HomeMy WebLinkAboutEngineering Report 02.27.2015Grtech
HEPWORTH-PAWLAK GEOTECHNICAL
Hepworth-Pawlak Geotechnical, Inc.
5020 County Road 154
Glenwood Springs, Colorado 81601
Phone: 970-945-7988
Fax: 970-945-8454
Email: hpgeo@hpgeotech.com
GEOTECHNICAL ENGINEERING STUDY
PROPOSED FEDEX GROUND SORT FACILITY
COUNTY ROAD 154 NEAR STATE HIGHWAY 82
GARFIELD COUNTY, COLORADO
JOB NO. 115 023A
FEBRUARY 27, 2015
PREPARED FOR:
KW GLENWOOD SPRINGS, LLC
ATTN: KEVIN KIERNAN
941 ORANGE AVENUE, #512
CORONADO, CALIFORNIA 92118
ke%in,a thei:iernancompanies.com
TABLE OF CONTENTS
PURPOSE AND SCOPE OF STUDY - I -
PROPOSED CONSTRUCTION - I -
SITE CONDITIONS - 2 -
SUBSIDENCE POTENTIAL AND GEOLOGIC CONDITIONS -
FIELD EXPLORATION - 3 -
SUBSURFACE CONDITIONS - 4 -
FOUNDATION BEARING CONDITIONS__ ..... ..... ...... ......... ...... 5 -
DESIGN RECOMMENDATIONS - 5 -
FOUNDATIONS .......... . .. . ..... ... .... ________ ... . ............. 5 -
FOUNDATION AND RETAINING WALLS ..... - ... ... ......... - 7 -
FLOOR SLABS - 8 .
UNDERDRAIN SYSTEM . .. ......... .. ............ _ ... ..... ....... 8 -
SITE GRADING - 9 -
PAVEMENT SECTION ... . ..... .... . .. ... . . ............. MM••••.3 ..... 9 -
SURFACE DRAINAGE lo.
LIMITATIONS - I I -
FIGURE 1 - LOCATION OF EXPLORATORY BORINGS AND PITS
FIGURES 2 AND 3- LOGS OF EXPLORATORY BORINGS
FIGURE 4- LEGEND AND NOTES -EXPLORATORY BORINGS
FIGURE 5 - LOGS OF EXPLORATORY PITS
FIGURES 6 AND 7 SWELL -CONSOLIDATION TEST RESULTS
FIGURES 8 TI IROUGI - GRADATION TEST RESULTS
FIGURE 11 - USDA GRADATION TEST RESULTS
TABLE I - SUMMARY OF LABORATORY TEST RESULTS
TABLE 2- PERCOLATION TEST RESULTS
Job No. 115 023A GJtech
PURPOSE AND SCOPE OF STUDY
This report presents the results of a geotechnical engineering study for the proposed
FedEx Ground Sort Facility to be located at County Road 154 near State Highway 82,
Garfield County, Colorado. The project site is shown on Figure 1. The purpose of the
study was to develop recommendations for the foundation, grading and pavement
designs. The study was conducted in accordance with our proposal for geotechnical
engineering services to KW Glenwood Springs, LLC dated January 15, 2015.
A field exploration program consisting of exploratory borings and pits 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 recommendations for
foundation types, depths and allowable pressures for the proposed building foundation,
site grading and pavement sections. 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 building will be a single story structure with office and package sorting
areas and slab -on -grade floor. The building will be surrounded by drives and parking that
will be asphalt paved. The depressed dock will be located at the northeast side of the
building and the ramp paved with concrete. Grading for the structure and surrounding
paved surfaced areas will typically have shallow cut and fill grading up to about 4 to 5
feet deep. We assume relatively light continuous wall and moderate column foundation
loadings, typical of the proposed type of construction. An individual septic disposal
system is proposed for onsite sewage disposal. A 20,000 gallon steel water storage tank
will be provided at the uphill, east side of the property. The overall layout of the
proposed facilities is shown on Figure 1.
Join No. 115 023A
GeZtech
-2 -
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 proposed development is located just southwest of County Road 154 (Old State
Highway 82) near the intersection with State Highway 82 and mostly consists of a vacant,
irrigated pasture. A gravel ranch road crosses the west end of the property. The ground
surface slopes moderately down from CR 154 then flattens to nearly level through the
proposed building site then moderately before sloping steeply down to the Roaring Fork
River off the property to the south. InterMountain Waste & Recycling is located
immediately south (and will be the entrance) of the project site, irrigated field is located
to the north and sage covered, non -irrigated land is located to the west. Vegetation
consists mostly of grass and weeds on the project site except for the west end where there
is sage brush. There was 6 to 8 inches of snow on the site at the time of drilling.
