HomeMy WebLinkAboutSims Way and Howard - Geotech Report 05.09.2009950 Pacific Avenue, Suite 515
Tacoma, WA 98402
(253) 926-2493
May 5, 2009
Prepared for
WHPacific
Geotechnical Report
Sims Way / Howard Street Roadway
Improvements
Port Townsend, Washington
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
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TABLE OF CONTENTS
Page
1.0 INTRODUCTION 1-1
1.1 PROJECT DESCRIPTION 1-1
1.2 SCOPE OF SERVICES 1-2
2.0 EXISTING SITE CONDITIONS 2-1
2.1 SURFACE CONDITIONS 2-1
2.2 GEOLOGIC SETTING 2-2
2.3 FIELD EXPLORATIONS AND LABORATORY TESTING 2-3
2.4 SUBSURFACE SOIL CONDITIONS 2-4
2.4.1 Sims Way 2-4
2.4.2 Howard Street 2-4
2.4.3 Existing Howard Street ROW – Multi-Use Trail and Rain Gardens 2-5
2.4.4 Proposed Storm Pond 2-5
2.4.5 Detention Facility – Southwest of Sims Way/Howard Street Intersection 2-5
2.4.6 Detention Facility – Logan Street Location 2-6
2.5 GROUNDWATER 2-6
3.0 CONCLUSIONS AND RECOMMENDATIONS 3-1
3.1 EARTHWORK 3-1
3.1.1 Wet Weather Considerations 3-1
3.1.2 Demolition and Clearing, Grubbing and Stripping 3-2
3.1.3 Temporary and Permanent Slopes 3-2
3.1.4 Subgrade Preparation 3-3
3.1.5 Structural Fill 3-3
3.1.6 Backfill and Compaction Requirements 3-5
3.2 UTILITY CONSTRUCTION 3-5
3.2.1 Construction Dewatering 3-5
3.2.2 Trenching and Excavation Support 3-6
3.2.3 Pipe Foundation Support 3-7
3.2.4 Pipe Bedding and Initial Backfill 3-7
3.2.5 Trench Backfill and Compaction Criteria 3-8
3.3 RETAINING WALLS 3-9
3.3.1 Gravity Block Walls 3-9
3.3.1.1 Gravity Wall Subgrade Preparation 3-9
3.3.1.2 Gravity Wall Bearing Capacity and Settlement 3-10
3.3.1.3 Wall Design Parameters 3-10
3.3.1.4 Wall Backfill and Drainage Considerations 3-11
3.3.2 Soldier Pile Walls 3-12
3.3.2.1 Lateral Earth Pressures 3-12
3.3.2.2 Soldier Pile Design 3-13
3.3.2.3 Facing Design 3-13
3.3.2.4 Wall Drainage 3-13
3.4 LUMINAIRE FOUNDATIONS 3-14
3.4.1 Luminaire Construction Considerations 3-14
3.5 PAVEMENT DESIGN 3-15
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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3.5.1 Resilient Modulus Design Value 3-15
3.5.2 Vehicular Loading and Design Structural Number 3-15
3.5.3 New Pavement Design Recommendations 3-16
3.5.4 Pavement Overlay Recommendations 3-17
3.6 STORMWATER INFILTRATION 3-19
3.6.1 Logan Street Location 3-20
3.6.2 All Other Locations 3-21
4.0 REVIEW OF DOCUMENTS AND CONSTRUCTION OBSERVATIONS 4-1
5.0 USE OF THIS REPORT 5-1
6.0 REFERENCES 6-1
LIST OF FIGURES
Figure Title
1 Vicinity Map
2 Site and Exploration Plan
3 Lateral Earth Pressures for Soldier Pile Walls
LIST OF APPENDICES
Appendix Title
A Field Explorations
B Laboratory Testing
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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1.0 INTRODUCTION
This report presents the results of our field investigations and provides geotechnical engineering
conclusions and recommendations for design and construction of the Howard Street and Sims Way
Improvements project in Port Townsend, Washington. The purpose of this study was to complete
subsurface explorations within the project corridor in order to characterize soil and groundwater
conditions and to develop geotechnical conclusions and recommendations for design and construction of
the proposed improvements.
The general project location is shown on the Vicinity Map (Figure 1). The Site and Exploration
Plans (Figures 2a and 2b) show some of the surrounding features and the approximate locations of the
explorations completed for this study. Appendix A presents a description of the field exploration program
and summary logs of conditions observed in the explorations completed for this study. Appendix B
presents a description and the results of the laboratory testing program.
This report has been prepared based on our discussions with representatives of the City of Port
Townsend (City), WHPacific (project civil engineer), and Transpo Group (project traffic consultant); base
maps of the project area provided by WHPacific; our review of readily available subsurface information
in the project area, the results of the explorations completed for this project; our familiarity with geologic
conditions within the vicinity of the project area; and our experience on similar projects.
1.1 PROJECT DESCRIPTION
We understand that the project includes the extension of Howard Street between the existing
intersection of Howard Street and East Park Avenue towards Discovery Road. The proposed Howard
Street, which will be located west of the existing Howard Street right-of-way (ROW), will include a
single travel lane in each direction, bike lanes, and on-street parking. A roundabout will be constructed at
the intersection of the new Howard Street and Discovery Road. A gravel multi-use trail will be
constructed within the existing Howard Street ROW.
The Sims Way portion of the project, which includes the existing Howard Street north of Sims
Way, consists of the construction of two roundabouts: one at the intersection of Sims Way and Howard
Street, and one at the intersection of Sims Way and Thomas Street. Between the two roundabouts, Sims
Street will be developed into a boulevard. The roadway will include a single roadway and bike lane in
each direction. A new landscaping area and sidewalk will be situated on each side. A center median will
separate the two lanes of traffic. Isolated left turn lanes will be installed at selected locations.
Improvements along Howard Street, between the proposed new roundabout to just south of the
intersection of East Park Avenue, include a new center median and sidewalks.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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We understand that stormwater runoff from the project will be treated with rain gardens
interspersed within the project area. Stormwater detention facilities are being considered along Logan
Road and in the empty field located southwest of the intersection of Sims Way and Howard Street.
1.2 SCOPE OF SERVICES
Landau Associates was subcontracted by WHPacific to provide geotechnical services to support
the project. Our geotechnical services were provided in accordance with terms and conditions of the
Subcontract Agreement between WHPacific and Landau Associates and our Proposal for Geotechnical
Services dated May 2, 2008.
To support the proposed project, we provided the following specific services:
Compiled and reviewed readily available geotechnical and geologic information in the project
vicinity.
Completed seven geotechnical borings (B-1 through B-7) to depths of between about 15½
and 31½ ft below existing site grades (BGS) to characterize soil and groundwater conditions
along the Sims Way portion of the project and at each of the two studied storm pond
locations.
Completed ten geotechnical test pits (TP-1 through TP-10) to depths of between about 5 and
8 ft below existing site grades (BGS) to characterize soil and groundwater conditions along
the Howard Street portion of the project.
Logged each soil unit observed in the exploratory borings and test pits and recorded pertinent
information, including soil sample depths, stratigraphy, soil engineering characteristics, and
groundwater occurrence.
Completed geotechnical laboratory testing consisting of natural moisture content
determinations, grain size analyses, and modified Proctor testing on selected samples
obtained from the explorations. The results of the laboratory analyses are included in
Appendix B.
Collected bulk representative subgrade soil at selected locations. The bulk representative
subgrade soil samples were submitted to Analytical Resources, Inc. of Tukwila, Washington
for the purpose of completing California Bearing Ratio tests. The results of the laboratory
analyses are included in Appendix B.
Completed geotechnical engineering analyses and developed geotechnical engineering
conclusions and recommendations in accordance with the WSDOT Standard Specifications
for Road, Bridge, and Municipal Construction (WSDOT 2008b) for design and construction
of the proposed improvements.
Prepared and submitted this written report summarizing our findings, conclusions, and
recommendations for the project. This report includes:
-a site plan showing the approximate locations of the explorations completed for this
investigation
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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-descriptive summary logs of the conditions encountered in the explorations completed for
this study
-a summary of surface and subsurface conditions observed along the alignment
-recommendations for earthwork including: wet weather construction considerations;
clearing, grubbing and stripping; earthwork requirements; temporary and permanent
slopes; subgrade preparation; and structural fill and compaction criteria
-recommendations for installation of new utilities including: construction dewatering,
trench excavation and support, pipe foundation and support, pipe bedding and initial
backfill, and trench backfill and compaction criteria
-an evaluation of appropriate retaining wall types for the cut retaining wall planned for the
northwest and southwest corner of Sims Way and Thomas Street
-geotechnical design parameters for gravity retaining walls including: foundation subgrade
preparation, allowable bearing pressure and settlement, wall design software input
parameters (used to calculate static and dynamic lateral earth pressures and sliding
resistance), surcharge pressures, wall backfill and compaction requirements, and retaining
wall drainage considerations
-geotechnical design parameters for soldier pile walls including: lateral earth pressures,
soldier pile design, facing design, and wall drainage considerations
-recommendations for luminaire foundations in accordance with WSDOT design
methodology
-an assessment of the feasibility of stormwater infiltration and preliminary design
infiltration rates
-recommendations for pavement overlays and new pavement sections in accordance with
AASHTO 1993 design method
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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2.0 EXISTING SITE CONDITIONS
This section provides a discussion of the general surface and subsurface conditions observed
along the project corridor at the time of our investigations. Interpretations of the site conditions are based
on the results of our review of available information, site reconnaissance, subsurface explorations, and
laboratory testing.
2.1 SURFACE CONDITIONS
At the time of our field explorations, the portion of Sims Way that is the subject of this report
consists of an asphalt-paved roadway with a single travel lane in each direction. A center turn lane is
located between Howard Street and Cliff Street. A left-turn pocket is located onto southbound Cliff
Street from eastbound Sims Way. Left-turn pockets are provided at the intersection of Sims Way and
Thomas Street. Bus pull-out lanes are located at select intervals along Sims Way. The overall ground
slope increases from about elevation 228 ft at the intersection of Howard Street to about elevation 232 ft
at the intersection of McPherson Street. East of McPherson Street, the ground surface elevation decreases
to about elevation 216 ft at Logan Street. Land use along Sims Way is primarily commercial.
Howard Street consists of an asphalt-paved roadway with a single travel lane in each direction. A
left-turn lane is provided onto Sims Way from southbound Howard Street. Howard Street terminates at a
dead end about 350 ft north of the intersection of Howard Street and South Park Avenue. The overall
ground surface elevation along the existing Howard Street increases from about elevation 228 ft at Sims
Way to elevation 248 ft at the dead end. Land use along Howard Street is primarily commercial with
residential development to the north.
From the terminus of Howard Street, a bike trail extends about 750 ft north and then about 250 ft
west to Discovery Road. Small shrubs are located to the west and south of the bike trail while large trees
and shrubs are located to the east of the bike trail. The ground surface elevation increases to about
elevation 264 ft at the terminus of the bike trail at Discovery Road. The property located to the west and
south of the bike trail (future location of Howard Street Extension) is currently a grass-covered field. The
ground surface in the field rises gently to the north.
Large detention facilities are being considered at two locations south of Sims Way. The first
detention facility will be located at the southern edge of a large grass-covered field located at the
southwest corner of Sims Way and Howard Street. The ground surface slopes to the south from Sims
Way, with a ground surface elevation of about 210 ft at the location of boring B-1. The ground surface
elevation drops steeply to the south and southeast of the proposed pond location.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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The second detention facility will be located east of Logan Street, about 550 ft south of Sims
Way. The second detention facility is situated in a relatively level field located behind some residential
structures. Boring B-6, which was advanced at this location, is situated at about elevation 206 ft. A steep
ravine is located to the west of the proposed detention pond. A stream is located at the base of the ravine.
Immediately to the east of boring B-6, the ground surface drops from elevation 206 ft to elevation 142 ft
in a horizontal distance of 160 ft. Large trees and shrubs are located in the ravine.
2.2 GEOLOGIC SETTING
The geologic setting of the project area has been largely influenced by advancing and retreating
glacial ice. During the Pleistocene Epoch (early Quaternary), 2 million to 10,000 years before the present
(ybp), vast continental ice sheets advanced into the Puget Sound region. Evidence indicates that there
were at least six advances of the continental ice into the region during the Pleistocene Epoch.
The latest glacial advance, referred to as the Vashon Stade of the Fraser Glaciation, occurred
between about 22,000 and 13,000 ybp and had the greatest effect on the present-day landscape. As the
continental glacier advanced into Puget Sound, the ice blocked the Strait of Juan de Fuca forming a large
fresh water lake. The lake drained to the south, out through the Black Hills south of Olympia and to the
Pacific Ocean through the ancestral Chehalis River. Fine-grained sediments (silt and clay) from the
glacier and from rivers and streams flowing from the Cascade and Olympic mountains were deposited in
the lake. As the glacier continued to advance, meltwater streams issuing from the glacier laid down
extensive deposits of chiefly sand and gravel outwash (advance outwash), filling the lake and burying
much of the preglacial topography. The glacier advanced over the lake and outwash deposits, scouring
out some areas and depositing glacial till over the surface in other areas. The deposits were highly
consolidated by the weight of the overlying ice, resulting in highly compact soils. As the glacier retreated
(ablated), recessional deposits of sand and gravel outwash, along with ablation deposits of silt, sand and
gravel, were laid down in some areas. Normal erosional and depositional processes further modified the
post-glacial landscape.
Geologic information for the project area was obtained from the Geologic Map of the Port
Townsend South and Part of Port Townsend North 7.5-Minute Quadrangles, Jefferson County,
Washington (Schasse and Slaughter 2005) published by the Washington Division of Geology and Earth
Resources. According to Schasse and Slaughter, subsurface conditions in the project area have been
mapped as glacial till with ablation till at the north end of the project. Although not shown on the above
referenced geologic map, advance outwash generally underlies the glacial till at depth. The mapped soil
units are described, from oldest to youngest, in the following paragraphs.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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Advance outwash predominately consists of clean sand with increasing gravel content higher in
the section. Silt and fine-grained sand are common in portions of the unit. Sorting, cross and horizontal
stratification, and cut and fill structures are distinctive features of outwash. Outwash is transported by
meltwater and deposited in streams and pools emanating from the face of an advancing glacier. This unit
has been glacially overridden, typically exhibits high permeability, and is susceptible to erosion especially
when exposed on steep slopes.
Soil defined as glacial till consists of a dense to very dense, unsorted mixture of boulders,
cobbles, gravel, and sand in a matrix of silt and clay with some lenses of sorted, stratified sand and gravel.
