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GEOTECHNIGAL ENGINEERING INVESTIGATION
565 FARANHYLL RANCH ROAD
(A.K.A. PARCEL #4, FARANHYLL RANCH)
GARFIELD COUNTY, GOLORADO
Prepared For:
GREEN LINE ARCHITECTS
65 N.4th Street, Suite 5
Carbondale, CO 81623
Project No. GS06 572.000-120
234 Center Drive I Glenwood Springs, Colorado 81601
Telephone: 970-S45-2809 Fax: 970-945-7411
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July 1 ,2021
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TABLE OF CONTENTS
scoPE.........
SUMMARY OF CONCLUSIONS
SITE CONDITIONS
PROPOSED CONSTRUCTION ......,..
GEOLOGY AND GEOLOGIC HAZARDS.............
SUBSURFACE CONDITIONS..........
SITÊ EARTHWORK.....
Excavations
Subexcavation and Structural Fill...-.....,.....
Foundation Wall Backfi11.,................
FOUNDATrONS..............
SLAB-ON.GRADE CONSTRUCTION ...........
CRAWL SPACE CONSTRUCTION..,....,,......
FOUNDATION WALLS
SUBSURFACE DRAINAGE,.,..
SURFACE DRAINAGE
CONCRETE
CONSTRUCTION OBSERVATIONS ......
STRUCTURAL ENGIN EERING SERVICES .
GEOTECHNICAL RISK
LtMITATtONS ....,...........
FIGURE 1-VICINITYMAP
FIGURE 2 _AERIAL PHOTOGRAPH
FIGURE 3 - PROPOSED CONSTRUCTION
FIGURE 4 - SUMMARY LOGS OF EXPLORATORY BORINGS AND PITS
FIGURE 5 - SWELL-CONSOLIDATION TEST RESULTS'
FIGURE 6 - GRADATION TEST RESULTS
FIGURE 7 AND 8 _ FOUNDATION WALL DRAIN CONCEPTS
TABLE I _ SUMMARY OF LABORATORY TESTING
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SCOPE
CTL I Thompson, lnc. has completed a geotechnical engineering investiga-
tion for the property at 565 Faranhyll Ranch Road (a.k.a. Parcel #4, Faranhyll
Ranch) in Garfield County, Colorado. We conducted this investígatÍon to evatuate
subsurface conditions at the site and provide geotechnical engineering recom-
mendations for the proposed construction. The scope of our investigation was set
forth in our Proposal No. GS 21-0186. Our report was prepared from data devel-
oped from our field exploration, laboratory testing, engineering analysis, and our
experience with similar conditions. The report includes a description of subsurface
conditions encountered in our exploratory boring and pits and provides geotech-
nical engineering recommendations for design and construction of the building
foundations, floor systems, below-grade walls, subsurface drainage systems, and
details influenced by the subsoils. A summary of our conclusíons is below.
SUII/IMARY OF CONGLUSIONS
subsurface conditions encountered in our exploratory boring and pits
consísted of about I inches of topsoil and 4.5 to 5.5 feet of sandy
clay, underlain by clayey gravel, cobbles, and boulders. Groundwater
was not found in our exploratory boring and pits at the time of our
subsurface investigation.
Based on geologic mapping and our engineering experience, the
sandy clay and clayey gravel have potential for moderate to high
amounts of consolidation when wetted under building loads. We
judge the residence and ADUlgarage can be constructed on footing
foundations, provided the soils below footings are sub-excavated to
a depth of at least 3 feet and replaced as densely-compacted, struc-
tural fill.
To enhance potential performance of floor slabs in buildings at the
site, we recommend subexcavation of the soils below slabs to a
depth of at least 3 feet and replacement with densely-compacted,
structuralfill.
4.A foundation wall drain should be constructed around the perimeter
of below-grade areas of the buildings to mitigate surface water that
infiltrates backfill soils adjacent to the foundations. Site grading
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should be designed and constructed to rapidly convey surface water
away from the buildings.
