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REPORT
GEOTECHNICAL ENGINEERING SERVICES
BOEING LONGACRES PARK
RENTON, WASHINGTON
FOR
BOEING SUPPORT SERVICES
Geod1 Engineers
Consulting Engineers
and Geoscientists
January 23, 1991 Offices in Washington,
Oregon,and Alaska
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BE&C Engineers
P.O. Box 3797, MS 13-03
Seattle, Washington 98124-2207
Attention: Mr. Robert H. Wicklein, P.E.
We are pleased to submit 26 copies of our "Report of Geotechnical
Engineering Services, Boeing Longacres Park, Renton, Washington for Boeing
Support Services. "
The scope of our services is outlined in our proposal dated November 9,
1990. Our services were authorized by BE&C Agreement No. BECE 0050, Work
Order No. 90-8000.
During the course of our services, we have been in contact with you and
other members of your design team to discuss design issues and to provide
information and recommendations as our findings were developed.
It has been our pleasure to work with you on this project. If you have
any questions regarding the contents of this report or if we can be of `
further service, please contact us.
Yours very truly,
GeoEngineers, Inc.
Jon W. Koloski
Principal
NLT:JWK:cs
File No. 0120-090-BO2
GeoEngineers,Inc.
8410 154th Avenue N.E.
Redmond,WA 98052
Telephone(206)861-6000
Fax(206)861-6050
Printed on recycled paper.
T A B L E O F C O N T E N T S
+ INTRODUCTION Page I No.
SCOPE 2
SITE CONDITIONS 3
SURFACE CONDITIONS 3
SUBSURFACE CONDITIONS 5
CONCLUSIONS AND RECOMMENDATIONS 7
GENERAL 7
SEISMIC CONSIDERATIONS 8
Regional Seismicity 8
Liquefaction Potential 9
SITE PREPARATION AND EARTHWORK 10
Site Preparation 10
Structural Fill 11
Erosion Control 13
Fill Settlement 13
EXCAVATIONS 15
FOUNDATION SUPPORT 16
General 16
Axial Pile Capacity 16
Pile Downdrag 18
Lateral Pile Capacity 18
Pile Settlement 19
Pile Installation 19
Pile Testing Program 20
FLOOR SLAB SUPPORT 21
PRELOAD/SURCHARGE FILL 22
SUBGRADE WALLS 24
LATERAL RESISTANCE 25
PAVEMENTS 26
PERMANENT DRAINAGE CONSIDERATIONS 27
OTHER CONSIDERATIONS 28
LIMITATIONS 29
List of Figures
Figure No.
VICINITY MAP I
SITE PLAN 2
CROSS-SECTION A 3
i CROSS-SECTION B 4
RANGE OF ESTIMATED SETTLEMENTS 5
SETTLEMENT PLATE DETAIL 6
APPENDIX A
Page No.
FIELD EXPLORATIONS AND LABORATORY TESTING A-1
FIELD EXPLORATIONS A-1
LABORATORY TESTING A-2
List of Appendix A Figures
Figure No.
SOIL CLASSIFICATION SYSTEM A-1
KEY TO BORING LOG SYMBOLS A-2
LOG OF BORING A-3 through A-42
LOG OF MONITOR WELL A-43 through A-48
GRADATION CURVES A-49 and A-50
ATTERBERG LIMITS TEST RESULTS A-51
CONSOLIDATION TEST RESULTS A-52 through A-54
CONSOLIDATED DRAINED TRIAXIAL TEST DATA A-55 and A-56
APPENDIX B
Page No.
REPORT ON SOIL SAMPLE CORROSIVITY TESTING B-1 through B-21
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EXECUTIVE SUMMARY
INTRODUCTION
The Boeing Longacres Park will occupy the existing Longacres horse
racing facility in Renton, Washington. The current development concept
consists of building 14 to 18 office buildings across the site. Most of the
buildings will be two to four stories in height with total floor areas of
approximately 200,000 square feet each. As most of the buildings are in the
conceptual phase of planning, specific building locations, site grades, and
design loads were not known at the time this study was completed.
The overall scope of our study includes:
o Evaluating surface and subsurface soil and ground water conditions
by reviewing available information and drilling 19 additional
borings.
o Recommendations for site preparation, earthwork, and excavations.
o Recommendations for foundation support.
o Recommendations for support of slabs and pavements.
o Address the seismic considerations for the site and evaluate the
potential for liquefaction
SITE CONDITIONS
The project site is approximately rectangular in shape and is situated
on the floor of the Green River valley. The site is relatively level. The
existing main race track occupies the north-central portion of the site.
The grandstand buildings are situated west of the track, and most of the
horse barns are located east of the track. A remnant of an old channel of
the Green River is present across the south half of the race track.
Springbrook Creek flows along a portion of the east property line.
Portions of the site have been modified by minor regrading. Soil
conditions are relatively uniform across the site. Existing fill across the
site varies from silt or silty sand to construction debris to hay and
manure. Native surface deposits consist of loose sand and soft to medium
stiff silt underlain by medium dense to dense sand. The thickness of the
native upper deposits ranges across the site from about 15 to 35 feet. The
underlying medium dense to dense sand deposits extend to the depths explored
in the borings. One boring encountered a lower zone of loose sand and
medium stiff silt from a depth of about 46 to 70 feet.
Ground water levels were measured at depths of about 4 to 7 feet. We
anticipate that the ground water levels will fluctuate seasonally in
response to changes in precipitation and the level of the Green River.
CONCLUSIONS
It is our opinion that the site can be developed as planned. Due to
the presence of upper compressible fine-grained soils and loose granular
soils, we recommend that the proposed buildings be pile-supported. As
placement of fill or surface loads will result in settlements due to
consolidation of underlying soils, slabs may be supported on-grade provided
slab areas are preloaded to compensate for the weight of the slab, and that
slabs are not constructed until settlements due to fill are complete. Our
conclusions and recommendations are summarized as follows:
o Portions of the site are underlain by deposits of loose sand which
are susceptible to liquefaction during a sustained earthquake.
The effects of liquefaction include some reduction in the capacity
of piles and possible cracking of on-grade floor slabs.
o We recommend that any existing fill which contains organic matter
be removed from building areas, utility trenches and pavement or
other slab areas.
o The soils at the site are moisture sensitive and will become soft
when wet and disturbed. We strongly recommend that site
preparation and earthwork be performed during periods of extended
dry weather.
o Most of the on-site soils will be suitable for use in structural
fill only under very limited conditions due to their moisture
sensitivity. We anticipate that most of the fill required for
raising building grades will need to be imported.
o Placement of fill will result in settlement due to consolidation
of underlying compressible soils. The majority of settlement will
occur in three to five weeks. Some portions of the site will
require longer time for settlements to occur.
o We recommend that the buildings be pile supported due to the
presence of loose and soft deposits across the site. We expect
that augercast piles will be used, but have also included design
values for driven piles.
o Pile lengths will be on the order of 40 to 70 feet, depending on
the capacity required and on the depth to the medium dense sand.
o The main options for slab support are (1) support the slab no
higher than the existing grade after recommended preparation of
the subgrade (2) support the slab on a pad of structural fill
after allowing sufficient time for the fill to settle or
(3) structurally support the slab on piles.
o We recommend that for support of on-grade slabs, the slab area be
preloaded with additional fill to minimize postconstruction
settlement due to floor loads.
o We recommend delaying construction of utilities, pavements, and
other settlement-sensitive facilities until settlements due to
filling are complete.
o Due to the presence of fill with organic matter and native silt
and organic silt across the site, we recommend corrosion
protection be considered in the design of utilities.
REPORT
GEOTECHNICAL ENGINEERING SERVICES
BOEING LONGACRES PARK
RENTON, WASHINGTON
FOR
BOEING SUPPORT SERVICES
INTRODUCTION
This report presents the results of our geotechnical engineering
services for Boeing Longacres Park in Renton, Washington. The location of
the project site is shown on the Vicinity Map, Figure 1.
The site consists of about 215 acres located south of Interstate 405
and east of the West Valley Highway. The property has operated since 1933
as a horse racing facility and contains a grandstand, numerous parking
areas, support buildings, horse barns, the race track and a training track.
The Boeing Longacres Park will include about 14 to 18 office buildings two
to four stories in height, together with related streets, parking facilities
and buried utilities. Due to wetland considerations, buildings will not be
situated in the extreme southeast corner of the site, nor in most of the
infield of the main race track. However, an access road may extend through
the track infield.
At this time, the proposed buildings and other site development
features are in the conceptual phase of design. Most of the buildings will
have total floor areas of approximately 200,000 square feet each, with
column spacing on the order of 40 feet in each direction. An exception is
the planned CTFOS (Customer Training and Flight Operation Support) building.
This building will consist of three wings. Each wing will have dimensions
of about 250 feet by 300 feet. One wing of the building will house
settlement- and vibration-sensitive flight simulation equipment. Boeing is
currently planning to locate this building in the northeast portion of the
site.
As most of the buildings are in the conceptual phase of planning,
design loads and final site grades are not known at this time. We
anticipate that column loads may be on the order of 300 to 600 kips for two-
to four-story buildings. Existing site grades in building areas will be
raised 1 to 3 feet due to flooding considerations.
GeoEngineers has performed previous geotechnical studies for portions
of the site for the past owners of the track. An environmental site
assessment has been performed by Landau Associates, Inc.
SCOPE
The purpose of our services is to evaluate subsurface soil and ground
water conditions at the project site as the basis for our geotechnical
recommendations and design criteria identified in the Statement of Work
prepared by Boeing Support Services. Our specific scope of services
includes:
1. Review existing subsurface information from previous explorations
performed at or near the site by our firm and review available
subsurface information performed by others. We also reviewed
Volume 1 of a report dated August 31, 1990 by Landau Associates
for a site assessment study.
2. Further explore subsurface conditions by drilling 19 additional
borings.
3. Obtain samples from the borings at the direction of Boeing for
chemical testing, as requested.
4. Determine pertinent engineering characteristics of the foundation
soils from the results of laboratory tests performed on soil
samples obtained from the explorations.
5. Provide recommendations for site preparation and earthwork,
including assessment of the suitability of on-site soils for use
in engineered fills, recommended fill slopes, compaction criteria
and any special construction procedures due to special soil
characteristics.
6. Evaluate the magnitude of settlements due to filling or typical
floor loading and provide recommendations for preloading, as
appropriate.
7. Develop recommendations for subgrade excavations, including
allowable temporary cut slopes, shoring options and possible
dewatering requirements.
8. Provide recommendations for foundation support. Pile support is
anticipated for most of the structures, thus we have developed
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capacity-penetration relationships for appropriate types of pile
foundations, pile installation criteria and lateral pile
capacities.
9. Evaluate the magnitude of total settlements for selected pile
types and for typical column loading.
10. Provide recommendations for support of floor slabs, including
whether slabs can be supported on grade and a value for the
modulus of subgrade reaction.
11. Develop recommendations for subgrade or other retaining walls,
including design lateral soil pressures, passive pressures,
friction coefficients and drainage requirements.
12. Provide recommendations for support of pavements.
13. Provide the frost depth for the site.
14. Evaluate site ground water conditions and provide recommendations
regarding temporary and permanent drainage and erosion control
measures.
15. Address the seismic considerations for the site including a
discussion of earthquake conditions, the characteristic site
period and evaluating the potential for liquefaction across the
site.
16. Attend one to three meetings with Boeing representatives to
discuss the results of our study, as appropriate.
17. Prepare a written report containing our conclusions and recommen-
dations along with the supporting field and laboratory data.
Submit the report in draft form for review by Boeing prior to
issuing the final report.
SITE CONDITIONS
SURFACE CONDITIONS
The site is approximately rectangular in shape and is situated on the
floor of the Green River valley. The existing Green River channel is
located about 1,000 to 1,500 feet west of the west side boundary.
Springbrook Creek (also known as the P-1 Channel) borders a portion of the
northeast boundary of the site.
The site is relatively level. The main race track is situated in the
north-central portion of the parcel. The grandstand buildings are situated
on the ,west side of the track. Paved and unpaved parking areas are located
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between the track and the west property boundary, and between the south end
of the track and Southwest 27th Street, which enters the site from the east.
The main horse barn area is situated on the east side of the track, with a
smaller training track located east of the barns. A more detailed
description of the existing buildings is presented in the Landau report.
Two undeveloped areas are present within the site. An area between
Southwest 27th Street and the south boundary is undeveloped and mainly
consists of a grass-covered field. A small portion of this area has been
used to dispose of miscellaneous materials including soil, landscape waste
and construction debris. The southeast corner of this area is on the edge
of a large wetland which extends off-site to the east and south. The second
undeveloped area is situated north of the training track between the barns
and Springbrook Creek. This portion of the site has been used as a hay
field in the past and is currently vegetated with tall grass and scattered
brush.
A row of large poplar trees surrounds the north, east and south
perimeter of the main track; scattered cottonwood and other deciduous trees
are present across the site. The infield of the main track and the training
track consist of mowed grass.
An arc-shaped shallow channel is present across the south half of the
main race track infield. This depression is the remnants of an old channel
of the Green River. The channel remnant extends east through the barn area
and across the north infield of the training track to the P-1 Channel. In
addition, there is a combination natural and excavated swale/ditch across
the north infield of the main track and a shallow drain ditch around the
inside perimeter of the main track. During prolonged periods of rainfall,
standing water is present throughout the channel and ditch areas. Surface
water is typically not present across the remainder of the site except for
Springbrook Creek and in an area in the extreme southeast corner of the
site. In the past, we have observed a significant portion of the infield
and barn area to be flooded for a time after record-level storms.
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SUBSURFACE CONDITIONS
Subsurface soil and ground water conditions were explored by drilling
19 test borings at the locations shown in Figure 2. Locations of borings
we have performed for past studies for others are also shown. A description
of the field exploration and laboratory testing procedures and the logs of
the explorations are presented in the Appendix.
We have also reviewed existing subsurface information from previous
explorations performed at the site by our firm and by others. We have also
reviewed the subsurface information presented in the Landau report,
especially with respect to the character of existing fill encountered in the
test pits. In general, the subsurface conditions reported from these .
previous explorations are consistent with those encountered in the current
explorations.
Most of the site is either covered with sod, crushed rock surfacing or
asphalt paving. In general, sod is present only in the infield of the main
and training track and across the undeveloped areas north of the training
track and south of Southwest 27th Street. As described in the Landau
report, most of the site has undergone some grading or filling in the past.
The areas which have received significant amounts of fill include the
training track and infield, a portion of the field north of the training
track and the undeveloped area south of Southwest 27th Street. Based on our
knowledge of the track construction, up to 9 feet of fill is present within
the north half of the main track embankment, with minor amounts of fill
along the outside edge of the south half. In addition, a former channel of
the Green River appears to have meandered through the site, extending from
the south boundary north to the infield of the race track, and then east
close to the training track and off site. The old channel has not been
filled in the infield of the main track, but has been filled in to the east,
and was probably filled to the south prior to development of the race track.
Sixteen of the nineteen borings did not encounter fill at the first
sample depth (2.5 feet) the exceptions being Borings 2, 3, and 6. The fill
observed in the borings generally consists of excavated and/or reworked
native silt and silty sand which is similar in character to the native
soils; some imported granular soils or crushed rock was noted. Thus, fill
may be present at other boring locations either above the first sampling
interval or was sampled but not recognized as fill due to the absence of
hay, wood, debris, or other fill indicators. Fill containing hay, manure,
5
wood, asphalt and other debris was encountered in many of the test pits
accomplished by Landau. In addition, we believe that the practice track
area and a portion of the field to the north were manure disposal sites.
The fill and remainder of the site are underlain by an upper unit of
interlayered silt, sandy silt, silty sand and sand with variable quantities
of organic matter and lenses of peat. These soils are typical overbank
flood deposits and flood-plain organics (peat) , underlain or interbedded
with marine (estuarine) organic silt and fluvial sand. The thickness of
these upper soft and loose deposits ranges across the site from about 15 to
35 feet. In general, the thickness of silt encountered in the borings was
less than 10 feet, although Borings 6, 10, 13, 15 and 16 encountered 15 to
25 feet of silt and organic silt. These soils are generally moderately to
highly compressible and will consolidate when subjected to new loads.
The upper deposits are underlain by medium dense to dense sand. Thin
deposits of gravelly sand to sandy gravel were encountered in some of the
borings. These soils are also loose to moderately dense having been
deposited as river channel bedload. Most of the borings encountered marine
shell fragments in the sand below a depth of 40 feet. The presence of
shells indicate that the deposits below this depth were deposited in an
estuarine environment during the postglacial infilling of the Green River
valley. Borings 4, 16 and 19, situated at the south end of the site,
encountered a 5-foot-thick layer of medium stiff silt at a depth of 50 to
60 feet. All of the borings terminated in medium dense to dense sand or
gravel.
Somewhat inconsistent soil conditions were encountered in Boring 18.
At this location, interbedded medium stiff clay and loose sand are present
from a depth of about 46 to 70 feet and loose silty sand from 70 to 80 feet.
The clay is moderately compressible. Dense sand and gravel was encountered
below a depth of 80 feet in this boring.
Two cross sections have been developed to illustrate the generalized
subsurface conditions at the site. These cross sections are presented in
Figures 3 and 4.
Ground water levels were observed in the borings between a depth of 5
to 10 feet during drilling, with most of the borings encountering ground
water at a depth of about 6 feet. Monitor wells were installed in or next
to Borings 1, 3, 4, 11, 12 and 16 to facilitate future monitoring of ground
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water levels. The ground water levels were measured on January 4, 1991 at
depths of about 4 to 6�i feet. These ground water levels are relatively
consistent with those previously measured by Landau.
CONCLUSIONS AND RECOMMENDATIONS
GENERAL
Based on the results of our explorations, it is our opinion that
geotechnical conditions at the project site are compatible with the proposed
development.
Due to the presence of the weaker, compressible fine-grained soils and
loose granular soils which are susceptible to liquefaction at shallow depth,
we recommend that the proposed buildings be pile-supported. Depending on
the design building loads, we anticipate that the piles will extend to
depths of about 40 to 70 feet to be supported in the medium dense to dense
sand deposits. Pile lengths may be longer for buildings situated in the
southwestern portion of the site due to deeper deposits of silt in this
area.
Although final grades have not yet been established, we believe that
existing grades in building areas will be raised 2 to 3 feet by filling.
Placement of fill and building slab loads will cause consolidation of the
underlying soils. To minimize settlement of ground level slabs, three
support options are feasible: (1) support the slab such that the slab is
at or below existing grades, (2) support the slab on a pad of structural
fill after preloading the site to compensate for slab loads and allowing
sufficient time for consolidation under the permanent and temporary fill
loads to occur, or. (3) structurally (i.e. , pile) support the slab.
We expect that option (1) above is not widely applicable due to
requirements for flood protection.
The time required for settlements to occur will vary across the site
due to variations in the density and thickness of the sand and silt layers.
A surcharge program, i.e. , placing additional fill, could reduce the time
required for the settlement to occur. Unless new fill placed in building
areas is allowed to completely settle prior to installation of piles,
downdrag forces will develop on the piles.
In addition, portions of the site contain surficial amounts of fill
with organic matter (hay, wood, etc. ) . Prior to construction of each
building, we recommend that test pits be accomplished across each building
7
area to evaluate whether such fill is present. Where fill with organic
material is present in building areas, we recommend that this fill be
removed and replaced with structural fill, or the slab be pile supported.
The recommendations presented in this report are general in nature as
specific building locations and loads were not finalized at the time this
report was completed. We anticipate that additional consultation will be
necessary to provide more building-specific recommendations as each building
location and configuration is determined. We recommend that review of
specific building locations, grades and slab loads be accomplished as far
in advance as possible to allow for preloading without delaying construction
schedules. As discussed below, we recommend that additional explorations
be accomplished in the vicinity of Boring 18 after building locations are
finalized. Additional borings may also be required at other building sites,
depending on the design requirements and the proximity of relevant
explorations.