SUBSIDENCE POTENTIAL AND GEOLOGIC CONDITIONS
Bedrock of the Pennsylvanian age Eagle Valley Formation underlies the project site.
These rocks are a sequence of shale, fine-grained sandstone and siltstone and can contain
beds or inclusions of gypsum which is in turn underlain by Eagle Valley Evaporite which
can contain 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 studies in the area, several sinkholes have
been observed scattered throughout the Roaring Fork River valley which appear similar to
others associated with the Eagle Valley Evaporite.
Sinkholes were not observed in the immediate area of the project site. No evidence of
cavities was encountered in the subsurface materials; however, the exploratory borings
were relatively shallow, for foundation design only. Based on our present knowledge of
the subsurface conditions at the site, it cannot be said for certain that sinkholes will not
develop. The risk of future ground subsidence on the project site throughout the service
Job No, 115 023A
H&tech
-3 -
life of the proposed facilities, in our opinion, is low; however, the owner should be made
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.
Red siltstone of the Maroon Formation is exposed to the northeast across State Highway
82. Grey to tan siltstone of the Eagle Valley Formation underlies the Maroon at roughly
the bottom of river, on the order of 60 feet below the project site. The formation rock
bedding is generally relatively flat lying below the project site to moderately dipping into
the valley side northeast of the project site. At these bedding grades, the formation rock
should be relatively stable against slope instability. The formation on the hillside is
covered with relatively shallow colluvium with a thicker wedge of slope wash deposit
along the toe of the hillside which State Highway 82 alignment roughly follows in the
section above the project site. StnalI ephemeral drainages have developed which cut
through the colluvial slope wash deposits and coalesce below State Highway 82 and CR
154 to form relatively fine-grained alluvial fan deposits on top of the river terrace
deposits which underlie the project site and extend down to the Roaring Fork River.
These river terrace deposits consist of clast supported gravel, cobbles and boulders in a
silty sand matrix and in turn are underlain by bedrock of the Eagle Valley Formation.
Based on our review, there are no significant geologic hazards that would make the
project infeasible and their potential impacts can be mitigated with good engineering and
construction practices.
FIELD EXPLORATION
The field exploration for the project was conducted between January 27 and February 24,
2015. Fourteen exploratory borings were drilled in the building and surrounding area and
two profile pits and 4 percolation holes were dug in the proposed septic disposal area 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 CME -45B drill rig
and the pits were dug with a rubber -tired backhoe. The borings and pits were logged by a
representative of Hepworth-Pawlak Geotechnical, Inc.
Job No. 115 023A
Czech
-4 -
Samples of the subsoils were taken with 1% inch and 2 inch LD. spoon samplers in the
boreholes and by disturbed methods in the pits. 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, Figures 2, 3 and 5. The samples were
returned to our Iaboratory for review by the project engineer and testing.
SUBSURFACE CONDITIONS
Graphic logs of the subsurface conditions encountered at the site are shown on Figures 2,
3 and 5. The subsoils, below about %Z foot of topsoil, consist of up to about 15 feet of
sandy silt and silty clay in the central to eastern part and up to about 6 feet of silty sand
with gravel in the western part, overlying dense, silty sandy gravel and cobbles with
boulders. Drilling in the dense river gravel soils with auger equipment was difficult due
to the cobbles and probable boulders and drilling refusal was encountered in the deposit.
Laboratory testing performed on samples obtained from the borings included natural
moisture content and density, gradation analyses, liquid and plastic limits and unconfined
compressive strength. Results of swell -consolidation testing performed on relatively
undisturbed drive samples of the silty clay soils, presented on Figures 6 and 7, indicate
low to moderate compressibility under conditions of loading and wetting. Results of
gradation analyses performed on small diameter drive samples (minus 1!.'i inch fraction)
of the natural granular soils are shown on Figures 8 through 10. The Iiquid and plastic
limits testing indicate the soils have low or no plasticity and the unconfined compressive
strength tests indicate the silt and clay soils generally have medium stiff consistency. The
laboratory testing is summarized in Table 1.
No free water was encountered in the borings or pits. The granular soils were slightly
moist and the silt and clay soils were very moist. The percolation test results are
presented in Table 2 and indicate infiltration rates between 30 and 60 minutes per inch for
the upper fine-grained soils. The results of a USDA gradation test performed on a sample
of the silt taken at the proposed septic disposal area are presented on Figure 11.
