HomeMy WebLinkAboutSoils Report 08.10.2017HPKU MAR
Geotechnical Engineering 1 Engineering Geology
Materials Testing 1 Environmental
5020 County Road 154
Glenwood Springs, CO 81601
Phone: (970) 945-7988
Fax: (970) 945-8454
Email: hpkglenwood@kumarusa.com
Office Locations: Parker, Glenwood Springs, and Silverthorne, Colorado
SUBSOIL STUDY
FOR FOUNDATION DESIGN
PROPOSED RESIDENCE
LOT 13, COTTONWOOD HOLLOW
5000 CATTLE CREEK ROAD
GARFIELD COUNTY, COLORADO
PROJECT NO. 17-7-567
AUGUST 10, 2017
PREPARED FOR:
CHRIS ERICKSON
P. O. BOX 3782
BASALT, COLORADO 81621
(chrisericksonart @gmaii.com)
ECEIVE1
AUG 1 5 2017
GApRFIELDCOUN-ice,'
)i4 mtiN I I iDEvI..l.opuj.?
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY - 1 -
BACKGROUND INFORMATION - 1 -
PROPOSED CONSTRUCTION - 1
SITE CONDITIONS - 2 -
GEOLOGIC CONDITIONS 2 -
GEOLOGIC HAZARD EVALUATION _ 3 _
SUBSIDENCE POTENTIAL 3 _
FIELD EXPLORATION - 4 -.
SUBSURFACE CONDITIONS - 4 -
DESIGN RECOMMENDATIONS _ S _
FOUNDATIONS _ S
FOUNDATION AND RETAINING WALLS.... - 6 -
FLOORSLABS -7-
UNDERDRAIN SYSTEM _ 8
SITE GRADING - 8 _
SURFACE DRAINAGE - 9 -
LIMITATIONS - 9 -
REFERENCES - 11 -
FIGURE 1 - LOCATION OF EXPLORATORY BORING
FIGURE 2 - LOG OF EXPLORATORY BORING
FIGURE 3 - GRADATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
Project No. 17-7-567
H-P:KUMAR
PURPOSE AND SCOPE OF STUDY
This report presents the results of a subsoil study for a proposed residence to be located on Lot
13, Cottonwood Hollow, 5000 Cattle Creek Road (County Road 113), Garfield County,
Colorado. The project site is shown on Figure 1. The purpose of the study was to develop
recommendations for the foundation and grading designs. The study was conducted as
supplemental services to Hepworth-Pawlak Geotechnical (now HP/Kumar) agreement for
geotechnical engineering services to Chris Erickson dated July 20, 2017.
An exploratory boring was drilled to obtain information on the subsurface conditions. Samples
of the subsoils obtained during the field exploration were tested in the laboratory to determine
their classification and other engineering characteristics. The results of the field exploration and •
laboratory testing were analyzed to develop recommendations for foundation types, depths and
allowable pressures for the proposed building foundation, as well as for the site grading. This
report summarizes the data obtained during this study and presents our conclusions, design
recommendations and other geotechnical engineering considerations based on the proposed
construction and the subsurface conditions encountered. A discussion of the geologic conditions
at the site are included in the report.
BACKGROUND INFORMATION
Hepworth-Pawlak Geotechnical previously reviewed the subject site conditions and reported the
findings in a report dated April 18, 2016, Job No. 116 110A. That report provided preliminary
foundation design recommendations based on the soils exposed in the existing cut excavation at
the site and a general discussion of the existing cut slope and geologic conditions. The County
has requested a subsoil study be performed and additional discussion and recommendations with
respect to hillside stability, the existing cut slope and potential geologic hazards at the site.
PROPOSED CONSTRUCTION
The building will be one story wood frame structure over a walkout basement level with an
attached garage at the basement level located on the site as shown on Figure 1. Ground floors
H-P%KUMAR
Project No. 17-7-567
-2 -
will be slab -on -grade. The uphill building foundation walls will retain the lower part (about 15
feet) of the existing cut slope 011 the north side. Site retaining walls up to about 10 feet high will
retain the remainder of the existing cut on the north side of the residence as well as the portion of
the existing uphill driveway cut near the residence. Swales will be located above the walls and
drain provided behind the walls per the current plans. Grading for the structure will require
shallow cuts on the order of 3 to 4 feet below the existing relatively flat excavation subgrade.
