3617 UPLAND AVE Geotech Report 2025-03-28

GeoTest Services, Inc. April 15, 2021 3617 Upland Avenue, Everett,WA Project No. 21-0375 General Geologic Conditions Geologic information for the project site was obtained from the Distribution and description of geologic units in the Mukilteo quadrangle, Washington (Minard, 1982). According to this publication, geology within the vicinity of the project site consists of Vashon Till (map unit Qvt) and Transitional Beds (map unit Qtb) of the Frasier Glaciation event, as well as the older Whidbey Formation (map unit Qw). The Transitional Beds typically consist of mostly clay, silt, and fine to very fine sand with some lenses of gravel and peat. The depositional environments associated with Transitional Beds are hypothesized to be that of glaciolacustrine and glaciofluvial deposits, mostly prior to glacial advance southward. Our on-site explorations indicate that the encountered subsurface soil conditions are generally in accordance with the mapped Transitional Beds. Groundwater At the time of our site visit on March 18, 2021, perched groundwater seepage was encountered within the lower portion of the subject property (TP-2) at an approximate depth of 3 feet BGS. GeoTest observed this seepage to be slight and located atop dense and native soils. Higher soil densities can decrease the saturated conductivity of soils depending on composition. The groundwater conditions reported on the exploration logs are for the specific locations and dates indicated, and therefore may not be indicative of other locations and/or times. Groundwater levels are variable and groundwater conditions will fluctuate depending on local subsurface conditions, precipitation, and changes in on-site and off-site use. GEOLOGICALLY HAZARDOUS AREAS Our geotechnical investigation included an assessment of potential geologic hazards that include landslide, erosion, flood, liquefaction, and seismic hazards. According to Chapter 19.37 of the Everett Municipal Code (EMC), Geologically Hazardous Areas include areas that are "susceptible to erosion, landslide, seismically induced soil failure, or other geological events." Based on this information and our observations of the subject property, it does not appear that erosion, flood, liquefaction, or seismic hazards are present on or in the immediate vicinity of the subject property. A steep slope approximately 10 to 15 feet in height bisects the subject property. The slope did not appear to be showing signs of springs, seeps, cracks, or evidence of instability. The existing residence on the property is set back approximately 15 feet from the top of slope, in which GeoTest did not observe apparent cracking within the building's exposed stem walls. 4