Job No. 115 023A Gecstech
5
FOUNDATION BEARING CONDITIONS
The soils encountered across the project site are variable in type, depth and engineering
properties. The silt and clay soils encountered in the middle to northeastern part of the
site at shallow depth are compressible under loading but appear suitable for support of
lightly loaded spread footings with low bearing capacity. The granular soils encountered
near existing ground surface from roughly the middle of the building site and extending to
the southwest have relatively low settlement potential with moderate bearing capacity.
The silt and clay soils are also a poor subgrade for pavement section support. A coarse
grained structural material should be used to improve the bearing capacity below footings
and as a subbase layer below the pavement section in silt and clay soil areas. A deep
foundation which extends down to the dense river gravel deposit could be used to achieve
a low settlement risk foundation. Presented below are recommendations for shallow
spread footings. If a deep foundation is considered for building support, we should be
contacted for additional analysis and recommendations.
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 compacted fill soils or natural granular soils.
The design and construction criteria presented below should be observed for a spread
footing foundation system.
1) Footings placed on compacted fill soils or the natural granular soils should
be designed for an allowable bearing pressure of 2,000 psf. Based on
experience, we expect settlement of footings designed and constructed as
discussed in this section will be about 1 inch or less and could be
differential due to the variable bearing conditions. There could be some
additional differential settlement if the bearing soils become wet.
Job No. 115 023A
-6-
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.
4) Continuous foundation walls should be 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 lateral earth pressures as discussed in the "Foundation
and Retaining Walls" section of this report.
5) The topsoil, silt and clay soil to the prescribed depth and loose or disturbed
soils should be removed and the footing bearing level extended down to
firm soils. The exposed soils in footing area should then be moisture
adjusted to near optimum and compacted. In silt and clay soil areas, the
exposed soils should be sub -excavated to provide at least 2 feet of
compacted structural fill, such as CDOT Class 2 base course or similar
granular material, below footing bearing grade. Compaction should be to
at least 98°O of standard Proctor density at near optimum moisture content.
The structural fill should extend beyond the footing edges a distance of at
least !°z the depth of fill below the footing.
6) The proposed water storage tank located between Borings 3 and 4 is
expected to be cut into silt and clay soils. The subgrade below the water
storage tank should be improved by placing at least 2 feet of structural fill
similar to that described above in item 5 before placing base course
material for the tank support.
7) Site Class C of IBC 2009, Table 1613.5.2 can be used in the seismic
analysis of the structure.
8) A representative of the geotechnical engineer should observe all footing
excavations prior to concrete placement to evaluate bearing conditions and
test compaction of the structural fill.
Job No. 115 023A
GecDtech
-7 -
FOUNDATION 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 Ieast 55 pcf
for backfill consisting of the on-site soils. Cantilevered retaining structures which are
separate from the building (such as site walls) 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 Ieast 45 pcf for
backfill consisting of the on-site soils.
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.
Backfill should be placed in uniform lifts and compacted to at least 90% o 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 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 0.30 for the silt and clay soils and 0.5 for
the coarse granular soils. Passive pressure of compacted backfill against the sides of the
footings can be calculated using an equivalent fluid unit weight of 300 pcf. The
coefficient of friction and passive pressure values recommended above assume ultimate
Job No. 115023A Gastech
-8 -
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 95% of the maximum standard Proctor density at a moisture content near
optimum.
FLOOR SLABS
The on-site soils, exclusive of topsoil, appear suitable to support the proposed slab -on -
grade construction. There could be some differential settlement due to the variable soil
conditions, mainly the silt and clay soils. We recommend at least 2 feet of granular
structural fill, similar to that recommended below footings, be placed below floor slabs to
help mitigate the settlement risk. 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 relatively well graded sand and gravel should be
placed beneath interior slabs for subgrade support and to break capillary moisture rise.
This material should consist of minus 2 inch aggregate with at least 50% retained on the
No. 4 sieve and less than 12% passing the No. 200 sieve.
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
should consist of granular soils devoid of vegetation, topsoil and oversized rock.
UNDERDRAIN SYSTEM
Although free water was not encountered in the exploratory borings and pits, it has been
our experience in the area and with shallow clay soils 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, be protected from wetting and hydrostatic pressure
buildup by an underdrain system.
Job No. 115 023A
Gertech
-9
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 or drywell based in the
underlying coarse granular soils. 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 11/2 feet deep.
SITE GRADING
The risk of construction -induced slope instability at the site appears low provided the
building is located in the flat part of the site as planned and cut and fill depths are Iimited,
such as at the perimeter areas of the project site. We assume cut and fill depths for
foundations, walls and pavement areas will not exceed about 5 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 slopes that exceed
20% grade.