This unit typically exhibits low permeability and high shear strength, characteristics resulting from
compaction by the weight of the overlying glacier.
Ablation till is of similar composition as glacial till, but is less dense. The lower density of the
ablation till results from deposition by or nearby stagnant ice without being fully overridden by the
weight of an active, advancing glacier.
With development of the area, portions of the native soil has either been removed or covered with
fill. Fill across the site is expected to consist of reworked glacial deposits and/or import materials.
2.3 FIELD EXPLORATIONS AND LABORATORY TESTING
Subsurface conditions along the project alignment were explored by advancing and sampling
seven exploratory borings (B-1 through B-7) and ten test pits (TP-1 through TP-10). A detailed
discussion of the field exploration program, together with edited logs of the exploratory borings, is
presented in Appendix A.
The borings were completed with a truck-mounted, hollow-stem auger drill rig between June 26
and June 27, 2008. The exploratory borings were advanced to depths ranging from between 15½ and
31½ ft below the existing ground surface (BGS). The exploratory borings were completed by Holocene
Drilling, Inc. of Fife, Washington under subcontract to Landau Associates.
The test pits were completed with a rubber-tired backhoe supplied and operated by the City of
Port Townsend on June 26, 2008. The test pits were excavated to depths of between 5 and 8 ft BGS. The
location of the exploratory borings and test pits are shown on Figure 2A and 2B of this report.
Geotechnical laboratory testing consisted of natural moisture content determinations, sieve
analysis, modified Proctor density determinations, and California Bearing Ratio (CBR) testing on selected
samples from the borings and test pits. A discussion of the geotechnical laboratory test procedures and
test results are presented in Appendix B of this report.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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2.4 SUBSURFACE SOIL CONDITIONS
Based on the results of the field exploration program and our review of available geologic
information, the proposed roadway improvements are underlain by a sequence of ablation and glacial till.
Advance outwash is located below the glacial till of depth. Portions of the ablation till and glacial till are
overlain by asphalt pavement, topsoil, and/or fill.
2.4.1 SIMS WAY
Boring B-2 was advanced southwest of the intersection of Sims Way and Howard Street at the
location of the future eastern roundabout. At boring location B-2, about 3 ft of crushed-rock, consisting
of medium dense, moist, sandy gravel to gravelly, fine to coarse sand, was encountered. Fill consisting of
loose to medium dense, moist to wet, silty, fine to coarse sand with gravel was encountered below the
crushed rock to a depth of about 12 ft BGS. Glacial till was encountered below the fill throughout the
remaining depth explored and consists of very dense, moist, silty, very gravelly, fine to medium sand.
Borings B-3 through B-5 were advanced through the existing asphalt pavement of Sims Way.
The asphalt pavement section was between 6 and 10½ inches thick at the boring locations. Between 4
and 12 inches of crushed rock, consisting of dense, moist, gravelly to very gravelly, fine to coarse sand
with variable silt content, was encountered below asphalt pavement. Glacial till was encountered below
the crushed rock throughout the remaining depths explored (between about 15½ and 16 ft BGS). Glacial
till consists of medium dense to very dense, moist, gravelly to very gravelly, fine to coarse sand with
variable silt content.
2.4.2 HOWARD STREET
Boring B-7 was advanced within the existing Howard Street south of the intersection of Howard
Street and 6th Street. About 2½ inches of asphalt concrete pavement was encountered in this boring. The
asphalt pavement is underlain by about 6 inches of crushed rock consisting of medium dense, moist, silty,
gravelly, fine to coarse sand. Glacial till, consisting of dense to very dense, moist, silty, gravelly, fine to
coarse sand was encountered beneath the crushed rock and extends to the depth explored (about 15½ ft
BGS).
Test pits TP-2 through TP-5 were advanced along the future alignment of Howard Street.
Between ½ and 1 ft of topsoil was encountered in these explorations. The topsoil was observed to consist
of loose to medium dense, wet, silty, gravelly, fine to coarse sand, with abundant organics. Ablation till
was encountered below the topsoil to depths of between and 3 and 4⅓ ft BGS. Ablation till was observed
to consist of loose to medium dense, moist to wet, silty, fine to coarse sand with variable gravel content.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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Glacial till was encountered below the ablation till throughout the remaining depths explored (between 6
and 7 ft BGS). Glacial till was observed to consist of dense to very dense, moist to wet, silty, fine to
coarse sand, with variable gravel content.
2.4.3 EXISTING HOWARD STREET ROW – MULTI-USE TRAIL AND RAIN GARDENS
Test pits TP-7 through TP-10 were advanced adjacent to the proposed multi-use trail and rain
gardens planned for within the existing Howard Street ROW. Test pit TP-1 was advanced east of the
future Howard Street/Discovery Road roundabout. At these locations, between 3 to and 8 inches of
topsoil is present. Topsoil was observed to consist of loose to medium dense, silty, gravelly, sand with
abundant organics. Ablation till was encountered below the topsoil to depths of between 2½ and 4¼ ft
BGS. Ablation till encountered in the explorations consists of loose to medium dense, moist to wet, silty,
fine to coarse sand with variable gravel content. Glacial till was encountered below the ablation till in
each of the test pits completed in this portion of the project area. Glacial till was observed to consist of
dense to very dense, moist to wet, silty, fine to coarse sand with variable gravel content.
2.4.4 PROPOSED STORM POND
Test pit TP-6 was advanced at the location of the proposed storm pond northwest of the future
intersection of Howard Street and 6th Street. At this location about 15 inches of topsoil was encountered.
The topsoil consists of loose to medium dense, wet, silty, gravelly, fine to coarse sand with abundant
organics. Ablation till was encountered to a depth of about 6 ft BGS. Ablation till encountered at this
location consists of loose, moist, very silty, fine to medium sand with gravel. Glacial till was encountered
throughout the remaining depth explored (about 8 ft BGS). The glacial till consists of dense, moist, silty,
fine to coarse sand with gravel.
2.4.5 DETENTION FACILITY – SOUTHWEST OF SIMS WAY/HOWARD STREET INTERSECTION
Boring B-1 was advanced at the location of the proposed stormwater detention facility located
southwest of the intersection of Sims Way and Howard Street. At this location, about 3 ft of topsoil was
encountered. The topsoil was observed to consist of very loose, wet, gravelly, silty, fine to coarse sand
with roots. Ablation till was encountered below the topsoil to a depth of about 5½ ft BGS. Ablation till
was observed to consist of very loose to loose, wet, fine to medium sand with silt to trace silt. Glacial till
was encountered throughout the remaining depth explored (about 30½ ft BGS) and consists of very dense,
moist, silty, gravelly, fine to coarse sand.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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2.4.6 DETENTION FACILITY – LOGAN STREET LOCATION
Boring B-6 was advanced near the proposed location of the detention facility adjacent to Logan
Street. About 3½ ft of topsoil, consisting of medium dense, wet, gravelly, silty, fine to coarse sand with
numerous roots, is present. The topsoil is underlain by about 1 ft of ablation till consisting of medium
dense, damp, gravelly, fine to coarse sand with silt. Glacial till was encountered between 4½ and 22½ ft
BGS. Glacial till was observed to consist of very dense, moist, silty, gravelly, fine to coarse sand.
Advance outwash was encountered below the glacial till throughout the remaining depth explored (about
31½ ft BGS). Advance outwash consists of very dense, damp to moist, fine to coarse sand with silt and
variable gravel content.
2.5 GROUNDWATER
Groundwater was not encountered at the time of exploration (late-June 2008) at any of the
explorations completed for this study; however, the exploratory borings and test pits were left open for
only a short period of time and very slow groundwater seepage may not have been evident prior to
backfilling the holes. Given the relatively low permeability of the glacial till, a thin, discontinuous,
seasonal perched groundwater table may develop on the glacial till surface. Groundwater is likely present
in the advance outwash deposits at elevations below the maximum depth of the borings. At the proposed
location of the detention facility adjacent to Logan Street, the site groundwater table is likely above the
elevation of the existing creek to the east (i.e. above about elevation 140 ft).
It should be noted that the groundwater conditions reported on the summary logs are for the
specific locations and dates indicated, and therefore may not necessarily be indicative of other locations
and/or times. Furthermore, it is anticipated that groundwater conditions will vary depending on local
subsurface conditions, the weather and other factors. Groundwater levels in the project area are expected
to fluctuate seasonally, with maximum groundwater levels generally occurring during the winter and early
spring months.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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3.0 CONCLUSIONS AND RECOMMENDATIONS
Based on conditions observed in the explorations and results of our engineering evaluation,
construction of the proposed Sims Way/Howard Street Improvements project is considered to be feasible
using conventional means and methods. Geotechnical conclusions and recommendations are presented in
the following sections for earthwork including road subgrade preparation, underground utilities, retaining
walls, luminaire foundations, stormwater infiltration, and pavement design.
3.1 EARTHWORK
Earthwork to accommodate the proposed roadway widening is expected to consist of clearing,
grubbing, and stripping of areas where the roadway will be widened, fills and cuts to accommodate the
widened roadway, and subgrade preparation for new pavement.
3.1.1 WET WEATHER CONSIDERATIONS
Earthwork-related construction will be influenced by weather conditions. Most of the existing
near-surface soil along the roadway alignment consists of ablation and glacial till which contain a
significant amount of fine sand and silt, making the existing near-surface soil highly sensitive to moisture.
Site grading activities using moisture-sensitive soil should normally occur during the relatively warmer
and drier period between about mid-summer to early fall. Completing these activities outside of this
normal construction window could lead to a significant increase in construction costs due to weather-
related delays, repair of disturbed areas, and the increased use of “all-weather” import fill materials.
Because of the moisture sensitivity, unprotected site soil, in either a compacted or uncompacted
state, will degrade quickly to a slurry-like consistency in the presence of water and construction traffic. If
subgrade or fill soil becomes loosened or disturbed, additional excavation to expose undisturbed soil and
replacement with properly compacted structural fill will be required. For wet weather construction, the
contractor may reduce the potential for disturbance of subgrades by the following:
Protecting exposed subgrades from disturbance by construction activities by constructing
gravel working mats
Using a trackhoe with a smooth-bladed bucket to limit disturbance of the subgrade during
excavation
Suspending earthwork and other construction activities that may damage subgrades during
rainy days
Limiting and/or prohibiting construction traffic over unprotected soil
Providing designated haul roads for construction equipment
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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Sloping excavated surfaces to promote runoff
Sealing the exposed surface by rolling with a smooth drum compactor or rubber-tire roller at
the end of each working day and removing wet surface soil prior to commencing filling each
day.
3.1.2 DEMOLITION AND CLEARING, GRUBBING AND STRIPPING
Clearing and grubbing should be in accordance with the requirements in Section 2-01 of the 2008
Standard Specifications for Roadway, Bridge, and Municipal Construction (WSDOT Standard
Specifications) by the Washington State Department of Transportation (WSDOT 2008b). Material
generated during clearing and grubbing should be properly disposed of at an approved offsite location.
Topsoil, and/or other organic-rich soil located within areas to be improved should be stripped to expose
the underlying inorganic soil. Based on conditions observed in the explorations completed in the vicinity
of the new Howard Street alignment, stripping depths to remove organic-rich soil may be up to 15 inches.
Stripped material is not considered suitable for use as fill beneath pavement or sidewalk areas. Stripped
material should either be wasted offsite at an approved location, or stockpiled for later use as topsoil.
The removal of existing improvements (e.g., existing pavement sections) should be in accordance
with the requirements of Section 2-02 of the 2008 WSDOT Standard Specifications. Existing asphalt
pavement that is removed to accommodate the proposed improvements may be pulverized, stockpiled,
and recycled for use per the requirements in Section 9-03.21(2) of the 2008 WSDOT Standard
Specifications. Disposal of the asphalt rubble at an approved offsite location is also a viable alternative.
Utilities that will be abandoned that are less than 3 ft deep should be removed and disposed of
off-site. Deeper lines may be left in place but should be grouted full with controlled density fill (CDF) to
reduce the potential for differential settlement resulting from potential collapsed pipes or erosion. CDF
should meet the requirements in Section 2-09.3(1)E of the 2008 WSDOT Standard Specifications.
All incidental excavations associated with clearing and grubbing should be backfilled in
accordance with the recommendations in Section 3.1.6 of this report.
3.1.3 TEMPORARY AND PERMANENT SLOPES
In order to accommodate construction of the new retaining walls planned for the intersection of
Sims Way and Thomas Street, temporary excavations may be required. Based on the soil conditions
observed in our explorations, we anticipate that temporary excavations will generally encounter ablation
till and glacial till. Temporary excavations into ablation till should be sloped no steeper than 1½H:1V
(horizontal to vertical). Temporary excavations into glacial till should be sloped no steeper than 1H:1V.
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Temporary excavation slopes should be protected by covering with plastic sheets, straw, or other
means to prevent erosion. Also, temporary excavation slopes should be the sole responsibility of the
contractor. All local, state, and federal safety codes should be followed. The contractor should
implement measures to prevent surface water runoff from entering excavations. All temporary excavation
slopes should be monitored by the contractor during construction for any evidence of instability. If
instability is detected, the contractor should flatten the temporary excavation slopes or install temporary
shoring. If groundwater or groundwater seepage is present, flatter excavation slopes should be expected.
In areas where sufficient space is available for permanent slopes, the permanent cut and fill slopes
should be sloped no steeper than 2H:1V. Permanent slopes should be hydroseeded as soon as practical to
prevent erosion or covered with either mulch or erosion control netting/blankets, and bonded fiber matrix.
3.1.4 SUBGRADE PREPARATION
Following clearing, stripping, and any required overexcavation to remove any unsuitable
foundation soil, and before placement of any structural fill, the upper 9 to 12 inches of exposed soil
should be scarified, moisture-conditioned, and compacted as described in Section 3.1.6 of this report.
Overexcavation of unsuitable foundation soil should be in accordance with Section 2-03.3(14)E of the
2008 WSDOT Standard Specifications. The prepared subgrade should be proof-rolled with a loaded
dump truck, large self-propelled vibrating roller, or equivalent piece of equipment in the presence of a
qualified geotechnical or civil engineer to check for the presence of soft, loose, and/or disturbed areas. If
any soft, loose, and/or disturbed areas are revealed during proof-rolling, these areas should either be
moisture conditioned and recompacted to the required density, or removed and replaced with Select
Borrow meeting the requirements in Section 9-03.14(2) of the 2008 WSDOT Standard Specifications,
and compacted to the required density.