SEISMIC CONSIDERATIONS
Regional Seismicity: The project site is located within a seismically
active area in which more than 100 earthquakes have been recorded over
several decades. Of these, two were large events which resulted in
significant damage to structures. In 1949, an earthquake centered in the
Olympia area about 50 miles from Longacres registered a Richter magnitude
of 7.1. In 1965, a Richter magnitude of 6.5 earthquake was centered between
Seattle and Tacoma only a few miles from Longacres. On the basis of past
earthquake activity, the Puget Sound region is assigned a Zone 3 rating for
seismic activity on a scale of 1 (lowest) to 4 (highest) in the Uniform
Building Code (UBC) (1988 Edition) . For Seismic Zone 3, a seismic zone
factor of 0.30 is applicable based on the UBC Table 23-I. Based on the
results of our explorations, it is our opinion that the soil profile may be
characterized using site coefficient S3, based on UBC Table 23-J. Site
coefficient S3 results in a site factor equal to 1.5.
Evaluation of the potential for damage from an earthquake at a site can
be accomplished either through the procedure presented in the UBC or by
evaluating a site's specific seismic Response Spectra for different
probabilities of exceedence. This analysis is not presented in this report
but will be presented in a subsequent report addendum.
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Liquefaction Potential: Liquefaction refers to a condition where
vibration or shaking of the ground, usually from earthquake forces, results
in development of high pore pressures and subsequent loss of strength, or
liquefaction, in a zone of soil. In general, soils which are susceptible
to liquefaction include loose to medium dense clean to silty sands which are
below the water table.
Evaluation of the liquefaction potential is complex and depends on
several parameters including soil grain size, grain shape, soil density,
surface geometry, soil layer geometry, static stresses, as well as the
design ground acceleration. Using an empirical approach to evaluate the
potential for liquefaction, our analysis indicates that most of the site is
underlain by 10 to 15 feet of loose sand which has a moderate to high risk
of liquefying under a Magnitude 7.5 design earthquake with a horizontal
ground acceleration of 0.15 g. In the vicinity of Borings 2, 4, 5, 6, 8,
9, 12, 16, 17 and 18, we observed 10 to 30 feet of sand which is susceptible
to liquefaction. With the exception of Borings 16, 17 and 18, the zones of
sand susceptible to liquefaction are above a depth of about 35 feet. Boring
16 encountered a 10-foot zone from about 40 to 50 feet, Boring 17
encountered scattered layers of sand susceptible to liquefaction down to a
depth of 55 feet and Boring 18 encountered a loose zone from 70 to 80 feet.
The effects of liquefaction are twofold: first, liquefaction usually
results in loss of bearing capacity and resulting settlement. Second,
liquefaction may result in reduction of lateral support for structures
supported on piles. The loss of bearing capacity and settlement may result
in cracking of on-grade floor slabs and/or loss of support for shallow
foundations (i.e. , footings) . The reduction in lateral support of piles is
not considered to be as significant due to the integrity of the near-surface
soils above the ground water table that will tend to act as a diaphragm.
The risk of damage due to liquefaction can be minimized by ground
improvement techniques, or by designing the structure to withstand a certain
amount of loss of foundation support. Ground improvement techniques include
dynamic compaction in which a large weight is dropped on the ground,
vibroflotation in which sand is introduced into the ground while vibrating
the surrounding soil with steel pipe probe, use of driven displacement piles
and stone columns, which are similar to vibroflotation but using gravel
instead of sand. We are not recommending specific liquefaction mitigation
measures in this report. However, in evaluating the impact of possible
9
damage due to liquefaction and the economics of minimizing this risk in
specialized locations, the risk to other buildings and facilities in the
vicinity experiencing damage due to liquefaction during an earthquake should
also be considered.
SITE PREPARATION AND EARTHWORK
Site Preparation: We recommend that all existing vegetation, major
tree root systems, asphalt concrete pavement, concrete slabs and footings,
crushed rock and other obstructions be removed from building and pavement
areas. Any foundations or other embedded elements should be removed if they
will interfere with pile or new utility installations. We recommend
obstructions be removed to a minimum depth of 3 feet below planned finish
floor or pavement grades. Base course crushed rock removed during site
preparation activities can be stockpiled for possible reuse provided the
rock does not become contaminated with soil. Soil-contaminated crushed rock
may be used for fill where compaction and free drainage are not critical.
For existing undeveloped areas, we recommend that all brush and other
debris be removed. Tree roots larger than 2 inches in diameter should be
grubbed from building sites. Where less than 2 feet of new structural fill
is anticipated, we recommend that any grass and sod mat be stripped from
settlement-sensitive areas (e.g. , building and pavement areas) . Where site
grades will be raised by more than 2 feet with structural fill, we recommend
that the grass and lowlying vegetation be trimmed close to the ground
surface and the cuttings wasted off-site prior to placing fill.
We anticipate that most of the soils exposed during site preparation
work will vary from native loose sand and soft to medium stiff silt to fill
varying from soft silt to compacted sand and gravel. Existing fill which
contains organic matter such as straw or wood was encountered across
portions of the site. In general, such fill may be present at scattered
locations east and south of the main race track. Organic material would
result in long term settlement as the material gradually decomposes. Thus,
prior to or during site preparation activities, we recommend that four to
six shallow test pits be accomplished in each building area to determine if
any fill with organic matter is present. We recommend that fill with
organic material be removed from building areas and replaced with structural
fill. We recommend that any manure or soil mixed with manure be removed
underneath sealed areas (e.g. , pavement or slab areas) .
10
4
Where the new building or pavement grades will be less than 3 feet
above existing grades, we recommend that the exposed subgrades in pavement
and on-grade slab areas be evaluated by thorough proofrolling with heavy
rubber-tired construction equipment (dry weather construction) or by probing
(wet weather construction) . During dry weather, we recommend that all
loose, soft, or otherwise unsuitable areas be compacted with a heavy roller
such that the surface is firm and unyielding. If the subgrade cannot be
adequately compacted or if the work is performed during wet weather, all
soft or loose zones should be removed and replaced with structural fill to
the depth determined by the geotechnical engineer. Geotextile fabric may
be necessary to aid in stabilizing some areas. The need, specifications and
use of fabric should also be determined by a representative of GeoEngineers.
The existing fill and native soils at the site are moisture sensitive
and will become soft when wet and disturbed. We recommend that site
preparation and earthwork be performed during the normally drier late spring
through early fall months when the surficial soils will provide better
support for construction equipment.
If site preparation is accomplished during wet weather, no attempt
should be made to compact or proofroll the surface. These activities would
cause softening and rutting which could require extensive repair. All
construction activities during wet weather should be done from (or on)
access roads and layout areas which are constructed using pads of quarry
spalls, gravel or clean pit run. Geotextile fabric can aid wet weather
earthwork construction significantly. We should be consulted for applica-
bility and specifications.
Structural Fill: All new fill in building, pavement or other
settlement-sensitive areas should be placed as compacted structural fill
after the site has been prepared as described above. All structural fill
material should be free of debris, organic contaminants and rock fragments
larger than 6 inches. The suitability of material for use as structural
fill will depend on the gradation and moisture content of the soil. As the
amount of fines (material passing a No. 200 sieve) increases, soil becomes
increasingly more sensitive to small changes in moisture content and
adequate compaction becomes more difficult to achieve. We recommend that
structural fill contain no more than about S percent fines in the portion
passing a 3/4-inch sieve for placement in wet weather or on a wet subgrade.
11
The percent fines can be higher for placement in dry weather, providing that
the fill material is moisture conditioned as necessary for proper compac-
tion.
The near-surface soils at the site consist of sand, silty sand, silt
and sandy silt. Excavated silt typically will not be suitable for use as
structural fill, but may be used in nonstructural applications such as
landscape areas or as preload fill, subject to the limitations discussed in
Preload/Surcharge Fill. Excavated sand may be suitable for use as
structural fill, depending on the fines content of the soils, the moisture
content of the soil when excavated and the prevailing weather conditions at
the time of placement. If these soils become too wet, they will become
difficult to place and compact to earthwork specifications. In general, we
anticipate that a majority of excavated material will typically not be
suitable for use as structural fill because of its fines or moisture
content. We suggest that the project plans and budget assume that excavated
soil will either be 'placed in landscaping areas or removed from the site.
Use of excavated soils for backfill of utility trenches or other
excavations as subject to the conditions and restrictions described below.
Pipe bedding where required must be imported.
Structural fill placed in building areas and within 2 feet of the
finished subgrade surface in sidewalk and pavement areas should be compacted
to at least 95 percent of the maximum dry density determined in accordance
with ASTM D-1557. At a depth of more than 2 feet below subgrade elevation
in sidewalk and pavement areas, the structural fill should be compacted to
at least 90 percent of the same standard. We recommend that structural fill
be placed in loose layers not more than 8 inches thick. Each lift must be
conditioned to the proper moisture content for compaction and uniformly
compacted to the specified degree before placing subsequent layers.
In areas where the subgrade is particularly soft, it might be desirable
to place a geotextile fabric between the new fill and the on-site soils to
separate these materials. We recommend that a nonwoven fabric such as
Mirafi 140N or Phillips Fabrics 4NP be used for this purpose.
We recommend that temporary fill slopes be inclined no steeper than
1H:1V. Permanent fill slopes should be constructed no steeper than 2H:1V.
We suggest that permanent fill slopes be inclined at 3H:1V or flatter for
ease of landscape maintenance or mowing.
12
We recommend that a representative from GeoEngineers, Inc. be present
during site preparation and structural fill placement. Our representative
would observe the work, evaluate subgrade performance under proof-
rolling/probing, perform representative in-place density tests to determine
if the required compaction is being achieved and advise on any modifications
to procedures which may be appropriate for the prevailing conditions.
Erosion Control: Control of off-site transport of sediment will be an
important environmental protective constraint. In our opinion, conventional
erosion/sedimentation practices will be appropriate. We strongly recommend
that erosion control measures be installed prior to site grading activities.
The goal of erosion/sedimentation control system design must be to (1)
prevent mobilization of sediment, and (2) efficient trap sediment in surface
runoff before it can be transported off site or to on-site critical areas
such as the wetlands. We recommend that the project grading plans be
prepared by someone properly qualified for, and attentive to, the erosion/
sedimentation issue. We will be pleased to work with the designer in that
regard.
The existing native and fill soils will be very difficult to filter or
precipitate once suspended in surface runoff. Therefore, it will be
important to cover and avoid vehicle traffic on exposed soil, especially
during wet weather. Coarse sand, straw mulch, hog fuel, nonwoven geotextile
or visqueen sheets can be used for cover, depending on the specific
conditions. The runoff must be routed through some combination of filters
and sedimentation ponds to clarify the water. Water treatment with a
flocculant can also be effective.
Dust control will be necessary during dry weather. Proper traffic
surfaces such as asphalt treated base (ATB) will help significantly. Water
on unpaved surfaces will be adequate.
Fill Settlement: We anticipate that the building areas will receive 2
to 4 feet of fill in order to achieve the desired floor grades. Most of the
site is underlain by 5 to 10 feet of compressible silt. However, as
discussed under SUBSURFACE CONDITIONS, portions of the site are underlain
by 15 to 25 feet of silt. We estimate that settlements resulting from
placing 2 feet of fill will be on the order of 1 to 1i inches of settlement
across most of the site, and up to 2;1 inches of settlement where thicker
deposits of silt are present. Four feet of fill would result in between 1�1
and 4# inches of settlement. Actual settlements will vary for each building
13
site depending on the height of the fill and variations in the thickness and
compressibility of the silt underlying the site. The estimated settlements
resulting from a range of fill, slab and/or floor loads are presented in
Figure 5.
Placement of fill or other loads will also induce settlements within a
certain distance of the load in proportion to the loaded area. We estimate
that settlements induced by large area loads such as a building pad will be
minor at a distance of 25 feet and negligible at a distance of 50 feet from
the edge of the loaded area.
Based on the laboratory test results and on our past experience with
projects in the site vicinity, we estimate that across most of the site
approximately 90 percent of the anticipated settlement will occur in about
three to five weeks. However, thicker deposits of silt were encountered in
the vicinity of Borings 10, 13, 15 and 16. Where the deposits of silt are
15 to 30 feet in thickness, the settlements could require up to three to
five months. As discussed in a subsequent section of this report, the time
required for settlements to occur could be reduced by placing a surcharge
fill.
Fill-induced settlements could affect the performance of settlement
sensitive facilities which are supported on-grade such as floor slabs,
pavements, utilities, sidewalks, patios and entryways. Therefore,
settlement performance and construction timing should be carefully
considered in design. Of particular concern is the differential settlements
which could occur between the pile-supported buildings and surrounding
facilities supported on grade. Options for support of the lower floor slabs
for the buildings are discussed in detail in a subsequent section of this
report. To minimize impacts on other settlement-sensitive facilities (e.g. ,
pavements, utilities, sidewalks, patios and entryways) , we recommend that
the site fill be placed at least six weeks prior to the construction of
these facilities. For any buildings situated in the vicinity of Borings 10,
13, 15 and 16, we should be consulted as to time anticipated for fill-
induced settlements to occur.
Inconsistent subsurface conditions were encountered in Boring 18. As
described in SUBSURFACE CONDITIONS, compressible clay with layers of loose
sand was encountered from a depth of 46 to 70 feet. We estimate that
surface loads of 200 and 600 psf would settle an additional 1/2 and 1 inch,
respectively, due to the effects of this deposit. These settlements could
14
require up to seven months to occur. As this deposit was not encountered
in nearby borings, any settlements caused by this deeper deposit could
result in unacceptable differential settlements underneath a building.
Therefore, after specific building sites and proposed surface and building
grades have been finalized, we recommend that additional borings and/or
Dutch cone tests be accomplished in the vicinity of Boring 18 to better
define the limits of this deeper deposit, and to further evaluate potential
settlements and time for settlements to occur in this area.
EXCAVATIONS
At this time, we understand that none of the buildings will contain
basements. Therefore, we expect that the majority of excavations will be
relatively shallow, on the order of 5 to 10 feet for pile caps and
utilities. However, elevator and/or special foundations which require
deeper excavations may be required for some or all of the buildings; deep
excavation may also be required for some utility components such as pump
stations.
In general, we anticipate that the ground water level across the site
will be at a depth of 4 to 6 feet during the winter, spring, and early
summer months, and at a depth of about 10 to 12 feet during the late summer
and fall months. Thus, the amount of water encountered in an excavation
will depend in part on the depth of the excavation and on the time of year
it is accomplished. We anticipate that dewatering of excavations which
extend no deeper than 2 to 4 feet below the static ground water level can
be accomplished using shallow sumps and small pumps. Deeper excavations
might require more extensive dewatering methods, depending on the depth and
size of the excavation. Two possible dewatering alternatives for the site
include a well point system consisting of closely spaced small-diameter
pipes, or a deep well system using pumps set in larger diameter wells. The
number and depth of well points or wells will depend on the depth and size
of excavation, and on the soil conditions in the vicinity of the excavation.
Excavations above the ground water table can be made with temporary
side slopes of about 1H:1V. Temporary slopes may need to be flattened where
localized zones of extremely loose or soft soils are encountered.
Excavations extending below the ground water table should be sloped no
steeper than 3H:1V or flatter as necessary to minimize sloughing or
ravelling of the cut faces. We do not anticipate any significant permanent
cut slopes on the site.
15
Temporary retention systems must be anticipated where deep excavations
are required. In our opinion, conventional temporary shoring measures such
as a moveable trench box or sheet piles will be appropriate. If temporary
shoring is required, we should be consulted to provide parameters for design
of the shoring system.
FOUNDATION SUPPORT
General: We recommend that the buildings be pile-supported due to the
presence of surficial loose and soft deposits across the site.
For small or lightly loaded structures which are not settlement-
sensitive, conventional shallow spread footings may be appropriate. For
existing site soils, an allowable soil bearing pressure of 1,000 pounds per
square foot may be used for design. We recommend that all footings be
supported a minimal 18 inches below the final lowest adjacent grade and have
a minimum width of 16 inches. We recommend that a representative from our
firm examine all footing excavations prior to forming or pouring concrete.
We recommend that we review proposed structures supported on shallow
foundations to evaluate potential settlement impacts.
Based on the intended heights of the proposed buildings, we anticipate
that piles which have design capacities in the range of 40 to 100 tons per
pile will be suitable for this project. We understand that the Boeing
Company currently plans on using augercast piles for support of the
buildings. However, driven piles could also be used. We have included
design values for different types of driven piles.
Some communities in the Seattle area have placed a maximum length-to-
diameter ratio of 30:1 on augercast piles based on their interpretation of
Section 29 of the Uniform Building Code. It is our opinion that this
portion of Section 29 does not apply to augercast piles, as the piles are
not constructed as uncased concrete piles (for which the restriction was
written) . In our opinion, the soil conditions at the project site are
suitable for installing augercast piles to the depths recommended below.
We understand that the City of Renton will usually waive this restriction
if the owner provides appropriate supporting documentation. We recommend
that the Boeing Company discuss this requirement with City of Renton
officials prior to finalizing design plans.
Axial Pile Capacity: We recommend that the buildings be supported on
piles which extend into the underlying medium dense to dense sand. The
16
depth at which this stratum occurs varies from about 15 to 35 feet across
the site. We should be consulted to evaluate required pile penetrations
once specific building locations are finalized. A tabulation of recommended
penetration into the supporting sand stratum and allowable axial capacities
for the various pile types considered is presented below. This information
is intended to be used as a guide for design purposes.
Table 1 - Axial Pile Capacity
Penetration into
Medium Dense to
Dense Sand *Allowable Pile Capacity (tons)
Pile Type and Size (feet) Downward** Uplift
9-inch tip timber 20 30 15
30 40 20
12-inch steel pipe 20 32 16
30 45 22
40 55 28
12-inch square precast 20 47 22
30 70 30
40 90 40
12-inch augercast 20 30 15
30 40 20
40 50 25
16-inch augercast 20 40 20
30 60 40
40 85 40
18-inch augercast 20 50 25
30 70 35
40 100 50
*Values are for the total of dead and long-term live loads. For piles which
extend into the sand 30 or 40 feet, the values may be increased by one-third
when considering live loads of short duration such as wind or seismic
forces. For piles which extend only 20 feet into the sand, we recommend no
increase for short-term loads since the potential loss of capacity due to
liquefaction potential around the upper portion of a pile would largely
offset the increase in capacity around the lower part.
**For piles installed in the vicinity of Boring 18, the penetrations to
achieve desired capacities may be greater due to deeper deposits of
compressible soils. As discussed under Fill Settlements, we recommend we
be retained to reevaluate pile penetration/capacity relationships in the
vicinity of Boring 18 once specific building sites have been finalized.
17
The allowable capacities presented above are based on the strength of
the supporting soils for the penetrations indicated and include a factor of
safety of about 2.5. The capacities apply to single piles. If piles within
groups are spaced at least three pile diameters on center, no reduction for
pile group action need be made.
The structural characteristics of pile materials and structural
connections might impose limitations on pile capacities and should be
evaluated by your structural engineer. For example, steel reinforcing will
be needed for augercast piles subjected to uplift. We recommend that a
single reinforcing bar be installed the entire length of the augercast pile
to develop the allowable uplift capacities presented in Table 1. There is
some risk associated with supporting structural elements on single piles.
Therefore, we recommend that all major structural elements be supported on
pile groups consisting of two or more piles.
