4702 W GLENHAVEN DR 2020-06-16 - Laserfiche WebLink

ftNizitgi _................... Materials Testing & Consulting, Inc. ak _ a� Geotechnical Engineering•Materials Testing•Special Inspection•Environmental Consulting ltfl M ats Testing&Coney$'' July 17, 2019 Reed Hansen FILE COPY Hansen Construction PO Box 2841 Everett WA, 98213 Subject: Limited Critical Area Investigation Residential Deck Addition—Oskar Property 4702 West Glenhaven Drive, Everett,Washington MTC Project No.: 19B182 Dear Mr. Hansen: At your request, Materials Testing & Consulting, Inc. (MTC) has completed a limited-scope geotechnical investigation and critical area assessment, including site and slope visual reconnaissance, focused subsurface testing of foundation locations, and review of available geologic literature at the above referenced property proposed for construction of a new residential deck addition to the existing residence. According to drawings provided by the contractor, the deck will be attached to the northwestern portion of the existing structure and extending toward the slope, supported on isolated pier foundations. An approximate 20 foot setback from the top of the critical slope to the closest outer edge of the cantilevered wood platform is proposed,with the closest footings planned to be marginally further from the slope. The project site is an approximately 1/3-acre residential lot occupied by a single-family residence located along the top of a vegetated north- to northwest-facing slope. The vicinity is a developed neighborhood within Everett, Washington with similar residences and setbacks to the slope as at the project site. The critical slope is approximately 30 vertical feet high sloping on average 30 degrees to the northwest. MTC understands a targeted geologic evaluation for critical area geohazard assessment is required per City of Everett code due to the presence of the steep natural slope on the site and the proposed setback reduction needed for the deck addition. The following report presents the findings and conclusions of our site exploration and assessment, addresses the feasibility of deck construction at the proposed location, and provides geotechnical recommendations for the deck foundation intended to reduce the inherent risks associated with development in a geologically hazardous area. MTC has performed this critical area site investigation in accordance with project discussions with the client, and in consideration of City of Everett requirements for site review and development within or adjacent to a geologically critical area. Corporate • 777 Chrysler Drive • Burlington, WA 98233 • Phone 360.755.1990 • Fax 360.755.1980 SW Region • 2118 Black Lake Blvd. S.W.• Olympia, WA 98512 • Phone 360.534.9777 • Fax 360.534.9779 NW Region • 805 Dupont, Suite 5 • Bellingham, WA 98225 • Phone 360.647.6061 • Fax 360.647.8111 Kitsap Region • 5451 N.W. Newberry Hill Road, Suite 101 • Silverdale, WA 98383 • Phone/Fax 360.698.6787 Visit our website: www.mtc-inc.n:t 1