20432 - Seasonal Grading Letter - KeckGEOTECH
CONSULTANTS, INC_
Kevin Keck and Heather Hathaway
538 Battery Street, Apt. 508A
Seattle, Washington 98121
via email. kevkeck(cb-me.com
Subject: Seasonal Grading Considerations
Proposed Single -Family Residence
15722 — 72"d Avenue West
Edmonds, Washington
Dear Mr. Keck and Ms. Hathaway:
2401 10th Ave E
Seattle, Washington 98102
(425)747-5618
September 23, 2022
J N 20432
The Earth Subsidence Landslide Hazard provisions of the Edmonds Community Development
Code (ECDC) Chapter 19.10 limits land development to the drier season of the year between
October 1st and May 1st. All groundwork, including grading and drainage installation are generally
supposed completed by September 30th but it can continue into October and beyond if a stamped
letter by geotechnical engineer of record confirming that the site is stable and work may continue
past the September 30th. This letter is regarding extending work into October and beyond.
As part of this this letter, a detailed schedule of work that establishes a completion date. Below is a
detailed schedule provided to us by the project contractor:
- October 10-14: Pour Foundation & Strip
- October 17-21: Waterproofing Concrete Walls
- October 24-28: Footing drains, interior/exterior, drain rock, exterior storm catch basins. Maybe a
little backfill
- October 31- Nov 8 Exterior/Interior backfill, grading, driveway, backfill around portion of house.
- Nov - 10- Pour slab basement, weather permitting
Adding a 2-week contingency to this schedule, a completion date of November 24 appears prudent
based on the provided grading schedule.
Several erosion control measures have been implemented already for the site, including covered
stockpiles, plastic covered slopes, a gravel construction entrance, and silt fences on the downslope
sides of the site. These measures have been providing very adequate erosion control for the project
over the last several months. We believe that, provided these measures are well maintained, they
are suitable to provide adequate erosion control into November as noted in the schedule above.
GEOTECH CONSULTANTS, INC.
Keck
September 23, 2022
JN 20432
Page 2
If there are questions regarding this letter, or if we can be of further service, please contact us.
cc: Studio Zerbey - Kyle Zerbey
via email: Kyle(a)studiozerbey.com
12 •
Respectfully submitted,
GEOTECH CONSULTANTS, INC.
D. Robert Ward, P.E.
Principal
GEOTECH CONSULTANTS, INC.