HomeMy WebLinkAboutSubsoils Report for Foundation Design (2)I Crt *ffi1[,ff#fffir*,yfd**
An Employcc Ornad Compony
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email : kaglenwood(@kumarusa.com
www.kumarusa.com
Office I-ocations: Dorver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
1Ks
oP*l
{tE
(Zo*lp^- & pft a*.*.n_4$Ly
f-kcrg rz+f.rof aR)Nr ftslb .?., uk{1+ €fAssu^'te5; l5oaPs6 ts orslatrrga;g
PRELIMINARY SUBSOIL STUDY
FOR FOUNDATION DESIGN
PROPOSED RESIDENCES
LOTS I - 4, BLOCK 1 AND LOTS I - 4, BLOCK 2
THE FAIRWAYS, BATTLEMENT MESA
HOGAN CIRCLE
GARFIELD COUNTY, COLORADO
PROJECT NO.2r-7-229
JULY 2l,2v2l
PREPARED FOR:
VINCENT TOMASULO
c/o RUSSELL CARTWRIGHT
35 WILLOWVIEW WAY
PARACHUTEO COLORADO 81635
russecart@gmail.com
l,\ .
\r'
3L
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STT]DY
PROPOSED CONSTRUCTION
SITE CONDITIONS
FIELD E)GLORATION
SUBSURFACE CONDITIONS
FOI.]NDATION BEARING CONDITIONS
DESIGN RECOMMENDATIONS
FOI.]NDATIONS
FOUNDATION AND RETAINING WALLS
FLOOR SLABS
UNDERDRAIN SYSTEM
SURFACE DRAINAGE
LIMITATIONS.........
FIGURE I - LOCATION OF DGLORATORY BORINGS
FIGURE 2 - LOGS OF E)GLORATORY BORINGS
FIGURE 3 - LEGEND AND NOTES
FIGURE 4 through 6 - SWELL-CONSOLIDATION TEST RESULTS
FIGURE 7 - GRADATION TEST RESULTS
TABLE 1- SUMMARY OF LABORATORY TEST RESULTS
I
I
1
n
-2-
-3-
--t-
aJ
4
5
5
6
6
Kumar &Associates, lnc. o Project No-21-7-229
PURPOSE AND SCOPE OF STUDY
This report presents the results of a preliminary subsoil study for proposed residences to be
located on Lots 1 to 4, Block I and Lots I to 4, Block Z,The Fairways, Battlement Mesa, Hogan
Circle, Garfield County, Colorado. The project site is shown on Figure 1. The purpose of the
study was to develop preliminary recommendations for foundation designs. The study was
conducted in accordance with our agreement for geotechnical engineering services to Russell
Cartwright dated March 1,2021.
A field exploration program consisting of exploratory borings was conducted 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, compressibility or
swell and other engineering characteristics. The results of the field exploration and laboratory
testing were analyzed to develop resommendations for foundation types, depths and allowable
pressures for the proposed building foundation. 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.
PROPOSED CONSTRUCTION
The proposed residences will be one- and two- story structures with attached garages. Ground
floors will be structural over crawlspace for the living areas and slab-on-grade for the garage.
Grading for the structures is assumed to be relatively minor with cut depths between about 2 to 5
feet. 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 subject site was vacant at the time of our field exploration. The ground surface is sloping
down to the east at an estimated grade of about 10 percent. Vegetation consists of grass and
sparse weeds.
Kumar &Associates, lnc. o Project No.21-7-229
n
F'IELD EXPLORATION
The field exploration for the project was conducted on March 26,2027. Four exploratory
borings were drilled at the locations shown on Figure 1 to evaluate the subsurface conditions.
The borings were advanced with 4-inch diameter continuous flight augers powered by a truck-
mounted CME-45B drill rig. The borings were logged by a representative of Kumar &
Associates, Inc.
Samples of the subsoils were taken with l}h-inch and 2-inch I.D. spoon samplers. The samplers
were 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 Logs of Exploratory Borings, Figure 2. The samples were retumed to our
laboratory for review by the project engineer and testing.
