22708 95TH PL W.PDFiiiiii iiiii . 1
9304
22708 95TH PL W
ADDRESS
TAX ACCOUNTIPARCEL
BUILDING PERMIT (NEW S
COVENANTS (RECORDED)
CRITICAL AREAS: DETERMINATION: E] Conditional Waiver F1 Study Required F] Waiver
DISCRETIONARY PER -MIT #'S:
DRAINAGE PLAN DATED:
PARKING AGREEMENTS DATED:
EASEMENT(S) R-ECOR-DED FOR:
PERMITS (OTH
PLANNING DATA CHECKLIST DA:
SCALED PLOT PLAN DATED:
SEWER LID FEE $: LID #:
SHORT PLAT FILE: LOT: BLOCK:
SIDE SEWER AS BUILT DATED:
SIDE SEWER PERMIT(S) #:—
GEOTECH REPORT DATED:
STREET USE / ENCROACHMENT PERMIT
WATER METER TAP CARD DATED:
OTHER:
LATEMP\DS'Ps\Fomis\Street File Checklist.doc
PLANNING DATA
SINGLE FAMILY RESIDENTIAL
11 STREET=FI'LE I
Name: Kv�e, Kr-,��"
Site Addrels: W
Date: 9 /A () h)-T
Plan Check #:
Project Description: 14e.,z C-eG-,dee\ce—,
Reduced Site Plan Provided: (0 NO)
I Zoning:
Map Page: koq
I Corner Lot: (YES /0
Flag Lot:(D/ NO)
Critical Areas Determination #: C.QN-Qcx--G- CCQO
Study Required -> re �Je,
(7/ly/bp� 6'rIX CC---A-l4Z nez t4ec( Mlg�b; 4 %/24/0-f ) o0no-i-C
waiver orcvos;�A , ep-� 4\,,e� e,�\�� t/0 4 'a-a.270 w,,d reoywg
SEPA Determination: \okQQer' 6e+-6ze,\
Exempt — Q�%vjk ekwc\2, S-�� :;LGG C-YA �.,d ycqcy-o�kI.
Needed (for over 500 cubic yards of grading)
El Fee 0 Checklist El APO List with notarized form
Required
9 4; e F-�'
E)
Side:
y.s
I Side:
(S) V, 25 " lti
77- 5
Actual Setbacks
side. /*
Side:
Side:
751+0
11-77, +a
11 Detached Structures: None %NnocorN oc\ 0-11�
Rockeries: ?re,,Pqd , e &4.
Fences/Trellises. V"
Bay Windows/Projecting Modulation: Upper -Plau- over kcL.,e,- -0104ar CC\
X Stairs/Deck: IF a� \ v e,
foM--ed ut\c-ovex-ec/ c,,, -a�&r,\ i A, .c, er J
Height
Datum Point:
EQ> M" ce'ver 'R�Xm
DatumElevation:
Maximum Height Allowed:
Actual Height:
Other
Parking Required:
Parking Provided: 3
Lot Area:
2, CXDO 41
Maximum Lot Coverage: 35% Proposed:
'Foa�pr,-A c,9 Vo-,se, C/e,-V� -C,.A 9or0^ Over Z3 'a, V9? oco
Lot Coverage Calculations: j6waz a-,�
ADU Created: (YES A�3 \J
Subdivision:
Legal Nonconforming Land Use Determination Issued: (YES
Comments
AA,\
7.
Plan Revie
Planning Data Form 04-11-06.doc
Associated Earth Sciences, Inc.
= EE N 91 -0
ezIe6ra&y 25 Vem ofSemex
July 14, 2006
Project No. KE060383A
Mr. Kyle Kragseth
RESUB
22706 95" Place West
Edmonds, Washington 98020
NOV - 2 2007
Subject: Steep Slope Evaluation
BUILDING DEPARTMENT
CITY OF EDMONDS
Kragseth Short Plat
22706 95' Place West
Edmonds, Washington
Dear Mr. Kragseth:
As requested, Associated Earth Sciences, Inc. (AESI) has performed a geotechnical review of
the above -referenced project to deterriiine if it complies with Edmonds Community
Development Code (ECDC) 23.80.060 for alterations of Geologically Hazardous Areas or
associated buffers. This letter is based on a site reconnaissance and the excavation of three
exploration pits on May 30, 2006, a review of applicable geologic maps and appropriate City
of Edmonds code, and conversations with you regarding potential construction plans.
Figure I ' Site and Exploration Plan, attached, shows the approximate locations of the
exploration pits, existing site features, site topography, and building setback lines. The Site
and Exploration Plan is based on a site plan generated by Pacific Geomatic Services, Inc., and
provided by you. Geologic logs of the exploration pits completed for this study are included as
attachments to this letter.
The proposed project involves subdividing the existing lot into two lots, a remodel of the
existing house on Lot 1, the addition of a garage to the existing house, and the construction of
a second house'on Lot 2. The construction of the * garage on Lot I will necessitate a temporary
cut, approximately 7 feet high, into or immediately adjacent to a 40-percent slope. The
construction of the house on Lot 2 will necessitate a temporary cut of 10 to 11 feet into or
immediately adjacent to a 40-percent slope. Figure I includes 2-foot topographic contours; the
map was provided to AESI with the areas exhibiting 40-percent slopes or greater identified
with a diagonal hatch pattern.
Geological Characteristics
According to the 1:24,000 scale COMPOSite Geologic Map of the Sno-King Area, Washington
(Bootb, et al., 2004), the site is mapped as being on the edge of the Vashon lodgement
t ']]/Vashon advance outwash contact. It should be noted that geologic contacts at this scale are
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often approximately placed and should be viewed accordingly. The site generally slopes down
from northwest to southeast, with a maximum elevation change of approximately 22 feet. The
steepest slopes (approximately 60 percent) occur along the north -central side of the property.
Based on the explorations conducted for this study, the geology of the slopes can be
characterized in the following units:
Weathered Vashon Lodgement Till
Immediately below the forest duff/topsoil layer, approximately 5 to 6 feet of medium dense,
dry to moist, light brown to brownish gray, fine to medium sand with silt, little gravel, and
trace roots was observed.
Vashon Lodgement Till
Below 5 to 6 feet in depth in our explorations, sediments included dense, moist, light brownish
gray to gray, partially consolidated, fine to medium sand with fine gravel and silt, and were
interpreted as Vashon lodgement till.
No seepage or sloughing was observed in the exploration pits. Our site reconnaissance
indicated relatively stable slopes, with no signs of slope instability observed, such as bowl -
shaped landforms, bowed coniferous tree trunks, seeps, or obvious headscarps. A review of
the City of Edmonds Environmentally Critical Areas Draft Inventory Maps (Figure 6.0-1,
Potential Geologically Hazardous Areas) did not indicate the presence of Erosion, Landslide,
Steep Slope, or Seismic Hazard Areas; however, an area to the west of the site is mapped as an
Erosion Hazard Area.
