RESUB1 BLD2023-0168+GEO REPORT+8.16.2023_5.20.23_PM+3730668RESUB BLD2023-0168
Aug 17 2023
CITY OF EDMONDS
DEVELOPMENT SERVICES
DEPARTMENT
Cobalt Geosciences, LLC
COBALT
GEOSCIE P.O. Box1792
North Bend, WA 98045
August 15, 2023
Sofia Bolotin
sofikland (&_gmail. com
RE: Geotechnical Evaluation
Proposed Additions
18230 gist Avenue West
Edmonds, Washington
In accordance with your authorization, Cobalt Geosciences, LLC has prepared this letter to
discuss the results of our geotechnical evaluation at the referenced site.
Site and Project Description
The site is located at 18230 gist Avenue West in Edmonds, Washington. The site consists of one
irregularly shaped parcel (No. 27041800200300) with a total area of about 0.59 acres.
The central oprtion of the site is developed with a single family residence with daylight basement
and driveway. There are rockery and other short walls within the property and near some
property lines. Overall, the site slopes downward from southeast to northwest and west at
magnitudes of 5 to slightly over 15 percent and relief of about 25 feet. The site is vegetated with
grasses, bushes, shrubs, and local trees.
The site is bordered on all sides by residential properties with access from the southeast corner of
the site along a shared easement.
The project includes additions to the existing residence and likely modifications to stormwater
systems, local wall construction and possible landscaping. The site contains erosion hazard areas
per City of Edmonds municipal code.
Site grading may include cuts and fills of 3 feet or less, and foundation loads are expected to be
light. We have reviewed civil plans by Wesi Land Use Consultants dated July 11, 2023. These
indicate that stormwater will be managed through dispersion devices, splash blocks, vegetated
flowpaths, and local sheet flow dispersion.
Area Geology
The Geologic Map of the Edmonds East and West Quadrangles, indicates that the site is underlain
by Vashon Glacial Till.
Vashon Glacial Till includes mixtures of silt, sand, clay, and gravel. These materials are usually
impermeable and are typically dense to very dense below a weathered zone.
Soil & Groundwater Conditions
As part of our evaluation, we observed excavation of two test pits within the property areas, where
accessible.
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Geotechnical Evaluation
The test pits encountered approximately 6 inches of grass and topsoil underlain by approximately
3.25 feet of loose to medium dense, silty -fine to medium grained sand with gravel (Weathered
Glacial Till). These materials were underlain by dense to very dense, silty -fine to medium grained
sand trace to with gravel (Vashon Glacial Till), which continued to the termination depths of the
explorations.
Groundwater was not encountered during the exploration work. There is a chance that perched
groundwater may develop on the denser till during the wet season. Groundwater could be 4 to 10
feet below site elevations, if present.
Water table elevations often fluctuate over time. The groundwater level will depend on a variety
of factors that may include seasonal precipitation, irrigation, land use, climatic conditions and
soil permeability. Water levels at the time of the field investigation may be different from those
encountered during the construction phase of the project.
Erosion Hazard Areas
The site contains erosion hazard areas per City of Edmonds mapping. Local areas have
magnitudes of 15 percent or more and underlain by Alderwood sandy gravelly loam which can
have erosion potential when exposed.
Code Information
23.80.o6o Development standards — General requirements.
A. Alterations of geologically hazardous areas or associated buffers may only occur for activities
that:
1. Will not increase the threat of the geological hazard to adjacent properties beyond
predevelopment conditions;
2. Will not adversely impact other critical areas;
3. Are designed so that the hazard to the project is eliminated or mitigated to a level equal to or
less than predevelopment conditions; and
4. Are certified as safe as designed and under anticipated conditions by a qualified engineer or
geologist, licensed in the state of Washington.
The currently_ proposed project includes additions to the residence, which will require foundation
excavation work. Additional construction includes new walls, driveway modifications, and
stormwater systems. Most work will require minimal grading.
It is our opinion that the project can be completed without adversely affecting erosion hazards
provided work is monitored by the geotechnical engineer and erosion control measures are in
place during construction.
The proposed construction will not increase the threat of geologic hazards on adjacent proper -ties,
will not impact other critical areas, and are safe as designed under anticipated conditions.
23.80.07o Development standards — Specific hazards.
