Geo Group NW Letter received 6-2-08.pdfffl X11 Group Northwest, Inc.
www
'-01111mvlay 30, 2008
Ms_ Jeannine L. Graf
City of Edmonds
Development Services Department
121-5 1h Avenue North
Edmonds, WA 98020
Subject: Geotechnical Peer.Review
Proposed Oates Residence Plan Revisions
7400 - 158" Street SW
Edmonds, Washington
Dear Ms. Graf:
Geotechnical Engineers, Geologists
& Environmental Scientists
RECEjIVED G-2384
2
BUILDING
At your request, we have reviewed the documents attached to the transmittal dated
May 15, 2008. Accordingly, the following issues are discussed in this review:
1. Cantilever retaining wall at driveway. The plans show a 4 to 6 foot tail concrete
retaining wall and Chris Covington has prepared the design of the wall. GED
Group Northwest, Inc_, has reviewed the geotechnical design parameters and
they are in accordance with Dennis Bruce's recommendations (May 17, 2005)
report for the project.
2. East yard shoring. The plans show a a two block high ecology block wail.
Dennis Bruce has a detail with the profile of the block and free draining backfill,
he backs it up with stability calculations. GEO Group Northwest, inc., is of the
opinion that this eco block wall is appropriate for the intended purpose.
3. Adding rockeries in the SW corner of the property. The plans show two tiers of 3
foot high rockeries at the SW corner of the site. GEO Group Northwest, inc.,
understands that the original topo survey did not have good ground contours at
this location due to the thick blackberry bushes, which required the building of
the subject rockeries. Rockeries are appropriate as erosion control for steep
cuts in stable soils. Geotechncial inspector need to verify that these conditions
exists at the subject location.
We trust that this review satisfies your peer review requirements.
Sincerely,
GEO Group Northwe , Inc,
Z�06��z
William Chang, P.E. 7
Principal Engineer
13240 NE 20th Street, Suite 10 • Bellevue, Washington 98005
Phone 425/649-8757 - Fax 425/649-8758