3.1.5 STRUCTURAL FILL
Structural fill is defined as material needed to establish planned subgrade elevations within the
roadway corridor. Recommendations for fill material for other applications are provided later in this
report.
The suitability of excavated soil or imported soil for use as structural fill will depend on the
gradation and moisture content of the soil when it is placed. As the amount of fines increases, the soil
becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes
more difficult to achieve. Soil containing more than about 5 percent fines cannot consistently be
compacted to a dense, non-yielding condition when the water content is greater than about 2 to 3 percent
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above optimum moisture content. Optimum moisture content is the moisture content at which the
greatest compacted dry density can be achieved.
The near-surface soil encountered within the roadway corridor consists predominately of ablation
and glacial till. Localized areas of fill likely consisting of reworked ablation and/or glacial till are also
present within the roadway corridor. The ablation and glacial till at the site has a relatively high fines
content, which indicates that it is highly moisture sensitive. Based on the results of our field investigation
and laboratory testing program, the ablation and glacial till have natural moisture contents of between 6
and 17 percent, with an average moisture content of about 9 percent.
Modified Proctor (natural soil moisture content and moisture-density relationship tests) were
conducted on four near-surface soil samples. The Modified Proctor testing was completed in general
accordance with the ASTM D1557 test procedure. The purpose of the Modified Proctor testing was to
determine the level of moisture conditioning required to use the near-surface granular soil for structural
fill. A summary of the test results is provided in the table below. The optimum moisture content of the
tested samples determined from the Modified Proctor testing ranged from 4 to 8 percent.
MODIFIED PROCTOR TEST RESULTS SUMMARY
Sample Designation Sample Composition Unified Soil Classification
Maximum
Dry Density (pcf) (a)
Optimum
Moisture
Content (percent) (a)
Natural
Moisture
Content (percent)
B-3, S-0 Very gravelly, fine to
coarse SAND with silt SP-SM 138 5 4
B-5, S-0 Gravelly, silty, fine to
coarse SAND SM 137 7 8
TP-2, S-1 Gravelly, silty, fine to
coarse SAND SM 134 8 8
TP-5, S-1 Silty, fine to coarse
SAND with gravel SM 134 7 8
(a) Maximum dry density and optimum moisture content has been corrected for oversize portion.
Based on its present natural moisture content, the ablation and glacial till is near its optimum
moisture content for compaction and could be suitable for use as structural fill provided suitable weather
conditions prevail; however, some moisture conditioning (wetting or drying) will be required. The
moisture content would be expected to increase during wetter months to percentages possibly well above
optimum. Therefore, we recommend that the use of the onsite ablation and glacial till for use as structural
fill be limited to extended periods of dry weather in the summer and early fall months (about July through
mid-October) where the moisture can be more easily controlled. If the onsite soil is utilized for use as
structural fill, the contractor will need to properly segregate the non-suitable material from the suitable
material.
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If the onsite soil cannot be utilized as fill, or if additional fill material is needed to establish
planned road subgrade elevations, import fill will be necessary. Import fill should meet the requirements
for Select Borrow in Section 9-03.14(2) of the 2008 WSDOT Standard Specifications. If wet weather
construction is anticipated, the amount of fines (material passing a U.S. No. 200 sieve) should not exceed
5 percent, by dry weight, based on a wet sieve analysis of that portion passing the ¾-inch sieve.
During periods of wet weather, it may be impractical to moisture condition subgrades composed
primarily of ablation and glacial till. Additional overexcavation of the subgrade, the use of geotextile to
provide separation of the subgrade soil and import structural fill, and/or the use of soil additives (i.e. lime,
cement, kiln dust) may be required to perform earthwork during wet weather. If wet weather construction
is anticipated, a qualified geotechnical engineer should evaluate wet weather construction requirements.
3.1.6 BACKFILL AND COMPACTION REQUIREMENTS
Structural fill should be placed and compacted in accordance with Section 2-03.3(14)C, Method
C of the 2008 WSDOT Standard Specifications. Compaction and moisture control tests should be done
in accordance with Section 2-03.3(14)D of the 2008 WSDOT Standard Specifications. The maximum
dry density and optimum moisture content may also be determined by the ASTM D1557 test procedure.
3.2 UTILITY CONSTRUCTION
The following sections provide geotechnical recommendations for design and construction of
new site utilities. Geotechnical recommendations are included for installation of new site utilities
including construction dewatering, trench excavation and retention, pipe foundation support, pipe bedding
and initial backfill, trench backfill and compaction criteria, and anticipated loads on pipes. The specific
trench depths were unknown at the time this report was prepared, however, the anticipated trench depth
are typically not expected to be more than about 10 ft BGS.
3.2.1 CONSTRUCTION DEWATERING
Although groundwater was not observed in any of the geotechnical explorations completed for
this study, localized zones of shallow, perched groundwater may be encountered above relatively dense
glacial till, especially during the wet portion of the year. If shallow groundwater is encountered during
trench excavation, we expect that open sump pumping will be adequate to control groundwater flow into
the trench, provided the trench walls remain stable. If groundwater or groundwater seepage is present, and
flow into the trench is not properly controlled, the soil composing the trench walls may be prone to
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caving, channeling, and running. Trench widths may be substantially wider than under dewatered
conditions.
3.2.2 TRENCHING AND EXCAVATION SUPPORT
It is anticipated that excavation for the proposed utilities will be in loose to medium dense fill,
loose to medium dense ablation till, and/or medium dense to very dense glacial till. A heavy-duty,
hydraulic excavator with sufficient reach should be able to excavate the proposed trenches to the planned
depths. Cobble and boulder are common in ablation and glacial till; consequently, the contractor should
be prepared to handle and dispose of such oversized material. Upon reaching the trench bottom, we
recommend that a “smooth-bladed” bucket be used to clean the trench bottom of loose and/or disturbed
soil. The final trench bottom should be firm and free of loose and disturbed soil.
Trench excavation should conform to the requirements of Section 7-08.3(1)A of the 2008
WSDOT Standard Specifications. Actual trench configurations and maintenance of safe working
conditions, including temporary excavation stability, should be the responsibility of the contractor. All
applicable local, state, and federal safety codes should be followed. Temporary excavations in excess of
4 ft should either be shored or sloped in accordance with Safety Standards for Construction Work, Part N,
located in Chapter 296-155 of the Washington Administrative Code (WAC). In the absence of
groundwater seepage, fill and ablation till encountered within the trench zone would be classified as a
Type C soil per Chapter 296-155 of the WAC. Glacial till would classify as a Type B soil per Chapter
296-155 of the WAC. The prescriptive maximum allowable excavation slope for Type C soils is 1½H:1V
(horizontal to vertical). The prescriptive maximum excavation slope for Type B soils is 1H:1V. If
groundwater seepage is present, flatter slopes, temporary shoring, and/or dewatering may be required.
Trench boxes should provide adequate support for shallow excavations, provided the trench is
properly dewatered and settlement-sensitive structures and utilities are not situated immediately adjacent
to the excavation. Trench boxes should meet the requirements in Safety Standards for Construction
Work, Part N, located in Chapter 296-155 of the WAC.
Where a trench box is used to support excavations, one or both sides of the trench may cave
against the box, especially if granular soil is present. Undisturbed glacial till is usually not susceptible to
caving. The caving may extend out on either side of the trench for a distance approximately equal to the
depth of the granular soil. Caving can be reduced by routing stormwater away from the excavation and
limiting vehicular traffic or vibrations next to the trench. Additional bracing or sheeting may be required
where the near edge of the trench will be closer than 1.5 times the trench depth to settlement sensitive
utilities or structures. When the trench box is moved, precautions should be taken to minimize
disturbance of the pipe, underlying bedding materials, and surrounding soil.
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If bracing is needed to support the trench walls, the temporary bracing system should be designed
by a structural engineer licensed in the State of Washington. Temporary shoring typically consists of
steel plates with internal bracing. Temporary shoring may also be used in conjunction with sloped
excavations. If sloped excavations are used in conjunction with trench boxes, the slopes should be sloped
no steeper than 1½H:1V. Surcharge loads on trench support systems due to construction equipment,
stockpiled material, and vehicle traffic should be included in the design. A properly designed shoring
system will have the benefit of reducing potential settlements of adjacent facilities (e.g. utilities and
structures). The temporary shoring design should be submitted to the City for review prior to
construction.
3.2.3 PIPE FOUNDATION SUPPORT
Based on conditions observed at the exploration locations, soil at planned trench depths are
anticipated to primarily consist of medium dense to very dense glacial till. Glacial till will provide
adequate foundation support for the pipeline, provided that it remains in a relatively undisturbed condition
and that the trench is properly dewatered.
The soil at the trench bottom can be easily disturbed by construction activities, and in a disturbed
condition will generally provide poor foundation support for the pipeline. If the trench bottom becomes
disturbed due to excavation and/or foot traffic during laying of the pipe, the trench bottom may need to be
overexcavated to expose undisturbed foundation soil. Removal and replacement of unsuitable foundation
material should be in accordance with Section 7-08.3(1)A of the 2008 WSDOT Standard Specifications.
The overexcavation should be backfilled with suitable foundation material to provide a firm trench
bottom. Foundation material should meet the requirements for Class B Foundation Material in Section 9-
03.12(1)B of the 2008 WSDOT Standard Specifications. Pipe foundation material should be placed and
compacted in accordance with the recommendations provided in Section 3.1.6 of this report.
Alternatively, if the trench bottom is relatively free of water, Controlled Density Fill (CDF) could be used
as foundation material. CDF should meet the requirements in Section 2-09.3(1)E of the 2008 WSDOT
Standard Specifications.
3.2.4 PIPE BEDDING AND INITIAL BACKFILL
To provide uniform support of buried utility pipes, the pipe should be bedded in accordance with
Section 7-08.3(1)C of the 2008 WSDOT Standard Specifications. The bedding material should extend 6
inches below the invert of the pipe. Bedding material for buried utility pipes should consist of Gravel
Backfill for Pipe Zone Bedding meeting the requirements Section 9-03.12(3) of the 2008 WSDOT
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Standard Specifications. For rigid pipes (concrete and ductile iron), the bedding material should extend
above the pipe bottom a distance of at least 15 percent of the pipe outside diameter. For flexible pipes
(PVC, HDPE, etc.), the bedding material should extend at least 6 inches above the crown of the pipe. For
metal pipe, the bedding material should extend to at least the spring line of the pipe.
Pipe zone backfill for rigid and metal pipes should meet the requirements of Section 7-08.3(3) of
the 2008 WSDOT Standard Specifications. Soil excavated from the pipe zone would be suitable for use
for pipe zone backfill for rigid and metal pipes provided that it is near its optimum moisture content and
cobble or boulder (i.e. materials with particle size greater than 3 inches) are removed from the soil and the
soil can be adequately compacted. If additional material is needed for pipe zone backfill or if wet weather
construction is anticipated, Gravel Backfill for Pipe Zone Bedding meeting the requirements Section 9-
03.12(3) of the 2008 WSDOT Standard Specifications should be used. The amount of fines (material
passing a U.S. No. 200 sieve) in the Gravel Backfill for Pipe Zone Bedding should not exceed 5 percent,
by dry weight, based on a wet sieve analysis of that portion passing the ¾-inch sieve.
Pipe bedding material and pipe zone backfill should be brought up evenly around the pipe in
relatively horizontal lifts not exceeding 6 inches, and worked under the haunches of the pipe by slicing
with a shovel, vibration, or other approved procedures. Pipe zone backfill should extend 6 inches above
the crown of the pipe. Pipe bedding and pipe zone backfill should be compacted to at least 90 percent of
the maximum dry density determined in accordance with Section 2-03.3(14)D of the 2008 WSDOT
Standard Specifications. The maximum dry density may also be determined by the ASTM D1557 test
procedure.
3.2.5 TRENCH BACKFILL AND COMPACTION CRITERIA
As discussed in Section 3.1.5, the onsite granular soil may be used for trench backfill, provided it
is properly moisture conditioned and compacted to the required density. If additional material is required
for trench backfill, then imported material meeting the requirements detailed in Section 3.1.5 of this
report should be used for trench backfill.
Backfilling of trenches should be in accordance with the requirements of Section 7-08.3(3) of the
2008 WSDOT Standard Specifications. Trench backfill should be placed in 6-inch layers and compacted
to a relative density of at least 95 percent of the maximum dry density. Compaction testing should be in
accordance with the requirements of Section 2-03.3(14)D of the 2008 WSDOT Standard Specifications.
Alternatively, the maximum dry density may be determined by using the ASTM test method D 1557.
Flooding and/or jetting of backfill should not be used as a means to consolidate or compact trench
backfill. Hand-operated compaction equipment, or other approved methods, should be used to compact
the first 18 inches of trench backfill above the pipe.
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3.3 RETAINING WALLS
We understand that cut retaining walls will be necessary at the northwest and southwest corner of
the intersection of Sims Way and Thomas Street. Gravity walls could be utilized to support relatively
minor (i.e. less than about 5 ft tall) cuts provided sufficient space is present to accommodate any
temporary excavation cuts. For gravity walls greater than about 5 ft tall, mechanically stabilized earth
(MSE) reinforcing elements may be required, necessitating larger cuts. If an insufficient amount of room
is available to construct gravity walls or if the walls are greater then about 5 ft tall, soldier pile walls may
be needed. Recommendations for temporary construction slopes to accommodate retaining wall
construction are provided in Section 3.1.3 of this report.
3.3.1 GRAVITY BLOCK WALLS
Several types of gravity-type retaining structures, such as rock-filled gabion baskets, crib walls,
and concrete block walls (Kelly Block™, Ultra Block™) would be appropriate for use at the intersection
of Sims Way and Thomas Street. Sliding and overturning of gravity walls is resisted by the dead weight
of the wall elements (i.e. rock-filled wire baskets, soil-filled crib baskets, and concrete blocks), by friction
along the base of the bottom row of wall elements, and the friction between individual baskets. The base-
to-height ratio of gravity block walls is typically between 1:1 and 1:2.
The principal advantages of gravity wall systems include their relatively low cost when compared
to conventional concrete walls, their ability to accommodate differential settlement without loss of
structural integrity, and the permeability inherent in the structure, allowing both free drainage and earth
retention. A disadvantage of gravity wall systems that support cuts is that they typically require a
relatively large excavation area to accommodate the temporary back-cut for wall construction when the
wall is high enough to require reinforcing elements.