SUBSURFACE CONDITIONS
Graphic logs of the subsurface conditions encountered at the site are shown on Figure 2. The
subsoils consist of about I foot of topsoil overlying mainly sandy silt soils to depths between
12 and 20 feet where dense, silty clayey sand and gravel with cobbles was encountered to the
maximum explored depth of 24 feet deep. Drilling in the dense granular soils with auger
equipment was difficult due to the cobbles and possible boulders and drilling refusal was
encountered in the deposit at Borings 1 and 4.
Laboratory testing performed on samples obtained from the borings included natural moisture
content and density and gradation analyses. Results of swell-consolidation testing performed on
relatively undisturbed drive samples of the silt soils, presented on Figures 4 through 6, indicate
low compressibility under existing low moisture conditions and light loading and varied low
collapse to low swell potential when wetted under constant light surcharge. Results of gradation
analyses performed on small diameter drive samples (minus l%-inch fraction) of the coarse
granular subsoils are shown on Figure 7. The laboratory testing is summarizedin Table 1.
No free water was encountered in the borings at the time of drilling and the subsoils were
slightly moist.
Kumar &Associates, lnc. o Project No.21-7-229
J
FOUNDATION BEARING CONDITIONS
The upper silt soils encountered in the borings possess low bearing capacity and varied
compression/expansion potential when wetted. Our experience indicated the upper fine-grained
soils are mainly compressible when wetted under loading. The underlying gravel soils possess
moderate bearing capacity and typically low settlement potential. Spread footings placed on the
upper fine-grained soils can be used for support of the proposed residences with a risk of
foundation movement. A lower risk option would be to extend the bearing level down to the
underlying gravel soils with a deep foundation system such as drilled piers or micro-piles.
Provided below are recommendations for a spread footing foundation system. If
recommendations for a deep foundation system are desired, we should be contacted to provide
them.
DESIGN RECOMMENDATIONS
FOUNDATIONS
Considering the subsurface conditions encountered in the exploratory borings and the nature of
the proposed construction, we recommend the building be founded with spread footings bearing
on the natural fine-grained soils.
The design and construction criteria presented below should be observed for a spread footing
foundation system.
1) Footings placed on the undisturbed natural fine-grained soils should be designed
for an allowable bearing pressure €],SOO pst,Pased on experience, we expect
initial settlement of footings designed and constructed as discussed in this section
will be about I inch or less. Additional post-construction differential foundation
movement could occur if the bearing soils become wetted. The magnitude of
additional movement would depend on the depth and extent of wetting but could
be on the order of about I to 1% inches.
2) The footings should have a minimum width of 1-8_@-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
offoundationsatlea[@elowexteriorgradeistypicallyusedinthis
area.
4) Continuous foundation walls should be heavily reinforced top and bottom to span
local anomalies such as by assuming an unsupported length of at least 14 feet.
Kumar &Associates, lnc. o Project No.21-7-229
-4-
Foundation walls acting as retaining structures should also be designed to resist
lateral earth pressures as discussed in the "Foundation and Retaining Walls"
section of this report.
Topsoil and any loose or disturbed soils should be removed and the footing
bearing level extended down to the firm natural fine-grained soils. The exposed
soils in footing area should then be moistened and compacted.
6)A tative of the geotechni cal engineer should observe all
excavafions to concrete to evaluate beaing conditions.
FOTINDATION AND RETAINING WALLS
Foundation walls and retaining structures 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 55 pcf for backfill consisting
of the on-site fine-grained soils. Cantilevered retaining structures which are separate from the
residences 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 45 pcf for backfill consisting of the on-site fine-grained soils.
All foundation and retaining structures should be designed for appropriate hydrostatic and
surcharge pressures such as adjacent footings, trafftc, 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.
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 95o/o 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 bacldll.
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 0.35. Passive pressure backfill against the
s)
Kumar &Associates, lnc. o
of
Project No. 21-7-229
5
sides of the footings can be calculated using an equivalent fluid unit weight of 350 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 should be compacted to at least 95Yo 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 with a risk of movement similar to that described above for footings. 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 2o/o passing the No. 200
sieve.
