REVIEWED RESUB 2 BLD2021-1646+Geotechnical_Report+6.30.2022_2.18.31_PM+2964943RESUB BLD2021-1646
Jul 01 2022
CITY OF EDMONDS
DEVELOPMENT SERVICES G E O T E C H N I C A L ENGINEERING REPORT
DEPARTMENT
REVISION 2
APOLLO APARTMENTS
23601 Highway 99
EDMONDS, WASHINGTON
Project No. 2361.01
April 22, 2022
Prepared for:
Blackfish Capital, LLC
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Prepared by:
ZipperGeo
Geoprofessional Consultants
19019 36th Ave West, Suite E I Lynnwood, WA 98036 1 Phone: 425.582.9928 1 zippergeo.com
Zipp Geo
Geoprofessional Consultants
Project Number 2361.01
April 22, 2022
Blackfish Capital LLC
2442 Market Street NW, #562
Seattle, WA 98107
Attention: Mr. Johnny Vong
Subject: Geotechnical Engineering Report
Apollo Apartments Project
23601 Highway 99
Edmonds, Washington
Dear Mr. Vong,
In accordance with your request and written authorization, Zipper Geo Associates, LLC (ZGA)
has completed the subsurface exploration and geotechnical engineering evaluation for the
proposed Apollo Apartments project at 23601 Highway 99 in Edmonds, Washington. We
previously issued reports for this project dated 12/15/20 and 2/24/22 (Rev 1). This report presents
Revision 2 to our December 15, 2020 report. The purpose of this revision was to address City of
Edmonds review comments. Specifically, this report updates seismic design parameters to 2018
IBC. Our services were completed in general accordance with our Proposal for Geotechnical
Engineering Services (Proposal No. P19322_Rev3) dated June 29, 2020. Written authorization
to proceed was provided by Black -fish Capital, LLC on July 2, 2020. We appreciate the opportunity
to be of service to you on this project. If you have any questions concerning this report, or if we may
be of further service, please contact us.
Sincerely,
Zipper Geo Associates LLC
Robert A. Ross, P.E.
Principal
/2022
19019 3611 Avenue West, Suite E Lynnwood, WA 98036 (425) 582-9928
TABLE OF CONTENTS
INTRODUCTION.............................................................................................................................................1
SITEDESCRIPTION.........................................................................................................................................1
PROJECT UNDERSTANDING..........................................................................................................................1
SUBSURFACE CONDITIONS...........................................................................................................................2
PublishedGeologic Mapping....................................................................................................................
2
SoilConditions..........................................................................................................................................
2
GroundwaterConditions..........................................................................................................................4
Geotechnical Laboratory Testing..............................................................................................................4
CONCLUSIONS AND RECOMMENDATIONS...................................................................................................4
General Considerations.............................................................................................................................4
Geologically Hazardous Areas...................................................................................................................5
SeismicConsiderations.............................................................................................................................7
SitePreparation........................................................................................................................................9
Structural Fill Materials and Placement..................................................................................................10
Utility Trenching and Backfilling.............................................................................................................13
Temporary and Permanent Slopes.........................................................................................................14
TemporaryShoring.................................................................................................................................15
ShallowFoundations...............................................................................................................................17
GradeBeams...........................................................................................................................................18
Permanent Backfilled Retaining Walls....................................................................................................19
Slab -on -Grade Floors..............................................................................................................................20
Drainage Considerations.........................................................................................................................21
Pavements...............................................................................................................................................
21
AsphaltPavements.............................................................................................................................21
ConcretePavements...........................................................................................................................22
Infiltration Considerations......................................................................................................................23
CLOSURE.....................................................................................................................................................23
FIGURES
Figure 1 — Site and Exploration Plan
Figure 2 — Lateral Earth Pressures for Surcharge Loads
APPENDICES
Appendix A — Subsurface Exploration Procedures and Logs
Appendix B — Laboratory Testing Procedures and Results
GEOTECHNICAL ENGINEERING REPORT - REVISION 2
APOLLO APARTMENTS
23601 HIGHWAY 99
EDMONDS, WASHINGTON
Project No. 2361.01
April 22, 2022
INTRODUCTION
This report documents the surface and subsurface conditions encountered at the site and our
geotechnical engineering recommendations for the proposed Apollo Apartments project located
at 23601 Highway 99 in Edmonds, Washington. The project description, site conditions, and our
geotechnical conclusions and design recommendations are presented in the text of this report.
Supporting data including detailed exploration logs, field exploration procedures, results of
laboratory testing, and other supporting information are presented as appendices.
Our geotechnical engineering scope of services for the project included a site reconnaissance,
subsurface evaluation, laboratory testing, geotechnical analysis, and preparation of this report.
The subsurface evaluation completed for this study included 13 exploratory borings (B-1 through
B-13) completed across the site. The explorations extended to depths of about 17'/2 to 40 feet below
existing grades.
SITE DESCRIPTION
The project site is situated at the southeast corner of Highway 99 and 236th Street SW in Edmonds,
Washington. An existing one-story office building with a daylight basement is located in the
northwest corner of the project site and a three-story office building is situated in the central portion
of the site. The remainder of the site is covered with grass and asphalt pavement. The site slopes
down from west to east and varies in elevation from about 448 feet in the southwest corner to 414
feet along the east side of the site, for a total relief of about 34 feet across the site. Site topography
and existing site conditions are presented on the enclosed Site and Exploration Plan, Figure 1.
The site is bordered to the west by Highway 99 and commercial developments beyond, to the east
by an apartment development, to the south by undeveloped land and a restaurant beyond, and to
the north by 236th Street SW and a mobile home park beyond.
PROJECT UNDERSTANDING
It is our understanding that the existing buildings will be demolished, and the project site will be
redeveloped with a new apartment building. We understand that the new building will include two
levels of below -grade parking that daylight to the east and five levels of residential space above.
The parking levels will be accessed from 236th Street SW. Drawings provided to us indicate the
P1 parking level finished floor elevation is about 422 feet. Assuming that excavations for
foundation elements may extend about 2 to 3 feet below finished floor, we anticipate that
maximum temporary construction excavation depths may approach 20 to 21 feet along the
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topographically high western side of the site with decreasing excavation depths to the east. The
excavations will be completed as open cuts in the central portion of the site and shored cuts along
the west side of the site. We anticipate that the building will be supported on conventional shallow
spread foundations and the P1 parking level will utilize concrete pavement.
SUBSURFACE CONDITIONS
Published Geologic Mapping
According to the U.S. Geological Survey Geologic map of the Edmonds East and part of the
Edmonds West quadrangles, Washington (Miscellaneous Field Studies Map MF-1541 by Minard,
J.P., 1983), the site is mapped as being mantled by Quaternary Vashon till deposits (Qvt). The
Vashon till is described as a compact, non -sorted mixture of clay, silt, sand, pebbles, cobbles,
and boulders. Vashon till is often referred to as "hardpan" in its unweathered state due to its very
dense nature caused by compaction resulting from the weight of an overriding glacial mass
thousands of years ago, which was hundreds of meters thick in some areas. The Vashon till has
been glacially over -consolidated and therefore typically has good foundation, floor slab, and
pavement support characteristics in its undisturbed condition. However, the till usually has a very
low permeability.
Soil Conditions
The subsurface evaluation completed for this project included thirteen borings (B-1 to B-13)
located across the site. The borings extended to depths of about 3 to 40 feet below existing grade.
Boring B-8 was terminated at a depth of about 3 feet when a 1-inch diameter PVC pipe was
encountered. Approximate exploration locations are shown on Figure 1 enclosed with this report.
Soils were visually classified in general accordance with the Unified Soil Classification System.
Detailed, descriptive logs of the subsurface explorations and the procedures utilized in the
subsurface exploration program are presented in Appendix A. Stratification boundaries on the
boring logs represent the approximate depth of changes in soil types, although the transition
between materials may have been gradual. The soil types observed in our borings were relatively
consistent but may vary at other locations. The nature and extent of variations may not become
evident until construction. If variations become apparent during construction, it may be necessary
to reevaluate the recommendations of this report.
In general, the explorations encountered asphalt pavement or sod over undocumented fill and
undistubed native soils consisting of weathered glacial till over unweathered glacial till. The following
table presented a summary stratigraphy of the soils encountered in the explorations followed by a
summary description of each soil unit.
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Summary of Subsurface Conditions
Boring
Approx. Ground
Surface
Elevation(ft)
Asphalt
Pavement
Thickness (in)
Approximate Thickness of Soil Unit (ft)
Total Approx.
Depth
Explored (ft)
Topsoil
Fill
Weathered
Glacial Till
Unweathered
Glacial Till
B-1
438
2'/2
N/E
3'/4
3/4
> 13'/z
17'/z
B-2
419
2
N/E
7
2
>9
18
B-3
419
2'/2
N/E
7
2
>12
21
B-4
417
N/E
N/E
4%
2'/2
>13'/2
20'/z
B-5
437
N/E
'/z
2
'/z
>19
22
B-6
446
'/z
N/E
4'/2
2
>29
35'/2
B-7
440
6'/2
N/E
2%
1
>36
40
B-8
429
3
N/E
3
-
-
3
B-9
420
2
N/E
4'/2
1
>15
20'/z
B-10
421
1'/2
N/E
5'/2
'/2
>9'/z
15'/z
B-11
422
N/E
N/E
2'/2
2
>12
16'/2
B-12
424
N/E
'/2
N/E
2%
>153/4
19
B-13
431
5
N/E
3
1
>27
31
1. Ground surface elevations were interpolated from topographic contour lines presented on Figure 1.
2. N/E = Not Encountered
Existing Asphalt Pavement Section: Nine of the borings were completed through asphalt pavement.
The asphalt varied in thickness from approximately'/2 to 6'/2 inches thick and was underlain by little
to no crushed gravel base course.
Topsoil: Organic -rich topsoil was only observed in borings B-5 and B-12 and was estimated to be
approximately 6 inches thick.
Existing Fill: Undocumented fill soils were encountered in all of the borings except boring B-12. The
fill varied in thickness from approximately 2 to 7 feet in thickness. The fill was generally covered with
asphalt or sod and topsoil. It generally consisted of very loose to medium dense sand with varying
proportions of silt and gravel.
Weathered Glacial Till: Soils interpreted as weathered glacial till were encountered in all of the
borings and generally consisted of medium dense sand with variable silt and gravel content.
Unweathered Glacial Till: Soils interpreted as unweathered glacial till were encountered below the
weathered glacial till in all of the borings and extended to the maximum depths explored. In general,
the unweathered glacial till consisted of dense to very dense sand with variable silt and gravel
content.
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Cobbles and boulders were encountered in some of the borings and are not uncommon within
weathered and unweathered glacial till deposits due to the depositional environment of these soils.
Cobbles and boulders should be expected during construction.
Groundwater Conditions
Groundwater and perched groundwater seepage was not observed in the borings at the time of
drilling. However, several soil samples collected within the existing fill soils and weathered glacial
till layer had above -average moisture contents. Borings left open during the day of drilling
collapsed at the approximate depths that were coincident with the elevated moisture contents
indicating that light perched groundwater seepage was present in these zones. Given the dense
to very dense nature and low permeability of the underlying unweathered glacial till soils
encountered, perched groundwater conditions appear to be developed or are developing near the
base of the weathered glacial till and fill layers or in sandy seams within the unweathered glacial
till during periods of extended precipitation. The periodic development of near -surface perched
groundwater conditions is supported by iron oxide staining and soil mottling observed in the
weathered glacial till deposits.
Groundwater conditions should be expected to fluctuate due to variations in the amount of rainfall,
runoff, and other factors not evident at the time the exploration was performed. Therefore,
groundwater levels during construction or at other times in the life of the structure may vary from
those indicated on the logs.
Geotechnical Laboratory Testing
Laboratory testing was completed on select soil samples obtained from the explorations. Moisture
content testing of soil samples obtained within the fill and weathered glacial till ranged from 9.5 to
22.9 percent while the moisture contents within the unweathered glacial till ranged from 5.6 to
15.9 percent. Gradation testing of 17 representative soil samples indicates that the fines content
(the clay and silt fraction) of the soils vary from approximately 7.4 to 36.8 percent.
CONCLUSIONS AND RECOMMENDATIONS
General Considerations
Based on our subsurface exploration program and geotechnical evaluation, we conclude that the
proposed project is feasible from a geotechnical standpoint, contingent on proper design and
construction practices and implementation of the recommendations presented in this report.
Based on our analyses, conventional spread footings and slab -on -grade concrete floors and
pavement can be used for the new building.
Geotechnical engineering recommendations for temporary cuts, temporary shoring, foundations,
floor slabs, and other earthwork related phases of the project are outlined below. The
recommendations contained in this report are based upon the results of field and laboratory
testing (which are presented in Appendices A and 8), engineering analyses, and our current
understanding of the proposed project. ASTM and Washington State Department of
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Transportation (WSDOT) specifications cited herein refer to the current manual published by the
American Society for Testing & Materials and the 2020 edition of the WSDOT Standard
Specifications for Road, Bridge, and Municipal Construction (M41-10).
Geologically Hazardous Areas
The City of Edmonds has established regulations that apply to development of property containing
geologically hazardous areas. Chapter 23.80 of the City of Edmonds Community Development
Code (ECDC) regulates development activities in Geologically Hazard Areas (GHAs). The reader
is referred to the Code for definitions of individual GHAs. The City of Edmonds GIS Portal
indicates that portions of the project site are mapped as Landslide and Erosion Hazard Areas.
Geologically hazardous areas include erosion hazard, landslide hazard, and seismic hazard areas
that are defined as follows:
Erosion Hazard Areas: Erosion hazard areas are at least those areas identified by the U.S.
Department of Agriculture's Natural Resources Conservation Service as having a "moderate to
severe," "severe," or "very severe" rill and inter -rill erosion hazard. Erosion hazard areas are also
those areas impacted by shoreland and/or stream bank erosion. Within the city of Edmonds
erosion hazard areas include:
1. Those areas of the city of Edmonds containing soils that may experience severe to very
severe erosion hazard. This group of soils includes, but is not limited to, the following when
they occur on slopes of 15 percent or greater:
a. Alderwood soils (15 to 25 percent slopes);
b. Alderwood/Everett series (25 to 70 percent slopes);
C. Everett series (15 to 25 percent slopes);
2. Coastal and stream erosion areas which are subject to the impacts from lateral erosion
related to moving water such as stream channel migration and shoreline retreat;
3. Any area with slopes of 15 percent or greater and impermeable soils interbedded with
granular soils and springs or ground water seepage; and
4. Areas with significant visible evidence of ground water seepage, and which also include
existing landslide deposits regardless of slope.
Landslide Hazard Areas: Landslide hazard areas are areas potentially subject to landslides based
on a combination of geologic, topographic, and hydrologic factors. They include areas susceptible
because of any combination of soil, slope (gradient), slope aspect, structure, hydrology, or other
factors. Within the city of Edmonds potential landslide hazard areas include:
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April 22, 2022
1. Areas of ancient or historic failures in Edmonds which include all areas within the earth
subsidence and landslide hazard area as identified in the 1979 report of Robert Lowe
Associates and amended by the 1985 report of GeoEngineers, Inc., and further discussed in
the 2007 report by Landau Associates;
2. Coastal areas mapped as class u (unstable), uos (unstable old slides), and urs (unstable
recent slides) in the Department of Ecology Washington coastal atlas;
3. Areas designated as quaternary slumps, earthflows, mudflows, or landslides on maps
published by the United States Geological Survey or Washington State Department of Natural
Resources;
4. Any slope of 40 percent or steeper that exceeds a vertical height of 10 feet over a 25-foot
horizontal run. Except for rockeries that have been engineered and approved by the engineer
as having been built according to the engineered design, all other modified slopes (including
slopes where there are breaks in slopes) meeting overall average steepness and height
criteria should be considered potential landslide hazard areas);
5. Any slope with all three of the following characteristics:
Slopes steeper than 15 percent;
Hillsides intersecting geologic contacts with a relatively permeable sediment overlying a
relatively impermeable sediment; and
Springs or ground water seepage;
6. Any area potentially unstable as a result of rapid stream incision or stream bank erosion;
7. Any area located on an alluvial fan, presently subject to, or potentially subject to, inundation
by debris flow or deposition of stream -transported sediments; and
8. Any slopes that have been modified by past development activity that still meet the slope
criteria.