SITE COND¡TIONS
The site is located at 565 Faranhyll Ranch Road (a.k.a. Parcel #4, Faranhyll
Ranch) in Garfield County, Colorado. A vicinity map with the site locatíon is includ-
ed as Figure 1. The property is at the base of the east flank of the Grand Hogback.
The lot is an approximately 35-acre parcel that is predominantly west of Faranhyll
Ranch Road. The new buildings are proposed in the west part of the property,
south of an existing residence. An aerial photograph of the west part of the parcel,
including the existing residence is shown on Figure 2. Ground surface in the areas
of the proposed buildings generally slopes down to the northeast at grades visually
estimated at about 10 percent. The subject area of the site is an irrigated hayfield.
A photograph of the proposed building site at the time of our subsurface investiga-
tion is below.
GREEN LINE ARCHNECTS
565 FARANHYLL RANCH ROAD
PROJECT NO. GS06572,000-120
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Looking east across proposed building site
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PROPOSED CONSTRUCTION
Architectural plans for a proposed single-family residence and an
ADU/garage building were being developed at the time of our geotechnical engi-
neering investigation. The residence is anticipated as a one and two-story building
We understand that garage and storage space in the uphill (west) side of the resi-
dence will have a slab-on-grade main level floor with no below-grade areas. The
downhill (east) side of the residence will have a structurally-supported floor with a
crawl space below. Preliminary plans indicate the main level of the ADU/garage
building will be a slab-on-grade. The uphill (west) side of the building will retain
earth. We expect maximum foundation excavation depths of about I to 10 feet.
Foundations loads are likely to be on the order of 1,000 to 3,000 pounds per linear
foot of foundation wall with maximum interior column loads of tess than 75 kips.
We should be provided with architectural plans, as they are further developed, so
we can províde geotechnical/geo-structural engineering input.
GEOLOGY AND GEOLOGIC HAZARDS
we reviewed the geologic map by the colorado Geology survey (cGS), ti-
tled, "Geologic Map of the Cattle Creek Quadrangle, Garfield County, Colorado",
by Kirkham, Streufert, Hemborg, and Stelling (dated 2014). The area of the subject
property is mapped as intermediate debris flow deposits of the Holocene and
Pleistocene Epochs. The sandy clay and clayey gravel soils found in our explora-
tory boring and pits are consistent with the description of the debris flow deposits.
Due to the depositional method, the debrís flow deposits have not been subject to
significant geologic loads. These soils are prone to consolidation when wetted un-
der building loads. We judge the debris flow deposits have potential for moderate
to high amounts of consolidation when wetted under building loads.
We also reviewed the CGS map "Collapsible Soils and Evaporite Karst
Hazard Map of the Roaring Fork Valley, Garfield, Pitkin and Eagle Counties", by
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Jonathan L. White (dated 2002). The surficial soils at the site are mapped as un-
consolidated, which possess potentialfor hydrocompaction when wetted, especial-
ly under building loads. CGS has mapped the approximate location of a historical
occurrence soil settlement on Four Mile Road about 1 mile southeast of the sub-
ject site. Formation of sinkholes is random and can CIccur anywhere and at any
time in the geologic environment at this site and cannot be predícted. The degree
of risk related to sinkholes cannot reasonably be quantified. We did not observe
obvious visual evidence of sinkhole/subsidence formations on or immediately ad-
jacent to the subject property. We are not aware of buildings in the immediate vi-
cinity of the property that have experienced recent subsidence-related damage,
We rate the potential risk of sinkhole development at the site as low.