A. Erosion and Landslide Hazard Areas. Activities on sites containing erosion or landslide
hazards shall meet the requirements of ECDC 22.80.o6o, Development standards — General
requirements, and the specific following requirements:
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Geotechnical Evaluation
1. Minimum Building Setback. The minimum setback shall be the distance required to ensure the
proposed structure will not be at risk from landslides for the life of the structure, considered to be
120 years, and will not cause an increased risk of landslides taking place on or off the site. A
setback shall be established from all edges of landslide hazard areas. The size of the setback shall
be determined by the director consistent with recommendations provided in the geotechnical
report to eliminate or minimize the risk of property damage, death, or injury resulting from
landslides caused in whole or part by the development, based upon review of and concurrence
with a critical areas report prepared by a qualified professional;
Not applicable.
2. Buffer Requirements. A buffer may be established with specific requirements and limitations,
including but not limited to, drainage, grading, irrigation, and vegetation. Buffer requirements
shall be determined by the director consistent with recommendations provided in the
geotechnical report to eliminate or minimize the risk of property damage, death, or injury
resulting from landslides caused in whole or part by activities within the buffer area, based upon
review of and concurrence with a critical areas report prepared by a qualified professional;
Not required for erosion hazard areas.
3. Alterations. Alterations of an erosion or landslide hazard area, minimum building setback
and/or buffer may only occur for activities for which a hazards analysis is submitted and certifies
that:
a. The alteration will not increase surface water discharge or sedimentation to adjacent properties
beyond predevelopment conditions;
b. The alteration will not decrease slope stability on adjacent properties; and
c. Such alterations will not adversely impact other critical areas;
Provided earthwork activities are performed in accordance with the approved plans, all runoff is
fully controlled, and periodic geotechnical oversight is performed, the development will not
increase surface water discharge or sedimentation beyond current levels, and will not impact
other critical areas. Temporary and permanent erosion and sediment control devices should be in
at all times during construction.
4. Design Standards within Erosion and Landslide Hazard Areas. Development within an erosion
or landslide hazard area and/or buffer shall be designed to meet the following basic requirements
unless it can be demonstrated that an alternative design that deviates from one or more of these
standards provides greater long-term slope stability while meeting all other provisions of this
title. The requirement for long-term slope stability shall exclude designs that require regular and
periodic maintenance to maintain their level of function. The basic development design standards
are:
a. The proposed development shall not decrease the factor of safety for landslide occurrences
below the limits of 1.5 for static conditions and 1.2 for dynamic conditions. If stability at the
proposed development site is below these limits, the proposed development shall provide
practicable approaches to reduce risk to human safety and improve the factor of safety for
landsliding. In no case shall the existing factor of safety be reduced for the subject property or
adjacent properties;
b. Structures and improvements shall be clustered to avoid geologically hazardous areas and
other critical areas;
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Geotechnical Evaluation
c. Structures and improvements shall minimize alterations to the natural contour of the slope,
and foundations shall be tiered where possible to conform to existing topography;
d. Structures and improvements shall be located to preserve the most critical portion of the site
and its natural landforms and vegetation;
e. The proposed development shall not result in greater risk or a need for increased buffers on
neighboring properties;
f. The use of retaining walls that allow the maintenance of existing natural slope area is preferred
over graded artificial slopes; and
g. Development shall be designed to minimize impervious lot coverage;
Not applicable. Provided temporary erosion control systems are in place during construction, no
increased risk to geologic hazards will occur on the property or adjacent areas. No specific buffers
or setbacks from erosion hazard areas are required.
5. Vegetation Retention. Unless otherwise provided or as part of an approved alteration, removal
of vegetation from an erosion or landslide hazard area or related buffer shall be prohibited;
6. Seasonal Restriction. Clearing shall be allowed only from May ist to October ist of each year;
provided, that the director may extend or shorten the dry season on a case -by -case basis
depending on actual weather conditions, except that timber harvest, not including brush clearing
or stump removal, may be allowed pursuant to an approved forest practice permit issued by the
city of Edmonds or the Washington State Department of Natural Resources;
7. Point Discharges. Point discharges from surface water facilities and roof drains onto or
upstream from an erosion or landslide hazard area shall be prohibited except as follows:
a. Conveyed via continuous storm pipe downslope to a point where there are no erosion hazard
areas downstream from the discharge;
b. Discharged at flow durations matching predeveloped conditions, with adequate energy
dissipation, into existing channels that previously conveyed storm water runoff in the
predeveloped state; or
c. Dispersed discharge upslope of the steep slope onto a low -gradient, undisturbed buffer
demonstrated to be adequate to infiltrate all surface and storm water runoff, and where it can be
demonstrated that such discharge will not increase the saturation of the slope; and
We concur with the above code items and have no additional comments at this time. Dispersion
systems appear suitable at this site even though some areas have magnitudes slightly over 1.ri
percent. This can be implemented without adverselv affecting geologic hazards.