Seismic Hazard Areas. Seismic hazard areas are areas subject to severe risk of damage as a
result of earthquake -induced ground shaking, slope failure, settlement, soil liquefaction, lateral
spreading, or surface faulting. These areas are designated as having a "high" and "moderate to
high" risk of liquefaction as mapped on the Liquefaction Susceptibility Map of Snohomish County
by the Washington State Department of Natural Resources or areas located within landslide
hazard areas. [Ord. 4026 § 1 (Att. A), 2016; Ord. 3527 § 2, 2004].
As part of our services, we evaluated the presence of regulated geologically hazardous areas
(GHAs) at the site.
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The NRCS Web Soil Survey maps the site soils as Alderwood-Urban land complex, 2 to 8 percent
slopes. The Alderwood gravelly sandy loam is rated as having a moderate erosion potential on
bare soil where long flow paths can develop, such as roads and trails and slight erosion potential
where 50 to 75 percent of surface soils are disturbed. Although the site is mapped by the NRCS
as having slopes of 2 to 8 percent, and the average slope across the site is less than 15 percent,
the topographic map of the site indicates that portions of the project site meet the ECDC definition
of an Erosion Hazard Area because the slopes exceed 15 percent. Many of these areas will be
eliminated as a result of the proposed development. Provided that the recommendations
presented in this report, as well as the required erosion mitigation measures are implemented, it
is our opinion that the proposed project will not increase the threat of the geological hazards to
adjacent or abutting properties beyond pre -development conditions, will not adversely impact
other critical areas, and the development can be safely accommodated on the site.
The City of Edmonds GIS Portal indicates that portions of the site are mapped as a Landslide
Hazard Area. The site is not mapped as a landslide hazard in the reports referenced above, nor
is it mapped as unstable in the Department of Ecology Coastal Atlas as being unstable. The site
does not appear to meet any on the other criteria presented by the City of Edmonds. Therefore,
it is our opinion the site does not meet the definition of a Landslide Hazard Area. Based on the
very dense soil conditions encountered in our borings and the lack of groundwater, it is our
opinion, pending the development of a grading plan for the project, the site could be developed
as proposed.
Based on the soil and groundwater conditions encountered at the site, it is our opinion that the
potential for liquefaction at the site is very low. The site is also mapped as having very low
liquefaction susceptibility on the Liquefaction Susceptibility Map of Snohomish County'. Based
on the subsurface conditions encountered, the site does not meet the criteria for a Seismic Hazard
Area.
Seismic Considerations
The development was evaluated relative to seismic hazards resulting from ground shaking
associated with the Risk -Targeted Maximum Considered Earthquake (MCER) Ground Motion
Response Acceleration and the Maximum Considered Earthquake Geometric Mean (MCEG) Peak
Ground Acceleration in accordance with the 2018 International Building Code (IBC). The results
of our seismic hazard analyses and recommended seismic design parameters are presented in
the following sections.
Ground Surface Rupture: According to the U.S. Geological Survey Quaternary Fault and Fold
Database of the United States, the closest mapped fault to the project site is the southern Whidbey
Island fault zone. One limb of the fault is approximately 2,575 feet northeast of the project site
and another is approximately 1,350 feet southwest of the site. The most recent deformation of the
southern Whidbey Island fault zone is less than 15,000 years and is in the slip rate category of
1 Washington Division of Geology and Earth Resources, Open File Report 2004-20, Palmer, S.P., Magsino, S.L.,
Bilderback, E.L., Poelstra, J.L., Folger, P.S., and Niggeman, R.A., 2004
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between 0.2 and 1 mm/year. Based on the information described above, we estimate that the
risk associated with fault surface rupture at the site is low.
Landsliding: Based on the relatively gently sloping topography of the site and surrounding vicinity,
as well as the subsurface conditions encountered at the site, the risk of earthquake -induced
landsliding is low.
Soil Liquefaction and Lateral Spread: Liquefaction is a phenomenon wherein saturated
cohesionless soils build up excess pore water pressures during earthquake loading. Liquefaction
typically occurs in loose soils but may occur in denser soils if the ground shaking is sufficiently
strong. The explorations primarily encountered glacially consolidated glacial till. Based on the
dense to very dense nature of these soils and the lack of a groundwater table, it is our opinion
that the potential for liquefaction at the site is low.
Lateral spreading is a phenomenon in which soil deposits which underlie a site can experience
significant lateral displacements associated with the reduction in soil strength caused by soil
liquefaction. This phenomenon tends to occur most commonly at sites where the soil deposits
can flow toward a "free -face", such as a water body. Due to the lack of liquefiable soils at the site
and the lack of a nearby "free -face" condition, it is our opinion that the risk of lateral spreading at
the site is low.
IBC Seismic Design Parameters:
The City of Edmonds has adopted the 2018 edition of the International Building Code. The values
presented in the following table are derived from the 2018 International Building Code and ASCE
7-16.
2015 IBC/ASCE 7-10 Seismic Design Parameters
Parameter
Value
2015 International Building Code Site Classification (IBC)
Site Latitude/Longitude
Mean Magnitude Earthquake
Site Class C
47.7846 /-122.3418
7.01
Site Modified Ground Acceleration, PGAM
0.651g
Spectral Short -Period Acceleration, Ss
1.277g (Site Class B)
Spectral 1-Second Acceleration, S1
0.448g (Site Class B)
Site Coefficient for a Short Period, Fa
1.0
Site Coefficient for a 1-Second Period, Fv
1.307
Spectral Acceleration for a 0.2-Second Period, SMs
1.533g (Site Class C)
Spectral Acceleration for a 1-Second Period, SM1
0.672g (Site Class C)
Design Short -Period Spectral Acceleration, SIDS
1.022g (Site Class C)
Design 1-Second Spectral Acceleration, SD1
0.448g (Site Class C)
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Site Preparation
Apollo Apartments
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Existing Structure Removal: Prior to demolition of the existing buildings, it may be necessary to
complete asbestos and lead -based paint surveys. We recommend the surveys be completed by
an AHERA-certified inspection company. ZGA can provide these services, if requested. All
existing foundation elements should be completely demolished and removed from the proposed
building area.
Existing Utility Removal: We recommend that all underground utilities within the building pad be
completely removed. Utility pipes outside the building envelope could be abandoned in place,
provided they are fully grouted with controlled density fill (CDF) and the trench backfill is density
tested to verify that it meets the compaction levels presented in the project specifications.
Localized excavations made for removal of utilities or existing unsuitable trench backfill should be
backfilled with structural fill as outlined in the following section of this report.
Erosion Control Measures: Stripped surfaces and soil stockpiles are typically a source of runoff
sediments. We recommend that silt fences, berms, straw waddles, and/or swales be installed
around the downslope side of stripped areas and stockpiles in order to capture runoff water and
sediment. If earthwork occurs during wet weather, we recommend that soil stockpiles be protected
with anchored plastic sheeting.
Temporary Drainage: Stripping, excavation, grading, and subgrade preparation should be
performed in a manner and sequence that will provide drainage at all times and provide proper
control of erosion. The site soils that will be exposed during construction have a moderate to high
fines (silt and clay) content (up to about 37 percent) and are therefore highly susceptible to
disturbance and erosion when wet. The site should be graded to prevent water from ponding in
construction areas and/or flowing into and/or over excavations. Exposed grades should be
crowned, sloped, and smooth -drum rolled at the end of each day to facilitate drainage if inclement
weather is forecasted. Accumulated water must be removed from subgrades and work areas
immediately and prior to performing further work in the area. Equipment access may be limited
and the amount of soil rendered unfit for use as structural fill may be greatly increased if drainage
efforts are not accomplished in a timely manner. Successful drainage of saturated zones due to
accumulations of surface water would be relatively slow due to the fines content of the surficial
soils. Instead, aeration or removal and replacement would be more expeditious.
Runoff from the existing paved areas around the site should not be allowed to flow into excavation
areas. We recommend that asphalt berms or sandbags be used to divert runoff around the
excavation areas to a suitable discharge location.
Clearing and Stripping: We anticipate that clearing and stripping of organic -rich soils will be limited
to the grass -covered area on the south side of the site and areas of landscaping. We anticipate
that stripping depths will average about 6 to 8 inches. Areas of deeper organics should be
expected around the root balls of the plants.
Subgrade Preparation: Once site preparation is complete, all areas that do not require over -
excavation and are at design subgrade elevation or areas that will receive new structural fill should
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be compacted to a firm and unyielding condition. Depending on the time of year that earthwork
takes place, some moisture conditioning of site soils may be required to achieve a moisture
content appropriate for compaction. This is generally within ±2 percent of the soil's optimum
moisture content.
We recommend that earthwork be completed during drier periods of the year, if feasible, when
soil moisture content can be controlled by aeration and drying. If earthwork or construction
activities take place during extended periods of wet weather, or if the in -situ moisture conditions
are elevated above the optimum moisture content, the soils could become unstable or not be
compactable. In the event the exposed subgrade becomes unstable, yielding, or unable to be
compacted due to high moisture conditions, we recommend that the materials be removed to a
sufficient depth in order to develop stable subgrade soils that can be compacted to the minimum
recommended levels. The severity of construction problems will be dependent, in part, on the
precautions that are taken by the contractor to protect the subgrade soils.
Once compacted, subgrades should be evaluated by a geotechnical engineer through visual
observation, density testing, and proof rolling if the building excavation is accessible with heavy
rubber -tired construction equipment to assess the subgrade adequacy and to detect soft and/or
yielding soils. In the event that compaction fails to meet the specified criteria, the upper 12 inches
of subgrade should be scarified and moisture conditioned as necessary to obtain at least 95
percent of the maximum laboratory density (per ASTM D1557).
To protect stable subgrades, either inside or outside the building excavation, we recommend
using crushed rock or crushed recycled concrete. The thickness of the protective layer should be
determined at the time of construction and be based on the moisture condition of the soil and the
amount of anticipated construction traffic.
Freezing Conditions: If earthwork takes place during freezing conditions, all exposed subgrades
should be allowed to thaw and then be compacted prior to placing subsequent lifts of structural
fill. Alternatively, the frozen material could be stripped from the subgrade to expose unfrozen soil
prior to placing subsequent lifts of fill or foundation components. The frozen soil should not be
reused as structural fill until it is allowed to thaw and adjusted to the proper moisture content,
which may not be possible during winter months.
Structural Fill Materials and Placement
All fill placed within the building area, as well as beneath paved surfaces, sidewalks, and other
settlement -sensitive structures, should be placed as structural fill. The structural fill should be
placed after removal of any existing disturbed soils and after the surface has been prepared and
compacted as recommended above. Subgrades should be evaluated by testing for the minimum
compaction standard, and/or by proof -rolling in the presence of the geotechnical engineer, prior
to filling.
Laboratory Testing: Representative samples of on -site and imported soils to be used as structural
fill should be submitted for laboratory testing at least 4 days in advance of its intended use in
order to complete the necessary Proctor tests.
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GeoprofessionalConsultants April 22, 2022
Re -Use of Site Soils as Structural Fill: The suitability of excavated site soils for compacted
structural fill will depend on the gradation and moisture content of the soil when it is placed. As
the amount of fines (that portion passing the U.S. No. 200 sieve) increases, the soil becomes
increasingly sensitive to small changes in moisture content and adequate compaction becomes
more difficult or impossible to achieve. Soils containing more than about 5 percent fines cannot
be consistently compacted to a dense, non -yielding condition when the water content is greater
than optimum. Optimum moisture content is that moisture which results in the greatest
compacted dry density with a specified compactive effort.
It is our opinion that the weathered and unweathered glacial till soils encountered at the site are
suitable for reuse as general structural fill from a compositional standpoint provided it can be
placed and compacted in accordance with the recommendations presented in this report. Our
subsurface exploration was completed during the dry season and much of the soil encountered
during our evaluation appeared to be slightly above its estimated optimum moisture content. We
anticipate that some of these soils may be above their optimum moisture content during
construction and require drying to achieve adequate compaction. The reuse of site soils as
structural fill during wet weather will be much more difficult. We recommend that site soils used
as structural fill have less than 4 percent organics by weight and have no woody debris greater
than '/z inch in diameter. We recommend that all organic -rich soil derived from earthwork activities
be utilized in landscape areas or wasted from the site.
Some of the fill soils encountered across the site may also be suitable for reuse as structural fill,
although we expect the composition and quality of the fill to vary across the site. This material
should be considered as common borrow that is susceptible to disturbance when wet.
Imported Structural Fill: During wet weather, under wet site conditions, or if the soils cannot be
properly dried, the use of on -site soils for structural fill may not be acceptable, requiring suitable
materials to be imported. Imported fill should consist of well -graded sand or sand and gravel.
Under wet conditions, the fines content should be limited to less than 5 percent (based by weight
on the minus No. 4 sieve fraction using the wet sieve analysis). Typically, soils containing less
than 5 percent fines can be compacted under a wider variety of weather conditions.
During extended periods of dry weather, we recommend imported fill meet the requirements of
Common Borrow, Options 1 or 2, as specified in Section 9-03.14(3) of the WSDOT Standard
Specifications. During wet weather, higher -quality structural fill might be required, as Common
Borrow may contain sufficient fines to be moisture sensitive. In this case, we recommend that
imported structural fill meet the requirements of Gravel Borrow as specified in Section 9-03.14(1)
of the WSDOT Standard Specifications.
Retaining Wall Backfill: With the exception of permanent foundation walls constructed directly in
front of soldier pile retaining walls, any site retaining walls should include a drainage fill zone
extending at least 18 inches back from the back face of wall for the entire wall height. The drainage
fill should meet the requirements of Gravel Backfill for Walls as specified in Section 9-03.12(2) of
the WSDOT Standard Specifications.
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GeoprofessionalConsultants April 22, 2022
Pavement Subgrades: Any structural fill used within the upper 2 feet below pavement sections
should have a minimum California Bearing Ratio (CBR) of 15 when compacted to a minimum of
95 percent of the modified Proctor maximum dry density. A CBR value of 15 is representative of
the existing soils encountered when compacted as recommended in this report.
Moisture Content: The suitability of soil for use as structural fill will depend on the time of year,
the moisture content of the soil, and the fines content (that portion passing the U.S. No. 200 sieve)
of the soil. As the amount of fines increases, the soil becomes increasingly sensitive to small
changes in moisture content. Soils containing more than about 5 percent fines (such as most of
the on -site soils) cannot be consistently compacted to the appropriate levels when the moisture
content is more than approximately 2 percent above or below the optimum moisture content (per
ASTM D1557). Optimum moisture content is that moisture content which results in the greatest
compacted dry density with a specified compactive effort.
Fill Placement: Structural fill should be placed in horizontal lifts not exceeding 10 inches in loose
thickness. Each lift of fill should be compacted using compaction equipment suitable for the soil
type and lift thickness. Each lift of fill should be compacted to the minimum levels recommended
below based on the maximum laboratory dry density as determined by the ASTM D1557 Modified
Proctor Compaction Test. Moisture content of fill at the time of placement should be within plus
or minus 2 percent of optimum moisture content for compaction as determined by the ASTM
D1557 test method. The actual lift thickness will be a function of the type, size, and weight of the
compaction equipment.
Compaction Criteria: Our recommendations for soil compaction are summarized in the following
table. Structural fill for roadways and utility trenches in municipal rights -of -way should be placed
and compacted in accordance with City of Seattle codes and standards. We recommend that a
geotechnical engineer be present during grading so that an adequate number of density tests
may be conducted as structural fill placement occurs. In this way, the adequacy of the earthwork
may be evaluated as it proceeds.
