HomeMy WebLinkAbout03231 - Technical Information Report - Geotechnical;� , �- 323 �
� �
-'��� �I�-�� ���,.,. �.-� � ���_ � f ,��� �_ -��
�k ' Bergquist Engineering Services
�� 27207 8th Avenue S PO. Box 13309
� �
Des Moines, Washington 98198 Des Moines, Washington 98198
Phone: 253.941 ,9399, Fax: 253.941 ,9499, e-mail: RBergqu510@aol.com
t� February 14, 2004
: ►
Mr. Terry Defoor
� � GWC, IC1C. DEVELOPMENT PLANNiNG
CITY OF RENTON
'� 24633 NE 133'� Street
,�, Duvall, Washingbn 98019 MAR 0 5 2004
' Re: Geotechnical Engineering Services RECEIVED
� , Proposed Jericho Plat Subdivision
Southwest of the Intersection of NE 4�' Street and 144�' Avenue SE
� ' Renton, Washington
� BES Project Number: 200402, Report 1
Dear Mr. Defoor:
Bergquist Engineering Services is pleased to provide this report of the geotechnical
, exploration and engineering analysis for the referenced project. The attached report
summarizes project and site data, describes the services we perFormed, presents our findings,
and provides recommendations regarding design of the foundations, laterai earth pressures,
drainage, and earthwork. The appendix presents site maps, test pit logs, and explanatory
aids.
� � We appreciate the opportunity to be of service to you. If you have any questions
� concerning this report, or if we may be of further service, please contact us.
,
� p,. B��'
`,�+~�O�WAS�I,�,� Sincerely,
i , �' � ,-a��'� co ���`' Be�gquist Engineering Services
. `r .2s/!¢ .O�
� ,c� �r ��
, .�o � 3�� _ ;
�`rSf�NAL��'�v. -
Richard A. Bergq ist, P.E.
�xP��Es p Principal
Copies to: Terry Defoor (1 telefaxed)
Terry Defoor (3 mailed)
Jim Jaeger (2 mailed)
GEOTECNNICAL ENGfNEERING AND CONSTRUCT�aN INSPFCTJON
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� i TABLE OF CONTENTS ,
�� l . INTRODUCTION ................ 1 '
, ....................................................................................
' ; 2. PROJECT DESCRIPTION ......................................................................................... 2
'T 3. SCOPE OF SERVICES
.............................................................................................. 2
" 4. SITE CHARACTERIZATION 3
......................................................................................
t� 4.1 Site Classification................................... .............. 3
. ...........................................
ii
4.2 Surface........................................................................................................... 3
�� 4.3 Subsurface Soif and Groundwater ........ 3
...........................................�-•-�--•-----...
' ' S. DISCUSSION
.......................................................................................................... 4
" 6. RECOMMENDATIONS.....................•--.................
................................................... 4
`j 6.1 Seismic Considerations
................................................................................... 5
�' 6.2 Founda#ions
........................�--..................................._.........---........................ 5
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6.3 Slabs-on-Grade...................•---....................................................................... 6
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t b.4 Earthwork....................................................................................................... 6
k ` 6.4.1 Site Clearing
.................................................................................•-- 6
�' 6.4.2 Excavation
� ........................................................................................ 6
� j 6.4.3 Foundation Preparation
..................................................................... 7
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6.4.4 Slab-on-Grade Preparation ............................................................... 7
6.4.5 Materials .......................................................................................... 7
6.4.6 Placement and Compac#ion .............................................................. 8
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6.5 Drainage....................................................................•-•................•--.............. 9
' 6.6 Groundwater.................................................................................................. 9
6.7 Erosion.......................•-•....••••......................................................................... 9 I
„
6.8 Construdion Observation and Testing ............................................................ 10
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7. REPORT LIMITATIONS............................................................................................ 10
APPENDIX I
VicinityMap ............................................................................................................. Al I�
SitePlctn ............................................................................................................. A2
TestPit Logs ............................................................................................................. A3 �
TestPit log �lo#es--------------------------------------------------------��--�--------�--�--------�--��--�-------------... A7 I
Unified Soil Classification System................................................................................... A9
Schematic of Footing Drain...........•••........................................................................... Al 0 i
Notes ............................................................................................................ A11
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� 1 GEOTECHNICAL EXPLORATION
�� and ENGINEERING EVALUATION
PROPOSED SUBDIVISION
JERICHO PLAT
�T
i�
PLUS 5-ACRE SITE SOUTHVI/EST of the INTERSECTION of
NE 4T" STREET and 144T" AVENUE SE
�� RENTON,WASHINGTON
' � KING COUNTY PARCEL NUMBERS: 1523059045, 1523059019,
r� 1523059047, 1523059148, and1523059033
, prepared for:
GWC, INC.
by:
BERGQUIST ENGINEERING SERVICES
` BES PROJECT NUMBER: 200402-REPORT 1
� FEBRUARY 14, 2004 !
1. INTRODUCTION
This report presents the results of our geotechnical exploration for the proposed subdivision
southwest of the intersection of NE 4�' Street and 144�' Avenue SE in Renton, Washington.
