5109 SEAHURST AVE 2025-12-12 - Laserfiche WebLink

COBALT GEOTECHNICAL INVESTIGATION G E o S C I E N C E S EVERETT, WASHINGTON November 16,2018 1.o Introduction In accordance with your authorization, Cobalt Geosciences, LLC (Cobalt) has completed a geotechnical investigation for the proposed single family residence located at 5109 Seahurst Avenue in Everett, Washington(Figure 1). The purpose of the geotechnical investigation was to identify subsurface conditions and to provide geotechnical recommendations for foundation design, stormwater management, earthwork, soil compaction,pavements,and suitability of the on-site soils for use as fill. The scope of work for the geotechnical evaluation consisted of a site investigation followed by engineering analyses to prepare this report. Recommendations presented herein pertain to various geotechnical aspects of the proposed development,including foundation support of the new buildings. 2.0 Project Description The project includes subdivision of the parcel into two building lots followed by construction of a new single-family residence in the eastern portion of the property. An accessory garage and driveway will likely be constructed within the new property. Anticipated building loads are expected to be light and site grading will include cuts and fills on the order of 4 feet or less. We should be provided with the final plans to verify that our recommendations have been incorporated into the design. 3.0 Site Description The site is located at 5109 Seahurst Avenue in Everett,Washington (Figure 1). The property consists of one rectangular shaped parcel(No.00416600000400)with a total area of about 0.3 acres. The western portion of the property is developed with a single-family residence with daylight basement level. There are local rockery walls along the west property line and a modular block wall along the north and part of the eastern property lines. These walls are up to 6 feet in height and support fill and/or native soils within the subject property. The site slopes downward to the east and west from the central portion. The slopes are generally less than 15 percent in magnitude with topographic relief of less than 5 feet. There are locally steeper slopes near the western property line. These slopes are faced with rockery walls locally and have magnitudes of up to 30 percent and relief of about 6 feet. The site is vegetated with grasses,bushes/shrubs, along with variable diameter evergreen and deciduous trees. The site is bordered to the north,south,and east by single-family residences,and to the west by Seahurst Avenue. 1 PO Box 82243 Kenmore,WA 98028 cobaltgcopernail.com 206-331-1097