Findings
Based on our field reconnaissance and exploration pits, and review of the available geologic
information, the following site characteristics were identified:
& The site includes slopes of 40 percent or greater.
a The soils were found in a medium dense or dense condition.
No seeps or evidence of ground water was observed within 9 to 11.5 feet of ground
surface in our explorations.
0 No indications of slope instability were observed.
It is AESI's opinion that the proposed construction may be completed Using the following
recommendations:
The garage on Lot I and the house on Lot 2 should utilize a building setback of at least
7.5 feet and a buffer of at least 7.5 feet from the toe of the Steep Slope/Landslide
Hazard Area. the Steep Slope/Landslide Hazard Area is located along the north and
northwestern portions of the property, as indicated by the hatched contours, provided
by Pacific Geornatic Services, Inc. on Figure 1.
The proposed, temporary cuts should be constructed at a IHAV (Horizontal: Vertical)
slope angle in the dense, unweathered glacial till (encountered approximately 5 to 6 feet
below ground surface), and at a 1.5H-lV slope angle in the upper, weathered, medium
dense sediments.
0 We recommend extending all foundation elements to the underlying lodgement till.
It is our opinion that the potential for slope -related failures due to deep-seated landsliding and
shallow debris flows at the site should be low after construction if the general
recommendations in this letter are followed.
We appreciate the opportunity to be of service on this project. Should you have any questions
regarding this letter or other geotechnical aspects of the project, please call us at your earliest
convenience.
Sincerely,
ASSOCIATED EARTH SCIENCES, INC.
Kirkland, Washington
Stanley S. Thompson P.G., P.Hg.
Senior Project Geolo'�jst
Attachments: Exploration Pit Logs
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Reference: Pacific Geomatic Services, Inc. SCALE IN FE7
Associated Earth Sciences, Inc. SITE AND EXPLORATION PLAN FIGURE I
KRAGSETH SHORT PLAT DATE 6106
EDMONDS, WASHINGTON
PROJ. NO. KE060383A
LOG OF EXPLORATION PIT NO. EP-1
z
:E
This log is part of the report repared by Associated Earth Sciences, Inc. (AESI) for the named project and should be
read together with that repoxfor complete interpretation. This summary agplies only to the location of this trench at the
CL
time of excavation. Subsurface conditions may change at this location wit the passage of time. The data presented are
a simpification of actual conditions encountered.
DESCRIPTION
Weathered Vashon Lodgement Till
Medium dense, dry to moist, light brown to brownish light gray, fine to medium SAND with silt, little
fine to coarse gravel, trace roots.
2
3
4
5
6
Vashon Lodgement Till
Dense, moist, light brownish gray, partially consolidated, fine to medium SAND with fine gravel and
7
silt.
8
9
10
11
12 —
Bottom of exploration pit at depth 11.5 feet
No seeps or sloughing-
13 -
14
15
16
17
18
19
Kragseth Short Plat
Edmonds, WA
Associated Earth Sciences. Inc.
-)gged by. SST Project No. KE060383A
1bhJ
Aoproved by. M" 5/30/06
LOG OF EXPLORATION PIT NO. EP-2
�2
This log is part of the report prepared by Associated Earth Sciences, Inc. (AESI) for the named pF oject and should be
:S
read together with that report for complete interpretation. This summary gplies only to the location of this trench at the
time of excavation. Subsurface conditions may change at this location wit the passage of time. The data presented are
a simplfication of actual conditions encountered.
DESCRIPTION
Weathered Vashon Lodgement Till
Medium dense, slightly moist to moist, brown, fine to medium SAND with fine to coarse gravel, little
silt, trace roots.
2
3
4
5
Vashon Lodgement Till
Dense, moist, light brownish gray, fine to coarse SAND with fine to coarse gravel, little silt,
6
occasional cobble, partially consolidated.
7
8
9
10
11 —
Bottom of exploration pit at depth 10 feet
No seeps or sloughing.
12 —
13 —
14 —
15 —
16
17
18
19
20
Kragseth Short Plat
Edmonds, WA
Associated Earth Sciences, Inc.
Project No- KE060383A
Logged by SST
5130/06
LOG OF EXPLORATION PIT NO. EP-3
This log is part of the report prepared by Associated Earth Sciences, Inc. (AESI) for the named project and should be
Zi
read together with that report for complete interpretation. This summary applies only to the location of this trench at the
time. The data
(D
time of excavation. Subsurface conditions may change at this location wit the passage of presented are
0
a simpification of actual conditions encountered.
DESCRIPTION
Weathered Vashon Lodgement Till
Medium dense, dry to moist, light brown, silty fine to medium SAND, few fine to coarse gravel, trace
1
to few cobbles, occasional boulders.
2
3
4
5
Vashon Lodgement Till
Dense, moist, gray, fine to medium SAND, little sift, little fine to coarse gravel, consolidated.
6
7
8
9
Bottom of exploration pit at depth 9 feet
10
No seeps or sloughing.
11
12
13
14
15
16
17
18
19
IMT.7
or-M
Kragseth Short Plat
Edmonds, WA
Associated Earth Sciences, Inc.
-)gged by SS—i Project No- KE060383A
APproved by 5i30106
0 , TM A 6
(�� PL UJ
STRUT FILF
EARTH
CONSULTING 7a67 -
INCORPORATED
RECEIVED
APR 18 2007
BUILDING DEPARTMENT
CITY OF EDMONDS
0 Environmental Services 0 GeotechniGal Engineering Q Construction Materials Testing 0 Special Inspections
ApriI17,2007
Mr. Kyle Kragseth
22706 95th Place West
Edmonds, Washington
CRITICAL AREAS REVIEW
KRAGSETH SHORT PLAT
22706 95TH PLACE WEST
EDMONDS, WASHINGTON
Project No. E-12891
Reference:
APPROVED BY PLANNING
Associated Earth Sciences, Steep Slope Evaluation Kragseth Short Plat, July 21, 2006.
Dear Mr. Kragseth:
As requested, Earth Consulting Incorporated (ECI) is pleased to present this letter
providing a review of current construction concerning the steep slope/landslide hazard
area. In preparing this letter, we reviewed the above -referenced letter by Associated
Earth Sciences.
Introduction
We understand that the above -referenced property is a rectangular parcel with its length
in a general east —west direction. Along the north property boundary, a steep slope of
approximately 22 feet in height and greater than 40 percent slope parallels the lot line
descending onto the Kragseth property from the north. No failures or signs of slope
instability were found in the slope.