PAVEMENT SECTION
Asphalt surfaced driveway and parking areas are proposed for the project. Concrete
pavement will also be used in apron areas against the building and in the depressed truck
dock ramp. ESAL traffic loadings for the pavement areas provided to us consist of 143 in
parking areas, 92,652 at the entrance drive and 92,509 at the yard areas/entrance drive
which include the various truck traffic. The subgrade soils encountered at the site are
generally low plasticity sandy silt and clay which are considered a relatively poor support
for pavement sections. Structural fill will be needed for the pavement construction in
some areas. The imported soils should be a granular material with a minimum Hveem
stabilometer 'R' value of 30. Based on the traffic loadings provided, the silt and clay
subgrade condition and our experience with similar projects, we recommend the
Job No. 1 l5 023A
Gec-tech
-10 -
minimum pavement section for passenger vehicle only areas consist of 3 inches of asphalt
over 4 inches of base course on 8 inches of granular subbase. In the entrance drive and
yard areas which include heavy truck traffic, 4 inches of asphalt over 6 inches of base
course on 12 inches of granular subbase is recommended. The concrete pavement in the
aprons next to the building and in the dock ramp should consist of at Ieast 6 inches of
Portland cement concrete over 4 inches of road base on 12 inches of granular subbase.
The asphalt should be a batched hot mix, approved by the engineer and placed and
compacted to the project specifications. The base course and subbase should meet CDOT
Class 6 and Class 2 specifications, respectively. All base course, subbase and required
subgrade fill should be compacted to at least 95c.% of the maximum standard Proctor
density at a moisture content within 2% of optimum. The section thicknesses assume
structural coefficients of 0.14 for aggregate base course, 0.10 for aggregate subbase, 0.44
for asphalt surface and design strength of 4,500 psi for Portland cement concrete. The
material properties and compaction should be in accordance with the project
specifications.
Required fill to establish design subgrade level should consist of imported granular soils.
Prior to fill placement the subgrade should be stripped of vegetation and topsoil, scarified
to a depth of 8 inches, adjusted to near optimum moisture content and compacted to at
least 95% of standard Proctor density. In soft or wet areas a geogrid and/or
subexcavation and replacement with aggregate base soils may be needed for stabilization.
The subgrade should be proofrolled. Areas that deflect excessively should be corrected
before placing pavement materials. The subgrade improvements and placement and
compaction of base and asphalt materials should be monitored on a regular basis by a
representative of the geotechnical engineer.
SURFACE DRAINAGE
The following drainage precautions should be observed during construction and
maintained at all times after the facilities have been completed:
1) Inundation of the foundation excavations and underslab areas should be
avoided during construction.
Job No. 115 023A Gtech
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°'0 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 6 inches in the first 10 feet in unpaved
areas and a minimum slope of 2't2 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 fine-grained soils to reduce surface water
infiltration.
4) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
5) Landscaping which requires regular heavy irrigation should be located at
least 5 feet from foundation walls.
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 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 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.
Job No. 115023A
~Ptech
- 12 -
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,
HEPWORTH - PAWLAK GEOTECHNICAL, INC.
Steven L. Pawlak, P.E.
Reviewed by:
Daniel E. Hardin, P.E.
SLPiksw
cc: M. Design Fusion, LLC - Michael Fa (mfa u.desw fusion.biz)
High Country Engineering -- Roger Neal (rneal(a.;hceng.com)
Job No. 115 023A Gtech
APPROXIMATE SCALE
1"=80'
f
115 023A
GecPtech
HEPwoRTH•PAwtAK GEorEcHnicAL
LOCATION OF EXPLORATORY
BORINGS AND PITS
Figure 1
Elevation - Feet
Elevation - Feet
BORING 1
ELEV. = 5949'
BORING 2
ELEV. = 5949
BORING 3
ELEV. = 5952
- 5955 5955
5950
5945
- 5940
APPROXIMATE PROPOSED DRIVEWAY GRADE
31/12
WC=5.8
5/12 DD=100
-200=52
LL=26
9/12 PI=4
WC=6.9
+4=24
-200=49
21/12
WC =3.4
+4=26
-200: 44
1316,50.+2
... 6/12
/
WC= 117
DD -103
-200=75
=2
LL23
PI=2
i--�
6/12
4/12
WC=22.0
DD=94
-200=91
LL== 25
PI=5
UC 700
3/6,17/6
5950
5945
5940
- 5935 5935
- 5955
- 5950
5945
- 5940
5935
BORING 4
ELEV. = 5953'
T
BORING 5
ELEV. = 5950'
BORING 6
ELEV. = 5950.5'
APPROXIMATE PROPOSED DRIVEWAY GRADE
e -i 4,12 WC=13.4
DD=98
-200=75
�i— 4112 LppL=24
WC=18.18 2
DD=103
-200=82
LL=24
/ PI=4
4112
51/12
6,12
Y. 50/3
WC -17.3
DID =90
-200 91
LL =27
PI= 4
UC = 1,150
Note. Explanation of symbols is shown on Figure 4.
