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The Riley Group Inc.
GEOTECHNICAL ENGINEERING REPORT
Proposed Walgreens Drugstore
4105 & 4111 NE 4th Street
Renton, WA 98059
Project No. 2007-254
Prepared By:
The Riley Group, Inc.
17522 Bothell Way NE �
Bothell, WA 98011
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Prepared for:
Mr. Robert Sherry
Phillips Edison & Company
175 East 400 South, Suite 402
Salt Lake City, Utah 84111 ��,
C1TvOfRENTON ,
November 14, 2007 RE���u�0
�AY 13 2��B
ServinQ the Pacific Northwest �U�L��'����������
Main Office: 17522 Bothell Way NE,Bothell,WA 98011
Tel(425)415-0551 • Fax(425) 415-0311
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The Riley Group Inc.
November 14, 2007
Mr. Robert Sherry
Phillips Edison& Company
175 East 400 South, Suite 402
Salt Lake City, Utah 84111
Subject: Geotechnical Engineering Report
Proposed Walgreens Drugstore
4105 & 4111 NE 4`h Street
Renton, WA 98059
Project No. 2007-254
Dear Mr. Sherry:
As requested, The Riley Group, Inc. (Riley) has performed a geotechnical engineering
study for the above referenced site. The attached report presents our findings and
recommendations for the geotechnical aspects of the project design and construction.
Our field exploration indicates that the site is generally underlain by 5 to 10 feet of fill
overlying medium dense to very dense silty SAND with gravel. The fill consists of loose to
dense sandy GRAVEL to silty SAND with some gravel and trace wood debris.
Groundwater seepage was not encountered during the field exploration.
Based on the subsurface soil condition, the fill seems to be placed during the site grading
and utilities for the gas station and car wash before. The loose fill underlain the site is not
suitable for directly supporting the proposed building foundations and floor slab. If the
loose fill is encountered below the proposed footing subgrade, it should be compacted. If
the organic soil encountered, it should be over-excavated and replaced with structural fill.
The subgrade condition should be verified by a geotechnical engineer during construction.
Riley recommends that the proposed retail building be supported on conventional spread
footing foundations bearing on medium dense native soil or 2 feet of properly compacted
native fill. The building floor slab and pavement can be similarly supported.
This report provides our geotechnical findings and recommendations for the project. These
recommendations should be incorporated into the project design and construction.
Servin�the Pacific'�orthwest
Main Office: 17522 Bothell Way NE,Bothell,VVA 98011
Tel(425) 415-d551 • Fax(425) 415-0311
. .
Geotechnical Engineerrng Report ii November 14, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-254
We trust the information presented is sufficient for your current needs. If you have any
questions or require additional information,please call.
Sincerely yours,
THE RILEY GROUP�INC.
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ExPiAEs SEPT. 12,w2�v �
Chien-Lin(Johnny) Chen, P.E. Ricky R. Wang, Ph.D., P.E.
Project Engineer Principal Engineer
JC/RW
The Riley Group, Inc.
TABLE OF CONTENTS
1.0 PROJECT DESCRIPTION..................................................................................... 1
2.0 SCOPE OF WORK................................................................................................... 1
3.0 SITE CONDITIONS.................................................................................................2
3.1 SURFACE.....................................................................................................................2
3.2 SOILS ..........................................................................................................................2
3.3 GROUNDWATER ..........................................................................................................2
3.4 SEiSMIC CONSIDERATIONS.......................................................................................... 2
4.0 DISCUSSION AND RECOMMENDATIONS.......................................................3
4.1 GENERAL .................................................................................................................... 3
4.2 SITE PREPARATION AND GRADING.............................................................................. 3
4.3 FOUNDATIONS.............................................................................................................4
4.4 SLAB-ON-GRADE CONSTRUCT[ON............................................................................... 4
4.S RETAINING WALLS ..................................................................................................... 5 '
4.E DRATNAGE AND STORMWATER FACILITY.................................................................... 5 '
4.� LITILITIES.................................................................................................................... 6
4.8 PAVEMENTS................................................................................................................ 6
5.0 ADDITIONAL SERVICES...................................................................................... �
6.0 LIMITATIONS.........................................................................................................7
LIST OF FIGURES
Figure1....................................................................................................................Site Vicinity Map
Figure 2..............................................................................................Geotechnical Exploration Plan
Figure 3............................................................................................Retaining Wall Drainage Detail
Figure 4.................................................................................................Typical Footing Drain Detail
LIST OF APPENDICES
Appendix.A....................................................................... Field Explof•ation and Laboratory Testing
The Riley Group, Inc.