3.3.1.1 Gravity Wall Subgrade Preparation
Based on the results of our explorations and the site topography, the gravity block retaining walls
will likely bear on loose to medium dense ablation till or on medium dense to very dense glacial till. It is
anticipated that ablation and glacial till will provide suitable foundation support, provided it is properly
prepared as recommended herein. Prior to the placement of the first row of blocks, the subgrade soil
should be prepared in accordance with the recommendations contained in Section 3.1.4 of this report.
To facilitate placing of the blocks and protecting the subgrade from disturbance during wall
construction, we recommend that a 6-inch layer of crushed surfacing top course be placed over the
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foundation subgrade. The crushed surfacing material should be compacted in accordance with the
recommendations contained in Section 3.1.6 of this report to produce a dense, unyielding subgrade.
Crushed surfacing material should meet the requirements in Section 9-03.9(3) of the 2008 WSDOT
Standard Specifications. Crushed surfacing should be compacted in accordance with the
recommendations contained in Section 3.1.6 of this report.
3.3.1.2 Gravity Wall Bearing Capacity and Settlement
For a properly prepared foundation subgrade, as recommended above, a maximum allowable soil
bearing pressure of 3,000 pounds per square ft (psf) should be used to proportion the footings for the
retaining walls. The allowable bearing capacity includes a factor of safety of at least 3 applied to the
ultimate bearing capacity and assumes a wall embedment depth of at least 1½ ft.
Settlement of shallow foundations depends on the foundation size and bearing pressure, as well as
the strength and compressibility characteristics of the underlying bearing soil. Assuming the foundation
subgrade has been prepared as recommended above, we estimate that the settlement of the retaining wall
footing will be less than 1 inch. Differential settlement between two points spaced 100 ft away along the
length of the wall will be ½ inch or less. Distortion due to differential settlement along the length of the
wall should be less than 1/300 (ft/ft). Most of the settlement will occur during construction. Post-
construction settlements should be negligible.
3.3.1.3 Wall Design Parameters
The following table provides recommended soil parameters for use in design of modular block
retaining walls.
RECOMMENDED GRAVITY WALL SOIL DESIGN PARAMETERS
Soil Properties
Wall
Backfill
Retained
Soil
Foundation Soil
Unit Weight (pcf) 135 135 135
Friction Angle (degrees) 36 36 36
Cohesion (psf)0 0 0
Ultimate Sliding Resistance Coefficient N/A N/A 0.55
At a minimum, a vertical surcharge load of 250 pounds per square ft (psf) should be included in
analysis of internal stability to simulate typical vehicular traffic loading above the wall (if any). Where
large surcharge loads, such as heavy trucks, a crane, or other construction equipment are anticipated in
close proximity to the retaining walls, the walls should be designed to accommodate the additional lateral
pressures resulting from the surcharge load.
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Dynamic lateral earth pressures from a seismic event with a 10 percent probability of exceedance
in a 50-year period (1-in-475 year event) should be included in the design of all cantilevered soldier pile
walls. For the 1-in-475 year event, a peak horizontal ground acceleration of 31 percent of gravity (0.31g)
is appropriate (USGS 2007). The peak horizontal ground acceleration should be converted to the
maximum wall acceleration coefficient at the centroid of the wall mass, Am, by the following relationship
(AASHTO 2002):
Am = [A*(1.45-A)]
MSE wall systems should be designed for a minimum factor of safety of 1.5 against sliding and
reinforcing element pullout, and 2.0 against overturning for AASHTO Load Group I. For AASHTO
Load Group VII, a minimum factor of safety of 1.1 against sliding and 1.5 against overturning should be
used for design.
3.3.1.4 Wall Backfill and Drainage Considerations
Free-draining sand and gravel material, meeting the requirements for Gravel Backfill for Walls,
in Section 9-03.12(2) of the 2008 WSDOT Standard Specifications, should be used as retaining wall
backfill. Backfill located greater than 3 ft of the wall elements should be compacted in accordance with
the recommendations contained in Section 3.1.6 of this report. To avoid overstressing of the wall during
placement and compaction, backfill placed within 3 ft of the wall elements should be compacted to
between 90 and 92 percent of the maximum dry density as determined by Section 2-03.3(14)D of the
2008 WSDOT Standard Specifications or by the ASTM D1557 test procedure.
Underdrain pipe for gravity walls should be 6 inches in diameter and conform to Section 9-05.2
of the 2008 WSDOT Standard Specifications. The pipe should be placed with the perforations
downward. The pipe should be placed in a minimum 12-inch thick envelope of gravel meeting the
requirements for Gravel Backfill for Drains in Section 9-03.12(4) of the 2008 WSDOT Standard
Specifications. The drain gravel should completely surround the perforated drainpipe and be completely
surrounded by a non-woven geotextile material with a minimum 12-inch overlap. The geotextile should
meet the requirements for Moderate Survivability in Table 1 and for Class B in Table 2 of Section 9-33 of
the 2008 WSDOT Standard Specifications. The top of the perforated pipe should be no higher than the
top of the adjacent footing. The drain line should discharge into the storm drainage system, or an
approved location.
To reduce the possibility of water ponding and infiltrating into the subsurface behind retaining
walls, the adjacent ground surface behind the wall should be sloped to promote runoff away from the top
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of the wall. Alternatively, a line brow ditch could be constructed along the top of the wall to collect
surface water runoff and route it to the storm drain system.
3.3.2 SOLDIER PILE WALLS
Soldier pile walls are cantilevered structures that generally consist of steel H piles or wide flange
sections for vertical elements placed in predrilled, concrete-filled holes. Lagging, consisting of timber or
concrete elements or precast concrete panels are typically used to span between vertical elements and
provide support of the soil. A façade may be placed over the lagging for aesthetic purposes.
3.3.2.1 Lateral Earth Pressures
The soldier pile wall must be designed to resist active lateral earth pressures. The use of active
lateral earth pressures assumes that sufficient deformation (0.1 to 0.2 percent of the wall height) of the
soil behind the wall could occur to develop an active earth pressure. This lateral deformation is likely to
be accompanied by some vertical settlement, which could be up to about 0.05 percent of the wall height.
The applied active lateral earth pressure can be represented by a triangular pressure distribution as
shown on Figure 3. The active lateral earth pressures would act over the soldier pile spacing in the
portion of the wall above the ground surface and over the soldier pile width where the soldier pile is
completely embedded below the ground surface.
If the retaining wall will be subjected to the influence of surcharge loading within a horizontal
distance equal to or less than the height of the wall, the wall should be designed for the additional
horizontal pressure. It is typical practice to accommodate traffic and construction equipment loading with
a vertical surcharge pressure of 250 psf. Earth stockpiles or other larger surcharge loads should be
addressed by use of a higher surcharge pressure. For walls free to rotate during loading, a uniformly
distributed lateral pressure equal to the active pressure coefficient times the vertical surcharge pressure
should be included, as shown on the lateral earth pressure diagrams of Figure 3.
Dynamic lateral earth pressures from a seismic event with a 10 percent probability of exceedance
in a 50-year period (1-in-475 year event) should be included in the design of all cantilevered soldier pile
walls. A peak horizontal ground acceleration of (0.31g) was assumed in computing the dynamic lateral
earth pressures (USGS 2007). The dynamic lateral earth pressure is presented on Figure 3. The resultant
of the dynamic lateral earth pressure can be assumed to act at a point 0.6H above the base of the wall.
The dynamic lateral pressure should be added to the static lateral earth pressures.
Passive pressure criteria for resistance of lateral loads are also presented on Figure 3. The passive
pressure values have been reduced by a factor of 1.5 to limit the amount of movement to less than 3
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percent of the embedment depth of the wall. The passive pressure shown on Figure 3 should be applied
over three times the width of the soldier pile, or the pile spacing, whichever is less.
3.3.2.2 Soldier Pile Design
Soldier piles typically consist of steel H-piles or wide flange sections set in predrilled holes. The
portion of the hole below the base of the wall should be backfilled with structural concrete (Concrete
Class 4000P) to safely transmit the soldier pile loads into the surrounding native soils (WSDOT 2008a).
CDF should be used to fill the holes above the base of the wall. CDF should meet the requirements of
Section 2-09.3(1)E of the 2008 WSDOT Standard Specification.
Soldier piles are typically installed to twice the exposed wall height. For soldier piles bearing in
dense to very dense glacial till, an allowable tip capacity of 20 kips per square foot (ksf) and an allowable
side capacity of 0.35 ksf may be utilized in design for resisting vertical loads acting on the wall. The
allowable capacities presented above include a factor of safety of at least 3 on the calculated ultimate
capacities. The diameter of the predrilled holes should be utilized in calculating the tip and shaft area.
3.3.2.3 Facing Design
Soil arching between the vertical wall elements should be anticipated in the facing design. The
maximum bending moment, Mmax (kip-ft/ft) in the facing element may be computed using the following
relationship:
Mmax = K*p*L2
Where p = average lateral pressure (including earth and surcharge pressure) in ksf/ft acting on
the section of the facing being considered (ksf/ft)
L = spacing between vertical elements in ft.
K = factor that accounts for type of span and whether soil arching develops
= 0.083 for simple or continuous (i.e. reinforced concrete or shotcrete) span with soil
arching
3.3.2.4 Wall Drainage
Solider pile walls should be provided with proper drainage to prevent the buildup of hydrostatic
pressure. Wall drainage should consist of a geocomposite drainage fabric, such as C-Drain™ 11K
(Contech) J-Drain™ 400 (NW linings and Geotechnical Products), or Amerdrain™ 200 (AWD), placed
behind the lagging. The composite drainage material typically comes in widths of 4 ft. As a minimum, a
4 ft wide strip of drainage composite material should be placed between each soldier pile with the
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geotextile face placed against the soil. If a façade is placed in front of the wall, the drainage material
should be placed between the lagging and the façade with the geotextile face against the lagging. The
drainage composite material should extend for the full height of the wall and connect to weep holes at the
base of the wall or to a drainage collection pipe.
3.4 LUMINAIRE FOUNDATIONS
We understand that new luminaires are planned along the project alignment and that the
luminaires will be designed in accordance with the WSDOT design methodology. Based on the results of
our field exploration, laboratory testing, and engineering analyses, it is our opinion that the proposed new
signal standards and light poles can be supported on drilled shaft foundations. The drilled shafts should
be embedded sufficiently to resist lateral forces and the resulting overturning moments.
Luminaire foundations can be designed utilizing an allowable bearing pressure of 1,500 psf.
According to WSDOT Standard Plan J-28.30-00, luminaire foundations should be 3 ft in diameter and
have a foundation depth of 8 ft. If the luminaire foundation is installed in slopes inclined steeper than
2H:1V (horizontal to vertical), a special foundation design will be required.
3.4.1 LUMINAIRE CONSTRUCTION CONSIDERATIONS
Luminaire foundations shall be constructed in accordance with Section 8-20.3(2) and 8-20.3(4) of
the 2008 WSDOT Standard Specifications. Signal pole foundations should be constructed with a single-
flight auger drill rig. A qualified geotechnical or civil engineer should observe drilled shaft excavation
and concrete placement. This will allow the opportunity to confirm conditions indicated by our
explorations and/or provide corrective recommendations adapted to conditions revealed during
construction.
Standard construction methods for signal standard foundations typically involve drilling a vertical
shaft with a single-flight auger rig, placing a steel reinforcing cage into the hole, and filling the hole with
concrete. Large cobbles and boulders are typically encountered in ablation and glacial till. If this method
is chosen, the single-flight auger should be large enough to handle these large soil particles. Groundwater
seepage may occur at the fill and ablation till/glacial till contact.
Depending on ground conditions, the hole may be cased or uncased. For 3 ft diameter holes, the
soil should have sufficient stand time to allow construction of the foundations without casing, although
loose, near-surface fill or ablation till could be subject to caving, especially of groundwater seepage is
present. If casing is used, it should be pulled as concrete is placed and a sufficient head of concrete
should be maintained inside the casing to prevent caving and sloughing of the hole. Alternatively, the
APPENDIX F
V. Appendicies
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casing could be pulled immediately after the placement of the concrete, provided the hole is topped off
after the casing has been removed.
3.5 PAVEMENT DESIGN
Recommendations for new pavement and pavement overlays are provided in this section of the
report.
3.5.1 RESILIENT MODULUS DESIGN VALUE
The subgrade soil observed along the entire alignment generally consists of silty to very silty, fine
to coarse sand with gravel (ablation and glacial till). Representative samples of the subgrade soil were
submitted to Analytical Resources, Inc. (ARI) for CBR testing (ASTM D1883). The results of the CBR
testing indicated that CBR values with percentages ranging from between 24 and 28 percent are
appropriate for subgrade soil compacted to at least 95 percent of the maximum dry density as determined
by ASTM D1557. For design, we recommend utilizing a design CBR of 25 percent. Using the
relationship given in the WSDOT Pavement Design Guide (WSDOT 2008c), Mr = 2,555 CBR0.64, a CBR
of 25 percent is approximately equivalent to a Mr Value of 20,000 psi.
3.5.2 VEHICULAR LOADING AND DESIGN STRUCTURAL NUMBER
The design ESALs for new pavement and pavement overlays were based on traffic data provided
by the Transpo Group (2008). The data provided by the Transpo Group includes: the daily traffic counts
at selected intersections, the percentage heavy vehicles during the peak hours, traffic directional
distribution, and the anticipated traffic growth rate. The traffic data was collected between June 4, 2008
and June 11, 2008.
According to the Asphalt Institute (1981), the percent truck percentage during the peak hour is
about one-half the daily average truck percentage for urban arterials and between one-half to two-thirds
the daily average truck percentage for rural highways. This relationship was used to convert the peak
hour heavy vehicle percentage to the daily truck traffic percentage. WSDOT requires a 50-year pavement
design life for state highways with over 100,000 ESALs per year. Consequently, a 50-year pavement
design life was used in developing the pavement section for Sims Way and the Sims Way roundabouts. A
pavement design life of 20 years was evaluated Howard Street and the Howard Street/Discovery Road
roundabout. A truck factor of 1.0 was assumed in calculating the design ESALs. A summary of the
traffic data and the design ESALs are summarized in the table below.
