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encountered at ±17 feet in a boring drilled in July 2013, when the ground water level is expected to be deeper. VdŬud`krnbnlokdsdcdwoknq`shnmrenqcheedqdnt projects at nearby locations along or adjacent to River Road. Explorations completed for a recent project east of River Road with similar soils and similar proximity to the Willamette River as the subject property encountered ground water infiltration as shallow as ±10 to 11 feet. The ground water was typically encountered near the top of the gravel stratum. Based on our observations and review of logs completed by others, we anticipate ground water fluctuates seasonally, closely corresponding to the rise and fall of the river level. Ground water has been documented as shallow as ±9 feet in a boring adjacent to the site. We anticipate perched water conditions will also develop within a few feet of the ground surface during periods of prolonged rainfall based on the presence of low permeable, fine-grained soils encountered at shallow depths across the site. FIELD AND LABORATORY TESTING Infiltration Testing Infiltration testing was completed at five locations in total. The tests are identified as P-1 through P-5. The approximate locations are shown on Figure 2A. P-1, P-2 and P-3 were completed in conjunction with the initial explorations between July 13 and 14, 2017. The locations were selected to give a range of infiltration measurements for the shallow soils across the property. P-1 was located next to TP- 2 and the test was performed at a depth of ±2.3 feet. P-2 was located next to TP- 5 and P-3 was located next to TP-6. Both P-2 and P-3 were performed at a depth of ±4 feet. P-4 and P-5 were completed between September 28 and 29, 2017, in conjunction with the supplemental explorations. The location and depths of P-4 and P-5 were coordinated with KPFF. P-4 was completed at the base of TP-9 at a depth of ±3.5 feet. P-5 was completed at the base of TP-10 at a depth of ±8 feet. The deeper test depth at P-5 was intended to help measure the infiltration rate of the deeper, sandier soils previously documented in TP-5 (see Figure 2A for test pit locations). However, the exploration at TP-10 did not encounter similar sandy soils to the maximum depth of the exploration. Therefore, the test was completed in soils described as low plasticity silt with trace sand. In general, each of the test locations encountered similar soils at the test depths, consisting of low to medium plasticity silt that ranges from clayey silt to silt with some clay or silt with trace sand. Additional descriptions are provided in the test pit logs (Appendix B). The tests were completed based on the guidelines detailed in Appendix G of the City of Eugene 2014 Stormwater Management Manual. Encased falling head tests were performed. At each location, we excavated to the test depth, then installed a 6-inch diameter casing ±6 inches into the soil. The pipe casing was filled with more than River Road Multi-Family Development April 30, 2018 Preliminary Geotechnical Investigation 4. Project 2171066 Eugene, Oregon Evergreen Housing Development Group, LLC