The location of the site is shown on the �cinity Map on page A1 in the Appendix of this
report. The geotechnical exploration was performed by Bergquist Engineering Services (BES)
to provide information or recommendations regarding:
• seismic design considerations including liquefaction potential,
• allowable bearing capacity and depth of suitable foundation systems with
estimated settlements,
• lateral earfh pressures and friction coefficients,
• influence of groundwater on the development,
• drainage,
• site preparation, earthwork, and excavation-slope considerations.
��
= 1 Proposed Subdivision (Jericho Plat) February 14, 2004
Renton, Washington BES Project Number 200402,-Report 1
�� .
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Mr. Terry Defoor of GWC, Inc. authorized our work on January 23, 2004, by signing and
�� returning a copy of BES Proposal Number 1022004, dated January 22, 2004.
il
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�� 2. PROJECT DESCRIPTION
��( The project involves design and development of the roughly 5.33-acre site into roughl 36,:
single-family, residential lots. The buildings will be constructed with their lowest floor
�� elevation at or near current site grades. A below-grade, stormwater vault may be
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constructed.
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{� Actual foundation loads were not provided at the time this reporf was prepared. Therefore,
t� we have assumed that individual column loads will not exceed 100 kips and continuous wall
i� loads will not exceed 4 kips per lineal foot. If the actual foundafiion loads are greater than
„ those stated herein, the geotechnical engineer must be notified to determine whether the
recommendations presented herein require revision.
; �
3. SCOPE OF SERVICES
' ` The scope of services included a reconnaissance of the site by the geotechnical engineer, a
�� review of geologic literature, logging and sampling seven (7) test pits, laboratory testing,
� engineering analysis, and preparation of fihis report. Soil samples were taken at the intervals
_ noted on the individual test pit logs, which are presented in the Appendix on pages A3, A4,
A5, and A6. Upon completion, the test pits were backfilled with the excavated site-soils.
The soil samples were returned fio our laboratory for analysis, which included visual
classification and determination of the natural moisture content of selected samples. The
field and laboratory data were then evaluated by the geotechnicai engineer relative to the
proposed construction. The engineering recommendations and advice presented in this
report have been made in accordance with generally accepted geotechnical-engineering
practices in the area.
Bergquist Engineering Services Page 2 of 10
T� .
,. Proposed Subdivision (Jericho Plat) February 14, 2004
Renton, Washington BES Project Number 200402,-Report 1
1�
4. SITE CHARACTERIZATION
'1
' � The information presented in this section was gathered by BES personnel for geofiechnical
� engineering purposes only. This site characterization was not intended to address the
i j presence or likelihood of contamination on or around the site. Specialized methods and
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procedures, which were not a parf of this scope of services, are required for an adequate
;j environmental site assessment.
�� 4.1 Site Classificafiion
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According to Plate 7 Generalized Geo%Qic M� of Seattle and Suburban Areas by Galster,
" R. W., and Laprde, W.T., 1991, the site soils are comprised of undifferentiated Pleistocene
`� glacial and nonglacial deposits including Vashon Stade drift and outwash deposits.
i► Extrapolation of the Preliminary Liquefacfion Suscepiibilify Map of the Renton Quodrong/e,
� ► Washington by Stephen P. Palmer, the soils at this site are not susceptible to liquefaction.
, ? Additionally, based on the soil classification and density as determined by the test pits, the
soils at this site are not susceptible to liquefaction.
4.2 Surface
� � At the time of our exploration, the site was predominantly covered with dormant vegetation
� ' consisting blackberry, scotch broom, a few apple trees, and weeds. There was an occupied
" house and an out-building in the northeast corner and an un-occupied house with severa{
�- out-buildings (sheds) near the northwest and southwest corners of the site.
The ground surface generally sloped down from a high elevation of 442 feet along the east
�
side of the site to a low elevation of 424 along the west side of the site. There was a
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depression with wet surface soils near the southwest corner of the site.
4.3 Subsur-face Soil and Groundwater
The subsurface soil and groundwater conditions at this site are described in the following
paragraphs and are presented graphically on the test pit iogs in the Appendix of this report.
The stratification lines, indicated on the test pit logs, represent the approximate boundaries
between soil types. Actual boundaries may be gradual and the firansitions may not be easily
discemible during site excavation. I
Bergquist Engineering Services Page 3 of 10
T
,� Proposed $ubdivision (Jericho Plat} February 14, 2004
Renton, Washington BES Project Number 2004Q2,-Report 1
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In general, the site is covered with a four- to six-inch thick layer of topsoil consisting of dark
� brown, loose Sandy SILT (ML,) trace gravel and roots. Underlying the topsoil, reddish-brown,
� loose to medium dense SAND-SILT (SM), with gravel and occasional cobble was encountered
�� to a depth of about two to three feet be�ow the surface. This layer is interpretec! as weathered
1 � till and considered not suitable for support of foundations, roads, or slabs-on-grade.
�1 Underlying the weathered till, (ight brown to light gray and gray, medium dense to dense or
�j hard SAND-SILT (SMj with gravel, trace cobble was encountered to the termination depth of
the test pit. This deposit is interpreted as un-weathered glacial till and may contain varying
« amounts of gravel, cobbles, or even large boulders. The un-weathered glacial till is suitable
, ►
for support of building foundations, roads, and slabs-on-grade.