Pile Downdrag: Pile downdrag forces develop when surrounding
compressible soils settle relative to a pile, thus interacting with and
adding load to the pile. We anticipate that most of the site will receive
2 to 4 feet of fill. As discussed above, we anticipate that the fill across
most of the site will require three to five weeks to settle. However, time
for settlement could take up to five months across portions of the site
which are underlain by thicker deposits of silt.
Downdrag forces on the piles will also vary across the site with
varying thicknesses of silt. We estimate that downdrag forces ranging up
to as much as 25 tons could develop depending on the pile type and the
thickness of compressible soils. If the building fill, slab preload fill,
and any new fill placed within 40 feet of the structure are placed
sufficiently far in advance of pile installation, pile downdrag forces need
not be considered in design. We recommend that we be retained to evaluate
the time for fill settlements to occur and anticipated downdrag loads for
individual buildings after each building location, construction schedule and
grade are finalized.
Lateral Pile Capacity: The allowable lateral loads for the various
pile types considered are presented in Table 2. These lateral capacities
are based on a center-to-center pile spacing of at least three pile
diameters, adequate steel reinforcement, and pile-head fixity against
rotation. The capacities are based on a maximum pile deflection of
approximately 1/2 inch.
18
Table 2 - Lateral Pile Capacity
Pile Type and Tip Diameter Allowable Lateral Loads (tons)
9-inch tip timber 2.0
12-inch steel pipe 4.0
12-inch square precast 3.7
12-inch augercast 2.7
16-inch augercast 4.2
18-inch augercast 5.0
We recommend that reinforcing be installed to a minimum depth of 15, 19
and 22 feet in 12- , 16- and 18-inch-diameter augercast piles, respectively,
to resist bending movements associated with lateral loading.
Resistance to lateral loads can also be developed by passive pressure
on the faces of pile caps, grade beams, tie-beams and other buried
foundation elements. Allowable passive resistance values are presented
below under LATERAL RESISTANCE. Sliding friction on the base of pile
supported foundation elements should be ignored.
Pile Settlement: We estimate that the settlement of pile foundations,
designed and installed as recommended, will be on the order of 1/2 to
3/4 inch or less. Most of this settlement will occur rapidly as loads are
applied. Postconstruction differential settlements should be minor.
Pile Installation: Augercast (cast-in-place) concrete piles should be
installed to the recommended penetrations using a continuous-flight, hollow-
stem auger. As is common practice, the pile grout is pumped under pressure
through the hollow stem as the auger is withdrawn. Reinforcing steel for
bending and uplift is placed in the fresh grout column immediately after
withdrawal of the auger.
We recommend that the augercast piles be installed by a contractor
experienced in their placement and using suitable equipment. Grout pumps
should be fitted with a volume-measuring device and pressure gauge so that
the volume of grout placed in each pile and the pressure head can be easily
determined. While grouting, the rate of auger withdrawal should be
controlled such that the volume of grout pumped is equivalent to at least
115 percent of the theoretical hole volume. A minimum grout line pressure
of 100 psi should be maintained while grouting. We recommend that a minimum
3500 psi grout strength be used for augercast piles. We recommend that
there be a waiting period of at least eight hours between installation of
piles spaced closer than 10 feet center-to-center, in order to avoid
19
disturbance of concrete undergoing curing in a previously cast pile. We
also recommend that the contract documents for augercast piling installation
include a provision for drilling three to four pile holes per building and
withdrawing the auger without turning prior to grouting so that our
representative can examine the soil column in the auger flights and compare
actual subsurface stratigraphy with that expected from our borings.
It should be noted that the recommended pile penetrations and allowable
capacities presented above are based on assumed uniformity of soil
conditions between the explorations. There may be unexpected variations in
the depth to and characteristics of the supporting soils across the site.
In addition, no direct information regarding the capacity of augercast piles
(e.g. , driving resistance data) is obtained while this type of pile is being
installed. Therefore, it is particularly important that the installation
of augercast piles be carefully monitored by a qualified individual working
under the direct supervision of a properly experienced registered engineer.
Accordingly, we recommend that pile installation be monitored by a member
of our staff who will observe installation procedures and evaluate the
adequacy of individual pile installations.
If driven piles are selected, it is important that the piles be driven
with a hammer having an adequate energy. The minimum hammer energy as well
as other details of pile driving including refusal criteria can be provided
once a pile type and size have been selected. If driven piles are selected,
we recommend that pile installation be monitored by a member of our staff
who would observe installation procedures and evaluate the adequacy of
individual pile penetrations.
Pile Testing Program: Due to the widely spaced nature of the borings
and the variability in thickness of loose sand and soft silt across the
site, we recommend that a pile load test program be included prior to
installation of production piles. If augercast piles are used for support,
we recommend one pile load test per building be accomplished. Each pile
load test should be performed in accordance with ASTM D 1143 and loaded in
accordance with Section 5.1 (Standard Loading Procedure) .
If driven piles are selected, we recommend that at least four piles be
test driven at each building to better determine order lengths. Depending
on the type of driven pile selected, it may be appropriate to use a pile
driving analyzer during the test driving program.
20
FLOOR SLAB SUPPORT
As described previously, the site is underlain by variable deposits of
compressible silt and the potential for slab settlement must be considered
in design. In our opinion, there are three options for slab support,
depending on the final grades selected and time constraints during
construction. These options are to (1) support the slab on-grade where the
entire slab is at or below the existing ground surface, (2) support the slab
on a pad of structural fill above the existing grade after allowing
sufficient time for the fill to settle, and (3) structurally support the
slab on piles. As noted previously, we expect that Option 1 is not widely
applicable due to requirements from flood protection. Exceptions might
include below-grade utility vaults or loading dock ramps. Within enclosed
below-grade areas (e.g. , vaults) buoyancy must be considered in the design.
We recommend that any slab supported on grade (Options 1 or 2) be
supported on at least 18 inches of structural fill in order to provide
reasonable uniform slab support. The structural fill should meet the
requirements described in the SITE PREPARATION AND EARTHWORK section of this
report. The pad of structural fill *nay be developed by either excavating
and replacing the upper on-site soils (for Option 1) , or by building a
structural fill pad on top of the existing surface (Option 2) . We recommend
that the top 6 inches of the 18-inch pad consist of free-draining sand and
gravel or crushed rock containing less than 5 percent fines. A vapor
barrier should be placed between the base course and the floor slab to
inhibit condensation on the underside of the slab.
Option 1 might be feasible for buildings where the lowest floor slab
can be placed no higher than 6 inches above existing grade across the entire
building area. As discussed above, some overexcavation would be required
to construct the structural fill pad under the slab. For Option 1, we
estimate that settlement of sustained floor loads of up to 150 pounds per
square foot will be in the range of 1/2 to 3/4 inch.
We anticipate that Option 1 may not be feasible across most of the site
if finished grades will be above the present ground surface. Option 2 would
involve supporting the floor slab on a pad of structural fill above existing
grades. We estimate that a surface load of 200 psf could result in 1 to 1�1
inches of settlement. Thus, for Option 2 we recommend that slab areas be
preloaded to minimize post-construction settlement of the slab. Slabs
supported on structural fill which extends above existing grades should not
21
be formed and poured until all settlement due to the fill and preload is
complete. Required time for settlements to occur is discussed in the Fill
Settlement section of this report. We recommend a monitoring program using
settlement plates to confirm that all settlements are effectively complete
before construction of slabs. The monitoring plates should be installed and
read as recommended under PRELOAD/SURCHARGE FILL. We estimate that the
postconstruction settlement of slabs constructed after allowing settlement
of the fill and preload to occur will be minor.
Option 3 would consist of structurally supporting the slab (i.e. ,
supporting the slab on piles) . We recommend that a vapor barrier be placed
beneath the slab. Postconstruction, settlement of structurally supported
slabs should be minor.
For slabs supported on at least 18 inches of structural fill, a
vertical subgrade modulus of 115 pci (pounds per cubic inch) may be used for
slab design. This vertical subgrade modulus is for a 1-foot by 1-foot
loaded area.
Earthquake shaking may result in cracking of the slab due to liquefac-
tion and any resulting subsidence and nonuniform settlement between the slab
and pile-supported structure. This potential damage to the slabs can be
eliminated or minimized if the slabs are pile-supported, or if ground
improvement measures are accomplished. However, unless the slab will be
supporting expensive and highly sensitive equipment, we believe it would be
more practical as well as more economical to repair the slab in the future
if it is damaged due to earthquake shaking.
PRELOAD/SURCHARGE FILL
The purpose of a preload program is to preinduce a major portion of the
settlements which would otherwise occur when fill and building floor loads
are applied. We recommend that preload fill be placed in the building areas
to minimize differential settlements between the pile-supported building and
the on-grade slab. A preload program will also significantly reduce
potential differential settlement due to variability in areal loading and
thicknesses of compressible soils. The time required for settlements due
to fill or slab loads to occur can be accelerated by placing additional fill
as a surcharge. The height of surcharge required will depend on the
thickness of underlying silt and the time allowable for settlements to
occur. Other options such as installing wick drains could also be used to
22
accelerate settlements. If surcharge fills or other measures are desired
to accelerate settlements, we should be retained to provide recommendations
as appropriate.
We recommend that preload/surcharge fill consist of well-graded, free-
draining sand or sand and gravel, as described above for structural fill,
so that the preload fill can subsequently be used in grading other portions
of the site. Use of clean sand and gravel will also minimize difficulties
in rehandling and compaction if the fill must be removed during inclement
weather.
Excavated soils which are not suitable for use as structural fill may
be used for preload fill, however, placement and removal will be severely
limited by inclement weather. In addition, use of this material will
require about 25 percent more preload height due to its lower density. Use
of native soil surcharge material will almost certainly contaminate the
upper surface of building pad fill. This problem can be compensated for by
increasing the height of the building pad fill.
The crest of the preload/surcharge fill should extend to full height at
least 10 feet outside of planned building lines. If any buildings have the
potential to be expanded at a future time, the full height of the preload
should extend at least 25 feet beyond those building walls which abut the
future expansion area. Side slopes of preload fill should be 1;i:1
(horizontal to vertical) or flatter. Preload fill need be compacted only
to the extent necessary to support construction equipment. The preload
surface should be crowned slightly to prevent ponding of water.
We recommend that the preload, if used, remain in place for a minimum
of five weeks, or until settlement marker observations indicate that
consolidation of the underlying compressible strata is largely complete.
The actual preload period required will depend on the thickness and extent
of compressible soil layers. Following the preloading period, the excess
fill can be removed from the building areas and used as structural fill in
parking areas, assuming the preload fill is of the proper gradation.
We recommend that a series of monitoring plates be installed prior to
placing any fill in building areas to evaluate the rate of building pad and
preload fill settlement and to establish when the preload can be removed.
An example of a suitable monitoring plate and a description of monitoring
procedures is presented in Figure 6. Initial elevation readings of the
settlement plates must be obtained when they are set in place and before any
23
fill is placed if subsequent readings are to be meaningful. Elevations of
the plates and the average adjacent ground surface should then be determined
on a twice-weekly basis during fill placement and weekly thereafter so that
settlement progress can be defined. Review of the survey data provides
important information regarding the site performance and construction
schedule.
The varied soil profile defined by our explorations indicates that
there will be differences in settlement magnitude and rate across the site.
Consequently, we recommend that settlement monitor plates be installed at
about 100 to 150 feet spacing within each building.
The presence of the measurement rods which extend above the settlement
plates and through the fill will inhibit the mobility of earthmoving
equipment to some extent and the contractor must exercise care to avoid
damaging or displacing the rods. The construction documents should
emphasize the importance of protecting settlement plates and measuring rods
from disturbance.
The preload fill should be left in place until the rate of settlement
has stopped or is occurring at a uniform slow rate. If a surcharge fill is
placed, it should not be removed until the magnitude of estimated settlement
under design load conditions has been achieved or exceeded.
For fills which cover a relatively large area and which are not
surcharged, the fill should be in place as long as possible before paving
and some fine grading should be anticipated to restore the desired finished
grade.
SUBGRADE WALLS
The lateral soil pressures acting on subgrade walls will depend on the
nature, density and configuration of the soil behind the wall and the amount
of lateral wall movement which can occur as backfill is placed. For walls
that are free to yield at the top at least one-thousandth of the height of
the wall, soil pressures will be less than if movement is limited by such
factors as wall stiffness or bracing. Assuming that the walls are
backfilled and drained as outlined in the following paragraphs, we recommend
that yielding walls supporting horizontal backfill be designed using an
equivalent fluid density of 35 pcf (pounds per cubic foot) (triangular
distribution) while nonyielding walls be designed using an equivalent fluid
density of 55 pcf. The above-recommended lateral soil pressures do not
24
include the effects of surcharges such as floor loads, traffic loads or
other surface loading. Surcharge effects should be considered as appropri-
ate.
In settlement-sensitive areas (e.g. , beneath on-grade slabs) , backfill
for subgrade walls should be compacted to at least 95 percent of the maximum
dry density determined in accordance with ASTM D-1557. At other locations,
wall backfill should be compacted to between 90 and 92 percent of ASTM
D-1557. Measures should be taken to prevent the buildup of excess lateral
soil pressures due to overcompaction of the backfill behind the wall.
Positive drainage should be provided behind subgrade walls by placing
a zone of free-draining sand and gravel containing less than 5 percent fines
(material passing No. 200 sieve) against the wall. The drainage zone should
be at least 18 inches thick (measured horizontally) and extend from the base
of the wall to within 1 foot of the finished ground surface behind the wall.
Perforated drainpipe having a minimum diameter of 4 inches should be
embedded within the free-draining material at the base of the wall along its
entire length. This drainpipe should discharge into a tightline leading to
an appropriate collection and disposal system. Alternatively, weep holes
made at about 4-foot centers at the base of the walls should be sufficient
to drain water from exterior walls such as those adjacent to loading dock
areas.
LATERAL RESISTANCE
Resistance to lateral foundation loads developed on the soil-foundation
element interfaces is a function of the frictional resistance which can
develop on the base and the passive resistance which can develop on the face
as the below-grade elements of the structure tend to move into the soil.
For on-grade floor slabs founded on structural fill placed and compacted in
accordance with our recommendations, the allowable frictional resistance may
be computed using a coefficient of friction of 0.5 applied to dead-load
forces. Frictional resistance should be ignored for pile supported
foundation elements. The allowable passive resistance on the face of
footings, grade beams or other embedded foundation elements can be computed
using an equivalent fluid density of 250 pcf (triangular distribution) where
these elements are cast directly against undisturbed native soils.
Alternatively, passive pressures may be computed using an equivalent fluid
density of 450 pcf if all soil extending out from the face of the foundation
25
element for a distance at least equal to two and one-half times the height
of the element consists of structural fill compacted to at least 95 percent
of ASTM D-1557.
The allowable passive pressures will be less for any elements of the
structure which extend below the water table. Below the water table, the
allowable passive resistance for native soil and structural fill should be
reduced to 120 and 200 pcf, respectively. We recommend that buoyant passive
pressures be assumed for those portions of embedded elements which extend
more than 5 feet below the existing surface.
Where floor slabs abut retaining walls, available passive resistance
should be calculated from the bottom of the slab. The above values do not
include a factor of safety. An appropriate factor should be included. For
live loads, it is our opinion that no safety factor is needed. For dead
loads, a safety factor in the range of 1.4 to 1.5 is suggested.
PAVEMENTS
Pavement subgrade areas should be stripped and proofrolled or otherwise
examined as recommended in SITE PREPARATION AND EARTHWORK. We recommend
that all paving areas be underlain by a minimum of 12 inches of structural
fill. Across most areas of the site, this will require placement of new
fill, either by raising site grades or by excavation and replacement of
native soils with structural fill. Some portions of the site may be
underlain by existing sand and gravel fill for which the upper 12 inches
should be recompacted to meet the criteria for structural fill. Where the
exposed subgrade is' soft, these soils must be excavated and replaced with
structural fill to form a firm, unyielding subgrade. Assuming that proper
subgrade preparation is accomplished and that pavement construction is done
during a period of extended dry weather, we recommend that the pavement
section in automobile parking areas consist of at least 2 inches of Class B
asphalt concrete, 4 inches of clean crushed rock with less than 5 percent
passing the No. 200 sieve, and a subbase consisting of at least 12 inches
of compacted clean sand and gravel fill. In roadway and loaded truck areas,
the thicknesses of asphalt concrete, crushed rock and subbase should be
increased to 3, 6 and 15 inches, respectively. The Class B asphalt concrete
and crushed rock should meet the criteria specified in Section 5-04 and
9-03.9(3) , respectively, of the Washington State Department of Transporta-
tion Standard Specifications.
26
Alternatively, a California Bearing Ratio (CBR) of 15 may be used for
design to describe the pavement support conditions at the surface, presuming
that the 12 inch subbase of sand and gravel is placed as recommended. If
pavement sections other than those presented above are used, we recommend
that all pavement sections include at least 4 inches of free-draining
crushed rock with less than 5 percent fines.
If pavements are constructed during wet weather or if the subgrade is
wet and cannot be compacted satisfactorily, it will be necessary to place
at least 6 to 12 inches of additional free-draining sand and gravel to
provide adequate pavement support. The actual thickness of additional sand
and gravel fill required will depend upon the firmness of the subgrade at
specific locations and should be evaluated during construction. In soft
subgrade areas, we recommend that consideration be given to placing a woven
geotextile between the native soils and the granular fill to separate these
materials and strengthen the pavement section.
The crushed rock base course and the granular fill subbase should each
be compacted to at least 95 percent of the maximum dry density determined
in accordance with ASTM D-1557. It is very important to pavement perfor-
mance that backfill in utility trenches underlying paved areas also be
compacted in accordance with the recommendations for structural fill
presented in this report.
As discussed in this report, fill placed to raise site grades will be
subject to settlements due to consolidation of underlying silt deposits.
We estimate that across most of the site settlements will occur within six
weeks of fill placement. Construction of on-grade utilities, pavements,
slabs, curbs, and other settlement-sensitive facilities should be delayed
until settlements due to filling are complete.
PERMANENT DRAINAGE CONSIDERATIONS
For permanent erosion protection, all cut and fill slopes should be
seeded or planted. The slopes may need a temporary erosion covering such
as jute matting or other erosion protection matting until the vegetation is
well established.
We recommend that the pavement surfaces be sloped so that surface
drainage flows away from buildings. We recommend that all roof drains be
collected in tightlines for diversion into the storm drain system. Curbs,
berms or drainage ditches should be constructed along the top of fill slopes
27
to intercept surface runoff and prevent this water from flowing down the
slopes. Collected water should be routed to an appropriate disposal point.
OTHER CONSIDERATIONS
Design frost depths in the Puget Sound area are typically taken as
18 inches below the ground surface. We believe that 18 inches is an
adequate design frost depth for the project site.
We recommend that foundations supporting sensitive equipment be pile
supported. In general, it is our opinion that the site soil conditions are
such that vibrations will be attenuated through the ground with distance.
We expect that one of the largest sources of vibration will be traffic on
the railroad lines situated along the west edge of the site. Due to the
location of the railroad tracks and the presence of deeper soft and loose
deposits in the southern end of the site, we suggest that buildings which
will house equipment sensitive to vibration be situated in the east half of
the site north of the existing Sales Pavilion. It will be possible, in our
opinion, to design vibration-isolated foundations if needed at other
locations. If desired, we can provide specific vibration studies once
specific building locations and vibration tolerance criteria have been
finalized.
The pH and corrosivity potential across the project site was evaluated
by testing 10 samples. The test results are presented in Appendix B. In
summary, most of the soils tested were mildly corrosive. All of the samples
tested in the acidic range. The redox (oxidation-reduction potential)
testing indicates that the soil conditions are favorable for supporting
sulfate reducing bacteria. We recommend that corrosion protection measures
such as coating or wrapping pipes in conjunction with backfilling with free-
draining sand or pea gravel be considered in the final design for utilities
or other buried facilities which will be susceptible to corrosion.