• , Geotechnical Engineering Report 1 November 14, 2007
Proposed Walgreens Drugstore, Renton, W.4 Project#2007-254
1.0 PROJECT DESCRIPTION
The project site is located at 4105 and 4111 NE 4th Street in Renton, Washington. The
approximate location of the site is shown on the Site Vicinity Map, Figure 1. The site is
currently occupied by an abandoned Union 76 gas station and the Brown Bear car wash
with asphalt-paved parking lots around the buildings.
Riley understands that the existing buildings will be demolished and a Walgreens
drugstore building, approximately 14,800 square feet, will be constructed in the middle
portion of the site. Our understanding of the project is based on a preliminary site plan
prepared by Thomas Thompson, AIA dated October 8, 2007. At the time of preparing this
report, site grading and building plans were not available for us to review. Based on our
experience with similar construction, we anticipate that the proposed Walgreens building
will be a single-story structure supported on perimeter walls with a bearing load of 1 to 2
kips per linear foot, and a series of columns with a maximum load up to 75 kips.
The recommendations in the following sections of this report are based upon our
understanding of the above design features. If actual features vary or changes are made,
we should review them in order to modify our recommendations as required. In addition,
Riley requests to review final design drawings and specifications to verify that our project
understanding is correct and that our recommendations have been properly interpreted and
incorporated into project design and construction.
2.0 SCOPE OF WORK
On October 24, 2007, Riley drilled a total of seven test borings to a maximum depth of
20.5 feet below ground surface (bgs). Test borings were drilled with a truck-mounted,
hollow-stem auger drill rig. Test borings B-1, B-2 and TB-7 were drilled in the proposed
parking and driveway areas. Test borings B-3 through B-6 were drilled in the proposed
building footprint area. The approximate test boring locations are shown on Figure 2.
Using the information obtained from our subsurface exploration, we performed analyses to �
develop geotechnical recommendations for project design and construction on the
following:
i
➢ Soil and groundwater conditions ➢ Retaining Walls
➢ Seismic considerations ➢ Drainage and stormwater
➢ Site preparation and grading ➢ Utilities i
➢ Foundation support ➢ Pavements
➢ Slab-on-grade support
The Riley Group, Inc.
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Geotechnical Engineering Report 2 November 14, 2007
Proposed Walgreens Drugstore, Renlon, WA Project#2007-254
3.0 SITE CONDITIONS
3.1 Surface
The site is an L-shaped parcel of land approximately 1.14 acres in size. The site is bounded
to the north by NE 4�' Street, to the east by an undeveloped property, to the south by a Les
Schwab Tire Store and parking, and to the west by Union Avenue NE.
The site is currently occupied by an abandoned Union 76 gas station {#4105) on the
western portion of the site. The eastern of the site is occupied by the Brown Bear car wash
(#4111). The rest of the areas are asphalt-paved parking lots and driveways. The site gently
slopes down to the east with an overall elevation difference of 7 feet approximately.
3.2 Soils
The soils encountered in the test borings are relatively consistent across the site. The soil
profile includes 5 to 10 feet of fill overlying medium dense to very dense silty SAND with
gravel. The fill consists of loose to dense sandy GRAVEL to silty SAND with some gravel
and trace wood debris. The native soil is dense to very dense glacial till which consists of
silty sand with gravel.
Review of the Geologic Map of King County, Washington, by Vaughn E. Livingston Jr.
(1970) indicates that the soil in the project vicinity is mapped as Vashon till (Qt), which is
a haxd blue-gray concrete-like mixture of clay, silt, sand, and gravel. These descriptions are '�
similar to the native soil encountered during our field exploration.
More detailed descriptions of the subsurface conditions encountered are presented on the
Test Boring Log, Figures A-2 through A-8 in Appendix A.
