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HEPWORTH - PAWLAK CEOTECHN1CAL
Hepworth.-Pawlak Geotechnical,1nc.
5020 County Road 154
Glenwood Springs, Colorado 81601
Phone: 970.945-7988
Fax: 970-945-8454
email: hpgeo@hpgeorech.com
PRELIMINARY GEOTECHNICAL STUDY
PROPOSED SPRINGRIDGE PLACE PHASE II
COUNTY ROAD 125
GARFIELD COUNTY, COLORADO
JOB NO. 101 126
JUNE 22, 2004
PREPARED FOR:
THE GREENWALD CHILDREN'S TRUST
CIO GLENWOOD BROKERS, LTD.
ATTN: PAT FITZGERALD
P.O. BOX 1330
GLENWOOD SPRINGS, COLORADO 81602
Parker 303-841-7119 • Colorado Springs 719-633-5562 • Silverthorne 970.468-1989
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY - 1 -
PROPOSED CONSTRUCTION - 1 -
SITE CONDITIONS - 2 -
GEOLOGIC CONDITIONS - 2 -
FORMATION ROCK - 3 -
SURFICIAL SOILS - 4 -.
SUBSURFACE EXPLORATION - 4 -
SUBSURFACE CONDITIONS - 5 -
GEOLOGIC SITE ASSESSMENT - 5 -
ROCKFALL -5-
STREAM FLOODING - 6 -
ALLUVIAL FAN FLOODING - 6 -
MOISTURE SENSITIVE SOILS - 7 -
CONSTRUCTION RELATED SLOPE INSTABILITY - 7 -
REGIONAL EVAPORITE DEFORMATIONS - 7 -
EARTHQUAKE CONSIDERATIONS - a -
RADIATION POTENTIAL - 8 -
ENGINEERING ANALYSIS - S -
PRELIMINARY DESIGN RECOMMENDATIONS - 9 -
FOUNDATIONS - 9 -
FLOOR SLAB - 9 -
BELOW GRADE CONSTRUCTION - 10 -
ROADWAY GRADING -10 -
SURFACE DRAINAGE -10 -
WATER TANK SITE -11 -
LIMITATIONS - I 1 -
REFERENCES -13 -
FIGURE 1- VICINITY MAP
FIGURE 2 -PRELIMINARY GEOLOGY MAP AND EXPLORATORY PIT LOCATIONS
FIGURE 3 - LOGS OF EXPLORATORY PITS
FIGURES 4 - 6 - SWELL -CONSOLIDATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
PURPOSE AND SCOPE OF STUDY
This report presents the results of a preliminary geotechnical study for the proposed
Springridge Place Phase II to be located along County Road 125, about five miles south
of Glenwood Springs, Garfield County, Colorado. The project site is shown on Figures 1
and 2. The purpose of the study was to evaluate potential geologic hazard impacts, and to
develop recommendations for preliminary design cite building foundation and site
grading. The study was conducted in accordance with our agreement for professional
engineering services to The Greenwald Children's Trust, dated April 6, 1994 and
subsequent proposal to Glenwood Brokers, Ltd. dated May 28, 2004. This report is an
update of our previous study for the proposed development (Hepworth - Pawlak
Geoteclmical, 2001).
A field exploration program consisting of a geologic reconnaissance and exploratory pits
was conducted to obtain information on the site and subsurface conditions. Samples
obtained during the field exploration were tested in the laboratory to determine their
compressibility, classification and other engineering characteristics. The results of the
field exploration and laboratory testing were analyzed to develop recommendations for
planning and preliminary design for building foundation and site grading. This report
summarizes the data obtained during this study and presents our conclusions,
recommendations and other geotechnical engineering considerations based on the
proposed development and the subsurface conditions encountered.
PROPOSED CONSTRUCTION
Development plans for the Phase lI part of the property consist of 81 single family
residential lots having sizes between about 1 acre to greater than 4 acres. Six of the lots
will be located uphill of County Road 125 and the rest of the lots will be located in the
valley bottom to eastern valley side. All of the building areas will be on slopes less than
40%. A private roadway system will provide access to the east of County Road 125. The
development plan is shown on Figure 2. Water and sewer services will be from central
Job No. 101 126
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systems. The roadway grading is assumed to be minor with cuts and fills up to about 10
feet deep. The Atkinson Ditch will be piped through the development.