Some portions of the site, especially east of the main track and south
of Southwest 27th Street, may contain fill consisting of waste straw and
manure. Any organic material encountered in utility excavations should not
be reused as trench backfill. Although we have recommended that any straw
or manure encountered in proposed sealed areas (e.g. , pavement or slabs) be
removed, there might still be a potential for manure to result in the
28
presence of methane gas which could migrate to utility corridors. We
recommend the potential for methane be considered in the design and
maintenance of utilities.
LIMITATIONS
We have prepared this report for use by BE&C Engineers and their
project design team in the design and planning of a portion of this project.
The data and report should be provided to prospective contractors for
bidding or estimating purposes, but our report, conclusions and interpreta-
tions should not be construed as a warranty of the subsurface conditions.
The design details are not known at the time of preparation of this
report. As your design develops, we expect that additional consultation may
be necessary to provide for modification or adaptation of our recommenda-
tions. Some additional explorations may be appropriate once specific
building locations are selected, as discussed in this report. When the
design has been finalized, we recommend that GeoEngineers, Inc. be retained
to review the final design and specifications to see that our recommenda-
tions have been interpreted and implemented as intended.
Our scope does not include services related to construction safety
precautions and our recommendations are not intended to direct the
contractor's method, techniques, sequences or procedures, except as
specifically described in our report for consideration in design.
Variations in subsurface conditions between the explorations and also
with time should be expected. A contingency for unanticipated conditions
should be included in the budget and schedule. Construction monitoring and
testing is important to confirm that the conditions encountered are
consistent with those indicated by the explorations and to evaluate whether
or not earthwork and foundation installation activities comply with the
intent of contract plans and specifications. For consistency in the
interpretation of subsurface conditions and the application of design
recommendations, GeoEngineers, Inc. should be retained to provide construc-
tion monitoring and consultation services during earthwork and pile
foundation activities.
Within the limitations of scope, schedule and budget, our services have
been accomplished in accordance with generally accepted practices in this
area at the time the report was prepared. No other conditions, express or
implied, should be understood.
29
If there are any questions concerning this report, if more design
details are needed, or if we can provide additional services, please contact
us.
ate, Respectfully submitted,
rC'� L• T� `P' GeoEngineers, Inc.
Tochko, P.E.
Senior Engineer
C"i Jon W. Koloski
Principal
NLT:JWK:cs
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O
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0
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N
O
VICINITY MAP
Geo��Engineers FIGURE 1
G�
'r Ii
o0 . +6
Training Track `
+10 0 500 1000
p. Property Line SCALE IN FEET
a — — -- —
Oa�s / ' 3 — - - - - - - 9- - - - Sales
1NW_3 8 �
-�- Barns
-- A�► *5 11 � Pavilion+ c � A'
+mw-11 v
z - - -- -- - - - - - - - - - - - - - m
o
/ o - 4 L_
2 / o
�17 17
I \ Main Race Track
MW-4�
1 \
N� O \ O 1+ BORING LOCATION AND NUMBER
y
�— FOR CURRENT STUDY B` o 0 0 0 -�13 MW-16� -�-18 B' I MW-1
L o
� �1 � O O TMONITOR WELL LOCATION AND
d MW-1 0 O 12 NUMBER FOR CURRENT STUDY
*11AW-12 +15
O BORING OR MONITOR WELL BY
-' GEOENGINEERS FOR PREVIOUS
STUDIES FOR OTHERS
Burlington Northern RR LOCATION OF CROSS SECT ION
OPEN SWALES AND/OR MAJOR
O DRAINAGE DITCHES
O
p ai MAJOR CULVERTS
O
t
O �
r West Valle Hi hwa N ��
o do Nye
SITE PLAN
. G e o Engineers
FIGURE 2
n
A A'
rn 3p
co W W W
r rO v�
8 � 8 °° �0 . zg Z SN
ZN Z " Z N O
.) ,. '" � o g fn 8
= N M N rx m y — M8 Vm 20
20 m m
Very soft to soft silt (fill and native material) -- —
Soft to medium stiff silt (fill and native material)
0 0
_� Loose sand to silty sand
m m
y U.
u_ c
c \ Medium dense sand to silty sand
0-20 with occasional layers of -20
co
dense sand and gravel Loose sand
> m
2
W
ILU-40-
oos -40san
-60 -60
O
m
N
NOTES : 1 . SECTION LINES SHOWN ON FIGURE 2 . Horizontal Scale: 1" = 300'
Vertical Scale: 1" = 20'
2 . ELEVATIONS INTERPRETED FROM AERIAL TOPOGRAPHIC
MAP, DATED 11/ 11/78, PREPARED BY WALKER & ASSOCIATES .
3 . THE SUBSURFACE CONDITIONS SHOWN ON THE PROFILE ARE
N BASED ON INTERPRETATION BETWEEN WIDELY SPACED BORINGS
O
AND SHOULD BE CONSIDERED APPROXIMATE .
O
m
0
O
N
O \�tI CROSS SECTION A - A'
Geo��Engineers FIGURE 3
B B'
m CD3 � 0 W 00 W
3 N3pQ � p �N rO rN
� Q Q M r r 04
w
m m
Z �' to
8—
20 c oo 8 20
m Very soft silt? l(fil
Soft silt (fill?) �/? ? Loose sand to silty sand
o t It with a Very soft to soft silt with
o Loose sand to silty sand Soft silt 1 'a-tracE of peat 0
IL e sand ? _'
�i -20 Medium dense sand to silty -20
LL
C sand with occasional layers c
C of dense sand and gravel
/ a o
co �
> >
aD m
w — —40 w
40
Loose sand and medium
JL stiff silt )
a /
—60
JL
m
N
—80 —80
NOTES : 1 . SECTION LINES SHOWN ON FIGURE 2 . Horizontal Scale: 1" = 300'
J Vertical Scale: 1" = 20'
2 . ELEVATIONS INTERPRETED FROM AERIAL TOPOGRAPHIC
MAP, DATED 11/ 11/78, PREPARED BY WALKER & ASSOCIATES .
N
3 .THE SUBSURFACE CONDITIONS SHOWN ON THE PROFILE ARE
BASED ON INTERPRETATION BETWEEN WIDELY SPACED BORINGS
m AND SHOULD BE CONSIDERED APPROXIMATE .
p
p
N
\� CROSS SECTION B - B'
Geo�w Engineers
FIGURE 4
0120-090-B02 NLT : KKT 1 /3/ 91
MONSOON
SETTLEMENT ( INCHES)
CDN 00
� CD
CID
.III
m
m c
„
7, D
r m
r
r a,
0 0 0
a o CD
m
p co cn
.n
m
N o
m o 0
c
m m
v
� N
o
r
m
N
O
rJ
MEASUREMENT ROD, 1/2" PIPE
OR REBAR
CASING, 2" 0 PIPE
(SET ON PLATE, NOT FASTENED)
EXISTING COUPLING WELDED TO PLATE
GROUND SURFACE
SETTLEMENT PLATE,
16" X 16" X 1 /4"
t�
SAND PAD IF NECESSARY
(NOT TO SCALE)
I
NOTES :
1 . INSTALL MARKERS ON FIRM GROUND OR ON SAND PADS IF
NEEDED FOR STABILITY . TAKE INITIAL READING ON TOP
OF ROD AND AT ADJACENT GROUND LEVEL PRIOR TO PLACE-
MENT OF ANY FILL .
2 . FOR EASE IN HANDLING, ROD AND CASING ARE USUALLY
INSTALLED IN 5-FOOT SECTIONS . AS FILL PROGRESSES,
COUPLINGS ARE USED TO INSTALL ADDITIONAL LENGTHS .
CONTINUITY IS MAINTAINED BY READING THE TOP OF THE
MEASUREMENT ROD, THEN IMMEDIATELY ADDING THE NEW
SECTION AND READING THE TOP OF THE ADDED ROD . BOTH
READINGS ARE RECORDED .
3 . RECORD THE ELEVATION OF THE TOP OF THE MEASUREMENT
ROD IN EACH MARKER AT THE RECOMMENDED TIME INTERVALS .
EACH TIME, NOTE THE ELEVATION OF THE ADJACENT FILL
J SURFACE .
10 4 . READ THE MARKER TO THE NEAREST 0 . 01 FOOT, OR 0 . 005
Q FOOT IF POSSIBLE . NOTE THE FILL ELEVATION TO THE
NEAREST 0 . 1 FOOT .
N 5 . THE ELEVATIONS SHOULD BE REFERENCED TO A TEMPORARY
p BENCHMARK LOCATED ON STABLE GROUND AT LEAST 100 FEEl'
FROM THE EMBANKMENT .
��� SETTLEMENT PLATE DETAIL
Geo\Engineers FIGURE 6
APPENDIX A
A P P E N D I X A
FIELD EXPLORATIONS AND LABORATORY TESTING
FIELD EXPLORATIONS
The surface and subsurface soil and ground water conditions at the site
were explored by drilling 19 borings at the locations shown in Figure 2.
The boring locations and elevations were determined following drilling by
surveying performed by Wilsey & Ham Pacific.
The test borings were drilled between December 3 and 7, 1990 to depths
of 44 to 89 feet below existing grade. These borings were advanced using
a truck-mounted, continuous-flight, hollow-stem auger drill. Relatively
undisturbed samples were obtained from the borings using a 3-inch-outside-
diameter split-barrel sampler driven into the soil with a 300-pound hammer
free-falling 30 inches. The number of blows required to drive the sampler
the last 12 inches, or other indicated distance, is recorded on the boring
logs. All samples were sealed in containers to limit moisture loss, labeled
and taken to our laboratory for further examination and testing.
The borings were continuously monitored by a representative of our firm
who selected sample intervals, examined and classified the soils recovered,
kept a log of each boring, and monitored the installation of the monitor
wells. Soils encountered were classified visually in general accordance
with the classification system described in Figure A-1. A key to the boring
log symbols is presented in Figure A-2. The logs of the borings are
presented in Figures A-3 through A-42.
The exploration logs are based on our interpretation of the field and
laboratory data and indicate the various types of soils encountered. They
also indicate the depths at which these soils or their characteristics
change, although the change might actually be gradual. If the change
occurred between samples in the borings, it was interpreted.
Six monitor wells were installed as part of our study. The wells
consist of 2-inch-diameter PVC, flush-threaded well casing and screen. Some
of the wells were installed in the original bore holes after backfilling the
lower portion of the holes with a soil-bentonite mixture. For the
remainder of the wells, the drillers moved 3 to 4 feet away from the boring
location and drilled down to the desired installation depth. The wells
extended to depths of 15.5 to 20 feet. The top of the screen was set at a
depth of 5 feet except for Monitor Well 1 which was set at a depth of
A - 1
10 feet. A flush-mounted steel monument was installed over each well. The
details of each monitor well are presented on the Monitor Well logs,
Figures A-43 through A-48. Water level measurements were accomplished on
January 4, 1991. The results of the measurements are presented on the
monitor well logs.
LABORATORY TESTING
All soil samples were brought to our laboratory for further exami-
nation. The samples were examined for evidence of recent movement or
disturbance. Selected samples were tested to determine moisture content,
dry density, gradation, compressibility, and strength characteristics.
Numerous soil samples were tested to determine moisture contents and
dry densities. These determinations were used to correlate various soil
strata and to evaluate the unit weight and degree of saturation of the
I soils. The results of the moisture and density determinations are presented
1 on the boring logs.
Mechanical grain-size analyses were performed on four samples to aid in
classification of granular soils. Gradation curves for these samples are
presented in Figure 49 and 50.
Atterberg limits tests were performed on three samples to aid in
classification of fine-grained soils. The results of the Atterberg limit
tests are presented in Figure A-51.
One-dimensional consolidation tests were performed to measure the
dimensional and time-rate compressibility characteristics of three fine-
grained samples. The consolidation test results are presented in
Figures A-52 through A-54.
Strength characteristics of coarse-grained samples were evaluated by
performing triaxial tests. Strain-controlled triaxial compression tests
were performed on 4 granular samples. The tests were run in a consolidated-
drained manner. The triaxial compression test results are presented in
Figures A-55 and A-56.
A - 2
SOIL CLASSIFICATION SYSTEM
MAJOR DIVISIONS GROUP GROUP NAME
SYMBOL
GRAVEL CLEAN GRAVEL GW WELL—GRADED GRAVEL,FINE TO
COARSE COARSE GRAVEL
GRAINED GP POORLY—GRADED GRAVEL
SOILS MORE THAN 50% GRAVEL GM SILTY GRAVEL
OF COARSE FRACTION WITH FINES
RETAINED
ON NO. 4 SIEVE GC CLAYEY GRAVEL
MORE THAN 50%
RETAINED ON SAND CLEAN SAND SW WELL—GRADED SAND, FINE TO
NO. 200 SIEVE COARSE SAND
SP POORLY—GRADED SAND
MORE THAN 50% SAND SM SILTY SAND
OF COARSE FRACTION WITH FINES
PASSES
NO. 4 SIEVE SC CLAYEY SAND
SILT AND CLAY ML SILT
FINE INORGANIC
GRAINED CL CLAY
SOILS LIQUID LIMIT
LESS THAN 50 ORGANIC OL ORGANIC SILT, ORGANIC CLAY
SILT AND CLAY MH SILT OF HIGH PLASTICITY, ELASTIC SILT
MORE THAN 50% INORGANIC
PASSES NO. 200
SIEVE CH CLAY OF HIGH PLASTICITY, FAT CLAY
LIQUID LIMIT
50 OR MORE ORGANIC OH ORGANIC CLAY, ORGANIC SILT
HIGHLY ORGANIC SOILS PT PEAT
NOTES: SOIL MOISTURE MODIFIERS:
1. Field classification is based on Dry — Absence of moisture, dusty, dry
visual examination of soil in general to the touch
accordance with ASTM D2488-83.
Moist — Damp, but no visible water
2. Soil classification using laboratory
tests is based on ASTM D2487-83. Wet — Visible free water or saturated,
usually soil is obtained from
3. Descriptions of soil density or below water table
consistency are based on
interpretation of blowcount data,
visual appearance of soils, and/or
test data.
co
co
�ps, SOIL CLASSIFICATION SYSTEM
Co Geo Engineers
FIGURE A-1
LABORATORY TESTS: SOIL GRAPH:
AL Atterberg limits
SM Soil Group Symbol
CP Compaction
(See Note 2)
CS Consolidation
DS Direct shear
GS Grain - size Distinct Contact Between
%F Percent fines Soil Strata
HA Hydrometer analysis Gradual or Approximate
SK Permeability Location of Change
SM Moisture content Between Soil Strata
MD Moisture and density
SP Swelling pressure Water Level
TX Triaxial compression Bottom of Boring
UC Unconfined compression
CA Chemical analysis
BLOW-COUNT/SAMPLE DATA:
22 Location of relatively
Blows required to drive a 2.4-inch I.D. undisturbed sample
split-barrel sampler 12 inches or
other indicated distances using a 12 ® Location of disturbed sample
300-pound hammer failing 30 inches.
17 0 Location of sampling attempt
with no recovery
10 ❑ Location cf sample obtained
Blows required to drive a 1.5-inch I.D. in general accordance with
(SPT) split-barrel sampler 12 inches Standard Penetration Test
or other indicated distances using (ASTM D-1566) procedures
140-pound hammer falling 30 inches.
26 m Location of SPT sampling
attempt with no recovery
® Location of grab sample
"P" indicates sampler pushed with
weight of hammer or against weight
of drill rig.
NOTES:
1. The reader must refer to the discussion in the report text, the Key to Boring Log Symbols
and the exploration logs for a proper understanding of subsurface conditions.
2. Soil classification system is summarized in Figure A-1.
m
\� KEY TO BORING LOG SYMBOLS
Geo�Pp Engineers
�/ FIGURE A-2
TEST DATA BORING I
M
►�- .4^ 141 -4 DESCRIPTION
•.4 C•• 7 C p 0 7 E Group
J Fa a X O O a m U � Symbol Surface Elevation(ft.): 12.55
0 vBrown silty fine to medium sand with grave (loose,moist (fill) 0
ML Gray silt(very soft to soft,moist)
MD, 45 76 2
AL
5 5
SM Gray silty fine sand(loose to medium dense,wet)
MD 27 11
10 L 1 ML/ Gray silt with peat to organic silt(soft,moist to wet) 10
i I I OL
I I I
MD 144 33 3 1 1 1
I I 1
I I I 15
15 Ui
I I
I-
W I SM/ Dark gray silty fine sand to fine sandy silt with organic matter
U. - ML (loose,soft,wet)
H MD 40 81 8
IL 20
p20 SP Dark gray fine to medium sand(medium dense to dense,wet)
MD 26 95 27
m
m
25 SW Dark gray fine to coarse sand with gravel and a trace of organic 25
_ _ matter(medium dense,wet)
N
N 23 .