7-;
5/12
5/12
WC=23,6
DD=93
-200=93
LL=27
PI=5
UC=1,200
'/—
6/12
4711
9/12
;/.1 79112
5955
5950
5945
5940
5935
Elevation - Feet
Elevation - Feet
115 023A
H
HEPWORTH-PAWLAK GEOTECHNICAL
LOGS OF EXPLORATORY BORINGS
DRIVEWAY AND PARKING AREAS
Figure 2
Elevation - Feet
Elevation - Feet
- 5950
- 5945
- 5940
- 5935
BORING 7
BORING 8 BORING 9 BORING 10
ELEV. = 5950.5' ELEV. = 5949.5' ELEV. = 5949.5 ELEV. = 5949.5'
50/4
40/6,50/1
WC=3.1
+4=42
-200=19
PROPOSED FLOOR
ELEV. = 5952'
50/1
6/12
'1 WC 20 8
I DD=99
7/12
23/12
50/2
5/12
WC 20
DD --100
J
200 •= 91
UC=2,500
6/12
WC 281
DDS 100
47/12
e4�
50/5
5950
5945
5940
5935
- 5930 5930
- 5950
5945
- 5940
- 5935
BORING 11
ELEV. = 5949'
v
,1 8/12
WC=23.9
DD=96
' 8/12
WC=22.2
D0=100
-200=89
� UC=3,100
91/11
a
a: WC=2.0
+4=60
-200=10
BORING 12
ELEV. = 5950'
15/6,27/6
31/12
57/12
BORING 13
ELEV. = 5949'
7/12
7/12
WC -27 8
DD -92
77/12
50/6
Note: Explanation of symbols is shown on Figure 4.
BORING 14
ELEV. = 5950.5
5950
22/6,50/1
57/12
WCa23
+4 = 45 5945
-200 - 22
5940
5935
Elevation - Feet
Elevation - Feet
115 023A
GecPteCh
HEPWORTH-PAWLAK GEOTECHNICAL
LOGS OF EXPLORATORY BORINGS
BUILDING AREA
Figure 3
LEGEND:
---7
z
31/12
T
NOTES:
TOPSOIL; organic sandy silt and clay, root zone, brown.
CLAY (CL); slightly sandy to sandy, silty, medium stiff to stiff, very moist, red, low to medium plasticity.
SILT AND CLAY (ML -CL); slightly sandy to sandy, medium stiff, very moist, red, low plasticity.
SAND (SM -SC); very silty, slightly clayey, scattered gravel to gravelly, loose to medium dense, slightly moist, red.
GRAVEL AND COBBLES (GM -GP); sillty to slightly silty, sandy, boulders, dense, slightly moist, red -brown,
rounded rock.
Relatively undisturbed drive sample; 2 -inch I.D. California liner sample.
Drive sample; standard penetration test (SPT), 1 3/8 inch I.D. split spoon sample, ASTM D-1586.
Drive sample blow count; indicates that 31 blows of a 140 pound hammer falling 30 inches were
required to drive the California or SPT sampler 12 inches.
Practical drilling refusal.
1. Exploratory borings were drilled on January 27 (Borings 1-6) and February 3 (Borings 7-14), 2015 with 4 -inch
diameter continuous flight power auger.
2. Locations of exploratory borings were measured approximately by pacing from features shown on the site plan
provided.
3. Elevations of exploratory borings were obtained by interpolation between contours shown on the site plan provided
4. The exploratory boring locations and elevations 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 transitions may be gradual.
6. No free water was encountered in the borings at the time of drilling. Fluctuation in water level may occur with time.
7. Laboratory Testing Results:
WC = Water Content (%)
DD = Dry Density (pcf)
+4 - Percent retained on the No. 4 sieve
-200 = Percent passing No. 200 sieve
LL = Liquid L; mit (%)
PI = Plasticity Index (%)
UC = Unconfined Compressive Strength (psf)
115 023A
GelSteCh
HEPWORTH-PAWLAK GEOTECHNICAL
LEGEND AND NOTES
EXPLORATORY BORINGS
Figure 4
Depth - Feet
- 0
- 5
- 10
LEGEND:
—7
00
0-9
_J
PROFILE PIT 1
ELEV.= 5949.5'
/
/
/
GRAVEL- 0
-
i SAND- 26
- SILT.- 55
CLAY=17
PROFILE PIT 2
ELEV. = 5949'
• O
TOPSOIL; organic sandy silt and clay, root zone, brown.