SITE CONDITIONS
The development is situated on. an upland surface adjacent to the east flank of the Grand
Hogback, a large northwest trending ridge. The elevations vary from about 6400 feet at
the north end to 7200 feet on top of the ridge at the southwest boundary. Building sites
only extend to about elevation 6,550 feet on the east flank of the hogback (west side of
the development). Two smaller hogbacks occur to the east. A few bedrock outcrops
occur on the hogbacks. An ephemeral stream drains toward the north. A tributary joins
the main drainage near the center of the site. Arroyo cutting is occurring at the south end
of these drainages. Several irrigation ditches are located on the development. The central
portion of the site is mostly a fairly flat valley floor. The south, west and east sides have
steep slopes.
County Road 125 runs through the development from northwest to southeast, paralleling
the lower slope of the Grand Hogback. A ranch house and out buildings are located near
the center of the development. The existing development is located to the north. The
valley bottoms have been used for hay and pasture. Some trash was noted adjacent to the
east drainage at one location. Otherwise, the development area is typically natural.
Vegetation on the slopes consisted of sage, pinon, juniper and other brush. The valley
bottoms have grass and sage. An existing above ground, steel water tank is located west
of Lot 6.
GEOLOGIC CONDITIONS
The project site is located on the limb of the Grand Hogback monocline. This first order
regional structure defines the boundary between the Pieance basin that lies to the west and
the Carbondale evaporite collapse center that lies to the east (Kirkham and Widmann,
1997). The rnonocline was formed during the Laramide progeny about 40 to 70 million
Job No. 101 126
Gtech
-3 -
years ago as a result of regional compressional stresses. The sedimentary rocks on the
monocline limb in the project area have an average strike of about N 300 W. The average
dip of the monocline limb in this area is about 45° to the southwest, but dips in the project
area vary from 90 to 78° because of secondary folding (Kirkham and Others, 1996).
Locally the bedding is overturned and the bedding dips are as much as 28° to the
northeast in the eastern part of the project area. Faults have not been mapped at the
project site, but regional mapping has identified several northwest trending, down to the
southwest normal faults to the west of the project area (Kirkham and Others, 1996).
These faults appear to be bedding plane faults in the Mancos Shale and Mesa Verde
Group that result from shallow crustal strains associated with evaporite solution and flow
in the Carbondale evaporite collapse center. The faults displace and form scarps in
Pleistocene and possibly Holocene age debris flow deposits (Kirkham and Others, 1996).
This indicates that some of the faults may have movements that are younger than 10,000
years.
FORMATION ROCK
Formation rock at the project site includes the Cretaceous Dakota Sandstone (Kd), the
Jurassic Morrison Formation (Jm) and Entrada Sandstone (Te), the Triassic and Permian
Chinle and State Bridge Formations (TRPcs) and the Permian and Pennsylvanian Maroon
Formation (PPm), see Figure 2. The project site is located in a strike valley between two
hogback ridges. The resistant Entrada Sandstone forms the crest of the hogback along the
western side of the project area and resistant beds in the Maroon Formation forms the
hogback along the eastern side of the project area. All of the proposed development will
be in areas underlain by the Maroon Formation. The Maroon Formation is made up of
red interbedded sandstone, siltstone, mudstone and shale with some minor, thin gray
limestone beds. The rock is usually hard and cemented. The rock mass is cut by joints
that parallel the bedding and at high angles to the bedding.
Job Aro. 101 126
4
SURFICIAL SOILS
Formation rock in the project area is usually covered by surficial soils. Relatively
shallow colluvium (Qc) and local rock outcrops are present on the boundary hogbacks
and upland ridges on the valley floor. Small alluvial fans (Qat) have developed at the
mouths of several ephemeral drainages on the eastern hogback. Alluvial aprons (Qaa)
have developed along the lower part of the western hogback and lower slopes of the
upland ridges on the valley floor. The relatively flat valley floor at the project site is
underlain by alluvium (Qal) that grades to a•low terrace level along Four Mile Creek to
the north of the project area. This terrace lies about 10 to 20 feet above the modern creek
chatlnel and most of the valley floor alluvium in the project area was probably deposited
during the late Pleistocene.