..
il Test Pit 4 was terminated in wet SILT (ML) that may have been a drain field for a septic � '
�r system. It is anticipated that some over-excavation may be required in this area. � �
� ;
�r Groundwater was encountered in Test Pits 4, 5, and 6 in the form of seepage above the
denser till. Therefore, the seepage water is considered perched stormwater trapped in the
upper, loose soils.
5. DISCUSSION
►:
": The recommendations presented in this report are based on our understanding of the project
' ` as presented in the Project Description Section and on the assumption that the subsurface
�� conditions encountered in the test pits adequately represent conditions near and between the
. , exploratory test pits. Because project conditions regarding type and location of structures and
_ foundation loads can change and because subsurface conditions are not always similar to
those encountered in the test pits, the geotechnical engineer must be contacted for review
and possible revision of the recommendations if discrepancies are noticed.
6. RECOMMENDATIONS
The following sections present recommendations regarding seismic considerations,
foundations, lateral earth pressures, and for earthwork, excavations, drainage, and
groundwater.
Bergquist Engineering Services Page 4 of 10
� � Proposed Subdivision (Jericho Plat) February ]4,2004
Renton, Washington BES Project Num6er 200402,-Report 1
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6.1 Seismic Considerations
�� According to Figure No. 16-2 of the 1997 Uniform Building CodeT'" {UBC), the project site is
'j in Seismic Zone 3. According to Table 16-J of the UBC, the soil profile at this site is best
4� represented by a "Soil Profile Type Sp" (StifF Soil). The site soils are not susceptible to
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liquefaction and therefore exhibit minimum seismic risk.
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6.2 Foundations
�� Canventional spread footing foundations may be used to support the proposed structures.
•� Spread footing (continuous wall and individual column) foundations may be dimensioned
,j using a net allowable bearing capacity of up to 2,000 psf if they are placed in the
;; undisturbed, light brown, brown, or gray, medium dense, dense, or hard SAND-S1LT (SM)
encountered at a depth of about 24 to 36 inches below the existing ground surface of the
iT
SIt2.
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" The recommended minimum dimension for continuous wall footings is 18 inches and for
' �j individual column footings, the recommended minimum dimension is 24 inches. All
f? perimeter footings must be placed at least 18 inches below finished grade for frost protection.
�� The allowable bearing capacities may be increased by one-third for wind and seismic loads.
' ,. If the recommendations in this report are followed, total seltlement of the foundation will be
« less than one inch (1 inch) with differential seitlements of less than three-quarters of an inch
��
(3/a inch.)
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Lateral earth pressures for design of foundations, detention v4ult walls, or short retaining
� walls with level backfill and without hydrostatic pressures or surcharge loads, may be �I
` calculated using the equivalent fluid pressures presented below: '
Active: Undisturbed subsoils 40 psf/ft.
� Compacted granular soils 35 psf/ft.
Passive: Continuous footings 250 psf/ft.
Column footings 300 psf/ft.
At-Rest Detention Vault Walls 65 psf/ft
Bergquist Engineering Services Page 5 of 10
' ? .
, � Proposed Subdivision (Jericho Plat) February 14, 2004
Renton, Washington BES Project Number 200402,-Report 1
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A coefFicient of friction between footings and bearing soils of 0.35 may be used to resist
�� lateral foundation loads. If passive earth pressures are used in conjunction with base friction
i� to resist latera) loads, reduce the ultimate coefficient of friction to 0.30.
r� Footings, stem walls, and retaining walls must be reinforced to reduce the potenfiial for
; ;
distress caused by differential foundation movements. A qualified engineer must determine
�� the size, quantity, and location of reinforcement. AI1 footing excavations at this site must be
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inspected by the geotechnical engineer prior to placement of construction forms and
(� reinforcement steel.
��
, 6.3 Slabs-on-Grade
'� Slabs-on-grade must be supported on a minimum four-inch thick, free-draining sand or
gravel base fihat follows gradation and compaction recommendations provided in Table 6.1
�� of this report. All concrete, especially slabs-on-grade, should be placed at minimum water-
`' cement rafios on moistened surfaces and properly cured to minimize shrinkage, cracking,
�� warping, and curling. Concrete slabs should be allowed to cure adequately before
. subjecting them to full design loads. Any concrete that will be exposed fio the elements
, should be entrained with four to six percent air to minimize damage from freeze-thaw cycles
�
Polyethyfene sheeting must be carefully piaced on the granular base to act as a vapor
'' retarder between the concrete and soil. A two- to four-inch thick layer of sand maybe placed
' over the polyethylene sheeting to improve concrete curing and fio protect fihe sheefiing from
� damage during placement of the slab elements. If provided, floor coverings must not be
t placed until the concrete floor has cured sufficiently.
-- 6.4 Earthwork
The recommendations presented in this reporf are predicated on fulfillment of the following
earthwork recommendations.
