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ESBGU In BH-1, the fill is underlain by medium stiff, medium to high plasticity clay from ±2.5 to 5.3 feet. Elsewhere on the site, the fill and topsoil are underlain by medium stiff to stiff, non-plastic to low plasticity silt. The silt extended to the maximum depths of TP-1 and TP-6 (±7 to 11 feet). The silt extended to depth of ±7 to 10 feet in the other testpits. The silt transitions to sandy silt with depthat some locations. Field vane measurements in this stratum ranged from ±0.5 to >1.0 tsf. A thin layer of soft, grey silt was encountered below the brown siltin TP-4 and TP-5. The fine-grained soil is typically underlain by sandy gravel with some silt at depths ranging from ±7.5 to 12 feet. In BH-1 and TP-8, loose silty sand was encountered between the silt and sandy gravel strata. The sandy gravel is typically medium dense to very dense at depths ranging from ±7.5 to 12 feet.TP-1, TP-4, and TP-6 did not encounter the sandy gravel to the maximum depth of the explorations (±7 to 11 feet). However, we anticipate the gravel may be present at those locations at greater depths. The gravel extended to the maximum depth of BH-1 (±25.8 feet). Based on our previous explorations and a review of well logs in the vicinity of the project site, we anticipate the sandy gravel extends to a depth of ±80 feet. Ground Water The use of mud-rotary drilling methods precluded the measurement of ground water levels in the boring. No ground water or seepage was encountered in the exploratory test pits which extended to depths of up to ±12 feet. The explorations were completed following an extended period of dry weather. We reviewed logs of nearby water wells available from the OWRD website to estimate seasonal groundwater conditions. The logs indicate static water levels ranging from ±13 to 15 feet. Based on the iron-staining of the soils, we anticipate ground water levels to rise to within ± 7 feet of the ground surface in the wet winter and spring months. Perched ground water conditions may also develop near the ground surface during periods of prolonged wet weather due to the flat terrain and presence of relatively low permeable fine-grained soil. LABORATORY TESTING The laboratory work included moisture contents, percent fines, and Atterberg limits tests to help classify the soils according to the Unified Soil Classification System (USCS) and estimate their overall engineering properties. The results are summarized in Table 1C (Appendix C). Themoisture contents are also shown on the boring logs.Non-tested samples were visually classified in accordance with ASTMD2488-09a and ASTMD2487-11. Santa Clara Transit Center January 15, 2019 Geotechnical Investigation 3 Project 2181060 Eugene, Oregon Rowell Brokaw