APPENDIX F
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SUMMARY OF TRAFFIC DATA AND DESIGN ESALs
Location
Average
2010
Daily
Traffic
Design
Life
(Years)
Directional
Distribution
(%)
Truck
Percentage
(%)
Traffic
Growth
Rate
(%)
Growth
Factor
Design
ESALs
Sims Way 18,830 50 51.5 8 1.2 67.2 1.90x107
Howard Street 5,650 20 50 7 2 24.3 1.75x106
Sims Way/Howard
Street Roundabout 11,410 50 100 8 2 84.6 2.82x107
Sims Way/Thomas
Street Roundabout 10,507 50 100 8 1.6 75.7 2.32x107
Discovery Road/Howard
Street Roundabout 1,930 20 100 7 8.1 46.9 2.31x106
As described in Section 3.5.1 of this report, a subgrade resilient modulus, Mr, of 20,000 psi was
utilized in the pavement design. For Sims Way (including the two Sims Way roundabout), a reliability of
85 percent, a standard deviation of 0.50, an initial serviceability index (ISI) of 4.2 (accounts for facility
being in use during rehabilitation work), and a terminal serviceability index (TSI) of 2.7 was used in
calculating the structural number. For Howard Street and the Howard Street/Discovery Road, a reliability
of 75 percent, a standard deviation of 0.50, an ISI of 4.2, and a TSI of 2.7 was used in calculating the
structural number. The table below summarizes the calculated structural number required for each of the
roadway segments.
REQUIRED STRUCTURAL NUMBER
Location
Design
Life
(Years)
Required
Structural
Number
Sims Way 50 3.90
Howard Street 20 2.40
Sims Way/Howard Street
Roundabout 50 4.16
Sims Way/Thomas Street
Roundabout 50 4.03
Discovery Road/Howard
Street Roundabout 20 2.52
3.5.3 NEW PAVEMENT DESIGN RECOMMENDATIONS
Design sections for new pavement were developed using the American Association of State
Highway and Transportation Officials design procedure (AASHTO 1993), and assume that the pavement
subgrade has been prepared in accordance with the recommendations contained in Section 3.1.4 of this
report. Recommended pavement sections are provided in the following table.
RECOMMENDED PAVEMENT DESIGN SECTIONS
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Location
Design
Life
(years)
Asphalt
Concrete
Pavement
Thickness
(inches)
Crushed
Surfacing
Thickness
(inches)
Sims Way 50 8 6
Howard Street 20 5 4
Sims Way/Howard Street
Roundabout 50 8 6
Sims Way/Thomas Street
Roundabout 50 8 6
Discovery Road/Howard Street
Roundabout 20 5 4
Asphalt concrete should meet the requirements in Section 5-04 of the 2008 WSDOT Standard
Specifications. The upper 2-inch wearing course of the asphalt pavement should consist of HMA Class
½-inch. The asphalt pavement below the wearing course should consist of HMA Class ¾-inch. The
asphalt binder should be PG64-22. Crushed surfacing material should meet the gradation requirements in
Section 9-09.3(9) of the 2008 WSDOT Standard Specifications. The top 2 inches of crushed surfacing
material should consist of crushed surfacing top course (CSTC) with the remainder consisting of crushed
surfacing base course (CSBC). Gravel borrow material should meet the gradation requirements in
Section 9-03.14(1) of the 2008 WSDOT Standard Specifications.
Crushed surfacing should be compacted in accordance with Section 4-04.3(5) of the 2008
WSDOT Standard Specifications. Alternatively, the maximum dry density could be determined by the
ASTM D1557 test procedure. Prevention of road-base saturation is essential for pavement durability;
thus, efforts should be made to limit the amount of water entering the base course.
3.5.4 PAVEMENT OVERLAY RECOMMENDATIONS
During the field exploration program, a visual reconnaissance of the relative amount and severity
of both alligator and transverse cracking was performed. Based on the relative amount and severity of
alligator and transverse cracking of the asphalt surface, a ranking of between 1 and 5 was assigned to the
existing pavement surface. The ranking system used for this project is based on a subjective visual
ranking system developed by AASHTO (AASHTO 1993) for estimating structural layer coefficients in
evaluating asphalt overlay thickness. A ranking of 1 would be generally equivalent to an asphalt surface
showing little wear, while a ranking of 5 indicates general failure of the pavement. The pavement located
along Sims Way and Howard Street has very little alligator cracking, and would have a visual ranking of
1 according to the AASHTO system. The table below summarizes the criteria used in the ranking system
and provides AASHTO’s suggested range of equivalent structural coefficients for each ranking.
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VISUAL PAVEMENT RANKING SYSTEM
Surface Condition Ranking
Equivalent Structural
Coefficient, a1
Little or no alligator cracking and/or only low-severity transverse cracking 1 0.35
< 10 percent low-severity alligator cracking and/or
< 5 percent medium- and high-severity transverse cracking 2 0.25
> 10 percent low-severity alligator cracking and/or
< 10 percent medium-severity alligator cracking and/or
> 5 – 10 percent medium- and high-severity transverse cracking 3 0.20
> 10 percent medium-severity alligator cracking and/or
< 10 percent high-severity alligator cracking and/or
> 10 percent medium- and high-severity transverse cracking 4 0.14
> 10 percent high-severity alligator cracking and/or
> 10 percent high-severity transverse cracking 5 NA
The thickness of the required asphalt overlay was determined in general accordance with the
AASHTO overlay design procedure. The structural number of the existing pavement, SNeff, was
determined by using the following formula:
SNeff = D1*a1+D2*a2
Where D1 = Average thickness of asphalt pavement (inches)
a1 = Structural coefficient of pavement based on pavement distress (see Table 1)
D2 = Average thickness of gravel base coarse (inches)
a2 = Structural coefficient of gravel base course
In the three borings advanced along Sims Way, the existing pavement section varied from
between 6 and 10 inches thick. For pavement overlay design, we assumed a 6-inch thick pavement
section. The Howard Street pavement section is about 2½ inches thick. This thickness was utilized in the
Howard Street overlay design.
The base course material showed some signs of degradation and/or contamination by fines.
Consequently, a reduced structural coefficient of 0.08 was used for the gravel base course material (the
typical structural layer coefficient of gravel base course material is 0.14). For pavement overlay design, a
crushed-surfacing base course thickness of 6 inches was assumed.
The required structural number of the overlay, SNol, was determined by subtracting the structural
coefficient of the existing pavement, SNeff, from the required structural number, SNf, summarized above.
The required thickness of overlay was determined by dividing SNol by the structural coefficient of the
asphalt overlay, aol. A structural number of 0.44 was selected for the asphalt overlay. A summary of the
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effective structural number, structural number of the overlay, and recommended overlay thickness is
provided below.
RECOMMENDED OVERLAY PAVEMENT THICKNESS
Location
Existing
Asphalt
Thickness
(inches) SNf SNeff SNol
Overlay
Thickness
(inches)
Sims Way 6 3.90 2.58 1.32 3
Howard Street 2½ 2.40 1.36 1.04 2½
Sims Way/Howard Street
Roundabout 6 4.16 2.58 1.58 4
Sims Way/Thomas Street
Roundabout 6 4.03 2.58 1.45 3½
Discovery Road/Howard Street
Roundabout 2½ 2.52 1.36 1.16 3
The overlay thicknesses provided above assume that the pavement has not been milled. If the
surface is milled prior to overlaying, the overlay thickness provided above should be increased per each
inch of existing pavement removed by milling. The thickness of the pavement overlay should be
increased by ¾ inch for each inch of existing pavement milled.
New asphalt concrete pavement should meet the requirements specified in Section 3.5.3 of this
report.
3.6 STORMWATER INFILTRATION
Our evaluation of the site infiltration rates for the Sims Way/Howard Street Roadway
Improvement project conforms to the approach presented in the 2005 Stormwater Management Manual of
Western Washington (2005 Stormwater Management Manual) published by the Washington State
Department of Ecology (WSDOE 2005). A preliminary assessment of the long-term infiltration rate was
evaluated by comparing the USDA Soil Textural Classification to the tabulated design long-term
infiltration rates proposed in Table 3.7 of the 2005 Stormwater Management Manual. The design long-
term infiltration rates presented in Table 3.7 were determined from case histories of shallow pond sites
underlain by a high groundwater table.
Proper operation and long-term maintenance are essential in ensuring the long-term infiltration
rates provided in this section of the report.
APPENDIX F
V. Appendicies
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3.6.1 LOGAN STREET LOCATION
At the location of the proposed detention pond located along Logan Street; relatively clean (i.e.
low fines content), uniformly graded, advance outwash was encountered below the glacial till at a depth
of about 22½ ft below the ground surface (BGS). The advance outwash encountered at this depth has a
USDA Textural Classification of Sand. According to Table 3.7 of the 2005 Stormwater Management
Manual, Sand has a long-term infiltration rate of 2 inches per hour.
The long-term infiltration rates determined by correlation to the USDA textural classification
assume a minimal amount of compaction (or glacial over-consolidation) and no cementation of the soil
particles. The advance outwash has been glacially over-consolidated; consequently, the long-term
infiltration rate is likely less than the value presented above. According to Pitt (2003), the saturated
hydraulic conductivity (and design infiltration rate) for advance outwash (i.e. glacially consolidated,
clean, uniformly graded sand ) is likely less than an order of magnitude lower then the saturated hydraulic
conductivity (and design infiltration rate) for unconsolidated soil of similar composition. Consequently,
we recommend assuming a preliminary long-term design infiltration rate of 1 inch per hour for ponds
underlain by advance outwash. Prior to final design of the infiltration pond proposed at this location, we
recommend that the long-term design infiltration tests be verified through in-situ testing.
In order to infiltrate stormwater at the infiltration site located adjacent to Logan Street, the glacial
till located between the bottom of the pond and about 22½ ft BGS will need to overexcavated and
replaced with free-draining import fill such as Gravel Backfill for Drains meeting the requirements of
Section 9-03.12(4) of the 2008 WSDOT Standard Specifications. The material should be place without
compaction.
As an alternative to completely overexcavating and replacing the glacial till, large-diameter
columns consisting of free-draining import fill such as Gravel Backfill for Drains could be placed
between the planned pond bottom and the underlying advance outwash. The large-diameter holes could
be installed with a large diameter, solid-stem auger drill rig. Upon reaching the column bottom, the base
of the column should be cleaned of any disturbed soil.
The gravel filled columns would classify as an underground injection well per Chapter 173-218
of the Washington Administrative Code (WAC). Underground injection wells are regulated by and must
be permitted with the Washington State Department of Ecology prior to construction. Chapter 173-218-
090 of the WAC requires that underground injection wells used for stormwater management not discharge
directly into the groundwater table.
Per Table 5.2 of the Guidance for UIC Wells that Manage Stormwater Manual (UIC Well
Manual) published by the Washington State Department of Ecology (WSDOE 2006), the required vertical
separation between the base of the underground injection well and the groundwater table must be 10 ft or
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greater. The 10 ft minimum depth of separation between the base of the underground injection well and
the site groundwater table includes the effects of groundwater mounding below the base of the facility. If
the facility will handle a significant amount of stormwater and the groundwater table is relatively close to
the base of the underground injection well, a mounding analysis may be necessary to determine the
impact of the facility on the site groundwater level.
Groundwater was not encountered within the depth explored (about 9 ft below the base of the
advance outwash unit) at the time of drilling (late June) in boring B-6. Boring B-6 was completed at a
time period when groundwater levels are generally falling and groundwater would be at an intermediate
level between the seasonal high and seasonal low groundwater level. Seasonal low groundwater levels
generally occur in late summer, while seasonal high groundwater levels generally occur in the spring.
Consequently, if underground injection wells are selected to help infiltrate groundwater, we recommend
that an additional boring be completed at the proposed pond site and that a monitoring well be installed to
more accurately access the site groundwater levels.
Dependent on the pollutant loading of the stormwater, pre-treatment of the stormwater may be
required prior to infiltration with the underground injection wells.
3.6.2 ALL OTHER LOCATIONS
Based on conditions encountered in the explorations completed in other portions of the project
site, glacial till generally underlies the site at shallow depth (i.e. within about 5 ft of the existing grades).
Glacial till typically consists of dense to very dense, silty to very silty sand with variable gravel content.
Though glacial till typically has a USDA classification of Sandy Loam, glacial till tends to have a very
low permeability because of its compactness. Though some infiltration will occur in the glacial till, the
infiltration rate is expected to be below that of a Silt Loam (0.125 inches per hour). Based on our
previous experience, dense to very dense glacial till has field infiltration rates of 0.05 to 0.07 inches per
hour. Therefore, infiltration of site stormwater in regional detention ponds underlain by glacial till is
likely infeasible. Infiltration of stormwater in rain gardens may be feasible, provided sufficient storage is
available to handle the design storm flow.
APPENDIX F
V. Appendicies
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4.0 REVIEW OF DOCUMENTS AND CONSTRUCTION OBSERVATIONS
Landau Associates recommends that we review the geotechnical-related portions of the plans and
specifications for the proposed project in advance of project bidding. The purpose of the review is to
verify that the recommendations presented in this geotechnical report have been properly interpreted and
implemented in the design and specifications.
We recommend that monitoring, testing, and consultation be provided during construction to
confirm that the conditions encountered are consistent with those indicated by our explorations, to
provide expedient recommendations should conditions be revealed during construction that differ from
those anticipated, and to evaluate whether geotechnical-related activities comply with project plans and
specifications and the recommendations contained in this report. Such geotechnical-related activities
include: subgrade preparation, structural fill placement and compaction, trench backfill and compaction,
retaining wall foundation subgrade preparation, observation of the prepared roadway subgrade, and other
geotechnical-related earthwork activities. The purpose of these services would be to observe compliance
with the design concepts, specifications and recommendations of this report, and in the event subsurface
conditions differ from those anticipated before the start of construction, provide revised recommendations
appropriate to the conditions revealed during construction. Landau Associates would be pleased to
provide these services for you.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
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6.0 REFERENCES
American Association of State Highway and Transportation Officials (AASHTO). 1993. Guide for
Design of Pavement Structures. American Association of State Highway and Transportation Officials,
Washington, D.C.
American Association of State Highway and Transportation Officials (AASHTO). 2002. Standard
Specifications for Highway Bridges. Seventeenth Edition. American Association of State Highway and
Transportation Officials.
Asphalt Institute. 1981. Thickness Design. Asphalt Pavements for Highways & Streets Manual Series
No. 1 (MS-1).
Pitt, R., Chen, S.E., Clark, S., Lantrip, J., Ong, C.K., and J. Voorhees. 2003. Infiltration Through
Compacted Urban Soils and Effects on Biofiltration Design, Stormwater and Urban Water Systems
Modeling, Models, and Applications to Urban Water Systems, CHI, Guelph, Ontario, W. James (ed), Vol.
11. pp. 217-252.
Schasse, H.W. and S.L. Slaughter. 2005. Geologic Map of the Port Townsend South and Part of the Port
Townsend North 7-5-Minute Quadrangles, Jefferson County, Washington. Washington Division of
Geology and Earth Resources, Geologic Map GM-57.
