ENG2022-0536 CANODCity of Edmonds
Critical Area Notice of Decision
Applicant:
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Property Owner:
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Critical Area File #:
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Permit Number:
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Site Location:
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Parcel Number:
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Project Description:prct
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❑ Conditional Waiver. No critical area report is required for the project described above.
1. There will be no alteration of a Critical Area or its required buffer.
2. The proposal is an allowed activity pursuant to ECDC 23.40.220, 23.50.020, and/or
23.80.040.
3. The proposal is exempt pursuant to ECDC 23.40.230.
❑ Erosion Hazard. Project is within erosion hazard area. Applicant must prepare an erosion and
sediment control plan in compliance with ECDC 18.30,
Critical Area Report Required. The proposed project is within a critical area and/or a critical area
buffer and a critical area report is required. A critical area report has been submitted and evaluated
for co pliance with the following criteria pursuant to ECDC 23.40.160:
1. The proposal minimizes the impact on critical areas in accordance with ECDC 23.40.120,
Mitigation sequencing;
2. The proposal does not pose an unreasonable threat to the public health, safety, or welfare
on or off the development proposal site;
3. The proposal is consistent with the general purposes of this title and the public interest;
4. Any alterations permitted to the critical area are mitigated in accordance with ECDC
23.40.110, Mitigation requirements.
5. The proposal protects the critical area functions and values consistent with the best
available science and results in no net loss of critical functions and values; and
6. The proposal is consistent with other applicable regulations and standards.
❑ Unfavorable Critical Area Decision. The proposed project is not exempt or does not adequately
mitigate its impacts on critical areas and/or does not comply with the criteria in ECDC 23.40.160 and
the provisions of the City of Edmonds critical area regulations. See attached findings of
noncompliance.
pf-If Critical Area Decision. The proposed project as described above and as shown on the
attached site plan meets or is exempt from the criteria in ECDC 23.40.160, Review Criteria, and
complies with the applicable provisions of the City of Edmonds critical area regulations. Any
subsequent changes to the proposal shall void this decision pending re -review of the proposal.
❑ Conditions. Critical Area specific condition(s) have been applied to the permit number referenced
above. See referenced permit number for specific condition(s).
Notice on Title. Critical area notice on title recorded under AFN � 2 %o (t� Z S-�
Approved with
updated geotech
2- letter 11/1/24,
lr M. Clugston
Reviewer Signature Date
Appeals: Any decision to approve, condition, or deny a development proposal or other activity based on the
requirements of critical area regulations may be appealed according to, and as part of, the appeal procedure, if any,
for the permit or approval involved.
Revised 1112912016
RESU B panGEC)
Oct 252024 INCORPORATED
CITY OF EDMONDS Jeotechnical & Earthquake
DEVELOPMENT SERVICES Engineering Consultants
DEPARTMENT
October 25, 2024
File No. 02-063
Ms. Elana Shippen
18101 Sunset Way,
Edmonds, WA 98026
Subject: Impact Review of Drainage Improvements
Plan Review Comments #4 10/3/2024
Permit Number ENG2022-0536
18101 Sunset Way
Edmonds, Washington
Dear Elana:
As requested, this letter presents our assessment of the proposed drainage improvements at your
house at 18101 Sunset Way in Edmonds, prepared by CG Engineering. This letter is in response
to the City of Edmonds Plan Review #4, dated October 3, 2024.
Item 17: Review #4 10/3/2024 — Comment kept for refence. Provide an update letter as
directed. Ref. Review #3 4/30/2024 and Review #2 12/28/2023. Both stating that updated letters
from the Geotechnical Engineer approving the updated proposed TESC, stormwater management
system and/or ground disturbance.
We have reviewed the updated plans dated October 25, 2024, and, in our opinion, the proposed
TESC measures will adequately protect against the release of soil material from the construction
site. We have also reviewed the proposed stormwater management system and, in our opinion, if
constructed in accordance with design plans, the system will protect critical areas against
uncontrolled release of stormwater or ground disturbance.