- -- 6.4.1 Sifie Clearing: Strip and remove any topsoil, tree stumps, weeds, old rubble fill, and
other deleterious materials from the project area prior to construction. After site clearing, the
exposed surface must be graded relatively flat fio allow for proper subgrade prepara#ion but
sloped slightly to allow good surface drainage during construction.
— 6.4.2 Excavation: Conventional-excavating equipmenfi should be suitab�e for the proposed
shallow foundation excavations. Use excavating buckets without teeth to excavate af I
Bergquist Engineering Services Page 6 of 10
, � Proposed Subdivision (Jericho Plat) February ]4, 2004
Renton, Washington BES Project Number 200402,-Report 1
�� '
� ` foundations so as not to disturb the bearing surfaces. Shallow excavations {less than three
►� feet in depth) will stand open with vertical side slopes for short durations: however, according
� � to Chapter 296-155, Parf N of the Safefy Standards for Consfrucfion Work in the State of
�� WashinQton, the site soils classify as Type C. Therefore, side slopes of excavations deeper
�j than four (4� feet must be no steeper than one and one-half (1 .5) horizontal to one {1 j
verfical (1 .5H:1 V). If the dimensions of the site prevent the use of maximum slopes of
r� 1 _5H:1V, the slopes must be stabilized or shored to facilitate safe excavations. The
� geotechnical engineer must be contacted for additional recommendations if such techniques
�� are going to be employed.
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!� 6.4.3 Foundation Preparation: Specialized treatment of the foundation soils is not
�j anticipated at this site if the foundations are placed in the un-weathered glacial till. The
,z excavations, however, must be made carefully using a backhoe bucket without teeth so as not
;, to disturb the bearing soils. If loose or soft soils are encountered at the footing elevation,
they must be removed and rep{aced with properly compacted backfill as described in Sections
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6.4.5 and 6.4.6 of this report.
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�? b.4.4 Slab-on-Grade Preparation: If the earthwork recommendations provided in this
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' ' report are followed, specialized treatment of the soil beneath slabs-on-grade at this site is not
� generally expected to be necessary. However, if any debris, organic material, organic fill
� � sails, loose soils, or other deleterious materials are encountered at the subgrade elevation
they must be removed and replaced with structural backfill.
-� 6.4.5 Materials: The on-site topsoil and SAND-SILT (SM) soils are not suifiable for use as
structural fill or backfill. The organic-rich soils must only be used in landscape or non-
structural areas. Site SAND-SILT (SM) soils are considered not to be all-weather soils and
should be worked only during the dry season.
If additional soil is needed for sfiructural fill or backfill to meet design grades, it must be
imported and conform to the gradation presented in Table 6.1 , and be approved by the
geotechnical engineer prior to use. Samples must be submit�ed to the geotechnical engineer
at feast 72 hours before approval is required and before the materials are used.
Bergquist Engineering Services Page 7 of 10
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' ` �
;� Proposed Subdivision {Jericho Plat) February 14,2004
Renton,Wcuhington BES Project Number 200402,-Report ]
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Gravel base and select materials for pavement subgrade must conform to local govemmentai
�� standards, such as City of Renton, King County, or other suitable specifications approved by
` � fihe geotechnical engineer.
��
TABLE b.l GRADATION REQUlREMENTS FOR STRUCTURAL �ILL
U.S. Standard Sieve � t'ercenf Passing -
j i
3-inch l OQ ,
� 3/4-inch 50-100 I,
�j No. 4 25-65 ,
� No. 10 10-50 '�
, i�to. 40 0-20 '
No. 200 0-5*
*Note: The percent passing the No. 200 sieve is based on the ,
weight of the material passing the 3/4-inch sieve.
� 1f construction is performed during the wet season, a granular base or work blanket will be
required. Granular materials used as a work blanket should conform to the gradation t
presented in Table 6.2, and be approved by the geo#echnical engineer prior to use. �
�� ��
TAa�.� 6.2 GRADATION REQUIREMENTS FOR WORK BLANKET
� _ „�� ` '� , � � � � �
.a`�,���'�n���1�'€� � ::5�� �I`� Sp.v�1�e3��i1s73� } .:15`�.
4-inch 100
No. 200 5 maximum*
*1`lote: The percent passing fhe No. 200 sieve is based on the
weight of the material passing the 3/4-inch sieve.
b.4.6 Placement and Compaction: Structural fill and s#ructural backfil) must be placed in
relatively horizontal loose lifts no# exceeding ten (10) inches in fihickness and compacted to a#
least 95 percent of the modified Proctor (ASTM D1557� maximum density at moisture
contents wifihin two (2) percent of optimum. Bacicfill against detention vault walls must be
carefully compacted to 90 percent of ASTM D1557 with light equipmenfi so as nofi to impose
excessive lateral loads on the walls.
S#ructural fill/backfill must be placed under the fu11-time observation of a representa#ive of the
geotechnical engineer, and the specified compacted density and mois#ure content of each liit
Bergquis#Enginee�ng Services Page 8 of 10
.1 .
; Proposed Subdivision (Jericho Plat) February 14,2004
Renton,Washington BES Project Number 200402,-Report 1
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'j must be verified by test, prior to placement of subsequent lifts. Placement on frozen ground
�� must not be attempted.