We assume relatively light foundation loadings, typical of the proposed type of construction.
If building loadings, location or grading plans change significantly from those described above,
we should be notified to re-evaluate the recommendations contained in this report.
SITE CONDITIONS
The site conditions are similar to those discussed in the April 2016 report. Elevation of the site
is about 6660 feet and the property is vacant of structures. A rough cut driveway from County
Road 113 accesses the building site. Vegetation in undisturbed areas consists of moderately
thick pinion and juniper trees with a ground cover of grass and weeds. The site is located on
steeply sloping, south facing hillside above Cattle Creek Road. An area within the building
envelope has been graded relatively flat with cuts up to 25 feet and up to about 5 feet of fill on
the down slope side of the relatively flat bench. The soils exposed in the driveway and building
area cuts consist of basalt gravel, cobbles and boulders in a sandy silty clay matrix. Boulders up
to about 5 feet in diameter were observed on the site. There are subangular basalt cobbles and
small boulders on the ground surface above the building site.
GEOLOGIC CONDITIONS
The site is located near the base of a rolling upland mesa to the north and above Cattle Creek to
the south. The hillside rises about 500 feet in elevation to the mesa top. The mesa was formed
by basalt lava flows which overlie the Eagle Valley Evaporite Formation. The surficial soils
consist of weathered basalt rock in a sandy silt and clay matrix. Basalt flows outcrop near the
mesa top. Geologic hazards identified in the project area include landslides, unstable slopes,
H-P%KUMAR
Project No. 17-7-567
stable in its present condition. The existing 25 feet high cut slope on at the building site, whicl.
-3 -
potentially unstable slopes and rockfall (Lincoln DeVore, 1984). Most of the larger rocks on the
hillside slope above and nearer the residence have recently been removed by the client.
GEOLOGIC HAZARD EVALUATION
Based on our observations at the site and our experience in the area, the building area is not
impacted by snow avalanche, debris avalanche, debris flow or flooding.
No evidence of
landslides was observed at or near the site at the time of our field visit. The hillside appears
is about 15 years old, has shown no movement or evidence of water seepage, and minor signs of
erosion. The existing cut slope at the site appears stable and will be mostly retained by the new
construction which should act to increase the hillside stability with proper design and
construction.
The risk of rockfall is from basalt cobbles and boulders on the ground surface above the building
area on the steep slope appears low based on the subangular nature of the rocks. The rockfall
hazard can be further reduce by removing any additional loose rocks from the hillside above the
building site. Larger rocks on the existing cut face could also be removed as needed for the
protection of workers near the slope.
SUBSIDENCE POTENTIAL
Bedrock of the Pennsylvanian Age Eagle Valley Evaporite underlies the Cottonwood Hollow
Subdivision. These rocks are a sequence of gypsiferious shale, fine-grained sandstone/siltstone
and limestone with some massive beds of gypsum. There is a possibility that massive gypsum
deposits associated with the Eagle Valley Evaporite underlie portions of the property.
Dissolution of the gypsum under certain conditions can cause sinkholes to develop and can
produce areas of localized subsidence. During previous work in the area, several very scattered
sinkholes have been observed. These sinkholes appear similar to others associated with the
Eagle Valley Evaporite in areas of the Roaring Fork River valley.
H-P�KUMAR
Project No. 17-7-567
site throughout the service life of the residence, in our opinion is low;
-4 -
No evidence of subsidence or sinkholes were observed on the property or encountered in the
subsurface materials, however, the exploratory boring was relatively shallow, for foundation
design only. Based on our present knowledge of the subsurface conditions at the site, it can not
be said for certain that sinkholes will not develop.
The risk of future ground subsidence at the
however, the owner should
be aware of the potential for sinkhole development. If further investigation of possible cavities
in the bedrock below the site is desired, we should be contacted.
