 10 feet each boring and at 5-foot interval below 10 feet using a2.}-inch outside diameter split- spoon sampler driven with a 14O-pound automatic hammer, except at intervals where Shelby Tube samplers were pushed instead. During the SPT, samples were obtained by driving the sampler 18 inches into the soil with the hammer free-falling 30 inches. The number of blows required for each 6 inches of penetration were recorded. The Standard Penetration Resistance ("N-value") of the soil is taken to be the number of blows required for the ftnal 12 inches of penetration. If a total of 50 blows or more were recorded within a single 6-inch interval, the test was terminated, and the N-value was recorded as 50 blows for the number of inches of penetration. The N-value provides an indication of the relative density of the granular soils and the relative consistency of the cohesive soils. In selected borings, where soft compressible soils were encountered, thin-walled steel tube (Shelby Tube) samples were obtained in general accordance with ASTM 2937. The tubes are bolted on to drill rods and pushed directly into the soil by hydraulic pressure. The explorations were monitored and logged by an HWA geologist. The approximate locations of the borings were determined in the field by handheld GPS and are shown on the Site and Exploration Plan, Figure 2. Soil samples obtained from the borings were classified in the field and representative portions were placed in plastic bags and taken to our Bothell, Washington laboratory for further examination and testing. In addition, pertinent information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater occuffence was recorded. The stratigraphic contacts shown on the boring logs represent the approximate boundaries between soil types; actual transitions may be more gradual. The soil and groundwater conditions depicted are only for the specific date and locations reported, and therefore, are not necessarily representative of other locations and times. A legend of the terms and symbols used on the exploration logs is presented in Appendix A, Figure A-1, followed by the boring logs on Figures A-2 through A-9. 2.2 Lanoru.roRYTEsrrNG Laboratory testing of samples retrieved from our exploratory borings included moisture content, organic content, Atterberg Limits, particle size analyses, California bearing ratio, and one- dimensional consolidation testing. Physical and mechanical testing was performed at HWA's laboratory in Bothell, Washington. All testing was accomplished in general accordance with ASTM standards, as appropriate. The results of the laboratory testing completed to date are summarized in Appendix B. 42022-188-21 KCTS - Final Geotechnical Report HWA GEoSCIENCES INC.