SILT AND CLAY (ML -CL); slightly sandy to sandy, medium stiff, very moist, red, low plasticity.
5
10
GRAVEL AND COBBLES (GM -GP); sillty to slightly silty, sandy, boulders, dense, slightly moist, red -brown,
rounded rock.
Disturbed bulk sample.
NOTES:
1. Exploratory pits were excavated on February 24, 2015 with a Cat 416B backhoe.
2. Locations of exploratory pits were measured approximately by pacing from features shown on the site plan
provided.
3. Elevations of exploratory pits were obtained by interpolation between contours shown on the site plan provided.
4. The exploratory pit locations and elevations should be considered accurate only to the degree implied by the method
used.
5. The lines between materials shown on the exploratory pit logs represent the approximate boundaries between
material types and transitions may be gradual.
6. No free water was encountered in the pits at the time of excavating. Fluctuation in water level may occur with time.
7. Laboratory Testing Results:
Gravel = Percent retained on No. 10 Sieve
Sand = Percent passing No. 10 sieve and retained on No. 325 sieve
Silt = Percent passing No. 325 sieve to particle size .002mm
Clay = Percent smaller then particle size .002mm
Depth - Feet
115 023A
Gech
HEPWORTFHPAWLAK GEOTECHNICAL
LOGS OF EXPLORATORY PITS
Figure 5
Compression °h
Compression
0
1
2
3
4
0
1
2
3
4
5
6
7
Moisture Content = 20.8 percent
Dry Density = 99 pcf
Sample of: Sandy Silty Clay
From: Baring 9 at 2 y2 Feet
— —
Compression
upon
wetting
0.1
.0 10
APPLIED PRESSURE - ksf
Moisture Content = 28.1
Dry Density = 100
Sample of: Sandy Silty Clay
From: Boring 10 at 5 Feet
No movement
upon
wetting
percent
pcf
0.1
1.0 0
APPLIED PRESSURE - ksf
100
115 023A
G grtech
HEPWOHTH•PAWLAK GEOTECHNICAL
SWELL -CONSOLIDATION TEST RESULTS
Figure 6
Compression
Compression
0
1
2
3
4
5
6
0
1
2
3
4
5
Moisture Content = 23.9 percent
Dry Density = 98 pcf
Sample of: Sandy Silty Clay
From: Boring 11 at 2 yz Feet
Compression
upon
wetting
0.1
1.0 10
APPLIED PRESSURE - ksf
Moisture Content = 27.8
Dry Density = 92
Sample of: Sandy Silty Clay
From: Boring 13 at 5 Feet
Compression
upon
wetting
percent
pcf
0.1
1.0 10
APPLIED PRESSURE - ksf
00
0i;
115 023A
Gegtedh
HEPW0RTH•PAWLAK GEOTECHNICAL
SWELL -CONSOLIDATION TEST RESULTS
Figure 7
ti i1; f2[210
HYDROMETER ANALYSIS SIEVE ANALYSIS
TIME READINGS U.S. STANDARD SERIES 1 CLEAR SQUARE OPENINGS
4 1IIN.15HHMIN. 60MIN19MIN.4 MIN. 1 MIN. #200 #100 #50 #30 #16 #8 #4 3/8" 3/4" 1 112' 3' 5'6' 8"
0
10
20
30
40
50
60
70
80
90
100
f
•
{
{-
•
001 ,992 005 .009 019 037 .074 I50 .300 .600 118 2.99 4.75 9.5 12 5 19.0 37.5 76 2 152 203
127
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO SILT
GRAVEL 24 %
LIQUID LIMIT %
SAMPLE OF: Very Silty Clayey Gravelly Sand
SAND
GRAVEL
FINE
MEDIUM 1 COARSE
FINE I COARSE
COBBLES
SAND 27 % SILT AND CLAY 49 %
PLASTICITY INDEX %
FROM: Boring 1 at 5 Feet
too
90
80
U1
7o Z
V7
U3
60 d
So Z
U
40 W
0-
30 30
20
10
0
HYDROMETER ANALYSIS I SIEVE ANALYSIS I
TIME READINGS 1 U S STANDARD SER;ES 1 CLEAR SQUARE OPENINGS
051 1N 15 MIN 60MIN19MIN.4 MIN 1 MIN #200 #100 #50 #30 #16 #8 #4 318" 314' 1 1/2 3` 5°8' 8'
100
I
10
20
30
40
50
60
70
80
90
100
001 .002
•
90
80
0
70 Z
U)
U3
60
1-
50LZL
U
40 Lu
CC
30
20
10
0
.005 .009 .019 037 .074 150 300 .600 1.18 2.36 4.75 9 512 519.0 37.5 76 2 1452 203
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO 51LT
GRAVEL 26 %
LIQUID LIMIT %
SAMPLE OF: Very Silty Clayey Gravelly Sand
SANG
FINE 1 MEDIUM 1 COARIE
GRAVEL
FINE 1 COARSE
SAND 30 % SILT AND CLAY 44 %
PLASTICITY INDEX %
FROM: Boring 2 at 2 yZ Feet
115 023A
Gertech
HEPWORTH•PAWLAH GEOTECHNICAL
GRADATION TEST RESULTS
Figure 8
IMINIOZ1111IMMIZIOI
20E•10t111:IarlIZImoi.'