3.3 Groundwater
Groundwater seepage was not encountered in any test borings reaching a maximum depth
of 20.5 feet bgs. The groundwater level seems to be deeper than the bottom of the test
boring termination depth.
Based on the soil condition, minor perched groundwater may be expected over the dense
layer during wet season. Fluctuations in groundwater level should be expected on a
seasonal and annual basis. The level will be highest during the extended periods of heavy
seepage in the wet winter months.
3.4 Seismic Considerations
Based on 2003 International Building Code (IBC), the site soil is Class D from Table
1615.1.1. The earthquake spectral response acceleration at short periods (SS) is 131%g and
at 1-second period (S�) is 46% g.
Liquefaction is a phenomenon where there is a reduction or complete loss of soil strength
due to an increase in water pressure induced by vibrations from a seismic event.
Liquefaction mainly affects geologically recent deposits of fine-grained sands that are
below the groundwater table. Soils of this nature derive their strength from intergranular
The Riley Group, Inc.
, ' Geotechnical Engineering Report 3 1Vovember 19, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-254
friction. The generated water pressure or pore pressure essentially separates the soil grains
and eliminates this intergranular friction, thus reducing or eliminating the soil's strength.
We reviewed the soil conditions encountered during field exploration and assessed the
potential for liquefaction of the site's soil during an earthquake. Since the soil below the
groundwater level is dense to very dense silty sand, Riley believes that the potential of soil
liquefaction during an earthquake event is low.
4.0 DISCUSSION AND RECOMMENDATIONS
4.1 General
Based on our study, the site is suitable for the proposed construction from a geotechnical
standpoint. The loose fill underlain the site is not suitable for directly supporting the
proposed building foundations and floor slab. If the loose fill is encountered below the
proposed footing subgrade, it should be properly compacted as structural fill. If the organic
soil encountered, it should be over-excavated and replaced with structural fill. The
proposed retail building can be supported on conventional spread footing foundations
bearing on at least medium dense native soil or 2 feet of properly compacted native fill.
The building floor slab and pavement can be similarly supported.
Detailed recommendations regarding the above issues and other geotechnical design
considerations are provided in the following sections. These recommendations should be
incorporated into the final design drawings and construction specifications.
4.2 Site Preparation and Gradin�
To prepare the site for construction, the existing buildings and pavements should be
demolished and stripped. Surface stripping depths of up to 6 inches should be expected to
remove the asphalt surface. All remnants related to previous construction, which occupied
the site, should also be cleared and removed from the site.
Once clearing and other preparing operations are complete, cuts and fills can be made to
establish desired parking grades. Prior to placing fill, we recommend proofrolling all
exposed surfaces to determine if any isolated loose and yielding areas are present.
Proofrolling should also be performed in cut areas that will provide direct support for new
construction.
The on-site excavated soils without organics are generally suitable for use as structural fill
if the moisture can be properly controlled. If the on-site soil or native fill will be used as
structural fill, it can be compacted onsite. The compaction should meet the general
structural fill compaction requirement. If the site grading requires additional structural fill,
we recommend importing a material that meets the grading requirements listed in Table 1.
Prior to use, a geotechnical engineer should examine and test all materials imported to the
site for use as structural fill. Structural fill materials should be placed in uniform loose
layers not exceeding 12 inches and compacted to a minimum of 95 percent of the soil's
The Riley Group, Inc.
, , Geotechnical Engineering Report 4 November 14, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-254
maximum density, as determined by ASTM Test Designation D-1557 (Modified Proctor).
The moisture content of the soil at the time of compaction should be within about two
percent of its optimum, as determined by this ASTM method.
Table l. Structural Fill
U.S. Sieve Size Percent Passin
3inches 100 ercent
No. 4 sieve 0 to 75 ercent
No. 200 sieve 0 to 5 ercent *
*Based on minus 3/4 inch fraction.
4.3 Foundations
Following the site preparation and grading, Riley recommends that the proposed building
foundations can be supported on conventional spread footings bearing on medium dense
native soil or 2 feet of compacted native fill. Perimeter foundations exposed to the weather
should be at a minimum depth of 18 inches below final exterior grades. Interior
foundations can be constructed at any convenient depth below the floor slab.