SUBSURFACE CONDITIONS
Subsurface conditions were investigated by directing drilling of one explora-
tory boring (TH-1) and observing the excavation of two exploratory pits (TP-1 and
TP-2) at the site. The approximate location of the boring and pits are shown on
Figures 2 and 3. Our boring was drilled on May 6,2A21 with soild-stem auger and
a track-mounted drill rig. The pits were excavated on May 21,2021with a track-
hoe. Exploratory drilling and excavation operations were directed by our engineer,
who logged the soils encountered in the boring and pits and obtaíned representa-
tive samples. Graphic logs of the soils encountered in our exploratory boring and
exploratory pits are shown on Figure 4.
Subsurface conditions encountered in our exploratory boring and pits con,
sisted of about I inches of topsoil and 4.5 to 5.5 feet of sandy clay, underlain by
clayey gravet, cobbles, and boulders. Groundwater was not found in our explorato-
ry boring and pits at the time of our subsurface investigation. PVC pipe was in-
stalled in our boring and pits, prior to backfilling, to facilitate subsequent checks of
groundwater. A photograph of conditions exposed in TP-1 is below.
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Conditions exposed in TP-1
Samples of the soíls obtained from our exploratory boring and pits were re-
turned to our laboratory for pertinent testing. One sample of sandy clay selected
for one-dimensional, swell-consolidation testing exhibited 0.3 percent swellwhen
wetted under a load of 1,000 psf. Swell-consolidation test results are shown on
Figure 5. One sample of the clayey gravel selected for gradation analysis con-
tained 29 percent gravel, 32 percent sand, and 39 percent silt and clay (passing
the No. 200 sieve). Gradation test results are not inclusive of rocks larger than 5
inches, whích are present in the in-situ clayey gravel. Gradation test results are
shown on Figure 6. One sample of the sandy clay tested had a water-soluble sul-
fate content of 0.00 percent. Laboratory testing is summarized on Table L
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SITE EARTHWORK
Excavations
Based on our subsurface investigation, we expect excavations for the pro-
posed construction at this síte can be accomplished using conventional, heavy-
duty excavating equipment. Excavations deeper than 5 feet must be braced or
sloped to meet local, state, and federal safety regutations. The sandy clay soílwill
likely classify as Type B soil and the clayey gravel likely classifies as a Type C soil
pursuant to OSHA standards governing excavations. Temporary excavations
should be no steeper than 1 to 1 (horizontal to vertical) in Type B soils and 1,5 to 1
in Type C soils. Contractors are responsible for site safety and providing and
maintaining safe and stable excavations. Contractors should identify the soils en-
countered in excavations and ensure that osHA standards are met.
Free groundwater was not encountered in our exploratory boring and pits at
the time of our subsurface investígation. We do not anticipate excavations to con-
struct the proposed buildings will penetrate a free groundwater table. To mitigate
water from precipitation, excavations should be sloped to gravity discharges or be
directed to temporary surnps where water can be removed by pumping.
Subexcavation d Structural Fill
Based on our field and laboratory data from the site, and our engineering
experience, the sandy clay and clayey gravel (i.e., debris flow deposits) at the site
have potential for moderate to high amounts of consolidation when wetted under
building loads. We judge the residence can be constructed on a footing foundation
with slab-on-grade floors, provided the soils below footings and floor slabs are
sub-excavated to a depth of at least 3 feet and replaced as densely-compacted,
structuralfill. The subexcavation process should extend at least 1 foot beyond the
perimeter of the building footprint. CTL should be called to observe conditions in
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the foundation excavations, príor to placement of structural fill.
The subexcavated soils should be replaced with densely-compaeted,
granular, structuralfill. The soils excavated from the site can be reused as struc-
tural fill, provided they are free of rocks larger than 3 inches in diameter, organic
matter, and debris. lmported structural fill should consist of an aggregate base
course or pit run with a maximum rock size of 3 inches. A sample of desired import
soil should be submitted to our office for approval.
The subexcavated soils, free of organic matter, debris and rocks larger than
3 inches in diameter can be re-used as structuralfill. The structuralfill soils should
be placed in loose lifts of B inches thick or less and moisture-conditioned to within
2 percent of optimum moisture content. Structural fill should be compacted to at
least 98 percent of standard Proctor (ASTM D 698) maximum dry density, Mois-
ture content and density should be checked by a representatíve of our firm during
placement. Observation of the compaction procedure is necessary.