�� -�� 6.5 Drainage
, ; Good drainage is critical to the performance of earth-supporfed structures such as
► e
foundations and retaining walls. Therefore, construction grades and final site grades must be
f j designed to prevent water from ponding in areas on or adjacent to foundations, slabs-on-
grade, and pavements. Infiltration of water into foundation and utility excavations shall be
�j prevented during construction and throughout the life of the project.
ii
►t A perimeter foofing drain-system consisting of a perForated pipe surrounded by at least six
�s inches of washed gravel will be required. The washed gravel must be separated from the
�� surrounding soil by a fiiter fabric such as Mirafi� 140N. The collected water must be tight-
,
j; lined away from the building to a suitable discharge system but not discharged onto the top
r�
of the any slopes. Roof and surFace drains must be provided but they not must be connec#ed
;,
to the footing-drain system. Roof drains may be discharged into properly constructed,
infiltration trenches on each Lot. A schematic of a foofing-drain system is presented in the
�� Appendix of this report.
;:
' Where pavement does not immediately abut structures, slopes, with an outfall o#at least three
� (3) percent for a minimum distance of five (5) feet from exterior footings, must be provided.
�� 6.6 Groundwafier
Groundwater was encountered in the form of seepage above the more compact glacial till �I,
soils at this site. In general, except for the low area in the southwest comer of the site,
groundwater should not be an issue for this project.
' `-�J Erosion
The soils at this site classify as fine-grained SAND-SILT (SM) some gravel according to the
Unified Soil Classification System. These soifs have a relatively high erosion potential,
however, because of the shallow slopes on this site, properly placed silt fences and straw
bales should be sufficient for erosion control even during periods of heary rainfall.
Bergquist Engineering Seroices Page 9 of 10
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; j Proposed Subdivision {Jericho Plat) February 14, 2004
Renton, Washington BES Project Number 200402,-Report 1
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6.8 Construction Observation and Testing
I� The recommendations presented in this report rely on adequate observation and testing of
t construction materials and procedures by the geotechnical engineer or his qualified
�� representative. At a minimum, the testing program must include:
, i
�� • Observation and review of site clearing and review of a11 foundation excavafiions to
�� evaluate whether actual conditions are consistent with those encountered during
exploration.
[�
� • Observafiion and testing of placement and compaction of all fill and backfill
�� materials to evaluate compliance with specifications.
ii
.�
• Field inspection and laboratory tes#ing of materials and field inspectian of inethods
as required by the appropriate Uniform Building Code. Typically, this includes
1
inspecfiion of piacement of reinforcing steel; inspection and tesfiing of portiand
cement concrete to evaluate compliance with specifications regarding slump,
' temperature, air content, and strength.
7. REPORT LIMITATIONS
The recommendations presented in this report are for fihe exclusive use of GWC, Inc. for the
proposed residential development on King County Parcel Numbers: 1523059045,
1523059019, 1523059047, 1523059148, and 1523059033 in Renton, Washington. The
recommendations are based on the subsurface information obtained by Bergquist
Engineering Services (SES) and on design details provided by Mr. Jim Jaeger of Jaeger
Engineering. If there are any revisions to the plans or if deviations from the subsurface
conditions noted in this reporf are encountered during construction, BES must be notified
immediately to determine whether changes to the foundation recommendations are required.
After the plans and specifications are more complete, the geotechnical engineer must be
provided the opportunity to review them to check that these engineering recommendations
have been interpreted properly.
000
Bergquist Engineering Services Page 10 of 10
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viciNi�r �P
Project Name: Proposed Jericho Plat
Subdivision Bergquist Engineering For: GWC Inc.
ocation: enton, as ington Services
Date: Februa 2004 BES Project Number: 200402-1
A1
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SITE PLAN
Project Name: Proposed Jericho Plat
Subdivision Bergquist Engineering For: GWC Inc.
ocafion: enton, as ington Services BES Project Number: 200402-1
Date: Februa 2004
A2
.
- T
t � Lo of Test Pit 1
9 I
'�� � ProjecF Jericho Plat Subdivision Excavation Rig: Cose 58QK 8ackhoe I�
�j tocafion: Renton, Washing#on Excavated By: D & K Construction, Inc. �
8ES Project No.: 200402-1 Logged 8y: R.A. Bergquist, P.E. I'
r� Date Excavated: January 28, 2004 Approximate Ground Su�face Elevation: 438'
: �{
� 1 � � L ' . �� _ " �',
��
�. � � � � Q : � _ '� , � . �
�� � Q� "' � � � c.u , Descrip#ion (Unifiecf $oil Classificafic��System� � '
.� agi E-�' � c.-'', � V � _ � �,.:
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_ .
s� _ BSl ML -- -_J�ark6�Q�tnFL�s.�s�nsly�ILI,-t10�@�7L�Y�I_�J99fS.�Rj2sS�1�-----------
�� 1 BS2 SM __ Reddish-brown, medium dense to very dense,SAND-SILT, —�—
_2_ _____ occasional gravel,occasional cobble (Weathered Til�) 2
�� ---- -- ----- -------------------- ---------
' Light brown, medium dense to dense,SAND-$1LT,occasiona{
: � — -- —
1 —3— BS3 SM _____grayel occasional_cobble (fil�_ _____y3
��
4 4
e ; - - SM Light brown, hard, SAND-SILT, some gravel — —
� 5
END OF TEST PIT. DRY AT COMPLETION.