RECOMMENDED SOIL COMPACTION LEVELS
Location
Minimum Percent Compaction*
All fill below building floor slabs and foundations
95
Upper 2 feet of fill below pavements
95
Pavement fill below two feet
92
Retaining wall backfill less than 2 feet from wall
90 - 92
Retaining wall backfill more than 2 feet from wall
95
Upper two feet of utility trench backfill
95
Utility trenches below two feet
92
Landscape Areas
90
* ASTM D 1557 Modified Proctor Maximum Dry Density
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ZipperGeo
Geoprofessional Consultants
Utility Trenching and Backfilling
Apollo Apartments
Project No. 2361.01
April 22, 2022
We recommend that utility trenching conform to all applicable federal, state, and local regulations,
such as OSHA and WISHA, for open excavations. Trench excavation safety guidelines are
presented in WAC Chapter 296-155 and WISHA RCW Chapter 49.17.
Dewatering: Perched groundwater was not observed in our borings at the time of drilling.
However, zones of wet soils were encountered that would likely have seeped over a longer period
of time that that at the time of drilling. Soil mottling and iron oxide staining suggest the
development of periodic perched groundwater within the weathered glacial till deposits. Some
excavations for utilities and underground structures may encounter zones of perched groundwater
that may develop above the dense unweathered glacial till or in sandy seams within the
unweathered fill. The amount of perched groundwater seepage that may be encountered in site
excavations will likely be a function of the time of year, the size of the excavation, the excavation
depth, and how long the excavation remains open. The type and extent of dewatering measures
needed, if any, will be a function of the groundwater conditions at the time of construction.
Temporary systems could include pumped sumps, wellpoints or pumped wells.
If seepage is encountered, flattening excavation sidewalls may be necessary to reduce the risk
of caving. Otherwise, some caving of utility trench sidewalls should be anticipated where
groundwater seepage is encountered. If dewatering becomes necessary, the appropriate type of
dewatering system and means of disposing the water should be determined by the contractor
based on the conditions encountered.
Utility Subgrade Preparation: We recommend that all utility subgrades be firm and unyielding and
free of all soils that are loose, disturbed, or pumping. Such soils should be removed and replaced,
if necessary. All structural fill used to replace over -excavated soils should be compacted as
recommended in the Structural Fill section of this report. If soft utility foundation soils are
encountered, we recommend that they be over -excavated and replaced with crushed rock.
Structures such as manholes and catch basins which extend into soft soils should be underlain
by at least 4 inches of crushed gravel fill compacted to a firm and unyielding condition.
Bedding: We recommend that bedding material be placed above and below all utilities in general
accordance with the City of Edmonds Standard Plans and Specifications. If water is encountered
in the excavations, it should be removed prior to fill placement. We recommend that a minimum
of 4 inches of bedding material be placed above and below all utilities or in general accordance
with the utility manufacturer's recommendations and local ordinances. We recommend that pipe
bedding consist of Gravel Backfill for Pipe Zone Bedding as specified in Section 9-03.12(3) of the
WSDOT Standard Specifications. All trenches should be wide enough to allow for compaction
around the haunches of the pipe, or material such as pea gravel should be used below the spring
line of the pipes to eliminate the need for mechanical compaction in this portion of the trenches.
If water is encountered in the excavations, it should be removed prior to fill placement.
Trench Backfill: Materials, placement and compaction of utility trench backfill should be in
accordance with the recommendations presented in the Structural Fill section of this report. In
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Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
our opinion, the initial lift thickness should not exceed one foot unless recommended by the
manufacturer to protect utilities from damage by compacting equipment. Light, hand operated
compaction equipment may be utilized directly above utilities if damage resulting from heavier
compaction equipment is of concern.
Some on -site soils may be suitable for use as trench backfill from a compositional standpoint,
provided the moisture content allows for compaction to the minimum recommended levels. If
borrow material is required, it should be selected based on the weather at the time of use. The
use of gravel borrow, as described in the Structural Fill section of this report, would be suitable
for trench backfill under most weather conditions.
Temporary and Permanent Slopes
We anticipate that temporary open cuts may be utilized in conjunction with shoring during the
construction of foundation elements for the proposed structure. Temporary excavation slope
stability is a function of many factors, including:
• The presence and abundance of groundwater;
• The type and density of the various soil strata;
• The depth of cut;
• Surcharge loadings adjacent to the excavation; and
• The length of time the excavation remains open.
As the cut is deepened, or as the length of time an excavation is open increases, the likelihood of
sidewall sloughing or failure increases; therefore, maintenance of safe slopes and worker safety
should remain the responsibility of the contractor, who is present at the site, able to observe
changes in the soil conditions, and monitor the performance of the excavation.
It is exceedingly difficult under the variable circumstances to pre -establish a safe and
"maintenance -free" temporary cut slope angle. Therefore, it should be the responsibility of the
contractor to maintain safe temporary slope configurations since the contractor is continuously at
the job site, able to observe the nature and condition of the cut slopes, and able to monitor the
subsurface materials and groundwater conditions encountered. Unsupported vertical slopes or
cuts deeper than 4 feet are not recommended if worker access is necessary. The cuts should be
adequately sloped, shored, or supported to prevent injury to personnel from local sloughing and
spalling. Temporary slope angles should conform to applicable Federal, State, and Local
regulations based on the subsurface conditions observed at the time of construction.
Based on the conditions observed in the borings, the fill and weathered glacial till soils
encountered in the upper 7 feet of the explorations appear to be representative of Type B soils,
as described in Chapter 296-155, Part N, Excavation Trenching and Shoring, of the Washington
Administrative Code (WAC). According to the Code, excavations less than 20 feet deep in Type
B soils may be cut at a maximum temporary slope angle of 45 degrees (1 H:1 V). The underlying
unweathered glacial till soils encountered in the explorations appear to be representative of Type
A soils, as described in Chapter 296-155, Part N, Excavation Trenching and Shoring, of the
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Zi pperGeo Apollo Apartments
Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
Washington Administrative Code (WAC). According to the Code, excavations less than 20 feet
deep in Type A soils may be cut at a maximum temporary slope angle of 53 degrees (3/41-1:1V).
Therefore, for preliminary planning purposes we recommend maximum temporary slope angles
of 45 degrees (11-1:1V) and 53 degrees (3/41-1:1V) for weathered glacial till and fill spoils and
unweathered glacial till, respectively. According to Chapter 296-155 of the WAC, the contractor
should make a determination of excavation side slopes based on classification of soils and site
conditions encountered at the time of excavation. Temporary cuts may need to be constructed at
flatter angles based upon the soil moisture and groundwater conditions (including perched
groundwater) at the time of construction and the location of soil stockpiles construction equipment,
or other surcharge loads. Adjustments to the slope angles should be determined by the contractor
at that time.
We recommend that all permanent cut or fill slopes constructed in native soils be designed at a
2H:1 V (Horizontal:Vertical) inclination or flatter. All permanent cut and fill slopes should be
adequately protected from erosion both temporarily and permanently.
Temporary Shoring
We understand that temporary shoring will be used to support the cut required to construct the
lower parking level. Temporary shoring consisting of soil nail will be utilized to support the western
side of the excavation. This section presents our recommendations for temporary shoring.
Soil Nail Shoring Design Parameters: Based on soil conditions encountered in borings B-1 and
B-7, we expect soil conditions encountered in soil nail excavations will generally consist of about
5 feet of loose sand fill/weathered glacial till underlain by medium dense to very dense glacial till
soils. The following presents our recommended soil design parameters that should be utilized for
soil nail shoring design and analysis.
• Fill/Weathered Till: y = 125 pcf, cp = 30°, c = 0 psf, Qd = NA
• Glacial Till: y = 135 pcf, cp = 40°, c = 200 psf, Qd = 3.4 k/ft
• where:
o y = moist unit weight in pounds per cubic foot,
o cp = effective friction angle in degrees,
o c = effective cohesion in pounds per square foot, and
o Qd = allowable nail pullout resistance in kips per foot.
■ Note Qd assumes a minimum 6 inch diameter drill hole.
The above -recommended values for friction angle and cohesion are based on typical values for
Glacial Till deposits published in the Washington State Department of Transportation's
Geotechnical Design Manual. The actual pullout strength values will depend on the materials and
installation methods and should be confirmed by testing. Installation methods should be the
responsibility of the contractor.
Soil Nail Construction: We recommend that soil nail grout be pumped into the soil nail holes by
tremie methods in order to force grout up from the bottom of the hole and to provide a continuously
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GeoprofessionalConsultants April 22, 2022
grouted soil nail. We recommend that a minimum of two sacrificial, 200 percent verification tests
be performed in order to evaluate the ultimate pullout resistance and the load deformation
performance of the soil nail. Verification testing should be accomplished prior to installation of
production nails. The location of the verification tests should be selected by the contractor and
approved by Zipper Geo. The drilling method, hole diameter, and depth of soil nail should be
identical to the production soil nails. Additionally, 5 percent of production soil nails should be proof
tested to 150 percent of design load to confirm the design capacity and appropriate construction
methods.
Temporary Shoring Deformation Monitoring: Any time an excavation is made below the level of
existing buildings, utilities, or other structures, there is risk of damage even if a well -designed
shoring system has been planned. Therefore, we recommend that the shoring system and
surrounding areas be monitored for deformation. Deformation monitoring should be completed
through optical survey of points established as follows:
• At the top of wall on 20 feet centers, and
• between Wall Sta. 1+89 to 2+82 along the back of the Hwy. 99 sidewalk at 25 foot
centers.
Optical survey should have an accuracy of ± 0.01feet and should be completed by a licensed
surveyor.
Survey of the monitoring points should be performed a minimum of twice per week, with at least
one of the readings completed during shoring installation and excavation. Survey frequency can
be decreased after the shoring system has been installed and excavation is complete if the data
indicates little or no additional movement. Surveying must continue until the permanent structure
(including floor slabs as braces) is complete up to final and street grades. The survey frequency
will be determined by Zipper Geo after review and approval by the City of Edmonds.
Monitoring results should be provided weekly to Zipper Geo. Zipper Geo will review the survey
data and provide an evaluation of wall performance along with graphical representation of wall
movement versus time and survey data to the City of Edmonds on at least a weekly basis. Zipper
Geo and the City of Edmonds should be immediately notified if any unusual or significantly
increase movement occurs.
If 0.5 inches or more movement occurs between two consecutive readings or if total movements
reach 0.5 inches, Zipper Geo and the City of Edmonds should be notified immediately. At that
level of movement, the contractor should determine the cause of displacement and develop
remedial measures sufficient to limit total wall movements to 1 inch. All earthwork and
construction activities must be directed towards immediate implementation of remedial measures
necessary to limit total wall movements to 1 inch.
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ZipperGeo
Geoprofessional Consultants
Shallow Foundations
Apollo Apartments
Project No. 2361.01
April 22, 2022
Conventional shallow spread and continuous footings are suitable for support of the proposed
structure, provided the bearing soils are prepared in accordance with the recommendations
presented herein. Based on the subsurface conditions encountered, we anticipate that the
western portion of the garage structure, and some of the western residential wing, will be
supported on dense to very dense unweathered glacial till. However, the eastern portion of the
garage structure is situated over an area where loose to medium dense undocumented fill has
been placed. When undocumented fill is present, there is risk of supporting footings, floor slabs,
and pavements on or above the existing fill. The fill does not appear to be consistently or
adequately compacted based on the blowcount data and may contain compressible or unsuitable
materials that can cause excessive settlements. Therefore, we do not recommend supporting
foundations on existing fill soils. Remedial improvement such as over -excavation and placing it
back with more compactive effort is recommended. Other areas of loose soil may be revealed
during earthwork and may need similar remedial measures. Even with the typical construction
testing services, there is an inherent risk for the owner that compressible fill or unsuitable material
within or buried by the fill will not be discovered. This risk of unforeseen conditions cannot be
completely eliminated without removing the existing fill and replacing it with compacted structural
fill.
Bearing Subgrade: We recommend that building foundations be supported on a properly prepared
native subgrade or on structural fill placed above suitable native soils. Foundations should not
be supported on existing undocumented fill. We recommend that undocumented fill soils be over -
excavated to a depth where the underlying medium dense to very dense glacial deposits are
encountered and be replaced with compacted structural fill or controlled density fill (CDF) that has
a minimum 28-day compressive strength of 150 psi. The foundation subgrade should be
observed by a representative of ZGA prior to placement of any structural fill, formwork or
reinforcing steel. The excavation to remove existing fill should extend laterally away from each
side of the footing 8 inches for each foot the excavation extends vertically below the foundation if
compacted structural fill is used. Alternatively, if CDF is used, the excavation should extend
laterally away from each side of the footing a distance of 6 inches, regardless of the depth of over -
excavation. The depth to suitable bearing soils is presented in the following table.
Estimated Depth to Suitable Bearing Soils
Boring No.
Depth to 3,000 psf Bearing Soils
(ft)
Depth to 6,000 psf Bearing Soils
(ft)
B-1
4
5
B-2
61/2
7
B-3
7
9
B-4
4'/2
61/2
B-5
21/2
3
B-6
41/2
6'/2
B-7
4
41/2
B-8
B-9
41/2
5
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Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
B-10
6
61/2
B-11
2'/2
4 t/2
B-12
1 t/2
4
B-13
31/2
8
Boring terminated at shallow depth due to utility
Allowable Bearing Pressure: Continuous and isolated column footings bearing on subgrades
prepared as recommended above may be designed for a maximum allowable, net, bearing
pressure of 3,000 psf if supported on medium dense native weathered glacial till soils or
compacted structural fill, and 6,000 psf if supported on dense to very dense native glacial soils or
CDF placed on dense to very dense native glacial soils. A one-third increase of the bearing
pressure may be used for short -tern dynamic loads such as wind and seismic forces. The above -
recommended allowable bearing pressures include a 3.0 factor of safety.
Shallow Foundation Depth and Width: For frost protection, the bottom of all exterior footings
should bear at least 18 inches below the lowest adjacent outside grade, whereas the bottoms of
interior footings should bear at least 12 inches below the surrounding slab surface level. We
recommend that all continuous wall and isolated column footings be at least 12 and 24 inches
wide, respectively.
Lateral Resistance: We recommend using an ultimate base friction and passive earth values of
0.55 for footings supported on undisturbed native soils, CDF, and structural fill compacted to a
minimum of 95 percent of the modified Proctor maximum dry density. We recommend using an
ultimate passive resistance of 650 and 475 pcf equivalent fluid pressure, respectively, for footings
cast directly against dense to very dense native soils and footings with compacted structural fill
placed around them. An appropriate safety factor (or load/resistance factors) should be included
for calculating resistance to lateral loads. For allowable stress design, we recommend a minimum
1.5 safety factor. We recommend that passive resistance be neglected in the upper 18 inches of
embedment.
Estimated Settlement: Assuming the foundation subgrade soils are prepared in accordance with
recommendations presented herein, we estimate that total and differential settlements will be less
than one inch and t/2 inch, respectively, over a distance of 40 feet.
Grade Beams
Because the west residential wing diverges off of the below -grade parking structure, the wing will
transition off the garage structure and on to wall backfill and then on to native glacial till soils. The
transition fill should be expected to settle a small amount even when compacted to 92 to 95
percent of its modified Proctor maximum dry density. Over time, we estimate that the backfill could
settle one inch or more. In order to not rely on the backfill soils for foundation support, we
understand that grade beams will be used to span over the wall backfill. Based on an assumed
temporary cut on the order of 1 H:1 V, it appears that the grade beams would need to span about
25 feet perpendicular to the parking garage wall. Where grade beams are not perpendicular to
the garage wall, the grade beams will be longer. We recommend using a subgrade modulus of
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Zi pperGeo Apollo Apartments
Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
100 pci and 500 pci for structural fill compacted to a minimum of 95 percent of the modified Proctor
maximum dry density and undisturbed dense to very dense glacial till, respectively.
Permanent Backfilled Retaining Walls
We expect the project to include backfilled cast -in -place concrete retaining walls. For
recommended bearing capacities and lateral resistance parameters, refer to the Shallow
Foundations section above. Additional recommendations for these structures are provided below.