FIELD EXPLORATION
The field exploration for the project was conducted on July 24, 2017. One exploratory boring
was drilled at the location shown on Figure 1 to evaluate the general subsurface conditions. The
boring was advanced with 4 inch diameter continuous flight auger powered by a truck mounted
CME -45B drill rig. The boring was logged by a representative of H-P/Kumar.
Samples of the subsoils were taken with a 1% inch I.D. spoon sampler. The sampler was driven
into the subsoils at various depths with blows from a 140 pound hammer falling 30 inches. This
test is similar to the standard penetration test described by ASTM Method D-1586. The
penetration resistance values are an indication of the relative density or consistency of the
subsoils. Depths at which the samples were taken and the penetration resistance values are
shown on the Log of Exploratory Boring, Figure 2. The samples were returned to our laboratory
for review by the project engineer and testing.
SUBSURFACE CONDITIONS
A graphic log of the subsurface conditions encountered at the site are shown on Figure 2. The
subsoils consist of relatively dense, basalt gravel, cobbles and boulders in a sandy silty clay
matrix. Drilling in the dense granular soils with auger equipment was difficult due to the cobbles
and boulders and drilling refusal was encountered in the deposit at depths of 5 and 71/2 feet.
H-P�KUMAR
Project No. 17-7-567
_5 -
Laboratory testing performed on samples obtained from the borings included natural moisture
content and gradation analyses. Results of gradation analyses performed on a small diameter
drive sample (minus 11/2 inch fraction) of the granular subsoils are shown on Figure 3. The
laboratory testing is summarized in Table 1.
No free water was encountered in the boring at the time of drilling and the subsoils were slightly
moist to moist.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory boring and the nature of
the proposed construction, we recommend the building be founded with spread footings bearing
on the natural granular soils.
The design and construction criteria presented below should be observed for a spread footing
foundation system.
1) Footings placed on the undisturbed natural granular soils should be designed for
an allowable bearing pressure of 2,000 psf.
The allowable soil bearing pressure
can be increased by 1/3 for retaining wall toe pressures. Based on experience, we
expect settlement of footings designed and constructed as discussed in this section
will be about 1 inch. There could be some additional settlement if the silty clay
matrix soils were to become wetted and precautions should be taken to prevent
wetting of the bearing soils.
2) The footings should have a minimum width of 18 inches for continuous walls and
2 feet for isolated pads.
3) Exterior footings and footings beneath unheated areas should be provided with
adequate soil cover above their bearing elevation for frost protection. Placement
of foundations at least 36 inches below exterior grade is typically used in this
area.
H-Pt-KUMAR
Project No. 17-7-567
-6-
4) Continuous foundation walls should be well reinforced top and bottom to span
local anomalies such as by assuming an unsupported length of at least 12 feet.
Foundation walls acting as retaining structures should also be designed to resist
Iateral earth pressures as discussed in the "Foundation and Retaining Walls"
section of this report.
5) All existing fill, topsoil and any loose or disturbed soils should be removed and
the footing bearing level extended down to the relatively dense natural granular
soils. The exposed soils in footing area should then be moistened and compacted.
6) A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions.
FOUNDATION AND RETAINING WALLS
Foundation walls and retaining structures less than 12 feet in height which are laterally supported
and can be expected to undergo only a slight amount of deflection should be designed for a
lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least 50 pcf
for backfill consisting of the on-site soils. Foundation and retaining walls greater than 12 feet in
height should be designed for a lateral earth pressure of 25H in psf where H is the retained wall
height in feet. Cantilevered retaining structures which are separate from the residence and can be
expected to deflect sufficiently to mobilize the full active earth pressure condition should be
designed for a lateral earth pressure computed on the basis of an equivalent fluid unit weight of
at least 50 pcf for backfill consisting of the on-site soils. The backfill should not contain topsoil
or oversized (plus 6 inch) rocks.
All foundation and retaining structures should be designed for appropriate hydrostatic and
surcharge pressures such as adjacent footings, traffic, construction materials and equipment. The
pressures recommended above assume drained conditions behind the walls and a horizontal
backfill surface. The buildup of water behind a wall or an upward sloping backfill surface will
increase the lateral pressure imposed on a foundation wall or retaining structure. An underdrain
should be provided to prevent hydrostatic pressure buildup behind walls.