Erosion Hazard
The Natural Resources Conservation Services (NRCS) maps for Snohomish County indicate that
the site is underlain by Alderwood Urban land complex (8 to 15 percent slopes) and Alderwood
gravelly sandy loam (15 to 25 percent slopes). These soils would have a moderate to severe
erosion potential in a disturbed state depending on the slope magnitude.
It is our opinion that soil erosion potential at this project site can be reduced through landscaping
and surface water runoff control. Typically, erosion of exposed soils will be most noticeable
during periods of rainfall and may be controlled by the use of normal temporary erosion control
measures, such as silt fences, hay bales, mulching, control ditches and diversion trenches.
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Geotechnical Evaluation
The typical wet weather season, with regard to site grading, is from October ist to April 31st.
Erosion control measures should be in place before the onset of wet weather.
Conclusions and Recommendations
General
The site is underlain by soils consistent with Vashon Glacial Till. These soils become denser with
depth below a weathered zone. It is our opinion that the risk of erosion can be maintained at a
very low level with proper installation and maintenance of temporary erosion control devices
(Best Management Practices (BMPs)).
Upon completion of the grading and earthwork required for the new additions and stormwater
systems, permanent landscaping should be installed. Once properly landscaped with surface
materials and plants, temporary systems may be removed.
Temporary erosion control should include silt fences, wattles, and straw; along with plastic to
cover any soil stockpiles. This type of project will not likely require diversion systems, check
dams, hydroseed or jute mats. We can provide additional input upon request. All temporary
systems must be installed prior to grading.
We performed a small scale infiltration test in TP-1 about 4 feet below grade. The measured
infiltration rate was about 0.5 inches per hour. Upon application of correction factors, the
infiltration rate of the glacial till is lower than what is feasible. This confirms that dispersion
sytesms (as proposed) are the most suitable method for management.
Site Preparation
Trees, shrubs and other vegetation should be removed prior to stripping of surficial organic -rich
soil and fill. Based on observations from the site investigation program, it is anticipated that the
stripping depth will be 6 to 18 inches. Deeper excavations will be necessary below larger trees,
foundation systems, and in any areas underlain by undocumented fill.
The native soils consist of silty -sand with gravel and poorly graded sand. The poorly graded
sands and native soils are likely suitable for use as fill provided all debris and organic materials
are removed. These soils may be used as structural fill provided they achieve compaction
requirements and are within 3 percent of the optimum moisture.
Some of these soils may only be suitable for use as fill during the summer months, as they will be
above the optimum moisture levels in their current state. These soils are variably moisture
sensitive and may degrade during periods of wet weather and under equipment traffic.
Imported structural fill should consist of a sand and gravel mixture with a maximum grain size of
3 inches and less than 5 percent fines (material passing the U.S. Standard No. 200 Sieve).
Structural fill should be placed in maximum lift thicknesses of 12 inches and should be compacted
to a minimum of 95 percent of the modified proctor maximum dry density, as determined by the
ASTM D 1557 test method.
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Geotechnical Evaluation
Stormwater Management Feasibility
The site is underlain by Vashon Glacial Till. These soils become denser with depth below a
weathered zone. The dense till acts as an aquitard. Infiltration is not typically feasible or
recommended in glacial till soils.
The design infiltration rate was determined by applying correction factors to the observed
infiltration rate as prescribed in Volume III, Section 3.3.6 of the DOE. The observed rate must be
reduced through appropriate correction factors for site variability (CFv), uncertainty of test
method (CFT), and degree of influent control (CFM) to prevent siltation and bio-buildup.
It should be noted that construction traffic or other disturbance to the target infiltration area
could compact the soil, which may decrease the effective infiltration rates. The correction factors
and resulting design infiltration rate are also shown in the table below.