We understand that it is proposed remove the entire existing structure and that two new
residences will be constructed on Lot 1 and Lot 2
STREET FILE
1805 1361h Place Northeast #201 - Bellevue, WA 98005 * (425) 643-3780 * Fax (425) 746-0860
eci@eci-mti.com - www.eci-mti.Gom
GunCAL AREAS RGMEW
April 17, 2007
Conclusions
E-12891
It is our opinion that the proposed demolition will not adversely affect the stability of the
slope, alter stormwater discharge and sedimentation, or impact other critical areas,
provided that the work on site is limited to the demolition of the existing house. The
proposed demolition conforms to the Edmonds City Code:
23.80.070 Development standards — Specific hazards
2. Alterations. Alterations of an erosion or landslide hazard area and/or buffer may only
occur for activities for which a hazards analysis is submitted and certifies that:
a. The development will not increase surface water discharge or sedimentation to adjacent
properties beyond predevelopment conditions;
b. The development will not decrease slope stability on adjacent properties; and
c. Such alterations will not adversely impact other critical areas
No excavation or tree removal should be performed on the slope.
When the proposed demolition is completed, ECI should be provided site plans to
recommend appropriate buffers and potential slope modification.
Limitations
Our scope of work for this project was limited to a review of the above -referenced letter
and a site plan for the subdivision. Our work did not include exploration of actual
subsurface conditions. Our engineering analyses and conclusions are based on the
reviewed information.
Our services have been performed in a manner consistent with the level of care and skill
ordinarily exercised by members of the profession currently practicing under similar
conditions in the area. No warranty, expressed or implied, is made.
We trust this letter meets your needs. If you have any questions, please call.
11CORIPMATED
Robert A. Blomquist, LG
Project Geologist
FZAMMW/Skp
Kristina M. Weller, PE
Principal
EARTH CONSULTIING INCORPORATED
Page 2
EARTH
CONSULTING
INCORPORATED
U Environmental Services Ll Geotechnical Engineering LJ Construction Materials Testing Ll Special Inspections
September 18, 2007
Revised November 23, 2007
Mr. Kyle Kragseth
22706 95th Place West
Edmonds, Washington 98020
RESPONSE TO COMMENTS
KRAGSETH SFR
22706 AND 22708 95TH PLACE WEST
EDMONDS, WASHINGTON
Project No. E-12891
References:
Associated Earth Sciences, Steep Slope Evaluation Kragseth Short Plat, July 21, 2006.
Erich 0. Tiettze and Associates, Inc, Two Lot Short Plat 22706 95th Place West, Sheets
S-1 and C-1—C-5, September 9, 2007.
Nash, Jones, & Anderson, The Rutledge V1 Plan 258Z Sheets A-1—A-6 and G-1
September 18, 2007.
Dear Mr. Kragseth:
As requested, Earth Consulting Incorporated (ECI) is responding to the geotechnical
comments from the City of Edmonds dated September 10 and November 6, 2007. Lot 1 is
22706 95th Place West and Lot 2 is 22708 95th Place West. The comments for both lots
are similar so will be addressed with this one letter. ECI will be the geotechnical engineer
of record for the project and we agree with the previous recomm e*ndations provided by
the referenced report by Associated Earth Sciences (AESI). The City's comment appears
in bold; our response follows.
1//*//,V
6"TREET FILE"
1805 1�6 th Place Northeast #201 e Bellevue, WA 98005 a (425) 643-3780 - Fax (425) 746-0860
eci@eci-mti.com * www.eci-mti.com
keSPONSG TO COMMENTS E-12891
September 18, 2007, Revised November 23, 2007
Comment 6. Geotechnical Report: Since the subject property is located adjacent to
a steep slope, a report by a geotechnical engineer is required. Please have a
qualified geotechnical engineer review the proposed building plans and write a
report that meets the requirements of ECDC 23.40 and 23.80. Please note that the
geotechnical report must address all proposed improvements on the site, including
the proposed residence, deck, patio, fence, rockery, and any tree removal outside
the footprint of development.
The critical areas considerations were addressed in the referenced letter by AESI, and
ECI concurs with their assessment in relation to the currently proposed development. The
site conditions have not changed since these reports were prepared, and they remain
valid for the currently proposed development. The development addressed by the AESI
report included the proposed residence on Lot 2 and remodel of the residence on Lot 1. It
is now proposed to construct a new residence on Lot 1; however, the impacts to critical
areas have not increased from the description provided in the AESI report. The AESI
report included explorations and a plot plan. No setbacks from the landslide hazard area
are recommended provided the recommendations for construction are followed.
The following sections provide the additional recommendations for foundations, retaining
walls, structural fill, seismic design, site drainage,'rockery construction, tree removal, and
other improvements.
Foundations
Based on the results of our study, in our opinion, the proposed building may be supported
on a conventional spread and continuous footing foundation system bearing on
competent native soil, structural fill, or competent fill. If unsuitable material such as buried
topsoil, organic material, or debris is encountered in the foundation excavation, the
unsuitable material should be removed and replaced with structural fill.
Exterior foundation elements should be placed at a minimum depth of 18 inches below
final exterior grade for frost protection. Interior spread foundations can be placed at a
minimum depth of 12 inches below the top of slab, except in unheated areas where
interior foundation elements should be founded at a minimum depth of 18 inches.
Continuous and individual spread footings should have minimum widths of 16 and 18
inches, respectively.
With foundation support obtained as described, for design, an allowable soil bearing
capacity of 2500 pounds per square feet (psf) may be used for medium dense native soils
or structural fill. Loading of this magnitude would be provided with a theoretical factor -of -
safety in excess of 3.0 against shear failure. For short-term dynamic loading conditions, a
1/3 increase in the above allowable bearing capacity can be used.
With structural loading as expected and provided the above design criteria are followed,
total settlement of less than approximately 1 inch is anticipated, with differential
settlement of approximately 0.5 inch. Most of the anticipated settlement should occur
during construction as dead loads are applied.
EARTH CONSULTING INCORPORATED Page 2
AESPONSE TO COMMENTS E-12891
September 18, 2007, Revised November 23, 2007
Horizontal loads can be resisted by friction between the base of the foundation and the
supporting soil and by passive soil pressure acting on the face of the buried portion of the
foundation. For frictional capacity, a coefficient of 0.35 should be used. Resistance due to
passive earth pressure may be computed using an equivalent fluid pressure of 300
pounds per cubic foot (pcf) for footings backfilled with structural fill. These values are
allowable values; a factor -of -safety of 1.5 has been included. As movement of the
foundation element is required to mobilize full passive resistance, the passive resistance
should be neglected if such movement is not acceptable. Unless covered by pavements
or slabs, the passive resistance in the upper 1 foot of soil should be neglected.
ECI should be retained to observe the foundation subgrade prior to placement of
structural fill, forms, or rebar.