H -P- KUMAR
Project No. 17-7-567
_7_
Backfill should be placed in uniform lifts and compacted to at least 90% of the maximum
standard Proctor density at a moisture content near optimum. Backfill placed in pavement and
walkway areas should be compacted to at least 95% of the maximum standard Proctor density.
Care should be taken not to overcompact the backfill or use large equipment near the wall, since
this could cause excessive lateral pressure on the wall. Some settlement of deep foundation wall
backfill should be expected, even if the material is placed correctly, and could result in distress to
facilities constructed on the backfill.
The lateral resistance of foundation or retaining wall footings will be a combination of the
sliding resistance of the footing on the foundation materials and passive earth pressure against
the side of the footing. Resistance to sliding at the bottoms of the footings can be calculated
based on a coefficient of friction of 0.45. Passive pressure of compacted backfill against the
sides of the footings can be calculated using an equivalent fluid unit weight of 375 pcf. The
coefficient of friction and passive pressure values recommended above assume ultimate soil
strength. Suitable factors of safety should be included in the design to limit the strain which will
occur at the ultimate strength, particularly in the case of passive resistance. Fill placed against
the sides of the footings to resist lateral loads can consist of the on-site soils (minus 6 inch size)
compacted to at least 95% of the maximum standard Proctor density at a moisture content near
optimum.
FLOOR SLABS
The natural on-site soils, exclusive of topsoil, are suitable to support lightly loaded slab -on -grade
construction. To reduce the effects of some differential movement, floor slabs should be
separated from all bearing walls and columns with expansion joints which allow unrestrained
vertical movement. Floor slab control joints should be used to reduce damage due to shrinkage
cracking. The requirements for joint spacing and slab reinforcement should be established by the
designer based on experience and the intended slab use. A minimum 4 inch layer of free -
draining gravel should be placed beneath basement level slabs to facilitate drainage. This
material should consist of minus 2 inch aggregate with at least 50% retained on the No. 4 sieve
and less than 2% passing the No. 200 sieve.
H-Pk-KUMAR
Project No, 17-7-567
-8_
All fill materials for support of floor slabs should be compacted to at least 95% of maximum
standard Proctor density at a moisture content near optimum. Required fill can consist of the on-
site granular soils devoid of topsoil and oversized (plus 6 inch) rocks.
UNDERDRAIN SYSTEM
Although free water was not encountered during our exploration, it has been our experience in
the area and where clayey soils are present that local perched groundwater can develop during
times of heavy precipitation or seasonal runoff. Frozen ground during spring runoff can also
create a perched condition. We recommend below -grade construction, such as retaining walls
and basement areas, be protected from wetting and hydrostatic pressure buildup by an underdrain
system.
The drains should consist of drainpipe placed in the bottom of the wall backfill surrounded above
the invert level with free -draining granular material. The drain should be placed at each level of
excavation and at least 1 foot below lowest adjacent finish grade and sloped at a minimum 1% to
a suitable gravity outlet. Free -draining granular material used in the underdrain system should
contain less than 2% passing the No. 200 sieve, less than 50% passing the No. 4 sieve and have a
maximum size of 2 inches. The drain gravel backfill should be at least 11/ feet deep and be
covered by filter fabric such as Mirafi 140N or 160N.
SITE GRADING
The risk of construction -induced slope instability at the site appears low provided the existing cut
is retained as planned an additional fill placed on the downslope side of the existing site is
limited also as planned. Final graded slopes up to about 8 feet high should be no steeper than 11
horizontal to 1 vertical. Final graded slopes taller than about 8 feet high should be no steeper
than 2 horizontal to 1 vertical or retained to limit the exposed cut height to about 8 feet.
Embankment fills should be compacted to at least 95% of the maximum standard Proctor density
near optimum moisture content. Prior to fill placement, the subgrade should be carefully
prepared by removing all vegetation and topsoil and compacting to at least 95% of the maximum
standard Proctor density. The fill should be benched into the portions of the hillside exceeding
20% grade.
H-PtKUMAR
Project No. 17-7-567
9
SURFACE DRAINAGE
Positive surface drainage is an important aspect of the project to divert surface water away from
the residence and prevent wetting of the bearing soils. The following drainage precautions
should be observed during construction and maintained at all times after the residence has been
completed:
1) Inundation of the foundation excavations and underslab areas should be avoided
during construction.
