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GEOTECHNICAL ENGINEERING STUDY
PROPOSED CONSUMER CONNECTION �s
OFFICE BUILDING
WHITMAN COURT NORTHEAST
RENTON, WASHINGTON
E-8342
July 17, 1998
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GEOTECHNICAL ENGINEERING STUDY
PROPOSED CONSUMER CONNECTION
OFFICE BUILDING
WHITMAN COURT NORTHEAST
RENTON, WASHINGTON
1 E-8342
July 17, 1998
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PREPARED FOR
CR PROPERTIES, LLC
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MitcheMIcGinnis
Staff Geologist
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Kyle R. Campbe �.���g1
Manager of Geotechnic
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Ex7pis S 'II[Ak3 7
Earth Consultants, Inc.
1805 - 136th Place Northeast, Suite 201
Bellevue, Washington 98005
(425) 643-3780 CITY OF REP,,TON
REC EiV E9
JAN 0 8 1998
6uifLbiNO DiVIISIOiV
IMPORTANT INFORMATION
ABOUT YOUR
GEOTECHNICAL ENGINEERING REPORT
More construction problems are caused by site subsur- technical engineers who then render an opinion about
face conditions than any other factor. As troublesome as overall subsurface conditions.-their likely reaction to
subsurface problems can be, their frequency and extent proposed construction activity,and appropriate founda-
have been lessened considerably in recent years,due in tion design. Even under optimal circumstances actual
large measure to programs and publications of ASFE/ conditions may differ from those inferred to exist.
The Association of Engineering Firms Practicing in because no geotechnical engineer, no matter how
the Geosciences. qualified.and no subsurface exploration program, no
matter how comprehensive.can reveal what is hidden by
The following suggestions and observations are offered earth, rock and time.The actual interface between mate-
to help you reduce the geotechnical-related delays,
cost-overruns and other costly headaches that can vials may be far more gradual or abrupt than a report
indicates.Actual conditions in areas not sampled may
occur during a construction project. differ from predictions. Nothing can be done to prevent the
unanticipated,but steps can be taken to help minimize their
A GEOTECHNICAL ENGINEERING impact. For this reason, most experienced owners retain their
geotechnical consultants through the construction stage, to iden-
REPORT IS BASED ON A UNIQUE SET tify variances,conduct additional tests which may be
OF PROJECT-SPECIFIC FACTORS needed,and to recommend solutions to problems
encountered on site.
A geotechnical engineering report is based on a subsur-
face exploration plan designed to incorporate a unique SUBSURFACE CONDITIONS
set of project-specific factors.These typically include:
the general nature of the structure involved, its size and CAN CHANGE
configuration:the location of the structure on the site Subsurface conditions may be modified by constantly-
and its orientation:physical concomitants such as changing natural forces. Because a geotechnical engi-
access roads, parking lots,and underground utilities, neering report is based on conditions which existed at
and the level of additional risk which the client assumed the time of subsurface exploration,construction decisions
by virtue of limitations imposed upon the exploratory should not be based on a geotechnical engineering report whose
program.To help avoid costly problems.consult the adequacy may have been affected by time. Speak with the geo-
geotechnical engineer to determine how any factors technical consultant to learn if additional tests are
which change subsequent to the date of the report may advisable before construction starts.
affect its recommendations.
Construction operations at or adjacent to the site and
Unless yoyr consulting geotechnical engineer indicates natural events such as floods,earthquakes or ground-
otherwisz. your geotechnical engineering report should not water fluctuations may also affect subsurface conditions
be used: and,thus. the continuing adequacy of a geotechnical
•When the nature of the proposed structure is report.The geotechnical engineer should be kept
changed, for example, if an office building will be apprised of any such events, and should be consulted to
w
erected instead ll parking garage. or if a refriger- determine if additional tests are necessary.
ated warehouse will be built instead of an unre-
-- frigerated one.
•when the size or configuration of the proposed GEOTECHNICAL SERVICES ARE
structure is altered: PERFORMED FOR SPECIFIC PURPOSES
•when the location or orientation of the proposed AND PERSONS
structure is modified:
•when there is a change of ownership. or Geotechnical engineers' reports are prepared to meet
• for application to an adjacent site. the specific needs of specific individuals. A report pre-
ilitu for problems p
t be ad -
Geotechnical engineers cannot accept responsibirate for
consulting
r a construct construction vil engineer may o
contractor, or even some other
which may develop if they are not consulted after factors consid- consulting civil engineer. Unless indicated otherwise,
ered in their report's development have changed. this report was prepared expressly for the client involved
and expressly for purposes indicated by the client. Use
se. or by the client
MOST GEOTECHNICAL "FINDINGS" by any other persons for any purpo
ARE PROFESSIONAL ESTIMATES for a different purpose, may result in problems. No indi-
vidual other than the client should apply this report for its
Site exploration identifies actual subsurface conditions iengineedr.pNo personose without
should first
apply this reportf�for�any purpose
only at those points where samples are cotechHical
taken, when 9
they are taken. Data derived through sampling and sub- othhrth anet at original
r al enlyineeremplated without first conferring
sequent laboratory testing are extrapolated by geo- 9 g
A GEOTECHNICAL ENGINEERING der the mistaken impression that simply disclaiming re-
REPORT IS SUBJECT TO sponsibility for the accuracy of subsurface information
MISINTERPRETATION always insulates them from attendant liability. Providing
the best available information to contractors helps pre-
Costly problems can occur when other design profes- vent costly construction problems and the adversarial
sionals develop their plans based on misinterpretations attitudes which aggravate them to disproportionate
of a geotechnical engineering report.To help avoid scale.
these problems, the geotechnical engineer should be
retained to work with other appropriate design profes- READ RESPONSIBILITY
sionals to explain relevant geotechnical findings and to CLAUSES CLOSELY
review the adequacy of their plans and specifications
relative to geotechnical issues. Because geotechnical engineering is based extensively
on judgment and opinion.it is far less exact than other
design disciplines.This situation has resulted in wholly
unwarranted claims being lodged against geotechnical
BORING LOGS SHOULD NOT BE consultants.1b help prevent this problem,geotechnical
engineers have developed model clauses for use in writ-
SEPARATED FROM THE
ten transmittals.These are not exculpatory clauses
ENGINEERING REPORT designed to foist geotechnical engineers' liabilities onto
Final boring g are logs developed b someone else. Rather, they are definitive clauses which
p y geotechnical engi- identify where geotechnical engineers responsibilities
neers based upon their interpretation of field logs begin and end.Their use helps all parties involved rec-
(assembled by site personnel)and laboratory evaluation ognize their individual responsibilities and take appro-
of field samples.Only final boring logs customarily are priate action. Some of these definitive clauses are likely
included in geotechnical engineering reports. These logs to appear in your geotechnical engineering report,and
should not under any circumstances be redrawn for inclusion in you are encouraged to read them closely. Your geo-
architectural or other design drawings,because drafters technical engineer will be pleased to give full and frank
may commit errors or omissions in the transfer process. answers to your questions.
Although photographic reproduction eliminates this
problem, it does nothing to minimize the possibility of OTHER STEPS YOU CAN TAKE TO
contractors misinterpreting the logs during bid prepara-
tion.When this occurs,delays,disputes and unantici- REDUCE RISK
gated costs are the all-too-frequent result.
Your consulting geotechnical engineer will be pleased to
To minimize the likelihood of boring log misinterpreta- discuss other techniques which can be employed to mit-
tion,give contractors ready access to the complete geotechnical igate risk. In addition,ASFE has developed a variety of
engineering report prepared or authorized for their use. materials which may be beneficial. Contact ASFE for a
Those who do not provide such access may proceed un- complimentary copy of its publications directory.
Published by
THE ASSOCIATION
A F OF ENGINEERING FIRMS
PRACTICING IN THE GEOSCIENCES
8811 Colesville Road/Suite G 106/Silver Spring, Maryland 20910/(301) 565-2733
O788/3M
Earth Consultants Inc.
t Geotechnical Engineers.Geologists F Environmental Scientists
July 17, 1998 E-8342
I CR Properties, LLC
400 - 108th Avenue Northeast
Bellevue, Washington 98004
Attention: Mr. Gary Chatwin
Dear Mr. Chatwin:
r
We are pleased to submit our report titled "Geotechnical Engineering Study, Proposed
Consumer Connection Office Building, Whitman Court Northeast, Renton, Washington." This
report presents the results of our field exploration, selective laboratory tests, and engineering
analyses. The purpose and scope of our study was outlined in our June 12, 1998 proposal.
Based on the subsurface conditions encountered at the site, it is our opinion the proposed
building may be supported using conventional spread footing foundation systems bearing on
competent native soils, competent existing fill, or new structural fill. Slab-on-grade floors may
be similarly supported.
We appreciate this opportunity'to be service to you. If you have any questions, or if we can
be of further assistance, please call.
Respectfully submitted,
EARTH CONSULTANTS, INC.
jx-
Kyle R. Campbell, P.E.
Manager of Geotechnical Services
MGM/SDD/KRC/kml
1
1805- 136th Race N.E.,Suite 201.Bellevue,Washington 98005
E211evue(425)6 3 3180 Seat'le(2 6)464-1584 FAX(425)74-608-60 Tacoma 1,253)272 6608
TABLE OF CONTENTS
E-8342
PAGE
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Proiect Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SITE CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2
Surface 2
Subsurface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Groundwater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3
Laboratory Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4
DISCUSSION AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
General . . . . . . . . . . . . . . . . . . . . . . 4
Site Preparation and General Earthwork . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Foundations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Slab-on-Grade Floors . . . . . . . . . . . . . . . . . . • ' . . . , . . . , . • . . • . . • . . . . . 6
Seismic Design Considerations 7
Excavations and Slopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Site Drain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
age
Pavement Areas 9
Utility Support and Backfill . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
9
LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
, , 10
Additional Services . . . . . . . . . . . . . . . . . . . . . " " " " " "
APPENDICES
Appendix A Field Exploration
Appendix B Laboratory Test Results
ILLUSTRATIONS
Plate 1 Vicinity Map
Plate 2 Test Pit Location Plan
Plate 3 Utility Trench Backfill
Plate Al Legend
Plates A2 through A5 Test Pit Logs
Plate 131 Grain Size Analyses
Plate B2 Atterberg Limit Test Data
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
PROPOSED CONSUMER CONNECTION
OFFICE BUILDING
WHITMAN COURT NORTHEAST
' RENTON, WASHINGTON
E-8342
INTRODUCTION
General
This report presents the results of our geotechnical engineering study for the proposed
Consumer Connection Office Building in Renton, Washington. The general location of the site
is shown on the Vicinity Map, Plate 1 . The purpose of this study was to explore the
subsurface conditions at the site and based on the conditions encountered to provide specific
geotechnical recommendations for the proposed development.
At the time our study was performed, the site, proposed building and our exploratory locations
were approximately as shown on the Test Pit Location Plan, Plate 2.
Project Description
We understand it is currently planned to develop the approximately 12,000 square foot
commercial lot with a one-story office supported on piers above a ground level parking area.
The proposed building will have a footprint of about forty-five (45) by one hundred twenty-five
(125) feet and will be constructed in the approximate center of the site.
The proposed building will be of wood-frame construction with the supports consisting of
cast-in-place concrete piers. On the lower lovel will be an elevator room with stairwell with
a slab-on-grade floor.
We anticipate column loads of eighty (80) to one hundred (100) kips and slab-on-grade floor
loads of about one hundred fifty (150) pounds per square foot.
The building will be surrounded by asphalt paved parking and driveway areas. Vehicle traffic
will consist of passenger vehicles and occasional service trucks.