Retaining Walls
Retaining walls should be designed to resist the lateral loads imposed by the retained
soils and applicable surcharge loads. Walls that are designed to yield can be designed to
resist the lateral earth pressures imposed by an equivalent fluid with a unit weight of 35
pcf. If walls are to be restrained at the top from free movement, the equivalent fluid weight
should be increased to 50 pcf. These values are based on horizontal backfill conditions.
Surcharges due to backfill slopes, hydrostatic pressures, traffic, structural loads, or other
surcharge loads are assumed to not act on the wall. If such surcharges are to apply, they
should be added to the above design lateral pressure.
The passive pressure, allowable bearing capacity, and friction coefficient previously
provided in the "Foundations" section are applicable to the retaining wall design.
To reduce the potential for hydrostatic pressures to build up behind the walls, retaining
walls should be backfilled with a free -draining material extending at least 18 inches
behind the wall. The free -draining backfill should consist of' either pea gravel or washed
rock. A rigid, 4-inch-diameter, schedule 40, perforated PVC drain pipe should be placed
at the base of the wall and should be surrounded by a minimum of 1 cubic foot per lineal
foot with pea gravel or washed rock. The pipe should be placed with the perforations
down. The remainder of the backfill should consist of structural fill.
Slab -on -Grade Floors
Slab -on -grade floors may be supported on competent native soil or structural fill. Loose or
disturbed subgrade soil must either be compacted to the requirements of structural fill or
replaced with structural fill.
Slabs should be provided with a capillary break comprised of a minimum of 4 inches of
free -draining sand or gravel. In areas where slab moisture is undesirable, a vapor barrier,
such as a 6-mil plastic membrane, should be placed beneath the slab.
EARTH CONSULTING INCORPORATED Page 3
hESPONse To commeNTs
September 18, 2007, Revised November 23, 2007
Structural Fill
E-12891
Structural fill is defined as compacted fill placed under buildings, roadways, floor slabs,
pavements, or other load -bearing areas. Structural fill should be placed in horizontal lifts
not exceeding 12 inches in loose thickness and compacted to a minimum of 95 percent of
its laboratory maximum dry density determined in accordance with ASTM Test
Designation D1557 (Modified Proctor). The fill materials should be placed at or near their
optimum moisture content.
In our opinion, the native soils that will be encountered on site can be considered for use
as structural fill provided the soil is near its optimum moisture content at the time of
placement. Imported soil intended for use as structural fill should consist of a fairly well -
graded granular soil with a moisture content that is at or near its optimum moisture
content and has a maximum aggregate size of 4 inches. During wet weather conditions or
where groundwater seepage is encountered, structural fill should consist of a fairly well -
graded granular material having a maximum aggregate size of 4 inches and no more than
5 percent fines passing the U.S. No. 200 sieve.
Seismic Design Considerations
Earthquakes occur in the Puget Lowland with regularity; however, the majority of these
events are of such low magnitude they are not detected without instruments. Large
earthquakes do occur, as indicated by the 1949, 7.2 magnitude earthquake in the Olympia
area and the 1965, 6.5 magnitude earthquake in the Midway area and the 2001, 6.8
magnitude earthquake in the Nisqually area.
There are three potential geologic hazards associated with a strong motion seismic event
at this site: ground rupture, liquefaction, and ground motion response.
Ground Rupture
The strongest earthquakes in the Puget Lowland are widespread, subcrustal events,
ranging in depth from 30 to 55 miles. Surface faulting from these deep events has not been
documented to date. Therefore, it is our opinion, that the risk of ground rupture at this site
during a strong motion seismic event is negligible.
Liquefaction
Liquefaction is a phenomenon in which soils lose all shear strength for short periods of time
during an earthquake. Groundshaking of sufficient duration results in the loss of grain -to -
grain contact and rapid increase in pore water pressure, causing the soil to behave as a
fluid. To have a potential for liquefaction, a soil must be cohesionless with a grain -size
distribution of a specified range (generally sand and silt), it must be loose, it must be below
the groundwater table, and it must be subject to sufficient magnitude and duration of
groundshaking. The effects of liquefaction may be large total and/or differential settlement
for structures founded in the liquefying soils.
EARTH CONSULTING INCORPORATED Page 4
I
RESPONSE TO COMMENTS E-12891
September 18, 2007, Revised November 23, 2007
In our opinion, the liquefaction potential at this site is low to negligible. This conclusion is
based on the medium dense to dense soils encountered at the test pit locations and the
lack of a shallow groundwater table.
Ground Motion Response
The International Building Codee (IBC) regulations contain a static force procedure and a
dynamic force procedure for design -base shear calculations. Based on the encountered
soil conditions, it is our opinion Site Class C, "Very dense soil and soft rock," as defined in
Table 1615.1.1 of the IBC, should be used to characterize the site soils. In accordance with
Section 1615.1.2 of the IBC, Seismic Values, Sms =1.423 and Sm, = 0.639 should be used
for design.
Site Drainage
During construction, the site must be graded such that surface water is collected and
tightlined to an appropriate drainage facility. Water must not be allowed to stand in areas
where buildings, slabs, or pavements are to be constructed. Loose soil surfaces should
be sealed by compacting the surface to reduce the potential for moisture infiltration. Final
site grades must allow for drainage away from the building foundation. The ground should
be sloped at a gradient of 2 percent in paved areas and 3 percent in landscaped areas for
a distance of at least 10 feet from the buildings.
Footing drains may be installed around the perimeter of the building at or just below the
invert of the footing. Under no circumstances should roof downspout drain lines be
connected to the footing drain system. Roof downspouts must be separately tightlined to
discharge. Cleanouts should be installed at strategic locations to allow for periodic
maintenance of the footing drain and downspout tightline systems.
Permanent Slopes
Permanent cut and fill slopes should be inclined no steeper than 2H:1V
(Horizontal:Vertical). Cut slopes should be observed by ECI during excavation to verify
that conditions are as anticipated. Fill slope construction should also be observed under
the full time observation of an ECI representative to test structural fill soils.
Supplementary recommendations can be developed, if needed, to improve stability,
including flattening of slopes, placing erosion control fabrics, or installation of surface or
subsurface drains.
Permanently exposed slopes should be hydroseeded with an appropriate species of
vegetation to reduce erosion and improve stability for the surficial layer of soil immediately
after construction. In the summer months, it may be necessary to water the slopes to
maintain the hydroseed germination.
EARTH CONSULTING INCORPORATED Page 5
h6SPONSC- TO COMMENTS E-12891
September 18, 2007, Revised November 23, 2007
Rockery Construction and Modular Block Wall
Rockeries are proposed for the toe of the slope on Lot 1 with a height of less than 2 feet and
for the northeast portion and the western edge of Lot 2 with a height of less than 5 feet. The
rockeries are shown with drains tied into the proposed storm system. The block wall will
provide grade transition on the south side of Lot 2 with a maximum height of 2.5 feet. Based
on our review of the project, the construction of rockeries and block wall as proposed is
feasible from a geotechnical engineering standpoint.