Transpo Group. 2008. Draft Traffic Analysis, Sims Way/Howard Street Improvements. Report prepared
for WHPacific and the City of Port Townsend. July.
USGS. 2007. Earthquake Ground Motion Parameters Software Program. Version 5.0.8.
WSDOE. 2005. Stormwater Management Manual for Western Washington. Washington State
Department of Ecology. Vol. III. February.
WSDOE. 2006. Guidance for UIC Wells that Manage Stormwater. Washington State Department of
Ecology Publication Number 05-10-067.
WSDOT. 2008a. Bridge Design Manual. Washington State Department of Transportation Publication
M23-50.02.
WSDOT. 2008b. Standard Specifications for Road, Bridge, and Municipal Construction. Washington
State Department of Transportation.
WSDOT. 2008c. WSDOT Pavement Design Guide. URL: http://training.ce.washington.edu/WSDOT/.
Accessed July 18.
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
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Sims Way / Howard StreetRoadway ImprovementsPort Townsend, Washington Vicinity Map Figure1
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\
0
1
0
\
M
a
p
D
o
c
s
\
F
i
g
1
.
m
x
d
6
/
2
3
/
2
0
0
8
Seattle
Tacoma
Port Townsend
Spokane
Everett
ProjectLocation
Project Area
W a s h i n g t o nW a s h i n g t o n
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
TP-1
B-
3
B-
2
TP-6
TP-10
TP-5
TP-9
TP-4
TP-8
TP-3TP-2
24
8
25
0
260
260260
250
25
6
25
6
25
4
254
252252
254
246
2
4
4
244
246
252252
252
252
2
5
0
25
2
252252
2
5
2
25
6
25
6
24
0
24
0
2
3
2
23
0
23
2
2
4
0
23
8
23
6 23
4
232
0 300 600
Scale in Feet
Note
Black and white reproduction of
this color original may reduce its
effectiveness and lead to incorrect
interpretation.
1.
Sims Way/Howard Street
Improvement Project
Port Townsend, Washington Site and Exploration Plan
FigureLA
N
D
A
U
A
S
S
O
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I
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E
S
,
I
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C
.
|
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\
5
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)
"
F
i
g
u
r
e
2
A
"
7
/
2
3
/
2
0
0
8
Legend
Proposed Test Pit Location and Designation
Proposed Boring Location and Designation
TP-6
B-3
B-7
Ma
t
c
h
l
i
n
e
-
F
o
r
C
o
n
t
i
n
u
a
t
i
o
n
S
e
e
F
i
g
u
r
e
2
B
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
B-6
B-4
B-3
B-2
B-1
232
230
230230
220220
210
220
218218
22
4224
226226
216216
21
621
6
2
1
0
20
2
20
2
2
1
6
2
1
4
2
1
4
190
180
200
160
170
220 218236
238
238
236
234
2
2
0
19
0
224
226
228
210
220
230
232
23
0 22
8
226
220
20
0
240
238
236
234
232
0 300 600
Scale in Feet
Note
Black and white reproduction of
this color original may reduce its
effectiveness and lead to incorrect
interpretation.
1.
Sims Way/Howard Street
Improvement Project
Port Townsend, Washington Site and Exploration Plan
FigureLA
N
D
A
U
A
S
S
O
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I
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S
,
I
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|
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7
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2
3
/
2
0
0
8
Legend
Proposed Test Pit Location and Designation
Proposed Boring Location and Designation
TP-6
B-3
B-7
Matchline - For Continuation See Figure 2A
APPENDIX F
V. Appendicies
Appendix F - Geotechnical Report
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
APPENDIX A
Field Explorations
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
5/5/09 Y:\550\049.010\R\Sims Way Howard Street_rpt.doc A-1 LANDAU ASSOCIATES
APPENDIX A
FIELD EXPLORATIONS
Subsurface conditions at the site were explored between June 25 and June 27, 2008. The
exploration program consisted of advancing and sampling seven exploratory borings (B-1 through B-7)
and ten test pits (TP-1 through TP-10) at the approximate locations illustrated on the Site and Exploration
Plan (Figure 2 of this report). The exploratory borings were advanced to depths of between 15½ and 31½
ft below the existing ground surface (BGS) using hollow-stem auger drilling techniques. Holocene
Drilling, Inc. of Fife, Washington advanced the boring under subcontract to Landau Associates. The test
pits were excavated to depths ranging from about 5 to 8 ft BGS using a rubber-tired backhoe. The test
pits were excavated using a rubber-tired backhoe supplied and operated by the City of Port Townsend.
The explorations were placed at locations selected or approved by WHPacific or the City of Port
Townsend and were located in the field using a Trimble™ GPS system. The test pit locations were
transferred onto a site map provided by WHPacific. The ground surface elevation at the test pit locations
was determined from the above-referenced site map.
The field explorations were coordinated and monitored by a geotechnical engineer from our staff,
who also obtained representative soil samples, maintained a detailed record of observed subsurface soil
and groundwater conditions, and described the soil encountered by visual and textural examination. Each
representative soil type observed was described using the soil classification system shown on Figure A-1,
in general accordance with ASTM D2488, Standard Recommended Practice for Description of Soils
(Visual-Manual Procedure). Logs of the exploratory borings are presented on Figures A-2 through A-8.
Logs of the test pit explorations are presented on Figures A-9 through A-13. These logs represent our
interpretation of subsurface conditions identified during the field explorations. The stratigraphic contacts
shown on the individual logs represent the approximate boundaries between soil types; actual transitions
may be more gradual. Also, the soil and groundwater conditions depicted are only for the specific dates
and locations reported and, therefore, are not necessarily representative of other locations and times. A
further discussion of the soil and groundwater conditions observed is contained in the text portion of this
report.
Disturbed samples of the soil encountered from the borings were obtained at frequent intervals
using a 1.5-inch inside diameter (ID) Standard Penetration Test (SPT) split-spoon sampler or a 2.5-inch
ID California Sampler. The sampler was driven up to 18 inches (or a portion thereof) into the undisturbed
soil ahead of the auger bit with a 140-lb automatic hammer falling a distance of approximately 30 inches.
The number of blows required to drive the sampler for the final 12 inches (or portion thereof) of soil
penetration, is noted on the boring logs adjacent to the appropriate sample notation. Soil samples
collected in this manner were taken to our laboratory for further examination and testing. Bulk
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
5/5/09 Y:\550\049.010\R\Sims Way Howard Street_rpt.doc A-2 LANDAU ASSOCIATES
representative soil samples of the drill cuttings from the upper portion of borings B-3 and B-5 were
collected for the purpose of completed modified Proctor and CBR laboratory testing. Upon completion of
drilling and sampling, the boreholes were abandoned in general accordance with the requirements of
WAC 173-160 and patched with fast-setting concrete.
Representative, disturbed bag samples of the soil encountered in test pit explorations were
obtained at selected intervals and taken to our laboratory for further examination and testing. Bulk
representative soil samples of the subgrade soil were collected from test pit locations (TP-2 and TP-5) for
the purpose of completed modified Proctor and CBR laboratory testing. These samples were submitted to
Upon completion of excavating and sampling, the test pits were backfilled with the backhoe. The test pits
were compacted by tamping with the backhoe bucket.
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
A-1
(Appreciable amount of
fines)
GRAVEL WITH FINES
(Little or no fines)
(Liquid limit greater than 50)
MH
SP
GRAVEL AND
GRAVELLY SOIL
Primary Constituent:
Secondary Constituents:
Additional Constituents:
>
_
_
_
_
50% - "GRAVEL," "SAND," "SILT," "CLAY," etc.
50% - "very gravelly," "very sandy," "very silty," etc.
30% - "gravelly," "sandy," "silty," etc.
15% - "with gravel," "with sand," "with silt," etc.
5% - "trace gravel," "trace sand," "trace silt," etc., or not noted.
> 30% and <
> 15% and <
> 5% and <
<
NOTES:
1. USCS letter symbols correspond to symbols used by the Unified Soil Classification System and ASTM classification methods. Dual letter symbols (e.g.,
SP-SM for sand or gravel) indicate soil with an estimated 5-15% fines. Multiple letter symbols (e.g., ML/CL) indicate borderline or multiple soil
classifications.
2. Soil descriptions are based on the general approach presented in the Standard Practice for Description and Identification of Soils (Visual-Manual
Procedure), outlined in ASTM D 2488. Where laboratory index testing has been conducted, soil classifications are based on the Standard Test
Method for Classification of Soils for Engineering Purposes, as outlined in ASTM D 2487.
3. Soil description terminology is based on visual estimates (in the absence of laboratory test data) of the percentages of each soil type and is defined as
follows:
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
(1 of 2)
SAND WITH FINES
OH
Inorganic silt; micaceous or diatomaceous fine sand
Wood, lumber, wood chips
Rock (See Rock Classification)
USCS
LETTER
SYMBOL(1)TYPICAL
DESCRIPTIONS (2)(3)
Organic clay of medium to high plasticity; organic silt
PAVEMENT
SAND AND
SANDY SOIL
WD
PT
Inorganic silt and very fine sand; rock flour; silty or clayey fine
sand or clayey silt with slight plasticity
FI
N
E
-
G
R
A
I
N
E
D
S
O
I
L
(M
o
r
e
t
h
a
n
5
0
%
o
f
m
a
t
e
r
i
a
l
is
s
m
a
l
l
e
r
t
h
a
n
N
o
.
2
0
0
sie
v
e
s
i
z
e
)
Well-graded gravel; gravel/sand mixture(s); little or no fines
(Liquid limit less than 50)
(Little or no fines)
GM
RK
7/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
C
S
W
S
D
O
T
1
O
F
2
Figure
Construction debris, garbage
LETTER
SYMBOL
Poorly graded gravel; gravel/sand mixture(s); little or no fines
AC or PC
DB
Asphalt concrete pavement or Portland cement pavement
GRAPHIC
SYMBOL
ROCK
TYPICAL DESCRIPTIONSOTHER MATERIALS
Soil Classification System and Key
SILT AND CLAY
Well-graded sand; gravelly sand; little or no fines
Poorly graded sand; gravelly sand; little or no fines
SILT AND CLAY
Soil Classification System
GP
GRAPHIC
SYMBOL
Clayey sand; sand/clay mixture(s)
(More than 50% of
coarse fraction
retained on No. 4
sieve)
MAJOR
DIVISIONS
CH
GW
CL
SC
SM
(Appreciable amount of
fines)
(More than 50% of
coarse fraction passedthrough No. 4 sieve)
Inorganic clay of low to medium plasticity; gravelly clay; sandyclay; silty clay; lean clay
(M
o
r
e
t
h
a
n
5
0
%
o
f
m
a
t
e
r
i
a
l
i
s
la
r
g
e
r
t
h
a
n
N
o
.
2
0
0
s
i
e
v
e
s
i
z
e
)
CO
A
R
S
E
-
G
R
A
I
N
E
D
S
O
I
L
OL
Peat; humus; swamp soil with high organic content
DEBRIS
WOOD
Silty sand; sand/silt mixture(s)
Organic silt; organic, silty clay of low plasticity
CLEAN SAND
CLEAN GRAVEL
HIGHLY ORGANIC SOIL
ML
SW
GC Clayey gravel; gravel/sand/clay mixture(s)
Silty gravel; gravel/sand/silt mixture(s)
Inorganic clay of high plasticity; fat clay
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
PVC Screen(0.010-inch Slot Size)
Flush-Mount
Monument
10-20 Sand
1
Approximate water elevation at other time(s). When multiple water levels are
obtained other than ATD, only a representative range is shown. See text for additionalinformation.
Note:
Approximate water elevation at time of drilling (ATD).
Pocket Penetrometer, tsf
Torvane, tsf
Photoionization Detector VOC screening, ppm
Moisture Content, %
Dry Density, pcf
Material smaller than No. 200 sieve, %
Grain Size - See separate figure for data
Atterberg Limits - See separate figure for data
Vane Shear Test
Other Geotechnical Testing
Chemical Analysis
A-1
Slough Backfill
Groundwater levels can fluctuate due to precipitation, seasonal conditions, and other
factors.
PP = 1.0
TV = 0.5
PID = 100
W =10
D = 120
-200 = 60
GS
AL
VST
GT
CA
Code
PVC Blank Casing
Description
Bentonite Chips
Well Log Graphics
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
(2 of 2)
DescriptionCode
Sample Identification Number
Recovery Depth Interval
Sample Depth Interval
Bentonite Grout
Above-Ground
Monument
Groundwater
SAMPLE NUMBER & INTERVAL
3.25-inch O.D., 2.42-inch I.D. Split Spoon
2.00-inch O.D., 1.50-inch I.D. Split Spoon
Shelby Tube
Grab Sample
Single-Tube Core Barrel
Double-Tube Core Barrel
Other - See text if applicable
300-lb Hammer, 30-inch Drop
140-lb Hammer, 30-inch Drop
Pushed
Rotosonic
Air Rotary (Rock)
Wash Rotary (Rock)
Other - See text if applicable
Field and Lab Test Data
SAMPLER TYPE
a
b
c
d
e
f
g
1
2
3
4
5
6
7
7/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
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5
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4
9
.
0
1
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.
G
P
J
S
C
S
W
S
D
O
T
2
O
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2
Figure
VWP
Portion of Sample Retainedfor Archive or Analysis
Drilling and Sampling Key
Soil Classification System and Key
End Cap
pPPvNbIX W
Vi pppendicies
pppendix W - Eeotechnical Report
50/
3"
50/
3"
50/
3"
50/
3"
50/5"
13
50/
4"
50/
3"
50/
3"
50/
5"
85
-- cobble reported by driller
-- cobble reported by driller
Gray, silty, gravelly, fine to coarse SAND(very dense, moist)
(GLACIAL TILL)
Brown to gray-brown, fine to mediumSAND with silt to trace silt (very loose to
loose, wet)
(ABLATION TILL)
Dark brown, gravelly, silty, fine to coarse
SAND with scattered to numerous fine
roots (very loose, wet)
(TOPSOIL)
50/
4"
85
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =54
W =17
b2S-7
S-6
S-5
S-4
S-3
S-2b
S-2a
S-1b
b2
b2
b2
b2
a2
a2
a2
a2
Boring Completed 06/26/08
Total Depth of Boring = 30.4 ft.