Lateral Earth Pressures: The lateral soil pressures acting on backfilled retaining walls will depend
on the nature and density of the soil behind the wall, and the ability of the wall to yield in response
to the earth loads. Yielding walls (i.e. walls that are free to translate or rotate) that are able to
displace laterally at least 0.001 H, where H is the height of the wall, may be designed for active
earth pressures. Non -yielding walls (i.e. walls that are not free to translate or rotate) should be
designed for at -rest earth pressures. Non -yielding walls include walls that are braced to another
wall or structure, and wall corners.
The recommended lateral earth pressures are based on the assumption that no buildup of
hydrostatic pressure behind the wall develop. If groundwater is allowed to saturate the backfill
soils, hydrostatic pressures will act against the wall. Assuming that walls are backfilled and
drained as described in the following paragraphs, we recommend that yielding and non -yielding
walls supporting horizontal backfill be designed using the following equivalent fluid densities.
Recommended Lateral Earth Pressures
Fill Compaction Level
Active Earth Pressure
At -Rest Earth Pressure
Min. 95%
40
60
Design of permanent retaining walls should consider additional earth pressure resulting from the
design seismic event. For the seismic case, walls should be designed for an additional uniform,
total seismic earth pressure distribution of 11 H.
The above -recommended lateral earth pressures do not include the effects of sloping backfill
surfaces, surcharges such as traffic loads, other surface loading, or hydrostatic pressures. For
traffic surcharges located within a 1 H:1 V envelope extending up from finished grade at the face
of the wall, we recommend an equivalent soil surcharge of 2 feet (250 psf) be added. Other
surcharges from construction equipment and construction materials should be assessed using
the surcharge diagrams presented on Figure 2 of this report.
All backfilled walls should include a drainage aggregate zone extending a minimum of two feet
from the back of wall for the full height of the wall and wide enough at the base of the wall to allow
seepage to flow to the footing drain. We recommend that the drainage aggregate consist of
material meeting the requirements of WSDOT 9-03.12(2), Gravel Backfill for Walls. A minimum
4-inch diameter, perforated PVC drainpipe should be provided at the base of backfilled walls to
collect and direct subsurface water to an appropriate discharge point. We recommend that the
drainpipe be enveloped in free -draining aggregate meeting WSDOT 9-03.12(4), Gravel Backfill
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Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
for Drains. We recommend wrapping the footing drain aggregate with a non -woven geotextile,
such as Mirafi 140N, or equivalent. If wall backfill outside the drainage zone has more than 10
percent fines, we recommend that a non -woven filter fabric such as Mirafi 160N or equivalent be
placed between the drainage aggregate and structural backfill to limit the amount of fines
migration into the drainage aggregate.
Slab -on -Grade Floors
We anticipate the parking level P1 may include conventional concrete slab -on -grade floors for
non -vehicle areas such as mechanical and/or storage rooms as well as concrete pavements
intended to support passenger vehicle traffic. Recommendations for building slab -on -grade
concrete floors and parking garage concrete pavements are presented below.
Subgrade Conditions and Preparation: The native glacial till soils appear to be suitable for support
of the slabs provided they can be compacted to the minimum recommended levels. Where
unsuitable soil is present, such as loose soils or undocumented fill, we recommend that the
material be over -excavated and replaced with common borrow or select borrow, depending on
the prevailing weather conditions. Subgrades should be prepared in accordance with the
recommendations presented in the Subgrade Preparation section of this report.
Floor Slab Base: To provide a capillary break and uniform slab bearing surface, we recommend
the on -grade slabs in non -parking areas be underlain by a 4-inch thick layer of compacted clean
crushed rock. We recommend that the drainage aggregate conform to the graduation
requirements for Crushed Surfacing Base Course with an adjusted maximum percent passing the
U.S. No. 200 sieve of 3 percent or a free -draining sand and gravel with less than 3 percent passing
the No. 200 sieve.
Vapor Retarder: From a geotechnical standpoint, a vapor barrier is not considered to be
necessary for the proposed building. Where potential slab moisture is a concern or where
moisture sensitive floor coverings are planned, we recommend that a 10- to 15-mil moisture
barrier be installed beneath all interior slabs. We recommend using a puncture -resistant product
such as Stego Wrap or an approved equivalent that is classified as a Class A vapor retarder in
accordance with ASTM E1745. Puncturing the vapor barrier should be avoided; construction
traffic should not be allowed to drive over any vapor barrier material. The slab designer should
and contractor should refer to ACI 302 for procedures and cautions regarding the use and
placement of a vapor retarder. We recommend that installation of the vapor barrier be completed
in accordance with the manufacturers recommendations.
Subgrade Modulus: For design of on -grade concrete slabs supported on dense to very dense
native soils, we recommend a vertical modulus of subgrade reaction of 300 pounds per cubic inch
(pci) be used. Where structural fill will support the concrete slabs, we recommend using a
modulus of 200 pci.
Parking Garage Concrete Pavement: To provide a uniform slab bearing surface, capillary break,
and even working surface, we recommend the on -grade slabs be underlain by a 6-inch thick layer
of compacted crushed rock meeting the requirements of Crushed Surfacing Base Course as
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Zi pperGeo Apollo Apartments
Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
specified in Section 9-03.9(3) of the WSDOT Standard Specifications with the modification that a
maximum of 5 percent of the material passes the U.S. No 200 sieve. Alternatively, we recommend
using Type 22, 1/4-inch Crushed Gravel, per City of Seattle Standard Specification 9-03.14, Mineral
Aggregate Chart.
Parking level concrete pavement design recommendations are based on an assumed modulus
of rupture of 600 psi and a minimum compressive strength of 4,000 psi for the concrete. We
recommend that concrete pavements be lightly reinforced to control cracking and have relatively
closely spaced control joints on the order of 10 to 12 feet. We recommend that minimum
reinforcement consist of 6x6-W2.OxW2.0 welded wire fabric, or equivalent.
Drainage Considerations
Surface Drainage: Final site grades should be sloped to carry surface water away from buildings
and other drainage -sensitive areas. Additionally, site grades should be designed such that
concentrated runoff on softscape surfaces is avoided.
Subsurface Perimeter Drainage: We recommend a permanent subsurface drainage system be
installed around the perimeter of the structure. A minimum 4-inch diameter, perforated PVC
drainpipe should be provided at the base of backfilled walls to collect and direct subsurface water
to an appropriate discharge point. We recommend that the drainpipe be enveloped in free -
draining aggregate meeting WSDOT 9-03.12(4), Gravel Backfill for Drains. We recommend
wrapping the footing drain aggregate with a non -woven geotextile, such as Mirafi 140N, or
equivalent. We recommend that a minimum of 2 feet of free -draining aggregate be placed against
stem walls and that it consist of material meeting the requirements of WSDOT 9-03.12(2), Gravel
Backfill for Walls.
Pavements
Asphalt Pavements
Pavement Life and Maintenance: It should be realized that asphaltic pavements are not
maintenance -free. The following pavement sections represent our minimum recommendations
for an average level of performance during a 20-year design life; therefore, an average level of
maintenance will likely be required. A 20-year pavement life typically assumes that an overlay will
be placed after about 12 years. Thicker asphalt, base, and subbase courses would offer better
ling -term performance, but would cost more initially. Conversely, thinner courses would be more
susceptible to "alligator" cracking and other failure modes. As such, pavement design can be
considered a compromise between a high initial cost and low maintenance costs versus a low
initial cost and higher maintenance costs.
Soil Design Values: The existing subgrade soils are anticipated to consist of a varying mixture of
silt, sand and gravel. Based on the typical values provided by similar material, we have estimated
a California Bearing Ratio (CBR) value of 15 percent for this project.
Page 21
Zi pperGeo Apollo Apartments
Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
Traffic Design Values: No traffic loading was provided for this project. We have assumed
relatively low traffic volumes for light- and heavy-duty pavements. If traffic routes are expected
across the site that could increase the estimated traffic loading, ZGA should be notified so that
we can re -analyze the pavement sections.
Recommended Pavement Sections: For light -duty pavements (parking lot areas), we recommend
21/2 inches of asphalt concrete over 4 inches of crushed rock base course. For heavy-duty
pavements (main access roads, truck delivery routes, etc.), we recommend 3 inches of asphalt
concrete over 6 inches of crushed rock base course.
Materials and Construction: We recommend the following regarding asphalt pavement materials
and pavement construction.
• Subgrade Preparation: In areas that are at grade, the upper 12 inches of pavement
subgrade should be compacted to a minimum of 95 percent of the modified Proctor
maximum dry density. Subsequently, the subgrades should be proof -rolled with a loaded
dump truck or other suitable heavy equipment to determine that the subgrade is firm and
unyielding. Areas that are soft or yielding should be repaired as necessary to meet the
compaction and proof -rolling recommendations presented herein.
• Asphalt Concrete: We recommend that the asphalt concrete conform to Section 9-02.1(4)
for PG 58-22 or PG 64-22 Performance Graded Asphalt Binder as presented in the 2020
WSDOT Standard Specifications. We also recommend that the gradation of the asphalt
aggregate conform to the aggregate gradation control points for 1/2-inch mixes as
presented in Section 9-03.8(6), HMA Proportions of Materials.
• Base Course: We recommend that the crushed aggregate base course conform to
Section 9-03.9(3), Crushed Surfacing Base Course, of the WSDOT Standard
Specifications.
• Asphalt and Base Compaction: All base material should be compacted to at least 95
percent of the maximum dry density determined in accordance with ASTM D1557 or to a
firm and unyielding condition based upon proof rolling. We recommend that asphalt be
compacted to a minimum of 92 percent and a maximum of 97 percent of the theoretical
maximum density.
Concrete Pavements
The following concrete pavement recommendations are intended for exterior concrete slabs
subject to traffic loading. Please refer to the Parking Garage Concrete Pavement section on page
18 for on -grade parking garage recommendations.
Concrete Properties and Thickness: Concrete pavement design recommendations are based on
an assumed modulus of rupture of 600 psi and a minimum compressive strength of 4,000 psi for
the concrete. For light duty pavements, we recommend 5 inches of concrete over 4 inches of
Page 22
Zi pperGeo Apollo Apartments
Project No. 2361.01
GeoprofessionalConsultants April 22, 2022
crushed aggregate base. For heavy duty pavements, we recommend 6 inches of concrete over
4 inches of crushed aggregate base.
Concrete Pavement Joints and Reinforcing: We recommend that concrete pavements be
reinforced and have relatively closely spaced control joints on the order of 10 to 12 feet. We
recommend that minimum reinforcement consist of 6x6-W2.OxW2.0 welded wire fabric or
equivalent. We also recommend that loading dock and trash enclosure pavements be reinforced
with #4 bars at 15 inches each direction.
Infiltration Considerations
Our explorations encountered undocumented fill soils of varying relative compaction over
hydraulically restrictive glacial till deposits that can lead to seasonal perched groundwater
development. Additionally, there is limited space for placement of an infiltration system outside
of the building footprint while maintaining minimum separations distances form the building and
surrounding properties. Infiltrating into loose fill soils could cause them to settle. Based on the
conditions encountered, it is our opinion that the site is not suitable for infiltration.
CLOSURE
The analysis and recommendations presented in this report are based, in part, on the explorations
completed for this study. The number, location, and depth of the explorations were completed
within the constraints of budget and site access so as to yield the information to formulate our
recommendations. Project plans were in the preliminary stage at the time this report was
prepared. We therefore recommend we be provided an opportunity to review the final plans and
specifications when they become available in order to assess that the recommendations and
design considerations presented in this report have been properly interpreted and implemented
into the project design.
The performance of earthwork, structural fill, shoring, foundations, and pavements depend greatly
on proper site preparation and construction procedures. We recommend that Zipper Geo
Associates, LLC be retained to provide geotechnical engineering services during the earthwork -
related construction phases of the project. If variations in subsurface conditions are observed at
that time, a qualified geotechnical engineer could provide additional geotechnical
recommendations to the contractor and design team in a timely manner as the project
construction progresses.
This report has been prepared for the exclusive use of Blackfish Capital LLC, and their agents,
for specific application to this project and has been prepared in accordance with generally
accepted geotechnical engineering practices. No warranties, express or implied, are intended or
made. Site safety, excavation support, and dewatering requirements are the responsibility of
others. In the event that changes in the nature, design, or location of the project as outlined in
this report are planned, the conclusions and recommendations contained in this report shall not
be considered valid unless Zipper Geo Associates, LLC reviews the changes and either verifies
or modifies the conclusions of this report in writing.
Page 23
----------- fL--------
-------
FOUND REBAR AND CAP
/ STAMPED iVEBB 162J0"
0.1'(W) OF CORNER
/
CB RIM=43701
/ IE 12 DI(NE)=433.65
IE 12" DI(SW)=433.65
/ SO
/ CB RIM=43717
/ IE 4 PVC E=436.02
IE 6" PVC(SW)=4JS92 Q
% 4�4
/
% 44
/ 35' ELECTRICAL
j EASEMENT PER
AFN 7903280295
/ YKEYSTOi
i I I
LQ / CB RIM=442.16
'\ IE 12DI(NE)=439.16 CB RIM=439.03
=436\88 <
\�b
B-7
( n
CONCRETE
/ ''CONCRETE CURB
.--- ------__-F-L----- L�/1L1U 1LlL/1/ !1
-
_ ---
-----,-� ------- -
`SO
Q' T FOUND REBAR CAP
UNREADABLE AT CO
11
a
-� •" /
0_ SSCO RIM= 429.16' 'I
236TH ST. S.
M � a
ANCNDR FAlzr
/ AFN 84052f0087 -
N 86'J651" W 181.43,
/ I
I , IE 12' CMP(W)=4*42
IE 12" CUP(E)=413.16
IE 12" CMP(S)=413.16
/ LI I {� I "�
B-13 � i �iB-9 1:7
1
s� /h PARCEL A I INGwEss, EcaEss
IY BOUNDARY LINE AFNAND PARKING r
/T \ I AFN 7812060189 i,
ADJUSTMENT
B-1 / AFN 9810.125004 I I SDMH RIM=418.35
/ 1 I IE 12 CUP N=415.50
/ / 1 00451900100201 I I IE 12' CMP(S)=415.50
IX. / 11.31 SF s I I B-2 r
COMMERICbll �b l 0.26 AC _ I I Y
BUILDING / / 12360
BOL.I c� I i 00451900100204 Ip
XYYCIIii/ /
I. I EA SEWER & ORM
EASEMENTS A��IT 1588234
AND AFN 15882J8 '
/ 20' INGRESS, EGRESS
AND PARKING 189EASEMENT `r!' I CB RIM=418.20
AFN 7812060'Tb
B-$ INGRESS, EGRESS IE 12 CMP N =415.7
yI AND PARKING IE 12' CMP(S)=415.70
��- ��/�� i�� it AFN 7812 189 IE 6�CMP(W)=415.66
✓ SDMH RIM=429.65
G IE 6 CMP E=426.70 /) I (•
✓ IE 4- PVC(N)=426.95 I a CB RIM=424.69
IE 6" CMP(W)=426.55 IE 6 CMPE=412.54'� B-1 0
I I j IE 6- CMP(W)=426.64 I IE 6" PVC(W)=412.81
W Iz IE 6" PVC(N)=427.18 I I IE 6' CMP(SW)-422.88 \ m
t U
j PARCEL B j l I I
$ I BOUNDARY LINE I I
3 I ADJUSTMENT
AFN 9810125004 I I e
j 00451900100203 ELECTRICAL
I� 34,881 SF I EASEMENT ASPHALT
AFN 7905180203 I I I
0.80 AC I CB RIM=4I8.59
rrh 1 E 12' ;i B-3 • I
SUNSET BUILDING IE 6' CMP('_.., .. _._J
m c
123607
ARCEL C
OF'EDMONDS
S-23-88
880921.0451
i
1
N 88'J7'03' W JJT07' I
{ ; FOUND
NO
B-11 �-----------I------i---�-+
/SSMH RIM= 417.45' S
INV 8" P✓C(N)=410. 05' \ I� 1IY
INV. 8' P✓C(s)=412.J5' 11I\
/ INV. 8" P✓C(SW)=412.J5' CAPPEDI II II I
10' SANRARI��SEWER-�-:I�
UT/LDY1 6o`ENT
AFN 20020 60z42 I 1 T
/ 15' STtASEORMIYTTER
GRAVEL AFN 20020 60241 i III i,
\ / I I
\
15' STORM WATER ESMT. 10' S HOARY S '
B-12
AFN 200201160141 � & URLITY FASEM III m
---.1-- -� - I B-4 AFN 2002I01160 , I -f
--
--hr--- -/--1---------1------ I`r,
CHAIN,LINK FENCE _
INV. 8' PVC(E)=406.71
LEGEND
INV. 8" PVC(W)=406.96'
IN,8' PVC(S)=406.76'
/
i�
B-1
APPROXIMATE LOCATION AND ID OF
FOGUNE--
BORING COMPLETED 11/21/2020 TO
2' BRASS DISK
WITH PAVEMENT. g
,g
11 /22/2020.