Foundation Wall Backfill
Proper placement and compaction of foundation backfill is important to re-
duce infiltration of surface water and settlement of backfíll. This is especially im-
portant for backfill areas that will support concrete slabs, such as driveways and
patios. The excavated soils free of rocks larger than 4 inches in diameter, organics
and debris can be reused as backfill adjacent to foundation wall exteriors.
Backfill should be placed in loose lifts of approximately 10 inches thick or
less, moisture-conditioned to within 2 percent of optimum moisture content and
compacted. Thickness of lifts will need to be about 6 inches if there are small, con-
fined areas of backfill, which limit the size and weight of compaction equipment.
We recommend backfíll soils be compacted to 95 percent of standard Proctor
(ASTM D 698) maximum dry density. Moisture content and density of the backfill
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should be checked during placement by a representative of our firm. Observation
of the compactíon procedure is necessary.
FOUNDATIONS
Based on geologic mapping and our engineering experience, the sandy
clay and clayey gravel have potential for moderate to high amounts of consolida-
tion when wetted under building loads. We judge the residence and ADU/garage
can be constructed on footing foundations, provided the soils below footings are
sub-excavated to a depth of at least 3 feet and replaced as densely-compacted,
structuralfill. The structural fill should be in accordance with recommendations in
the Subexcavation and Structural Fill section.
Recommended design and construction criteria for footings are below.
These criteria were developed based on our analysis of field and laboratory data,
as well as our engineering experience.
The residence and ADU/garage can be constructed on footing foun-
dations that are supported by an at least 3-feet thickness of densely-
compacted, structural fill. The structuralfill should be in accordance
with recommendations in the subexcavation and structural Fill sec-
tion.
Footings supported by the densely-compacted, structural fill can be
designed for a maximum net allowable soil bearing pressure of 3,000
psf. The weight of backfill soils above the footings can be neglected
for bearing pressure calculation.
A friction factor of 0.40 can be used to calculate resistance to slidÍng
between concrete footings and the structuralfill.
Continuous wall footings should have a minimum wídth of at least 1G
inches. Foundations for isolated columns should have minimum di-
mensions of 24 inches by 24 inches. Larger sizes may be required,
depending upon foundation loads.
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Grade beams and foundation walls should be well reinforced to span
undisclosed loose or soft soil pockets. we recommend reinforcement
sufficient to span an unsupported distance of at least 12 feet.
The soils under exterior footings should be protected from freezing.
We recommend the bottom of footings be constructed at a depth of
at least 36 inches below finished exterior grades for frost protection
The Garfield County building department should be consulted re-
garding required frost protection depth.
SLAB-ON.G RADE CONSTRUCTION
Slab-on-grade floors are planned in parts of the residence and ADU/garage,
To enhance potential performance of floor slabs, we recommend subexcavation of
the soils befow slabs to a depth of at least 3 feet and replacement with densely-
compacted, structuralfill. The structural fill should be in accordance with recom-
mendations in the Subexcavation and Structural Fill section.
Based on our analysis of field and laboratory data, as well as our engineer-
ing experience, we recommend the following precautions for slab-on-grade con-
struction at this site.
Slabs should be separated from footings and columns pads with slip
joints which allow free vertical movement of the slabs.
ïhe use of underslab plumbing should be minimized. Underslab
plumbíng should be pressure tested for leaks before the slabs are
constructed. Plumbing and utilities which pass through slabs should
be isolated from the slabs with sleeves and provided with flexible
couplings to slab supported appliances.
Exterior patio slabs should be isolated from the building. These slabs
should be well-reinforced to function as independent units.
Frequent controf joints should be provided, in accordance with Amer-
ican Concrete lnstitute (ACl) recommendations, to reduce problems
associated with shrinkage and curling.