All fill materials for support of floor slabs should be compacted to at least 95o/o of maximum
standard Proctor density at a moisture content near optimum. Required fill can consist of the
on-site soils devoid of vegetation, topsoil and oversized rock.
UNDERDRAIN SYSTEM
Although free water was not encountered during our exploration, it has been our experience in
the area that local perched groundwater can develop during times of heavy precipitation or
seasonal runoff. Frozen ground during spring runoffcan create a perched condition. V/e
recommend below-grade construction, such as retaining walls, crawlspace (greater than 4 feet
deep) and basement areas (if any), 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 atleast I foot below lowest adjacent finish grade and sloped at a minimum IYoto
a suitable gravity outlet or sump and pump. Free-draining granular material used in the
underdrain system should contain less than 2o/o passing the No. 200 sieve, less than 50% passing
Kumar &Associates, lnc. o Project No. 21-7-225
-6-
the No. 4 sieve and have a maximum size of 2 inches. The drain gravel backfill should be at
least TVzfeet deep. An impervious membrane such as 20 mil PVC should be placed beneath the
drain gravel in a trough shape and attached to the foundation wall with mastic to prevent wetting
of the bearing soils.
SURFACE DRAINAGE
Providing proper surface grading and drainage will be critical to limiting subsurface wetting and
potential building movement. The following drainage precautions should be observed during
construction and maintained at all times after the residences have been completed:
1) Inundation ofthe 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 90o/o 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 l0 feet in unpaved areas and a minimum slope of
3 inches in the first 10 feet in paved areas. Free-draining wall backfill should be
covered with filter fabric and capped with about 2 feet of the on-site soils to
reduce surface water infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of all
baclcfill.
5) Landscaping which requires regular heavy irrigation should be located at least 10
feet from foundation walls. Consideration should be given to the use of xeriscape
to limit potential wetting of soils below the foundation caused by irrigation.
LIMITATIONS
This study has been conducted in accordance with generally accepted geotechnical engineering
principles and practices in this area atthis 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 borings drilled at the locations 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
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 interpolation and extrapolation of the
Kumar &Associates, lnc. o Project No.21-7-229
-7 -
subsurface conditions identified at the exploratory borings 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 bee'n prepared for the exclusive use by our client for planning and preliminary
design pu{poses. 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
veriff that the recornmendations 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,
Kucnar & Asscciates, [nc"
James H. Parsons, P.E.
Reviewed by:
ffi"/.
Steven L. Pawlak, P.E.
JHPlkac
lr
W
58660
Kumar & As$ociates, lne. "l Project No. 21-7"223
BORING
lon
BORING
\4,yIl
I
*lv
4.,.
,lI,trzrg{i
tI
4,/t;,f
d_
tt!,HT"lt
I
6
r9a tler \
A
A$*
t
t
I
tt LO?I| **_- ll5! 50fr
1+)BORING I'"
bntt
,d'vlutrw
a
MCf )
N6C',s62I',r
dr ar(&{69
I 81.72'l.pnl ed iA*
coulixl A..il tutr c
aFflt sPA(a h4;114t/.\a v,utY {*Jtrt}tr
50 0
APPROXIMATE SCALE-FEET
Fig. 1LOCATION OF EXPLORATORY BORINGS21-7-229 Kumar & Associates
a
BORING 1 BORING 2 BORING 3 BORING 4
0 2s/12
WC=4.8
DD=98
-200--92
0
4s/12 45/12
WC=5.7
DD=1 07
5
22/12
WC=5.8
DD=1 01
26/12
24/12
2s/12
WC=5.8
DD=104
23/12
5s/12
18/12
WC=4.0
DD=1 05
5
23/12 24/t2
10 10
24/12 22/t2
WC=4.3
DD=99
24/12
WC=6.4
DD=99
25/12
WC=4.8
DD=1 09
FLI
lr.afL
I-F
o_lrlo
15 40/12 e2/12
25/6, 5O/5
WC=4.6 15
F
rIJIJfL
IIF
o_lrlo
31 /12
WC=5.5 +4=26
-2OO=43DD=1 1 5
-2OO=94
20 20
43/12 50/ 1 50/2
25 25
50 30
21 -7-229 Kumar & Associates LOGS OF EXPLORATORY BORINGS Fig. 2
I
f
LEGEND
Nlroesoru: SILT, sANDy, oRcANlcs, FIRM, sLtcHTLY Motsr, BRowN.