S-1a
SM
SM
SP-SM
Gr
a
p
h
i
c
S
y
m
b
o
l
SAMPLE DATA
Holocene Drilling
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:Date:De
p
t
h
(
f
t
)
Non-Standard N-Value
550049.010LAI Project No:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
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r
v
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l
06/26/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
Te
s
t
D
a
t
a
US
C
S
S
y
m
b
o
l
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
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:
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5
5
0
\
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4
9
.
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0
\
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5
0
0
4
9
.
0
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0
.
G
P
J
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O
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B
O
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I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
55
0
0
4
9
.
0
1
7
/
2
4
/
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8
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:
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5
5
0
\
0
4
9
.
0
1
0
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0
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4
9
.
0
1
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.
G
P
J
S
O
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L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-2
B-1
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Not Measured
PlasticLimit
Mobile B-61, 4 ID HSA
CTM
Log of Boring B-1
Bl
o
w
s
/
F
o
o
t
0
5
10
15
20
25
30
35
Sa
m
p
l
e
r
T
y
p
e
Notes:
10 20 30 40
SPT N-Value
20 40 60 80
Moisture Content (%)
20 40 60 80
Fines Content (%)
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
(77wTBWL u
:e (ppKnxiFiKs
(ppKnxix u l hKotKFhniFJl 6Kport
42
W =10
GS
100/6"
100/5"
W =9
GS38
31
14
100/6"
35
Gray, silty, very gravelly, fine to medium
SAND (very dense, moist)
(GLACIAL TILL)
Dark gray, silty, fine to coarse SAND withgravel (medium dense, moist to wet)
(FILL)
Grades loose, very gravelly
Gray, sandy GRAVEL to gravelly, fine to
coarse SAND (medium dense, moist)
(CRUSHED ROAD BALLAST)
W =7
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =7
W =4
a2
S-6
S-5
S-4
S-3
S-2
S-1b
S-1a
100/5"
a2
a2
a2
a2
a2
a2
Boring Completed 06/26/08
Total Depth of Boring = 16.5 ft.
a2S-7
SM
GP/
SP
Gr
a
p
h
i
c
S
y
m
b
o
l
Bl
o
w
s
/
F
o
o
t
SAMPLE DATA
Holocene Drilling
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:Date:De
p
t
h
(
f
t
)
Non-Standard N-Value
550049.010LAI Project No:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
06/26/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
US
C
S
S
y
m
b
o
l
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
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5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
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L
B
O
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I
N
G
L
O
G
W
I
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H
G
R
A
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H
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-3
B-2
Sa
m
p
l
e
r
T
y
p
e
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Not Measured
PlasticLimit
Mobile B-61, 4 ID HSA
CTM
Log of Boring B-2
Te
s
t
D
a
t
a
0
5
10
15
20
25
30
35
SM
Notes:
10 20 30 40
SPT N-Value
20 40 60 80
Moisture Content (%)
20 40 60 80
Fines Content (%)
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
AII)7(h. k
B" AppKnxiOiKs
AppKnxix k 6 cKotKOhniO\l PKport
S-4
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
S-1 Gray, very gravelly, fine to coarse SAND
with silt (very dense, moist)
(GLACIAL TILL)
Light brown, very gravelly, fine to coarse
SAND with silt (dense, moist)
(ROAD PAVEMENT STRUCTURE)
6.5 inches of asphalt concrete
148
50/
4"
50/
6"
50/
5"
148
50/
4"
S-3
50/
5"W =7
W =8
CBR
W =4GS
50/
6"
S-0
b2
b2
b2
a2
Boring Completed 06/27/08
Total Depth of Boring = 15.8 ft.
SP-
SM
SP-
SM
AC
S-2
d
LAI Project No:
Holocene Drilling
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Gr
a
p
h
i
c
S
y
m
b
o
l
550049.010
Date:Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
06/27/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
Te
s
t
D
a
t
a
Bl
o
w
s
/
F
o
o
t
Non-Standard N-Value
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-4Log of Boring B-3
SAMPLE DATA
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Not Measured
PlasticLimit
Mobile B-61, 4 ID HSA
CTM
Notes:
B-3
Sa
m
p
l
e
r
T
y
p
e
20 40 60 80
Moisture Content (%)
Fines Content (%)
0
5
10
15
20
25
30
35
20 40 60 80
SPT N-Value
10 20 30 40
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
A77)3(.E L
:r App%nOiJi%s
App%nOix L w b%ot%JhniJYl B%port
Brown, gravelly, fine to coarse SAND(dense, moist)
(ROAD PAVEMENT STRUCTURE)
10 inches of asphalt concrete
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Gray, gravelly, fine to medium SAND withsilt (medium dense to very dense, moist)
(GLACIAL TILL)
S-4
50/
5"
50/
6"
50/
5"
126
49
50/
6"
126W =9
W =10
Boring Completed 06/27/08
Total Depth of Boring = 15.5 ft.
S-3
S-2
S-1
b2
b2
a2
SP-
SM
SP
AC
a2
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Non-Standard N-Value
550049.010LAI Project No:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
De
p
t
h
(
f
t
)
Not Measured
US
C
S
S
y
m
b
o
l
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
B-4
Gr
o
u
n
d
w
a
t
e
r
Log of Boring B-4 A-5
PlasticLimit
06/27/08
Mobile B-61, 4 ID HSA
CTMGr
a
p
h
i
c
S
y
m
b
o
l
Date:Te
s
t
D
a
t
a
SAMPLE DATA
Holocene Drilling
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:20 40 60 80
20 40 60 80
Fines Content (%)
0
5
10
15
20
25
30
35
Moisture Content (%)
SPT N-Value
10 20 30 40
Notes:
Sa
m
p
l
e
r
T
y
p
e
LiquidLimit
Figure
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Bl
o
w
s
/
F
o
o
t
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
R77G=T5V u
xi Rppqn%iFiqs
Rppqn%ix u f -qotqFhniFOl .qport
S-4
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
S-1 Gray, gravelly, silty, fine to coarse SAND
(very dense, moist)
(GLACIAL TILL)
Gray-brown, silty gravelly SAND (medium
dense, moist)
(ROAD PAVEMENT STRUCTURE)
6 inches of aspahlt concrete
118
50/
6"
56
50/6"
118
50/
6"
S-3
50/6"W =8
W =10
CBRW =8
GS
56
S-0
b2
b2
b2
a2
Boring Completed 06/26/08
Total Depth of Boring = 15.5 ft.
SM
SM
AC
S-2
d
LAI Project No:
Holocene Drilling Inc.
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Gr
a
p
h
i
c
S
y
m
b
o
l
550049.010
Date:Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
06/26/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
Te
s
t
D
a
t
a
Bl
o
w
s
/
F
o
o
t
Non-Standard N-Value
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-6Log of Boring B-5
SAMPLE DATA
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Not Measured
PlasticLimit
Mobile B-61, 4 ID HSA
CTM
Notes:
B-5
Sa
m
p
l
e
r
T
y
p
e
20 40 60 80
Moisture Content (%)
Fines Content (%)
0
5
10
15
20
25
30
35
20 40 60 80
SPT N-Value
10 20 30 40
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
ABB)=(5U b
:r App%nOiJi%s
App%nOix b w u%ot%JhniJYl .%port
W =6
GS
143
50/5"
50/
6"
50/6"
65
W =7
40
143
50/
5"
50/
6"
50/6"
88 88
Gray, gravelly, fine to coarse SAND with
silt (very dense, damp to moist)
(ADVANCE OUTWASH)
-- cobble reported by driller
Gray, silty, gravelly, fine to coarse SAND(very dense, moist)
(GLACIAL TILL)
Gray-brown, gravelly, fine to coarse SANDwith silt (medium dense, damp)
(ABLATION TILL)
Brown, gravelly, silty, fine to coarse SAND,
with numerous fine to medium plant roots
(medium dense, wet)
(TOPSOIL)
W =5
GS
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =26
W =10
b2
b2
b2
b2
b2
a2
a2
a2
Boring Completed 06/26/08
Total Depth of Boring = 31.5 ft.
65
S-1b
SP-SM
SP-
SM
SM
SP-SM
SM
S-1a
S-7
S-6
S-5
S-4
S-3
S-2
LAI Project No:
Gray, fine to medium SAND with graveland silt (very dense, damp to moist)
Drilling Method:
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Gr
a
p
h
i
c
S
y
m
b
o
l
SAMPLE DATA
550049.010
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
06/26/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
Te
s
t
D
a
t
a
Bl
o
w
s
/
F
o
o
t
Sa
m
p
l
e
r
T
y
p
e
Notes:
Non-Standard N-Value
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-7Log of Boring B-6
Holocene Drilling
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Not Measured
PlasticLimit
Mobile B-61, 4 ID HSA
CTM Date:
B-6
10 20 30 40
20 40 60 80
SPT N-Value
20 40 60 80
Moisture Content (%)
Fines Content (%)
0
5
10
15
20
25
30
35
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
wTTmIdbE p
j8 wpp%nOiJi%s
wpp%nOix p " )%ot%JhniJYl C%port
S-1
S-6
S-5
S-4
S-3
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Gray, silty, gravelly SAND and gravelly silty
SAND (dense to very dense, moist)
(GLACIAL TILL)
Brown, silty, gravelly SAND (medium
dense, moist)
(ROAD PAVEMENT STRUCTURE)
2.5 inches of asphalt concrete
100/
3"
100/
3"
100/
5"
100/
3"
100/6"
108
100/5"
S-2
100/
5"
100/6"
108
W =7
W =10
100/
3"
SM
a2
a2
a2
a2
a2
a2
Boring Completed 06/26/08
Total Depth of Boring = 15.4 ft.
100/
5"
SM
AC
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Ground Elevation (ft):
SOIL PROFILE
Drilled By:
Logged By:US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Gr
a
p
h
i
c
S
y
m
b
o
l
Non-Standard N-Value
550049.010
Holocene Drilling
SAMPLE DATA
06/26/08
LiquidLimit
Gr
o
u
n
d
w
a
t
e
r
Te
s
t
D
a
t
a
Bl
o
w
s
/
F
o
o
t
Sa
m
p
l
e
r
T
y
p
e
Notes:
LAI Project No:
Not Measured
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Figure
A-8Log of Boring B-7
B-7
Drilling Method:
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
SPT N-Value
PlasticLimit
Mobile B-61, 4 ID HSA
CTM Date:
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
S
O
I
L
B
O
R
I
N
G
L
O
G
W
I
T
H
G
R
A
P
H
Moisture Content (%)
10 20 30 40
20 40 60 80
Fines Content (%)
20 40 60 80
0
5
10
15
20
25
30
35
Gr
o
u
n
d
w
a
t
e
r
N
o
t
E
n
c
o
u
n
t
e
r
e
d
l==("D2L )
E/ lpp%nKixi%s
lpp%nKix ) y B%ot%xhnixJl M%port
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Not Measured
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-1
Rubber-tired Backhoe
Sa
m
p
l
e
r
T
y
p
e
Ground Elevation (ft):
GROUNDWATER
0
2
4
6
8
10
12
Log of Test Pits
Excavated By:
Notes:
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
T
E
S
T
P
I
T
L
O
G
Figure
City of Port Townsend
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Groundwater not encountered.
SM
SM
d
d
Test Pit Completed 06/25/08
Total Depth of Test Pit = 6.5 ft.
S-2
S-1
Gray, silty, fine to medium SAND with gravel(dense to very dense, damp to moist)
(GLACIAL TILL)
Gray-brown, silty, fine to coarse SAND(medium dense, moist)
(ABLATION TILL)
(TOPSOIL)
W =6
GS
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Ground Elevation (ft):
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
A-9
Not Measured
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
City of Port Townsend
CBR
W =8
GS
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-2
Excavated By:
Sa
m
p
l
e
r
T
y
p
e
Rubber-tired Backhoe
Test Pit Completed 06/25/08
Total Depth of Test Pit = 7.0 ft.
d
d
d
S-3
S-2
S-1
SM
(TOPSOIL)
SM Brown, gravelly, silty, fine to coarse SAND
(medium dense, moist)
(ABLATION TILL)
Gray, silty, gravelly, fine to coarse SAND(dense, moist to wet)
(GLACIAL TILL)
kHH0W)8\ 2
V. AppendiciesAppendix F - Geotechnical Report
Ground Elevation (ft):
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-3
Excavated By:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Rubber-tired Backhoe
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
SOIL PROFILE
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
T
E
S
T
P
I
T
L
O
G
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Not Measured
City of Port Townsend
SAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Notes:
SM
SM
d
d
Test Pit Completed 06/25/08Total Depth of Test Pit = 7.0 ft.
S-2
S-1 W =12
Gray, silty, gravelly, fine to coarse SAND
(dense to very dense, most)
(GLACIAL TILL)
Gray and brown, gravelly, silty, fine to coarse
SAND (loose to medium dense, moist to wet)
(ABLATION TILL)
(TOPSOIL)
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
FigureSims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =9
Not Measured
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Ground Elevation (ft):
City of Port Townsend
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-4
Excavated By:
Rubber-tired Backhoe
Test Pit Completed 06/25/08
Total Depth of Test Pit = 5.0 ft.
dS-2
S-1
A-10Log of Test Pits
SM
SM Gray, silty, gravelly, fine to coarse SAND
(dense, moist)
(GLACIAL TILL)
Gray, gravelly, silty, fine to coarse SAND
(medium dense, moist)
(ABLATION TILL)
(TOPSOIL)
d
I//09k83 2
O( Ippendicies
Ippendix 2 i 4eotechnicFl \eport
Ground Elevation (ft):
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-5
Excavated By:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Rubber-tired Backhoe
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
SOIL PROFILE
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
T
E
S
T
P
I
T
L
O
G
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Not Measured
City of Port Townsend
SAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Notes:
SM
SM
d
d
Test Pit Completed 06/25/08Total Depth of Test Pit = 7.0 ft.
S-2
S-1
CBR
W =8
GS
Gray, silty, fine to coarse SAND with gravel
(dense, moist)
(GLACIAL TILL)
Brown, silty, fine to coarse SAND with gravel
(medium dense, moist)
(ABLATION TILL)
(TOPSOIL)
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
FigureSims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =9
GS
Not Measured
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Ground Elevation (ft):
City of Port Townsend
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-6
Excavated By:
Rubber-tired Backhoe
Test Pit Completed 06/25/08Total Depth of Test Pit = 8.0 ft.
dS-2
S-1
A-11Log of Test Pits
SM
SM Gray, silty, fine to coarse SAND with gravel
(dense, moist)
(GLACIAL TILL)
Dark brown-gray, very silty, fine to medium
SAND with gravel (loose, moist)
(ABLATION TILL)
(TOPSOIL)
d
I//09k83 2
O( Ippendicies
Ippendix 2 i 4eotechnicFl \eport
Excavation Method:
Te
s
t
D
a
t
a
TP-7
Excavated By:
Sa
m
p
l
e
r
T
y
p
e
Ground Elevation (ft):
City of Port Townsend
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
T
E
S
T
P
I
T
L
O
G
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Notes:
Gr
a
p
h
i
c
S
y
m
b
o
l
SOIL PROFILE
Not Measured
SAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Rubber-tired Backhoe
SM
SM
d
d
Test Pit Completed 06/25/08
Total Depth of Test Pit = 5.0 ft.