U
N
Q — 30
U 30 SP Dark gray fine to medium sand(dense,wet)
1-
J
Z
35
35 35
LO
m
m 21 Grades to sand with fine gravel
m
m
—40
WN 40
m Note:See Figure A-2 for explanation of symbols
041-14V
� Log of Boring
Ge01al Engineers Figure A-3
TEST DATA BORING 1
N (Continued)
~ c iw 3 J a DESCRIPTION
0 Grou
J EU\ O O a m U N Symbol
40 .J 40
SP — Dark gray fine to medium sand with silt,a trace of coarse sand,
SM fine gravel and shell fragments(medium dense,wet)
MD, 21 102 24
TX,
GS
45 45
27
Boring completed at 485 feet on 12/3/90
Ground water encountered at 6 feet during drilling 50
50
55 55
lu
w
tL
z
H
H
IL 60
0 60
m
m
a 65 65
N
fA
U
U 70 70
F
J
z
75 75
to
m
m
m
m
m
m 80 [80
N
m Note:See Figure A-2 for explanation of symbols
��j Log of Boring
Ge0�P Engineers Figure A-4
TESL'DATA BORING 2
M
4J Y
Y C 4 Y
4J6 "I^ '4 DESCRIPTION
04J IA 0 3 C 0- Group
0 0 0\ L d a .-4i o i Symbl Surface Elevation(ft.): 15.03
p — Brown fine gravel with silt and fine sand loose,moist ill 0
GM
SM/ Black to mottled gray silty fine sand to fine sandy silt(loose,
7 ML medium stiff,moist)
5 5
SP Black fine sand with a trace of silt(loose,wet)
7
10 10
SM Dark gray silty fine sand(very loose,wet)
MD 40 82 3
15 15
w
w
1L
z
H
= 6
F-
a
0 20 20
ILI
m 16 ® SP Black fine to medium sand with a trace of silt(medium dense,
CD wet)
25 25
N
N
VMD 18 109 38 Grades to with a trace of coarse sand
ui
3p 30
J SWI Gray gravelly fine to coarse sand to sandy fine to coarse gravel
z
.. W (medium dense,wet)
20 — —
35 35
to — —
14 SP Gray medium sand(medium dense,wet)
m
m
i
fU 40 40
.a
m Note:See Figure A-2 for explanation of symbols
P'
G e o 1�Engineers Log of
Boring
��� g Figure A-5
TEST DATA BORING 2
a (Continued)
t- +'m •-+.. DESCRIPTION
pal N U 3 C a Group
a 0 0\ L 0 ll -4 0 4 Symbol
J EU- CIO.. m U N
40 - 40
I. SP Black fine sand(dense,wet)
41
4$ SP Gray medium sand with shell fragments(medium dense to dense, 45
wet)
18
Boring completed at 49.0 feet on 12/3/90
50 Ground water encountered at approximately 6 feet during drilling 50
55 55
F-
Ui
W
IL
Z
H
a
0 60 60
m
m
a 65 L65
N
a
N
E
U
N
U 70 70
I
J
Z
75 75
IA
m
to
m
m
m
N 80 SO
4
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Geo MwEngineers
Figure A-6
TEST DATA BORING 2
(Continued)
F- 4.1 m +,. I 4-1 -•I DESCRIPTION
641 M.. 3 C CL Group
i 0 0 L r Q• -4 0 a Symbol
J MU�+ 0 0.. m U N
40 40
SP Black fine sand(dense,wet)
41
45 SP Gray medium sand with shell fragments(medium dense to dense, 45
wet)
18
Boring completed at 49.0 feet on 12/3/90
50 Ground water encountered at approximately 6 feet during drilling 50
55 55
w
w
U.
z
H
a
0 60 60
m
m
14 65 65
N
a
In
F
U
N
70 70
J
z
75 75
IA
m
m
I
m
W
m
I
a 80 L80
.-I
m Note:See Figure A-2 for explanation of symbols
\�/� Log of Boring
Geo%I Engineers
Figure A-6
TEST DATA BORING 3
N
4 N
F si■ .i^ ' V "{ DESCRIPTION
1W N U 3 C CL Group
i 00 0� a i p —4 o i Symbol Surface Elevation(ft.): 1428
0 �' ML inches crushed roc 0
Gray silt(medium stiff,moist)(fill)
5
5 5
® SM Gray silty fine sand(very loose,wet)
3
10 10
MD 69 58 4 ML Gray silt with organic matter and a trace of sand(very soft to
soft,wet)
F- 1$ SM Gray silty fine sand(medium dense,wet) 1$
W
W
LL
Z
H
24
SP Black fine to medium sand(medium dense,wet)
IL
0 20 20
SW Black fine to coarse sand with occasional gravel(medium dense,
wet)
m 17 ® — —
m
.�+ 25 — — 25
N -
- W/ Gray sandy fine to coarse gravel interbedded with gravelly
ul T SW medium to coarse sand(medium dense,wet)
U 17 ® — —
U
30 — — 30
z
MD 11 127 18 —
35 — — 35
N — —
m —
m —
SP Dark gray fine to medium sand(medium dense to dense,wet)
m 33
m
i
N 40 40
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Geo%a Engineers
Figure A-7
TEST DATA BORING 3
N (Continued)
N "1 a N
�a
."I^ �' r DESCRIPTION
Naj N U 3 C 0- Group
0 0 0\ 3 r❑, �0 4 Symbl
J EU� ❑❑.. mU 0)
40 — 40
19
Boring completed at 44.0 feet on 12/4/90
45 Ground water encountered at approximately 6 feet during drilling 45
50 50
F 55 55
w
w
L
z
H
H
a
0 60 60
m
m
65 65
a
z
U
U 70 70
F-
J
z
75 75
m
m
m
m
m
m
N 80 80
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Geo��Engineers Figure A-8
TEST DATA BORING 4
p
+� Y
11 C 4 r
f" 418 'a^ 14J -4 DESCRIPTION
Group
o X L N a —4 O 4 Symbol Surface Elevation(ft.): 18.58
J F0 v OOv mU to
pMottled grayish-brown sandy silt with a trace of roots very sot 0
to soft,moist to wet)
MD 45 74 2
5 SP— Brownish-gray fine sand with silt(very loose to loose,wet) 5
SM
2
10 10
8
15 15
WSP Dark gray fine sand(medium dense,moist)
W
W
H 20
H
IL
0 20 SP Black fine to medium sand(loose,wet) 20
6
m
m
25 25
N
F MD 30 77 8
U
N
c¢i 30 30
J
Z
8
35 35
SP Black fine to medium sand(medium dense to dense,wet)
ID
m
m 36 .
m
40
m
i
m 40
N
a
m Note:See Figure A-2 for explanation of symbols
gip. Log of Boring
Geo%Q Engineers Figure A-9
TEST DATA BORING 4
(Continued)
>C 41
~ +J0 "1^ 141 -i DESCRIPTION
ow M U 3 C t1 Group
4 0 0\ L 8 p. -4 0 4 Symbl
J r-U.. 00 MU U)
40 40
41
45 45
32
50 50
SP-SM/.
SM ark gray interbedded fine sand with silt to silty fine sand
(medium dense,wet)
37
F 55 55
w
w
tl
z
H 17
2
H
a
60 ML Gray fine sandy silt with occasional shell fragments(medium stiff, 60
wet)
MD 37 83 7
m
rn
a 65 SP— Gray fine sand with silt and occasional shell fragments(medium 65
N - SM dense,wet)
F 29
U
N
Cal 70 SP Gray fine sand with occasional wood fragments(medium dense to 70
dense,wet)
J
Z
34
75 - SW Gray fine to coarse sand with gravel and a trace of shell 75
fragments(very dense,wet)
m —
tn MD 9 130 55
m — —
m
m — —
a 80 - 80
a
m Note:See Figure A-2 for explanation of symbols
��j Log of Boring
Geo po Engineers
Figure A= 10
TEST DATA BORING 4
(Continued)
�- +'d DESCRIPTION
IW� M U 3 C Q Group
4 0 0\ L i a --4 0 , Symbol
80 80
55 ,
Boring completed at 93.5 feet on 12/4/90
85 Ground water encountered at approximately 6 feet during drilling 85
90 L90
95 95
w
w
LL
z
H
IL
&00 100
m
m
I-
105 105
N
a
(n
U
N
110 110
J
z
115 115
N
m
m
m
W
m
10
120 120
a
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Ge0��Engineers Figure A-11
TEST DATA BORING 5
M
+� d
IMI 7 4 d
E' +id "A^ *' i DESCRIPTION
IW M 0 3 C a Group
0 0 0\ LL 6 tl -1 0 0 Symbol Surface Elevation(ft.): 13.70
J r-U�+ ❑o— mU W
0 ML inches asphalt concrete underlain by brown silty fine to medium 0
sand(medium dense,moist)(fill)
Dark gray silt with a trace of sand(soft to medium stiff,moist)
MD 34 87 4 ■
5 5
SM/ Dark gray silty fine sand to silt with sand(very loose,soft,wet)
ML
2 ■
10 10
SP Black fine sand with a trace of silt(very loose to loose,wet)
MD 31 91 4 ■
15 15
w
w
w
H 11 ■
f-
a
Uj 20 SP Black fine to medium sand with a trace of silt(dense,wet) 20
MD, 22 103 31 ■
TX,
GS
25 25
to
U29 ■ Grades to sand with fine gravel
Q
30 30
J
Z
40 ■
35 35
N
m
m 21 ■
m
rn
m
N
a
m Note:See Figure A-2 for explana on of symbols
Log of Boring
Ge0%r Engineers Figure A-12
TFST DATA BORING 5
a (Continued)
I— ++a •-+„ 1 4-1 -4 DESCRIPTION
so a U 3 C a Group
0 p p X L o a —4i o 1 Symbol
J ZU v 0
0v mU Ul
Dark gray fine to medium sand with shell fragments medium 40
dense,wet)
23
45 45
23
50 SW/ Gray gravelly fine to coarse sand to sandy fine to coarse gravel 50
W (very dense,wet)
MD 10 131 50 _
55 _ _ 55
U
w - -
U-
H 45 — —
= Boring completed at 58.5 feet on 12/3/90
dGround water encountered at a depth of about 6 feet during
wo 60 drilling 60
m
rn
65 65
N
N
F
U
N
70 70
I—
J
Z
75 75
N
m
In
I
m
W
tD
1
a 80 80
m Note:See Figure A-2 for explanation of symbols
11 /to. Log of Boring
Geo Engineers
Figure A-13
TEST DATA BORING S
M
0 3C 4
4J6 "4^ 141 --1 DESCRIPTION
tW Oh- 3 C CL Group
J EU N OO oO a ro U M Symbl Surface Elevation(ft.): 17.27
..
0 Brown sandy silt with wood fragments medium stiff,moist ill 0
6
5 5
7
10 SM Black silty fine sand with occasional layers of fine sand(loose, 10
wet)
MD 32 87 6
15 15
w
w
w
z
H
= 12 ■
n.
0 20 20
m 2 ❑
rn
-�, 25 25
N
OL/ Gray organic silt with lenses of dark brown peat and sand(soft,
U MD 181 28 6 ■ PT wet)
ui
L) 30
W Gray fine to coarse gravel with sand(very dense,wet) 30
z
53
35 35
SW— Gray fine to coarse sand with silt,gravel and a trace of organic
LO — Y- SM matter(medium dense to dense,wet)
m —
M
MD, 13 118 30 ■ —
m
N 40 GS 40
.a
m Note:See Figure A-2 for explanation of symbols
gip•. Log of Boring
Geo\'Engineers
Figure A-14
TEST DATA BORING 6
(Continued)
4
1' 4'r "4^ 14' -1 DESCRIPTION
64-1 NU 3C d Group
a 0 0\ E d -9 O GE Symbl
40 40
42
45 SP Gray fine to medium sand(dense,wet) 45
37
Boring completed at 49.0 feet on 12/3/90
50 Ground water encountered at approximately 6.5 feet during 50
drilling
55 55
to
w
LL
z
H
I
f
a
0 60 60
m
m
a 65 65
N
.4
N
E
U
N
0 70 70
h-
J
z
75 75
L
m
to
m
rn
m
a 80 80
a
m Note:See Figure A-2 for explanation of symbols
gip•. Log of Boring
Ge0%ft Engineers Figure A-15
TEST DATA BORING 7
M
+� r
Oal 7 4-J so
41a "'^ '*' --I DESCRIPTION
Group
4 o o X ?i a —f o i Symbol
J ZO D o_ M L) (n
0 inches asphalt concrete and inches crushed roc 0
SP— Dark gray fine sand with silt(very loose,wet)(fill?)
SM
3
5 5
ML Gray silt with organic matter and lenses of peat(soft,moist)
MD 57 66 3
10 10
SM/ Interbedded dark gray silty fine sand and brown silt with peat
ML (loose,soft,wet)
12
15 15
w
SP Black fine to medium sand with wood fragments(loose,wet)
LL
H
= MD 48 69 6
a
0 2p 20
SP Black fine to medium sand with occasional chunks of wood
(medium dense,wet)
m 30
Ol
.�+ 25 25
N
W
U32 Grades to fine sand
N
0 30 30
z
27 Grades to fine to medium sand
35 35
SP— Gray fine to medium sand with silt(medium dense,wet)
to SM
m
m
i
MD 23 103 26
m
N 4
m Note:See Figure A-2 for explanation of symbols
\
�4 Log of Boring
Ge0\�Engineers Figure A-16
TEST DATA BORING 7
(Continued)
3C 4
l' 410 'a^ 1 a0 "i DESCRIPTION
1W M U 3 C CL Group
4 0 0\ a 8 p -0i 0 f Symbol
J EU ❑O.. mU (0
40
SP Dark gray interbedded fine sand and fine to medium sand 40
(medium dense,wet)
26
45 45
21 ■
50 50
27
55 55
w
w
LL
z
H
= MD 24 100 38 ■
EL Boring completed at 59.0 feet on 12/5/90
WO C0 Ground water encountered at approximately 10 feet during 60
drilling
CP
w
a 65 65
N
a
N
U
N
0 70 70
J
z
75 75
a
m
m
m
m
m
N 80 80
a
m Note:See Figure A-2 for explanation of symbols
Ito• Log of Boring
Geo��Engineers
Figure A-17
TEST DATA BORING 8
2
:3 C 4
4J8 .-1.. DESCRIPTION
041 M4- 3 C a
..4r 3ru 03 E Group
4 0 0 X L NCL —413 4 Symbol Surface Elevation(ft.): 16.43
_1 ro 0 0— MU to
0- ML Brownish-gray sandy silt with a trace of organic matter(medium 0
stiff,moist)(fill?)
8
5- -5
SP Black fine to medium sand(loose to medium dense,wet)
6
10 - 10
MD 26 92 8
15 - -15
W
W
IL
z
H
Grades to medium sand
F-
L'j 20 -20
0
8 Grades to fine sand
25 - -25
21
ui
<1
30 -30
_j
z
9 Grades to with occasional wood fragments
35 - -35
SP Gray fine to medium coarse sand with a trace of fine gravel
Lo (dense,wet)
ED
35
to
0
L40
40
Note:See Figure A-2 for explanation of symbols
AA 01, Log of Boring
Geo*PmmEnneers,.;w 0 Figure A-18
TEST DATA BORING 8
tl (Continued)
C
~ 'iN 'a^ I 'J -4 DESCRIPTION
kw N 0 3 C '- Group
s ooX i@a -#o s Symbol
J FU O G.. m U fl1
40 40
35
SP— Gray fine to medium sand with silt(dense,wet)
SM
45 SP Gray medium sand with occasional shell fragments(medium 45
dense,wet)
MD 22 104 25
SM Gray fine to medium silty sand with occasional shell fragments
(medium dense,wet)
50 50
'. SW Gray fine to coarse sand with a trace of silt,occasional gravel and
shell fragments(dense,wet)
42 — —
55 - - 55
w - -
w
IL - -
z - -
H
= 32 — —
a Boring completed at 59.0 feet on 12/7/90
O60 Ground water encountered at approximately 5 feet during drilling 60
m
U
65 65
N
N
E
U
to
70 70
H
J
Z
75 75
to
m
m
i
m
W
m
i
N 80 L80
a
m Note:See Figure A-2 for explanation of symbols
gip•- Log of Boring
Geo14 E-Pw veers
Figure A-19
TEST DATA BORING 9
M
r 7 �
4.)8 'a^ 1 4.) -a DESCRIPTION
pa+ M U 3 C CL Group
i 0 0 X L i tl --1 o 4 Symbol Surface Elevation(ft.): 16.86
J ZU DO— MU N
0Brown silty fine sand medium dense,moist 0
13
5 5
SM/.Grayish-brown silty fine sand to fine sand with silt(very loose to
SP-SM loose,wet)
MD 32 86 2
10 10
4
15 15
w
w
1L SP/ Black interbedded fine sand with a trace of silt and fine sand with
Z SP-SM silt(loose,wet)
H
= 9
f-
a
0 20 20
m 14 Grades to medium dense
0)
25 25
N
.a
to
U 14
N
L) 30 30
J
Z
MD 30 93 18 Grades to sand with occasional wood fragments
35 35
a
m
to
m16
N 40 r 40
m Note:See Figure A-2 for explanation of symbols
\�� Log of Boring
Ge0��Engineers Figure A-20
TEST DATA BORING 9
(Continued)
41a DESCRIPTION
par p 3 C a Grou
0 o o X a i p, —4 o i Symbol
J EU Cl o— m U Ul
Gray silty fine to medium sand with pockets of fine to coarse 40
sand and occasional shell fragments(medium dense,wet)
25
45 45
35
Grades to dense
Boring completed at 49.0 feet on 12/7/90
50 Ground water encountered at approximately 73 feet during S0
drilling
55 55
w
w
lL
z
H
H
IL
o 6Q 60
CD
1 65 65
N
N
E
U
N
0 7Q 70
F-
J
Z
75 75
N
m
I
tD
I
a 8Q 80
.I
m Note:See Figure A-2 for explanation of symbols
`J Log of Boring
Geo\r Engineers
Figure A- 21
TEST DATA BORING lO
_\ N
++ N
0 C 41 N
F- 4J0 •.4^ 141 -1 DESCRIPTION
ow Or,..
3 C CL Group
0 0 X, L o a -4 O 4 Symbol Surface Elevation(ft.): 16.46
J F_U d 0— MU to
0 ark brown silty sand loose,moist topsoil 0
ML Gray silt with organic matter and lenses of peat(soft to medium
stiff,moist to wet)
MD 97 64 6
5 ML Gray silt with a trace of organic matter(very soft to soft,wet) 5
MD, 44 77 2
CS,
AL
10 10
2
r+► H 15 SP Dark gray fine to medium sand(medium dense to dense,wet) 15
W
W
LL
H 18 .
2
F-
0 20 20
MD 26 98 20
m
m
a 25 25
N
E
34 .
z. U
N
L) 30 30
J
Z
36 .
35 35
m
m 14
—40
m
a 40
a
m Note:See Figure A-2 for explanati n of symbols
its
Log of Boring
Ge0 l%Engineers Figure A-22
TEST DATA BORING 10
(Continued)
41
410 'a^ '*' —4 DESCRIPTION
at p a U 3 C a Group
s —jr
o X a 8 a -Ci o i Symbol
J M 00— MU N
Dark gray fine to medium sand with shell fragments medium 40
dense to dense,wet)
30
45 45
29
50 50
SW/ Gray fine to coarse sand with gravel to sandy gravel(dense,wet)
W
46
F 55 W Gray fine to coarse gravel with sand(medium dense,wet) $5
w
W
LL �
H M. 8 22
IL �.
0 60 SW Gray fine to coarse sand with gravel(dense,wet) 60
33 —
m —
rn
a 65 - 65
N —
a
42 — —
U — —
Q _
U 70 70
J
Z — —
67 , Grades to very dense
7S SP Gray fine to medium sand(medium dense,wet) 75
IA
m
m
m 28 Boring completed at 78.5 feet on 12/4/90
mGround water encountered at approximately 5 to 6 feet during
drilling
a 80 80
m Note:See Figure A-2 for explanation of symbols
/ts. Log of Boring
Geo\W Engineers
Figure A- 23
TEST DATA BORING 11
N
41 N
INI 3 C 4 r
H 4J N •a.. DESCRIPTION
1W N U 3 C IL Grou
s 00 X 3N tl -4 0 6 Symbol Surface Elevation(ft.): 16.49
ML Mottled brown and gray silt with occasional pieces of gravel so t, 0
moist)(fill?)
4
5 ML Gray silt with a trace sand and organic matter(very soft to soft, 5
wet)
MD 47 74 2
10 10
SM/ Gray interbedded silty fine sand to fine sandy silt(loose,soft to
ML medium stiff,wet)
6
H
15 SM Gray silty fine sand(loose,wet) 15
W
W
W
H 9
H
a
❑ 20 SP— Grayish-black fine sand with silt(medium dense,wet) 20
- SM
29
0) SP Black fine to medium sand with a trace of silt(medium dense,
25 2$
p\p wet)
fA 25
F
U
N
30 30
J
Z
31
35 35
rn
m
MD 18 109 21 SP— Gray fine to medium sand with a trace of coarse sand and shell
SM fragments(medium dense,wet)
40
N 4
.a
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Ge0 M.Engineers Figure A-24
TEST DATA BORING 11
(Continued)
Uj C 4 i
�- ++r •a - DESCRIPTION
0+1 M.. 3 C a Group
a o o\ a i p_ ---I o 4 Symbol
J r.U.. 00.. MU N
40 40
21
45 45
MD, 18 109 29 �
Tx
50 50
44 , Grades to dense
F 55 55
w
w
H 19 ❑
H
O60 SW Gray fine to coarse sand with occasional gravel(dense,wet) 60
45 ® _
65 65
40 ❑ - -
U
Boring completed at 68S feet on 12/7/90
U70 Ground water encountered at approximately 6 feet during drilling 70
H
J
Z
i
75 75
to
m
m
1
m
W
m
I
N 80 80
m Note:See Figure A-2 for explanation of symbols
\�� Log of Boring
Ge0\w Engineers Figure A-25
TEST DATA BORING 12
1
++ •
4
~ 41r 'a^ *� DESCRIPTION
pay M.. 3 C CL Group
0 o o a r t1 -4 o i Symbol Surface Elevation(ft.): 16.06
J EU.. 00.. mU N
inches asphalt concrete underlain by 4 inches crushed rock 0
SM Brown silty fine sand(very loose,moist)
4
5 5
SP— Black fine sand with silt(loose,wet)
SM
5
10 10
OL Brown organic silt(soft,moist)
MD, 101 60 4
CS I I I
15 I I ► 15
wML/ Gray silt with layers of black fine sand(soft,loose,wet)
U- SP
Z
H
= 5
H
a
0 20 20
SP Black fine to medium sand(loose,wet)
m 7
m
25 25
N SP Black fine to medium sand(medium dense,wet)
N
U MD 24 101 24
vi
L) 30 30
i`
J
Z
31
35 35
m
m
m
32 Grades to sand with a trace of shell fragments
m
i
cu 40 L40
m Note:See Figure A-2 for explanation of symbols
l►�. Log of Boring
Geo��Engineers
Figure A-26
TEST DATA BORING 12
N (Continued)
m C
F- air a^ 4J -4 DESCRIPTION
NW N U 3 C 0.