Item 1 under the section titled "Specific Comments" requires a letter from the Geotechnical
Engineer addressing the impacts of this specific proposed system to the subject site, as previous
reports addressed systems with different configurations. We have reviewed the current
proposed configuration regarding potential impacts of the drainage improvements on the
Landslide Hazard and Erosion Hazard area identified on your property by the City of Edmonds
in their Critical Area Determination (CRA2022-0115) letter dated August 17, 2022. We have
3414 NE 55 h Street
Seattle, WA 98105
(206)262-0370
Proposal for Geotechnical Engineering Services
18101 Sunset Way, Seattle, WA
October 25, 2024
reviewed CG Engineering's Detention and Drainage plan which shows a 36 inch CMP detention
vault, 31 feet in length, located 8 feet off of and parallel to the lower level patio, and drainage
collection lines for roof and driveway drainage. The outfall from the detention vault will consist
of 58 feet of 6-inch PVC drain line routed to a catch basin located along the eastern property in a
5-foot utility easement, per plan map. Based on the site plans, the closest facility approach to the
steep slope hazard area is at the west end of the retention vault, which is a minimum of 20 feet
from the top of the steep slope area. Accordingly, the proposed improvements do not fall within
the hazard area or the 10-foot buffer area per 23.80.020.13 of the Edmonds Municipal Code.
Based on our boring PG-3, drilled in the area of the planned improvements, the underlying soils
are dense and stable, and the impact of the construction excavations will be minimal. In our
opinion, as long as the improvements are located as shown on CG's plans, the risk of impact to
the Landslide and Erosion Hazard area is low.
Sincerely,
Stephen H. Evans, L.E.G.
Senior Engineering Geologist
W. Paul Grant, P.E.
Principal Geotechnical Engineer
02-063 18101 Sunset Way Drainage Improvements Review 2024-rev 1.doc 2 PanGEI
RESUB
Aug 16 2024
CITY OF EDMONDS
DEVELOPMENT SERVICES
DEPARTMENT
: --- ---------+
Reviewed by
City of Edmonds
Planning Division ;
l--------------'
August 13, 2024
File No. 02-063
Ms. Elana Shippen
18101 Sunset Way
Edmonds, WA 98026
Subject: Geotechnical Engineering & Critical Areas Report
Drainage Improvements
18101 Sunset Way
Edmonds, Washington
Dear Elana,
PmGE0
P O R A T E D
Geotechnical & Earthquake
Engineering Consultants
As requested, PanGEO Inc. completed a geotechnical engineering and critical areas report to
assess the impacts of the planned drainage improvement project at your residence at 18101
Sunset Way on identified potential geological hazardous areas, in accordance with EDCD
23.80.050. Our study was performed as authorized on May 8, 2024. Our scope of work included
reviewing our previous reports for your property, City of Edmonds Correction Notices, and the
civil engineering plans developed by CG Engineering, from which we developed the conclusions
and recommendations presented in this report.
SITE AND PROJECT DESCRIPTION
Your property is located between Sunset Way and Olympic View Drive in Edmonds,
Washington (see Figures 1 and 2). Your one-story house, which has a daylight basement, was
constructed in 1973 on your 0.27-acre parcel. The property is roughly trapezoidal in shape,
oriented with the main axis southwest to northeast (see Figure 2). The site slopes gently down
from Sunset Way to a relatively level backyard area, then slopes steeply down to Olympic View
Drive about 30' below. The northern property boundary is located mid -slope.
3213 Eastlake Avenue East Suite B
Seattle, WA 98102-7127
(206)262-0370
www.pangeoinc.com
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
Based on our review of CG Engineering civil engineering plans , dated 12/06/2023, we
understand that you intend to renovate the existing drainage system at the site, including all roof,
footing and pavement drains. Previously, all drains discharged into the backyard area, some into
drainage pipes with uncertain discharge points, some into pipes that were known to be
obstructed. Renovation plans call for all drains to be collected into a detention system located
approximately 8 feet north of the existing patio slab. The outflow from the 36-inch diameter N-
12 detention pipe will run east through a 6-inch diameter PVC pipe to an existing catch basin
situated on a City of Edmonds storm drain easement that is located along the east property
boundary.
GEOLOGICALLY HAZARDOUS AREAS
The bank along the north side of the property above Olympic View Drive has been identified as
a Geologically Hazardous Area, which has been mapped as a landslide hazard and erosion
hazard area by the City of Edmonds. The limits of the landslide hazard area, with buffer, is
shown on the revised project survey plans, dated 08/12/2024. There does not appear to be any
other hazards with potential to be affected by the project, mapped within 200 feet of the project
area.