The exploratory pits show that the surficial soils at the project site are typically sandy
clay and silty sand with angular rock fragments from gravel- to boulder -size. Formation
rock was less that five feet deep in several of the pits located on the lower parts of the
boundary hogbacks and upland ridges on the valley floor.
SUBSURFACE EXPLORATION
The subsurface exploration for the project was conducted on April 13, 22 and 29, 1994.
Eleven exploratory pits were excavated at the approximate locations shown on Figure 2 to
evaluate the subsurface conditions. The pits were dug with a rubber tired backhoe and
logged by a representative of Hepworth-Pawlak Geotechnical, Inc.
Samples of the subsoils were taken with relatively undisturbed and disturbed sampling
methods. Depths at which the samples were taken are shown on the Logs of Exploratory
Pits, Figure 3. The samples were returned to our laboratory for review by the project
engineer and testing.
Job No. I01 126
sated"
-5 -
SUBSURFACE CONDITIONS
Graphic Togs of the subsurface conditions encountered at the site are shown on Figure 3.
The subsoils encountered in the valley bottom areas consist of about 1 to 1 'fz feet of
topsoil above sandy silty clay and silty sand with rock fragments. On the valley side
slope areas, sandstone bedrock was encountered. between depths of 1/2 to 6 feet below
rocky, silty sand and clay colluvial soils. The bedrock is generally hard to very hard and
could not be effectively dug with the backhoe. The soil moisture was relatively low and
no free water was encountered to the pit depths of 8 to 11 feet. The central field area was
being flood irrigated at the time of our April 29, 1994 site visit.
Laboratory testing performed on samples obtained from the pits included natural moisture
content and density, gradation analyses, and Liquid and plastic limits. Results of
consolidation testing performed on relatively undisturbed liner samples of the sandy clay
and silt soils, presented on Figures 4, 5 and 6, indicate Low compressibility under initial
low moisture conditions and moderate to high compressibility when wetted and loaded.
The samples generally showed a low to moderate collapse potential. The liquid and
plastic limits testing indicates the soils are generally low plasticity. The laboratory testing
is summarized in Table 1.
GEOLOGIC SITE ASSESSMENT
There are several conditions of a geologic nature that should be considered in project
planning and design. These conditions and their expect influence on the proposed
development are discussed below.
ROCKFALL
In some places outcrops of Entrada Sandstone along the western hogback crest are
potential start areas for rockfall that could potentially reach building sites on Lots 1
Jab No. 1 U1 126
Gate
-6 -
through 5. The presence of a potential rockfall start zone on the eastern hogback in the
vicinity of Lots 63 through 81 was field reviewed for the current study update and found
to not be a potential impact to the lots.
An analysis should be conducted to assess the potential rockfall risks to Lots 1-5. The
potential risk of rockfall to the building envelopes on Lots 1-5 appears low, but if the
analysis shows that the rockfall risk is unacceptable, then mitigation should be
considered. Mitigation could consist of removing unstable rock blocks before
development, outcrop stabilization, rockfall catching structures, or a combination of these
methods. The potential rockfall start area that could potentially impact Lots 1 through 5 is
not located on. the property. Outcrop mitigation in this area would require the cooperation
of the adjacent land owner.
STREAM FLOODING
Small ephemeral stream channels are locally present in the valley floor alluvium (Qa I)
and alluvial aprons (Qaa) in the proposed development areas. A civil engineer
specializing in hydrology should evaluate the flood potential along these drainages as part
of the overall storm water management plan for the development. Channel improvements
and drainage easements may be needed in some areas.
ALLUVIAL FAN FLOODING
The small alluvial fans in the eastern part of the project area are potential sites of
occasional thunderstorm related, high sediment concentration flash flooding. Lots that
may be impacted by this condition are Lots 63 though 72 and Lot 81. A civil engineer
specializing in hydrology should evaluate the potential flash flood routing on the alluvial
fans as part of the overall storm water management plan for the development. Channel
improvements, drainage easements, and deflection berms may be needed in some areas.