0 0 0\ LL 8 0- --1i 0 a Symb Group
J EU.. 00- mU U1
40 40
29
45 SP Dark gray fine sand(medium dense,wet) 45
i
20
50 50
MD 23 102 25
55 55
w
w
tL
z
H
73 . Blow count may not be representative of soil encountered
F-
a
0 60 60
40 Grades to dense
m
m
65 65
N
a
N
U 56
in
70 70
J
z
53
75 75
m ` SW Dark gray fine to coarse sand with gravel and shell fragments
m _ (dense,wet)
m 45 _ Boring completed at 79.0 feet on 12/4/90
mGround water encountered at approximately 6.5 feet during
® drilling
a 80 80
m Note:See Figure A-2 for explanation of symbols
0A IM Log of Boring
Geo Engineers
Figure A-27
TEST DATA BORING 13
N
C 4-j •
F- ++N •-q— 1 +' —1 DESCRIPTION
Nj N 0 3 C C.
D0 X L N tL -4 o s Symb Grouol Surface Elevation(ft.): 15.75
J r_U 0 CI.. m U U)
0Mottled brown and gray silt(soft,moist 0
MD 41 78 2
5 5
SP— Gray fine sand with silt(very loose,wet)
- SM
2
10 _ 10
ML Dark gray fine sandy silt with a trace of peat(soft,wet)
3
15 15
w
w
IL
H MD 56 3 . Grades to silt with organic matter
H
EL 20
O 20 SP Black fine to medium sand(medium dense,wet)
14
m
m
t- 25
.�i 25
N
E MD 22 105 19
U
N
30 30
J
Z
24
35 35
m
m 20
40
m
N 40
.i
m Note:See Figure A-2 for explanation of symbols
\A Log of Boring
Ge0 Engineers Figure A-28
TEST DATA BORING 13
(Continued)
H 4j r •-4. DESCRIPTION
R+J M
J 3 C CL
f U aCU -0i Group
0 \ Itl —i Symbol
EU.. a0— MU to
4Q 40
Sp Dark gray fine to medium sand with silt to fine to medium sand
with a trace of shell fragments(medium dense,wet)
16
45 45
SP Gray fine to medium sand with a trace of shell fragments and
21 peat(medium dense,wet)
50 50
10
55 55
w
w
IL
H MD 34 96 17
H
a
Lou 60 60
26
a) Boring completed at 63.5 feet on 12/6/90
Ground water encountered at approximately 6 feet during drilling
a 65 65
IU
fn
E
U
N
U 70 70
H
J
Z
75 75
IO
m
m
i
m
to
m
N $Q 80
.a
m Note:See Figure A-2 for explanation of symbols
Log of Bo
ring
orin g
Ge0 Mr Engineers Figure A-29
TESL'DATA BORING 14
p
4J •
W 3C 4
41a 'a^ ' *' —4 DESCRIPTION
041 M U 3 C a Group
4 0 0\ ;i p, —4 o 4 Symbl Surface Elevation(ft.): 18.01
J ZU�+ 00— MU N
0Mottled brown sandy silt with a trace of organic matter(soft, 0
moist)
4
SM Mottled brown silty fine sand(loose,moist to wet)
5 5
9
10 SP Black fine to medium sand(medium dense,wet) 10
MD 27 97 11
15 15
w
to
tL
z
H
= 15
F—
a
0 20 20
20
Lens of peat at 23.5 feet
25 25
N
N
U 18
N
Q
30 30
J
z
23 Grades to fine sand
35 35
LD
m
m
m Grades to sand with occasional wood fragments
m
m
i
N
.a
m Note:See Figure A-2 for explanation of symbols
%MM�nP• Log of Boring
Geoff Engineers
Figure A-30
TEST DATA BORING 14
(Continued)
3C
F- a''u DESCRIPTION
Ike Oil.. 3 C CL Group
q 00\ ?ICI a --i 0 i Symbol
J F_tJ.. ❑CI.. m U N
40 40
SM Gray silty fine sand with a trace of shell fragments(medium
dense,wet)
14
45 45
MD 28 96 23
50 SM Gray silty fine sand with a trace of organic matter(medium 50
dense,wet)
14 ■
55 55
w
w
IL
z
H
= 27 ■
IL
Lou 60 60
m 18
Boring completed at 64.0 feet on 12/7/90
I- 65 Ground water encountered at approximately 6 feet during drilling 65
a
a
N
F
U
U1
0 70 70
h
J
z
75 75
N
m
m
I
lD
0)
m
I
a 80 80
a
m Note:See Figure A-2 for explanation of symbols
\�j Log of Boring
Geo�p Engineers
Figure A-31
TEST DATA BORING 15
M
4� •
C 4i
F- 4 8 .-I DESCRIPTION
tuj_ a- 3 C a Group
4 0 0\ L m a �0 4 Symbl Surface Elevation(ft.): 18.02
J C1 E l0 U fA
ML Mottled gray and brown silt with a trace of sand and organic 0
matter(very soft to soft,moist to wet)
2
5 5
3
10 10
MD 48 73 3 , Grades to gray silt
15 15
w
w
tL
Z SM Gray silty fine sand(medium dense,wet)
H 14
2
H
a
0 20 SM� Interbedded gray silty fine sand and fine sandy silt(very loose, 20
- ML wet)
3
m
m
.+ 25 SP— Black fine to medium sand with silt(medium dense,wet) 25
N SM
a
E MD 22 19
U
N
U 30 SP Black fine to medium sand with a trace of silt(medium dense, 30
J
wet)
Z
15
i
35 35
LD
m
m 17
m
m
CD
N 4
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Ge0%P.,Engineers Figure A-32
TEST DATA BORING 15
(Continued)
f- +rN 'a— 1 +-j 'a DESCRIPTION
W M U 13 3 C CL Grow
f 0 0\ 6 a —4i 0 4 Symbol
J EU�+ 0❑.. MU N
4040
27
45 45
SP Gray fine to medium sand with a trace of shell fragments
(medium dense,wet)
29
50 50
29
55 55
lu
w
1L
H 21
H Boring completed at 58.5 feet on 12/7/90
IL Ground water encountered at approximately 6 feet during drilling
o 60 60
m
m
65 65
N
N
E
U
N
U 70 70
H
J
Z
75 75
a
m
to
m
m
m
a 80 80
m Note:See Figure A-2 for explanation of symbols
gip• Log of Boring
Geoo Engineers 3
Figure A_ 3
TEST DATA BORING, 16
M
� M
d C � i
+'M •a.. +' DESCRIPTION
Ma+ M- 3 C CL Group
0 00 X a i tl -4 O i Symbol Surface Elevation(ft.): 19.54
J EU.. CIO.. MU N
0 / Interbedded fine sandy silt and silty fine sand with roots(soft, 0
SM loose,moist)
MD 33 78 3
5 ML Gray silt with fine sand(very soft to soft,wet) 5
2
10 10
1 �
15 15
WML Gray silt with lenses of peat(soft,wet)
Z
H MD 64 61 3
H
EL
o 20 20
4 Grades to with lenses of fine sand
m
m
25 25
N
..a
SP Black fine to medium sand(medium dense,wet)
E 29
U
U
3p 30
J
Z
MD 24 101 31
35 35
m
140
401
m �
m
m
m
N
m Note:See Figure A-2 for explanation of symbols
\� Log of Boring
Ge0�P.1.0 Engineers Figure A-34
TEST DATA BORING 16
(Continued)
p S.N JI M
01 7 C a0 ■
-W■ 'a^ DESCRIPTION
0 4J_ M U 3 C CL Group
4 0 0.X L1 M a -4 o 4 Symbol
J
40 40
14 El
45 45
SP— Gray fine sand with silt and a trace of organic matter(medium
12 , SM dense,wet)
50 50
MD 23 101 20
55 55
w
w
w
H 12 ® Grades to sand with shell fragments
f-
IL
Wo 60 MLA Gray fine sandy silt to silty fine sand(medium stiff,loose,wet) 60
- SM
6
m
m
t`
\ 65 - SM Gray silty fine sand(medium dense,wet) 65
N
F 22
U
N
C
U
F 70 SP— Gray fine sand with silt(dense,wet) 70
J SM
Z
39
Boring completed at 73.5 feet on 12/6/90
75 Ground water encountered at approximately 6 feet during drilling 75
N
m
07
i
m
W
m
i
a 80 80
a
m Note:See Figure A-2 for explanation of symbols
gip• Log of Boring
Geo po Engineers
Figure A-35
TEST DATA BORING 17
M
+� r
0 7 4j ■
4'd 'a— I4J —4 DESCRIPTION
1W O 0 3 C CL Group
i 00\ L d tl -4 0 i Symbol Surface Elevation(ft.): 17.52
J r_o.. ❑ — Co m
0Mottled brown silt with a trace of organic matter very sot to 0
soft,moist)
MD 44 76 2
5 5
4 ® SP— Black fine to medium sand with silt(loose,wet)
SM
10 10
11
15 15
WSP Black fine to medium sand with coarse sand and wood fragments
U. (loose,wet)
z
H
= MD 45 74 9
H
a
O20 SP— Gray fine sand with silt(medium dense,wet) 20
- SM
W
11 25 SP Black fine to medium sand(dense,wet) 25
N
a
N
U 32
ui
0 30 30
J ML Gray silt(stiff,wet)
z
12 SP Black fine to medium sand(medium dense,wet)
35 35
m
m
m
m 17 ® Grades to with shell fragments
m
m
i
N 40 40
.i
m Note:See Figure A-2 for explanation of symbols
Log of Boring
Ge0 4g.1.0 Engineers Figure A-36
TEST DATA BORING 17
(Continued)
wi
4
E- 41v "I� 'i DESCRIPTION
64_ a U 3[ a Group
4 00\ L 0 tl -4 0 11 Symbol
J r_C.1— O❑— MU to
40 40
SM Gray silty fine sand with a trace of organic matter and shell
fragments(loose to medium dense,wet)
MD 28 95 S ■
45 45
15 ■
50 50
17 ■
55 55
btu SP— Dark gray fine to medium sand with silt(dense,wet)
tL SM
Z
H
_ 3 ■
H
p6O SP Gray fine to medium sand(dense,wet) 60
m 40
Boring completed at 64.0 feet on 12/6/90
a 6$ Ground water encountered at approximately 6 feet during drilling 65
tU
N
F
U
N
U 70 70
F-
J
Z
75 75
L
m
to
m
m
m
a 80 80
4
m Note:See Figure A-2 for explanation of symbols
\� Log of Boring
Ge0 wal Engineers Figure A-31
TEST DATA BORING 18
M
Y C 4j •
~ *'• —4— 1*' -i DESCRIPTION
041 0.. 3 C D. Group
i DO X ?8 a a 0 4 Symbl Surface Elevation(ft.): 19.35
J IM v 00v 100 to
Mottled brown silt with fine sand and a trace of organic matter 0
(very soft,moist)
MD 44 75 2
5 5
SP Dark brown to black fine sand with a trace of silt(loose to
12 medium dense,wet)
10 10
9
15 15
w
w
IL SP Black fine to medium sand(medium dense,wet)
Z
H
= MD 25 99 21
a
0 20 20
m 20
m
25 25
N
a
N
v 24 , Grades to sand with lenses of brown silt with organic matter
N
L) 30 30
J
Z
MD 23 101 38 Grades to fine to medium sand
35 35
w
m
tD
m 29
Co
N 401 Ll
.i
m Note:See Figure A-2 for explanation of symbols
MP. Log of Boring
Geo qgap Engineers
Figure A-38
TEST DATA BORING 18
p (Continued)
a L4j 3 m
+'d a,- ' +' 'a DESCRIPTION
0 Group
0 X L m a -1i o 4 Symbol
J ED ❑Ov mU N
4040
29
45 45
7 CU Gray interbedded clay and silty fine sand(medium stiff,medium
SM dense,wet)
5p 50
MD, 40 79 4 Grades to soft and loose
CS,
55 `L 55
w
w
1L
z
H
= 9 Grades to silty fine sand with a trace of organic matter
IL 60
060
11 Grades back to clay with lenses of silty sand
°�' 65 65
a
to
U 8
N
U 7p 70
F- SM Gray silty fine sand with a trace of shell fragments(loose,wet)
J
z
MD 29 93 7
75 75
m
m
m
m 6
m
i
a 80 80
a
m Note:See Figure A-2 for explanation of symbols
AM- Log of Boring
Ge0 me -Engineers Figure A-39
TEST DATA BORING IS
i (Continued)
w L4-J 3 r
41 m ��^ � '� "�� DESCRIPTION
p+� M U 3 C ' Group
0 0 0 sL i a. -1 0MC) i Symbl
80 80
SP— Gray fine to medium sand with silt (dense,wet)
SM
30
S5 W/ Dark gray fine to coarse gravel with sand to gravelly fine to 85
SW coarse sand(very dense,wet)
45 _
Boring completed at 89.0 feet on 12/5/90
90 Ground water encountered at approximately 5.5 feet during 90
drilling
F 95 95
w
w
w
z
H
H
EL
R100 100
m
0)
105 105
N
a
F
U
N
U 110 110
H
J
Z
115 115
m
m
m
m
m
m 120 120
a
m Note:See Figure A-2 for explanation of symbols
Lo
g og of Boring
Ge0 qqwl Engineers Figure A-40
TEST DATA BORING 19
a
4J a
Y C +i
H +im •-1^ 1 ++ -4 DESCRIPTION
1W_ p U 3 C CL Group
i 0 a L C tl ---+0 4 Symbl Surface Elevation(ft.): 17.18
Mottled gray sandy silt with occasional organic matter very soft, 0
wet)
2
5 5
2 ® SP/S
• � ark gray interbedded fine sand,silty fine sand and silt(very
loose,soft,wet)
10 10
4
15 OL/ Brown organic silt to peat(stiff,wet) 15
W PT
w
L
Z
H
= MD 65 59 11 SM Gray silty fine sand with a trace of organic matter(loose to
1- medium dense,wet)
a
o 20 20
9
SP Black fine to medium sand(loose,wet)
\ 25 SP Black fine to medium sand with a trace of organic matter 25
(U (medium dense,wet)
!n
U MD, 21 104 28
U1 TX
30 30
J
Z
31
35 35
a
m
M
m MD 25 98 26 . Grades to with occasional layers of silty fine to medium sand
W
m
i
N 4
m Note:See Figure A-2 for explanation of symbols
\� Log of Boring
Geo ngineers
Figure A41
I
TEST DATA BORING 19
(Continued)
C 4
f- 4J8 "-I^ *' { DESCRIPTION
541 6, 3 C CL s o L: goiGrou o Symbol
J EU ❑A
m U 1
40 40
33
45 45
26
Grades to with a trace of shell fragments
50 50
SM/ Gray interbedded silty fine sand and sandy silt(loose,moist,wet)
: ML
6
SP—SM/
55 SM Gray fine to medium sand with silt to silty fine sand with 55
F occasional chunks of wood(medium dense to dense,wet)
W
lu
LL
Z
H
= MD, 29 94 27
H
0 60 GS 60
m MD 24 101 34
m -
\ 65 :- SP Gray fine to medium sand(dense,wet) 65
N
In
U 39
Q Ll
Boring completed at 69.0 feet on 12/6/90
U 70 Ground water encountered at approximately 6 feet during drilling 70
H
J
Z
75 75
LO
m
M
m
m
m
a 80 80
m Note:See Figure A-2 for explanation of symbols
-� Log of Boring
%Ge0 mqvp Engineers Figure A-42
MONITOR WELL NO. MW-1
WELL SCHEMATIC I 4J 3 C aDESCRIPTION
0 3 E Grou
M p
I 0 a V)4 Symbol Surface Elevation(ft.): 12.55
0
.7Steel surface Refer to log of Boring B-1 for soil conditions encountered
monument and Water level at a depth of 4.73 feet on 1/4/91
concrete
Bentonite seal
. 2-inch Schedule 40
5- PVC solid pipe 5
10 -10
-
2-inch Schedule 40
PVC screen,
0.020-inch slot
width
15 - -15
LIJ
W —Medium sand
U_
backfill
z
H
F-
IL
wo 20 — Base of well at 20 -20
feet -
0)
\ 25 - 25
OD
(n
<1
0 30 - 30
z
35 - -35
0)
L4
40 0
Note:See Figure A-2 for explanation of symbols
I Log of Monitor Well
;aONN
PO-0;
Geo,%o- Engineers Figure A43
MONITOR WELL NO. MW-3
WELL SCHEMATIC
3 C CL DESCRIPTION
0 r) G u
:3 E
--1 0 (4 S o� Surface Elevation(ft.): 14.28
M L)
- 7Steel surface Refer to log of Boring B-3 for soil conditions encountered 0
monument and Unable to measure water level due to locked casing(locked
concrete by others)
Bentonite seal
2-inch Schedule 40
5— PVC solid pipe -5
2-inch Schedule 40
10 PVC screen, —10
0.020-inch slot
width -
Medium sand
backfill
15 —15
W Base of well at 15.5
W
feet
z
EL
UO' 20 — —20
0)
25 — —25
00
to
L) 30 —30
z
35 — —35
LD
0)
L
40 40
—
Note:See Figure A-2 for explanation of symbols
its. Log of Monitor Well
K�Vlm
Geo vo,.Engineers
Figure A-44
MONITOR WELL NO. MW4
WELL SCHEMATIC
4-) DESCRIPTION
3 C CL
0 0
3 E Group
.4 0 (4 Symbol Surface Elevation(ft.): 18.58
M L)
Steel surface 0
monument and Refer to log of Boring B-4 for soil conditions encountered
.red
Water level at a depth of 6.54 feet on 1/4/91
concrete
Bentonite seal
.7. 2-inch Schedule 40
5 PVC solid pipe 5
-
10 -
2-inch Schedule 40 10
PVC screen,
0.020-inch slot
width
15 - -15
W
Uj —Medium sand
LL
backfill
z
(L
o 20 Base of well at 20 -20
feet -
a)
25 - 25
(n
<1
0 30 - -30
_j
z
35 - -35
LO
CD -
M I -
40 L40
a
14
Note:See Figure A-2 for explanation of symbols
ZA�
w its- Log of Monitor Well
�
Geo
,.,Enoineers
PW 0 Figure A45
MONITOR WELL NO. MW-11
WELL SCHEMATIC
3 C CL DESCRIPTION
0 :1 E Group
4 a (4 Symbol Surface Elevation(ft.): 16.49,
M 0 n
Steel surface 0
monument and Refer to log of Boring 11 for soil conditions encountered
Water level at a depth of 6.79 feet on 1/4/91
concrete
Bentonite seal
2-inch Schedule 40
5- PVC solid pipe -5
10 - 2-inch Schedule 40 10
PVC screen,
0.020-inch slot
width
15 - -15
Medium sand
Ui backfill
U.
z
H
F-
EL
LLJ
0 20 Base of well at 20 20
feet
25 - -25
(n
(n
C
30 - -30
z
35 - -35
ID
rn
40 L 40
-
Note:See Figure A-2 for explanation of symbols
\�� Log of Monitor Well
Geo %pUngineers
Figure A46
MONITOR WELL NO. MW-12
r
WELL SCHEMATIC r
3 C a DESCRIPTION
0 7 E Group
m U 4 Symbol Surface Elevation(ft.): 16.06
0 Steel surface 0
Refer to log of Boring B-12 for soil conditions encountered
monument and Water level at a depth of 4.12 feet on 1/4/90
concrete '
Bentonite seal
2-inch Schedule 40
5 PVC solid pipe 5
2-inch Schedule 40
,r 10 PVC screen, 10
0.020-inch slot
width
Medium sand
backfill
15 15
W Base of well at 15.5
LL feet
Z
M
H
a
o 20 20
°�' 25 25
a)
to
U
N
30 30
9
J
Z
35 35
LO
m
m
m
m
m
N 40 40
.4
m Note:See Figure A-2 for explanation of symbols
Mu• Log of Monitor Well
Geo p Engineers
Figure A47
MONITOR WELL NO. MW-16
WELL SCHEMATIC
3 r aDESCRIPTION
0 3 E G u
q 0 4
M 0 0) Symbol Surface Elevation(ft.): 19.54
Steel surface 0
monument and Refer to log of Boring B-16 for soil conditions encountered
concrete Water level at a depth of 7.15 feet on 1/4/91
Bentonite seal
2-inch Schedule 40
5— PVC solid pipe 5
10 — —10
2-inch Schedule 40
PVC screen,
0.020-inch slot
width
15 — -15
W
LU —Medium sand
backfill
z
H
0.