SUBSURFACE EXPLORATIONS
Various geotechnical investigations have been conducted for your parcel, including PanGeo's
2018 subsurface investigation that included 3 borings (PG-1 to PG-3) which were drilled at the
locations shown on Figure 2. Two of these borings were drilled using a hand portable, 4-inch
diameter hollow stem auger Acker drilling equipment owned and operated by CN Drilling of
Shoreline, Washington on March 30, 2018. The borings were advanced to depths of 21.5 and
21.0 feet below the existing ground surface, respectively. As the Acker borings encountered
difficult drilling conditions and could not reach the desired depth, a third boring (PG-3) was
drilled on May 24, 2018, using a small track mount RTC 60 drill operated by Boretec, Inc., of
Valleyford, Washington. This boring was advanced to a depth of 35 feet below surface.
An engineering geologist from our firm was present during drilling to field classify and log the
materials recovered from the borings. Soil sampling was conducted in the borings in accordance
with Standard Penetration Test (SPT) split spoon sampling procedures which consist of driving a
2-inch diameter split steel sampler into the soil beyond the auger bit a distance of 18 inches,
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc2 PanGEO
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
using a 140-pound safety hammer falling 30 inches. The hammer was operated using a rope and
cathead pulley mechanism. The number of blows for each 6-inch penetration of the sampler was
recorded. The total number of blows for the last 12 inches of penetration is called the N-value,
which is a relative indicator of the density of granular soils and the consistency of cohesive soils.
Summary logs of the borings are presented in Appendix A. The soils encountered in the borings
were described and field classified in general accordance with the symbols and terms outlined in
Figure A-1, followed by the summary logs in Figures A-2 to A-4.
SUBSURFACE CONDITIONS
SOILS
The Geologic Map of the Edmonds East and part of the Edmonds West Quadrangles (Minard,
1983) shows the surficial geologic units in the area of the site to consist of Vashon Till (Qvt),
Vashon Advanced Outwash (Qva), Transitional Beds (Qtb), and Olympia Gravels (Qog).
Till (Qvt) is characterized as a compact, heterogeneous mix of silt, sand, gravel, clay, cobbles
and boulders, and is very dense where undisturbed. The advanced outwash (Qva) is described as
dense to very dense where undisturbed, well -sorted sand and gravel with silt beds and lenses.
The Transitional beds (Qtb, also called Lawton Clay) are described as very stiff to hard,
laminated to massive, silt and clayey silt. Minard (1983) uses the term "transitional beds" as it
includes non -glacial strata at the base of the unit. The Olympia Gravel (pre -Fraser glaciation)
strata consist of very dense, stratified sand and gravel, that may be locally weakly oxidized.
The site borings did not encounter glacial till, though in PG-3 we did find a thin surficial layer of
loose, red -brown silty sand that is likely a residual melt -out till material. The borings advanced at
the site generally encountered fill or colluvium, underlain by a loose to dense, fine-grained soil
that we interpreted as Transitional Bed strata, overlying medium dense to very dense sand and
gravel which we interpret as Olympia Beds.
The following provides our interpretations of the soil conditions underlying your property. The
subsurface units are graphically depicted in Figure 3 and the location of the profile is shown on
Figure 2.
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc3 PanGEO
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
Fill / Colluvium Deposits: The borings encountered disturbed material at the top of the
slope, which we interpret as fill from the basement excavation. The fill encountered in
borings PG-1 and PG-2 contained layers of loose silt and fine to medium sand. The soil is
characterized by a mixed texture, which contains some organics and occasional angular
soil clasts. The fill also included medium dense, very dark gray to black, silty gravel with
sand which appeared like degraded asphalt, but lacking petroleum odors or other apparent
organic material. While the origin of this material is unknown, it is likely derived from
the excavation for the daylight basement. The fill extends to a depth of approximately 4
feet near the top of the slope.
Transitional Beds: The in -situ native soil consists of medium dense to dense, gray
brown, clayey silt with occasional gravel. The transitional bed extends roughly 14 feet
below the surface at the top of the slope.
Olympia Beds: The deepest unit penetrated consisted of medium dense to very dense,
fine to coarse sand with gravelly beds. The unit varies from laminated to medium bedded
and contains a trace to some silt in the form of a matrix. The unit shows finer grained
and coarser grained bedding and is moderately weathered. Based on the weathering and
the grain size distribution, we interpret this unit as Olympia Beds.