2) Exterior backfill should be adjusted to near optimum moisture and compacted to
at least 95% of the maximum standard Proctor density in pavement and slab areas
and to at least 90% of the maximum standard Proctor density in landscape areas.
3) The ground surface surrounding the exterior of the building should be sloped to
drain away from the foundation in all directions. We recommend a minimum
slope of 12 inches in the first 10 feet in unpaved areas and a minimum slope of 3
inches in the first 10 feet in paved areas. This will likely require a swale above
the building.
4) Free -draining wall backfill should be capped with filter fabric and about 2 feet of
the finer graded on-site finer graded soils to reduce surface water infiltration.
5) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
6) Landscaping which requires regular heavy irrigation should be located at least 5
feet from foundation walls. Consideration should be given to use of xeriscape to
reduce the potential for wetting of soils below the building caused by irrigation.
LIMITATIONS
This study has been conducted 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 the exploratory boring drilled at the location indicated on Figure 1, the proposed type of
construction and our experience in the area. Our services do not include determining the
presence, prevention or possibility of mold or other biological contaminants (MOBC) developing
H -P —KUMAR
Project No. 17-7-567
- 10 -
in the future. If the client is concerned about MOBC, then a professional in this special field of
practice should be consulted. Our findings include extrapolation of the subsurface conditions
identified at the exploratory boring and variations in the subsurface conditions may not become
evident until excavation is performed. If conditions encountered during construction appear
different from those described in this report, we should be notified so that re-evaluation of the
recommendations may be made.
This report has been prepared for the exclusive use by our client for design purposes. We are not
responsible for technical interpretations by others of our information. As the project evolves, we
should provide continued consultation and field services during construction to review and
monitor the implementation of our recommendations, and to verify that the recommendations
have been appropriately interpreted. Significant design changes may require additional analysis
or modifications to the recommendations presented herein. We recommend on-site observation
of excavations and foundation bearing strata and testing of structural fill by a representative of
the geotechnical engineer.
Respectfully Submitted,
H -P KUMAR
Louis E. Eller, Staff Engineer
Reviewed by:
Cp. .6 aro* � f.1 -9c
David A. Young, P.11.
li,;1 32-216 r
raNnq-
DAY/ksw A1� if'kn oe...5tivpst��
144*
cc: Land + Shelter — .leleewp lbw (jeremy@landandshelter.com)
H-PtKUMAR
Project No. 17-7-567
- 11 -
REFERENCES
Lincoln DeVore, January 13, 1984, LDTL Job No. 50538 -GS. General and Engineering
Geology, Cottonwood Hollow Subdivision, Garfield County, Colorado.
H-P?:-_-KUMAR
Project No. 17-7-567
EXISTING
CUT SLOPE
' I
1
1
1
1
1
1
4
1
I 1 \ 1
11 1
1
PROPOSED RESIDENCY
5000 COUNTY RD 13
11\ \\\.\\
30 0 30 60
APPROXIMATE SCALE—FEET
17-7-567
H -P- KUMAR
1-..
1
1
1
1
1
1
1
\\'
LOCATION OF EXPLORATORY BORING
Fig. 1
1-
w
x
f-
a
0
f--- 5
— 10
17-7-567
BORING 1
EL. 6648'
%tr
• a 41/12
• { WC=3.3
/ +4=66
fir -200=13
38/12
iWC=11.6
4 -200=41
LEGEND
,-./4,.
, BASALT GRAVEL AND COBBLES (GC); WITH BOULDERS IN A SANDY SILTY
• CLAY MATRIX. DENSE, SLIGHTLY MOIST TO MOIST, REDDISH BROWN.
41/12
DRIVE SAMPLE, 1 3/8 -INCH I.D. SPLIT SPOON STANDARD PENETRATION
TEST.