S-2
S-1
W =7
GS
W =12
Gray, very silty, fine to medium SAND with
gravel (very dense, moist)
(GLACIAL TILL)
Brown-gray with iron-oxide staining, gravelly,silty, fine to coarse SAND (loose to medium
dense, wet)
(ABLATION TILL)
(TOPSOIL)
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
Figure
Not Measured
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Ground Elevation (ft):
City of Port Townsend
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-8
Excavated By:
Rubber-tired Backhoe
Test Pit Completed 06/25/08
Total Depth of Test Pit = 5.0 ft.
S-2
S-1
A-12Log of Test PitsSims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Gray-brown, gravelly, silty, fine to coarse
SAND (medium dense, moist to wet)
(ABLATION TILL)
(TOPSOIL)
- large roots at 2'
Gray, gravelly, silty, fine to coarse SAND
(dense, moist to wet)
(GLACIAL TILL)
SM
SM
0LL8J69" 1
R: 0ppendi'ies
0ppendix 1 d .eote'hni'Fl Neport
Ground Elevation (ft):
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-9
Excavated By:
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Rubber-tired Backhoe
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
SOIL PROFILE
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
T
E
S
T
P
I
T
L
O
G
1. Stratigraphic contacts are based on field interpretations and are approximate.
2. Reference to the text of this report is necessary for a proper understanding of subsurface conditions.
3. Refer to "Soil Classification System and Key" figure for explanation of graphics and symbols.
Not Measured
City of Port Townsend
SAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Notes:
SP-
SM
SP-
SM
d
d
Test Pit Completed 06/25/08
Total Depth of Test Pit = 5.0 ft.
S-2
S-1 W =8
Gray, silty, gravelly, fine to coarse SAND
(dense, moist)
(GLACIAL TILL)
Gray, silty, gravelly, fine to coarse SAND(medium dense, moist)
(ABLATION TILL)
(TOPSOIL)
GROUNDWATER
0
2
4
6
8
10
12
Groundwater not encountered.
Sa
m
p
l
e
r
T
y
p
e
FigureSims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
W =7
Not Measured
SOIL PROFILESAMPLE DATA
US
C
S
S
y
m
b
o
l
De
p
t
h
(
f
t
)
Ground Elevation (ft):
City of Port Townsend
Sa
m
p
l
e
N
u
m
b
e
r
&
I
n
t
e
r
v
a
l
Gr
a
p
h
i
c
S
y
m
b
o
l
Excavation Method:
Te
s
t
D
a
t
a
TP-10
Excavated By:
Rubber-tired Backhoe
Test Pit Completed 06/25/08Total Depth of Test Pit = 5.5 ft.
dS-2
S-1
A-13Log of Test Pits
SM
SM Gray-brown, silty, gravelly, fine to coarse
SAND with silt (dense, moist)
(GLACIAL TILL)
Red-brown, silty, gravelly, fine to coarse
SAND with silt (medium dense, moist)
(ABLATION TILL)
(TOPSOIL)
d
I//09k83 2
O( Ippendicies
Ippendix 2 i 4eotechnicFl \eport
APPENDIX B
Laboratory Testing
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
5/5/09 Y:\550\049.010\R\Sims Way Howard Street_rpt.doc B-1 LANDAU ASSOCIATES
APPENDIX B
LABORATORY TESTING
Natural moisture content determinations, fines content determinations, grain size analyses, and
Atterberg limit determinations tests were performed on selected samples to aid in soil classification.
Laboratory testing was performed in general accordance with the ASTM standard test procedures, which
are described below. The samples were checked against the field log descriptions, which were updated
where appropriate in general accordance with ASTM D2487, Standard Test Method for Classification of
Soils for Engineering Purposes.
NATURAL MOISTURE CONTENT
Natural moisture content determinations were performed on selected soil samples recovered from
the borings in general accordance with ASTM D2216. The natural moisture content is shown as W=xx
(percent of dry weight) at the respective sample depth in the column labeled “Test Data” on the summary
logs in Appendix A.
SIEVE ANALYSIS
Sieve analyses were performed on representative soil samples obtained from the borings in
accordance with ASTM D422, to provide an indication of the grain size distribution. Samples selected
for sieve analysis are designated with a “GS” in the column labeled “Test Data” on the summary boring
logs in Appendix A. The results of the sieve analyses are presented in the form of grain size distribution
curves on Figures B-1 through B-3 in this appendix.
MODIFIED PROCTOR
Large representative subgrade soils collected from borings B-3 and B-5 and from test pits TP-2
and TP-5 received modified Proctor testing. The maximum dry density and optimum water content were
determined in general accordance with ASTM D1557 test procedures. Samples selected for modified
Proctor analysis are designated with a “CBR” in the column labeled “Test Data” on the summary logs in
Appendix A. The results of the Modified Proctor testing are presented in the form of moisture-density
curves on Figures B-4 through B-7 in this appendix.
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
5/5/09 Y:\550\049.010\R\Sims Way Howard Street_rpt.doc B-2 LANDAU ASSOCIATES
CALIFORNIA BEARING RATIO
Large representative subgrade soils were collected from borings B-3 and B-5 and from test pits
TP-2 and TP-5. The subgrade samples were analyzed by Analytical Resources, Inc. (ARI) for
determination of the California Bearing Ratio (CBR). The CBR was determined in general accordance
with the ASTM D1883 test procedures. Samples selected for determination of the laboratory CBR value
are designated with a “CBR” in the column labeled “Test Data” on the summary boring logs in Appendix
A. The test results are presented in ARI’s summary report, which is included at the end of this appendix.
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
2 1 60
0
10
100
90
80
70
60
50
40
30
100 10 1 0.1 0.01 0.001
20
Soil Description
S-3
50
Fine
SM
SM
SP-SM
SM
Cobbles
64
Exploration
Number
408
S-5
Coarse
1/2
Sample
Number
SP-SM
B-2
B-2
B-3
B-5
Figure
550049.01 7/24/08 Y:\550\049.010\T\550049.010.GPJ GRAIN SIZE FIGURE
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington Grain Size Distribution
B-6
10
S-0
S-0
S-6
Silty, fine to coarse SAND with gravel
Silty, very gravelly, fine to coarse SAND
Very gravelly, fine to coarse SAND with silt
Gravelly, silty, fine to coarse SAND
9
Coarse
4
8
5
5.0
10.0
1.0
1.5
25.0 Gravelly, fine to coarse SAND with silt
Symbol
Fine
U.S. Sieve Numbers
14016 200
Depth
(ft)
Natural
Moisture (%)
3/863 1001.5 2010 3043
Pe
r
c
e
n
t
F
i
n
e
r
b
y
W
e
i
g
h
t
Sand
Hydrometer
Medium
3/4
U.S. Sieve Opening in Inches
B-1
14
Silt or ClayGravel
Unified Soil
Classification
Grain Size in Millimeters
NZZBA/\, g
di Nppendicies
Nppendix g o Yeotechnical Weport
2 1 60
0
6
0.001
10
20
30
40
50
60
70
100
90
80
100 10 1 0.1 0.01
Fine
6
S-2
SP-SM
SM
SM
SM
SM
Soil DescriptionExploration
Number
408
Sample
Number
50
Coarse
1/2
S-1
B-6
TP- 1
TP- 2
TP- 5
TP- 6
S-7
Figure
550049.01 7/24/08 Y:\550\049.010\T\550049.010.GPJ GRAIN SIZE FIGURE
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington Grain Size Distribution
8
S-1
S-1
Fine to medium SAND with gravel and silt
Silty, fine to medium SAND with gravel
Gravelly, silty, fine to coarse SAND
Silty, fine to coarse SAND with gravel
Very silty, fine to medium SAND with gravel
6
8
9
30.0
6.0
1.0
2.0
3.0
Cobbles
6
Depth
(ft)
U.S. Sieve Numbers
3/8 14043
Natural
Moisture (%)Symbol
2001.5
Fine
16 100
Sand
U.S. Sieve Opening in Inches
303/4 3 10
Hydrometer
MediumCoarse
B-2
2014
Silt or ClayGravel
Unified Soil
Classification
Grain Size in Millimeters
Pe
r
c
e
n
t
F
i
n
e
r
b
y
W
e
i
g
h
t
4
mZZBA/:, T
dn mppendicies
mppendix T i geotechnical Weport
0
50
60
100 0.0010.010.1
1
30
1
10
90
80
70
60
40
100
20
10
41/2
Coarse
Sample
Number
8 403/4
Exploration
Number
Cobbles Coarse Medium
Hydrometer
Sand
20
4.5
Grain Size Distribution
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
550049.01 7/24/08 Y:\550\049.010\T\550049.010.GPJ GRAIN SIZE FIGURE
Figure
50
Fine
7 Very silty, fine to medium SAND with gravelS-2 SM
Soil Description
6
TP- 7
1403/8
U.S. Sieve Numbers
Fine
3 163
Depth
(ft)
1.5 100621430104
Pe
r
c
e
n
t
F
i
n
e
r
b
y
W
e
i
g
h
t
Grain Size in Millimeters
Unified Soil
Classification
Silt or Clay
200
U.S. Sieve Opening in Inches
Symbol Natural
Moisture (%)
B-3
Gravel
HYYDhzIV W
Fo Hppendicies
Hppendix W C weotechnical \eport
5 %
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
C
O
M
P
A
C
T
I
O
N
F
I
G
U
R
E
(
P
A
R
A
B
O
L
A
)
Figure
Moisture-Density Relationship
136
6 %
134.8 pcf
ASTM D 1557B
Very gravelly, fine to coarse SAND
with silt
B-3 Sample S-0 located at a depth of 1
ft.
138 pcf
20 %
B-4
104
80
84
88
92
144
100
140
108
112
116
120
124
128
132
Maximum Dry Density:
96
Percent Greater Than 3/8" Sieve:
Test Method:
Water Content in Percent
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Dr
y
D
e
n
s
i
t
y
i
n
P
o
u
n
d
s
p
e
r
C
u
b
i
c
F
o
o
t
Material Description:
Curves of 100% Saturation for
Specific Gravity equal to:
* Based on the CAA method.
ROCK CORRECTED RESULTS*
Corrected Maximum Dry Density:
Optimum Water Content:
Corrected Optimum Water Content:
2.60
2.70
2.80
Material Source:
TEST RESULTS (less than 3/8 material)
0 10203040
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
7 %
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
C
O
M
P
A
C
T
I
O
N
F
I
G
U
R
E
(
P
A
R
A
B
O
L
A
)
Figure
Moisture-Density Relationship
136
7.5 %
135 pcf
ASTM D 1557B
Gravelly, silty, fine to coarse SAND
B-5 Sample S-0 located at a depth of 2
ft.
137 pcf
11 %
B-5
104
80
84
88
92
144
100
140
108
112
116
120
124
128
132
Optimum Water Content:
96
* Based on the CAA method.
TEST RESULTS (less than 3/8" material)
Water Content in Percent
Dr
y
D
e
n
s
i
t
y
i
n
P
o
u
n
d
s
p
e
r
C
u
b
i
c
F
o
o
t
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Material Source:
Material Description:
ROCK CORRECTED RESULTS*
Percent Greater Than 3/8" Sieve:
Corrected Maximum Dry Density:
Curves of 100% Saturation for
Specific Gravity equal to:
Corrected Optimum Water Content:
2.60
2.70
2.80
Test Method:
Maximum Dry Density:
0 10203040
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
8 %
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
C
O
M
P
A
C
T
I
O
N
F
I
G
U
R
E
(
P
A
R
A
B
O
L
A
)
Figure
Moisture-Density Relationship
136
8.3 %
133 pcf
ASTM D 1557B
Gravelly, silty, fine to coarse SAND
TP-2 Sample S-1 located at a depth of
1 ft.
135 pcf
12 %
B-6
104
80
84
88
92
144
100
140
108
112
116
120
124
128
132
Optimum Water Content:
96
* Based on the CAA method.
TEST RESULTS (less than 3/8" material)
Water Content in Percent
Dr
y
D
e
n
s
i
t
y
i
n
P
o
u
n
d
s
p
e
r
C
u
b
i
c
F
o
o
t
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Material Source:
Material Description:
ROCK CORRECTED RESULTS*
Percent Greater Than 3/8" Sieve:
Corrected Maximum Dry Density:
Curves of 100% Saturation for
Specific Gravity equal to:
Corrected Optimum Water Content:
2.60
2.70
2.80
Test Method:
Maximum Dry Density:
0 10203040
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report
7 %
55
0
0
4
9
.
0
1
7
/
2
4
/
0
8
Y
:
\
5
5
0
\
0
4
9
.
0
1
0
\
T
\
5
5
0
0
4
9
.
0
1
0
.
G
P
J
C
O
M
P
A
C
T
I
O
N
F
I
G
U
R
E
(
P
A
R
A
B
O
L
A
)
Figure
Moisture-Density Relationship
136
7.8 %
131.5 pcf
ASTM D 1557A
Silty, fine to coarse SAND with gravel
TP-5 Sample S-1 located at a depth of
2 ft.
134 pcf
16 %
B-7
104
80
84
88
92
144
100
140
108
112
116
120
124
128
132
Optimum Water Content:
96
* Based on the CAA method.
TEST RESULTS (less than #4 sieve material)
Water Content in Percent
Dr
y
D
e
n
s
i
t
y
i
n
P
o
u
n
d
s
p
e
r
C
u
b
i
c
F
o
o
t
Sims Way/Howard Street
Roadway Improvements
Port Townsend, Washington
Material Source:
Material Description:
ROCK CORRECTED RESULTS*
Percent Greater Than #4 Sieve:
Corrected Maximum Dry Density:
Curves of 100% Saturation for
Specific Gravity equal to:
Corrected Optimum Water Content:
2.60
2.70
2.80
Test Method:
Maximum Dry Density:
0 10203040
APPENDIX F
V. AppendiciesAppendix F - Geotechnical Report