1 AUGUST 2018.
'_ - _ _ _
i N 88'3651' W 1 475.34'
_ _ _
-/'SD
®B-8
APPROXIMATE LOCATION AND ID OF
SD-4/
BORING COMPLETED 12/5/2020 TO
�a
cONCNETE Gu
12/6/2020.
FOUND RERAR AND CAP CO RIM=407.48
STAMPED 'WEBS 16230 IE 12 CUP W =4
0. i'(E) OF CORNER IE IE 12" CMP(E)=4
IK
I
24' EASEMENT PER PUT OF
\ I WILLOWBROOK DIV. NO. 2
\ LOT 8
I
I
I
03
V v�,
i PLAT OF
WILLOWBROOK DIV. NO. 2
VOL. 34, PG. 59
`I
I
LOT 7
I
I
I
I
I
I
I
_1_______________________________________
I
I
I
I
I
I
I
^I
I \VI
I LOT 6
I
I
I
-----I--------------------
I
I
I
40 0 20 40
% SCALE IN FEET
1
LOT 5
I
REFERENCE: TOPOGRAPHIC SURVEY PREPARED BY PACIFIC COAST SURVEYS, INC. DATED 08.16.2018.
I7/I I A IT 1 /lA rl
x=mD
(FOR m > 0.4)
1.77q m2n2
D
6h D 2 ' (m2+ n2)3
_7
D (FOR m < 0.4)
6 h
0.28q n 2
6h - D 2 (0.16 + n2)3
BASE OF EXCAVATION
q, lb per ft2
x=mD
%/x /\ //
z=nD
LINE LOAD D
PRESSURE 6h
BASE OF EXCAVATION
q, lb per ft2
6'h =(yh cost (1.1*O)
�q
6h
O 6h
PLAN VIEW OF WALL
STRIP LOADING PARALLEL
TO EXCAVATION
(yh = 27q ((3-sin (3cos 2a)
1 IAIC I llAr%
(FOR m > 0.4)
1.28q
m 2 n
6h - D '
(m2+ n2)2
(FOR m < 0.4)
6h _ q
0.2n
D
(0.16 + n2)2
UNIFORM LOAD DISTRIBUTION
6h = (Ka or Ko) q
q = Vertical pressure in psf
Ka (Active) = Tan 2(45 - 0/2)
Ko (At Rest) = 1 - Sin 0
O = 38'
6h
BASE OF EXCAVATION
APPENDIX A
FIELD EXPLORATION PROCEDURES AND LOGS
Page 1
FIELD EXPLORATION PROCEDURES
Our field exploration included thirteen borings completed between November 21 and December
6, 2020. The approximate exploration locations are presented on the enclosed Site and
Exploration Plan, Figure 1. The exploration locations were determined by measuring distances
from existing site features shown on the Boundary and Topographic Survey. Ground surface
elevations for the exploratory boring locations were interpolated from topographic lines presented
on the Topographic and Boundary Survey. As such, the exploration locations and elevations
should be considered accurate only to the degree implied by the measurement methods. The
following sections describe our procedures associated with the explorations. Descriptive logs of
the explorations are enclosed in this appendix.
Soil Boring Procedures
Borings were advanced using hollow -stem auger drilling methods by Environmental Drilling and
Holocene Drilling working under subcontract to our firm. The borings were advanced using a
Mobile B-57 truck -mounted drill rig and a D70 track -mounted drill rig. A geotechnical engineer or
engineering geologist from our firm continuously observed the borings, logged the subsurface
conditions encountered, and obtained representative soil samples. All samples were stored in
moisture -tight containers and transported to our laboratory for further visual classification and
testing.
Throughout the drilling operation, soil samples were obtained at 2.5- to 5-foot intervals by means
of the Standard Penetration Test (ASTM: D-1586). This testing and sampling procedure consists
of driving a standard 2-inch outside diameter steel split spoon sampler 18 inches into the soil with
a 140-pound hammer free falling 30 inches. The number of blows required to drive the sampler
through each 6-inch interval is recorded, and the total number of blows struck during the final 12
inches is recorded as the Standard Penetration Resistance, or "blow count" (N value). If a total
of 50 blows are struck within any 6-inch interval, the driving is stopped and the blow count is
recorded as 50 blows for the actual penetration distance. The resulting Standard Penetration
Resistance values indicate the relative density of granular soils and the relative consistency of
cohesive soils.
The enclosed boring logs describe the vertical sequence of soils and materials encountered in
each boring, based primarily upon our field classifications and supported by our subsequent
laboratory examination and testing. Where a soil contact was observed to be gradational, our
logs indicate the average contact depth. Where a soil type changed between sample intervals,
we inferred the contact depth. Our logs also graphically indicate the blow count, sample type,
sample number, and approximate depth of each soil sample obtained from the boring, as well as
any laboratory tests performed on these soil samples. If groundwater was encountered in a
borehole, the approximate groundwater depth, and date of observation, is depicted on the log.
The boring logs presented in this appendix are based upon the drilling action, observation of the
samples secured, laboratory test results, and field logs. The various types of soils are indicated
as well as the depth where the soils or characteristics of the soils changed. It should be noted
that these changes may have been gradual, and if the changes occurred between sample
intervals, they were inferred.
Page 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 438 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
6-1
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
8 U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
2 1/2 inches of asphalt over
IIII ',II
IIIIIIIII
IIII ..-
Loose, moist to wet, orange and dark brown, silty
IIII III
IIIIIIIII
Illlii
7-I-I-rrt-rrt
-r-r-r-r-rTTT r
-rrrrr r r -
SAND/sandy SILT, some gravel, trace charcoal. (Fill)
--------------------------------------------
S-1 181,
III
�OTTT
IIIIIII
TTTTTTT--
9
GSA
Loose, wet, orange, silty SAND, with gravel. (Weathered
Glacial Till)
J J J 1
IIIIIIIII
1 L.L 111111
IIIIIIIII
LL LLL L
IIIIIII,
,�
-----------------------------------------
T
Medium dense, moist, gray with moderate orange mottling,
9 Y 9 9,
silty SAND, some gravel. (Weathered Glacial Till)
s-z I 18^
11
Q +-�-i-F+
I I
+{+++++
IIIIIIIII
+++I-+-+ +�
IIII
30
IIIIIIII
IIIIIII
-t-17 t f-t-r-r-r
11IIIlI
IIIIIIIII
rtrt7 rtT7 *trt
IIIIIIIII
IIII
t t.t r r
(IIIIIII
Very dense, moist, gray, silty SAND, some gravel.
(Unweathered Glacial Till)
Very dense, moist, gray, silty SAND, some gravel.
(Unweathered Glacial Till)
S-3 T 18„
11
T
S-4 18
1
IIIIIII
0-I--7-r-7
------------------------
IIIIIIIII
-TT-T-T-TTTTT
1 1
IIIIIII
TTTTTTT `
74
71
II1111�11
lilll1i11
(IIIIIII
-t(IIIIIII
-I111 + f-F
-(IIIIIII
IIIIIIIII
-+-t t t t t.t..t t
IIIIIIIII
I1i111'...
t t+ t - .'.. ,...
IIII '.
Very dense, damp, gray, SAND, with silt, some gravel
T
S-5 11 181,
-(IIIIIII
IIIIIIIII
IIIIIII:
89
'...(IIIIIII
''...11IIIlI
t t r-rT-r-rTT
IIIIIIIII
IIIIIIIII
-r-r-rTTTr
IIIIl11
IIIIIII
-I-1-G-4-4-4-1
-1---a--1---1--1--1--1-
-4--4--1--1--1- 1- - _..
IIIIIIIII
IIII
Large rock at -17 1/2 feet.
IIIIIIIII
IIIIIII
-++-4-4
IIIIIIIII
IIIIIIIII
+++++++++
IIIIIIIII
IIII�....
++++-
IIII ...
Auger refusal at approximately 17 1/2 feet.
IIIIIIIII
IIIIIIIII
-trt-r-r-fiTTT-r
IIII
trrrr r t
No groundwater seepage observed ATD.
IIIIIII
1
IIIIIIIII
IIIIIIIII
T��'44
'..IIIIIII
T TTTTTTTT
III�IIII�
TTTTTTTT
IIIIIIIII
IIIIIIIII
IIIIIIIII
llllllll
-.,... -I-4-F-F-44
IIIIIIIII
IIIIIIIII
44+44-I-+- -+4-
Li. L...L..
IIII II
IIII II
4-4-4-4-4-1- I-...i-•.I-.
..11lllll
'Illlllll
IIIIIIIII
IIIIIIIII
I1111-t-t-t-r
IIIIIIIII
IIIIIIIII
fit� t t t..ttt
IIIIIIIII
IIII
tttt
Illlii '
IIIIIIIII
IIIIIIIII
(IIIIIII
T1TT7T77
77777TTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_�
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Aprox. 420 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-2
Date Drilled: 11/22/2020 Drill Rig: Mobile Drill B57 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
a U)
E J `
m
co
o
0)
Standard Penetration Test
E
The stratification lines represent the approximate boundaries
Z 0- o
a
Q Hammer Weight and Drop:
U
�
between soil types. The transition may be gradual. Refer to
Q 0
�
report text and appendices for additional information.
A
2
m
(D
0 20 40 60
2 inches of asphalt over
Drilling action suggests cobbles/gravel in upper 3 feet. Moist,
brown, gravelly SAND, some silt in cuttings.
1 III III
1 1
IIIIIIIII
Illlii
11 1-1-144
(IIIIIII
-r-r-r4,111 r r
IIIIIIIII
r11 14 r r -
IIIIIII
gravelly
Dense, moist, brown, ravel) SAND, some silt. Gravel in
3_1 I q"
1 -
31
-f-ITT��-f7
77 T TTjTTTT
_
TTTTTTT _
shoe. (Fill)
�?
1 1 1 1 1 1
Medium dense, wet, dark brown, silt SAND, some ravel,
Y 9
abundant decayed organics, trace charcoal. (Fill)
1I
S-2 10"
�JJL���1
IIIIIIIII
-(IIIIIII
111111111
IIIIIIIII
IIIIIIIII
1LLLLLL'_
IIIIIII
(IIIIIII
12
�++++++++
+++++ ++
illllllll
-IIIIIII
IIIIIIIII
(III
Wet, dark gray -brown, silty SAND, some gravel. Large rock at
i-17trt�rtrtrt
IIIIIIIII
rtrtt t t t ttt
(III
t t r r r
-7 feet impeded auger. (Blowcount likely overstated, pounding
m-rock.1QALaaove /]_----------------------------
S-3 I 3"
I I I I I I I I I
TT I f
I I I I I I I I I
77TTTTTTT
I I I I I I I
TTT-TTI-T F iF
50/6"
(Medium dense Glacial Till)
Very dense, damp, gray, SAND with gravel and silt. Orange-
brown oxidation mottling in top 4 inches of sample interval,
S-4 14"
IIIIIIIII
IIIIIIIII
I I I I I I I I I
IIIIIIIII
IIIIIIIII
I I I I I I I I I
IIIIIIIII
IIIIIII
I I I I I I 1 I
76
GSA
QI
'..1111111
IIIIIII
-
IIIIIII
gray below. (Weathered Glacial Till over Unweathered)
IIIIIIIII
_f_tt+tt.t.tt
IIIIIIIII
tt.t
(III '.
Very dense, damp, gray, SAND with silt and gravel.
T
s-5 I 10"
'.IIIIIIII
IIIIIIIII
Illllli
50/6"
GSA
7-1T-i-i ��
'..IIIIIII
'..IIIIIII
_
t 7-r-rT-r-rTT
IIIIIIIII
IIIIIIIII
-r-r-rTTTr
IIIIIII
IIIIIII
1 1 17 11
i T 1 T TTT_
T_ 1 1; 1 1 7_
1 1 1 1 1 1 01
i
1
(Unweathered Glacial Till)
4
IIIIIIIII
-
IIIIIIIII
G -
(III
Very dense, damp, gray, silty SAND with gravel.+++-4-44
IIIIIIIII
IIIIIIIII
+++++++++
(III
++++-
(Unweathered Glacial Till)
S-6 I 4"
1 1 1 1 1
�7rtrtrtrtrt
-firt-f rt t t-rt-r
I I
1 1
tr tr t-r
50/6"
Auger refusal at approximately 18 feet.
No groundwater observed ATD.
IIIIIII
-1-177-1-t--T
1
IIIIIIIII
IIIIIIIII
lliiili
777- 7TTTT
II1�1II1�
TT7TT77r7
1II1�1III
IIIIIIIII
llllllll
IIIIIIIII
IIIIIIIII
(III '.
Illlii
..11lllll
IIIIIIIII
(IIIIIII
'Illlllll
IIIIIIIII
IIIIIIIII
fittttt.+tt
IIIIIIIII
(III
tt rr
Illlii '.
1111-71
74444T44
TTTTTTT :-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits B_2
Geoprofessional Consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 419 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-3
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
a U)
E J `
m
co
o
0)
Standard Penetration Test
E
The stratification lines represent the approximate boundaries
Z 0- o
Q
U
�
between types. The transition be Refer to
a
Hammer Weight and Drop:
soil may gradual.
Q 0
�
report text and appendices for additional information.
A
2
m
(D
0 20 40 60
Approximately 2.5 inches of asphalt over
Damp, light brown, silty SAND with gravel. (Fill)
III ill
IIIIIIIII
Illlii
7-I�-i-i-rrt
rt-r-r-r-r-r-rT r-rr-rrr
IIIIIIIII
r r-
IIIIIII-
Loose, moist, light brown mottled with gray, moderate Oran e-
9 Y, 9
9„9
S 1 I
..IIIIIIII
� �7
7777 TTTTT
TTTTTTT
g
brown oxidation staining, silt SAND, with Fill
g, Y gravel. ( )
I
I 1 1 1 1
--------------------------------------------
11JL���1
''I11���1�
1 .i i L L i.L L
- L LLLLL v
Medium dense, wet, brown sandy GRAVEL, with silt, some
IIIIIIIII
IIIIIII-.'.
wood fibers. (Fill)
T
----------------------------------------- ---
Medium dense, damp, reddish brown, fine SAND, some silt
S-2 10„
11
-I-4-4-F-I-4
-H-++++++
+4-11 -11 _..
20
1 1 1 1 1 1 1 1 1
-IIIII
1 1 1 1 1 1 1
II
1 1 1
III
1,
and gravel. (Fill)
.
i-l7Itrt11rtrtrtIIIIII
IIIIIIIII
1TIt tIt t t t l-
IIIIIIIII
r
IIIIIII.