If any of the above design criteria are incorrect or change, we should be consulted to review
the recommendations contained in this report. In any case, ECI should be retained to perform
a general review of the final design.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY E-8342
CR Properties, LLC Page 2
July 17, 1998
SITE CONDITIONS
Surface
The subject site is located on the east side of Whitman Court Northeast approximately one
hundred forty-five (145) feet south of the intersection of Northeast Sunset Boulevard and
Whitman Court Northeast in Renton (see Plate 1, Vicinity Map). The subject property is
bordered to the west by Whitman Court Northeast, to the east by an undeveloped, densely
vegetated lot, to the south by an asphalt parking lot north of an existing apartment complex
and to the north by a parking lot south of an existing office building.
The asphalt parking area located immediately north of the proposed building area is located
within an approximately forty (40) foot wide drainage easement. This drainage easement
contains an approximately thirty-six (36) inch diameter corrugated metal pipe that outlets to
a creek immediately northeast of the proposed building area.
The site is essentially flat, with little discernible elevation change across the site.
The site is vegetated with dense grass and localized brush,
Su
bsurface
Subsurface conditions were evaluated by excavating four test pits at the approximate
locations.shown on Plate 2. Please refer to the Test Pit Logs, Plates A2 through A5, for a
more detailed description of the subsurface conditions encountered at each test pit location.
A description of field exploration methods is included in Appendix A. The following is a
generalized description of the conditions encountered.
Drum At our test pit locations, we encountered a surficial layer of topsoil and duff that was
approximately five to six inches thick. The topsoil and duff was characterized by its dark
brown color and the presence of organic material and abundant roots. This soil is not suitable
00
for use in support of foundations, slab-on-grade floors or pavements. In addition, it is not
should it be mixed with material to be used as structural
suitable for use as structural fill, nor
pit fill.
Underlying the topsoil, we typically encountered four feet of loose fill comprised of silty sand,
and poorly graded sand with silt and gravel (Unified Soil Classification SM, and SP-SM,
respectively). A one and one-half foot thick layer of fill was encountered in Test Pit TP-2.
The fill was characterized by trace amounts of organic material, concrete rubble,
miscellaneous debris, and the loose consistency.
Earth Consultants, Inc,
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 3
Underlying the fill, we encountered silty sand (SM), poorly graded sand with silt (SP-SM),
poorly graded gravel with silt and sand (GP-GM), silt (ML) and silty sand (SM). The soils
contained variable amounts of gravel and cobbles. The upper two to three feet of the
observed native soils were typically loose to medium dense with trace amounts of organic
debris. At two to three feet below grade, the soils typically became medium dense to
approximately nine feet below grade. Below nine feet, the observed soils were typically
medium dense to dense to the maximum exploration depth of thirteen (13) feet below existing
grade.
Groundwater
Light to heavy seepage was encountered at the test pit locations. At each of the test pit
locations, perched groundwater seepage was observed at approximately eight to ten (10) feet
below grade. The seepage was observed entering the excavation along the top of an
approximately one foot thick silt layer observed in each of the test pits. The soils below the
silt layer were typically wet to saturated.
Based on anticipated excavation depths and due to depth of the observed groundwater
seepage, we do not anticipate significant seepage will be encountered in building or utility
excavations. However, the contractor should be prepared to address the potential for
groundwater seepage into excavations, especially deep utility excavations.
The contractor should also be aware that groundwater levels are not static. There will be
fluctuations in the groundwater level depending on the season, amount of rainfall, surface
water runoff, and other factors. Seepage levels and flow rates are typically higher in the
wetter winter months (typically October through May).
Laboratory Testing
Laboratory tests were conducted on several representative soil samples to verify or modify
the field soil classification and to evaluate the general physical properties and engineering
characteristics of the soils encountered. Visual field classifications were supplemented by
Atterberg Limit test data and grain size analyses on representative soil samples. Moisture
content tests were performed on all samples. The results of the laboratory tests performed
on specific samples are provided either at the appropriate sample depth on the individual test
pit logs or on a separate data sheet contained in Appendix B. It is important to note that
these test results may not accurately represent the overall in-situ soil conditions. Our
geotechnical recommendations are based on our interpretation of these test results and their
use in guiding our engineering judgement. ECI cannot be responsible for the interpretation of
these data by others.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC Page 4
July 17, 1998 Page
In accordance with our Standard Fee Schedule and General Conditions, the soil samples for
this project will be discarded after a period of fifteen days following completion of this report
unless we are otherwise directed in writing.
' DISCUSSION AND RECOMMENDATIONS
General
' Based on the results of our study, it is our opinion the site can be developed generally as
planned. Building support can be provided using conventional spread footing foundation
system bearing on competent native soil, competent existing fill, or new structural fill. The
existing fill was observed to be in a loose condition. If loose soils are encountered at the
footing or slab subgrade elevation, the subgrade soils should be compacted in-place to the
requirements of structural fill. It may be necessary to overexcavate excessively loose soils
and replace them with structural fill. Slab-on-grade floors can be similarly supported.
This study has been prepared for specific application to this project only and in a manner
consistent with that level of care and skill ordinarily exercised by other members of the
profession currently practicing under similar conditions in this area for the exclusive use of CR
Properties, LLC and their representatives. No warranty, expressed or implied, is made. This
report, in its entirety, should be included in the project contract documents for the information
of the contractor.
Site Preparation and General Earthwork
The proposed building area should be stripped and cleared of all surface vegetation, organic
matter, and any other deleterious material. Based on the thickness of the topsoil and root
layers encountered at our test pit locations, we estimate a stripping depth of five to six
inches. Stripped materials should not be mixed with materials to be used as structural fill.
Following the stripping operation, the ground surface where structural fill, slabs or foundations
are to be placed should be observed by a representative of ECL Proofrolling may also be
necessary to identify loose or soft areas.
The existing fill underlying the site is in a loose condition. If loose soils are encountered at
the footing or slab subgrade elevation, the loose soils should be compacted in-place to the
requirements of structural fill. Alternatively, the loose soils may be overexcavated and
replaced with structural fill. If adequate, in-place compaction cannot be accomplished the soil
should be removed and replaced with structural fill.
Earth Consultants, Inc.
GEOTEC HNICAL ENGINEERING STUDY
CR Properties, LLC Page 5
July 17, 1998 Page 5
Structural fill is defined as compacted fill placed under foundations, roadways, slabs,
pavements or other load-bearing areas. Structural fill under foundations should be placed in
horizontal lifts not exceeding twelve (12) inches in loose thickness and compacted to a
minimum of 90 percent of its laboratory maximum dry density determined in accordance with
ASTM Test Designation D-1557-91 (Modified Proctor). The fill materials should be placed at
or near their optimum moisture content. Fill under pavements and walks should also be
placed in horizontal lifts and compacted to 90 percent of maximum density except for the top
twelve 0 2) inches which should be compacted to 95 percent of maximum density.
During dry weather, most soils which are compactible and non-organic can be used as
' structural fill. Based on they results of our laboratory tests, the on-site soils at the time of our
exploration appeared to be near the optimum moisture content and should be suitable for use
in their present condition as structural fill, provided the grading operations are conducted
during dry weather. However, laboratory testing indicates that some of the site soils have
more than five percent fines passing the No. 200 sieve. These soils will degrade if exposed
to excessive moisture, and compaction and grading will be difficult if the soil moistures
increase significantly above their optimum conditions.
If the site soils are exposed to moisture and cannot be adequately compacted then it may be
necessary to import a soil which can be compacted. During dry weather, non-organic
compactible soil with a maximum grain size of six inches can be used. Fill for use during wet
weather should consist of a fairly well graded granular material having a maximum size of six
inches and no more than 5 percent fines passing the No. 200 sieve based on the minus
3/4-inch fraction. A contingency in the earthwork budget should be included for this
possibility.
Foundations
Based on the encountered subsurface soil conditions, preliminary design criteria and assuming
compliance with the preceding Site Preparation and Grading section, the proposed office
building may be supported on a conventional spread footing foundation system bearing on
competent native soil, competent existing fill, or new structural fill. The existing fill is in a
loose condition. If loose soil is encountered at the footing subgrade elevation, in-place
compaction will be necessary. Alternatively, the loose soils may be overexcavated and
replaced with structural fill.
For frost protection considerations, exterior foundation elements should be placed at a
minimum depth of eighteen (18) inches below final exterior grade. Interior spread foundations
can be placed at a minimum depth of twelve (12) inches below the top of slab, except in
unheated areas, where interior foundation elements should be founded at a minimum depth
of eighteen (18) inches. Continuous and individual spread footings should have minimum
widths of eighteen (18) and twenty-four (24) inches, respectively.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC Page 6
' July 17, 19-98 Page 6
The foundations may be designed for an allowable soil bearing capacity of two thousand five
hundred (2,500) psf for competent native soil, competent existing fill, or structural fill.
ILoading of this magnitude would be provided with a theoretical factor-of-safety in excess of
three against actual shear failure. For short-term dynamic loading conditions, a one-third
increase in the above allowable bearing capacities can be used.
For the above design criteria, total settlement of foundations is expected to be less than one
inch. Differential settlements are expected to be less than one-half inch. The majority of the
anticipated settlement should occur during construction as the dead loads are applied.
Horizontal loads can be resisted by friction between the base of the foundation and the
supporting soil and by passive soil pressure acting on the face of the buried portion of the
foundation. For the latter, the foundation must be poured neat against the competent
native soils, or backfilled with structural fill. For frictional capacity,a coefficient of .35 can
be used. For passive earth pressure, the available resistance can be computed using an
equivalent fluid pressure of three hundred fifty (350) pcf. These lateral resistance values are
allowable values, a factor-of-safety of 1 .5 has been included. As movement of the foundation
element is required to mobilize full passive resistance, the passive resistance should be
neglected if such movement is not acceptable.
Footing excavations should be observed by a representative of ECI, prior to placing forms or
rebar, to verify that conditions are as anticipated in this report.
Slab-on-Grade Floors
iWe anticipate slab-on-grade floors will be used in the stairway/elevator room at the ground
level.
Slab-on-grade floors may be supported on competent existing fill, competent native soil or on
new structural fill. Where loose soil is encountered at the slab subgrade elevation, the loose
soil should be compacted to the previously discussed requirements for structural fill.
Disturbed subgrade soils should either be recompacted or replaced with structural fill.
Concrete slabs should be provided with a minimum of four inches of free-draining sand or
gravel. In areas where slab moisture is undesirable, a vapor barrier such as 6-mil plastic
membrane should be placed beneath the slab. The vapor barrier should be sealed at the
seams and care taken during construction not to damage it. Two inches of damp sand may
be placed over the membrane for protection during construction and to aid in curing of the
concrete.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 7
Seismic Design Considerations
The Puget Lowland is classified as a Seismic Zone 3 in the 1997 Uniform Building Code
(UBC). Earthquakes occur in the Puget Lowland with regularity, however, the majority of
these events are of such low magnitude they are not detected without instruments. Large
earthquakes do occur, as indicated by the 1949, 7.2 magnitude earthquake in the Olympia
area and the 1965, 6.5 magnitude earthquake in the Midway area.
There are three potential geologic hazards associated with a strong motion seismic event at
this site: ground rupture, liquefaction, and ground motion response.
Ground Rupture: The strongest earthquakes in the Puget Lowland are widespread, subcrustal
events, ranging in depth from thirty (30) to fifty-five (55) miles. Surface faulting from these
deep events has not been documented to date. Therefore, it is our opinion, that the risk of
ground rupture at this site during a strong motion seismic event is negligible.
Liquefaction: Liquefaction is a phenomenon in which soils lose all shear strength for short
periods of time during an earthquake. Groundshaking of sufficient duration results in the loss
of grain to grain contact and a rapid increase in pore water pressure, causing the soil to
behave as a fluid. To have a potential for liquefaction, a soil must be cohesionless with a
grain size distribution of a specified range (generally sand and silt); it must be loose; it must
be below the groundwater table; and it must be subject to sufficient magnitude and duration
of groundshaking. The effects of liquefaction may be large total and/or differential settlement
for structures founded in the liquefying soils.