�_ —6_ _� 6
—7 7
� Log o# Test Pit 2
` Projech Jericho P1at Subdivision Excavation Rig: Case 580K Backhce
_ _ Locafion: Ren#on,Washington Excavated By: D&K Construction, Inc.
BES Project No.: 2(30402-1 Logged By_ R.A Bergquist, P.E_
' Date Excavated: January 28, 2004 Approximate Ground Surface Elevation: 435'
m �:-:
m °' '
,�r �� . cn o', 3 �'� ; . ,.'Y '
s Q Z � ,� E N � � _ . �,tlescripf►on (Uni�ie�SoFI Classiflca#ion System� .,
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: � � � � � � �
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.. ._ � _ ,.___- � -.... _-..�, .,._. . ��_ -,- ,.>.,. w., ,_�, ; _
- ---DQrk biQ�n.l��e.�andx S U,T.fr�cs_gr���l$�L�t��IQp�Q�1�---------_
—�— Reddish-brown, medium dense SAND-SILT,some gravel, occasional —�—
—2_ BSl SM 15.3 cobb4e (Weathered Till) 2
—3_ BS2 SM 13.1 3
_ Light gray to gray, medium dense to dense SAND-SILT, occasioRal
4_ gravel, occasional cobble (Till) 4
� 5
END OF TEST PfT. DRY AT COMPLETION.
6 `� 6
� 7
A3
� � . ,
Log of Test Pifi 3 �,
`� � Project: Je�cho Plat Subdivision Excavation Rig: Case 580K Backhoe ,
Q y Location: Renton, Washington 6ccavated By: D&K Constructio�, Inc.
BES Project No.: 200402-1 Logged 8y: R.A. Bergquist, P.E.
�r� Date Excavated: January 28,2004 Approximate Grou�d $urface Elevation: 429'
� 3 (: . � � . , _ _ ,
j
.� . �.��. � ' � +� '.^ . �, . .+ �. . ` �.
�� s " �� ' � � , � c °� Descr�pfiori (Unified S�il Classi�icc�tion S}rstetn� , r ,.
3 l a°'i � -v � in ° c° a
c � � x_ ,.
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. .� .,, ,._. _ ., . _.. . .,. .
��t _ ML -_12ark.I��2�n,�lo�zss�Ss�n�ly��LI��UC@8t"L1Y@L��Q9��Qj2s91�---------"-
i � _1_ BS1 SM -- Reddish-brown, loose,SAND-SILT, occasional gravel _1
. �1Nealhered Till) ,,-
— �------------------- -------------------------
�� _2_ BS2 SM i�-2 V9�t brown, loose,SAND-SILT, occasional gravel, occasional (fill) —2—
- � — ---Gr------------------------------------------------------3
' 3
F' _ — BS3 SM t�.0 Qy, dense SAND-SILT, occasinal gravel,trace eobble (Till)
4— -----------------------------------------------------------4
—� BS4 S P 13.2 5
r F _ _ _
_ Gray, dense SAND, some silt, occasional grave)
_ . 6_ 6
7 END OF TEST PIT. DRY AT COMPLETION. 7
Log of Test Pit 4
` Projech Jericho Plat Subdivisian Excavation Rig: Cose 580K Bockhoe
_ Locafion: Renton,Washington Excavated By: D&K Construcfion, Inc.
BES Project No.: 200402-1 Logged By: R.A. Bergquist, P.E.
' Date Excavated: January 28, 2Q04 Approximate Ground Surface Elevation: 427'
. 7 --- Q m` ' . , _ :" _ _ -tr
.. � �.-a , � _ � C .^ , ' . ,� '. �. ,
,_ v , � 3— �` ., O , �� ] �: C ; . � . "� _� � � .,. . '.
. , Q Q-Z L�-, �. o o m Descripfion �l�nified So�i Cldssificahan System� �
m � � � v, � vn�
� �, � -
_.. _ . _ _ _ . . . , ,,,- , _,
: : _ ___Ds�rk biQ�n.144S.6.��1RdX,�LI,T..t�.cg_g ca��l�����IQ p�Q�l)----------_
1_ �
—2 BS1 SM 29.9 Reddish-brown, softSILT � _
2
END OF TEST PIT.
3_ 3
—4_ 4
�_ 5
6_ 6
7 7
A4
�� Log of Test Pit 5
�� � Projech Jericho P1at Subdivision E�ccavafion Rig_ Case 580K Backhoe
j� Location: Renton, Washington Excavated By: D 8�K Construction, Fnc.
BES Project No.: 200402-1 Logged By: R. A Bergquist, P.E.
�� DQte Excavated: Jdnuary 28, 2004 Approximate Ground Surface Elevatio�: 431'
� 1 � � �
a� �.:
� ti E � a ` � t��,
� s °3 ' � � � ` v Desc�{p�or� (tJRi#ied Soi� CEassificotion Sysfetn� ;
c
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t� � �
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,._ , . , � ,.,_- . _.. : ,,._.. . . _ _ .. __.
