HomeMy WebLinkAbout601342015 Geotech Assessment (2007)t
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1451
February 15, 2007
Larry Laporte
921 Daily Street
Edmonds, WA 98020
Re: Storm water
;ATUM GROUP
Street, Bellingham, WA 98225
hone (360) 714-9409
and .other site development re of
Tax Parcel 601342015 ~~:r`~` ~
Jefferson County, Washington
Dear Mr. Laporte:
It is my understanding that you are p:
my geology evaluation of your grope
three building areas on the site and p
those areas including recommendatic
storm water management recommen~
recommendations for building area 1
management, septic drain field and
where you are planning to build: bui:
evaluation of the site.
Storm water
It is my understanding that at least 65°
underling the areas of the property pro
drained and have enough storage capa~
home sites and access roads as long as
access roads are left in a natural state
area 1 and area 2 should readily qualif
water manual.
Building Area 1
Storm water from the access road wits
a manner that will allow sheet flow of
Storm water from the home site in bui
simply allowed to drip off of the roof
discharged within the 15-foot setback
sfi~ ~1
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JE~EA~U~~UUNIr ~~i:r~
eeding with site development plans on your property. In
dated November 8, 2005 I concluded that there were
sided you with recommendations for site development of
for storm water management. I inadvertently left out
ions, septic drain field and vegetation management
or clarity I am providing you a description of storm water
station management recommendations for the two areas
ig area 1 and building area 2 as described in the geology
of the trees on the subject property will be retained. Soils
used for development at building areas 1 and 2 are well-
ty that they should readily infiltrate storm water from the
he native soils outside the immediate home sites and
~d are not compacted or removed. As such building in
for full dispersion of storm water per the Ecology storm
in building area 1 should be handled by grading the road in
'the road surface onto the forest floor adjoining the road.
ding area 1 should be directed to a dispersion trench or
into the ground surface. No storm water should be
=rom the steep slopes north and south of the building area.
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Building Area 2
r ~ .~ 6013 y zc~~,~
Storm water on the access road within
in a manner that will allow sheet flow ~
adjoining the road. Storm water from 1
dispersion trench as much away from t
site consist of well-drained sand and g~
infiltrate into the ground. No storm wa
steep shoreline bluff or with 15 feet of
Septic Drain Fields
Septic drain fields for the home sites sl
drain fields are located within the build
building area 1 should be setback at lei
should be setback at least 30 feet from
and at least 15 feet back from the steep
Vegetation management
At building area 1 no trees should be
slopes north or south of the building
limbed or topped to create view corri
removed from the setback or steep sl
building area 2 should be handled by grading the road
water off of the road surface onto the forest floor
home site in building area 2 should be directed to
steep shoreline slope as practical. Because soils on the
gel, water from the dispersion trench should readily
should be discharged within 30 feet of the top of the
steep ravine slope.
ild not cause any slope stability problems as long as the
1 and building 2 slope areas. The septic drain field in
15 feet from the steep ravine slopes. The drain field
top of the steep shoreline bluff slope in building area 2
vine slope.
~ved from within the 15-foot setback or from the steep
Trees within the setback or on the steep slope may be
Any debris from limbing or topping should be
At building area 2 no trees should be r moved from the steep shoreline slope. Within the 30-foot
setback from the top of the steep shore ine slope at least one tree per 30-foot center should be left
in place. Trees within the setback or o the steep slope may be limbed or topped to create view
corridors. Any debris from limbing or opping should be removed from the setback or steep
slope.
Stratum Group appreciates the
questions regarding our reconr
Sincerely yours,
S tum Group
Dan McShane, M.Sc., L.E.G.
Licensed Engineering Geologist
Stratum Group
city to be of service to you. Should you have any
please contact our office at (360) 714-9409.
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File: 6.6.OSIIB
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