We recommend designing foundations for a net allowable bearing capacity of 2,500
pounds per square foot(ps�. For short-term loads, such as wind and seismic, a 1/3 increase
in this allowable capacity can be used.
For designing foundations to resist lateral loads, a base friction coefficient of 0.25 can be
used. Passive earth pressures acting on the side of the footing and buried portion of the
I foundation stem wall can also be considered for resisting lateral loads. We recommend '�
I calculating this lateral resistance using an equivalent fluid weight af 250 pounds per cubic
foot (pc�. At perimeter locations, we recommend not including the upper I2 inches of soil I
in this computation because they can be affected by weather or disturbed by future grading i
activity. This value assumes the foundation will be constructed neat against competent fill '
soil or backfilled with structural fill as described in the Site Preparation and Grading ',
section. The recommended friction and passive resistance values include a safety factor of '
1.5. �'
With spread footing foundations as recommended, you should expect maximum total and ��I
differential post-construction settlements of 1-inch and '/2-inch, respectively. j
4.4 Slab-on-Grade Construction �I
With site preparation completed as described in the Site Preparation and Grading section, I
suitable support for slab-on-grade construction should be provided. Riley recommends that
slab-on-grade construction be supported on firm native soil or on 12 inches of compacted
native fill. Immediately below the floor slab, we recommend placing a four-inch thick
capillary break layer of clean, free-draining sand or gravel that has less than 5% passing
The Riley Group, Inc.
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Geotechnical Engineer�i�7g Report S November 14, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-2�4
the No. 200 sieve. This material will reduce the potential for upward capillary movement
of water through the underlying soil and subsequent wetting of the floor slab.
Typically, an eight to ten-mil thick plastic membrane is placed on the capillary break to
avoid moisture by vapor transmission. The membrane should be covered with one to two
inches of clean, moist sand to guard against damage during construction and to aid in
curing of the concrete.
For the anticipated floor slab loading, we estimate post-construction floor settlements of'/4
to '/2 inch. For thickness design of the slab subjected to point loading from storage racks
and fork lift vehicle traffic, we recommend using a subgrade inodulus (Ks) of 100 pounds
per square inch per inch of deflection (pci}.
4.5 Retainin�Walls
At the time of preparation of this report, Riley is not aware of an;� ne«� retaining ���alls
proposed for the site. If retaining walls will be needed, they should be designed based on
the soil parameters provided below.
Riley recommends designing unrestrained walls for an active earth pressure imposed by an
equivalent fluid weighing 35 pcf. For restrained walls, an earth pressure imposed by an
equivalent fluid weighing 55 pcf should be used for design. For seismic design, an addition
uniform load af 5 to 7 H (H is wall height) should be applied to the wall surface. These
values assume a horizontal backfill condition without building or traffic surcharge loading
on the wall.
The walls must also be provided with adequate drainage and should be waterproofed. A
typical retaining wall drainage detail is shown on Figure 3.
4.6 Draina�e and Stormwater Facility
Surface
Final exterior grades should promote free and positive drainage away from building. Water
must not pond or collect adjacent to foundations or within the immediate building area. We
recommend providing a minimum drainage gradient of 3% for a minimum distance of ten
feet from the building perimeter, except in paved locations. In paved locations, a minimum
gradient of 1% should be provided unless provisions are included for collection and
disposal of surface water adjacent the structure.
Subsurface
We recommend installing perimeter foundation drains. A typical recommended drain detail
is shown on Figure 4. The foundation drains and roof downspouts should be tightlined
separately to an approved discharge facility. Subsurface drains must be laid with a gradient
sufficient to promote positive flow to a controlled point of approved discharge.
The Riley Group, Inc.
' Geotechnical Engineering Report 6 November J4, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-254
4.7 Utilities
Utility pipes should be bedded and backfilled in accordance with American Public Works
Association (APWA) specifications. For site utilities located within the City of Renton
right-of-ways, bedding and backfill should be completed in accordance with City of
Renton specifications. As a minimum, trench backfill should be placed and compacted as
structural fill, as described in the Site Preparation and Grading section.