GROUNDWATER
Groundwater was not encountered during drilling, but some thin layers of soil encountered in the
test borings indicated the potential for seasonal perched lenses of water. A standpipe piezometer
was installed in boring PG-3 where a well screen was placed between depths of 20 and 35 feet.
The piezometer was sounded on July 5, 2018, and was found to be dry. Water levels may be
expected to vary seasonally and will be highest in March or April.
Previous experience with the site and our reconnaissance along the base of the bank above
Olympic View Drive has indicated that groundwater seeps are generally absent along Olympic
View Drive.
GEOTECHNICAL EVALUATION OF THE PLANNED PROJECT
To help assess the potential impacts of the planned project on the landslide and erosion hazard
area, we have developed a profile of the interpreted soil conditions showing the relationship
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc4 PanGEO
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
between the drainage project and the slope (see Figure 3). As can be seen in the profile, the
planned retention pipe will be located in the native, medium dense to dense, Transitional Bed
silts, and not within the fill located at the top of the slope. Based on the known landslides along
the bank above Olympic View Drive, including the slide on the subject property in 2016, the
slides are of the shallow colluvial style. As such, when they occur, slides do not cut deeply into
the top of the slopes, but are generally limited to the surficial soils, especially if the surficial soils
are comprised of loose fill. In our opinion the core of the slope is globally stable under current
conditions. In our opinion, a set -back of 15 feet from the top of the geologically hazardous area
is adequate to protect the new detention facility from potential future instability on the slope.
Based on our understanding of subsurface conditions and the proposed drainage improvement
project, we believe that the proposed construction will have no adverse impacts on the
geologically hazardous area, either on the subject property or on adjacent properties, and will not
decrease the stability of the landslide and erosion hazard areas. In addition, in our opinion, based
on the set -back of at least 18 feet from the top of the steep slope, the permanent condition,
including when the detention pipe is full of water, will not adversely impact the slope, or
decrease the stability of the slope. In our opinion the installation of the 6-inch diameter discharge
pipe will also not adversely impact the slope. In fact, as the planned drainage improvements will
control previously uncontrolled stormwater discharge, and as such, will serve as a mitigation
measure to improve the stability of the landslide/erosion hazard area.
Construction Considerations - To limit the volume of material excavated, we suggest that the
excavation be cut vertically with trench boxes to support the excavation walls. Excavated
material that is planned to be reused as fill should be stockpiled upslope of the excavation, at
least 20 feet from the excavation, away from the slope and within the sediment containment area.
If open cuts are used, they should be sloped no steeper than 1H:IV. As can be seen on the profile
(Figure 3), even open cuts are used, the cuts remain outside the anticipated areas underlain by
fill, and will not impinge on the 15-foot set -back. All excess excavated material should be
exported from the site.
CLOSURE
We have prepared this report for your use in renovating the stormwater drainage facilities for
your house. Recommendations contained in this report are based on a review of the civil
engineering plans, a review of the City of Edmonds codes as applied to your project in response
to plan review comments contained in the review letter dated March 28, 2024, a review of
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc5 PanGEO
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
pertinent subsurface information and our past experience with your site, and our understanding
of the project. The study was performed using a mutually agreed -upon scope of work.
Variations in soil conditions may exist at locations away from the explorations and the actual
conditions underlying the site may vary. The nature and extent of soil variations may not be
evident until construction occurs. If any soil conditions are encountered at the site that are
different from those described in this report, we should be notified immediately to review the
applicability of our recommendations. Additionally, we should also be notified to review the
applicability of our recommendations if there are any changes in the project scope.
The scope of our work does not include services related to construction safety precautions. Our
recommendations are not intended to direct the contractors' methods, techniques, sequences or
procedures, except as specifically described in our report for consideration in design.
Additionally, the scope of our work specifically excludes the assessment of environmental
characteristics, particularly those involving hazardous substances.
This report has been prepared for planning and design purposes for specific application to the
proposed project in accordance with the generally accepted standards of local practice at the time
this report was written. No warranty, express or implied, is made.
This report may be used only by the client and for the purposes stated, within a reasonable time
from its issuance. Land use, site conditions (both off and on -site), or other factors including
advances in our understanding of applied science, may change over time and could materially
affect our findings. Therefore, this report should not be relied upon after 24 months from its
issuance. PanGEO should be notified if the project is delayed by more than 24 months from the
date of this report so that we may review the applicability of our conclusions considering the
time lapse.