In our opinion, the potential for liquefaction induced settlement at the site is minimal.
Ground Motion Response: Based on the encountered soil conditions, it is our opinion soil
profile type Sp, Stiff Soil as defined in Table 16-J of the 1997 Uniform Building Code (UBC)
should be used to characterize the site soils.
Excavations and Slopes
In no case should excavation slopes be greater than the limits specified in local, state and
Federal safety regulations. Based on the information obtained from our field exploration and
laboratory testing, the site soils expected to be encountered in excavations would be classified
as Type C by OSHA, and as such, temporary cuts greater than four feet in height should be
sloped at an inclination no steeper than 1 .5H:1 V. If slopes of this inclination, or flatter,
cannot be constructed, temporary shoring may be necessary. This shoring will help protect
against slope or excavation collapse, and will provide protection to workers in the excavation.
If temporary shoring is required, we will be available to provide shoring design criteria, if
requested.
Earth Consultants, Inc.
GEOTECHN ICAL ENGINEERING STUDY
CR Properties, LLC Page 8
July 17, 1998 Page 8
Permanent cut and fill slopes should be inclined no greater than 2H:1 V.
The above information has been provided solely as a service to our client. Under no
circumstances should the above information be interpreted to mean that ECI is assuming
responsibility for construction site safety or the contractor's activities; such responsibility is
not being implied and should not be inferred.
Site Drainage
Light to heavy groundwater seepage was encountered in our test pits at depths ranging from
eight to ten feet below grade. Due to the depth of the observed seepage, it does not appear
groundwater will present construction related issues, unless excavations extend to depths of
eight to ten feet.
However, if groundwater seepage is encountered during construction, the bottom of the
excavation should be sloped to one or more shallow sump pits. The collected water can then
be pumped from these pits to a positive and permanent discharge, such as a nearby storm
drain. Depending on the magnitude of such seepage, it may also be necessary to interconnect
the sump pits by a system of connector trenches. The appropriate locations of subsurface
drains, if needed, should be established during grading operations by ECI's representative at
which time the seepage areas, if present, may be more clearly defined.
The site should be graded such that surface water is directed off the site. Water must not
be allowed to stand in areas where foundations or slabs are to be constructed. During
construction, loose surfaces should be sealed at night by compacting the surface to reduce
the potential for moisture infiltration into the soils.
Pavement Areas
The adequacy of site pavements is related in part to the condition of the underlying subgrade.
To provide a properly prepared subgrade for pavements, the subgrade should be treated and
prepared as described in the Site Preparation and General Earthwork section of this report.
This means at least the top twelve (12) inches of the subgrade should be compacted to 95
percent of the maximum dry density (per ASTM D-1 557-91 ). It is possible that some localized
areas of soft, wet or unstable subgrade may still exist after this process. Therefore, a greater
thickness of structural fill or crushed rock may be needed to stabilize these localized areas.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 9
The following pavement sections for driveway and parking areas can be used:
• Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB)
material, or
• Two inches of AC over three inches of asphalt treated base (ATB) material.
• Four inches of Portland Cement Concrete (PCC).
All pavement materials should conform to WSDOT specifications. In our opinion, a Class B
asphalt mix should be used.
If the PCC pavement section is used, the subgrade should be moistened prior to concrete
placement. The PCC pavement section can be constructed in general accordance with the
practices for construction of slab-on-grade floors. A thickened edge is recommended on the
outside of the concrete pavement section. The concrete should achieve an average
compressive strength of 4,000 psi at 28 days.
Utility Support and Backfill
Based on the soil conditions encountered, the soils expected to be exposed by utility
excavations should provide adequate support for utilities.
Utility trench backfill is a primary concern in reducing the potential for settlement along utility
alignments;`particularly in pavement areas. It is important that each section of utility line be
adequately supported in the bedding material. The material should be hand tamped to ensure
support is provided around the pipe haunches. Fill should be carefully placed and hand
tamped to about twelve inches above the crown of the pipe before heavy compaction
equipment is brought into use. The remainder of the trench backfill should be placed in lifts
having a loose thickness of less than twelve inches. A typical trench backfill section and
compaction requirements for load supporting and non-load supporting areas is presented on
Plate 3.
LIMITATIONS
Our recommendations and conclusions are based on the site materials observed, selective
laboratory testing and engineering analyses, the design information provided to us by the
client, and our experience and engineering judgement. The conclusions and recommendations
are professional opinions derived in a manner consistent with that level of care and skill
ordinarily exercised by other members of the profession currently practicing under similar
conditions in this area. No warranty is expressed or implied.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 10
The recommendations submitted in this report are based upon the data obtained from the test
pits. Soil and groundwater conditions between test pits may vary from those encountered.
The nature and extent of variations between our exploratory locations may not become
evident until construction. If variations do appear, ECI should be requested to reevaluate the
recommendations of this report and to modify or verify them in writing prior to proceeding
with the construction.
Additional Services
As the geotechnical engineer of,record, ECI should be retained to perform a general review
of the final design and specifications to verify the earthwork and foundation recommendations
have been properly interpreted and implemented in the design and in the construction
specifications.
ECI should also be retained to provide geotechnical services during construction. This is to
observe compliance with the design concepts,specifications or recommendations and to allow
design changes in the event subsurface conditions differ from those anticipated prior to the
start of construction. We do not accept responsibility for the performance of the foundation
or earthwork unless we are retained to review the construction drawings and specifications,
and to provide construction observation and testing services.
Earth Consultants, Inc.
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Earth Consultants, Inc:
Geolechnical Engineers,Geologists 6 Environmenlal Scientists
Reference:
Vicinity Map
King County/Map 626 Consumer Connection Office Building
By Thomas Brothers Maps Renton, Washington
Dated 1998
Drwn. GLS Date June '98 Proj. No. 8342
Checked MGM Date 7/1/98 Plate 1
I
I
t---------I
I I
1 I
� Existing I
' I
I Wood Frame
� Office Bldg.
I Approximate Scale
' I — I
I I 0 20 40 80ft.
•SY i d � �1 � �i.
LEGEND
I
TP-1 -!- Approximate Location of
ECI Test Pit, Proj. No.
W My; E-8342, June 1998
Proposed Building
� I iC, k i I Existing Building
9 9
4 .0
Q �J Subject Site
� I I TP-1 � I
i
2 iTP-I Proposed Existing Asphalt Parking
Building i % Lot
i With Parking
Below
Earth Consultants, Inc.
'.TP-3 Gcotechnical Engineers,Geologists scien115ls
—•
I TP-2s Test Pit Location Plan
Consumer Connection Office Building
Renton, Washington
Drwn. GLS Date June '98 Proj. No.8342
Checked MGM Date 72/98 Plate 2
1 -
Non-Load Supporting Floor Slab or
Areas Roadway Areas
Varies
0
- o
- - o
a 0
95
-
0 0 o
85^
95
1 Foot Minimum
Backfill
90
Vanes
80
PIPE o' o o::
O.OQ 000• .o p .uQQ•'o•
..004 b
oaQo:o °o ".o.a..oq:
Bedding °'� o •'Q ;,os od.;ro,;, Varies
�6.••.co'oo. oa. . opoo°.•o•.°.•
LEGEND:
•:���2`h ,
�;�:� Asphalt or Concrete Pavement or Concrete Floor Slab
. • Base Material or Base Rock
Backfill; Compacted On-Site Soil or Imported Select Fill
Material as Described in the Site Preparation of the General
Earthwork Section of the Attached Report Text.
Minimum Percentage of Maximum Laboratory Dry Density as
95 Determined by ASTM Test Method D 1557-78 (Modified Proctor),
Unless Otherwise Specified in the Attached Report Text.
Bedding Material; Material Type Depends on Type of Pipe and
Laying Conditions. Bedding Should Conform to the Manufacturers
Recommendations for the Type of Pipe Selected.
.� TYPICAL UTILITY TRENCH FILL
Earth Consultants Inc Consumer Connection Office Building
fi "Ijj,gJ, , G„ Renton, Washington
Proi. No. 8342 Drwn. GLS Date July '98 1 Checked MGM Date 7/17/98 Plate 3
APPENDIX A
FIELD EXPLORATION
E-8342
Our subsurface exploration was performed on June 23, 1998. The subsurface conditions at
the site were explored by excavating four test pits to a maximum depth of thirteen (13) feet
below existing grade. The test pits were excavated by Evans Brothers subcontracted to ECI,
using a rubber-tire backhoe.
Approximate test pit locations were determined by pacing from features as shown on the site
map provided by the client. Test pit elevations were determined relative to each other. The
locations and elevations of the test pits should be considered accurate only to the degree
implied by the method used. These approximate locations are shown on the Test Pit Location
Plan, Plate 2.
The field exploration was continuously monitored by a geologist from our firm who classified
the soils encountered, maintained a log of each test pit, obtained representative samples, and
observed pertinent site features. All samples were visually classified in accordance with the
Unified Soil Classification System which is presented on Plate Al , Legend. Logs of the test
pits are presented on Plates A2 through A5. The final logs represent our interpretation of the
field logs and the results of the laboratory examination and tests of field samples. The
stratification lines on the logs represent the approximate boundaries between soil types. In
actuality, the transitions may be more gradual. Representative soil samples were placed in
closed containers and returned to our laboratory for further examination and testing.
Faith Consultants, Inc.
GRAPH LETTER TYPICAL DESCRIPTION
MAJOR DIVISIONS SYMBOL SYMBOL
Well-Graded Gravels,Gravel-Sand
Gravel Q •a 'Q ° GW gw Mixtures,Little Or No Fines
And Clean Gravels
Gravelly (little or no fines) M r GP Poorly-Graded Gravels,Gravel-
Coarse Soils ' ' ' gp Sand Mixtures,Little Or No Fines
Grained
Soils More Than GM Silty Gravels,Gravel Sand-
50% Coarse Gravels With gm Silt Mixtures
Fraction Fines(appreciable Retained On amount of fines) GC Clayey Gravels,Gravel Sand
No.4 Sieve gC Clay Mixtures
• Well-Graded Sands, Gravelly
Sand c °e v SW SW Sands, Little Or No Fines
And Clean Sand
(little or no fines) :�::: ;'�..:::
Sandy Poorly-Graded Sands, Gravelly
More Than Soils
50% Material Sp Sands, Little Or No Fines
M
Larger Than More Than SM
No.200 Sieve No. Sands, Sand-Silt Mixtures
50% Coarse Sands With Sm
Size Fraction Fines(appreciable
Passing No.4 amount of fines) SC SC Clayey Sands, Sand-Clay Mixtures
Sieve
ML Inorganic Silts 3 Very Fine Sands,Rock Flour,Silty-
MI Clayey Fine Sands;Clayey Silts w/Slight Plasticity
Fine Silts Liquid Limit CL Inorganic Clays Of Low To Medium Plasticity,
Grained And Less Than 50 � Cl Gravelly Clays, Sandy Clays, Silty Clays, Lean
Soils Clays
I I ( I I ( OL Organic Silts And Organic
Ililll OI
Silty Clays Of Low Plasticity
MH Inorganic Silts,Micaceous Or Diatomaceous Fire
More Than mh Sand Or Silty Soils
50% Material Silts Liquid Limit CH Inorganic Clays Of High
Smaller T4,an And Greater Than 50
No.200 Sieve Clays Ch Plasticity, Fat Clays.