Test Pit
Sample
Observed
Correction Factors
Design
Number
Depth (ft)
Infiltration
Infiltration
Rate (in/hr)
Rate
CFv
CFT
CFM
(in/hr)
TP-1
4
0.5
0.9
0.5
0.9
0.20
Infiltration is not feasible in the denser glacial till materials. Dispersion systems as proposed are
feasible and suitable provided all areas are prepared per plan. Flowpaths may be located in areas
with magnitudes of 20 percent or less.
We should be provided with final plans for review to determine if the intent of our
recommendations has been incorporated or if additional modifications are needed.
Erosion and Sediment Control
Erosion and sediment control (ESC) is used to reduce the transportation of eroded sediment to
wetlands, streams, lakes, drainage systems, and adjacent properties. Erosion and sediment
control measures should be implemented, and these measures should be in general accordance
with local regulations. At a minimum, the following basic recommendations should be
incorporated into the design of the erosion and sediment control features for the site:
• Schedule the soil, foundation, utility, and other work requiring excavation or the disturbance
of the site soils, to take place during the dry season (generally May through September).
However, provided precautions are taken using Best Management Practices (BMP's), grading
activities can be completed during the wet season (generally October through April).
• All site work should be completed and stabilized as quickly as possible.
• Additional perimeter erosion and sediment control features may be required to reduce the
possibility of sediment entering the surface water. This may include additional silt fences, silt
fences with a higher Apparent Opening Size (AOS), construction of a berm, or other filtration
systems.
• Any runoff generated by dewatering discharge should be treated through construction of a
sediment trap if there is sufficient space. If space is limited other filtration methods will need
to be incorporated.
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Page 7 of 8
Geotechnical Evaluation
CONSTRUCTION FIELD REVIEWS
Cobalt Geosciences should be retained to provide part time field review during construction in
order to verify that the soil conditions encountered are consistent with our design assumptions
and that the intent of our recommendations is being met. This will require field and engineering
review to:
■ Verify erosion control system suitability
Geotechnical design services should also be anticipated during the subsequent final design phase
to support the structural design and address specific issues arising during this phase. Field and
engineering review services will also be required during the construction phase in order to
provide a Final Letter for the project.
CLOSURE
This report was prepared for the exclusive use of Sofia Bolotin appointed consultants. Any use of
this report or the material contained herein by third parties, or for other than the intended
purpose, should first be approved in writing by Cobalt Geosciences, LLC.
The recommendations contained in this report are based on assumed continuity of soils with
those of our test holes and assumed structural loads. Cobalt Geosciences should be provided with
final architectural and civil drawings when they become available in order that we may review our
design recommendations and advise of any revisions, if necessary.
Use of this report is subject to the Statement of General Conditions provided in Appendix A. It is
the responsibility of Sofia Bolotin who is identified as "the Client" within the Statement of General
Conditions, and its agents to review the conditions and to notify Cobalt Geosciences should any of
these not be satisfied.
Sincerely,
Cobalt Geosciences, LLC
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8/15/2023
Phil Haberman, PE, LG, LEG
Principal
PHIL P HAHi l d
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August 15, 2023
Page 8 of 8
Geotechnical Evaluation
Statement of General Conditions
USE OF THIS REPORT: This report has been prepared for the sole benefit of the Client or its
agent and may not be used by any third party without the express written consent of Cobalt
Geosciences and the Client. Any use which a third party makes of this report is the responsibility
of such third parry.
BASIS OF THE REPORT: The information, opinions, and/or recommendations made in this
report are in accordance with Cobalt Geosciences present understanding of the site specific
project as described by the Client. The applicability of these is restricted to the site conditions
encountered at the time of the investigation or study. If the proposed site specific project differs
or is modified from what is described in this report or if the site conditions are altered, this report
is no longer valid unless Cobalt Geosciences is requested by the Client to review and revise the
report to reflect the differing or modified project specifics and/or the altered site conditions.
STANDARD OF CARE: Preparation of this report, and all associated work, was carried out in
accordance with the normally accepted standard of care in the state of execution for the specific
professional service provided to the Client. No other warranty is made.