The primary function of a rockery is to cover and protect an excavated or reinforced fill
surface that would essentially stand near vertical or vertical. Rockery construction is largely
a craft not entirely controllable by engineering methods. As such, it is imperative the
proposed rockeries be constructed in close conformance with the Associated Rockery
Contractors' (ARC) Standard Rockery Construction Guidelines and by an experienced
contractor with a proven capability in rockery construction. Rockeries should be embedded
12 inches into native soil. Fill soils or loose native soils should be removed and replaced
with structural fill or the base rock placed on the overexcavated surface. The rockery
subgrade and cut face should be observed by a representative of ECI.
Tree Removal
Several trees will be removed within the excavation for the proposed residences and
rockeries. Trees within the excavation should be cut and removed completely. Tree
removal within the steep slopes outside of the excavations necessary for the rockeries
and residences should be addressed on a case by case.basis. If less than 25 percent of
the roots of a tree will be removed as'part of the excavation, it is recommended to cut the
tree to within 6 inches of the ground surface and leave the remainder of the stump in
place. If more than 25 percent of the roots need to be removed, an ECI representative
should be contacted to discuss options of removal or leaving the stump in place. This
method of removal will maintain the existing stability of the slopes. Slope areas disturbed
should be at minimum seeded as recommended in the "Permanent Slopes" section of this
letter. No tree replacement is recommended.
Other Improvements
Other improvements will include patios, decks, and fences and are shown on the attached
site plans. ECI has provided input during the permitting and design phase . for the
locations of the fences in relation to the rockeries, and those recommendations have
been incorporated into the plans.
EARTH CONSULTING INCORPORATED Page 6
itESPONSE TO COMMENTS
September 18, 2007, Revised November 23, 2007
Plan Review
E-12891
ECI reviewed the referenced plans for the proposed buildings for the project and based
on that review, the plans incorporate the above recommendations for foundation design.
In addition, the attached site plans were reviewed and the plans are consistent with the
recommendation provided in this letter and the expected disturbances to critical areas
discussed in the AESI report. The prepared site plans comply with the development
standards of the Edmonds Community Development Code (ECDC) sections 23.80.060
and 23.80.070.
We trust this letter meets your needs. If you have any questions, please call.
Respectfully submitted,
EARTH CONSULTING INCORPORATED
r
331,R2:
4'/0 7
Kristina M. Weller, PE
Principal
KMW/skp
Attachment: Lot 1 and 2 Site Plans
EARTH CONSULTING INCORPORATED Page 7
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)0R010ERT,v AOORE-55- 22706 95TH PZACE HEST
,rAX ACCOUNT PARCEZ o#'- 00544300009100
VER7=411L DA
VERTICAL DATUM IS NAVD 88, BASED ON A PUBLISHED ELEVATION
FOR SNOHOMISH COUNTY POINT ID. SC31
ELEVATION: 367.972 LOT
I
BASIS OF
THE BASIS OF BEARING FOR THIS SURVEY IS NO'00'32"E BETWEEN
FOUND MONUMENTS ON THE CENTERLINE OF 95TH PL. W. AS SHOWN
ON THE PLAT OF PINECREST PAGE 55, VOLUME 13 OF PLATS, RECORDS
OF SNOHOMISH COUNTY, WASHINGTON.
SURIJEWRS NO
1. ALL EXISTING UNDERGROUND UTILITY LOCATIONS ARE BASED ON
OBSERVED EVIDENCE OF STRUCTURES. THE SURVEYOR MAKES NO
GUARANTEE THAT THE UNDERGROUND UTILITIES SHOWN COMPRISE ALL
SUCH UTILITIES IN THE AREA, EITHER IN-SERVICE OR ABANDONED. THE
SURVEYOR DOES NOT WARRANT THAT THE UNDERGROUND UTILITIES
SHOWN ARE IN THE EXACT LOCATION INDICATED ALTHOUGH HE DOES
CERTIFY THAT THEY ARE LOCATED AS ACCURATELY AS POSSIBLE FROM
THE INFORMATION PROVIDED.
2. ALL PROPOSED IMPROVEMENTS AND UTILITIES WERE PROVIDED BY
ERICH 0. TIETZE AND ASSOCIATES , INC. IN AN ELECTRONIC DRAWING
TITLED "SITE DEVELOPMENT PLAN" AND DATED 06/14/07.
LOT SIZE & COVER4GE BUILDING HEIGHT
TOTAL AREA: 9,212 SF A 353.92
(8,011 SF NET W/O ACCESS EASEMENT) B 354.10
C 355.91
2ND FLR FOOT PRINT/DECK/STAIRS/PORCH D 357.5
- 2,001 SF (25.0% NET)
1,421.46 (TOTAL)
IMP-ERMUS SURFA 355.37 (AVG)
IMPERVIOUS AREA - 4,151 SF (51.0% NET) 25.00 (MAX. BLDG
HEIGHT
ROOF - 2,018 SF 380.37 (MAX. ROOF
ELEV)
DRIVE - 1,921 SF 379.94 (ACT. ROOF
ELEV)
EXPOSED WALK/DECK/PATIOS - 174 SF
WALK - 38 SF
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EXPIRES: 10/02/
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VERDAr.4L DARM-
VERTICAL DATUM IS NAVD 88, BASED ON A PUBLISHED ELEVATION SVAAfY'0RS N07ES.- 5 WDE
FOR SNOHOMISH COUNTY POINT ID. SC31 1. ALL UNDERGROUND UTILITY LOCATIONS ARE BASED ON OBSERVED GRAPHIC SCALE
ELEVATION: 367.972 EVIDENCE OF'STRUCTURES. THE SURVEYOR MAKES NO GUARANTEE 0 10 20 40
THAT THE UNDERGROUND UTILITIES SHOWN COMPRISE ALL SUCH
BASIS OF BEA UTILITIES IN THE AREA, EITHER IN-SERVICE OR ABANDONED. THE
SURVEYOR DOES NOT WARRANT THAT THE UNDERGROUND UTILITIES
THE BASIS OF BEARING FOR THIS SURVEY IS NO'00'32"E BETWEEN SHOWN ARE IN THE EXACT LOCATION INDICATED ALTHOUGH HE DOES
FOUND MONUMENTS ON THE CENTERLINE OF 95TH PL. W. AS SHOWN CERTIFY THAT THEY ARE LOCATED AS ACCURATELY AS POSSIBLE FROM IN FEET NORTH
ON THE PLAT OF PINECREST PAGE 55, VOLUME 13 OF PLATS, RECORDS THE INFORMATION PROVIDED. I inch = 20 ft.
OF SNOHOMISH COUNTY, WASHINGTON.