Job No. 101 126
G4Stech
MOISTURE SENSITIVE SOILS
Our experience in the area and the laboratory tests show that some of the surficial soils in
the project area are moisture sensitive. These soils have a moderate to high
compressibility when wetted and loaded. Preliminary recommendations for foundations
on moisture sensitive soils are presented in the Preliminary Design Recommendations
section of this, report.
CONSTRUCTION RELATED SLOPE INSTABILITY
We do not expect unusual problems with construction related slope instability if the
proposed grading is engineered and extensive cuts and fill are not needed. Grading on the
steeper slopes may require retaining walls and slope reinforcement to Iimit the extent .of
slope disturbance. Grading plans for roads, building sites and other facilities should be
evaluated by a geotechnical engineer on a site specific basis. These evaluations should
consider potentially adverse bedding in deep cuts in formation rock. Preliminary
recommendations for roadway grading are presented in the Preliminary Design
Recommendations section of this report.
REGIONAL EVAPORITE DEFORMATIONS
The faults to the west of the project area and other features in the Carbondale evaporite
collapse center to the east of the project area are associated with regional ground
deformations related to evaporite solution and flowage. Some of this deformation may be
younger than 10,000 years, but it is uncertain if the deformations are still active or if they
have stopped. If ground deformations are still occurring their rates are low and would be
occurring over broad areas. Because of this the risk of potential problems to residential
buildings is viewed to be Iow. We are not aware of problems associated with possible
regional evaporite deformations in the project area.
Job No. 101 126
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EARTHQUAKE CONSIDERATIONS
The project area could experience moderately strong earthquake related ground shaking.
Modified Mercalli Intensity VI ground shaking should be expected during a reasonable
service life for the development, but the probability for stronger ground shaking is low.
Intensity VI ground shaking is felt by most people and causes general alarm, but results in
negligible damage to structures of good design and construction. Occupied structures
should be designed to withstand moderately strong ground shaking with little or no
damage and not to collapse under stronger ground shaking. Considering the nature of the
faults to the west of the project area, in our opinion, these faults although geologically
young do not increase the earthquake potential at the project site. The region is in the
1997 Uniform Building Code, Seismic Risk Zone 1. Based on our current understanding
of the earthquake hazard in this part of Colorado, we see no reason to increase the
commonly accepted seismic risk zone for the area.
RADIATION POTENTIAL
The project site is not located in an area where geologic deposits are expected to have
unusually high concentrations of radioactive minerals. However, there is a potential that
radon gas could be present in the area. It is difficult to assess the potential for future
radon gas concentrations in buildings before the buildings are constructed. Testing for
radon gas can be done when the residences and other occupied structures have been
completed. New building are often designed with provisions for ventilation of lower
enclosed spaces should post construction testing show unacceptable radon gas
concentrations.
ENGINEERING ANALYSIS
The subsurface conditions encountered throughout the project area are variable but should
be suitable for support of spread footing foundations. The colluvium in the steeper slope
areas and the fine-grained soils in the non- irrigated valley bottom areas tend to be
Job No. 101 126
-9-
hydrocoinpressive. We expect that the soils in the historically irrigated fields have been
wetted and should be less prone to hydrocompression. The bedrock will provide
excellent support for buildings. Groundwater was not encountered and basement level
construction appears feasible in most areas of the property. The bedrock is very hard and
may limit the practical use of basements, especially where the rock is cemented and
requires blasting t� dig. The soils and bedrock should be suitable for typical roadway
grading with the expected relatively minor cut and fill sections.
PRELIMINARY DESIGN RECOMMENDATIONS
Development of the property should be feasible based on geotechnical considerations.
The following recommendations are made for planninggand preliminary design of the
buildings and site grading.
FOUNDATIONS
Spread footings placed on the natural soils below the topsoil should be suitable for
support of typical light residential building loads. Allowable soil bearing pressures in the
range of 1,000 psf to 2,000 psf should be acceptable. The hydrocompression potential
can probably be mitigated by engineered foundation design and should be evaluated on a
site specific basis. Compaction of the subgrade can help reduce the settlement potential.