Where utilities occur below unimproved areas, the degree of compaction can be reduced to
a minimum of 90 percent of the soil's maximum density as determined by the referenced
ASTM standard. As noted, soils excavated on-site will be suitable for use as backfill
material if the soil's moisture can be properly controlled. The backfill material should
satisfy the structural fill requirements listed in the Site Preparation and Grading section.
4.8 Pavements
Pavement subgrades should be prepared as described in the Site Preparation and Grading
section of this report and as discussed below. Regardless of the relative compaction
achieved, the subgrade must be firm and relatively unyielding before paving. The subgrade
should consist of firm native soil ar properly compacted native fill. The condition should
be verified by a geotechnical engineer during construction.
With the pavement subgrade prepared as described above, we recommend that the general
parking area be paved with flexible pavement surface. The following pavement sections
are recommended:
➢ For heavy truck traffic areas: 4 inches of asphalt concrete (AC) over 6 inches of
crushed rock base (CRB) over 18 inches of compacted native fill; and
➢ For general parking areas: 3 inches of AC over 4 inches of CRB over 12 inches
of compacted native fill.
The asphalt paving materials used should conform to the Washington State Department of
Transportation (WSDOT) specifications for Class B asphalt concrete and CRB surfacing.
Long-term pavement performance will depend on surface drainage. A poorly-drained
pavement section will be subject to premature failure as a result of surface water
infiltrating into the subgrade soils and reducing their supporting capability.
For optimum pavement performance, surface drainage gradients of no less than two
percent are recommended. Also, some degree of longitudinal and transverse cracking of
the pavement surface should be expected over time. Regular maintenance should be
planned to seal cracks when they occur.
The Riley Group, Inc.
Geolechnical Engineeriiag Report ? Noventber 14, ?007
Proposed Walgreens D��ugstore, Renton, W.4 Project#2007-2�4
5.0 ADDITIONAL SERVICES
Riley is available to provide further geotechnical consultation as the project design
develops. Riley should review the final design and specifications in order to verify that
earthwork and foundation recommendations have been properly interpreted and
incorporated into project design and construction.
Riley is also available to provide geotechnical engineering and monitoring services during
construction. The integrity of the foundation depends on proper site preparation and
construction proccdures. In addition, engineering decisions may ha�e to be made in the
field in the event that variations in subsurface conditions become apparent. Construction
monitoring services are not part of this scope of work. If these services are desired, please
let us know and we will prepare a cost proposal.
6.0 LIMITATIONS
This report is the property of The Riley Group, Inc. and Phillips Edison & Company, and
was prepared in accordance with generally accepted geotechnical engineering practices.
This report is intended for specific application to the Proposed Walgreens Drugstore at
4105 and 4111 NE street in Renton, Washington, and for the exclusive use of Phillips
Edison & Company and its authorized representatives. 1�'0 other warranty, expresscd or
implied, is made.
The analyses and recommendations presented in this report are based upon data obtained
from the test borings drilled on-site. Variations in soil conditions can occur, the nature and
extent of which may not become evident until construction. If variations appear evident,
The Riley Group, Inc. should be requested to reevaluate the recommendations in this report
prior to proceeding with canstruction.
The Riley Group, Inc.
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Reference:
Figure modified from site plan prepared by Thomas Thompson,AIA dated October 8,2007. N
� Geotechnical fest boring location drilled by The Riley Group, DRAWING NOT TO SCALE
g�1 Inc. on October 24, 2007.
P�oposed Walgreens Drugstore
� The Riley Group, Inc.
1�s22 BOT�LL wAY NE Geotechnical Explo�-atiotz Plan Figure 2
BOTHELL,WASHINGT�ON 98011
Site Address: 4105&4111 NE 4th Sti-eet,Renton,Washington
12° MINIMUM WIDE �--
FREE-ORAINING GRAVEL
SLOPE TO DRAIN
� '
�.