Any party other than the client who wishes to use this report shall notify PanGEO of such
intended use and for permission to copy this report. Based on the intended use of the report,
PanGEO may require that additional work be performed and that an updated report be reissued.
Noncompliance with any of these requirements will release PanGEO from any liability resulting
from the use this report.
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc6 PanGEO
Elana and Matthew Shippen
Drainage Improvements - 18101 Sunset Way, Edmunds, WA
August 13, 2024
We appreciate the opportunity to be of service.
Sincerely,
PanGEO, Inc.
low 11 001 ��
Stephen H. Evans, L.E.G. W. Paul Grant, P.E.
Senior Engineering Geologist Principal Geotechnical Engineer
Enclosures:
Figure 1 Vicinity Map
Figure 2 Site and Exploration Plan
Figure 3 Generalized Subsurface Profile — Section A -A'
Appendix A — Boring Logs
References
Minard, J.P., 1983, Geologic map of the Edmonds East and Part of the Edmonds West
Quadrangles, Washington, U.S.G.S. Miscellaneous Field Studies Map MF-1541
02-063-18101 Sunset Way Drainage 2024.08.12 - wpg .doc7 PanGEO
02-063 Fig 1 Vicinity.ppt 5/23/2024(11:41 AM) SHE
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EP SLOPE.
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OOFDRAINS INTO - - - - - - RIM:243.36 _
4DTHE FOOTING ---------
- - IE IN (S) 6" PVC: 241.86
2 3 FROM THE �` /--�_ -`„-�-----------IEOUT(NE)6"PVC:238.86
_ _—IE(W)36'N12=238.86 C3. C3. _-
- ------------
- - - __
el DETENTION / / / / _ - -_ -_ \-
C3. 31L` _ _ - F-36"N12 %/ / _' ~\ \� \7
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AFN 196o
27041800202100 / / 4 �- AFN 20:8755
DETENTION ACCESS, A r'G-1
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SE EXISTING YARD DRAIN f03 SF 12 C1, I CONTRACTION
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CONCRETE SLAB AT END ��4 ST NO REBAR W/CAP FROM
GM -
EXISTING PARKING AREA // Q' LINE / IE 12*RCP(N)-23506
DRAINAGE AND TIE INTO /?4¢- --- CONTRACTOR TO VERIFY
DETENTION SYSTEM �• / E 12CY #WEFT & R%V
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2' REBAR i ' CONDITION OF CB Al
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BE VERIFIED BY CONI
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v Approximate Scale LEGEND:
1":30'
PG Location of Borings
3 AND DRAINAGE PLAN
^E® Drainage Improvements
p
(`7' 18101 Sunset Way SITE AND EXPLORATION PLAN
Edmonds, Washington
I N C O R P O R A IT D
Project No. Figure No.
02-063 2
A
Proposed
Top of Landslide/
250
36" Detention Tank
Erosion Hazard Area
House per Civil Drawings,
invert el. 238.19'
i 15' Buffer
PG-3
```
PG-2
Loose Red -Br
1 H:1 V Excavation
240
silty SAND
,' — -
Loose SILT
5
Transitional Beds
\ & sA"°
_ _ _ ,'
sm boulder 50/4
MD to Dense D GRAV
clayey SILT, w/ silt�sa d
32 FILL
_
.�
sand/grav beds
_
�
5
Loose to MD
Dense, brn gray,
SILT, NP to Slt P
�` Occ tr sand
8
f to c SAND 31
230
with gravel Olympia Beds
�
15 O
Dense, gray
NP-Slt P 32
2i
SILT, tr sand
62
Dense to VD
f to c SAND
71
some g & silt
220
52
a)
VD, It brn,
C
f to m SAND
�..�
tr silt 41
C
(6
>
50/5
a)
210
Note: Piezometer
screened 20 - 35'
dry on July 5, 2018
50/6
200-
r
190-
o
0 180-J
Graphics Legend:
BH-1
Topographic Surface
Groundwater Seep
Groundwater
Level z$ SP N-value
_ so
Soil Unit �f $$
Boundries 31
——— --_42—————
31
M 0 10 20
h
V
J
Notes:
= 1. Site topography based on survey data provided
by Newport West LLC.
2. Elevations based on NAVD 88.
D
J
V
J
30 40 50 60 70
Distance (ft.)