HYDROMETER ANALYSIS I SIEVE ANALYSIS 1
TIME READ NGS 1 U.S STANDARD SERIES 1 CLEAR SQUARE OPENINGS l
TUN 15 MIN 60MIN19MIN.4 MIN 1 M.N #200 #100 #50 #30 #16 #8 #4 318" 314' 1 112" 3" 5"6' 8°
0
10
20
30
40
50
60
70
80
90
100
90
80
001 .002 005 009 .019 037 074 150 303 000 1 IB 2 30
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO SILT
GRAVEL 42 %
LIQUID LIMIT %
SAMPLE OF: Silty Sandy Gravel
FINE 1
SAND
MED UM 1COARE
4.75 95125 19.0 37.5 702 152 203
Gi1AVEL
FINE I COARSE
127
COBBLES
SAND 39 % SILT AND CLAY 19 %
PLASTICITY INDEX %
FROM: Boring 7 at 4 Feet
70
00
50
40
30
20
10
0
HYDROMETER ANALYSIS I SIEVE ANALYSIS
Ili.
TIME READINGS U.S. STANDARD SERIES 1 CLEAR SQUARE OPENINGS
0 IN. 15 MIN.60MIN19MIN.4 MIN. 1 MIN. #200 #100 #50 #30 #16 #8 #4 3/8" 314" 1 1!2" 3' 5'6" 8"100
1
10
20
30
40
50
60
70
80
90
100
.001 .002 .005 .009 .019 .037 .074 .150 .300 .600 1.18 2.36 4 75 9.512 519.0 37.5 76.2 12152 203
DIAMETER OF PARTICLES IN MILLIMETERS
1
90
ENT PA "MEW
80
70 Z
60 a
F-
50ZU
U
40 CC
a.
30
20
10
0
CLAY 70 50.7
SAND
FINE 1 MEDIUM 1 COARSE
GRAVEL COBBLES
FINE 1 COARSE
GRAVEL 60 %
LIQUID LIMIT %
SAMPLE OF: Slightly Silty Sandy Gravel
SAND 30 % SILT AND CLAY 10 %
PLASTICITY INDEX %
FROM: Boring 11 at 10 Feet
115 023A
Gertech
HEPWORTH-PAWLAK GEOTECHNICAL
GRADATION TEST RESULTS
Figure 9
2-21:14KM:01.1121
HYDROMETER ANALYSIS SIEVE ANALYSIS
4 Mq qq TIME READINGS U S STANDARD SERIES 1 CLEAR SQUARE OPENINGS l
]
0 45 MIN. 15 VAN.60MIN19MIN.4 MIN. 1 MIN. #200 #100 #50 #30 #16 #B #4 3/8' 314" 1 1/2' 3' 5'6' 6" 100
10
20
30
40
50
60
70
80
90
k
1
1
90
80
70
60
50
40
30
20
10
loo 1 o
001 .002 .005 .009 .019 037 074 ,150 300 .600 1.18 2.36 4.75 9.5 19.0 37.5 762 152 203
12.5 127
DIAMETER OF PARTICLES IN MILLIMETERS
CLAY TO &0.T
FW.