`
`------------------------------------------
S-3 15"
I-iIIIIIIII
�TT_7Tk77
IIIIIIIII
77TT-T TTTTTTTTTT
IIIIIII _
31
GSA
Dense, wet, light brown with moderate orange -brown oxidation
1 1 1 1 1 1� 1 1
l I 1 1 I 1 1
l l i l l l l
staining,silt SAND with ravel. Weathered Glacial Till
Y g ( )
Dense, damp, gray, gravelly SAND with silt. (Unweathered
Glacial Till)
S-4 12^
IIIIIIIII
I I I I I I I I I
IIIIIIIII
I I I I I I I I I
L L L L'_ _
IIIIIII
I I 1 1 1 1 1
47
GSA
(
'....IIIIIII
IIIIIIIII
4,
Ili
'..IIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
III1 "...'...
IIII '.
Very dense, damp, gray, silty SAND with gravel.
T
s-5 I 12^
'.IIIIIIII
IIIIIIIII
Illllli
50/6"
7-i�-i-i ��
'..IIIIIII
'..IIIIIII
71
t 7 r-rT-r-rTT
IIIIIIIII
IIIIIIIII
-1
-r-r-rTTTr
IIIIIII-
IIIIIII.7
T i i 1T71
17 I T T TT_
T_TT- T T.
(Unweathered Glacial Till)
IIIIIIIII
IIIIIIIII
11I1�......
IIIIIIIII
++ -44
IIIIIIIII
IIIIIIIII
4+4++++++
IIIIIIIII
IIII
+++ -
IIII '...-
IIIIIIIII
-I��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtrtrt*rtt
IIIIIIIII
trrrrr..
IrT_
(IIIIIIIII
-IIIIIIII
1-177-1-7-T7
-1�111111
IIIIIIIII
TTTTTTTTT
III�II�I�
Illlllll
TTTTTi-T '-
I�II�II-
Very dense, damp, gray, silty SAND with gravel.
T
(Unweathered Glacial Till)
S-6 I 12
50/6"
l l l l l
Boring completed at approximately 21 feet.
IIIIIIII
IIIIIIIII
Illlii
No groundwater observed ATD.
+
++-+-++++++
+++i- -
IIIIIIIII
IIIIIII
Boring left open after completion from 09:10 to 16:00. Boring
caved in at approximately 12 feet. No groundwater observed
.IIIIIII
11-t�_t t t
IIIIIIIII
fitt t t t tt t
IIIIIIIII
t t t r
Illlii
in upper 12 feet of boring at end of day.
T
7TTTTTTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits B_3
Geoprofessional Consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 422 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-4
Date Drilled: 12/6/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
1 to 2 inches of crushed gravel over
IIII ',II
IIIIIIIII
IIII ..-
-IIII1111
IIIIIIIII
Illlii
--i-I-I�-i-i-rrt
-IIIIIIII
rt-r-r-r-r-r-rT r
IIIIIIIII
-rr-rrr r r -
Illlllli
Medium dense, moist, brown, ravel) SAND with silt. Fill
gravelly (Fill)
S_1 I1a
1 1 1 1 1 1
26
GSA
����TT
ITT+1TT
T
1 1 1 1 1 1 1
--'-"'-----"'---'-"'---'-"'---'-"'---'-
Medium dense, wet, gray with brown mottling, ravel) SAND,
g Y g� gravelly
some silt. (Weathered Glacial Till)
T
S_2 I 12„
11
-IIIIIIII
1.11111.1L
IIIIIIIII
1LLLLLL'_
IIIIIII
30
111111111
1 1 1 1
I I-I-I-FQ+
1 I 1 1,41 I 1
-{++ +++
1 1
+++-++
IIIIIIII
(IIIIIIIII
IIIIIIIII
IIII
_i7tt rtrtrt
IIIIIIIII
rtrtttttttt
IIII ..
rt.trr,, ,
Verydense, moist, gray, SAND with silt and ravel.
9 Y 9
(Unweathered Glacial Till)
Very dense, moist, gray, SAND, with gravel and silt.
(Unweathered Glacial Till)
s3 1 1s^�1
I
T
S-4 18
I
1
1 1 1 1
1 1 1 1 1 1 1
74
GSA
���T�T
IQ[ IIII
II I I I I I I I I
TTTTTTT
III [[III
I I I I I I III , III III
TTTTTTT`
IIIIIII
..
III IIl IIl IIl IIl I Il IIl _v'i.
+
llllllill
lillllill
Illlllll
IIIIIIII
IIIIIIIII
Ililll'...
Very dense, moist, gray, SAND, with gravel and silt.
(Unweathered Glacial Till)
T
s-5 1a
11
-illiiili
iilliiill
Illllli
72
t t r-rT-r-rTT
-r-r-rTTTr
IIIIIIIII
IIII
IIIIIIIII
IIIIIII
IIIIIIIII
llil�......
IIIIIIIII
-I��rtrtrtrtrt
iilliiill
rtrtrtrtrtrt*tt
IIII
trrrrr
Very dense, moist, gray, SAND, with gravel and silt.
-177-1-7-T7
++TTTTTTT
TTTTTi-T '-
(Unweathered Glacial Till)
s-6 16^
50/6^
Boring completed at approximately 20 1/2 feet.-
IIIIIIIII
IIIIIIIII
IIII
No groundwater observed ATD.
11 ��
iilliiill
444 t t t.tt 1
iiil
tfi r r;
T1TT�T�T
?+TTTTTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_4
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 437 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-5
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
2 to 4 inches of sod over
'..II '..
IIIIIIIII
IIII ..-
Light brown with gray mottling, silty SAND with gravel.
III
7
IIIIIII
- r rtrt r
Illlii
rrrrr r r -
(Weathered Glacial Till)
--------------------------------------------
Very dense, wet, gray, silty SAND, some gravel.
Unweathered Glacial Till
()
Very dense, moist, gray with trace orange -brown oxidation
S-1 6"
1n 12"
S-2 I ^ 10
Q
O
.........
IIIIII
TTTTTT
1 I a
11.11111.1 L
''...illllll
IIIIIII
TTTTl-1-T -
1 1 1 1 1 1
1LILLLL v
IIIIIII-
IIIIIIII
82
50/4"
GSA
bl l l l
staining, silty, sandy GRAVEL. (Unweathered Glacial Till)
1
++�
I111111111
++++
..illll
+++ -+-1—
IIII
IIIIIIIII
-i-I17��rtrtrt
..11lllll
IIIIIIIII
rtt1-tttt�-t
IIIIIIIII
IIII
ttrrr , ,
IIIIIIII
Very dense, moist, gray, SAND with silt and gravel.
(Unweathered Glacial Till)
Very dense, moist, gray with trace orange -brown oxidation
T
s-s 11 is
T
S-4 I 12°
IIIIIII
Ol -1 77
II
I„II
i�lillilil
I I I I I I I I I
IIIIIIIII
-77-T�TTTTT
III IIIII
II,IIIII,II
71IlIIlIT
I I I I I I I I I
IIIIIII
TTT-TTTT-
IIIIIII
IIIIILL!
Tiiiilll
I I I I I I I I
ss
50/6"
GSA
staining, silty SAND with gravel. (Unweathered Glacial Till)
-I +
111111111
+ ++ +
IIIIIIIII
+
IIIIIII
-IIIIIIII
--I11-" _f _ft
IIIIIIIII
IIIIIIIII
11-tttt.t.t+
IIIIIIIII
Illl�i
IIII '.
Very dense, moist, gray with trace orange -brown oxidation
S-5 I 12^
IIIIIIII
IIIIIIIII
III111�
50/6"
7TT1rt11
IIIIIII
IIIIIII
"TTTTTTT
IIIIIIIII
IIIIIIIII
-r-r-rrr4
IIIIIII
IIIIIII
staining, silty SAND with gravel. (Unweathered Glacial Till)
IIIIIIIII
IIIIIIIII
ilil
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII
IIII
-i��rtrtrtrtrt
IIIIIIIII
rtrtrtrtrtrt*rtt
IIIIIIIII
III
trrrrr..
Illllllli
IIIIIIII
IIIIIIIII
IIIIIIIII
-177-1-7- -T
'..IIIIIII
TTTTTTTTT
III�IIII�
TTTTI-TI- '-
IIIIIII
Very dense, damp, gray, silty SAND with gravel.
s-s 2 5^
so/s°
(Unweathered Glacial Till)
IIIIIIIII
IIIIIIIII
IIII..............
S-7 I 6"
IIIIIIIII
IIIIIIIII
IIII
50/6"
'......
Boring completed at approximately 22 1/2 feet due to auger
'..IIIIIII
-1-11 _t_t_t
IIIIIIIII
11 t t t t t"
II
44;
refusal.
i
No groundwater observed ATD.
(IIIIIIIII
IIIIIIIII
IIII
IIII
7TT7TTTTT
TTTTTTT-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_5
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 447 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-6
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
,1/2-inch of asphalt.
`------------------------------------------;..��-F...-i.--}-i--...tr
trt-i-� f
Loose, wet, gray, SAND. (Fill)
Loose, wet, -reddish brown, silty SAND. (Fill)- - - - - - - - - - - - - -
---- -- ---- --- --
S-1 I 14"
IIIII ill
1111
11 1 1 1 I 1 1
IIIIIIIII
44411
1 1 I 1
Illlii
7
11 144
IIIIIIIII
IIIIIIIII
I'l- r
IIIIIIIII
IIIIIIIII
-
111 1 r r r---------------------------------------------
IIIIIII-
IIIIIII
T�T�7
II I1 1
77777TTTT
1I1111�11
TTTTTTT -
111111
Loose, wet, gray mottled with brown, silty SAND with gravel.
1
-I 171111 1 11
IIIIIIIII
LI i, I , t
IIIIIIIII
i L L L >_ LL v
1111111,
(Weathered Glacial Till)
Dense, moist to wet, gray with trace g y race orange -brown oxidationS-2
staining, SAND with silt and gravel. (Weathered Glacial Till)
16"
37
GSA
�+ �+
++++++
+++++ +
1111111111
IIIIIIIII
IIII
IIIIIIIII
-17yrt11rtrtrt
IIIIIII
IIIIIIIII
rtrtrttttttt
IIIIIIIII
IIII
ttrrr,,,
IIIIIII
Very dense, moist, gray with trace orange -brown oxidation
staining, silty SAND with gravel. (Unweathered Glacial Till)
Very dense, moist to wet, gray with trace orange -brown
oxidation staining, silty SAND with gravel. (Unweathered
s-3 12"
S-4 181,
I
III11
-� �-�,-��
I I I I I I I I I
IIIIIIIII
I I I I I I I I I
IIIIIIIII
47 �TT7TTT
I I I I I I I I I
t.T-iT1 1111
i.iTTiTi
I I I I I I I I I
IIIIIII
TTT rTTr `
I I I I I I I
1111111
TTTTiii�
1 1 1 1 1 1 1
5oi6��
53
GSA
_I'�+Q�
++++ +
+ +
Glacial Till)
-IIIIIIII
-+t1-t t t.t.t t
IIIIIIIII
t t.t t - ,
IIII '.
Very dense, moist, gray, sandy SILT, some gravel over silty
T
S-5 I 12^
-IIIIIIII
IIIIIIIII
Illllli
50/6"
'..IIIIIIII
'..IIIIIII
-TT
-t-r r-T77TTT
IIIIIIIII
IIIIIIIII
-r-r-rrrrr
IIIIIII-
IIIIIII-
T
77777T_T_
T_TT-TT.
11
SAND with gravel. (Unweathered Glacial Till)
IIIIIIII
IIIIIIIII
IIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII
IIII '...-
IIIIIIIII
��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtrtrt-rt--r
IIIIIIIII
IIII
trrrt-
1111111111
IIIIIIII
IIIIIIIII
IIIIIIIII
-
-177-1-7-f7
'..IIIIIII
TTTTTTTTT
III�IIII�
TTTTTT
IIII�II-
Very dense, moist, gray, silty SAND with gravel.
T
S-6 I 13"
50/6"
QY
(Unweathered Glacial Till)-
IIIIIIIII
IIIIIIIII
iii1......
llllllll
IIIIIIIII
Illlii
..11lllll
''111���1�
IIIIIIIII
IIIIIIII
1-r11�����
IIIIIIIII
IIIIIIIII
fittttt.+tt
IIIIIIIII
IIII
tt-rr�-
Illlii '.
(Driller added 3 to 5 gallons of water to assist in clearing����T��
IIIIIIIII
IIIIIIIII
IIIIIII
7T77TTTTT
TTTTrTr -
cuttings.)
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_6
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 2
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 447 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-6
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D 0
co
o
U
—°
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
20 40 60
Very dense, moist, gray, silty SAND with gravel.
s-7 51,
sois
(Unweathered Glacial Till)
III
III
IIIIIIIII
IIIIIII'
(Drilling action suggests the presence of cobbles between
( 9 99 P
r r
1 1 1-1-1
r l I I i I-
l l 1 1 1
-1-T-1-1 -T.-1.-1 -1
1 1 1 1 1
7777777 -,
approximately 26 and 28 feet)
I
LLLLLLLLLJLLJLJ
(IIIIIIII
I I I I I I I
I I I I I I I I I
IIIIIIIII
I I I I I I
L-JLJL1
IIIIIII'
IIIII
1+11—
(IIIIIII
III
1—.I i I--I._I_I
IIIIIIIII
IIIIIII'
Very
ry densedamp, gray, silty SAND with gravel.
,
S-8 = a^
.IIIIIIII
IIIIIIIII
IIIIIII'
sofa
1
1 1 1 1 1 1 1
Glacial Till)
IIIIIIIII
�rt4-1
IIIIIIIII
rt4(Unweathered
IIi1111'
i .i
iiliiiiiiiii1111
LLLLLLLLJLLJL�
i .i 1- i_I-l_i__l_i_i
i i i. i i i
7777777
i i 7 7 7 7 T_,
LJLJLaJ
Very dense, damp, gray, sandy GRAVEL with silt.
Unweathered Glacial Till )
s-s s^
2
sois°
MINN'IIIIIII
IIIIIIIII
Auger refusal at approximately 36 feet.
'IIIIIII
I I I I I I I
I I1 1 1 1 1
IIIIIIIII
IIIIIII
No groundwater observed ATD.
IIIIIIIII
I I I-t-i I
-i-17 7 rt 7 7 7
IIIIIIIII
rtrt rt 7-t 7 t
IIi1111'
��777 77-1
il� iili
7777777
iii1111
Illllllll
IIIIIIII
I Ilia
111 i
IIIIIIII
.IIIIIIII
I I
111111111
I I I I—
IIIIIII'
4—F—+444
IIIIIIII
IIIIIIIII
IIIIIII'
r.r
IIIIIIIII
IIIIIII
r l I—t—I—I I—
llllllll
—I.—I—I � y rt.�.� 7
IIIIIIIII
IIIIII'
rt rtrt7777
IIIIIII'
llllllll
llllllll
—17-177-177
IIIIII'
7F7Fl-7-7
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
7777777
IIIIIII'
L.L.IIIII
IIIIIII'
IIIIIIIII
IIIIIIIII
�.�1—I
IIIIIIIII
I—Iti I--l—I.-1-4�-44-�
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIII'
IIIIIII'
44.4444+1
IIIIIII'
llllllll
IIIIIII'
IIIIIIII
IIIIIIIII
IIIIIII'
IIIIIIII
�rr1l-t-i-I
1--i-i-177rt.�.77
IIIIIIIII
IIIIIII'
rtrtrtrtrtrtrt;
_....
7-T7-T77-T
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. =Consolidation Test N measurement.
ZipperGeo BORING B_6
Att. = Atterberg Limits Geoprofesslonal consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Page 2 of 2
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 440 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-7
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
E
SOIL DESCRIPTION
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
PENETRATION RESISTANCE (blows/foot)
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
Approximately 6 1/2 inches of asphalt over
2 inches of crushed gravel base course over
I I I I I I
I I I I I I I I I
I I I I
Loose, moist to wet, orange -brown, SAND with silt, some
IIII III
IIIIIIIII
4444-fTTTY
Illlii
11 1-1-144
1114 r r -
gray_el,tracecharcoal_�Fil�_________________________
Loose, moist to wet, orange -brown, SAND with silt, some
g
s-� T �s
I
i7f�
`'
7T T T TT TT
TTTTTTT
g
g ravel.