INTERPRETATION OF SITE CONDITIONS: Soil, rock, or other material descriptions, and
statements regarding their condition, made in this report are based on site conditions
encountered by Cobalt Geosciences at the time of the work and at the specific testing and/or
sampling locations. Classifications and statements of condition have been made in accordance
with normally accepted practices which are judgmental in nature; no specific description should
be considered exact, but rather reflective of the anticipated material behavior. Extrapolation of in
situ conditions can only be made to some limited extent beyond the sampling or test points. The
extent depends on variability of the soil, rock and groundwater conditions as influenced by
geological processes, construction activity, and site use.
VARYING OR UNEXPECTED CONDITIONS: Should any site or subsurface conditions be
encountered that are different from those described in this report or encountered at the test
locations, Cobalt Geosciences must be notified immediately to assess if the varying or unexpected
conditions are substantial and if reassessments of the report conclusions or recommendations are
required. Cobalt Geosciences will not be responsible to any parry for damages incurred as a result
of failing to notify Cobalt Geosciences that differing site or sub -surface conditions are present
upon becoming aware of such conditions.
PLANNING, DESIGN, OR CONSTRUCTION: Development or design plans and
specifications should be reviewed by Cobalt Geosciences, sufficiently ahead of initiating the next
project stage (property acquisition, tender, construction, etc), to confirm that this report
completely addresses the elaborated project specifics and that the contents of this report have
been properly interpreted. Specialty quality assurance services (field observations and testing)
during construction are a necessary part of the evaluation of sub -subsurface conditions and site
preparation works. Site work relating to the recommendations included in this report should only
be carried out in the presence of a qualified geotechnical engineer; Cobalt Geosciences cannot be
responsible for site work carried out without being present.
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TP-i
N
Approximate
Test Pit
Location
A
Not to Scale
Cobalt Geosciences, LLC
Proposed Additions
SITE MAP
P.O. Box 82243
COBALT(206)
18230 gist Avenue West
Edmonds, Washington
Kenmore, WA 98028
GEOSCIENCES
FIGURE 1
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Slab on Grade
Basement or Shallow Foundation Wall
12" Free Draining Backfill and/or Drainage Mat
Attached to Wall
Backfill Soils Compacted
per Geotechnical Report
4" Diameter Perforated Pipe
-- --�H H
Native Soils Benched
as Required
Filter Fabric Over Rock
(Mirafi 14oN)
3//4" Washed Rock or
Clean Angular Rock
Not to Scale
Cobalt Geosciences, LLC
PO Box 1792
Typical Foundation Drain Detail Attachment North Bend, WA 98045
• _ (2o6) 331-1097
GEOSCIENCES www.cobaltgeo.com
Philpcobaltgeo.com
Unified Soil Classification System (USCS)
MAJOR DIVISIONS
SYMBOL
TYPICAL DESCRIPTION
Clean Gravels
Gw
Well -graded gravels, gravels, gravel -sand mixtures, little or no fines
Gravels
(more than 50%
(less than 5%
fines)
GP
Poorly graded gravels, gravel -sand mixtures, little or no fines
COARSE
GRAINED
SOILS
of coarse fraction
retained on No. 4
sieve)
Gravels with
Fines
(more than 12%
fines)
GM
Silty gravels, gravel -sand -silt mixtures
GC
Clayey gravels, gravel -sand -clay mixtures
(more than 50%
retained on
Clean Sands
:•: sw
Well -graded sands, gravelly sands, little or no fines
No. 200 sieve)
Sands
(50% or more
of coarse fraction
(less than 5%
fines)
sP
Poorly graded sand, gravelly sands, little or no fines
passes the No. 4
sieve)
Sands with
Fines
sM
Silty sands, sand -silt mixtures
(more than 12%
fines)
sc
Clayey sands, sand -clay mixtures
ML
Inorganic silts of low to medium plasticity, sandy silts, gravelly silts,
FINE GRAINED
(50% or more
Silts and Clays
(liquid limit less
than 50)
Inorganic
cL
or clayey silts with slight plasticity
Inorganic clays of low to medium plasticity, gravelly clays, sandy clays
silty clays, lean clays
Organic rganic
oL
Organic silts and organic silty clays of low plasticity
passes the
MH
Inorganic silts, micaceous or diatomaceous fine sands or silty soils,
No. 200 sieve)
Silts and Clays
(liquid limit 50 or
more)
Inorganic
elastic silt
CH
Inorganic clays of medium to high plasticity, sandy fat clay,
or gravelly fat clay
Organic
OHOrganic
clays of medium to high plasticity, organic silts
HIGHLY ORGANIC
SOILS
Primarily organic matter, dark in color,
and organic odor
PT
Peat, humus, swamp soils with high organic content (ASTM D4427)
Classification of Soil Constituents
MAJOR constituents compose more than 50 percent,
by weight, of the soil. Major constituents are capitalized
(i.e., SAND).