LOT SIZE & COVERA 2. ALL PROPOSED IMPROVEMENTS AND UTILITIES WERE PROVIDED BY BUILDING HEIGHT D.
NOTE: A 359.75 V A s
TOTAL AREA: 8,000 SF SHORT PLAT FILE NO. ERICH 0. TIETZE AND ASSOCIATES, INC. IN AN ELECTRONIC DRAWING
2ND FLR FOOT PRINT/DECK/STAIRS/PORCH S-2006-0076 MUST TITLED "SITE DEVELOPMENT PLAN" AND DATED 06/14/07. B 357.83
- 2,199 SF (27.5%) BE RECORDED BEFORE PROOZRTr 0i0ZZ-RS- IrnZ- ,lrRAG5Z_7H C 367.73
M&MWOUS SVAFA BUILDING PERMITS CAN oR0PZ_RTr AOORf 5S.- 22706 .95TH PZACZ_ HEST D 370.1
IMPERVIOUS AREA BE ISSUED 7AXACC0lJNT,-ARCZ-Z 30.' 00,544JO0009700 1,455.46 (TOTAL)
- 4,122 SF (51.6%) TW = TOP OF WALL -0
363.87 (AVG) p
-ROOF - 2,018 SF BW = BOTTOM OF WALL 01-
-DRIVE - 1,890 SF 25.00 (MAX. BLDG HEIGHT S/0 AL UPMA'�
-EXP DECK/PORCH/STAIRS - 179 SF 388.87 (MAX. ROOF ELEV)
WALK - 35 SF LOT 2 S/ TE PLA N 386.18 (ACT. ROOF ELEV) EXPIRES: 10/02/
CPEARTH
CONSULTING
INCORPORATED
Q Environmental Services C1 Geotechnical Engineering 0 Construction Materials Testing Q Special Inspections
September 18, 2007
Mr. Kyle Kragseth *
22706 95th Place West
Edmonds, Washington 98020
RESPONSE TO COMMENTS
KRAGSETH-SFR
22706 95TH PLACE WEST
EDMONDS, WASHINGTON
Project No. E-12891
References:
SEP 2 12007
WILDING DEPARTMENT
CITY OF EDMONDS
Associated Earth Sciences, Steep Slope Evaluation Kragseth Short Plat, July 21, 2006.
Earth Consulting Incorporated, CriticalAreas Review, April 17, 2007.
Erich 0. Tiettze and Associates, Inc, Two Lot Short Plat 22706 95th Place West, Sheets
S-1 and C-1 —C-5, September 9, 2007.
Nash, Jones, & Anderson, The Rutledge VI Plan 2562, Sheets A-1—A-6 and G-1
September 18, 2007.
Dear Mr. Kragseth:
As requested, Earth Consulting Incorporated (ECI) is responding to the geotechnical
comments from the City of Edmonds dated September 10, 2007. The cities comment
appears below in bold, our response follows.
Comment 6. Geotechnical Report: Since the subject property is located adjacent to
a steep slope, a report by a geotechnical engineer is required. Please have a
qualified geotechnical engineer review the proposed building plans and write a
report that meets the requirements of ECDC 23.40 and 23.80. Please note that the
geotechnical report must address all proposed improvements on the site, including
the proposed residence, deck, patio, fence, rockery, and any tree removal outside
the footprint of development.
STREET FILE
1805 13611, Place Northeast #201 - Bellevue, WA 98005 - (425) 643-3780 * Fax (425) 746-0860
eci@eci-mti.com - www.eci-mti.com
RESPONSE TO COMMENTS
September 18. 2007
E-12891
The critical areas considerations were addressed by the referenced letters fro ' m
Associated Earth Sciences (AESI) and ECI. The AESI report included explorations and a
plot plan. The following sections provide the additional recommendations for foundations,
retaining walls, structural fill, and seismic design.
Foundations
Based on the results of our study, in our opinion, the proposed building may be supported on
a conventional spread and continuous footing foundation system bearing on competent
native soil, structural fill or competent fill. If unsuitable material such as buried topsoil,
organic material, or debris is encountered in the foundation excavation, the unsuitable
material should be removed and replaced with structural fill.
Exterior foundation elements should be placed at a minimum depth of 18 inches below final
exterior grade for frost protection. Interior spread foundations can be placed at a minimum
depth of 12 inches below the top of slab, except in unheated areas where interior foundation
elements should be founded at a minimum depth of 18 inches. Continuous and individual
spread footings should have minimum widths of 16 and 18 inches, respectively.
With foundation support obtained as described, for design, an allowable soil bearing capacity
of 2500 pounds per square feet may be used for medium dense native soils or structural fill.
Loading of this magnitude would be provided with a theoretical factor -of -safety in excess of
3.0 against shear failure. For short-term dynamic loading conditions, a 1/3 increase in the
above allowable bearing capacity can be used.
With structural loading as expected and provided the above design criteria are followed, total
settlement of less than approximately 1 inch is anticipated, with differential settlement of
approximately 0.5 inch. Most of the anticipated settlement should occur during construction
as dead loads are applied.
Horizontal loads can be resisted by friction between the base of the foundation and the
supporting soil and by passive soil pressure acting on the face of the buried portion of the
foundation. For frictional capacity, a coefficient of 0.35 should be used. Resistance due to
passive earth pressure may be computed using an equivalent fluid pressure of 300 pounds
per cubic foot (pcf) for footings backfilled with structural fill. These values are allowable
values; a facto r-of-safety of 1.5 has been included. As movement of the foundation element
is required to mobilize full passive resistance, the passive resistance should be neglected if
such movement is not acceptable. Unless covered by pavements or slabs, the passive
resistance in the upper I foot of soil should be neglected.
ECI should be retained to observe the foundation subgrade prior to placement of structural
fill, forms, or rebar.
EART14 CONSULTING INCORPORATED Page 2
RESPONSE TO COMMENTS
September 18, 2007
Retaining Walls
E-12891
Retaining walls should be designed to resist the lateral loads imposed by the retained soils
and applicable surcharge loads. Walls that are designed to yield can be designed to resist
the lateral earth pressures imposed by an equivalent fluid with a unit weight of 35 pcf. If walls
are to be restrained at the top from free movement, the equivalent fluid weight should be
increased to 50 pcf. These values are based on horizontal backfill conditions. Surcharges
due to backfill slopes, hydrostatic pressures, traffic, structural loads, or other surcharge loads
are assumed to not act on the wall. If such surcharges are to apply, they should be added to
the above design lateral pressure.
The passive pressure, allowable bearing capacity, and friction coefficient previously provided
in the "Foundations" section are applicable to the retaining wall design.