Footings placed on the bedrock materials should have allowable bearing pressures in the
range of 3,000 psf to 6,000 psf. Additional subsurface exploration should be performed
by the individual lot owner when the building location, grading and loading conditions
have been determined to provide the site specific bearing recommendations.
FLOOR SLAB
The natural soils below the topsoil should be suitable for support of lightly loaded slabs -
on -grade. The upper soils may be compressible and result in some slab movement.
Removal and reconzpaction can reduce the potential for movement. Separating the slab
Job M. 101 126
Gterta•ch
- 10 -
from the bearing walls and columns is usually adequate to allow for slight movement and
limit potential distress. Backfill placed beneath slabs should consist of properly placed
and compacted soil excluding vegetation, topsoil and oversized rock.
BELOW GRADE CONSTRUCTION
Basement level construction should not encounter shallow groundwater but seasonal
perched water could occur from springtime runoff and local irrigation. We understand
that the Atkinson Ditch will be lined with a solid pipe. Subsurface drainage is
recommended to protect below grade construction. Typically, this consists of foundation
drains and underslab free chaining gravel connected to a gravity outlet. The bedrock is
shallow or outcrops in most of the valley side slopes and could make building excavations
very difficult to dig.
ROADWAY GRADING
We assume grading for the roadway development will be relatively minor. Existing
topsoil, vegetation and debris should be removed from the cut and embankment fill areas.
Slopes greater than 20% should be benched beneath fill areas. The exposed surface
should be moistened to optimum and compacted to at least 95% of standard Proctor
density. Structural fill should then be placed and compacted to the project specifications
and elevations. Cut and fill slopes should be graded at 2 horizontal to 1 vertical or flatter.
Embankment fill should be compacted to at least 95% of standard Proctor density near
optimum moisture content. The on-site soils devoid of vegetation, topsoil, debris and
oversized rock should be suitable for use as structural fill. Positive drainage away from
the road surface and subgrade should be provided.
SURFACE DRAINAGE
Positive surface drainage should be provided around the buildings and throughout the site
to prevent ponding adjacent to structures and roadways. The Atkinson Ditch through the
Job No. 101 126 Ggritecri
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building area should be lined to prevent seepage impact on adjacent sites. The natural
drainages from the upper valley areas and the valley side scopes can probably be used to
provide positive drainage through the property. The soils are susceptible to erosion,
particularly after the vegetation is stripped. Gullying can be expected on unprotected .
slopes unless properly protected.
WATER TANK SITE
An above ground steel water tank is proposed near the southeast end of the project above
County Road 125 (see Figure 2). The tank will be similar to the existing tank located
uphill of County Road 125 west of Lot 6. The proposed tank site is located on a northeast
sloping hillside that consists of relatively stable colluvial deposits above Maroon
Formation. We assume that the tank pad will be developed mainly by cutting and could
transition the colluvial soils and formation rock.
The site should be suitable for the proposed tank based on geotechnical considerations.
The bearing conditions could be variable and have differential settlement potential
between soil and rock areas. The site specific subsurface conditions should be evaluated
for the tank and grading designs.
LIMITATIONS
This report has been prepared in accordance with generally accepted geotechnical
engineering principles and practices in this area at this time. We make no warranty either
express or implied. The conclusions and recommendations submitted in this report are
based upon the data obtained from our site reconnaissance, the exploratory pits dug at the
location indicated on Figure 2, the assumed type of construction and our experience in the
area. Our findings include interpolation and extrapolation of the subsurface conditions
identified at the exploratory pits. Additional exploration and analysis is recommended for
the individual building foundation design.
Job No. 101 126 Gc.-i
_12 -
This report has been prepared for the exclusive use by our client for planning and
preliminary design purposes. We are not responsible for technical interpretations by
others of our information. As the project evolves, we should provide continued
consultation to verify that the recommendations have been appropriately interpreted. We
recommend observation of excavations for bearing conditions and testing of structural fill
by a representative of ow office.