� i
-------------------------------------------
Verydense, moist, tan -gray, SAND with silt and ravel.
g Y, g
(Unweathered Glacial Till)
1
T
S-z I 181
11+�
JLL_JJI
IIIIIIIII
IIIIIIIII
I-LLILLl.L1
IIIIIIIII
IIIIIIIII
1LLLLLLL
IIIIIIII
IIIIIII-�'..
ss
GSA
+
+{++++++
+++ + +
(IIIIIIIII
IIIIIIIII
IIII
IIIIIIIII
-+ , trtrt-r-r
IIIII
IIIIIIIII
rtrtrt t t t ttt
IIIIIIIII
IIII
t t.- r T-
IIIIIII
Very dense, moist, yellow -tan, SAND with silt, some gravel.
(Unweathered Glacial Till)
Very dense, moist, gray with light -orange mottling, silty SAND
with gravel. (Unweathered Glacial Till)
s-s 12°
S-4 181,
IIII
1 1017-7-777-77TT
IIIIIIIII
TLLLI.
I I I I I I I I I
IIIIIIIII
TTTTT
IIIIIIIII
LLT.�.T.T.T.T.T.
I I I I I I I I I
IIIIIII
TTT-TTI-T `
IIIIIIII
TTT �.�:...
I I I I I I I I
Sois"
ss
GSA
IIIIIIIII
Q
+++++++
IIIIIIIII
+ -
IIIIIIII
IIIIIIIII
1 11 �t
IIIIIIII
IIIIIIIII
-+t1-ttt.t.tt
IIIIIIIII
Ililll'...
IIII
Very dense, moist, gray, SAND, with silt some gravel.
S-5 I s
IIIIIIII
I-I-1-1T-irt
IIIIIIIII
IIIIIII
50i6°
��
..'...IIIIIIII
t t r-rT-r-rTT
IIIIIIIII
-r-r-rTTTr
IIIIIIII
rII
1119111
1
(Unweathered Glacial Till)
a
IIIIIIII
IIIIIIIII
IIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
lilt
+++ -
IIII
IIIIIIIII
-I��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtrtrt*rtt
IIIIIIIII
IIII
trrrrr.
IIIIIIII
IIIIIIII
7-77-17 f7
-IIIIIIII
IIIIIIIII
++TTTTTTT
III�IIII�
IIIIIIII
TTTTT77 'F
IIIIIIII
Very dense, damp, gray, SAND with silt, some gravel.
s-s 2 s^
10i5"
(Unweathered Glacial Till)--
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII
IIIIIIII
....IIIIIIII
IIIIIIIII
IIIIIIII
IIIIIIIII
IIIIIIIII
fittttt.ttt
IIIIIIIII
IIII
tfitt--
IIII��
IIIIIIIII
IIIIIIIII
IIIIIIII _...
T11T�T�7
?+TTTTTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_7
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 2
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 440 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-7
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
E
SOIL DESCRIPTION
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D 0
PENETRATION RESISTANCE (blows/foot)
co
o
U
—°
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
20 40 60
Very dense, damp to moist, gray, SAND with silt and gravel.
S-7 6"
50/6"
(Unweathered Glacial Till)
1
III
IIIIIIIII
IIIIIII'
.ill
Hi iii
F.F F 1 I I i L-
���� -T -17 -
7777777
LLLLLLLL
IIIIIIIII
��J��JJJ
IIIIIIIII
1JJJJ11
IIIIIII'
IIIIIIIII
1+11- 1-.i i I--I._I_I
illlllll
IIIIIIIII
IIIIIIIII
IIIIIII'
IIIIIII'
Very dense, moist, gray, silty SAND, some gravel.
S-8 I 6"
.illlllll
IIIIIIIII
IIIIIII'
50/5"
(Unweathered Glacial Till)
r1 1 1-i-1 1
111ii11
r-1-l-1yrt11 7��
IIIIIIIII
rtrt4-1-4
IIIIIII'
liiiiii
ii1111''
_ _
I—r1-7-7F
I11iii1
I II
_iii i__..
Illi
Illi
7777777
i iiiiTT_ ,
IIIII
ii1111'
IIIIII'
Very dense, damp to moist, gray, SAND with silt, some gravel.
S-9 I 6"
I
I
50/6"
(Unweathered Glacial Till)
IIIIIII
IIIIII
III
.rFI I—t-1_1 I--L_I-177rt
iiii
_�.rtY4711
T777
L.L LI I_f_L_I I_
111111111
_L_L_IJ J JJ.L �
i�i ii�i�
11.11111 _ ,
IIIIIII'
S-10 0"
illllll�
llllll'
L50/0--
Boring completed at approximately 40 feet.
illllll
ii
IIIIII'
No groundwater observed ATD.
lllllll
�4444 -
iiliiiil
r.rr1 1-i-i-1 �
iiliiiil
111i
��rt , ,
111i
ii1111
*rtrt777rt
ii1111
iiliiiil
111i
17-1- _.
111i
Illi
ii1111
-777777 _
ii1111
111111'
FT77 -r-7
IIIIIIIII
iiliiiili
—I—I.-1 -4 4 -�
IIIIIIIII
iii1111
4 4.4 4 4 4+ 1
IIIIIII'
illlllll
IIIIIIIII
IIIIIII'
illlllll
IIIIIIIII
IIIIIII'
illlllll
�rF11-t-i-11--i-i-177rt.�.77
IIIIIIIII
IIIIIII'
rtrtrtrtrtrtrt;
_....
777-T77-T
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. =Consolidation Test N measurement.
ZipperGeo BORING B_7
Att. = Atterberg Limits Geoprofesslonal consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Page 2 of 2
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 429 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
6-8
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
a U)
E J `
m
co
o
0)
Standard Penetration Test
E
The stratification lines represent the approximate boundaries
Z 0- o
a
Q Hammer Weight and Drop:
U
�
between soil types. The transition may be gradual. Refer to
Q 0
�
report text and appendices for additional information.
A
2
m
(D
0 20 40 60
Approximately 3 inches of asphalt over moist to wet, brown,
silty SAND. (Fill)
IIII ',II
IIIIIIIII
IIII ..
Boring encountered a 1-inch diameter PVC pipe with a red -
coated copper wire protruding at approximately 2 feet below
grade. Wire did not appear to be live. Water drained from the
damaged PVC to fill the boring. Bailed water from hole to
observe the damaged utility. No bedding observed around
PVC, which entered boring from the northwest. Boring
advancement halted after encountering utility.
SAMPLELEGEND
I2-inch O.D. split spoon sample
3-inch I.D. Shelby tube sample
TESTING KEY
GSA = Grain Size Analysis
20OW = 200 Wash Analysis
Consol. = Consolidation Test
Att. = Atterberq Limits
GROUNDWATER LEGEND
O % Fines (<0.075 mm)
Clean Sand
O % Water (Moisture) Content
®
Bentonite
Plastic Limit Liquid Limit
Grout/Concrete
Natural Water Content
®
Screened Casing
Apollo Apartments
n
Blank Casing
23601 Highway 99
Groundwater level at
time of drilling (ATD) or
Edmonds, WA
N
on date of
Date: December 2020 Project No.: 2361.01
measurement.
ZipperGeo BORING
B_8
Geoprofessional Consultants LOG`:
19019 36th Ave. W, Suite E
Lynnwood, WA Page 1 of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 420 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
6-9
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
E
SOIL DESCRIPTION
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
PENETRATION RESISTANCE (blows/foot)
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
Approximately 2 inches of asphalt over
IIII ',II
IIIIIIIII
IIII ..-
'.III11111
IIIIIIIII
Illlii
7-I�-i-i-rrt
rt-r-r-r-r-r-rT r-rr-rrr
IIIIIIIII
r r-
IIIIII11
Loose, wet, dark brown, silty SAND, trace to some ravel,
Y 9
wood shavingsin cuttings. Probable Fill
--------------------------------------------
_ I a
...Illlllll
�I1T��7
1=tlllll
''IIIIIIII
7T-T-TTTTTT
IIIIIIIII
.L I L L L.L L
TTTTTTT
1111111
L L LL L L L L
Very dense, wet, gray with slight orange mottling, SAND with
IIIIIIIII
1111111-..
silt and gravel. (Slightly Weathered Glacial Till)
S-2 15"
I
1 1 1 1
-Ii -4�-F-+
1
+++ -+++++
+++ - - + I-
60
GSA
IIIIIIII
(IIIIIIIII
IIIIIIIII
IIII
r-17yrt�rtrtrt
1111111
IIIIIIIII
rtrtrt t t t t�- t
IIIIIIIII
11111'..'..
t t r r r,�'
IIIIII11
Ve dense, moist to wet, gray, SAND with silt, trace to some
rY 9 Y
gravel. (Unweathered Glacial Till)
Very dense, moist, gray, SAND with silt and gravel.
(Unweathered Glacial Till)
T
S3 I 18"
11
T
s a 18
l
IIIII
IIIIIIIII
1 1 1 1 1 1 1
60
56
GSA
T T77
11 1 1't'i 11 1
IIIIIIIII
IIIIIIIII
l l l l l l l l l
7TTT-TTTTT
1 1 1 1 1 1 1 1 1
II,,,IIIII,II
7IIIIIIII
I I I I I I I I I
TTTTTTT
1 1 1 1 1 1
IIIIILL!
TTTTTF7
I I I I I I I 1
111111111
IIIIIIIII
IIII
'... III
'.. ill
IIIIIIIII
ill�lllll
IIII '...
IIII
Very dense, moist, gray, silty SAND with gravel
Very dense, moist, gray, silty SAND with gravel
T
S-5 11 18"
T
S-g 11 18"
II
r �rt��
01
(IIII
-ITT r r
Illllli i
r rrrrrr
60
60
GSA
0�J-4-4-1
IIII
111111111
-1---a--1---1--1--1--1-
IIIIIIIII
-4-4--1--1-_
IIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII�....
IIIIII111
IIIIIIIII
���rtrtrtrtrt
111111111
IIIIIIIII
rtrtrtrtrtTTrtt
IIII11111
IIIIIIIII
trrrrrrrr
IIIIIIIII
IIIIIIII
IIIIIIIII
IIIIII111
-177-1777
'..IIIIIII
77777TTTT
III�I111�
TTTTTi-T '-
1111�11-
-249-
dense, moist. aray. silty SAND with aravel
S-7 I 6"
k 50/5^
—Ve[�
Boring completed at approximately 20.5 feet.-
111111111
IIIIIIIII
IIII
No groundwater observed ATD.
,_,...-1-f-i-i-I-+
4444+++++
++4F-4-4-1-I- :_...
1111111
111111111
11111111
I1111111
I-iI'll -h-F
111111111
111111111
444 t t t..11 "1
111111111
1111
tfi 4
1111��
111111111
11111
T
7TTTTTTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_9
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 421 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-10
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
E
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
Approximately 1 1/4 inches of asphalt over
IIII ',II
IIIIIIIII
IIII ..-
-11111111
IIIIIIIII
Illlii
-(IIIIIII
IIIIIIIII
11111111
Medium dense, moist to wet, tan -gray light brown, silt
9 Y and ht 9 Y
SAND with gravel. (Possible Fill)
s_t I ts•
t3
��T ��
1'1�
7T T T TTTTT
1 I I 1 1 1 1 1 I
TTTTTTT -
1 1 1 1 1 1
------------------------------------------
Pushed a rock with sampler, blowcount overstated, low
p
recovery. Very loose to loose, wet, orange -brown, SAND with
11
S-2 3"
IIIIIIIII
-(IIIIIII
11.LILLI.LL
IIIIIIIII
IIIIIIIII
1LLLLLL'_
IIIIIII
(IIIIIII
28
IIIIIII
+
III (IIII
+++� ++++
IIIIIII
++T +
11111111
IIIIIIIII
IIII
\silt, some gravel.
-----------------------------------------
,.._I7yrt-f'-t'rtrt
..11lllll
rtt-tttt.ttt
IIIIIIIII
tt...firr '..
(IIIIIII
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
S-3 T 4"
11
T
s a l to
�II�III
Q -177
!Li
Ilillilll
1 1 1 1 1 I 1 1 1
IIIIIIIII
-7-7-TTTTTTT
iL.LiLLL1L
IIIIIIIII
I I I I I I I I I
IIIIIII
TTTTTTT `
LLLLLLLi
(IIIIIII
I I I I I I 1 I
60
55
GSA
IIIIIIIII
�
IIIIIIIII
IIII
(IIIIIII
-(IIIIIII
IIIIIIIII
IIIIIIIII
11i11'...'...
IIII '.
Very dense, moist, gray, SAND with silt and gravel
S-5 16°
-(IIIIIII
IIIIIIIII
IIIIIII:
k 50/6"
-�-I-IT-i-i ��
'..IIIIIIII
'..IIIIIII
t t r-rT-r-r rT
IIIIIIIII
IIIIIIIII
-r-r-rTTTr
(IIIIIII
IIIIIII-L
I II III
Boring completed at approximately 15.5 feet.
IIIIIII
G
IIIIIIIII
a a
G =
li IIIIIII
IIIIIIIII
IIII
No groundwater observed ATD.
1 1 1 1 1 1 1
IIIIIIIII
1 1 1 1 1 1 1 1 1
IIIIIIIII
l i 1 1
++ -
IIII '...-
IIIIIIIII
��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtTrt*TT
IIIIIIIII
IIII
trrrrr
1111111111
--IIIIIII
17f-177-1-7-T7
-IIIIIII
IIIIIIIII
TTTTTTTTT
111�1111�
IIIIIIIII
TTTTTTTTT
IIIIIIIII
IIIIIIIII
IIIIIIIII
111111111
... -I-4-F-F-44
IIIIIIIII
IIIIIIIII
44444-I--I-+-4-
L...L..
IIII _I
IIII 11
-4--4-4--I- 1- I-...F-4-
'.1111111
111111111
111111111
'Illlllll
-i-1-11tt-h-F
IIIIIIIII
IIIIIIIII
ttt t t t..ttt
IIIIIIIII
IIII
tfi-'tt
Illlii '
IIIIIIIII
IIIIIIIII
(IIIIIII
T1TT�T�7
77777TTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_� o
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: EDI Bore Hole Dia.: 8-inch
Top Elevation: Approx. 422 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-11
Date Drilled: 11/21/2020 Drill Rig: Mobile Drill B57 Logged by_: TAJ
E
SOIL DESCRIPTION
a L
E J `
Z 0- o
Q 0
A
m
io
a
�
2
(D
PENETRATION RESISTANCE (blows/foot)
co
r-
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
Approximately 4 inches of crushed gravel surfacing over
IIII ',II
-L...-i
IIIIIIIII
IIII ..-
-IIIIIIII
IIIIIIIII
Illlii
--i-I-I�-i-i-rrt
-IIIIIIII
rt-r-r-r-r-r-r r r
IIIIIIIII
rr-rrr r r-
IIIIIIII
Pushed a rock with sampler. Blowcounts overstated. Medium
dense, moist to wet, brown, silty SAND with gravel. (Possible
g_1 q^
30TTTT
ITT�T 77T
TT
TTTTTTT _
Fill or Weathered Glacial Till)�JJ���1
--------------------------------------------
Ve dense, moist, gray, silt SAND with ravel.
ry 9 Y, Y g
(Unweathered Glacial Till)
1
s-z 18"
-IIIIIIII
111111111
IIIIIIIII
1LLLL L L L
IIIIIIII
66
I I I I I I I
I I I I I I I I I
I I I I I I I
IIIIIIII
IIIIIIIII
IIIIIIII
IIIIIIIII
r-i7yrt�rtrtrt
,..IIIIIIII
IIIIIIIII
rtrtrtttt-ttt
IIIIIIIII
IIIIIIIII
trrrrrr�r
IIIIIIII
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
Very dense, moist, gray, SAND with silt and gravel.
