3003 COLBY AVE COURTYARD BY MARRIOTT 2021-03-09

Proposed Everett Hotel Property Environmental Site Characterization and ' Everett, Washington Remediation Recommendations 1.3 Subsurface Conditions A total , .loration borings were drilled for the project. These borings were drilled during t a a mg events. The initial drilling was conducted on January 19 and 20, 2009, and r included exploration borings EB-1 through EB-5. Additional drilling was conducted June 8 through 11, 2009 to further characterize the subsurface conditions and the extent of petroleum hydrocarbon impacted soil identified during the initial drilling event. As shown on Figure 2, eight o the borings (EB-1 through EB-6, EB-9, and EB-10)were drilled on the site, ano four (EB-7, EB-8, EB-11, and EB-12) were drilled in the adjacent Co1b, ,Avenue right-of-way. Of the borings drilled in the right-of-way, one (EB-7) was drilled in the sidewalk and the remainder were drilled in the angled shoulder parking on the east side of the Colby Avenue. IAll drilling was conducted using a Mobil B-61, truck-mounted, hollow-stem auger drilling rig equipped with 41/4-inch inside-diameter (ID) auger. During drilling, samples were generally obtained at 2.5- to 5.0-foot-depth intervals. The borings were continuously observed by iengineering geologists from our firm. The exploration logs presented in Appendix A are based on the field logs, drilling action, and inspection of the samples collected. Disturbed but representative samples were obtained using the Standard Penetration Test (SPT) procedure in accordance with American Society for Testing and Materials (ASTM):D 1586. This test and sampling method consists of driving a standard, 2-inch outside-diameter, split- barrel sampler a distance of 18 inches into the soil with a 140-pound hammer free-falling a distance of 30 inches. The number of blows for each 6-inch interval is recorded and the I number of blows required to drive the sampler the final 12 inches is known as the Standard Penetration Resistance ("N") or blow count. If a total of 50 is recorded within one 6-inch interval, the blow count is recorded as the number of blows for the corresponding inches of penetration. The resistance, or N-value, provides a measure of the relative density of granular soils or the relative consistency of cohesive soils; these values are plotted on the attached boring logs. The samples obtained from the split-barrel sampler were classified in the field and representative portions placed in watertight containers. The samples were then transported to our laboratory for further visual classification and laboratory testing, as necessary. 1.3.1 Stratigraphy Subsurface conditions at the site were inferred from the field explorations accomplished for this study, visual reconnaissance of the site, and review of applicable geologic literature. As shown on the field logs, the exploration borings generally encountered natural, granular, glacial sediments. Fill soils were also found at some borings locations. The following presents more detailed subsurface information organized from the shallowest (youngest) to the deepest(oldest) sediment types. t August 24, 2009 ASSOCIATED EARTH SCIENCES, INC. TJP/tb-KV090168A5-Projects1200901681KV1WP Page 2