SizeOH Organic Clays Of Medium To High
771
// Oh Plasticity, Organic Silts
pT Peat, Humus, Swamp Soils
Highly Organic Soils i• `�r 0r `�r Pt With High Organic Contents
. V y Topsoil Humus And Duff Layer
y y �
Fill Highly Variable Constituents
The discussion in the text of this report is necessary for a proper understanding of the nature
of the material presented in the attached logs.
DUAL SYMBOLS are used to indicate borderline soil classification.
C TORVANE READING,tsf l 2" O.D. SPLIT SPOON SAMPLER
qu PENETROMETER READING,tsf
W MOISTURE, %dry weight 24' I.D. RING OR SHELBY TUBE SAMPLER
P SAMPLER PUSHED
SAMPLE NOT RECOVERED WATER OBSERVATION WELL
pcf DRY DENSITY, lbs. per cubic ft.
LL LIQUID LIMIT, % SZ DEPTH OF ENCOUNTERED GROUNDWATER
PI PLASTIC INDEX DURING EXCAVATION
T SUBSEQUENT GROUNDWATER LEVEL W/DATE
►itants Inc. LEGEND
-thcons
1_��►
Pro .. No. 8342 Date July'98 Plate Al
Test Pit Log
Sheet of
Project Name:
Consumer Connection Office Building 1
Job No. Logged by: pate: Test Pit No.:
8342 MGM 6I23/98 TP-1
Ground Surface Elevation:
Excavation Contactor.
t390'
Evans Brothers
Notes:
v 'A � r+ Surface Conditions: Depth of Topsoil &Duff 5"
vv 0 ,�, En
LL R +� 124 U
°Y.) � a) r=, b �
1,4 rn n rn rn
P-S FILL: Brown poorly graded SAND with silt and gravel, loose, moist
1
-abundant roots to 4'
2 -trace concrete rubble
3
10.5 4 -12°� fine
P-G Brown poorly graded GRAVEL with silt and sand, loose, moist
•
5 -abundant cobbles
6 P-S Gray poorly graded SAND with silt, medium dense,wet
oa 7
20.4 8 -moderate seepage at 8'
ML Mottled brown SILT, medium dense, moist
40.9 s
P-S Gray poorly graded SAND with silt and gravel, medium dense,saturated
10 -caving
10.2 0
11
°
0 12
00
13 Test pit terminated at 13.0 feet below existing grade. Groundwater
seepage encountered at 8.0 feet during excavation.
NOTE: Elevation estimated from 1983 U.S.G.S. Bellevue South
Topographic Map.
a
I
0.
0 �T � Test Pit Log
i Consultants Inc' Consumer Connection Office Building
�
Y�
M FJ191TWc*e,Cc 1091SS Eiiviro.micrual Sc:ien�tsts Renton, Washington
a
Proj.No. 8342 Dwn. GLS Date July'98 Checked MGM Date 7l1198 Plate
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment_ They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log_
Test Pit Log
Sheet of
Project Name: ) )
Consumer Connection Office Building
--T-
Job No. Logged by: Date: Test Pit No.:
8342 MGM 6123/98 TP-2
Excavation Contactor: Ground Surface Elevation:
Evans Brothers ±390'
Notes:
e —4 v � Surface conditions: Depth of Topsoil &Duff 5":tall grass
to W _Q O Aa U t
�4 vn Q Cn v7
SM FILL: Dark brown silty SAND, loose, moist
1 -abundant roots,trace concrete debris
2 SM Reddish brown silty SAND, medium dense, moist
17.6 -trace charred wood fragments
3 small roots,trace ravel
,
417�—t- Brown poorly graded SAND wit
o
h silt, medium dense, moist
-contains gravel
0 5
6 -grades to gray
°
7
21.6 0 -heavy seepage at 8' along contact with silt
LL=45 PL=31 40.0 ° s ML Mottled brown SILT, medium dense, moist
PI=14
10 P-S Gray poorly graded SAND with silt and gravel, medium dense,wet
14.4
11
o -becomes dense
12
Test pit terminated at 12.5 feet below existing grade.Groundwater
seepage encountered at 8.0 feet during excavation.
o:,
i
1,
h
Test Pit Log
j I I;1 Earth ConSUlta 1tS Inc. Consumer Connection Office Building
m ;•:, ! < >�,, C, Renton, Washington
cc
° Proj. No. 8342 Dwn. GLS Date July'98 Checked MGM Date 7/7/98 Plate
H
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis an
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
Is information presented on this log.
Test Pit Log
Sheet of
Project Name:
Consumer Connection Office Building 1 1
Job No. Logged by: Date: Test Pit No.:
8342 MGM 6/23/98 TP-3
Excavation Contactor. Ground Surface Elevation:
IEvans Brothers ±390'
Notes:
a, r4 Surface conditions: Depth of Topsoil &Duff 5":tall grass
W +� ' 0. U
04 M rd N k+ fd U
� � Q rn cn
P-S FILL: Brown poorly graded SAND with silt, loose, moist
1 -abundant roots to 4'
' 9.0 2 -trace concrete debris
-metal wire in sidewall
3 -becomes reddish brown
76.1 4 ML Dark brown SILT with sand,loose,wet,contains organics, possible old
0
5 P-S Brown poorly graded SAND with silt, medium dense, moist
o`
6
o
0 7
-li ht seepage at 8' along contact
$
ML Mottled brown SILT, medium dense, moist to wet
41.5 9
y poorly graded SAND with gravel,dense,wet
"o
10JIGay poorly ggraded GRAVEL with silt and sand,dense,saturated, heavy
10.8 page at 10', 12%fines
11ay poorly graded SAND with gravel,dense,saturated
13.2 0
0 0 12
st pit terminated at 12.5 feet below existing grade. Groundwater
epage encountered at 8.0 & 10.0 feet during excavation.
I I
i
j
Test Pit Log
" 1 ' Earth Consultants Inc. Consumer Connection Office Building
m ��II VGA
/Al�l'�����L��� Gco�ctlinfcal F�igincers.GCobgUiss EfivironmeMal Sicnrbis Renton, Washington
1-7
la4Proj. No. 8342 Dwn. GLS Date July'98 Checked MGM Date 7/7/98 Plate
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis an
judgment They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log
Test Pit Log
_T
Project Name: Sheet of
Consumer Connection Office Building 1 1
Job No. Logged by: __7Date: Test Pit No.:
8342 MGM 6/23/98 TP-4
Excavation Contactor. Ground Surface Elevation:
Evans Brothers ±394'
Notes:
Surface Conditions: Depth of Topsoil & Duff 5":tall grass
W �111 o ,, 1-4 rn o
04 U
a) 44 ro Co
4 rn Q rn
SP-SM FILL: Brown poorly graded SAND with silt and gravel, loose, moist
1
2 SM FILL: Dark brown silty SAND, loose, moist
3 -contains bottles and concrete rubble
28.6 r
a GP-GM Brown poorly graded GRAVEL with sand, medium dense, moist
•. s -becomes dense, abundant cobbles
•
-becomes gray
9.1 7 -4% fines
o
a SP-SM Gray poorly graded SAND with silt,dense,wet
9
-moderate seepage at 10'along top of silt
10
ML Mottled brown SILT, medium dense, moist to wet
38.5
1 P-S Gray poorly graded SAND wit silt and gravel,dense,saturated
12
11.7
Test pit terminated at 12.5 feet below existing grade. Groundwater
seepage encountered at 10.0 feet during excavation.
I
i
I
I
I
m I
\ � I
rn
w
Test Pit Log
Earth ConSUltantS InC. Consumer Connection Office Building
�11 I � I. � Gto,ectu,n:a�Fngn,ecrs.Ceoloc¢itiss Fi,vlro"n,enlal ScSenlLsts Renton, Washington
a
H Proj. No, 8342 Dwn. GLS Date July'98 �Check�edMGM Date 7/7/98 Plate A5
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this loq
f
APPENDIX B
LABORATORY TEST RESULTS
E-8342
Earth Consultants, Inc.
'm Ift M IWI two i md i
SIEVE ANALYSIS HYDROMETER ANALYSIS
SIZE OF OPENING IN INCh1ES NUMBER OF MESH PER INCH U.S.STANDARD GRAIN SIZE IN McdM�
p - CO o O o o O
O ptD d M N - O O O
.-v d O cD O O O(0 coo O N O O O O O O O Q 0
o =� 10 0
co �� 10
— -_ 20
80 .�
m m
7J 30 :ar m 70 m
z
Ocn -I ao -�
-n 60 0
D
m 50
a70 50 mm
v = :T7
o _ 60
C - 40 =__ W
m -C
C 1 L _ 70 m
co 30 C)
n 80
20
n n _
CD _ — 90
10 -- -
-— - 100
n Z7 O0 CD (D CD OCD
O CO (D V M N �-- W lD O O O CDO O O O O O O O
� D O 0 0 N 0 O O coN V M GRAIN SIZE IN MILLIMETERS '
0 0 �) z FINES
p� � (D COARSE FINE COARSE MEDIUM FIN
n (n COBBLES GRAVEL SAND
Ft -
r• N
J U) Moisture LL PL
D
Boring or DEPTH USCS DESCRIPTION Content
(%)
' Ot D KEY Test Pit No. ft.
co LQ M
Ft H,
o n (n
U) O TP-1 3.5 SP-SM Brown poorly graded SAND with silt and gravel 10.5 -- --
r -- --
a ——— TP-3 10 GP-GM Gray poorly graded GRAVEL with silt and sand 10.8
�.
~
9.1
TP-4 7 GP Brown poorly graded GRAVEL with sand -- --
100
80
x 60
w
0
z
}
H t
40 —A-Line
g
C
20
C L-ML
0 20 `400 f0 80 100
LIQUID LIMIT
Natural
Key Boring/ Depth Soil Classification USCS L.L. P.L. PI. Water
Test Pit (ft) Content
• TP-2 8.5 Brown SILT ML 45 31 14 40
Atterberg Limits Test Data
Consumer Connection Office Building
�II F Iarth Consultants Inc. Renton, Washington
\\' I ' 1 Gc Cciiiic:l F>>Klx+ers.GYNc�Lss 6 Enfrcxrtx-ral Sck�ilss
Proj. No. 8342 Date July'98 Plate B2
DISTRIBUTION
E-8342
2 Copies CR Properties, LLC
p P
400 - 108th Avenue Northeast
Bellevue, Washington 98004
Attention: Mr. Gary Chatwin
2 Copies Barghausen Consulting Engineers, Inc.
18215 - 72nd Avenue South
t Kent, Washington 98032
Attention: Mr. Daniel Goalwin
i
i
i
r
Earth Consultants. Inc.
' •lob �813
GEOTECHNICAL ENGINEERING STUDY
PROPOSED CONSUMER CONNECTION
OFFICE BUILDING
WHITMAN COURT NORTHEAST
RENTON, WASHINGTON
' E-8342
1 July 17, 1998
t
PREPARED FOR
CR PROPERTIES, LLC
c �j,�vYWi-
Mitchell 6. McGinnis
Staff Geologist
1 6 R. CAtij�,
y�- F wns1�
y Z
s
Kyle R. Campbe J `
Manager of Geotechni
SxoNAL
EXPtR�S i1�(�ks
' Earth Consultants, Inc.
1805 - 136th Place Northeast, Suite 201
Bellevue, Washington 98005
(425) 643-3780
Earth Consultants Inc.
1 � Geotechnical Engineers,Ck'c>IoKists&Gm•ironmental Scientists
July 17, 1998 E-8342
CR Properties, LLC
400 - 108th Avenue Northeast
Bellevue, Washington 98004
Attention: Mr. Gary Chatwin
' Dear Mr. Chatwin:
We are pleased to submit our report titled "Geotechnical Engineering Study, Proposed
Consumer Connection Office Building, Whitman Court Northeast, Renton, Washington." This
report presents the results of our field exploration, selective laboratory tests, and engineering
analyses. The purpose and scope of our study was outlined in our June 12, 1998 proposal.