�� 1v{L -_�2ark�cQ�n,�lQo��.�s►ns�y��LT,�#ro�e�oY��&��f��C�zss����---- ------
� � _1_ _1_
Reddish-brown, loose,SAND-SILT, occasional gravel, occasional
� 2 BS1 SM 28.2 cobble (Weathered Till) 2
— — -----------------------------------------------------�---
3 3
� _ —4— BS� SM �3.4 Gray, dense SAND-SILT, occasional gravel,trace cobble (Till} �
5 5
_ _ —6 6
_ END OF TEST PIT.
7 7
Log of Test Pit 6
� Projecl: Jericho Pln#Subdivision F�ccavafion Rig: Case 580K Bacichce
- - Location: Re�►ton,Washington Excavated By: D&K Construction, Inc.
$ES Project No.: 200402-i Logged By: R.A. Bergquist, P.E.
Date Excavated: January 28, 2d04 Approximate Ground Surface Elevation: 436'
_ _ m � �� ;_ -
m T� m " ,� -
• _ . .,.- '
, . � , e� � � � � *�- � � � ' � =
`� fl-Z �n >, a o @ ` ' Descripfion �Un�fiec�5a�I CfassEfiC�ore�ystem�
m � -II � ,n . � U � - ;
- , � ,a.c,. _
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_ ._ . .. r.._�:
: . — ''`----Qp��EcZy+r�F�o2sg��andx$I�T,�trgcggraygl &roots�Co�soi�------.
1_
----------��szvft�IQ9�s SAND-�llJ��s-sQsi�nal�r���l--------------=1=
BS1 SM 19.7
2- BS2 SM 23.� Reddish brown, loose SAND-SILT,trace gravel,trace cobble 2_
{Weatf�ered Till)
3- --------------------------------------------------------�-�-3
—4— BS3 SM }8_7 Gray mottled reddish gray, dense to very dense SAND-SfLT, 4_
occasional gravel, occasional cobble (Cifl)
5 5
END OF TEST PIT.
6 ' 6
7 7
A5
�� .
`� Log of Test Pit 7
'�� � ProjecF: Je�cho P1at Subdivision Excavation Rig: Case 580K Backhce
,j Location: Renton,Washington Excavated By: D& K Construction, Inc.
BES ProjecF No.: 200402-1 Logged By: R. A Bergquist, P.E.
'� Date Excavated: January 28,2D04 Approximate Ground Surface Elevation: 441'
,
i
„ .. ;--
a, m � s
� � � � o_ ? � � ` .
� � Q� � � � c 'U Deset-�ption (Unified Soil Cfassificatio� System) �,Y '`
� a�i � � � � � � °,...�- :L
� ° � a =`
� � s,
. �-. _ ., . �_ . . . _ ,
. ,.. .-,.
_ ML __J2adc.I�cQv�n���S.�Sat1i���Z�tr9G@$CUY@L�J9Q��C.QF2SA1�_--_ -_ -
.� —1— —1—
_2— BS1 SM 15.2 Reddish-brown, loose, SAND-SILT,some gravel {Weathered Till) 2
,� -------------------------------------------------------------
k — —
-3- BS2 SM 16.0 -3-
R —4 Gray-brown, dense SAND-S(LT,with gravel, trace cobble (Till) 4
.1 — — — —
5 $
END OF TEST PIT. DRYAT COMPlETfON.
' 6 5
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7 7
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� TEST PIT LOG NOTES
�� These notes and test pit logs are intended for use wifih fihis geotechnical report for the
purposes and project described therein. The test pit logs depict BES's interpretation of
subsurface conditions at the location of the tes# pit on the date nofied. SubsurFace conditions
� may vary, and groundwater levels may change because of seasonal variations or numerous
� other facfiors. Accordingly, fihe test pit logs should nofi be made a parf of construction plans
1 or be used to define construction conditions.
�
i
The approximate locations of the test pits are shown on the Site Plan. The test pits were
� located in the field by estimating distances from existing site features. Elevations were
� interprefied from topographic survey perFormed by DRYCO Surveying, Incorporated and
,
provided by Jaeger Engineering.
E uSample Type" refers to the sampling method and equipment used during exploration where:
,� "BS" indicates a bulk sample taken from the ground surface or from the backhoe bucket.
.
.i
` NMoisture Content" refers to the moisture content of the soil expressed in percenfi by weight as
° determined in the laboratory.
"Descripfiion and Classification" refer to the materials encountered in the test pit. The
j descriptions and classifications are generafly based on visual examination in the field and
laboratory. Where noted, laborafiory tests were perforrned to defiermine fihe soi) dassification.
; The terms and symbols used in the test pit logs are in general accordance with the Unified
Soil Classificafion System. Laboratory tes�s are performed in general accordance with
� applicabfe procedures described by the American Saciety for Testing and Materials.
"��. " Indicates location of groundwater at the time noticed.
4
�
� Indicates location of seepage of water and the time noticed.
