REVIEWED STM RESUB 4-Geotech ReportRESUB
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A division of Haley & Aldrich
MEMORANDUM
DATE: January 25, 2022
To: Todd Stine
From: David Winter, Hart Crowser, a division of Haley & Aldrich
Re: Addendum to October 25, 2021 Geotechnical Letter Report
Stine Residence - 21701981h Avenue West
Edmonds, Washington
19601-00
Jan 27 2022
CITY OF EDMONDS
DEVELOPMENT SERVICES
-- DEPARTMENT
22609 4
ZS12�-
This memorandum summarizes concurrence by Hart Crowser, a division of Haley & Aldrich (Hart
Crowser), with the drainage plans prepared by KPFF for the referenced property. After discussions with
you and the civil engineers at KPFF, we agree that it is reasonable to install a collection pipe at the base
of the reconstructed south slope to collect groundwater from the apparent spring and from new drains
installed into the reconstructed slope. The water will then be tightlined to the collection pond. In our
opinion, runoff from the spring and from the south slope was already draining west towards the existing
collection area in the current unimproved configuration. The new system will manage and direct that
flow.
We also have discussed with the City reviewer and with you and KPFF the design and operation plan of
the stormwater infiltration system into the west yard. The system of infiltration trenches and overflow
sections should allow a maximum volume of water to infiltrate within the newly constructed yard.
Our October 25, 2021 revised geotechnical design letter is superseded by the discussions, agreements,
and modifications as shown on the submitted plans and summarized in this letter. We have been a part
of those discussions and agree with the conclusions and interpretations of our original
recommendations.
\\haleya Id rich. com\share\sea_projects\Notebooks\1960100_sti ne_Residen ce_Drai n_Field\Deliverables\Memos\2022_0125_HCHA_Geotech
Letter Rpt Addendum_F.docx
3131 Elliott Avenue. Suite 600
Seattle. Washington 98121
206 324.9530