REVIEWED Pittman-Taylor Foundation Repair Geotechnical Peer Review Letter_4.29.2024Ff
UT
DBE/MWBE
April 29, 2024
HWA Project No. 2024-002-21 Task Order 24-03
City of Edmonds
121 5th Ave. N
Edmonds, WA 98020
Attention: Ms. Denise Nelson, CPT, Senior Permit Coordinator
Subject: Geotechnical Peer Review
Pittman/Taylor Foundation Repair
Building Permit No. BLD2024-0473
Edmonds, Washington
Dear Ms. Nelson,
An applicant proposes to underpin an existing residence that has experienced distress related to
soil settlement. The residence is located at 16012 74th Place West in Edmonds, Washington
(site). The site is located in the North Edmonds Earth Subsidence and Landslide Hazard Area. At
the City of Edmonds' (City) request, HWA Geosciences Inc. (HWA) has completed a
geotechnical peer review of the applicant's permit submittal package and the results of HWA's
review are summarized in the following letter.
HWA has completed a geotechnical peer review of the submittal package in accordance with the
scope outlined in Task Order No. 24-03, issued under the Professional Services Agreement dated
December 22, 2023, and based on phone conversations with City permitting staff on April 29,
2024. HWA reviewed geotechnical portions of the following documents for conformance with
standard engineering practice in the Puget Sound region:
• Longitude One Twenty Engineering & Design. 2023. Calculation Package for Foundation
Stabilization. September 20.
• Longitude One Twenty Engineering & Design. 2023. Plan Set. September 20.
• Jeffrey Taylor and Jeffrey Pittman. 2023. Covenant of Notification and Indemnification/Hold
Harmless. December 6.
• Jeffrey Taylor and Jeffrey Pittman. 2023. Applicant/Owner Liability and Landslide
Acknowledgement. December 6.
• Cobalt Geosciences, LLC. 2023. Limited Geotechnical Evaluation. Foundation Mitigation,
16012 74t' PI W, Edmonds, Washington. September 19.
• Cobalt Geosciences, LLC. 2024. Geotechnical Hazard Statement of Risk. Foundation
Mitigation, 16012 74' PI W, Edmonds, Washington. January 29.
21312 301h Dr. 5E, 5TE.110, Bothell, WA 98021 1 425.774.0106 1 hwageo.com
April 29, 2024
HWA Project No. 2024-002-21 Task Order 24-03
Section 19.10.030.B of the Edmonds Community Development Code indicates that projects such
as retaining walls, decks, and sheds may be considered minor activities. In HWA's opinion, the
proposed foundation underpinning is of a similar scope and scale as these activities and as such,
may also be considered a minor activity.
HWA reviewed geotechnical aspects of the applicant's submittal package and concludes that the
package is in accordance with standard geotechnical engineering practice in the Puget Sound
region.
O ' O
This letter has been prepared to facilitate the City of Edmonds' evaluation of permit submittal
documents for the proposed foundation underpinning at 16012 74th Place West in Edmonds,
Washington. HWA reviewed geotechnical portions of the documents for conformance with
standard geotechnical engineering practices. Review of non-geotechnical documents was
completed for the sole purpose of verifying compliance with the recommendations in Cobalt
Geosciences, LLC's geotechnical engineering report. HWA's peer review does not diminish the
responsibility of the applicant's geotechnical consultant to serve as the project's geotechnical
engineer of record. Furthermore, the applicant's consultants are responsible for preparing a
design suitable for site conditions.
If you have questions or comments, or if we can be of further service, please contact Sean Gertz
at 425.476.5543 or at sgertz@hwageo.com.
Sincerely,
HWA GEOSCIENCES INC.
1
Sean M. Gertz, P.E.
Senior Geotechnical Engineer
References
City of Edmonds. Edmonds Community Development Code, Chapter 19.10 Building Permits —
Earth Subsidence and Landslide Hazard Area. Current through Ordinance 4269, passed
April 25, 2023.
IWA GeoSciences Inc.