TERMS for RELATIVE DENSfTY of NON-COHESIVE SOIL
Term Standard Penetration Resistance "N"
Very Loose 4 or less
Loose 5 to 10
- Medium Dense 11 to 30
Dense 31 to �0
Very Dense Over 50 blows/foot
A7
��
r� .
t
r� .
j � TEST PIT LOG NOTES continued
f�
�E TERMS for RELATIVE CONSISTENCY of COHESIVE SOIL
�� Term Unconfined Compressive Strength
Very Soft 0 to 0.25 tons/square-foot
�� Soft 0.25 to 0.50 tsf
� Medium Stiff 0.50 to 1 .00 tsf
StifF 1 .00 to 2.00 tsf
'� Very Stiff 2.00 to 4.00 tsf
j Hard Over 4.Q0 tsf
,�
�� DEFINITION of MATERIAL by DIAMETER of PARTICLE
,�
1 Boulder 8-inches+
Cobble 3 to 8 inches
* Gravel 3 inches to 5mm
, Coarse Sand 5mm to 0.6mm
Medium Sand O.bmm to 02mm
1 Fine Sand 0.2mm to 0.074mm
� Silt 0.074 to 0.005mrr�
Clay less than 0.005mm
, �
A8
r� .
, �
r� ,
�� UNIFIED SOIL CLASSIFlCATION SYSTEM (USCS)
COARSE GRAfNED SOILS
(Less than 50%fines. Fines are soils passing the#200 sieve.)
�� GROUP SYMBOL DESCR{PT10N MAlO[t DIVISIONS
GW Wefl-groded GRAVELS o�GRAVEL-SAND mixtures,
less Nwn 596 fir�c.
r� Poorly graded C3RAVELS or GR,4VELSAND mixtures,
� � GP I�tha�,s�fi�. GRAVELS
Silfy GRAVELS,GRAVEL-SAND-SILT modures,rrcore �Ofe than half of coarse fraciion is farger
�� GM than 129G fi�es. than No.4 s7eve.
,j GC Clayey GRAVELS,GRAVEL-SAND-CtAY mixtures,
more than 1296 fi�s.
'� S� Well-groded SANDS or Gravelly SANDS mixtures, �
1� less tlxin 5�fines.
SP i Poorfy graded SANDS or Gravelly SAN�S mixtures,
less than 5%finps- $AND$
�� More than half of coarse fraction is smailer
j SiliY SANDS, SAND-S11T moctures,more than 1296
' S� fines. � than No.4 sieve.
�� SC Clayey SANDS, SA{�iD-CLAY mixtures,more thon
1296 f�nes '
`j Note:Coarse-grained soils receive dual symbols if they contain between 5 and 12 percent fines.
.� �I
` FINE-GRAlNED SOILS '
p {More than SO%fines. Fines are materials passing the#200 sieve) �
GROUP SYMBOL DESCRIPTION MAfQR D1VfS10NS
` Ml Inocganic SILTS,very fine SANDS,ROCK FLOUR, ,
Sil1y or Clayey SANDS
1
4r�orga�ic CLAYS of bw to medium plasticity, {
i CL ' Gravelly ClAYS,Sandy CIAYS,Silty CLAYS,Cean � SILjS ttnd CLf�Y$
� CIAYs I Liquid limit less than 50
' T Orc3anic SILTS,or organic Sifty CLAY$of bw i
' Q�
plasticity
IInorgonic$ILTS,Mirnceous or Diotomaceous fine i
�H I SANDS or51LTS,Elastic SlLTS ;
� SILTS and CLAYS
�
�
e Cf-{ Inorganic CLAYS of high piasticiiy,fat CLAYS E Liquid limit greater than 50
1 �{-� Organic CLAY$of inedium to high plasFicity �
i R
�
pZ G PE47,MUCK,ar,d ot�,h;5hly o�anic 5oil� � Nighly organic soiis
1 Note: Fine-grained soils receive dual symbols if their limits plot IeN of the'A'Li�e and have a plasticity index(PI)of 4 to�
. percenf.
UNIFIED SOIL C1.ASSlFICATION SYSTEM
Bergquist Engineering �
I Services
A9
�
: i
Y
.,
i�
LI
�� I I
�� Interior Floor I
il � ,
� I
(� a II
i � c� I
� Poly sheeting ,
d
; vapor barrier
, �� �a e ��
; > ��erio� G � � Crawl Space
. , � � �� �
:: � � � �
�, � \ � � Backfill
" \ / \ o \
, // //
� , � � o \� \� \�
a
, o �oo � o \ \ \
�� / // // /
�� � —, \ \�\�\�\ �
„ , � �
Ej � Four-inch diameter, \
I' ., �1 Schedule 40, perforated Native undisturbed soil
;� ' 1 PVC pipe sloped to drain
�
, `
� � Mirafi 140N wrapped around
` � clean gravel
�
�Tightline roof drain Not to Scale
SCHEMATIC OF FOOTING DRAlN
Project Name: Proposed Jericho Plat
Subdivision Bergquist Engineering For: GWC Inc.
ocation: enton, as ington Services
BES Project Number: 200402-1
Date: Februa 2004
A10