Based on the subsurface conditions encountered at the site, it is our opinion the proposed
building may be supported using conventional spread footing foundation systems bearing on
competent native soils, competent existing fill, or new structural fill. Slab-on-grade floors may
be similarly supported.
1 We appreciate this opportunity to be service to you. If you have any questions, or if we can
be of further assistance, please call.
Respectfully submitted,
EARTH CONSULTANTS, INC.
r
Kyle R. Campbell, P.E.
1 Manager of Geotechnical Services
MGM/SDD/KRC/km1
1805- 136th Place N.E.,Suite 201, Bellevue,Washington 98005
Bellevue(425)643-3780 Seattle(206)464-1584 FAX(425)74-608-60 Tacoma(253)272-6608
TABLE OF CONTENTS
E-8342
PAGE
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Project Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
SITE CONDITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Surface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Subsurface . . . . . . . . . . . . . . . 2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Groundwater 3
Laboratory Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
DISCUSSION AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Site Preparation and General Earthwork . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Foundations , 5
Slab-on-Grade Floors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Seismic Design Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
' Excavations and Slopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Site Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Pavement Areas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
. . . . . . . . . . . . . . . . . . . . . . . . . .
Utility Support and Backfill . , , , , , , , . , , g
LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
. . . . . . . .
Additional Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
APPENDICES
Appendix A Field Exploration
Appendix B Laboratory Test Results
ILLUSTRATIONS
Plate 1 VicinityMap
P
Plate 2 Test Pit Location Plan
Plate 3 Utility Trench Backfill
Plate Al Legend
Plates A2 through A5 Test Pit Logs
Plate 131 Grain Size Analyses
Plate B2 Atterberg Limit Test Data
Earth Consultants, Inc.
1
' GEOTECHNICAL ENGINEERING STUDY
PROPOSED CONSUMER CONNECTION
OFFICE BUILDING
' WHITMAN COURT NORTHEAST
RENTON, WASHINGTON
E-8342
INTRODUCTION
General
This report presents the results of our geotechnical engineering study for the proposed
Consumer Connection Office Building in Renton, Washington. The general location of the site
is shown on the Vicinity Map, Plate 1 . The purpose of this study was to explore the
subsurface conditions at the site and based on the conditions encountered to provide specific
geotechnical recommendations for the proposed development.
' At the time our study was performed, the site, proposed building and our exploratory locations
were approximately as shown on the Test Pit Location Plan, Plates2.
tProject Description
We understand it is currently planned to develop the approximately 12,000 square foot
commercial lot with a one-story office supported on piers above a ground level parking area.
The proposed building will have a footprint of about forty-five (45) by one hundred twenty-five
(125) feet and will be constructed in the approximate center of the site.
The proposed building will be of wood-frame construction with the supports consisting of
cast-in-place concrete piers. On the lower level will be an elevator room with stairwell with
a slab-on-grade floor.
i We anticipate column loads of eighty (80) to one hundred (100) kips and slab-on-grade floor
■ loads of about one hundred fifty (150) pounds per square foot.
The building will be surrounded by asphalt paved parking and driveway areas. Vehicle traffic
will consist of passenger vehicles and occasional service trucks.
If any of the above design criteria are incorrect or change, we should be consulted to review
the recommendations contained in this report. In any case, ECI should be retained to perform
a general review of the final design.
i
1
Earth Consultants, Inc.
w
' GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 2
SITE CONDITIONS
Surface
The subject site is located on the east side of Whitman Court Northeast approximately one
hundred forty-five (145) feet south of the intersection of Northeast Sunset Boulevard and
' Whitman Court Northeast in Renton (see Plate 1, Vicinity Map). The subject property is
bordered to the west by Whitman Court Northeast, to the east by an undeveloped, densely
vegetated lot, to the south by an asphalt parking lot north of an existing apartment complex
and to the north by a parking lot south of an existing office building.
f
' The asphalt parking area located immediately north of the proposed building area is located
within an approximately forty (40) foot wide drainage easement. This drainage easement
contains an approximately thirty-six (36) inch diameter corrugated metal pipe that outlets to
a creek immediately northeast of the proposed building area.
The site is essentially flat, with little discernible elevation change across the site.
The site is vegetated with dense grass and localized brush.
1 Subsurface
Subsurface conditions were evaluated by excavating four test pits at the approximate
locations shown on Plate 2. Please refer to the Test Pit Logs, Plates A2 through A5, for a
more detailed description of the subsurface conditions encountered at each test pit location.
A description of field exploration methods is included in Appendix A. The following is a
' generalized description of the conditions encountered.
At our test pit locations, we encountered a surficial layer of topsoil and duff that was
approximately five to six inches thick. The topsoil and duff was characterized by its dark
brown color and the presence of organic material and abundant roots. This soil is not suitable
for use in support of foundations, slab-on-grade floors or pavements. In addition, it is not
suitable for use as structural fill, nor should it be mixed with material to be used as structural
fill.
Underlying the topsoil, we typically encountered four feet of loose fill comprised of silty sand,
and poorly graded sand with silt and gravel (Unified Soil Classification SM, and SP-SM,
respectively). A one and one-half foot thick layer of fill was encountered in Test Pit TP-2.
The fill was characterized by trace amounts of organic material, concrete rubble,
miscellaneous debris, and the loose consistency.
i
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 3
Underlying the fill, we encountered silty sand (SM), poorly graded sand with silt (SP-SM),
poorly graded gravel with silt and sand (GP-GM), silt (ML) and silty sand (SM). The soils
contained variable amounts of gravel and cobbles. The upper two to three feet of the
observed native soils were typically loose to medium dense with trace amounts of organic
debris. At two to three feet below grade, the soils typically became medium dense to
approximately nine feet below grade. Below nine feet, the observed soils were typically
' medium dense to dense to the maximum exploration depth of thirteen (13) feet below existing
grade.
Groundwater
f
Light to heavy seepage was encountered at the test pit locations. At each of the test pit
locations, perched groundwater seepage was observed at approximately eight to ten (10) feet
below grade. The seepage was observed entering the excavation along the top of an
approximately one foot thick silt layer observed in each of the test pits. The soils below the
silt layer were typically wet to saturated.
Based on anticipated excavation depths and due to depth of the observed groundwater
seepage, we do not anticipate significant seepage will be encountered in building or utility
excavations. However, the contractor should be prepared to address the potential for
groundwater seepage into excavations, especially deep utility excavations.
The contractor should also be aware that groundwater levels are not static. There will be
fluctuations in the groundwater level depending on the season, amount of rainfall, surface
water runoff, and other factors. Seepage levels and flow rates are typically higher in the
wetter winter months (typically October through May).
Laboratory Testing
Laboratory tests were conducted on several representative soil samples to verify or modify
the field soil classification and to evaluate the general physical properties and engineering
characteristics of the soils encountered. Visual field classifications were supplemented by
Atterberg Limit test data and grain size analyses on representative soil samples. Moisture
content tests were performed on all samples. The results of the laboratory tests performed
on specific samples are provided either at the appropriate sample depth on the individual test
pit logs or on a separate data sheet contained in Appendix B. It is important to note that
these test results may not accurately represent the overall in-situ soil conditions. Our
geotechnical recommendations are based on our interpretation of these test results and their
use in guiding our engineering judgement. ECI cannot be responsible for the interpretation of
these data by others.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 4
In accordance with our Standard Fee Schedule and General Conditions, the soil samples for
this project will be discarded after a period of fifteen days following completion of this report
unless we are otherwise directed in writing.
DISCUSSION AND RECOMMENDATIONS
1 General
Based on the results of our study, it is our opinion the site can be developed generally as
planned. Building support can be provided using conventional spread footing foundation
system bearing on competent native soil, competent existing fill, or new structural fill. The
existing fill was observed to be in a loose condition. If loose soils are encountered at the
footing or slab subgrade elevation, the subgrade soils should be compacted in-place to the
requirements of structural fill. It may be necessary to overexcavate excessively loose soils
' and replace them with structural fill. Slab-on-grade floors can be similarly supported.
This study has been prepared for specific application to this project only and in a manner
consistent with that level of care and skill ordinarily exercised by other members of the
profession currently practicing under similar conditions in this area for the exclusive use of CR
Properties, LLC and their representatives. No warranty, expressed or implied, is made. This
1 report, in its entirety, should be included in the project contract documents for the information
of the contractor.
' Site Preparation and General Earthwork
The proposed building area should be stripped and cleared of all surface vegetation, organic
' matter, and any other deleterious material. Based on the thickness of the topsoil and root
layers encountered at our test pit locations, we estimate a stripping depth of five to six
inches. Stripped materials should not be mixed with materials to be used as structural fill.
Following the stripping operation, the ground surface where structural fill, slabs or foundations
are to be placed should be observed by a representative of ECI. Proofrolling may also be
necessary to identify loose or soft areas.
The existing fill underlying the site is in a loose condition. If loose soils are encountered at
the footing or slab subgrade elevation, the loose soils should be compacted in-place to the
requirements of structural fill. Alternatively, the loose soils may be overexcavated and
replaced with structural fill. If adequate, in-place compaction cannot be accomplished the soil
should be removed and replaced with structural fill.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 5
Structural fill is defined as compacted fill placed under foundations, roadways, slabs,
pavements or other load-bearing areas. Structural fill under foundations should be placed in
horizontal lifts not exceeding twelve (12) inches in loose thickness and compacted to a
minimum of 90 percent of its laboratory maximum dry density determined in accordance with
ASTM Test Designation D-1557-91 (Modified Proctor). The fill materials should be placed at
or near their optimum moisture content. Fill under pavements and walks should also be
' placed in horizontal lifts and compacted to 90 percent of maximum density except for the top
twelve 0 2) inches which should be compacted to 95 percent of maximum density.
During dry weather, most soils which are compactible and non-organic can be used as
structural fill. Based on they results of our laboratory tests, the on-site soils at the time of our
exploration appeared to be near the optimum moisture content and should be suitable for use
iin their present condition as structural fill, provided the grading operations are conducted
during dry weather. However, laboratory testing indicates that some of the site soils have
more than five percent fines passing the No. 200 sieve. These soils will degrade if exposed
' to excessive moisture, and compaction and grading will be difficult if the soil moistures
increase significantly above their optimum conditions.
If the site soils are exposed to moisture and cannot be adequately compacted then it may be
necessary to import a soil which can be compacted. During dry weather, non-organic
1 compactible soil with a maximum grain size of six inches can be used. Fill for use during wet
weather should consist of a fairly well graded granular material having a maximum size of six
inches and no more than 5 percent fines passing the No. 200 sieve based on the minus
3/4-inch fraction. A contingency in the earthwork budget should be included for this
possibility.
' Foundations
Based on the encountered subsurface soil conditions, preliminary design criteria and assuming
' compliance with the preceding Site Preparation and Grading section, the proposed office
building may be supported on a conventional spread footing foundation system bearing on
competent native soil, competent existing fill, or new structural fill. The existing fill is in a
loose condition. If loose soil is encountered at the footing subgrade elevation, in-place
compaction will be necessary. Alternatively, the loose soils may be overexcavated and
replaced with structural fill.
For frost protection considerations, exterior foundation elements should be placed at a
minimum depth of eighteen (18) inches below final exterior grade. Interior spread foundations
' can be placed at a minimum depth of twelve (12) inches below the top of slab, except in
unheated areas, where interior foundation elements should be founded at a minimum depth
of eighteen (18) inches. Continuous and individual spread footings should have minimum
widths of eighteen 0 8) and twenty-four (24) inches, respectively.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 6
The foundations may be designed for an allowable soil bearing capacity of two thousand five
hundred (2,500) psf for competent native soil, competent existing fill, or structural fill.
