4729 VIEW DR 2023-12-08 - Laserfiche WebLink

• s• fib • GEO TECH 13256 Northeast 20th Street,Suite 16 Bellevue,Washington 98005 CONSULTANTS, INC. (425)747-5618 FAX(425)747-856I January 27, 2016 JN 16005 Robert and Lisa Flake do David Flake 4729 View Drive Everett, WA 98203 Subject: Geotechnical Engineering Study—Foundation Bearing and Slope Concerns Proposed Garage 4729 View Drive Everett, WA 98203 Dear Mr. and Mrs. Flake- The undersigned associate visited the subject site on December 21, 2015. The purpose of this visas to observe the existing site conditions,excavate some shallow test pits with your backhoe,and to develop opinions regarding the slope and the new garage that will be constructed on the eastern p9rtion of the subject site. The recommendations and conclusions presented in this report are professional Oinions based on the visual observations made during our site visit and on previous experience with similar projects. We excavated shallow test pits during our visit, but no deep subsurface explorations were conducted for our work. We were provided with a conceptual site plan. Based on this plan and discussions with you, we understand that a new, garage will be constructed on the eastern portion of the site with a setback of 20 feet from the steep eastern slope. The garage will be nearly level with the grade on the western end of the garage and will have a fill of about 5 to 6 feet on the eastern end of the garage. The eastern wall of the garage would be a 5 to 6 foot retaining wall to retain the slab fill. All grading is proposed on the western side of the garage to create the approach and parking area; no grading to the east of the garage is anticipated. The garage will be accessed by a driveway that descends the western sloping area along the alignment of the existing access path. If the scope of the project changes from what we have described above,we should be provided with revised plans in. order to determine if modifications to the recommendations and conclusions of this report are warranted. The eastern wall of the new garage will be located about 20 feet from the crest of a steep slope that extends down to the frontage road. This slope is moderate to steep and appears to be on the order of 20 feet tall. The slope was created by cutting in the road and the steep portion is a cut slope. The slope is well vegetated with trees, grass, and black berry vines. No evidence of large-scale slope instability was observed. The remainder of the lot slopes gently to moderately down to the east. Neighboring properties to the north and south are also residential and are graded in a similar manner to the subject. Our understanding of the subsurface conditions at the site is based on the observations made during our recent site visit and on experience gained from other projects in the site vicinity. During our visit, we observed the excavation of three test pits with aruftber tracked backhoe in the area of the garage (See Plate 2). The first test hole(eastern side of the garage)was located approximately 15 feet from the top of the slope and revealed 2 feet of loose fill overlying 6 inches of remnant topsoil over loose reddish-brown slightly silty sand that became loose to medium-dense at 3 feet.. 'Urtierlying the weathered sands at 4 feet, we encountered gray, dense, silty sand with gravel. This glacially comressed soil is commonly referred to as sandy glacial till. The second pit was just west of the garage, and this hole revealed 2 feet of loose fill and topsoil overlying loose to medium- dense slightly silty sand which in turn at 5 feet was underlain by dense, gray, silty sand. Our third hole was located at the western edge of�tae p oposed parking area and revealed just a foot of loose weathered silty sands overlying dense silty sands.All of the test pits were terminated in dense native soils(Detailed Logs Plate 3). GEOTECH CONSULTANTS,INC.