1710 W MARINE VIEW DR Geotech Report 2023-12-29

■ "Port of Everett Waterfront Place Central PGL Site 30% Design Drawings," prepared for Port of Everett, by PND Engineers, Inc., dated September 1, 2021. As shown in Figure 2, there is no existing geotechnical information (e.g., standard penetration tests [SPT], cone penetration tests [CPT], or test pits) available within the PGL building footprint; therefore, a geophysical survey was performed at the project site to correlate with the existing geotechnical information near the building footprint to evaluate the subsurface conditions within the building footprint. 2.1. Bulkhead Conditions The PGL site is located at the corner of 18th Street and the West Marine View Drive (State Route 529). The north boundary of the project site is approximately 80 feet south to the bulkhead at the South Marina, next to the Inn at Port Gardner; and the proposed retail building footprints are approximately 200 feet south of the bulkhead. An existing retail store building is on the west side of the project site. Based on our communication with the Port and PND, we understand that the bulkhead north of the project site is basically a rock dike built in the mid-1970s, with marine sediment fill behind the dike, and a concrete retaining wall, about 3 feet high, is sitting on top of the rock dike. Based on the review of available engineering drawings, nearby geotechnical information (e.g., boring logs), and survey drawings within the site vicinity, we assumed a constant existing ground surface across the project site at about Elevation +18.00 feet. The slope in front of the dike was assumed to slope down at an approximate 1.5H:1V (horizontal to vertical) slope from Elevation +16.00 feet to Elevation +1.00 feet, and an approximate 5.5H:1V slope from Elevation +1.0 feet to Elevation -12.00 feet. The elevation of -12.00 feet was the dredge elevation in front of the bulkhead from the nearby project. Note that the project vertical datum is Mean Lower Low Water (MLLW). 2.2. Subsurface Conditions Based on our review of the nearby subsurface information, the soils at the project site generally consist of hydraulic fill, recent deposits, and glacially consolidated soils. Hydraulic fill generally consists of soft sandy silt (ML) and loose to medium dense silty sand (SM) containing wood debris, organics, and shell fragments at some locations. Recent deposits were encountered below the hydraulic fill and generally consist of soft to medium stiff sandy silt and loose silty sand containing wood debris, organics, and shell fragments at some locations. Some medium dense sands (SP) were observed at B-1 and P-3 under the above soft to medium stiff sandy silty and loose silty sand layer, which is also part of the recent deposits. Glacially consolidated soils were encountered below the recent deposits and generally consist of dense to very dense sand, extended to the depths explored. Glacially consolidated soils are competent bearing soils. The locations of the test pits, SPT, and CPT borings that were reviewed and used in our analyses are shown in Figure 2. The corresponding test pits, SPT, and CPT logs are presented in Appendix A. GWENGINEERS� April 1. 2022 Page 2 Fib- No V i 6 030 00