Olympic View Drive
80 90 100 110 120 130
A'
r— 250
- 240
- 230
220 a)
a)
C
C
O
- 210-2
- 200
- 190
- 180
APPENDIX A
BORING LOGS
Project: Landslide Remediation
Surface Elevation:
Job Number: 02-063
Top of Casing Elev.:
Location: 18101 Sunset Way, Edmonds, WA
Drilling Method: HSA
Coordinates: Northing: , Easting:
Sampling Method: SPT
$
CL
0
O
Z
C1
Co
Q
C
(n
m
L
a)
O
o
E
MATERIAL DESCRIPTION
N-Value A
PL Moisture ILL
ROD Recovery
®EJ
0 50 100
0
3
Loose, brown SILT: moist, some fine sand, non -plastic to slightly
S-1
3
plastic, mottled, occasional angular soil clasts, mixed. (Fill /
4
Colluvium).
.........
.........
.........
.........
1
Trace to some fine sand, slightly plastic, no dilatancy, occasional
........
........
........
.........
.........
.........
S-2X
1
charcoal, gravel.
3
5
2
Medium stiff, gray and brown, clayey SILT: moist, low plastic, slow to
S-3X
5
no dilatancy, homogeneous, laminated. (Transitional Beds).
5
Medium dense, brown gray SILT with fine sand: moist, non -plastic
5
homogeneous, rusty veins and mottles, laminated. (Transitional
S-4
6
Beds).
6
10
5
Medium dense to dense, brown gray, interbedded, fine to medium
SAND and SILT: moist, generally non -plastic silt, fine bedded to
S-5
9
laminated, beds 4 to 6 inches, rusty bands along contacts.
9
(Transitional Beds).
One low plastic, silt lean CLAY interbed.
6
Rusty bands.
S-6
14
15
15
S-7
10
20
29
Dense to very dense, light brown to rusty brown, fine to coarse SAND:
moist, trace to some silt, trace fine, tabular gravel, finer / coarser
layering, slightly rusty bands and laminae, moderately weathered,
laminated. (Olympia Gravel).
20
27
Becoming very moist, beds 4 to 6 inches, silt interbed at 21.3 feet.
S-8
37
32
Bottom of Boring.
25
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
Completion Depth: 21.5ft
Remarks: No groundwater encountered during drilling.
Date Borehole Started: 3/30/18
Date Borehole Completed: 3/30/18
Logged By: S. Evans
Drilling Company: CN Drilling
FbnGEO LOG OF TEST BORING PG-1
I N C O R P G R A T E D Figure A-2
The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 Of
Project: Landslide Remediation
Surface Elevation:
Job Number: 02-063
Top of Casing Elev.:
Location: 18101 Sunset Way, Edmonds, WA
Drilling Method: HSA
Coordinates: Northing: , Easting:
Sampling Method: SPT
$
CL
0
O
Z
C1
Co
Q
C
(n
m
L
a)
O
o
E
MATERIAL DESCRIPTION
N-Value A
PL Moisture LL
ROD Recovery
®EJ
0 50 100
0
Loose, brown to brown gray, inter -layered SILT and fine to medium
S-1
2
SAND: moist, non -plastic to slightly plastic, occasional gravel, mixed
3
texture. (Fill).
S-2
9
12
11
Medium dense, dark gray, silty GRAVEL with sand: moist, occasional
brown layer, gravel sub -rounded, tabular to prismatic, homogeneous,
layered. (Fill).
0 o
.........
.........
5
2
Loose, light brown gray SILT: moist to very moist, non -plastic,
homogeneous, laminated, with rusty swirls. (Transitional Beds).
S-3
2
3
.........
.........
.........
.........
.........
.........
.........
.........
2
Becoming light green gray, non -plastic to slightly plastic, rusty bands,
.........
.........
.........
.........
.........
.........
S-4
4
finely fractured at 8.5 feet, micaceous.
4
.
. . . . . . . . .
10
5
Gray and rusty brown, trace fine sand, slightly plastic with slow to rapid
......
.........
S-5
6
dilatancy, rusty fractures and bands, some sharp bedding contacts.
9
.........
... .....
... .....
.........
.........
.........
4
Light green gray SILT occasional sandy laminae.
.........
.........
.........
.........
.........
.........
15
S-6
11
15
14
.... ....
.........
a
e
e
Medium dense to very dense, brown gray, fine to coarse SAND: moist,
some gravel and silt, massive to indistinctly laminated and bedded,
moderately weathered with rusty staining. (Olympia Gravel).
