4711 GLENHAVEN DR 2016-01-01 MF Import

`" - .ngineering geology practices in effect in this area at the time our report was prepared. No other warranty, expressed or implied is made. It must be understood that no recommendations or engineering design can yield a guazantee of stable siopes. Our observations, fmdings and opinions are a means to identify and reduce the inherent risks to the owner. 2.0 PROJECT AND SITE DESCRIPTION This report was completed with an understanding of the project based on a site plan and topographic sketch by the project architect, Mr. Robert Hazzard, dated September 14, 1997 and upon verbal information provided by Mr. Goldberg. Present plans call for consuvction of a three-story daylight basement house, located at the base of the site slopes. Pedestrian access to the house from adjacent Glenhaven Drive will be provided by a walkway bridge. Entrance ' onto the bridge will start from an off-screet parking area. Vehicle access to the residence - would be provided by a sloping driveway focated along the east perimeter of the property. i The residence will consist of conventional wood-frame consuucdon over a slab-on-grade floor. To achieve the proposed finish floor level at elevation 48, excavations on the order of 2 to 12 feet into the adjacent slope, and fills on the order of 3 to 5 feet will be required depending on the final siting of the house. The northeast perimeter area of the driveway may requ'ue a maximum fill depth of 13 feet to reach proposed grades. Additionally, the upper parking area and south end of tl�c bridge area may require s(ope excavations and fills of approxunately 5 to 7 feet in depth to cons[ruct concrete retaining walls proposed for this area. T6e building site is loczted on Lot 4 of the Glenhaven Plat in Everett, Washington. The site is . siivated along the east side of Glenhaven Drive, just south of an existing home at 470i Glenhaven Drive. The property is currendy undeveloped and comprises a pie-shaped area of 0.60 acres of which approximately the southwestem one-tfrird will be utilized for construction. The lot is bounded by Glenhaven Drive to the sou[h, a large residence to the northwest, and undeveloped land on the remaining sides. From Glenhaven Drive the site slopes steeply downward to an inclination of approximatel}� 1H:1V to 1.5H:1V (I-iorizontal:Vertical) with a relief of about 20 feet to the base of a broad swale. The swale in turn slopes gently downward to the nonheast. The eastern side of the swale is formed by a simifar steep slope which terminates into a ridge rop separating the site from the steep slopes above Pigeon Creek further to d�e east. The swale appears to be the head of a drainage which has been blocked off with fill placed for consuvction of Glenhaven Drive. No seepage or signs of surface water flow were noted within d�e swa]e at the time of our visit. However, runoff from Glenhaven Drive has been channeled onto the slope. The crests of the slopes along die southern margin of the site consisted of filf soils u�hich contained tension cracks near the slope crests indicating soil creep. A cat road located along the east side of the swale contained exposures of dense glacial till soil which are currendy standing at near vertical inclinations. The neighborine residence located ro the northwest appears to be founded within competent till soils. The swale is heavih� vccetated with brush and mature [rees. �