.. � � �
. � _ . �_
�
,
0
12" MIN. � �� . _ � . . . : . . . � . . . . . .... � -
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,00 .. . . i•
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o�� . �,
,o
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ao _
a e° : : � �
FILTER FABRIC MATERIAL �o° � .� � � -
00 . , EXCAVATED SLOPE
'° � � � � � (SEE REPORT FOR
o g � :. � � . � ; � APPROPRIATE
�o � . �. � . , INCLINATIONS)
o;� . � � . � r�� COMPACTED STRUCTURAL
�a, . � � - BACKFILL (NATIVE OR
�° IMPORT)
00 . �
a
e°o�
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\;� r. i, .: i,: :: i. �.� . . ' 12" OVER THE PIPE
�� � 3" BELOW THE PIPE
4 DIAMETER PVC
PERFORATED PIPE
N OT T 0 SCALE
' The Riley Group, Inc. Proposed Walgreens Drugstore
17522 BOTHELL WAY NE Retaining Wall Drainage Detail Figure 3
BOTHELL,WASHINGTON 98011
Site Address:4105&4111 NE 4th Street,Renton,Washington
BUILDING SLAB
i
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` 8
. .
° ' ° . `..\��\��\��\�i
: , • . . .
• .
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• . � 'STRUCTURAIl:
\ ' �.
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. ' ,��
a
� • � - � FILTER
.
� i FABRIC
\ . . . - - ��� .
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a �
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/� /� /� /� /� /� /� /� / �/
4"PERFORATED PIPE
3/4"WASHED ROCK OR PEA GRAVEL
NOT TO SCALE
Proposed Walgreens Drugstore
�� The Riley Group, Inc.
17522 BOTHELL WAY NE Typical Footing Drain Detail Figure 4
BOTHELL,WASHINGTON 98011
Site Address:4105 &4111 NE 4th Sh•eet,Renton,Washington
+ , Geotechnical Engineering Report November 14, 2007
Proposed Walgreens Drugstore, Renton, WA Project#2007-254
APPENDIX A
FIELD EXPLORATION AND LABORATORY TESTING
Proposed Walgreens Drugstore
4105 &4111 NE 4`h Street
Renton, WA 98059
On October 24, 2007, we performed our field exploration using a truck-mounted drill rig.
We explored subsurface soil conditions at the site by advancing seven test borings to a
maximum depth of 20.5 feet below existing grade. The test boring locations are shown on
Figure 2. The test boring locations were approximately determined by measurements from
existing property lines and paved roads. The Test Boring Logs are presented on Figures A-
2 through A-9.
A geologist/engineer from our office conducted the field exploration and classified the soil
conditions encountered, maintained a log of each test boring, obtained representative soil
samples, and observed pertinent site features. All soil samples were visually classified in
accordance with the Unified Soil Classification System (USCS) described on Figure A-1.
Representative soil samples obtained from the test borings were placed in closed
containers and taken to our laboratory for further examination and testing. The moisture
content of typical sample was measured and is reported on the Test Boring Logs.
The Riley Group, Inc.
MAJOR DIVISIONS LETTER TYPICAL DESCRIPTION
SYMBOL
e -gra e grave s, grave-san mi ures, i e
� GRAVELS GRAVELS GW or no fines.
� `- More than 50% � o Poorly-graded gravels, gravel-sand mixtures,
W � 5 /o fines GP little or no fines.
Z � of coarse Silty gravels, gravel-sand-silt mixtures,
Q � � fraction is larger GRAVELS GM non- lastic fines.
� J � .� than No. 4 sieve with fines GC Clayey gravels, gravel-sand-clay mixtures,
lastic fines.
� � o Well-graded sands, gravelly sands, little or no
� � � N SAN DS CLEAN S�/ fines.
� � Z More than 50% SANDS Poorly-graded sands or gravelly sands, little or
Q � of coarse �5% fines SP no fines.
O `�
U � fraction is SANDS SM Silty sands, sand-silt mixtures, non-plasticfines.
o smaller than No. With fines
� 4 sieve SC Clayey sands, sand-clay mixtures, plastic fines.
� norganic si s, roc our, c ayey si s wi s ig
� •`�—� ���—' S I LTS AN D CLAYS M� plasticity.
W a� N norganic c ays o ow o me ium p as ici , ean
Z E o Liquid limits CL clay).
Q (n o "' less than 50%
� J � Z QL Organic silts and organic clays of low plasticity.