Loading of this magnitude would be provided with a theoretical factor-of-safety in excess of
' three against actual shear failure. For short-term dynamic loading conditions, a one-third
increase in the above allowable bearing capacities can be used.
' For the above design criteria, total settlement of foundations is expected to be less than one
inch. Differential settlements are expected to be less than one-half inch. The majority of the
anticipated settlement should occur during construction as the dead loads are applied.
' Horizontal loads can be resisted by friction between the base of the foundation and the
f
' supporting soil and by passive soil pressure acting on the face of the buried portion of the
foundation. For the latter, the foundation must be poured "neat" against the competent
native soils, or backfilled with structural fill. For frictional capacity, a coefficient of .35 can
be used. For passive earth pressure, the available resistance can be computed using an
' equivalent fluid pressure of three hundred fifty (350) pcf. These lateral resistance values are
allowable values, a factor-of-safety of 1 .5 has been included. As movement of the foundation
element is required to mobilize full passive resistance, the passive resistance should be
neglected if such movement is not acceptable.
' Footing excavations should be observed by a representative of ECI, prior to placing forms or
rebar, to verify that conditions are as anticipated in this report.
Slab-on-Grade Floors
We anticipate slab-on-grade floors will be used in the stairway/elevator room at the ground
1 level.
Slab-on-grade floors may be supported on competent existing fill, competent native soil or on
' new structural fill. Where loose soil is encountered at the slab subgrade elevation, the loose
soil should be compacted to the previously discussed requirements for structural fill.
Disturbed subgrade soils should either be recompacted or replaced with structural fill.
Concrete slabs should be provided with a minimum of four inches of free-draining sand or
gravel. In areas where slab moisture is undesirable, a vapor barrier such as 6-mil plastic
membrane should be placed beneath the slab. The vapor barrier should be sealed at the
seams and care taken during construction not to damage it. Two inches of damp sand may
be placed over the membrane for protection during construction and to aid in curing of the
concrete.
Earth Consultants. Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 7
Seismic Design Considerations
The Puget Lowland is classified as a Seismic Zone 3 in the 1997 Uniform Building Code
(UBC). Earthquakes occur in the Puget Lowland with regularity, however, the majority of
these events are of such low magnitude they are not detected without instruments. Large
earthquakes do occur, as indicated by the 1949, 7.2 magnitude earthquake in the Olympia
' area and the 1965, 6.5 magnitude earthquake in the Midway area.
There are three potential geologic hazards associated with a strong motion seismic event at
this site: ground rupture, liquefaction, and ground motion response.
Ground Ruoture: The strongest earthquakes in the Puget Lowland are widespread, subcrustal
events, ranging in depth from thirty (30) to fifty-five (55) miles. Surface faulting from these
deep events has not been documented to date. Therefore, it is our opinion, that the risk of
ground rupture at this site during a strong motion seismic event is negligible.
Liquefaction: Liquefaction is a phenomenon in which soils lose all shear strength for short
periods of time during an earthquake. Groundshaking of sufficient duration results in the loss
' of grain to grain contact and a rapid increase in pore water pressure, causing the soil to
behave as a fluid. To have a potential for liquefaction, a soil must be cohesionless with a
grain size distribution of a specified range (generally sand and silt); it must be loose; it must
' be below the groundwater table; and it must be subject to sufficient magnitude and duration
of groundshaking. The effects of liquefaction may be large total and/or differential settlement
for structures founded in the liquefying soils.
In our opinion, the potential for liquefaction induced settlement at the site is minimal.
' Ground Motion Response: Based on the encountered soil conditions, it is our opinion soil
profile type Sp, Stiff Soil as defined in Table 16-J of the 1997 Uniform Building Code (UBC)
should be used to characterize the site soils.
Excavations and Slopes
' In no case should excavation slopes be greater than the limits specified in local, state and
Federal safety regulations. Based on the information obtained from our field exploration and
1 laboratory testing, the site soils expected to be encountered in excavations would be classified
as Type C by OSHA, and as such, temporary cuts greater than four feet in height should be
sloped at an inclination no steeper than 1 .5H:1 V. If slopes of this inclination, or flatter,
cannot be constructed, temporary shoring may be necessary. This shoring will help protect
against slope or excavation collapse, and will provide protection to workers in the excavation.
If temporary shoring is required, we will be available to provide shoring design criteria, if
requested.
Earth Consultants, Inc.
GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 8
' Permanent cut and fill slopes should be inclined no greater than 2H:1 V.
The above information has been provided solely as a service to our client. Under no
circumstances should the above information be interpreted to mean that ECI is assuming
responsibility for construction site safety or the contractor's activities; such responsibility is
not being implied and should not be inferred.
Site Drainage
Light to heavy groundwater seepage was encountered in our test pits at depths ranging from
eight to ten feet below grade. Due to the depth of the observed seepage, it does not appear
groundwater will present construction related issues, unless excavations extend to depths of
eight to ten feet.
However, if groundwater seepage is encountered during construction, the bottom of the
' excavation should be sloped to one or more shallow sump pits. The collected water can then
be pumped from these pits to a positive and permanent discharge, such as a nearby storm
drain. Depending on the magnitude of such seepage, it may also be necessary to interconnect
' the sump pits by a system of connector trenches. The appropriate locations of subsurface
drains, if needed, should be established during grading operations by ECI's representative at
' which time the seepage areas, if present, may be more clearly defined.
The site should be graded such that surface water is directed off the site. Water must not
' be allowed to stand in areas where foundations or slabs are to be constructed. During
construction, loose surfaces should be sealed at night by compacting the surface to reduce
the potential for moisture infiltration into the soils.
Pavement Areas
The adequacy of site pavements is related in part to the condition of the underlying subgrade.
To provide a properly prepared subgrade for pavements, the subgrade should be treated and
prepared as described in the Site Preparation and General Earthwork section of this report.
' This means at least the top twelve (12) inches of the subgrade should be compacted to 95
percent of the maximum dry density (per ASTM D-1557-91). It is possible that some localized
areas of soft, wet or unstable subgrade may still exist after this process. Therefore, a greater
thickness of structural fill or crushed rock may be needed to stabilize these localized areas.
Earth Consultants, Inc.
' GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 9
' The following pavement sections for driveway and parking areas can be used:
• Two inches of asphalt concrete (AC) over four inches of crushed rock base (CRB)
' material, or
• Two inches of AC over three inches of asphalt treated base (ATB) material.
• Four inches of Portland Cement Concrete (PCC).
All pavement materials should conform to WSDOT specifications. In our opinion, a Class B
asphalt mix should be used.
' If the PCC pavement section is used, the subgrade should be moistened prior to concrete
placement. The PCC pavement section can be constructed in general accordance with the
practices for construction of slab-on-grade floors. A thickened edge is recommended on the
' outside of the concrete pavement section. The concrete should achieve an average
compressive strength of 4,000 psi at 28 days.
' Utility Support and Backfill
' Based on the soil conditions encountered, the soils expected to be exposed by utility
excavations should provide adequate support for utilities.
' Utility trench backfill is a primary concern in reducing the potential for settlement along utility
alignments, particularly in pavement areas. It is important that each section of utility line be
adequately supported in the bedding material. The material should be hand tamped to ensure
' support is provided around the pipe haunches. Fill should be carefully placed and hand
tamped to about twelve inches above the crown of the pipe before heavy compaction
equipment is brought into use. The remainder of the trench backfill should be placed in lifts
' having a loose thickness of less than twelve inches. A typical trench backfill section and
compaction requirements for load supporting and non-load supporting areas is presented on
Plate 3.
' LIMITATIONS
' Our recommendations and conclusions are based on the site materials observed, selective
laboratory testing and engineering analyses, the design information provided to us by the
client, and our experience and engineering judgement. The conclusions and recommendations
' are professional opinions derived in a manner consistent with that level of care and skill
ordinarily exercised by other members of the profession currently practicing under similar
conditions in this area. No warranty is expressed or implied.
Earth Consultants, Inc.
' GEOTECHNICAL ENGINEERING STUDY
CR Properties, LLC E-8342
July 17, 1998 Page 10
The recommendations submitted in this report are based upon the data obtained from the test
pits. Soil and groundwater conditions between test pits may vary from those encountered.
The nature and extent of variations between our exploratory locations may not become
evident until construction. If variations do appear, ECI should be requested to reevaluate the
recommendations of this report and to modify or verify them in writing prior to proceeding
with the construction.
' Additional Services
' As the geotechnical engineer of record, ECI should be retained to perform a general review
of the final design and specifications to verify the earthwork and foundation recommendations
have been properly interpreted and implemented in the design and in the construction
' specifications.
' ECI should also be retained to provide geotechnical services during construction. This is to
observe compliance with the design concepts, specifications or recommendations and to allow
design changes in the event subsurface conditions differ from those anticipated prior to the
' start of construction. We do not accept responsibility for the performance of the foundation
or earthwork unless we are retained to review the construction drawings and specifications,
and to provide construction observation and testing services.
Earth Consultants, Inc.
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Earth Consudtants, Inc.
Ge.technical Engineers,Geologists&Environmental Scientists
Reference: Vicinity Map
King County Map 626 Consumer Connection Office Building
By Thomas Brothers Maps Renton, Washington
Dated 1998
Drwn. GLS Date June '98 Proj. No. 8342
Chocked MGM Date 7/1/98 Plate 1
I I
I I
I I
Existing
I Wood Fiame !
Office Bldg. I
I
I I Approximate Scale
I I
q 0 20 40 80ft.
LEGEND
c
nE �-
TP-1 -!- Approximate Location of
' 5 ECI Test Pit, Proj. No.
E-8342, June 1998
' ! xAI I Proposed Building
(t I� Creek r————
! w. nI I i Existing Building
' Z _ iJ 1 Subject Site
_ I TP-1�
' 2 ITP-I Proposed ! Existing Asphalt Parking
T ! Building ! IMYI.011-'HLII;�� Lot
! With Parking
Below
! I
t
t i
�TP-3 Earth Consultants, Inc.
' t Geotechnical Engineers,Geologists 6 Environmental Scientists
TP-2: Test Pit Location Plan
' t Consumer Connection Office Building
! , Renton, Washington
' — _ — —i Drwn. GLS Date June '98 Proj. No.8342
Checked MGM Date 72/98 Plate 2
1
Non-Load Supporting Floor Slab or
Areas Roadway Areas
- �° ° ° Varies
°
° °
a 0
0
0
- 95 0
- �o p' o•o
' 95 1 Foot Minimum
Backfill
80.
0
Varies
PIPE
..0. O• •�vo: o
.0. .0.04. V.
• ° do•
° 0 0..
.d o p 0 Varies
Bedding °o•o. .°^0° e °.?•d ;.
�.o.'•.00'40:.• oaf• ; •°o' oo.•.
o pOl ooO °o!•�8!°O D�o �0 Q0 Cr
p• O .• O 0 O e'O. .00o4 O•o .Q°o
°•�O..oOa•o Qo •po• ,o;O a:'•o0 .°b ,,o
LEGEND:
' Asphalt or Concrete Pavement or Concrete Floor Slab
x 1
o. ° o°.
' . o ° °•°. Base Material or Base Rock
Back-fill; Compacted On-Site Soil or Imported Select Fill
Material as Described in the Site Preparation of the General
' Earthwork Section of the Attached Report Text.
95 Minimum Percentage of Maximum Laboratory Dry Density as
Determined by ASTM Test Method D 1557-78 (Modified Proctor),
Unless Otherwise Specified in the Attached Report Text.
' Bedding Material; Material Type Depends on Type of Pipe and
'°ao.00p Laying Conditions. Bedding Should Conform to the Manufacturers
Recommendations for the Type of Pipe Selected.
