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May 4, 2018
c/o Bill Rehe
Edward Savidge
485 Griffith Point Road
Nordlund, Washington 983 5 8
Reference:Geotechnical Memorandum for Property Located at 485 Griffith Point Road, Nordlund,
Washington
To Whom It May Concern:
Envirotech Engineering, PLLC has completed a site evaluation of the referenced property and its existing
bulkhead, and prepared this geotechnical memorandum in support of the planned bulkhead replacement.
Our site visit was performed on April 22,2018 in order to evaluate the existing bulkhead and surface/
subsurface conditions.
The bulkhead is in very poor condition, and generally consists of I - to 4-man basalt that has a maximum
height of approximately 8 feet. Both neighboring properties have basalt rock bulkheads in good condition
with 4-man basalt construction. Significant upslope groundwater is evident on the property from the type
of vegetation within the backfill. Backfill soils were observed to be loose to medium dense poorly graded
sand and silty sand soils. The beach consisted of zero to 3 inches of sand and gravel sediments over
bedrock.
Currently, the bulkhead is failing as observed from the exposed cavities behind the wall allowing backfill
soil erosion to occur. In addition, bulkhead rock topples were observed as well as a lack of geotextile
behind the wall to mitigate erosion. Due to the existing failures of the wall, future failures could
accelerate and create a hazardous condition to the nearby existing home within I to 3 years.
It is our opinion that the rock bulkhead should be replaced as soon as possible with larger rock similar to
neighboring bulkhead. Reinforced concrete is not recommended for this application due to neighboring
bulkhead types and environmental concerns. Soft shore armoring is also not recommended due to the
bank steepness and excess height of the current bulkhead. In addition, soft armoring would be difficult to
safely tie into the neighboring bulkheads creating problems for their existing strucutres.
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JUN 2 0 2018
JTFTERSON COUNry
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Thank you for the opportunity to work on this project. If you have any questions or need any further
assistance, please contact Michael Staten at 3 60-27 5 -937 4.
Sincerely,
Envirotech
Michael Staten, P.E.
Project Director
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