LLJ
20 Base of well at 20 20
feet
0)
Co 25 — —25
U
in
<1
30 — —30
_j
35 — 35
LD
CD - -
M
I
CD - -
0)
40 — —40
G Note:See Figure A-2 for explanation of symbols
�g4jtv. Log of Monitor Well
Geol%-o-o Engineers
Figure A48
GE 30-88
0120 -090-B02 NLT : KKT 12 -31 -90
U . S . STANDARD SIEVE SIZE
O °
�
100 O
90
\lV\=
so
w 7 0
rD
m 60
-
z 50
40
z
w
u 30
w
° 20
10
n 0
„ a 1000 100 10 1 . 0 0 . 1 0 . 01 0 . 001
-1 GRAIN SIZE IN MILLIMETERS
C O
m Z GRAVEL SAND
n COBBLES COARSE FINE COARSE MEDIUM FINE SILT OR CLAY
a
4;h rn EXPLORATION SAMPLE
N
SYMBOL NUMBER DEPTH SOIL DESCRIPTION
1 42 . 5 ' DARK GRAY FINE TO MEDIUM SAND WITH SILT,
A TRACE OF COARSE SAND, FINE GRAVEL AND
SHELL FRAGMENTS ( SP-SM)
5 22 . 5 ' BLACK FINE TO MEDIUM SAND WITH A TRACE
OF SILT ( Sp)
GE 30-88
0120-090-B02 NLT:KKT 1/3/90
U . S . STANDARD SIEVE SIZE
100
O
SIM 9 0
80 --
W 7 0
m 60
W 50
Z
LL
40
z
w
u 30
w --
20
i0
C)
>
0
'n D 1000 100 10 1 . 0 0 . 1 0 . 01 0 . 001
C GRAIN SIZE IN MILLIMETERS
7C =
R' COBBLES
a C COARSERA J.
FINE COARSE MEDIUM ND FINE SILT OR CLAY
N �
p < EXPLORATION SAMPLE
m SYMBOL NUMBER DEPTH SOIL DESCRIPTION
N
6 ? 0 ' GRAY FINE TO COARSE SAND WITH SILT AND
FINE GRAVEL AND A TRACE OF ORGANIC MATTE
(sw-SM)
19 5 GRAY SILTY FINE SAND WITH OCCASIONAL
MEDIUM SAND AND ORGANIC MATTER (SM )
4
0120-090-B02 NLT : KKT 1 ? -31 -90
60
PLASTICITY CHART
lU
i/ 50 CH
`VID
w 40
Z
H
3 0
U
OH and MH
in
20
CL O
> 10
m CL-ML �� ML and OL
70 �
W "
00 10 20 30 40 50 60 70 80 90 100
'n r LIQUID LIMIT
C �
m N EXPLORATION SAMPLE MOISTURE LIQUID PLASTICITY
I
m NUMBER DEPTH CONTENT (�) LIMIT (%) INDEX Cod SOIL DESCRIPTION
1 2 . 5 ' 45 43 15 GRAY SILT (ML)
C ® 10 7 . 5 ' 44 36 9 GRAY SILT WITH OCCASIONAL
r ORGANIC MATTER (ML)
N ® 18 53 ' 40 31.E 5 GRAY CLAY WITH OCCASIONAL
FINE SAND (CL)
PRESSURE (LBS/FT2 x 10 3)
0 .1 .2 .3 .4 .5 1 2 3 4 5 10 20 30 40 50
I
I I I I
I I I I I
02
I I I I I
p I I I I
I I I I I
. 04
= 1 I I
Ln
U
Z
w
_ . 06
U
Z I I 1 I I
o I I I I I
o 08
o
Ln
it ocli
I I I I I
I I I I I
10
1 I 1 I i
I I I I
z
I I I I I
CV
m 1 I I I I
o I I I I
CU
o SAMPLE DRY
cli
BORING DEPTH SOIL MOISTURE DENSITY
CZ) KEY NUMBER (FT) CLASSIFICATION CONTENT (LBS/FT3�
-� 10 7 . 5 GRAY SILT WITH 44% 77
OCCASIONAL ORGANIC
co
MATTER (ML)
CONSOLIDATION TEST RESULTS
Geol00Engineers FIGURE A-52
PRESSURE (LBS/FT2 x 103 )
0 .1 .2 .3 .4 .5 1 2 3 4 5 10 20 30 40 50
I
I I I I I
I
i I I I I
I I I I
04
I I I I I
I I I I
I I I I I
. 08
= I I I I I
U
Ln
w
12
Z I i I I I
o I I I I
0 18
J I I I I
0
Ln
I I I
I I I I i
20
I
J
z I I I I I
NCD
I I I I I
m I I I I I
0
o SAMPLE DRY
o BORING DEPTH SOIL MOISTURE DENSITY
c'\' KEY NUMBER (FT) CLASSIFICATION CONTENT (LBS/FT3)
0
c' 12 13 - BROWN ORGANIC SILT 101% 60
` WITH OCCASIONAL
ORGANIC MATTER (OL)
\� CONSOLIDATION TEST RESULTS
Geo�plooEngineers FIGURE A-53
PRESSURE (LBS/FT2 x 103)
.1 .2 .3 .4 .5 1 2 3 4 5 10 20 30 40 50
0 I
I I I I I I
I
I I I I I
I I I I I
. 04
I I I I
I I I I I
I I I I
08
i I I I I
U
Z
w I I I I I
_ . 12
CD
Z I I I I (
p I I I I I
Q 16
o
J I I I I
o I I I I I
20
'= I
CN
CD
CD
J
z
I I I I
I I I I i
n
I I I I I
I I I I I
0
N
o SAMPLE DRY
BORING DEPTH SOIL MOISTURE DENSITY
KEY NUMBER (FT) CLASSIFICATION CONTENT (LBS/FT3)
u 18 53 GRAY SILT WITH 40° 79
OCCASIONAL FINE SAND
00 (ML)
CONSOLIDATION TEST RESULTS
GeolrEngineers FIGURE A-54
80
60
v;
w 40
G �
O� F-
I to
M �
I G
cN w
V)
20
J \L
N 0 20 40 60 80 100
G
rn
o NORMAL STRESS, PST
m
G
N
BORING SAMPLE SAMPLE MOISTURE DRY
SYMBOL NUMBER DEPTH DESCRIPTION CONTENT DENSITY
(FEET) M (PCF)
1 42.5 DARK GRAY FINE TO MED 21 102
IIUM SAND WITH SILT(SP SM)
__ _ 5 22.5 BLACK FINE TO MEDIUM 22 103
� SAND WITH A TRACE OF
SILT (SP)
6 37 . 5 RAY FINE TO MEDIUM 13 118
co
SAND WITH SILT (SP-SM
H
w
C7
CONSOLIDATED DRAINED
Am TRIAXIAL TEST DATA
Geo WEEngineers FIGURE A-55
80
60
1
Lo
Iu
W
2
H
40
w /
rn /
2 0 \r-,
� 1
0
J
z 0 20 40 60 80 100 120
NORMAL STRESS, PSI
CV
O
co
I
cl SAMPLE MOISTURE DRY
BORING SAMPLE
CD
SYMBOL NUMBER DEPTH DESCRIPTION CONTENT DENSITY
(FEET) W (PCF)
N
0 19 28 BLACK FINE TO 21 104
MEDIUM SAND (SP)
� — — — 19 58 GRAY SILTY FINE 29 94
I SAND (SM)
Q�
-• 11 47 . 5 GRAY FINE TO MED- 18 109
IUM SAND WITH
w SILT AND SHELL
FRAGMENTS SP-SF1
top CONSOLIDATED DRAINED
�lTRIAXIAL TEST DATA
Geo Qm' Engineers
FIGURE A-56
APPENDIX B
A P P E N D I X B
�&PECIALTY CONSULTANTS GROUP, INC.
301 South Hamlin Drive Telephone (206) 435-3422
Arlington, Washington 98223 FAX: (206) 435-3580
Worldwide Consulting
December 28 , 1990 Project No . 5639128
Ms . Nancy Tochko
GeoEngineers , Inc.
2405 140th Avenue N.E.
Bellevue, Washington 98005
Reference: GeoEngineers Job No. 120-90
Boeing Longacres Park Project
Subject: Report on Soil Sample Corrosivity Testing
Dear Ms . Tochko:
This letter and the appended material constitute our report on the
testing carried out on 10 soil samples received from your office.
Purpose of Testing
In accordance with your instructions , the soil sample testing
consisted of measuring the resistivity, pH, Redox , and Sulfides
content to determine corrosion rates that could be anticipated for
buried metallic structures to be installed in the soils
represented by the samples .
Description of Testing
The results of the soil sample testing are recorded on the "Soil
Sample Testing Results" sheet included in the Appendix to this
report.
Information defining soil resistivity, pH, Redox, and Sulfides
content is also included in the Appendix for reference purposes .
Results of Testing
1 . The resistivity tests run on the 10 soil samples showed only
slight variation in the soils from boring location to boring
location, and with depth at the individual locations .
(a) The resistivities of the soils range from a low of 2 ,900
ohm-cm (mildly corrosive) to a high of 17 ,000 ohm-cm
(relatively non-corrosive) , with 9 out of the 10 samples
in the mildly corrosive range .
B - 1
Ms . Nancy Tochko
December 23, 1990
page -2- *PECIALTY CONSULTANTS GROUP, INC.
(b) The variations in resistivity from point to point will
tend to generate increased corrosion activity on metallic
structures installed in these soils , because of potential
differences associated with the varying resistivities .
2 . The pH testing carried out on the 10 soil samples showed all
to be in the acidic range (pH 5 .26 to pH 6 .39) .
(a) The acidic pH of the soils represented by the samples
will tend to increase general corrosion rates , albeit not
to a serious degree.
3 . The Redox and Sulfides testing conducted on the 10 soil
samples showed significant indications of sulfate reducing
bacteria activity.
(a) The Redox value of all 10 soil samples was well below
+100 millivolts , with seven of the 10 samples having
negative values .
(b) Three of the 10 samples showed " trace" Sulfides .
i
4 . The physical characteristics of the soils represented by the
10 samples tested consisted predominantly of low resistivity
dense silty clays which will tend to generate corrosion
activity on buried metallic structures .
Conclusions
From the testing accomplished on the 10 soil samples from the
Boeing Longacres Park Project site, the following is concluded
with respect to corrosion rates on metallic structures and piping
installed in these soils :
1 . It is estimated that general corrosion rages of up to three
mils per year ( .003" ) will occur on steel structures and on
steel and ductile iron utility piping installed in these
soils .
(a) Because of the variations in the soils from point to
point, and the conditions favorable to anaerobic
bacterial activity, it is estimated that pitting activity
up to six mils per year ( .006") could be experienced .
(b) Other factors could also increase corrosion and pitting
rates . These factors include stray current activity,
high concentrations of soil salts (chlorides , sulfates,
sulfides , etc. ) , and others .
B - 2
Ms . Nancy TochkO
December 28 , 1990
page -3- *PECIALTY CONSULTANTS GROUP, INC.
Recommendations
If corrosion rates are anticipated that could affect the integrity
and shorten the planned service life of buried metallic utility
piping and other metallic structures that will be installed in
these soils , the following should be considered .
1 . Coat steel piping and other steel structures with a good
quality protective coating such as a coal tar mastic,
protective tape wrap, or other such material .
(a) Supplement the protective coating with the installation
of sacrificial anodes to provide control of corrosion at
"holidays" and damaged areas in the coating .
2 . Ductile iron piping should be encased in loose polyethylene
wrap in accordance with ANSI/AWWA Standard C105/A21 .5-82 .
(a) A copy of this standard is appended to this report .
3 . Coated and/or wrapped steel and ductile iron piping should be
bedded and covered with clean washed sand .
4 . Concrete structures installed in the soils represented by the
10 samples tested should require no additional corrosion
protection , unless it is determined that excessive amounts of
soil salts are present that are deleterious to concrete .
(a) This would apply to concrete coated steel and ductile
iron piping .
(b) Soil salts deleterious to concrete include chlorides,
sulfates , carbonates , and others .
(c) Laboratory testing of a few soil samples from random
borings across the site should be tested for chlorides
and sulfates to determine whether or not deterioration
of concrete might occur .
B - 3
Ms . Nancy Tochko
December 28 , 1999
page -4- *PECIALTY CONSULTANTS GROUP, INC.
Thank you for the opportunity afforded us to be of service to you
on this project .
If you have any questions concerning this report; or if additional
information is needed , please contact us at once .
Respectfully submitted ,
H. F. (Hank) Galka
Sr . Corrosion Consultant
HFG//cv
Attachments
B - 4
SO I L. SAMPLE TEST I IyCC RESULTS
BORING RESISTIVITY REDOX
NUMBER DEPTH DESCRIPTION (ohm-cm) PH (mv) SULFIDES
1 Be Medium brown coarse 4 ,300 5 .47 +25 Negative
silty sand, clayey,
damp.
2 3 ' Yellow brown fine 4 ,600 5 .42 -49 Negative
silty sand, lumpy,
damp.
3 3 ' Yellow fine silty 2 ,900 5 .59 +12 Negative
clay, damp.
5 8 ' Dark gray medium fine 6 ,900 6 .39 -125 Trace
silty sand, wet .
6 8 ' Light brown fine silty 6 ,100 5.26 -11 Negative
sand, clay, damp
7 3 ' Dark brown/black 12,000 5.65 -2 Trace
medium coarse silty
sand, wet.
9 3' Meduim brown fine 7 ,600 5 .93 -11 Trace
silty sand, lumpy,
dry.
14 8 ' Dark brown medium 8 ,400 6.29 -42 Negative
fine silty sand , wet .
15 8 ' Light brown (tan) very 3 ,700 6.21 -3 Negative
fine sticky clay, wet .
19 8 ' Medium brown, medium 17 ,000 6.25 +3 Negative
fine silty sand, wet .
B - 5
SOIL RESISTIVITY
The corrosivity of a soil is directly related to its resis-
tivity. Soil resistivity tends to control and distribute
corrosion currents on buried metallic structures. For ex-
ample, the lower the soil resistivity , the better the soil
conducts electricity , and therefore, the greater the corro-
sion rate. Conversely, the higher the soil resistivity, the
less the ability of the soil to conduct electricity, and
therefore, the lower the corrosion rate.
The unit of soil resistivity measurement most widely used in
corrosion control work is the ohm-centimeter . The following
table shows the corrosivity of soils as related to their
resistivity .
Soil Resistivity Soil Corrosivity
---- ---------- ---- ----------
Below 500 ohm-cm Very corrosive
500 to 1000 ohm-cm Corrosive
1000 to 2000 ohm-cm Moderately corrosive
2000 to 10,000 ohm-cm Mildly corrosive
Above 10,000 ohm-cm Progressively less corrosive
Wet , heavy clays and tideflats muck are examples of low
resistivity soils which are usually very corrosive. Examples
of high resistivity soils are dry sands and gravels which are
usually relatively noncorrosive.
B - 6
SOIL pH
PH is the measurement of the hydrogen (H+) ion concentration
in a soil or solution . In water , when the pH is 7 (or
neutral ) , the hydroxyl (OH-) ions are in equal concentration
to the hydrogen ions at lx (E-07) moles/ liter . The log of the
reciprocal of this value is equal to 79 or therefore neutral .
At a pH of 6, the H+ ion concentration is 10 times greater
than the neutral state, and the solution is acidic . Con-
versely, when the pH is 8 the concentration of H+ ions is 10
times less than neutral , and the solution is basic or alka-
line.
Soils may be either acid , alkaline, or neutral . Acidic soils
tend to be more corrosive than alkaline soils for materials
such as steel , ductile iron, copper , and concrete; while the
more alkaline soils may adversely affect aluminum.
Soil pH, in combination with other factors, will affect the
corrosion rate of a buried metallic structure in various
ways. For example, at pH 0.0 to 6.5 (acidic range) , a soil
will serve as a very corrosive electrolyte when moisture is
present in sufficient amounts. At pH 6.5 to 7.5 (relatively
neutral range) , conditions are optimum for bacteriological
action, such as sulfate-reducing bacteria . At pH 7.5 to 14 .0
( alkaline range) , dissolved salts are generally present and
low soil resistivity is usually found .
B - 7
Similar to steel , cast iron and ductile iron are not readi-ly
attacked in environments ranging between pH 4 .0 and pH 8.5.
V
Below the pH 4 .0 range, the iron is increasingly oxidized .
Above the pH 0.5 range, the soils provide a good electrolyte
for development of anodic and cathodic differential cells
that cause extensive pitting . In the neutral pH range ( 6.5
to 7 .5) , anaerobic bacteria thrive in soils with low Redox
potential , organic food sources, and water present .
Steel in concrete cylinder pipelines is protected by the
hydration of the cement which results in the formation of
calcium hydroxide providing a uniform alkaline environment
with a pH between 12 and 13. Highly acidic soils , however ,
provide hungry hydrogen ions that break down this favorable
alkaline environment and form concentrations of chloride ions
that stimulate oxidation of the reinforcing steel . The
resulting force of the expansion of the corrosion products
causes spalling of the protective concrete coating and in-
creasing corrosion problems .
B - 8
RF_DO X TESTING
"Redo,:" is an abbreviation of the term "Oyidation-Reduction
Potential " . The measurement of Redox is an indication of the
amount of oxidents in a soil . A knowledge of soil Redox is
important since metals in a low oxidation environment are
anodic to those in a higher state. An ,increasing Redox
potential above 100 millivolts (mv) is an indication of
increasing sail aeration. Below that range, the life support
for sulfate reducing bacteria is enhanced and increases as
the Redox potential decreases. Where negative Redone poten-
tials are found , the growth of anaerobic sulfate reducing
bacteria is optimum, providing that other sail conditions are
favorable--such as neutral pH, water , and the presence of
sulfates. Soils containing stagnant water with much organic
material are likely to exhibit low Redox potential and indi-
cate conditions suitable for the growth of sulfate reducing
bacteria.
i
B - 9
SULFIDES TESTING
When sulfate reducing . bacteria consume sulfates present in
soil , the by-products of that process include sulfide com-
pounds. These compounds act as depolarizing agents that
enhance corrosion activity in localized cells on buried
metallic structures.