TYPICAL UTILITY TRENCH FILL
Earth Consultants Inc. Consumer Connection Office Building
C^Xceh'"''F� 'SISaFn�i� raiSc tL'AS Renton, Washington
Proj. No. 8342 Drwn. GLS Date July 198 Checked MGM Date 7/17/98 Plate 3_j
IMPORTANT INFORMATION
ABOUT YOUR
GEOTECHNICAL ENGINEERING REPORT
More construction problems are caused b site subsur- technical engineers who then render an opinion about
P Y
face conditions than any other factor. As troublesome as overall subsurface conditions, their likely reaction to
subsurface problems can be, their frequency and extent proposed construction activity, and appropriate founda-
have been lessened considerably in recent years, due in tion design. Even under optimal circumstances actual
large measure to programs and publications of ASFE/ conditions may differ from those inferred to exist,
The Association of Engineering Firms Practicing in because no geotechnical engineer, no matter how
the Geosciences. qualified,and no subsurface exploration program, no
The following suggestions and observations are offered matter how comprehensive, can reveal what is hidden by
earth, rock and time. The actual interface between mate-
cost-overruns and other costly headaches that can
' to help you reduce the geotechnical-related delays, vials may be far more gradual or abrupt than a report
indicates. Actual conditions in areas not sampled may
occur during a construction project. differ from predictions. Nothing can be done to prevent the
unanticipated, but steps can be taken to help minimize their
A GEOTECHNICAL ENGINEERING impact. For this reason, most experienced owners retain their
REPORT IS BASED ON A UNIQUE SET geotechnical consultants through the construction stage, to iden-
tify variances, conduct additional tests which may be
' OF PROJECT-SPECIFIC FACTORS needed, and to recommend solutions to problems
A geotechnical engineering report is based on a subsur-
encountered on site.
face exploration plan designed to incorporate a unique SUBSURFACE,CONDITIONS
set of project-specific factors. These typically include:
the general nature of the structure involved, its size and CAN CHANGE
configuration; the location of the structure on the site
and its orientation; physical concomitants such as Subsurface conditions may be modified by constantly-
access roads, parking lots, and underground utilities, changing natural forces. Because a geotechnical engi-
and the level of additional risk which the client assumed neering report is based on conditions which existed at
by virtue of limitations imposed upon the exploratory the time of subsurface exploration,construction decisions
program. To help avoid costly problems, consult the should not be based on a geotechnical engineering report whose
' geotechnical engineer to determine how any factors adequacy may have,been affected by time. Speak with the geo-
which change subsequent to the date of the report may technical consultant to learn if additional tests are
affect its recommendations. advisable before construction starts.
Unless your consulting geotechnical engineer indicates Construction operations at or adjacent to the site and
otherwise, your geotechnical engineering report should not natural events such as floods,earthquakes or ground-
be used: water fluctuations may also affect subsurface conditions
.When the nature of the proposed structure is and, thus, the continuing adequacy of a geotechnical
changed, for example, if an office building will be report.The geotechnical engineer should be kept
erected instead of a parking garage,or if a refriger- apprised of any such events,and should be consulted to
ated warehouse will be built instead of an unre- determine if additional tests are necessary.
frigerated one:
.when the size or configuration of the proposed GEOTECHNICAL SERVICES ARE
structure is altered; PERFORMED FOR SPECIFIC PURPOSES
.when the location or orientation of the proposed' AND PERSONS structure is modified;
•when there is a change of ownership, or Geotechnical engineers' reports are prepared to meet
.for application to an adjacent site. the specific needs of specific individuals. A report pre-
' Geotechnical engineers cannot accept responsibility for problems pared for a consulting civil engineer may not be ade-
which may develop if they are not consulted after factors consid- quate for a construction contractor,or even some other
ered in their report's development have changed. consulting civil engineer. Unless indicated otherwise,
this report was prepared expressly for the client involved
and expressly for purposes indicated by the client. Use
MOST GEOTECHNICAL "FINDINGS" by any other persons for any purpose, or by the client
ARE PROFESSIONAL ESTIMATES for a different purpose, may result in problems. No indi-
vidual other than the client should apply this report for its
Site exploration identifies actual subsurface conditions intended purpose without first conferring with the geotechnical
only at those points where samples are taken, when engineer. No person should apply this report for any purpose
they are taken. Data derived through sampling and sub- other than that originally contemplated without first conferring
' sequent laboratory testing are extrapolated by geo- with the geotechnical engineer.
A GEOTECHNICAL ENGINEERING der the mistaken impression that simply disclaiming re-
REPORT IS SUBJECT TO sponsibility for the accuracy of subsurface information
always insulates them from attendant liability. Providing
MISINTERPRETATION the best available information to contractors helps pre-
Costly problems can occur when other design profes- vent costly construction problems and the adversarial '
sionals develop their plans based on misinterpretations attitudes which aggravate them to disproportionate
of a geotechnical engineering report. To help avoid scale.
these problems, the geotechnical engineer should be READ RESPONSIBILITY
retained to work with other appropriate design profes-
sionals to explain relevant geotechnical findings and to CLAUSES CLOSELY
review the adequacy of their plans and specifications
relative to geotechnical issues. Because geotechnical engineering is based extensively '
on judgment and opinion, it is far less exact than other
design disciplines. This situation has resulted in wholly
unwarranted claims being lodged against geotechnical
BORING LOGS SHOULD NOT BE consultants.To help prevent this problem,geotechnical '
engineers have developed model clauses for use in writ-
SEPARATED FROM THE ten transmittals.These are not exculpatory clauses
ENGINEERING REPORT designed to foist geotechnical engineers' liabilities onto
someone else. Rather, they are definitive clauses which
Final boring logs are developed by geotechnical engi- identify where geotechnical engineers' responsibilities
neers based upon their interpretation of field logs begin and end. Their use helps all parties involved rec-
(assembled by site personnel)and laboratory evaluation ognize their individual responsibilities and take appro- '
of field samples. Only final boring logs customarily are priate action. Some of these definitive clauses are likely
included in geotechnical engineering reports.These logs to appear in your geotechnical engineering report,and
should not under any circumstances be redrawn for inclusion in you are encouraged to read them closely.Your geo-
architectural or other design drawings, because drafters technical engineer will be pleased to give full and frank ,
may commit errors or omissions in the transfer process. answers to your questions.
Although photographic reproduction eliminates this
problem,it does nothing to minimize the possibility of OTHER STEPS YOU CAN TAKE TO
contractors misinterpreting the logs during bid prepara-
tion.When this occurs,delays,disputes and unantici- REDUCE RISK
pated costs are the all-too-frequent result. Your consulting geotechnical engineer will be pleased to
To minimize the likelihood of boring log misinterpreta- discuss other techniques which can be employed to mit- ,
tion, give contractors ready access to the complete geotechnical igate risk. In addition,ASFE has developed a variety of
engineering report prepared or authorized for their use. materials which may be beneficial. Contact ASFE for a
Those who do not provide such access may proceed un- complimentary copy of its publications directory.
Published by '
THE ASSOCIATION
OF ENGINEERING FIRMS ,
PRACTICING IN THE GEOSCIENCES
8811 Colesville Road/Suite G 106/Silver Spring, Maryland 20910/(301) 565-2733
0788/3M '
AdAPPENDIX A
m MO i m m mom m m r
1
' APPENDIX A
FIELD EXPLORATION
1 E-8342
1 Our subsurface exploration was performed on June 23 199
8. The subsurface conditions at
1 the site were explored by excavating four test pits to a maximum depth of thirteen (13) feet
below existing grade. The test pits were excavated by Evans Brothers subcontracted to ECI,
using a rubber-tire backhoe.
1 Approximate test pit locations were determined by pacing from features as shown on the site
map provided by the client. Test pit elevations were determined relative to each other. The
1 locations and elevations of the test pits should be considered accurate only to the degree
implied by the method used. These approximate locations are shown on the Test Pit Location
Plan, Plate 2. ,
1 The field exploration was continuously monitored by a geologist from our firm who classified
the soils encountered, maintained a log of each test pit, obtained representative samples, and
1 observed pertinent site features. All samples were visually classified in accordance with the
Unified Soil Classification System which is presented on Plate Al , Legend. Logs of the test
pits are presented on Plates A2 through A5. The final logs represent our interpretation of the
' field logs and the results of the laboratory examination and tests of field samples. The
stratification lines on the logs represent the approximate boundaries between soil types. In
actuality, the transitions may be more gradual. Representative soil samples were placed in
1 closed containers and returned to our laboratory for further examination and testing.
1
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1
Earth Consultants, Inc.
' GRAPH LETTER
MAJOR DIVISIONS SYMBOL SYMBOL TYPICAL DESCRIPTION
Gravel e e e
GW Weil-Graded Gravels, Gravel-Sand
And Clean Gravels Q Q G gW Mixtures, Little Or No Fines
Gravelly (little or no fines) M
Coarse Soils . , ; GP Poorly-Graded Gravels,Gravel-
Grained gp Sand Mixtures, Little Or No Fines
Soils More Than GM Silty Gravels,Gravel-Sand-
50% Coarse Gravels With gm Silt Mixtures
' Fraction Fines(appreciable ZIAT�
Retained On amount of fines) GC Clayey Gravels,Gravel-Sand-
No. 4 Sieve gC Clay Mixtures
Sand •o 00 'a SW Well-Graded Sands, Gravelly
' And Clean Sand o �e o SW Sands, Little Or No Fines
Sandy (little or no fines)
More Than ' SP Poorly-Graded Sands, Gravelly
Soils 4"; AQ?;?f` S
50% Material Sands, Little Or No Fines
;;lE::>..;::.>:? �(>� p
Larger Than More Than
No.200 Sieve 50% Coarse SM Silty Sands, Sand- Silt Mixtures
Size Sands With Snl
' Fraction Fines(appreciable
Passi
Seveng No 4 amount of fines) SC Clayey Sands, Sand Clay Mixtures
SC
{ ML Inorganic Silts&Very Fine Sands,Rock Flour,Silty-
' ml Clayey Fine Sands;Clayey Silts w/Slight Plasticity
Fine Silts CL Inorganic Clays Of Low To Medium Plasticity,
Grained Arid Liquid LimitNO"
Soils Clays Less Than 50 CI Gravelly Clays, Sandy Clays, Silty Clays, Lean
Organic Silts Arnf Organic
I I I I I OI Silty Clays Of Low Plasticity
MH Inorganic Silts, Micaceous Or Diatomaceous Fine
More Than Mill Sand Or Silty Soils
50% Material Silts
Smaller T-han And Liquid Limit CH Inorganic Clays Of High
No.200 Sieve Clays Greater Than 50 Ch Plasticity, Fat Clays.
Size
OH Organic Clays Of Medium To High
oh Plasticity, Organic Silts
r---pt
Peat, Humus, Swamp Soils
Highly Organic Soils �� With High Organic Contents
' Topsoil ' y 4 Humus And Duff Layer
Fill Highly Variable Constituents
The discussion in the text of this report is necessary for a proper understanding of the nature
of the material presented in the attached logs.
DUAL SYMBOLS are used to indicate borderline soil classification.
C TORVANE READING,tsf I 2"O.D. SPLIT SPOON SAMPLER
qu PENETROMETER READING,tsf
W MOISTURE,%dry weight 24' I.D. RING OR SHELBY TUBE SAMPLER
P SAMPLER PUSHED
SAMPLE NOT RECOVERED WATER OBSERVATION WELL
' pcf DRY DENSITY, lbs. per cubic ft.