(Unweathered Glacial Till)
s-3 T 181
11
T
s_q 18
11
IIIIIII
07-1T-T-T
III,II
Ilillllll
I I I I I I I I I
IIIIIIIII
-7TTTTTTTT
II,IIIII,II
IIIIIIIII
I I I I I I I I I
IIIIIII
TTTTTTT `
IIIIIII_,,,
TTTTTIIII
I I I I I I I I I
ss
67
++
IIIIIIII
++ ++ -+
IIIIIIIII
+ + + - -
IIIIIIII
IIIIIIII
IIIIIIII
IIIIIIIII
IIIIIIIII
Ililll'...
IIII
Very dense, moist, gray, silty SAND with gravel
S-5 T 181,
IIIIIIII
.'...IIIIIIII
IIIIIII
IIIIIIIII
rtrt7-T77-r7-r
IIIIIIIII
IIIIIIIII
IIIIII�I�
T-r-rTTTrrr
IIIIIIII
IIIIIIII
91
IIIIIIIII
IIIIIIIII
IIII
Boring completed at approximately 16.5 feet.
IIIIIIIII
IIIIIIIII
IIII it
-++++- -
No groundwater observed ATD.
9
IIIIIIIII
��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtTrt*TT
IIIIIIIII
IIII.
trrrrr
IIIIIIIII
IIIIIIII
IIIIIIIII
IIIIIIIII
-177-1777
'..IIIIIII
777T7TTTT
III�IIII�
TT7TT77T-7
IIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
+I-I+I+I-I-III--I+II-I
IIII -..
IIII
4-4I-:_...
..'IIIIIIIIIIIIII
I-4I-4I
I-4
I
-I'll
IIIIIIIII
444 t t t.tItI
IIIIIIIII
I14 I1;1I-II-
Illlii
IIIIIIIII
IIIIIIIII
IIIIIIII _...
T1TT�T�7
77777TTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B_11
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 424 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-1 2
Date Drilled: 12/5/2020 Drill Rig: Diedrich D70 Logged by_: JST
SOIL DESCRIPTION
PENETRATION RESISTANCE (blows/foot)
8 U)
E J `
m
co
o
0)
Standard Penetration Test
E
The stratification lines represent the approximate boundaries
Z 0- o
a
Q Hammer Weight and Drop:
U
�
between soil types. The transition may be gradual. Refer to
Q 0
�
report text and appendices for additional information.
A
2
m
(D
0 20 40 60
2 inches of sod mixed with crushed gravel over approximately
.4 inches of dark brown, sandy topsoil.
-----------------------------------------
-
+
in r�
iiiiii
_ -r-r-rl"i
iiii��
111 1 r r r -
Wet, reddish brown, silty SAND, with gravel. (Fill)
iiii
i
--------------------------------------------
S-1 18"
i�
I
iiiii
TTTTTT
iiiiii
iiiii
TrTTTTT-
T
44
Dense, moist to wet, gray, silt SAND with ravel. Strong
g Y, Y g g
orange -brown oxidation staining at contact. (Unweathered
�JJJ��_j1
_L_L 1L11
_LLLLLL'_
Glacial Till)
T
Verydense, moist, gray, silt SAND with ravel.
9 Y, Y g
(Unweathered Glacial Till)
s-z T 18"
1
+
++ ++++++
+++ +
78
-i-Iyrt-trtrtrt
rtrty- t t t tt t
t t.r r r,,
Verydense, moist, gray, silt SAND with ravel.
9 Y Y g
T
S3 I 15"
T T f7
7TTT T TTTT
TTrTTTT -
Ti
46
(Unweathered Glacial Till)
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
11
T
s a 1a
l
iiLLiiii
LiLLi
iTi
i
iiiiiii
66
GSA
Very dense, moist, gray, silty SAND with gravel.
S-5 I 4^
50/5"
-t-r TrT-r- 7T
-rT77rTT
(Unweathered Glacial Till)
a
G
(Drilling action suggests gravels/cobbles between++
-4 -4-4-4
+++++++++
++ +i+-
approximately 16.5 and 18 feet.
-I��rtrtrtrtrt
rtrtrtrtrtrt*rtt
i
trrrrr..
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
s-s I s"
- - -
sots"
nTT�� r7
77T r TTTT
TT-rT-r
Auger refusal at approximately 19 feet.
No groundwater observed ATD.
iiiiiiiii
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iiiiiiiii
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-+-i-- 44- —+++
++4-4-4-1-
-111 -t-t-t-t
fitttttttt
tfirr
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77777TTTT
TTTTTTT:-
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample 0 Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits B_� 2
Geoprofessional Consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Page 1 of 1
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 431 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-13
Date Drilled: 12/6/2020 Drill Rig: Diedrich D70 Logged by_: JST
E
SOIL DESCRIPTION
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D
PENETRATION RESISTANCE (blows/foot)
co
o
U
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
0 20 40 60
Approximately 5 inches of asphalt over
IIII ',II
IIIIIIIII
IIII ..-
Medium dense, moist, brown, gravelly SAND, with silt. (Fill)
'.IIIIIIII
IIIIIIIII
Illli
7 in rrt
rt r rTr
- 114rr-
--------------------------------------------
Medium dense, moist, gray, gravelly SAND, some silt.
(Weathered Glacial Till)
Verydense, moist, gray, SAND with silt and ravel.
g Y+ g
(Unweathered Glacial Till)
S-1 8"
S_2 I 18.
11
IIIIIIIII
-i-I 7�77
`r'I1
J-JJ1J 11171111i11
IIIIIIIII
IIIIIIIII
7 7T T TTTTT
1
IIIIIIIII
IIIIIII _
TTT T1-1-1- -
1
LLL1LLL!_
(IIIIIII
20
59
GSA
1 I 1 1 1 1
--I �-i-I +
Q
1 1 1 1 1 1
+++�+++++
1 1 1 1 1
+++++-+ �
(IIIIIII
(II
IIIIIIIII
IIII
IIIIII
-1I7yrt11rtrtrt
lllllll
IIItIIIIII
rtrtrt t t t� t
IIIIIIIII
Ilt r ilr rl'..'..
t ,
(IIIIIII
Verydense, moist, gray, SAND, with ravel and silt.
9 Y 9
(Unweathered Glacial Till)
Very dense, moist, gray, silty SAND with gravel.
(Unweathered Glacial Till)
S_3 I 181,
1I
T
s a 1a
l
50
55
GSA
T �7
IIIIIIIII
IIIIIIIII
l l l l l l l l l
7TTT T TTTT
II,,,IIIII,II
IIIIIIIII
I I I I I I I I I
TTTT477 -
T1
IIIIIII.
IIIIIII
( I I I I I I I
IIIIIIIII
IIIIIIIII
IIIIIII'•
IIIIIIIII
-(IIIIIII
IIIIIIIII
IIIIIIIII
llilll'...
IIII '.
Very dense, moist, gray, SAND, with gravel and silt.
(Unweathered Glacial Till)
S-5 16°
-(IIIIIII
IIIIIIIII
IIIIIII:
so/s°
'...I1111111
''...I111111
-t-r r-T77TTT
IIIIIIIII
IIIIIIIII
-rT77rTT
(IIIIIII
IIIIIII
IIIII
I II II
i
IIIIIIIII
-1l.l
4--1--1--1-
'',I1111111
IIIIIIIII
IIII
llllllll
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII
IIII '...-
IIIIIIIII
-I��rtrtrtrtrt
IIIIIIIII
IIIIIIIII
rtrtrtrtrtrt*rtt
IIIIIIIII
IIII
trrrrr..
(IIIIIIIII
-(IIIIIII
7-77-17 f7
-IIIIIII
IIIIIIIII
-777777T_
'..IIIII
IIIIIIIII
TTTTTi-T
IIIIIII
Very dense, moist, gray, gravelly, SAND, with silt.
s-s I z^
50/6"
(Unweathered Glacial Till)-
.'...1111111
..'',..IIIIIII
IIIIIIIII
IIII.......
IIIIIIIII
Illlii
lllllll
'Illlllll
IIIIIIIII
(IIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIII
�-
Illlii '.
IIIIIIIII
IIIIIIIII
(IIIIIII
_...
T11T�T�7
777TTTTTT
T:-
TTTTTT
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. = Consolidation Test N measurement. Zi pperGeo BORING
Att. = Atterberq Limits Geoprofessional Consultants B-13
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Pagel of 2
Boring Location: See Figure 1, Site and Exploration Plan Drilling Company: Holocene Bore Hole Dia.: 8-inch
Top Elevation: Approx. 431 Feet Drilling Method: Hollow Stem Auger Hammer Type: Auto
B-13
Date Drilled: 12/6/2020 Drill Rig: Diedrich D70 Logged by_: JST
E
SOIL DESCRIPTION
a U)
E J `
Z 0- o
Q 0
A
m
a
�
2
(D 0
PENETRATION RESISTANCE (blows/foot)
co
o
U
—°
m
0)
�
The stratification lines represent the approximate boundaries
between soil types. The transition may be gradual. Refer to
report text and appendices for additional information.
Standard Penetration Test
Q Hammer Weight and Drop:
20 40 60
Very dense, moist, gray, SAND with gravel and silt.
(Unweathered Glacial Till) Over -driven with D&M sampler to
obtain soil sample.
111
r.rrl_I_I_L_L-
l
�����.�.7�
IIIF
77777T7_ .
--------------------------------------------
LLLLL LL�JJJJ
JJJJJ111
IIIIIIIII
IIIIIIIII
Illllll
IIIIIIII
1+11- I-.i i I--I._I-1A��.�.�-1
illlllll
IIIIIIII
IIIIIIIII
44��
IIIIIIIII
Very dense, moist, gray, SAND with gravel, some silt.
T
S-8 I 11"
.illlllll
IIIIIIIII
IIIIIIIII
50/5'
GSA
t
11
I
_I f--L—I—I�yrt.�.�7
IIIIIIIII
IIIIIIII
rt.rt.rt*rt+r
Boring completed at approximately 31 feet.
No groundwater observed ATD.
''IIIIIIII
IIIIIIIII
—17-177-177
IIIII -
7rl-7F
111ii11
i.I I_i_I I
1 II
IIIIIIIII
Illiiiil
_I-_..
111i
777771
1ii111i'
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i i i i i iT,.
I I I I I I i
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.rrl l—t-1_I I--L_I-177rt
_ r-t 7 i.TT.
�i
iiliiiiii
ii111ii
L.LLI I f_L_I I
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illllll
L_IJJJJ.J�
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II
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IIIIIIIII
illlllll)
illllll
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illllll
IIIIIIIII
li
Ili
IIIIIIII
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.._j -F4 -1 4-i-+
IIIIIIII
r.rrl I-i-I-I
IIIIIIII
Illi
-yrt
Illi
IIIIIIII
-rtttrtttt.t.
IIIIIIII
Illi
17-7-
,
Illlllll
IIIIIIIII
11111111
-7 77777T
11111111
1 1
IIIIIIIII
IIIIIIIII
1 7r�T
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
IIIIIIIII
-4 -� -.4
IIIIIIIII
11111111 IIIIIIIII
-4 4.4 4 4 4 - .- .- .
IIIIIIIII
illlllll
IIIIIIIII
IIIIIIIII
illlllll
IIIIIIIII
IIIIIIIII
illlllll
�rrl I-t-i-I I--i-i-177rt.�.77
IIIIIIIII
IIIIIIIII
rtrtrtrtrtrtrt.t.t.
F
7�7?7-TTT
TTTT
ill)
SAMPLE LEGEND GROUNDWATER LEGEND O % Fines (<0.075 mm)
I2-inch O.D. split spoon sample Clean Sand O % Water (Moisture) Content
3-inch I.D. Shelby tube sample ® Bentonite Plastic Limit Liquid Limit
Grout/Concrete Natural Water Content
® Screened Casing Apollo Apartments
TESTING KEY n Blank Casing 23601 Highway 99
GSA = Grain Size Analysis V Groundwater level at Edmonds, WA
time of drilling (ATD) or
200W = 200 Wash Analysis N on date of Date: December 2020 Project No.: 2361.01
Consol. =Consolidation Test N measurement.
ZipperGeo BORING B_13
Att. = Atterberg Limits Geoprofesslonal consultants
LOG:
19019 36th Ave. W, Suite E
Lynnwood, WA Page 2 of 2
APPENDIX B
LABORATORY TESTING PROCEDURES AND RESULTS
Page 1
LABORATORY TESTING PROCEDURES
A series of laboratory tests were performed during the course of this study to evaluate the index
and geotechnical engineering properties of the subsurface soils. Descriptions of the types of tests
performed are given below.
Visual Classification
Samples recovered from the exploration locations were visually classified in the field during the
exploration program. Representative portions of the samples were carefully packaged in moisture
tight containers and transported to our laboratory where the field classifications were verified or
modified as required. Visual classification was generally done in accordance with ASTM D2488.
Visual soil classification includes evaluation of color, relative moisture content, soil type based
upon grain size, and accessory soil types included in the sample. Soil classifications are
presented on the exploration logs in Appendix A.
Moisture Content Determinations
Moisture content determinations were performed on representative samples obtained from the
explorations in order to aid in identification and correlation of soil types. The determinations were
made in general accordance with the test procedures described in ASTM D2216. Moisture
contents are presented on the exploration logs in Appendix A.
Grain Size Analysis
A grain size analysis indicates the range in diameter of soil particles included in a particular
sample. Grain size analyses were performed on representative samples in general accordance
with ASTM D6913. The results of the grain size determinations for the samples were used in
classification of the soils, and are presented in this appendix.
Page 1
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
C9
W
70
m
60
W
Z_
LL
50
Z
W
U
W 40
W
d
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Coarse
Medium
Fine
Silt
IGRAINED
Clay
BOULDERS
COBBLES
GRAVEL
SAND
FINE
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-1
S-1
2'/2 - 4
19.5
32.8
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-2
S-4
10 - 11'/z
6.2
20.0
SAND with
gravel and silt
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-2
S-5
15 - 16
15.9
27.2
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-3
S-3
7'/2 - 9
13.6
31.9
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-3
S-4
10 - 11'/z
5.6
23.3
Gravelly SAND
with silt
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-4
S-1
2'/2 - 4
11.7
23.3
Gravelly SAND
with silt
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-4
S-3
7'/2 - 9
7.8
27.4
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-5
S 1A
3 - 3'h
9.1
36.8
Silty SAND,
some gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-5
S-3
7'h - 9
8.0
28.1
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-6
S-2
5 - 6'/2
9.0
28.5
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-6
S-4
10-11'/2
9.9
34.6
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-7
S-2
5 - 6'/2
6.6
27.6
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B 7
S-4
10 - 11'/z
8.7
34.8
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-9
S-2
5 - 6'/2
9.2
27.3
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-9
S-4
10 - 11'/z
7.8
26.7
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-9
S-5
12'/2 - 14
8.0
30.5
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-10
S-4
10 - 11'/z
8.3
31.8
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-11
S-4
10 - 11'/z
6.7
29.1
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-12
S-4
10 - 11'/z
10.8
35.8
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-13
S-2
5 - 6'/2
7.3
28.1
SAND with silt
and gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-13
S-4
10 - 11'/z
9.1
35.4
Silty SAND with
gravel
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-13
S-7
25 - 25'/z
5.6
21.8
SAND with
gravel and silt
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments
GRAIN SIZE ANALYSIS Test Results Summary ASTM D6913
100
90
= 80
W
?� 70
m
60
W
Z
50
Z
W
tU
W 40
W
a
30
20
10
0
1000.000
100.000 10.000 1.000 0.100 0.010 0.001
PARTICLE SIZE IN MILLIMETERS
Coarse
Fine
Medium
Fine
Silt
Clay
BOULDERS
COBBLES
GRAVEL
::E
FINE GRAINED
Comments:
Exploration
Sample
Depth (feet)
Moisture (%)
Fines (%)
Description
B-13
S-8
30 - 31
4.8
7.4
SAND with
gravel, some silt
PROJECT NO: 2361.01 PROJECT NAME:
Zipper Geo Associates, LLC
Geotechnical and Environmental Consultants DATE OF TESTING: 12/9/2020 Apollo Apartments