N
V',,, (ML): SLIGHTLY SANDY TO SANDY, SANDIER W]TH DEPTH, SLIGHTLY CI.AYEY, SLIGHTLY
fficlucane6us, vcnv srlFF To HARD, SLIcHTLY Molsr, TAN.
lE--.u
fficRAvEL (CC-eU): SANDY, SILTY, CI-AYEY, COBBLES, POSSIBLE BOULDERS, DENSE, SLIGHTLY
MOIST, GREY BROWN.
F
i
DRIVE SAMPLE, 2-INCH I.D. CALIFORNIA LINER SAMPLE.
DRTVE SAMPLE, 1 3/8-INCH l.D. SPLIT SPOON STANDARD PENETRATION TEST.
/^1.6 DRIVE SAMPLE BLOW COUNT' INDICATES THAT 49 BLOWS OF A 140-POUND HAMMER'rr/ tz FALLTNG SO TNCHES WERE REQUIRED TO DRIVE THE SAMPLER 12 INCHES.
I enlcncAL AUGER REFUSAL.
NOTES
1. THE EXPLORATORY BORINGS WERE DRILLED ON MARCH 26, 2021 WITH A 4-INCH DIAMETER
CONTINUOUS-FLIGHT POWER AUGER.
2. THE LOCATIONS OF THE EXPLORATORY BORINGS WERE MEASURED APPROXIMATELY BY PACING
FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED'
5. THE ELEVATIONS OF THE EXPLORATORY BORINGS WERE NOT MEASURED AND THE LOGS ARE
PLOTTED TO DEPTH.
4. THE EXPLORATORY BORING LOCATIONS SHOULD BE CONSIDERED ACCURATE ONLY TO THE
DEGREE IMPLIED BY THE METHOD USED.
5, THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING LOGS REPRESENT THE
APPROXIMATE BOUNDARIES BETWEEN MATERIAL TYPES AND THE TRANSITIONS MAY BE GRADUAL.
6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORINGS AT THE TIME OF DRILLING.
7. I-ABORATORY TEST RESULTS:
wc = wATER CONTENT (%) (ASTM D2216):
DD = DRY DENSITY (pct) (lsru D2216);
+4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM D6913);
-200= PERCENTAGE PASSING NO. 200 SIEVE (ASTM 01140).
21-7-229 Kumar & Associates LEGEND AND NOTES Fig. 3
I
SAMPLE OF: Sondy Silt
FROM:BoringlOl'
WC = 5.8 X, DD = 101 pcf
NO MOVEMENT UPON
WETTING
I
x
JJIJ
=tn
I
zoF
o
=o
anzoo
1
0
-1
-2
-3
t.0 t0
)e
JJlrl-a
I
zo
F
o
Joazo(J
2
1
0
-1
-2
1 t.0 10
SAMPLE OF: Silt ond Cloy
FROM:Boring1O15'
WC = 5.5 %, DD = 115 pcf
><
I
!
j-
I
i
EXPANSION UNDER CONSTANT
PRESSURE UPON WETTING
I
i
1t1
nr t * dltr oDct 6t b fr.
EnrLa t-bd. th. iEtE |ryt
$.ll noa ba nndu6d. -r*t h
tu|, rihqn ta rdtLn e6d of&mr 6d lrutob. lnc *.llDdrlddld Idh6 Eft.tFd hd'E ff ail o-4ga
21-7-229 Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS Fig. 4
E
1
)q
JJI!
