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Preliminary Geotechnical Engineering Report GeoPacific Project No. 18-4986, 177 Day Island Road, Eugene, Oregon 11 1 11 1 FIELD EXPLORATION AND SUBSURFACE CONDITIONS Our site-specific explorations for this report were conducted on July 3, 2018. A total of 2 mud rotary soil borings, performed By Western States Soil Conservation, were drilled to depths of 16.5 and 51.5 feet using a track mounted rig. The approximate locations of our explorations are indicated on Figure 2. It should be noted that exploration locations were located in the field by pacing or taping distances from apparent property corners and other site features shown on the plans provided. As such, the locations of the explorations should be considered approximate. The boreholes were drilled using a track-mounted drill rig and solid stem auger methods. At each boring location, SPT (Standard Penetration Test) sampling was performed in general accordance with ASTM D1586 using a 2-inch outside diameter split-spoon sampler and a 140-pound hammer equipped with a hydraulic mechanism. During the test, a sample is obtained by driving the sampler 18 inches into the soil with the hammer free-falling 30 inches. The number of blows for each 6 inches of penetration is recorded. The Standard Penetration Resistance ("N-value") of the soil is calculated as the number of blows required for the final 12 inches of penetration. If 50 or more blows are recorded within a single 6-inch interval, the test is terminated, and the blow count is recorded as 50 blows for the number of inches driven. This resistance, or N-value, provides a measure of the relative density of granular soils and the relative consistency of cohesive soils. At the completion of the borings, the holes were backfilled with bentonite. A GeoPacific geologist continuously monitored the explorations and logged the test pits and soil borings. Soils observed in the explorations were classified in general accordance with the Unified Soil Classification System. During exploration geotechnical conditions such as soil consistency, moisture and groundwater conditions were noted. Logs of test pits and soil borings are attached to this report. The following report sections are based on the conditions observed during our investigation and summarize subsurface materials encountered at the site. Soils Topsoil Horizon: Directly underlying the ground surface in the vicinity of the soil borings was a topsoil horizon consisting of dark brown, highly organic SILT (OL-ML). The topsoil horizon was generally loose, contained fine roots throughout, and extended to depths of approximately 6 to 10 inches when excavated by shovel. Alluvium: Beneath the topsoil horizon was fine to coarse-grained alluvium derived from fluvial deposits. The soils generally consisted of medium stiff SILT (ML) to loose SAND (SM) to (SP) in the upper 5 feet overlying dense to very dense poorly graded GRAVEL (GP) that was composed of subangular to rounded fragments of basalt. Willamette Formation: At depths of 15 to 17 feet the alluvium dense gravel transitioned to light tan to blue-green, stiff to very stiff SILT (ML) to medium dense silty SAND (SM) belonging to the Willamette Formation, with occasional rounded gravel and some wood detritus below 35 feet. These soils extended beyond the maximum depth of exploration, 51.5 feet. 18-4986, 177 Day Island Road GRPT 3 GEOPACIFIC ENGINEERING, INC. Version 1, August 27, 2018