Fine to coarse SAND with gravel, gravel sub -angular and blocky to
S-7
32
tabular, massive.
30
20
S-8X
16
26
Rusty brown, fine to coarse SAND, scattered gravel, slightly to
moderately weathered, laminated to massive.
26
Bottom of Boring.
25
.........
.........
.........
.........
.........
.........
.........
.........
.........
.........
Completion Depth: 21.Oft
Remarks: No groundwater encountered during drilling.
Date Borehole Started: 3/30/18
Date Borehole Completed: 3/30/18
Logged By: S. Evans
Drilling Company: CN Drilling
FbnGEO LOG OF TEST BORING PG-2
I N C O R P G R A T E D Figure A-3
The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 Of
Project: Landslide Remediation
Job Number: 02-063
Location: 18101 Sunset Way, Edmonds, WA
Coordinates: Northing: , Easting:
o
(D
C
F
i
N
Q
Q
(n
L
E
C
M
^
V,
M
L J
O
0
`[I
15
20
25
Surface Elevation:
Top of Casing Elev.:
Drilling Method:
Sampling Method:
MATERIAL DESCRIPTION
HSA
SPT
N-Value A
PL Moisture LL a0i
1 I E
® RQD Recovery ® c
0 50 100
Loose, red brown, silty, fine SAND with gravel: moist.
(Ablation Till).
Medium dense to dense, gray, clayey SILT with fine sand:
moist, gravelly and sandy interbeds. (Transitional Beds).
S-1
Z
50/4
Small boulder, blow counts at 5 feet unreliable.
>
1
>
>
Dense, speckled brown gray, fine to coarse SAND with
gravel: slightly moist, some silt, layered, moderately
weathered, gravel sub -rounded and blocky, some coarse
S-2
X4
19
grained granitic gravels. (Olympia Gravels).
12
<
Sample tube at 15 wet, sample moist, likely perched water
around 13 feet. ----------------- J
`-------
. . .
.........
. . :
.........
S-3
$
15
17
Dense, brown gray SILT: moist, non -plastic to slightly
plastic, occasional rusty pockets, trace fine sand and sandy
laminae, scattered gravel, laminated with dips to 10°.
(Olympia Gravels).
.........
....... .
....... .
.........
.........
.........
.........
.........
.........
.........
Very dense, light brown, fine to medium SAND: moist, fine
.........
.........
.........
.........
to coarse interbeds, homogeneous,trace to some
non -plastic silt, slightly weathered. (Olympia Gravels).
13
S-4
26
MEN
45
20
Brown, fine to medium SAND, wet gray bed at top,
S-5
26
1
laminatedpossible perched water layer at 20 feet.
Completion Depth: 36.0ft Remarks: No significant groundwater encountered during drilling. Two thin perched water
Date Borehole Started: 5/24/18 lenses observed.
Date Borehole Completed: 5/24/18
Logged By: S. Evans
Drilling Company: CN Drilling
C_1T7® LOG OF TEST BORING PG-3
I N C O R P O R A T E D Figure A-4
The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 2
Project: Landslide Remediation
Surface Elevation:
Job Number: 02-063
Top of Casing Elev.:
Location: 18101 Sunset Way, Edmonds, WA
Drilling Method: HSA
Coordinates: Northing: , Easting:
Sampling Method: SPT
N-Value A
O
Z
o
PL Moisture ILL
Q
~
E
MATERIAL DESCRIPTION
CL
0
Co
�
El Recovery ®
c
m
O
0 50 100
Very dense, light brown, fine to medium SAND: moist, fine
to coarse interbeds, homogeneous,trace to some
non -plastic silt, slightly weathered. (Olympia Gravels).
(Continued)
30
31
Light brown sand with gray bed at top above a thin silt bed,
S-6
47
slightly weathered, graded bedding with 6 inch beds.
50/5
35
S-7
36
Light brown, fine to medium SAND, homogeneous, moist,
50/6
trace to some silt.
Bottom of Boring.
40
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45
.........
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.........
50
.........
.........
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Completion Depth: 36.Oft
Remarks: No significant groundwater encountered during drilling. Two thin perched water
Date Borehole Started: 5/24/18
lenses observed.
Date Borehole Completed: 5/24/18
Logged By: S. Evans
Drilling Company: CN Drilling
LOG OF TEST BORING PG-3
PmGE@)
I N C O R P G R A T E D Figure A-4
The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 2 Of 2