Anaerobic bacteria thrive best at soil temperatures above SO
degrees F and at a pH of 7.0. They became less active at
lower temperatures and as the pH departs from the neutral
range.
The presence of sulfides in a sail is determined by the
Sodium-Azide Iodine qualitative test . In this test , sulfides
in the soil sample act as a catalyst and release free
nitrogen from the compound mixtures with resultant bubbling
or foaming .
The results of this test are laced within three categories
P g
for reporting purposes: Negative, Trace, and Positive. These
categories reflect an increasing scale of reaction from
nothing to vigorous foaming or evolution of gas. The greater
the gas evolution, the higher the amounts of sulfides present
in the soil sample.
I
B - 10
ANSI/AWWA C105/A21.5-82 _
[Revision of ANSI./AWWA C105-72 (107)]
AM ER KM NATKONAL
STAN DAA
for
POLYETHYLENE ENCASEMENT FOR
DUCTILE-IRON PIPING FOR WATER AND OTHER
LIQUIDS
ADMINISTRATIVE SECRETARIAT
AMERICAN WATER WORKS ASSOCIATION
CO-SECRETARIATS
AMERICAN GAS ASSOCIATION
NEW ENGLAND WATER WORKS ASSOCIATION
First edition approvi l l,r Americart National Standards Institute, Inc.. Dec. 27, 1972.
Rey iced editicttt althru ed h r Anrerk nn A'atinrtal.Statidard.c l»stirtcte. lnr.. Alai•26. 1982.
Published by
AMERICAN WATER WORKS ASSOCIATION
6666 West Quincy Avenue, Denver, Colorado 80235
B - 11
i
American National Standard
An American National Standard implies a consensus of those substantially concerned
with its scope and provisions._An American National Standard is intended as a guide to
aid the manufacturer, the consumer, and the general public. The existence of an
American National Standard does not in any respect preclude anyone, whether he has
approved the standard or not, from manufacturing, marketing, purchasing, or using
products, processes, or procedures not conforming to the standard. American National
Standards are subject to periodic review, and users are cautioned to obtain the latest
editions. Producers of goods made in conformity with an American National Standard
are encouraged to state on their own responsibility in advertising and promotion
material or on tags or labels that the goods are produced in conformity with particular
American National Standards.
CAUTION NOTICE. This American National Standard may be revised or
withdrawn at any time. The procedures of the American National Standards Institute
require that action be taken to reaffirm, revise, or withdraw this standard no later than
Five(5) years from the date of publication. Purchasers of American National Standards
may receive current information on all standards by calling or writing the American
National Standards Institute, 1430 Broadway, New York, N.Y. 100I8,(212)354-3300.
Copyright 0 1982 by American Water Works Association
Printed in USA
ii
B — 12
Committee Personnel
Subcommittee 4, Cast-Iron Pipc and Fittings, which reviewed this standard,had the
following personnel at that time:
TROY F. STROUD, Chairman
KENNETH W. HENDERSON, Vice-Chairman
User Members Producer Members
S. C. BAKER A. M. HORTON
B. W. FRANKLIN J. P. JOHNSON
K. W. HENDERSON HAROLD KENNEDY JR.
R. C. HOLMAN J. H. MILLER
M. G. HOOVER J. H. SALE
D. A. LINCOLN T. F. STROUD
W. H. SMITH T. B. WRIGHT
Standards Committee A21, Cast-Iron Pipe and Fittings, which reviewed and
approved this standard, had the following personnel at the time of approval:
ARNOLD M. TINKEY, Chairman
THOMAs D. HOLMES, Vice-Chairman
JOHN 1. CAPITO, Secretary
Name of
Organization Represented Representative
American Gas Association H. J. FORK
American Society for Testing and Materials GEORGE LUCIw*
American Water Works Association G. S. ALLEN
R. A. ARTHUR
D. R. BOYD
J. L CAPITO*
K. W. HENDERSON
*Nonvoting liaison
B — 13 ���
Committee Personnel (continued)
American Water Works Association M. G. HOOVER
R. J. KOCOL
G. M. KRALIK
D. M. KUKUK
R. L. LEE
J. H. MILLER
W. H. SMITH
A. M. TINKEY
D. L. T►PPIN
THURMAN UPCHURCH
L. W. WELLER
Canadian Standards Association W. F. SEMENCHUK*
Ductile Iron Pipe Research Association T. D. HOLMES
HAROLD KENNEDY JR.
P. I. MCGRATH JR.
L. L. NEEPER
T. F. STROUD
4 Manufacturers' Standardization Society of the
Valve and Fittings Industry T. C. JESTER
Naval Facilities Engineering Command S. C. BAKER
New England Water Works Association ALBERT HELT
Underwriters' Laboratories, Inc. W. CAREYt
L. J. DOSEDLO
'Nonvoting liaison
II 1Alternate
I
1
B - 1 4 IV
Table of Contents
F.C. PACE src. rncr
Foreword 5-4 Installation. . . . . . . . . . . . . . . . . . . . .. . 2
1. History of Standard . . . . . . . . . . .. .. . %ri Table
11. History of Polyethylene Encasement vi5. . . . . . . . . . . . . ..I Tube and Shrct Sizes
111. Research . . . . .. . . . .. . . . . . . . . . . . . . vii `
IV. Useful Life of Polyethylene .. . . . . . .. vii Figures
V. Exposure to Sunlight . . . . . . . . . . . . .. vii
V1. Options . . .. .. . .. .. . . . . . . . . . .. . .. vii 5.1 Method A . . . . . . . . . . . . ... . . . . . . .. . 3
VI1. Major Revisions vii 5.2 Method B . . . . . . . . . . . . . . . . . . . . ... 3
5.3 Method C . . . . . . . . . . . . . . . . . . . . .. . 3
Standard
Appendix A .. . . . . . . . . . . . . . . . . . . . . . . . . 5
5-1 Scope . . . . . . . . . . . .. . . . . . . . . . . . . . . I Appendix Table
5-2 Definition. . .. . . . .. . . . . . .•. . . . . . . . . 1
5-3 Materials . . . . . . . . .. . . . . . .. . . . . . .. I A.I Soil-Test Evaluation . . . . . . . . . . . . .. . 7
I
v
B — 15
i
Foreword j
This foreword is for information onh, and is not apart of ANS1/A WWA C105.
I. History of Standard when required, for gray and ductile cast-
In 1926, ASA (now ANSI) Committee iron pipe and fittings.
A21, Cast-Iron Pipe and Fittings, was 2. Development of procedures for
organized under the sponsorship of the investigation of soil to determine
AGA, ASTM, AWWA, and NEWWA. when polyethylene protection is indi-
The current sponsors are AGA, AWWA, cated.
and NEWWA, and the present scope of In response to these assignments, Sub-
Committee A21 activity is standard)a- committee 4 has:
tion of specifications for cast-iron and I . Developed ANSI A21 .5-1972
ductile-iron pressure pipe for gas, water, (AWWA C105-72), Standard for Poly-
and other liquids, and fittings for use with ethylene Encasement for Gray and Duc-
such pipe. These specifications are to tile Cast-Iron Piping for Water and Other
include design, dimensions, materials, Liquids.
coatings, linings, joints, accessories, and 2. Developed Appendix A outlining
methods of inspection and test. soil-investigation procedures.
In 1958, Committee A21 was reorgan- In 1976, Subcommittee 4 reviewed the
ized. Subcommittees were established to 1972 edition and submitted a recommen-
study each group of standards in accor- dation to Committee A21 that the stand-
dance with the review and revision policy and be reaffirmed without change from
of ASA (now ANSI). The present scope the 1972 edition, except for the updating
of Subcommittee 4, Coatings and Lin- of this foreword.
ings, is to review the matter of interior In 1981 , Subcommittee 4 again
and exterior corrosion of gray and reviewed the standard. The major revi-
ductile-iron pipe and fittings and to draft sions incorporated into the current edi-
standards for the interior and exterior tion as a result of that review are listed in
protection of gray and ductile-iron pipe Sec. VII of this foreword.
_ and fittings.
In accordance with this scope, Sub- II. History of Polyethylene Encase-
committcc 4 waschargcd with the respon- ment
sibility for: Loose polyethylene encasement was
1. Development of standards on first used experimentally in the United
polyethylene encasement materials and States for protection of cast-iron pipe in
their installation as corrosion protection, corrosive environments in 1951. The first
V1
B — 16
PO I.YETIIYLENE- I:NCASI'MI NT FOR DUCT II.I.-IRON PIPING Vii
field installation of polyethylene wrap on tion of the US Department cif the
cast-iron pipe in an operating water sys- Intcriort on polyethylene film used
tem was in 1958 and consisted of about underground showed that tensile strength
600 ft (180 m) of 12-in. pipe installed in a was nearly constant in a 7-yr test period
waste-dump fill area. Since that time, and that elongation was only slightly
hundreds of installations have been made affected. The Bureau's accelerated soil-
in severely corrosive soils throughout the burial testing (acceleration estimated to
United States in pipe sizes ranging from be five to ten times that of field condi-
4-54 in. in diameter. Polyethylene cncasc- tions) showed polvcthylcne to be highly
ment has been used as'a soil-corrosion resistant to bacteriological deterioration.
preventative in Canada, England, France. V. Exposure to Sunlight
Germany, and several other countries
since development of the procedure in the Prolonged exposure to sunlight will
United States. eventually deteriorate polyethylene film.
Therefore, such exposure prior to back-
III. Research filling the wrapped pipe should be kept to
Research by the Cast Iron Pipe a minimum. If several weeks of exposure
Research Association (CIPRA)* on sev- prior to backfilling are anticipated. Class
eral severely corrosive test sites has indi- C material should be used (see Sec. 5-
cated that polyethylene encasement 3.1.1).
provides a high degree of protection and
results in minimal and generally insignifi-
cant VI. Options
cant exterior surface corrosion of gray This standard includes certain options,
and ductile cast-iron pipe thus protected. which, if desired, must be specified.These
Investigations of many field installa- options are:
tions in which loose polyethylene encase- I . Color of polyethylene material
ment has been used as protection for gray (Sec. 5-3).
and ductile cast-iron pipe against soil cor- 2. Installation method—A, B, or C
rosion have confirmed CIPRA's findings (Sec. 5-4)—il there is a preference.
with the experimental specimens. These
field installations have further indicated VII. Major Revisions
that the dielectric capability of polycthyl- The major revisions in this edition con-
ene provides shielding for gray and duc- sist of the following:
tile cast-iron pipe against stray direct I. Reference to gray cast-iron pipe in
current at most levels encountered in the the title and throughout the standard was
field. deleted because gray iron pipe is no
IV, Useful Life of Polyethylene
longer produced in the United States.
2. Metric conversions of all dimen-
Tests on polyethylene used in the pro- sions are included in this standard. Metric
tection of gray and ductile cast-iron pipe dimensions are direct conversions of cus-
have shown that after 20 years of expo- tomary US inch-pound units and are not
sure to severely corrosive soils, strength those specified in International Organiza-
lossand elongation reduction are insignif- tion for Standardl7,ition(ISO) standards.
icant. Studies by the Bureau of Reclama-
tl.ahoratory and Field Investigations of Plastic
'CII'RA became the Ductile Iron Pipc Research Films. US Dept. of the Interior,Bureau of Reclama-
Association in 1979. tion, Rept. No. ChE-82 (Sept. 1968).
B — 17
ANSI/AWWA C105/A21.5-82
[Revision of ANSI/AWWA C105-72 (R77)]
American National Standard for
Polyethylene Encasement for
Ductile-Iron Piping for Water and Other Liquids
Sec. 5-1 Scope 5-3.1.1 Raw material used to manu-
This standard covers materials and facture Polvetht,lene film.
installation procedures for polyethylene Type: I
encasement to be applied to underground Class: A (natural color) or C (black)
installations of ductile-iron pipe. This Grade: E-1
standard also may be used for polyethyl- Flow rate (formerly melt index):
ene encasement of fittings, valves, and 0.4 maximum
other appurtenances to ductile-iron pipe Dielectric strength: Volume resistivity,
systems. minimum ohm-cm3 = I015
5-3.1.2 Pol reth riene film.
Sec. 5-2 Definition Tensile strength: 1200 psi (8.3 MPa)
5-2. 1 Polvethvlene encasement: minimum
The encasement of piping with polyethyl- Elongation: 300 percent minimum
ene film in tube or sheet form. Dielectric strength: 800 V/mil (31 .5
Sec. 5-3 Materials V/um) thickness minimum
5-3.2 77rickrress. Polyethylene film
5-3. I Po/rethv/ene. Polyethylene shall have a minimum thickness of 0.008
Film shall be manufactured of virgin in. (8 mil, or 200 µm). The minus toler-
polvethylene material conforming to the ante on thickress shall not exceed 10 per-
following requirements of ASTM Stand- cent of the nominal thickness.
and Specification D-1248-78—Polyethvl- 5-3.3 Tube size or sheet width.
ene Plastics Molding and Extrusion Tube size or sheet width for each pipe
Materials: diameter shrill be as listed in Table 5.1.
B - 18
2 ANSI!AWWA C105iA21.5-82
TABLE 5.1
Tube and Sheet Sizes
Minimum Polyethylene Width
Nominal Pipe in. (cm)
Diameter
in. Flat Tube Sheet
3 14 (35) 28 (70)
4 16 (41) 32 (82)
6 20 (51) 40 (102)
8 24 (61) 48 (122)
10 27 (69) 54 (137)
12 30 (76) 60 (152)
14 34 (86) 68 (172)
16 37 (94) 74 (188)
18 41 (104) 82 (209)
20 45 (114) 90 (229)
24 54 (137) 108 (274)
30 67 (170) 134 (340)
36 81 (206) 162 (411)
42 95 (241) 190 (483)
48 108 (274) 216 (549)
54 121 (307) 242 (615)
Sec. 5-4 Installation fashion lengthwise until it clears the pipe
5-4.1 General. The polyethylene ends.
encasement shall prevent contact between Lower the pipe into the trench and
the pipe and the surrounding backfill and make up the pipe joint with the preceding
bedding material but is not intended to be section of pipe. A shallow bell hole must
a completely airtight and watertight be made at joints to facilitate installation
enclosure. Overlaps shall be secured by of the polyethylene tube.
the use of adhesive tape, plastic string, or After assembling the pipe joint, make
any other material capable of holding the the overlap of the polyethylene tube. Pull
polyethylene encasement in place until the bunched polyethylene from the
backfilling operations are completed. preceding length of pipe, slip it over the
54.2 Pipe. This standard includes end of the new length of pipe, and secure
three different methods of installation of it in place. Then slip the end of the
polyethylene encasement on pipe. Meth- polyethylene from the new pipe section
ods A and B are for use with polvethylene over the end of the first wrap until it
tubes and method C is for use with overlaps the joint at the end of the preced-
polyethylene sheets. ing length of pipe. Secure the overlap in
5-4.2.1 Method A. (Refer to Figure place. Take up the slack width to make a
5.1.) Cut polyethylene tube to a length snug, but not tight, fit along the barrel of
approximately 2 ft (0.6 m) longer than the pipe, securing the fold at quarter
that of the pipe section. Slip the tube points.
around the pipe, centering it to provide a Repair any rips, punctures, or other
I-ft (0.3-m) overlap on each adjacent pipe damage to the polyethylene with adhesive
section, and bunching it accordion- tape or with a short length of polyethyl-
B — 19
F'OI.YI:I IIYI.FNF FNCASI:MI:NT FOR DUC1II.E-IRON PIPING 3
ene tube cut open, wrapped around the 3-ft (0.9-m) length of'polyethvlcne over
pipe, and secured in place. Proceed with the joint, overlapping the polyethylene
installation of the next section of pipe in previously installed on each adjacent sec-
the same manner. tion of pipe by at least I ft (0.3 m); make
5-4.2.2 Method B. (Refer to Figure snug and secure each end as described in
5.2.) Cut polyethylene tube to a length Sec. 5-4.2.1.
approximately I ft (0.3 m) shorter than Repair any rips, punctures, or other
that of the pipe section. Slip the tube damage to the polyethylene as described
around the pipe, centering it to provide 6 in Sec. 5-4.2.1. Proceed with installation
in. (15 cm) of bare pipe at each end. Make of the next section of pipe in the.same
polyethylene snug, but not tight; secure manner.
ends as described in Sec. 5-4.2.1. 5-4.2.3 Method C. (Refer to Figure
Before making up a joint, slip a 3-ft 5.3.) Cut polyethylene sheet to a length
(0.9-m) length of polyethylene tube over approximately 2 ft (0.6 m) longer than
the end of the preceding pipe section, that of the pipe section. Center the cut
bunching it accordion-fashion length- length to provide a l-ft(0.3-m)overlap on
wise. After completing tfie joint, putt the each adjacent pipe section, bunching it
I
Figure 5.1. Method A: One length of polyethylene tube for each length of pipe,
overlapped at joint.
-- -------- ---
N,
I
Figure 5.2. Method B: Separate pieces of polyethylene tube for barrel of pipe and
for joints. Tube over joints overlaps tube encasing barrel.
i
x
ti
l
Figure 5.3. Method C: Pipeline completely wrapped with flat polyethylene sheet.
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4 ANSI/AWWA C105/A21.5-92
until it clears the pipe ends. Wrap the polyethylene securely in place at valve-
polyethylene around the pipe so that it stem and other penetrations.
circumferentially overlaps the top quad- 5-4.5 Openings in encasement. Pro-
rant of the pipe. Secure the cut edge of vide openings for branches, service taps,
polyethylene sheet at intervals of approxi- blow-offs, air valves, and similar appurte-
mately 3 ft (0.9 m). nances 'oy making an X-shaped cut in the
Lower the wrapped pipe into the trench polyethylene and temporarily folding
and make up the pipe joint with the hack the film. After the appurtenance is
preceding section of pipe. A shallow bell installed, tape the slack securely to the
hole must be made at joints to facilitate appurtenance and repair the cut, as well
installation of the polyethylene. After as any other damaged areas in the
completing the joint, make the overlap as polyethylene, with tape.
described in Sec. 5-4.2.1.
Repair any rips, punctures, or other 5-4.6 Junctions between wrapped
damage to the polvethylene as described and univrapped pipe. Where polyethyl-
in Sec. 5-4.2.1. Proceed with installation ene-wrapped pipe joins an adjacent pipe
of the next section of pipe in the same that is not wrapped, extend the polyethyl-
manner. ene wrap to cover the adjacent pipe for a
5-4.3 Pipe-shaped appurtenances. distance of at least 2 ft (0.6 m). Secure the
Cover bends, reducers, offsets, and end with circumferential turns of tape.
other pipe-shaped appurtenances with 5-4.7 Back fill for pol"veth_t�lene-
polyethylene in the same manner as the wrapped pipe. Use the same backfill
pipe. material as that specified for pipe without
5-4.4 Odd-shaped appurtenances. polyethylene wrapping,exercising care to
When valves, tees, crosses, and other prevent damage to the polyethylene wrap-
odd-shaped pieces cannot be wrapped ping when placing backfill. Backfill mate-
' practically in a tube,wrap with a flat sheet rial shall be free from cinders, refuse,
or split length of polyethylene tube by boulders, rocks, stones, or other material
passing the sheet under the appurtenance that could damage polyethylene. In gen-
and bringing -it up around the body. eral. backfilling practice should be in
Make seams by bringing the edges accordance with the latest revision of
together, folding over twice, and taping AWWA C600, Standard for Installation
' down. Handle width and overlaps at of Ductile-Iron Water Mains and Their
( joints as described in Sec. 5-4.2.1. Tape Appurtenances.
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