— o
� � c � MH Inorganic silts, elastic.
`° SILTS AND CLAYS
W � � �
z � � Liquid limits greater CH Inorganic clays of high plasticity, (fat clays).
� � E than 50%
� �H Organic clays of high plasticity.
HIGHLY ORGANIC SOILS PT Peat.
DEFINITION OF TERMS AND SYMBOLS
O J �Very loase SPT (Bloo�s/Foot) � 2° Outside diameter split spoon
p j Loose 4-10 sampler
Z Q Medium dense 10-30 2.4" Inside diameter ring sampler or
Q � Dense 30-50 � Shelby tube
� � Very dense >50 � Water level (date)
Consistency SPT{Blows/Foot) Tr Torvane reading, tsf
L Very soft 0-2 pp Penetrometer reading, tsf
� � Soft 2-4 DD Dry density, pcf ��
� J Medium stiff 4-8 �� Liquid limit, percent �
� V Stiff 8-15 p� Plasticity index
Very stiff 15-30 N Standard penetration, blows per foot
Hard >30
Proposed Walgreens Drugstore
� Tlze Riley Group, Inc.
17522 BOTHELL WAY NE Unified Soil Classification System Figure A-1
BOTHELL,WASHINGTON 98011
Site Address:4105&41 l 1 NE 4th Street,Renton,Washington
V •
Boring No. B-1
Logged by : PL
Date: 10/24/07 Approximate Elev.: N/A
Consistency/ Q (N) Moisture
Soil Description Relative Depth � Blows Content
Density (feet) � /ft (°/a)
Surface: Asphalt- 3".
CRB down to 3.8'. Medium --
(Crushed Rock Base) Dense - � 12 3.1
5 T
Brown silty SAND with some 1 4 10.5
gravel, dry to damp, loose, Loose
(Fill).
I 4 9.8
Mottfed Brownish gray silty Medium 10
SAND with gravel, damp, Dense I 21 10.1
medium dense, (SM}. --
Terminated at 11.5'.
No groundwater seepage
encountered. - 15
I
-- 20
�� The Riley GYoup, Inc. Proposed Walgreens Drugstore
17522 BOTHELL WAY NE Test Boring Log B-1 Figure A-2
BOTHELL,WASHINGTON 98011
Site Address:4105 &4111 NE 4th Street,Renton,Washington
i 4
Boring No. B-2
Logged by : PL ;
' Date: 10/24/07 Approximate Elev.: N/A
Consistency/ Q (N) Moisture
Soil Description Relative Depth � Blows Content
Density (feet) � �ft �o�o�
SurFace: Asphalt - 1.5".
Brown sandy GRAVEL with
cobbles, trace silt, damp, Dense -
dense, (Fill).
5
Mottled Grayish brown silty Very Dense I 89�9�� 5.a
SAND with gravel, damp, very
dense, (SM).
Terminated at 6.5' at refusal.
No groundwater seepage -- 10
encountered. -
- 15
20
� Tlze Riley GYoup, Inc. Proposed Walgreens Drugstore
17522 BOTHELL WAY NE Test Boring Log B-2 Figure A-3
BOTHELL,WASHiNGTON 9801 I
Site Address: 4105 &4111 NE 4th Street,Renton,Washington
, .
Boring No. B-3
Logged by : PL �
Date: 10/24/07 Approximate Elev.: NIA
Consistency/ °' {N) Moisture
Soil Description Relative Depth � glows Content
Density (feet} � �ft �a/a�
Surface: Asphalt - 1.5". __
Brown silty SAND with gravel,
trace silt, turning black at tip,
damp, loose, (Fill).
Loose 5
I 6 �.�
Black silty SAND with wood
debris{charred), damp, loose, -
(Fill). Loose _ 10 T
_ 1 6 34.7
Mottled reddish brown silty Loose
SAND with gravel, damp, to -
loose to dense, (SM). Dense --
15 T
-- 1 50/3" 8.7
Gray silty SAND with gravel, Very Dense
damp, very dense, (SM).
20 1 50/3" 10.0
Terminated at 20.5'.