If you have any questions or if we can be of further assistance, please let us know.
Sincerely,
HEPWORTH-PAWLAK GEOTECHNICAL, INC.
Steven L. Pawlak, P.E.
and By:
Ralph G. Mock
Engineering Geologist
SLP/ksw
cc: Sopris Engineering — Attn: Yancy Nichol
Job No. 101 126
C ljtech
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REFERENCES
Hepworth — Pawlak Geotechnical, ,Inc. 2001, Preliminary Geotechnical Study, Proposed
Springridge Place Phase 11, County Road 125, Garfield Count}; Colorado,
Prepared for The Greenwald Children's Trust, Job No. 101 126, dated February
26, 2001.
Kirkham, R.M. and Others, 1996, Geology Map of the Cattle Creek Quadrangle,
Garfield County, Colorado: Colorado Geological Survey Open File 96-1.
Kirkham, R.M. and Widmann, B.L., 1997, Geology Map of the Carbondale Quadrangle,
Garfield County, Colorado: Colorado Geological Survey Open File 97-3.
Job No. 101 126
QCIPPm
0 1000f.
1 1
Scale: 1 In. =1000 ft.
Contour Interval: 10 ft.
June 2004
Explanation:
gal
Qaa
Qaf
Qc
Kd
Jm
Jo
TRPcs
PPm
Valley Floor Alluvium
Alluvial Apron
Alluvial Fan
Colluvium
Dakota Sandstone
Morrison Formation
Entrada Sandstone
Chine & State Bridge Formations
Maroon Fonnatian
101 126
HEPWORTH-PAWLAK
GEOTECHNICAL, Inc.
■
Contact:
Approximate boundary of map
units.
Exploratory Pit
Approximate location of
exploratory pit.
Potential Rockiall Start Area:
Approxhnate location of potential
rockfall start zone.
Springridge Place Phase II
Figure 2
Preliminary Geology Map and Exploratory Pit Locations
-•0
-'5
-p .
- 10
Pit 1
Elev=8632'
Pit 8
Elev Q 6502'
wC=8.1
an -w3
-200=68
LLp27
PI=12
' Pit 2
Elev=NA
Pit9
Elev =6570'
Pita
Elev=6522'
WC=9.8
013= 104
-200-58
Pit 19
Eley a 6428'
Pit 4
Elev.= 9428'
'el.WC=8.8
:OA=87
.7,00=74
.P1. 4
•
Pit 11
Eiev= 6501'
LADIES. 1. Exploratory pits were dug on April 22 and 29, 1884 with a rubber tired
backhoe.
2. locations of the exploratory pits were measured approximately by pacing`
from features shown on the site plan provided and later by Instrument
survey by High Country Engineering.
3. Elevations of exploratory pits were determined by High Country
Engineering.
•
4. The exploratory pit locations and elevations should be considered.
accurate only to the degree implied by the method used.
•
5. No free water was encountered in the pits at the time of excavation.
Fluctuations in water level may occur with time.
E. Laboratory Testing Results:
WC = Moisture Content {95} Li. Liquid Limit %
DI) = Dry Density (paf} PI = Plasticity Index %
-200 = Percent passing No. 200 sieve
101 126
Springridge Development
0-
10"
Pit 5
Slav= 6438'
-v
WC=13.0
nDa96
,20071
P1=9
P t 8
Elev= 6443'
oeii
i
Pik 7
EIev-8506'
LEGEND:
TOPSOIL; siltyclay, sandy, organic, brown.
WC=7.6
DD=93
-200=84
CLAY (CL}; silty, sandy, stiff, slightly moist, brown and red, slightly •
calcareous, slightly to moderately. porous.
1/1 8113 AND SAND (IiAL,SM}, clayey, scattered gravel, stiff, slightly moist,
red -brown. Slightly porous and calcareous.
FAYI
GRAVEL (GM); sandy, silty, rock fragments, medium dense, sllghtiy
moist, red -brown.
111 SANDSTONE BEDROCK; very hard, dry, red -brown.
Disturbed Bulk Semple.
2" Diameter Hand Driven Liner Sample.