Minor constituents compose 12 to 50 percent of the soil
and precede the major constituents (i.e., silty SAND).
Minor constituents preceded by "slightly" compose
5 to 12 percent of the soil (i.e., slightly silty SAND).
Trace constituents compose o to 5 percent of the soil
(i.e., slightly silty SAND, trace gravel).
Relative Density
(Coarse Grained Soils)
Consistency
(Fine Grained Soils)
N, SPT,
Relative
N, SPT,
Relative
Blows/FT
Density
Blows/FT
Consistency
0-4
Very loose
Under 2
Very soft
4 -10
Loose
2-4
Soft
10 - 30
Medium dense
4-8
Medium stiff
30 - 50
Dense
8 -15
Stiff
Over 50
Very dense
15 - 30
Very stiff
Over 3o
Hard
Grain Size Definitions
Description
Sieve Number and/or Size
Fines
<#200 (o.o8 mm)
Sand
-Fine
#200 to #40 (o.o8 to 0.4 mm)
-Medium
#40 to #10 (0.4 to 2 mm)
-Coarse
#10 to #4 (2 to 5 mm)
Gravel
-Fine
#4 to 3/4 inch (5 to 19 mm)
-Coarse
3/4 to 3 inches (19 to 76 mm)
Cobbles
3 to 12 inches (75 to 305 mm)
Boulders
>12 inches (305 mm)
1 Moisture Content Definitions 1
Dry Absence of moisture, dusty, dry to the touch
Moist Damp but no visible water
Wet Visible free water, from below water table
Cobalt Geosciences, LLC
P.O. Box 82243
Kenmore, WA 98028
Soil Classification Chart
Figure Ci
(2o6) 331-1097
_
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Test Pit TP-1
Date: August 2023
Depth: 5'
Groundwater: None
Contractor: Client
Elevation: N/A
Logged By: PH Checked By: SC
--
a)
U)
0Q
o
Moisture Content (%)
Plastic Liquid
U
N
Limit Limit
}
Q
0
L
N
Material Description
o
c
G
?
o
DCP Equivalent N-Value
G
0 10 20 30 40 50
SM
Loose to medium dense, silty -fine to medium grained sand with gravel
1
reddish brown to yellowish brown, dry.
(Weathered Glacial Till)
2
3
--
SM
--------------------------------------------
Dense to — very dense, silty -fine to medium grained sand with gravel,
------
4
----
grayish brown, moist. (Glacial Till) Cemented till
End of Test Pit 5'
6
7
8
9
10
Proposed Additions
18230 gist Avenue West
Edmonds, Washington
Test Pit
Logs
Cobalt Geosciences, LLC
P.O. Box 82243
Kenmore, WA 98028
(2o6) 331-1097
www.cobaltgeo.com
cobaltgeo@gmail.com
Test Pit TP-2
Date: August 2023
Depth: 5'
Groundwater: None
Contractor: Client
Elevation: N/A
Logged By: PH Checked By: SC
--
a)
U)
0Q
o
Moisture Content (%)
Plastic Liquid
U
N
Limit Limit
}
Q
0
L
N
Material Description
o
c
G
?
o
DCP Equivalent N-Value
G
0 10 20 30 40 50
SM
Loose to medium dense, silty -fine to medium grained sand with gravel
1
reddish brown to yellowish brown, dry.
(Weathered Glacial Till)
2
3
--
SM
--------------------------------------------
Dense to — very dense, silty -fine to medium grained sand with gravel,
------
4
----
grayish brown, moist. (Glacial Till) Cemented till
End of Test Pit 5'
6
7
8
9
10
Proposed Additions
18230 gist Avenue West
Edmonds, Washington
Test Pit
Logs
Cobalt Geosciences, LLC
P.O. Box 82243
Kenmore, WA 98028
(2o6) 331-1097
www.cobaltgeo.com
cobaltgeo@gmail.com