=U'
I
zo
F
o
Jonz.o
C)
0
-1
2
5
-4
_E
APPLIED 100
N
JJtd
=a
I
z.o
F
o
=oU'zoo
1
0
-1
-2
-5
1.0 APPLIED
SAMPLE OF: Sondy Silt
FROM:Boring2e^2.5'
IVC = 5.7 X, DD = 1A7 pcl
ADDITIONAL COMPRESSION
UNDER CONSTANT PRESSURE
DUE TO WETTING
:]
i1
\
I
SAMPLE OF: Sondy Silt
FROM:Borlng2OlO'
WC = 4.5 %, DD = 99 pcf
I
I
I
I
I
EXPANSION UNDER CONSTANT
PRESSURE UPON WETTING
I
I
21-7-229 Kumar & Associates SWELL-CONSOLIDATION TEST RESULTS Fig. 5
SAMPLE OF: Sondy Silt
FROM:Boring5O4'
WC = 5.8 f, DD = 104 pcf
t-_
EXPANSION UNDER CONSTANT
PRESSURE UPON WETTING
\
N
JJul
=a
I
zotr
ct
Jovtzo(J
N
JJul3
af,
I
z.otr
o
Jotnz.oo
1
0
1
2
1
0
1
2
APPLIED
APPLIED
SAMPLE OF: Sondy Silt
FROM: Borlng 4 O 10'
WC = 4.8 %, DD = 109 pcf
EXPANSION UNDER CONSTANT
PRESSURE UPON WEfiING
ns d dlt .tDt of b frarnpb ffid, lh. tdlD reort
Jro[ noa b. Eptgducad, ac.$ h
lul. rihcn tF rrltLn sod oalffircnd bdta lno Sloil*tlum trlbg erlb.fit d hBddE rtth ISII lF,ts,ta
Fig. 6SWELL-CONSOLIDATION TEST RESULTSKumar & Associates21-7-229
3
,i
ii
a
E
H
E
too
90
co
70
ao
50
6
50
m
to
o
10
20
30
&
50
ao
70
lo
eo
too
EI
u
E
F
IN
CI.AY TO SILT COBBLES
GRAVEL 26 X SAND 31
LIQUID LIXIT
SAMPLE OF: Sllty Gloyey Sond ond Grovel
x
PLASTICITY INOEX
SILT AND CI-AY 13 X
FROM: Borlng 1O11'
Th... t d r.rulh qppry onry lo ft.
iEllng nporl rhall nol b. roprcduo.d,
axcaDl ln fulL vilhoul |fi. tdit n
ooorcwl of Kumor & A$slolt , lnc.
SLin onolnlr l.dlno h mr{omcd ln
occordonci rlth ASfil 06013. asTv D7g2E,
Astlt C150 andlor ASIX Dll40,
SIEVE ANALYSISHYDROMETER ANALYSIS
CI.EAR SQI'ARE OPEIIIXGS
at). tta. t 1t..4n 16 lln aid Itlaatxl,a HRS 7 HRSut! lillr
IIHE REIDII'G
icrt{
i
,ll , ,,
GRAVELSAND
COARSEFINErrEDruM lcoARSE FINE
21 -7-229 Kumar & Associates GRADATION TEST RESULTS Fis. 7
I (art Hffil['*sfffi*,'13;n''**
TABLE 1
SUMMARY OF LABORATORY TEST RESULTS
1
BORING
J
2
4
lfi)
DEPTH
SAIIIPLE LOCATION
I
10
2%
I 5
4
I 4
1 0
5
I 0
4
4.3
5.7
5.5
3.8
l%l
NATURAL
IIOISTURE
CONTENT
4.0
6.4
3.8
48
4.6
4.8
115
1 0 I
NATURAL
DRY
DENSITY
(pcfl
104
98
99
107
109
103
99
26 -t I
92
94
43
Silt and Clay
Sandy Silt
SOIL TYPE
GRADATION ATTERBERG LI]IIITS
LIQUID LI]IIIT
PERCENT
PASSING NO.
200 stB/E
UNCONFINED
cotrlPREssr\tE
STRENGTH
GRAVEL
(%)
SAf'lD
(%)
PLASTIC
INDEX
Sandy Silt
Sandy Silt
Slightly Sandy Silt
Sandy Silt
Sandy Silt
Silty Clayey Sand and
Gravel
Sandy Silt
Sandy Silt
No. 21-7-229