LL LIQUID LIMIT, % 4 DEPTH OF ENCOUNTERED GROUNDWATER
PI PLASTIC INDEX DURING EXCAVATION
1 I SUBSEQUENT GROUNDWATER LEVEL W/DATE
Earth Consultants Inc. LEGEND
' (a r na l u ui ul l ingi,a rr�.lw.r,ki};isls 6 I nvin"n,"r n.d x w nlisls
Proj. No. 8342 Date July'98 Plate Al
Test Pit Log
Project Name: Sheet of
Consumer Connection Office Building 1 1
' Job No. Logged by: Date: Test Pit No.:
8342 MGM 6/23/98 TP-1
JExcavation Contactor: Ground Surface Elevation:
' Evans Brothers ±390'
Notes:
w o o Surface Conditions: Depth of Topsoil & Duff 5"
1 �4 Q (Z UD
(0%) 4 r
V) U)
SP-SM FILL: Brown poorly graded SAND with silt and gravel, loose, moist
' 1
2 -abundant roots to 4'
' -trace concrete rubble
3
10.5 4 -12% fine
P-G Brown poorly graded GRAVEL with silt and sand, loose, moist
a' S -abundant cobbles
' s SP-SM Gray poorly graded SAND with silt, medium dense,wet
o ° 7
20.4 8 -moderate seepage at 8'
ML Mottled brown SILT, medium dense, moist
4o.s I
s SP-SIVI Gray poorly graded SAND with silt and gravel, medium dense,saturated
0
b 10
-caving
' 10.2
11
b
o 12
13 Test pit terminated at 13.0 feet below existing grade. Groundwater
seepage encountered at 8.0 feet during excavation.
NOTE: Elevation estimated from 1983 U.S.G.S. Bellevue South
' Topographic Map.
m
h
w
0 Test Pit Log
' � , Fafth Consultants Inc. Consumer Connection Office Building
M co GeoW.-m,icWEnghxtremGeo+ogkus&Envimnnw nvWsck_nnsts Renton, Washington
a
�
Proj.No. 8342 Dwn. GLS Date July'98 Checked MGM Date 7/7/98 Plate A2
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log.
' Test Pit Log
Project Name: Sheet of
Consumer Connection Office Building
' Job No. Logged by: Date: Test Pit No.:
8342 MGM 6123/98 TP-2
Excavation Contactor: Ground Surface Elevation:
' Evans Brothers ±390'
Notes:
w � o U) o surface conditions: Depth of Topsoil & Duff 5":tall grass
' R. U
(%) b Q N U
En U)
' SM FILL: Dark brown silty SAND, loose, moist
1
-abundant roots,trace concrete debris
2 SM Reddish brown silty SAND, medium dense, moist
17.6 3 -trace charred wood fragments
-small roots,trace gravel
• 4 SP-SM Brown poorly graded SAND with silt, medium dense, moist
5 -contains gravel
v
s
-grades to gray
7
' 21.6 C s -heavy seepage at 8' along contact with silt
°
00
LL=45 PL=31 40.0 ML Mottled brown SILT, medium dense, moist
PI=14 9
o , 10 SP-SN Gray poorly graded SAND with silt and gravel, medium dense,wet
' 14.4 °•°
11
_o
12 -becomes dense
Test pit terminated at 12.5 feet below existing grade. Groundwater
seepage encountered at 8.0 feet during excavation.
co
a,
a,
h
a,
Test Pit Log
' N Earth Consultants Inc.
� Consumer Connection Office Building
M Ceotectv�"Fn Ceob
m `�'"''°"" "'�'$Cen' Renton,Washington
' a
H
own.Proj. No. 8342 GLS Date July'98 Checked MGM Date 7/7/98 Plate A3
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log.
' Test Pit Log
Project Name: Sheet of
Consumer Connection Office Building 1 1
Job No. Logged by: Date: Test Pit No.:
8342 MGM 6/23/98 TP-3
Excavation Contactor: Ground Surface Elevation:
Evans Brothers ±390'
' Notes:
,c - surface conditions: Depth of Topsoil & Duff 5":tall grass
W _ o rl m o
104 04+�
M Q M �D
� rn rn to
P-S FILL: Brown poorly graded SAND with silt, loose, moist
1 -abundant roots to 4'
9.0 -trace concrete debris
' 2
-metal wire in sidewall
3 -becomes reddish brown
76.1 4 ML Dark brown SILT with sand, loose,wet, contains organics, possible old
s P-S Brown poorly graded SAND with silt, medium dense, moist
o . .
° o
s
o
° O 7
$ -light see a e at 8' alongcontact
ML Mottled brown SILT, medium dense, moist to wet
' 41.5
9
P-S Gray poorly graded SAND with gravel,dense,wet
i
10
P-G Gray poorly graded GRAVEL with silt and sand,dense,saturated, heavy
10.8 seepage at 10', 12% fines
' 11
P-S Gray poorly graded SAND with gravel,dense,saturated
13.2
12
Test pit terminated at 12.5 feet below existing grade. Groundwater
seepage encountered at 8.0 & 10.0 feet during excavation.
Co
a,
rn
h
Test Pit Log
' Earth Consultants Inc. Consumer Connection Office Building
I GeotechnicalEngfV IS,GeOIOMStS&Fsvfronmentalsckntism Renton, Washington
' a
w Proi.No. 8342 Dwn. GLS Date July'98 Checked MGM Date 717/98 Plate A4
H
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log.
' Test Pit Log
Project Name: Sheet of
Consumer Connection Office Building 1 1
' Job No. Logged by: Date: Test Pit No.:
8342 MGM 6/23/98 TP-4
Excavation Contactor: Ground Surface Elevation:
Evans Brothers f394'
' Notes:
W U o � 1-4 Surface Conditions: Depth of Topsoil & Duff 5":tall grass
Q 4
a U)
m
� rn U)
P-S FILL: Brown poorly graded SAND with silt and gravel, loose, moist
' 1
2 SM FILL: Dark brown silty SAND, loose, moist
3
-contains bottles and concrete rubble
28.6
a GP-GA Brown poorly graded GRAVEL with sand, medium dense, moist
•. 5
•• s
� -becomes dense, abundant cobbles
7 -becomes gray
9.1 -4%fines
_o
8 SP-SIVI Gray poorly graded SAND with silt, dense,wet
g
10 -moderate seepage at 10'along top of silt
ML Mottled brown SILT, medium dense, moist to wet
' 38.5
11 SP-SM Gray poorly graded SAND wit silt and gravel,dense, saturated
0
11.7 °'°' 12
' Test pit terminated at 12.5 feet below existing grade. Groundwater
seepage encountered at 10.0 feet during excavation.
h
a
Test Pit Log
' Earth Consultants Inc. Consumer Connection Office Building
Geotecf ikaW Fnghreers,Geobosts R Environmental Sctentws
tt
co �. Renton, Washington
' a
H
Proj.No. 8342 Dwn. GLS Date July'98 Checked MGM Date 7/7/98 Plate AS
Subsurface conditions depicted represent our observations at the time and location of this exploratory hole,modified by engineering tests,analysis and
judgment. They are not necessarily representative of other times and locations.We cannot accept responsibility for the use or interpretation by others of
information presented on this log.
APPENDIX B
1
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1
1
t
t
APPENDIX B
' LABORATORY TEST RESULTS
iE-8342
1
1
i
1
1
i
1
Earth Consultants, Inc.
= m m = = m = = = w = = = = m m m
SIEVE ANALYSIS I HYDROMETER ANALYSIS
__ SIZE OF OPENING IN INCHES NUMBER OF MESH PER INCH U.S.STANDARD GRAIN SIZE IN MM
O
Na a m N w o cD o 0 0 00 00 00 0 0 0 o o `p� 0 0
z cD ct M N �n > ch �i N R N M 'd to tD W N O O O O O O 0 0
100
00
W 90
N
CTJ 20
p - 80
-� m D
m
r m 70 30 n
m m
z
r r Oz-1 40 �
U0 TI so n
" z O
-r
m 50 D
p W 50 N
-<
m
CD
� _ 40 so
m
= 30 70 m
co —i
2
CD
20 80
X
CCD
o
O in 10 90
m 1144+
n A00
-4
� 0 � °O O O O O O O O O 00 fD M N .- co co V M N '- 0 (D V C) N c' 00 tD V M N
-n O O O N tO a M N O O O O O O O O O O O
crt p D M N GRAIN SIZE IN MILLIMETERS '
p 0 Z
COBBLES COARSE
FINE COARSE MEDIUM FINE FINES
SAND
ct::E H, N
� w o m
J D Boring or DEPTH Moisture
~ O Z KEY 9 USCS DESCRIPTION o LL PL
t-h D Test Pit No. (ft.) Content (/0)
ct N'
0 0
�j m m
O TP-1 3.5 SP—SM Brown poorly graded SAND with silt and gravel 10.5 -- --
iv �
p---— TP-3 10 GP-GM Gray poorly graded GRAVEL with silt and sand 10.8
-- --
to r
~ ......... TP-4 7 GP Brown poorly graded GRAVEL with sand 9.1 -- --
100
80
' w 60
0
z_
}
� f
' U
�
40 ``—A-Line
g
1
c
20 �
' CL-ML OL
' 0 20 40 SO 80 100
LIQUID LIMIT
Natural
Key Boring/ Depth Soil Classification USCS L.L. P.L. PI. Water
' Test Pit (ft.) Content
' • TP-2 8.5 Brown SILT ML 45 31 14 40
' Atterberg Limits Test Data
Earth Consultants IncFNProCj
. sumer Connection Office Building
Renton, Washington
o. 8342 Date July'98 Plate B2
' DISTRIBUTION
E-8342
' 2 Copies CR Properties, LLC
400 - 108th Avenue Northeast
Bellevue, Washington 98004
' Attention: Mr. Gary Chatwin
' 2 Copies Barghausen Consulting Engineers, Inc.
18215 - 72nd Avenue South
Kent, Washington 98032
Attention: Mr. Daniel Goalwin
r .
Earth Consultants, Inc.
1 P% 032305-—Q?8.!
v Shod PIat'(SHPL•# .
REQUEST FOR PRO=it PrelinL Plat (PP# �
CAG# )
To: Technical Services Date OC' o kr c r4(4e, WO# 7F4/41� Green# ----------------
From: Plan Review/Project Manager
Project Name C.
r t%Pe ti� !E'S / 4 ,L9 ��'fl r ]�)1 3 r7 Co i-i_1r'1 Kr--,(70 characters rnax) •
Description of Project: G I` I C �- i4_e ci i '7�r
Circle Size of Waterline: 8" 10" 12" Circle One: New or Extension
Circle Size of Sewerline: 8" 10" 12" Circle One: New or Extension
Circle Size of Store- ne: 12" 15" 18" 24" Circle One: New or Extension
Address or Street Name(s) / .j/ f ��`h ,f f iYi �C Gr �`��1` /V C_
Dvlpr/Contractor/Owner Cnslt:: E C.- k1,j i t"1
(70 characters max)
&ma `fit-A `IF'o.��l
Check each discipline involved in Project Ltr Drwg #of sheets per discipline
Cam? C_ ' 1
❑ Trans-Storm l-C u,�er C.C_d ar �,��lr ❑ ❑
(Road way/Drainagc) (Off site improvcmcnts)(include basin name) (include TESC sheets)
❑ Transportation (Signalizatiorr.Channelizatioa.Lighting) Cl ❑
�! • `-
❑ Wastewater l �' C �'�( z;1,_ )` 4, ;�E; - ❑ ❑
Sanitary Sewer Main(include basin name) `t
C.4,
❑ Water (Mains.Valves.F�rydrants_'� ❑ Cl I L`'i, ) J �l tl._A.
_-- —
R (Include composite&Horizontal Cui Sheets)
❑ Suface Water ❑ ❑ �L /
Improvements (CIP NLY)(includc basin name)
TS Use Only — l ✓ /,�i t
1� - e