To reduce the potential for hydrostatic pressures to build up behind the walls, retaining walls
should be backfilled with a free -draining material extending at least 18 inches behind the
wall. The free -draining backfill should consist of either pea gravel or washed rock. A rigid, 4-
inch-diameter, schedule 40, perforated PVC drain pipe should be placed at the base of the
wall and should be surrounded by 8 minimum of 1 cubic foot per lineal foot with pea gravel or
washed rock. The pipe should be placed with the perforations down. The remainder of the
backfill should consist of structural fill.
Slab -on -Grade Floors
Slab -on -grade floors may be supported on competent native soil or structural fill. Loose or
disturbed subgrade soil must either be compacted to the requirements of structural fill or
replaced with structural fill.
Slabs should be provided with a capillary break comprised of a minimum of 4 inches of free -
draining sand or gravel. In areas where slab moisture is undesirable, a vapor barrier,.such as
a 6-mil plastic membrane, should be placed beneath the slab.
Structural Fill
Structural fill is defined as compacted fill placed under buildings, roadways, floor slabs,
pavements, or other load -bearing areas. Structural fill should be placed in horizontal lifts not
exceeding 12 inches in loose thickness and compacted to a minimum of 95 percent of its
laboratory maximum dry density determined in accordance with ASTM Test Designation.
D1557 (Modified Proctor). The fill materials should be placed at or near their optimum
moisture content.
In our opinion, the native soils that will be encountered on site can be considered for use as
structural fill provided the soil is near its optimum moisture co, ntent at the time of placement.
EARTH CONSULTING INCORPORATED Page 3
RESPONSE TO COMMENTS
September 18, 2007
E-12891
Imported soil intended for use as structural fill should consist of a fairly well -graded granular
soil with a moisture content that is at or near its optimum moisture content and has a
maximum aggregate size of 4 inches. During wet weather conditions or where groundwater
seepage is encountered, structural fill should consist of a faidy well -graded granular material
having a maximum aggregate size of 4 inches and no more than 5 percent fines passing the
U.S. No. 200 sieve.
Seismic Design Considerations
Earthquakes occur in the Puget Lowland with regularity; however, the majority of these
events are of such low magnitude they are not detected without instruments. Large
earthquakes do occur, as indicated by the 1949, 7.2 magnitude earthquake in the Olympia
area and the 1965, 6.5 magnitude earthquake in the Midway area and the 2001, 6.8
magnitude earthquake in the Nisqually area.
There are three potential geologic hazards associated with a strong motion seismic event at
this site: ground rupture, liquefaction, and ground motion response.
Ground Rupture
The strongest earthquakes in the Puget Lowland are widespread, subcrustal events,
ranging in depth from 30 to 55 miles. Surface faulting from these deep events has not been
documented to date. Therefore, it is our opinion, that the risk of ground rupture at this site
during a strong motion seismic event is negligible.
Liquefaction
Liquefaction is a phenomenon in which soils lose all shear strength for short periods of time
dudng an earthquake. Groundshaking of sufficient duration results in the loss of grain -to -
grain contact and rapid increase in pore water pressure, causing the soil to behave as a
fluid. To have a potential for liquefaction, a soil must be cohesionless with a grain -size
distdbution of a specified range (generally sand and silt), it must be loose, it must be below
the groundwater table, and it must be subject to sufficient magnitude and duration of
groundshaking. The effects of liquefaction may be large total and/or differential settlement
for structures founded in the liquefying soils.
In our opinion, the liquefaction potential at this site is low to negligible. This conclusion is
based on the medium dense to dense soils encountered at the test pit locations and the lack
of a shallow groundwater table.
GroundMotion Response
The International Building Code (IBC) regulations contain a static force procedure and a
dynamic force procedure for design -base shear calculations. Based on the encountered
soil conditions, it is our opinion Site Class C, 'Very dense soil and soft rock," as defined in
Table 1615.1.1 of the IBC, should be used to characterize the site soils. In accordance with
Section 1615.1.2 of the IBC, Seismic Values, Sms =1.423 and Sm, = 0.639 should be used
for design.
EARTH CONSULTING INCORPORATED Page 4
RESPONSE TO COMMENTS
September 18,2007
Site Drainage
=4211
During construction, the site must be graded such that surface water is collected and
tightlined to an appropriate drainage facility. Water must not be allowed to stand in areas
where buildings, slabs, or pavements are to be constructed. Loose soil surfaces should be
sealed by compacting the surface to reduce the potential for moisture infiltration. Final site
grades must allow for drainage away from the building foundation. The ground should be
sloped at a gradient of 2 percent in paved areas and 3 percent in landscaped areas for a
distance of at least 10 feet from the buildings.
Footing drains may be installed around the perimeter of the building at or just below the
invert of the footing, as shown on the 'Typical Footing Subdrain Detail," Plate 1. Under no
circumstances should roof downspout drain lines be connected to the footing drain system.
Roof downspouts must be separately tightlined to discharge. Cleanouts should be installed
at strategic locations to allow for periodic maintenance of the footing drain and downspout
tightline systems.
Plan Review
ECI reviewed the referenced plans for the project and.based on that review the plans
incorporate the above recommendations for foundation design.
We trust this letter meets your needs. If you have any questions, please call.
Respectfully submitted,
EARTH CONSULTING INCORPORATED
111917
Kristina M. Weller, PE
Principal
KMW/skp
Attachment: Plate I —Typical Footing Subdrain Detail
EARTH CONSULTING INCORPORATED Page 5
4 INCH MIN. DIAMETER
PERFORATED PIPE—
t
SLOPETO
DRAIN
2 INCH MIN.
2 INCH MIN,
4 INCH MAX, 12 INCH MIN.
Surface seal; native soil or other SCHEMATIC ONLY - NOT TO SCALE
low permeability material NOT A CONSTRUCTION DRAWING
Washed rock or pea gravel C=arth
Drain pipe; perforated or slotted Consulting
0 rigid Schedule 40 PVC: or SDR 35 Incorporatrid
pipe laid with perforations or slots
facing down; tight jointed; with a TYPICAL FOOTING SUBDRAIN DETAIL
positive gradient. Do not use KRAGSETH SFR
flexible corrugated plastic pipe. EDMONDS, WASHINGTON
Do not tie building downspout
drains into footing lines.
DRWN. DNM PROINO. 12891
CHKO.KMW DATE 9/18/07 PLATE 1
P
70
#P20
CA e No:
:Critical Areas Checklist F"
Site Information (soils/ topography/ hydrology/vegetation)
1.. .,...Site Address/1*4tign: :0270,4-
3>L 4.