No groundwater seepage
encountered. -
� The Riley Group, Inc. Pf•oposed Walgreens Df-ugstore
17522 BOTHELL WAY NE Test Boring Log B-3 Figure A-4
BOTHELL,WASHINGTON 9801 I
Site Address: 4105&4111 NE 4th Street,Renton,Washington
f , /
Boring No. B-4
Logged by : PL
Date: 10/24/07 Approximate Elev.: NlA
Consistency/ � (N} Moisture
Soil Description Relative Depth � Blows Content
Density (feet) � �ft (%)
Surface: Asphalt - 1.5".
Light brown silty SAND with Loose -
gravel, damp, loose #o medium to
dense, (Fill). Medium Dense
5
I 50/4" 5.9
Gray silty SAND with gravel,
damp, very dense, {SM). Very Dense T
- 1 50/3" 7.5
10
Terminated at 9.0' at refusal.
No groundwater seepage
encountered.
15
20
� The Riley Group, Irt�. P�"oposed Walgpeens Drugstore
17522 BOTHELL WAY NE Test Boring Log B-4 Figure A-S
BOTHELL,WASHINGTON 9801 I
Site Address:4105&4111 NE 4th Street,Renton,Washington
1 � !
Boring No, B-5
Logged by : PL
Date: 10/24/07 Approximate Elev.: N/A
Consistency/ a (N) Moisture I
Soil Description Relative Depth � Blows Content '
Density (feet) � /ft �%}
Surface: Asphalt - 2.0". ,
Brown sifty SAND with gravel,
damp, loose, {Fill). Loose
- 5
Loose � g 15.2
Gray silty SAND with trace to
some gravel, damp, loose to to -
medium dense, (Fill).
Medium
Dense
-- 10 T
_ 1 11 15.4 ,
Brown silty SAND with gravel, ,
dam ve dense, SM . Very Dense
P� rY � ) 50/4" 8.0 II
Terminated at 14.0' at refusal. -- 1' i
No groundwater seepage --
encountered. _
20
�' The Riley Group, Inc. 1'roposed Walgreens Drugstore
17522 BOTHELL WAY NE Test Boring Log B-S Figure A-6
BOTHELL,WASHINGTON 98011
Site Address: 4105&4111 NE 4th Street,Renton,Washington '
�, � J
J
Boring No. B-6
Logged by : PL
Date: 10/24/07 Approximate Elev.: N/A
Consistency/ Q (N) Moisture
Soil Description Relative Depth � Blows Content
Density (feet) � �ft �%�
Surface: Asphalt - 2.0".
Brown silty SAND with gravel, __
damp, loose, (Fill). Loose
-- 5
Loose _ � g 8.1
Grayish brown SAND with to
some gravel, some silt, damp,
loose, (Fill}.
Medium
Dense _ 10
_ � 10 11.0
Gray silty SAND with gravel,
damp, dense, (SM). Dense
- 15
I 36 7.$
Terminated at 16.5'.
No groundwater seepage
encountered. --
- 20
� The Riley Group, If2�. P�"ol�osed Walgreens Drugstore
17522 BOTHELL WAY NE Test Boring�og B-6 Figure A-7
BOTFIELL,WASHINGTON 98011
Site Address: 4105 &4111 NE 4th Street,Renton,Washington
� . . �..
Boring No. B-7
Logged by : PL
Date: 10/24/07 Approximate Elev.: N!A
Consistency/ �' (N) Moisture
Relative De th �"
Soil Description P E Blows Content
Density (feet) � �ft �o�o�
SurFace: Asphalt - 3_5".
Gray silty SAND with gravel, Dense - �
damp, dense, (Fill). 27 $•9
_ 5
Brown to gray silty SAND with I 11 12.2
some gravel, damp, medium Medium
dense, (SM). Dense
� 14 9.5
Terminated at 9.0'. 10
No groundwater seepage '
encountered. '
15 ;
20
�� The Riley Gaoup, Inc. �'�'oposed Walgreens Drugstore ,
17522 BOTHELL WAY NE Test Boring Log B-7 Figure A-8 i,
BOTHELL,WASHINGTON 98011 i
Site Address:4105 &4111 NE 4th Street,Renton,Washington i