SAND
me Dom 1
CRnvEi �g�
FINE 1 COARSE
GRAVEL 45 %
SAND 33 % SILT AND CLAY 22 %
LIQUID LIMIT % PLASTICITY INDEX %
SAMPLE OF: Silty Sandy Gravel FROM: Boring 14 at 4 Feet
115 023A
Gertech
I-IEPWORTH•PAWLAK GEOTECHNICAL
GRADATION TEST RESULTS
Figure 10
RCENT RETAIN !�
HYDROMETER ANALYSIS I SIEVE ANALYSIS I
H� �{q TIME READINGS U.S. STANDARD SERIES 1 CLEAR SQUARE OPENINGS
0 45 MIN 15 MIN.60MIN19MIN,4 MIN.1 MIN. #140 #60 #35 #18 #10 #4 318' 3/4" 1 112" 3" 5'6" 8' 100
24
10
20
30
40
50
60
70
80
90
100
.001 .002 .005 .009 .019
1-
CLAY
SILT
.045 .106 .025 .500 1.00 2 00
DIAMETER OF PARTICLES IN MILLIMETERS
SAND
V. FINE 1 FME 1 MEDIUM !COARSE IY CONSL
90
80
70
60
50
40
30
20
10
0
4.75 9.5 19.0 37.5 76.2 152 203
GRAVEL
SMALL 1 MEDIUM 1 LARGE
COBBLES
115 023A
GRAVEL 0 %
SAND 28 % SILT 55 %
USDA SOIL TYPE: Silt Loam
HEPWORTH'PAWLAK GEOTECHNICAL
CLAY 17 %
FROM: Profile Pit 1 at 3 to 4 Feet
USDA GRADATION TEST RESULTS
:fili+IEIt`-.1121%
Figure 11
HEPWORTH-PAWLAK GEOTECHNICAL, INC.
TABLE 1
SUMMARY OF LABORATORY TEST RESULTS
SAMPLE LOCATION
NATURAL
MOISTURE
CONTENT
(%}
NATURAL
DRY DENSITY
(pcf)
GRADATION
PERCENT
PASSING NO.
200 SIEVE
ATTERBERG LIMITS
UNCONFINED
COMPRESSIVE
STRENGTH
(PSF)
BORING
DEPTH
(ft)
GRAVEL
%`
SAND
{%�
LIQUID LIMIT
(%j
PLASTIC
INDEX
(%)
1
2'/2
5.8
100
52
26
4
5
6.9
24
27
49
2
21/2
3.4
26
30
44
3
2'/
11.7
103
75
23
2
10
22.0
94
91
25
5
700
4
21/2
13.4
98
75
24
2
5
18.8
103
82
24
3
1,700
5
21/2
17.3
90
91
27
4
1,150
6
5
23.6
93
93
27
5
1,200
7
4
3.1
42
39
19
HEPWORTH-PAWLAK GEOTECHNICAL, INC.
TABLE 1
SUMMARY OF LABORATORY TEST RESULTS
SAMPLE LOCATION
NATURAL
MOISTURE
CONTENT
(%)
NATURAL
DRY DENSITY
(pcf}
GRADATION
PERCENT
PASSING NO.
200 SIEVE
ATTERBERG LIMITS
UNCONFINED
COMPRESSIVE
STRENGTH
(PSF)
BORING
DEPTH
(ft)
GRAVEL
(%)
SAND
(%)
LIQUID LIMIT
(%)
PLASTIC
INDEX
(%)
9
21
20.8
99
10
21/2
20.8
100
91
2,500
5
28.1
100
11
21/2
23.9
98
5
22.2
100
89
3,100
10
2.0
60
30
10
13
5
27.8
92
14
4
2.3
45
33
22
HEPWORTH-PAWLAK GEOTECHNICAL, INC.
TABLE 2
PERCOLATION TEST RESULTS
JOB NO. 115 023A
HOLE NO.
HOLE DEPTH
(INCHES)
LENGTH OF
INTERVAL
(MIN)
WATER DEPTH
AT START OF
INTERVAL
(INCHES)
WATER DEPTH
AT END OF
INTERVAL
(INCHES)
DROP IN
WATER LEVEL
(INCHES)
AVERAGE
PERCOLATION
RATE
(MIN./INCH)
P-1
35
15
Water Added
Water Added
6
5
1
30
6%
51/4
%2
5%
51/4
%
6%2
6
%2
6
5'/:
51/2
5
'/
P-2
38
15
Water Added
Water Added
5
41/2
%2
30
5%
5
5
4%2
%2
6
5'/2
'/2
5%:
5
5
4'/2
'/2
P-3
40
15
7
6%
1/2
60
6f2
6%
i
6%
5%
'/2
5'/
51/3
5%2
5%
'/.
5%
5
''4
P-4
38
15
Water Added
6
5%2
%2
45
6
5%
14
5%
51/2
IA
5%2
5
%2
5
4'/=
'/.
4'/
41/2
14
Note: Percolation test holes were hand dug in the bottom of backhoe pits and soaked on February 24,
2015. Percolation tests were conducted on February 25, 2015. The average percolation rates
were based on the last three readings of each test.