DRIVE SAMPLE GLOW COUNT. INDICATES THAT 41 BLOWS OF
A 140 -POUND IIAMMER FALLING 30 INCHES WERE REQUIRED
TO DRIVE THE SAMPLER 12 INCHES,
PRACTICAL AUGER REFUSAL. WHERE SHOWN ABOVE BOTTOM OF HOLE
INDICATES MULTIPLE ATTEMPTS MADE ADVANCE THE BORING.
NOTES
1. THE EXPLORATORY BORING WAS DRILLED ON JULY 24, 2017 WITH A
4 -INCH DIAMETER CONTINUOUS FLIGHT POWER AUGER,
H -P- KUMAR
2. THE LOCATION OF THE EXPLORATORY BORING WAS MEASURED
APPROXIMATELY BY PACING FROM FEATURES SHOWN ON THE SITE PLAN
PROVIDED.
3. THE ELEVATION OF THE EXPLORATORY BORING WAS OBTAINED BY
INTERPOLATION BETWEEN CONTOURS ON THE SITE PLAN PROVIDED.
4. THE EXPLORATORY BORING LOCATION AND ELEVATION SHOULD BE
CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED BY THE METHOD
USED,
5. THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING
LOG REPRESENT THE APPROXIMATE BOUNDARIES BETWEEN MATERIAL
TYPES AND THE TRANSITIONS MAY BE GRADUAL,
6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORING AT THE TIME OF
DRILLING.
7. LABORATORY TEST RESULTS;
WC = WATER CONTENT (%) (ASTM D 2216);
+4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM D 422);
-200 = PERCENTAGE PASSING NO, 200 SIEVE (ASTM D 1140).
LOG OF EXPLORATORY BORING
Fig. 2
HYDROMETER ANALYSIS
SIEVE ANALYSIS
100
24 0143 7 FIRS
.1�
'LB
TIME READINGS
49IN
OS.
.�
_ 100
3YAt♦OA110 SEMIS
. 4• 0 16 1. 4:
CLEAR SOUARC OPENINGS
s
0
�_-
11
90
�+r.reeM
_10
e°.................1-
20
...:
70
>✓11
so
-
�
4
MI—
—
-{1—
t BG
Mil
MOM
��r
40 8
I
1
—
Q
50
!
I
}
so
r
r
I
1
FPI'
40
1
I
{
�1
I
so
4
1
I
so
1
1
i
I
I
0—
70
20
Mi
{
1
BO
e»
1•
10
0
I i
1 El
rE1 —t-1
—3--ri
C 1
1
—t—r—
rrr��
100
.001 .002 .009
.000 .019 .037
4473
DIAMETER
.150 '.550
OF PARTICLES
1 .900
1.
IN MILLIMETERS
d 1 7.30 4.75
9.5
15
35.1 76.9 129
1n
250
CLAY TO SILT
SAND
GRAVEL
MEDIUM 1COARSE
FINE 1 COARSE
COBBLESFINE
GRAVEL 66 % SAND 21 % SILT AND CLAY 13
LIQUID LIMIT PLASTICITY INDEX
SAMPLE OF: Clayey Silty Sandy Gravel FROM: Boring 1 ® 2.5'
These test results apply only to the
samples which wore tested. The
testing report shall nol be reproduced,
except 10 full, wilhoui the wrilien
approval of Kumar & Associolee, Inc.
Slave analysis testing Is performed in
accordance wllh ASTM 0422, ASTM C136
and/or ASTM D1140.
17-7-567
FI -P- KUMAR
GRADATION TEST RESULTS
Fig. 3
-P�INMAR
TABLE 1
SUMMARY OF LABORATORY TEST RESULTS
Project No. 17-7-567
SAMPLE LOCATION NATURAL
i NATURAL
' DRY
DENSITY
(pot)
' CRAOATiON L ATTERBERG LIMITS
SOIL TYPE
[BORING
DEPTH
(ft)
MOISTURE
CONTENT
(%)
• PERCENT 1
GRAVEL I SAND PASSING LIQUID
I (%) (%) NO. 200 SIEVE LIMIT
I (%)
PLASTIC
INDEX
(%)
UNCONFINED
COMPRESSIVE
STRENGTH
(PSF)
1
21
3.3 66
21 13
Clayey Silty Sandy Gravel
5
11.8
41
Clayey Silty Sandy Gravel