'F Practical refusal to digging with backhoe.
Logs of Exploratory Pits Pig. 3
4
3
02
1.
to
w
ce
03
5
6
7
8
0.1
1.0 10
APPLIED PRESSURE ksf
1
Moisture Content =g,8
Ory Unit Weight = 97
sampled! Sandy Clay
From: Pit 4 at 6 feet
Camp
Upon
ressi n
Wetting
percent
pcf
Af
0.1
1.0 10
APPLIED PRESSURE — ksf
100
101 126
>`iEITH-P�4WLA SWELL-CONSOLJDAT1ON TEST RESULTS
GEOTECHNICAL, Inc..
Fig. 4
Moisture Content = 9.8
percent Unit Weight =
104 PO
Sample of: Clayey Sandy Silt
Front: Pit 3 @ 5.feet
�.--.
•
Cainressi�
Upon
ett_ng
H
,
_
i
0.1
1.0 10
APPLIED PRESSURE ksf
1
Moisture Content =g,8
Ory Unit Weight = 97
sampled! Sandy Clay
From: Pit 4 at 6 feet
Camp
Upon
ressi n
Wetting
percent
pcf
Af
0.1
1.0 10
APPLIED PRESSURE — ksf
100
101 126
>`iEITH-P�4WLA SWELL-CONSOLJDAT1ON TEST RESULTS
GEOTECHNICAL, Inc..
Fig. 4
COMPRESSION-%
3
4
5
Moisture Content = 13.0
Dry Unit Weight = 95
sampie of:Sandy Clay
From: pit 5 at 6 feet
percent
Pci
0.1
1.0
APPLIED PRESSURE
10
kst
100
101 126
HEPWORTH-PAWLAK
GEOTECHNICAL, Inc.
SWELL -CONSOLIDATION TEST RESULTS
Fig. 5
0
1
O 2
w
O 3
U
4
5
6
7
we1
0
tn2
w
0 3
U
APPLIED PRESSURE — ksf
Moisture Concent = 8.1
Dry Unit Weight = 103
Sample of Sandy clay
From: Pit 8' at 5 feet
Compressio
Upon Wetti g
percent
pcf
0.1
1.0 10
APPLIED PRESSURE — ksf
100
101 126
HEPWORTH-PAWLAK
GEOTECHNICAL, Inc.
SWELL -CONSOLIDATION TEST RESULTS
Fig.
Moisture Content = 7.6 percent
Dry Unit Weight = 93 Pc(
Sample of Sandy Clay
From: Pit 7 at 5 feet
i,
Wetting'
Compression
.
.
NUpon
IIEI
ri: 1G 1n tnn
APPLIED PRESSURE — ksf
Moisture Concent = 8.1
Dry Unit Weight = 103
Sample of Sandy clay
From: Pit 8' at 5 feet
Compressio
Upon Wetti g
percent
pcf
0.1
1.0 10
APPLIED PRESSURE — ksf
100
101 126
HEPWORTH-PAWLAK
GEOTECHNICAL, Inc.
SWELL -CONSOLIDATION TEST RESULTS
Fig.
HEPWORTH-PAWLAK GEOTECHNICAL, INC.
TABLE!
SUMMARY OF LABORATORY TEST RESULTS
JOB NO. 101 126
SAMPLE LOCATION
NATURAL
MOISTURE
CONTENT
{961 .
NATURAL
GRADATION
PERCENT
ATTERBERG UNITS
UNCONFINED
COMPRESSIVE
STRENGTH
IPSFI
SOIL OR
BEDROCK TYPE
PIT
DEPTH
Ueetl
DRY
DENSITY
Ipcfl
GRAVEL
1%i
SAND
MI
PASSING
NO. 200
• SIEVE
LIQUID
LIMIT
19121,
PLASTIC
INDEX
1%1
3 -
5
9.8
104
56
Clayey Sandy Silt
4
6
8.8
97
74
26
8
Sandy Clay
5
6
'13.0
95
71
25
9
Sandy Clay
7
5
7.6
93
64
Sandy Clay
8
5
8.1
103
68
27
12
Sandy Clay