2. Property TaxAccount Number: _490_�" 54
4 OoOCA -10-0
3. App.k.oxfinate. Site.Size, es,,Pr, s uare feet): 174.1 S'': -F-4.
4. 19 this* site currently deVeloped?
if yes; how isi site devA'*
loped?_ 5 J AJ. L F_ i4E.M.Cc
5. Describe the general site topogreiphy."'di kih�t applT',
M
A d, in; site,
Fl� va on ove�i,
over,,a ormntal
R s Jess- than 6f'
Piling, slope on �.siter generally
4600eo.Wfee
Hill
d re diAn 15% and less'than'30% (a vertic al - of'10-feet
y: -
_,qlpp,!�Sip OPO�10 _.site.6 rho
rise
-'W�'dis -.of 33,td 66-feet�"_
Unce
Steep:
Oresen 'Ott
�_,qf *r t of--'O-feet.�,over "aIorizontal'
distance of lez -than 33-fee9'"
Qthe' (pl�aseldekribe): v�
,of
areas t �pft
6.. Site contains yparrroun, stahi�� A'
d je wa Or ppr=-,,,,
'i " i ,� -,. , " " �, ." I " - - I
L
OL _�K
7. aregs. rason#s -Dqp
water
;AP-PSO&
ear?
What season(S),qfAhq y.
t cour6d
8. Site,is in of a wa'te
9. ;-,�Olq ;A,q teriflows s ffi , Yodk_?rO
5#f Pr�..Art'�arpa wa acros e,,,gr surf a��T. 'fil -are
ounds
,are�seasork-d?,.
1 Site. is- primarily-
04 forestLed'. ;-meadow.
u art
W �s
.rb,:, �. , !�� - "
11. Obviouswetl4nd-is -present on�site,
1.
2.
3.
4.
5.
C1,." u
tist4ff S-� C61Y
Plan C,h.e.ck.NW1nber,:if applicable?
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AIC001. 6WPC__ DETERMINATION
—STUDY REQUIRED
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City of Edmonds
Development Services Department
Planning Division
Phone: 42�371.0220
Fax: 425.771.0221
Date Received: '�t Zaq
City Receipt #:- Q qk
Critical Are asFile#: 1-0010-002-0
Critical Areas Checklist Fee: $135.00
Date Mailed to Applicant:
The CritiW*Areas,Checklist'c'o*�ntairW owthis form is to A property owner, or his/her authorized. repTesentative,
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be filled n -a�Dc 16pment gn
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CITY OF EDMONDS
CRITICAL AREAS RECONNAISSANCE REPORT
Sitet-ocation: 22706 95"' Place We�t Tax Acct. Number: 00544300009100
Determination: Study Required Determination #: CA-2006-0020
Applicant: Kyle A. Kragseth Owner: Kyle A. Kragseth
CRITICAL AREAS RECONNAISSANCE REPORT: STUDY REQUIRED (CA-2006-0020)
During review and inspection of the subject site, it was found that the site may contain or be
adjacent to critical areas, including Erosion Hazard Areas and a Landslide Hazard Area
pursuant to Chapter 23.40 of the Edmonds Community Development Code (ECDC).
GENERAL CRITICAL AREAS REPORT REQUIREMENTS
Critical Areas Reports identify, classify and delineate any areas on or adjacent to the subject
property that may qualify as critical areas. They also assess these areas and identify any
potential impacts resulting from your specific development proposal. If a specific development
proposal results in an alteration to a critical area the critical areas report will also contain a
mitigation plan. You have the option of completing the portion of the study that classifies and
delineates the critical areas and waiting until you have a specific development proposal to
complete the study. You may also choose submit the entire study with your specific
development application.
Please review the minimum report requirements for all types of Critical Areas which are
listed in ECDC 23.40.090.D. There are additional report requirements for different types of
critical areas (see below).
Note that it is important for the report to be prepared by a qualified professional as defined
in the ordinance. There are options on how to complete a critical areas study and an
approved list of consultants that you may choose from. You may contact the Planning
Division for more information.
General Mitigation Requirements for all Critical Areas are discussed in ECDC 23.40.110
through 23.40.140.
STUDY REQUIREMENT — EROSION HAZARD AREA
It appears that this property contains or is adjacent to an Erosion Hazard Area.
Erosion Hazard areas include Alderwood and Everett series soils on slopes of 15 percent or
greater. among others.
0 Landslide Hazard Areas are further defined in ECDC 23.80.020.A.
In addition to the general requirements for Critical Areas reports referenced above, specific
Critical Area report requirements for Erosion Hazard Areas (which are one of the
Geologically Hazardous Areas) are provided in ECDC 23.80.050.
Note that Stable Erosion Hazard Areas may have limited report requirements at the
director's discretion. At a minimum an erosion and sediment control plan prepared in
compliance with the requirements in ECDC Chapter 18.30 shall be required.
DEVELOPMENT PROPOSALS ASSOCIATED WITH EROSION HAZARD AREAS
Development is restricted within an Erosion Hazard Area.
Projects that will intrude into these areas will require a report by a licensed Geotechnical
Engineer or other qualified professional.
Development standards are given in ECDC 23.80.060 and 23.80.070.
STUDY REQUIREMENT — LANDSLIDE HAZARD AREA
It appears that this property contains or is adjacent to a Landslide Hazard Area. Please review
attached map — it appears that a slope of approximately 60% is on/adjacent to the property.
A Landslide Hazard Area is any area with a slope of forty percent (40%) or steeper and with
a vertical relief of ten (10) or more feet (except areas composed of consolidated bedrock).
* Landslide Hazard Areas are further defined and illustrated in ECDC 23.80.020.B.
In additionto the general requirements for Critical Areas reports referenced above, specific
Critical Area report requirements for Landslide Hazard Areas are provided in ECDC
23.80.050.
DEVELOPMENT PROPOSALS ASSOCIATED WITH LANDSLIDE HAZARD AREAS
Development is restricted within a Landslide Hazard Area and its buffer.
Projects that will intrude into these areas will require a report by a licensed Geotechnical
Engineer.
0 The criteria that are applied depend on the amount that the buffer is reduced.
The buffer can be reduced to a minimum often (10) feet (with an additional 15' building
setback per ECDC 23.40.280) if a report is prepared that meets the standards listed in
ECDC 23.80.050). The alteration must also meet the requirements listed ECDC 23.80.060.
In addition, proposals to reduce the buffer to less than ten (10) feet must comply with the
design standards listed in ECDC 23.80.070.A.3.
ALLOWED ACTIVITIES
Certain activities are allowed in or near critical area buffers as specified in ECDC 23.40.20. If
you have any questions about whether your proposed development qualifies as an allowed
activity, please contact a Planner for more information.
EXEMPT DEVELOPMENT PROPOSALS
Certain development proposals may be exempt from Critical Areas Requirements (ECDC
23.40.230). If you think that a specific development proposal may be exempt, contact a
Planner for more information.
Gina Coccia, Planner (49A429e V
Name, Title V Signature
Date
Ke =8%
NOTE: Cited sections of the Edmonds Community Development Code (ECDC) can be found on
the City of Edmonds website at www.ci.edmonds.wa.us.
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