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CRAWL SPACE CONSTRUCTION
The main level floor in the downhill (east) part of the residence is proposed
as structurally-supported by the foundatíon walls with a crawl space below the floor.
Buílding codes normally require a clear space of at least '18 inches between ex-
posed earth and untreated wood floor components. For non-organic systems, we
recommend a minimum clear space of 12 inches, This minimum clear space should
be maintained between any point on the underside of the floor system (including
beams, plumbing pipes, and floor drain traps and the soils.
Utility connections, including water, gas, air duct, and exhaust stack connec-
tions to appliances on structural floors should be capable of absorbing some deflec-
tion of the floor. Plumbing that passes through the floor should Ídeally be hung from
the underside of the structural floor and not laid on the bottom of the excavation. lt
is prudent to maíntain the minimum clear space below all plumbing fines. lf trench-
ing below the lines is necessaly, wê recommend sloping these trenches, so they
discharge to the foundation drain.
Control of humidity in crawl spaces is important for indoor air quality and
performance of wood floor systems. We believe the best current practices to con-
trol humidity involve the use of a vapor retarder or vapor barrier (10 mil minimum)
placed on the soils below accessible subfloor areas. The vapor retarderlbarrier
should be sealed at joints and attached to concrete foundation elements.
FOUNDATION WALLS
Foundation walls which extend below-grade should be designed for lateral
earth pressures where backfill is not present to about the same extent on both
sides of the wall, such as in basements and crawl spaces. Many factors affect the
values of the design lateral earth pressure on below-grade walls. These factors
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include, but are not limited to, the type, compaction, slope and drainage of the
backfill, and the rigidity of the wall against rotation and deflection.
For a very rigid wall where negligíble or very little deflection will occur, an
"at-rest" lateral eadh pressure should be used in design. For walls that can deflect
or rotate 0.5 to 1 percent of wall height (depending upon the backfill types), lower
lateral earth pressures approaching the "active" condition may be appropriate. Our
experience indicates typical below-grade walls in residences deflect or rotate
slightly unde¡'normal design loads, and that this deflection results in satisfactory
wall performance. Thus, the earth pressures on the walls will likely be between the
"active" and "at-rest" conditions.
For backfill soils conforming with recommendations in the Foundation Wall
Backfill section that are not saturated, we recommend design of below-grade walls
at this site using an equivalent fluid density of at least 45 pcf. This value assumes
some deflection; some minor cracking of walls may occur. lf very little wall deflec-
tion is desired, a higher design value closer to the "at-rest" condition may be ap-
propriate. For the on-site soils, an at-rest lateral earth pressure of 60 pcf is rec-
ommended. These equivalent densities do not include allowances for sloping
backfill, surcharges or hydrostatic pressures.
SUBSURFACE DRAINAGE
Water from precipitation, snowmelt, and irrigation frequently flows through
relatively permeable backfill placed adjacent to a residence and collects on the
surface of less permeable soils at the bottom of foundation excavations. This can
cause wetting of foundation soils, hydrostatíc pressures on below-grade walls and
wet or moist conditíons in below-grade areas, such as basements and crawl spac-
es after construction. To mitigate problems with subsurface water, we recommend
construction of a foundation wall drain around the perimeter of below-grade areas
of the proposed buildings. This includes the ADU/garage wall that will retain earth.
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The foundation wall drains should consist of 4-inch diameter, slotted PVC
pipe encased in free-draining gravel. A prefabricated drainage composite should
be placed adjacent to foundation walls. Care should be taken during backfill opera-
tions to prevent damage to drainage composites. The drains should discharge via
positive gravíty outlets or lead to sumps where water can be removed by pumping.
Gravity outlets should not be susceptible to clogging or freezing. lnstallation of
clean-outs along the draínpipes is recommended. The foundation wall drain con-
cepts are shown on Figures 7 and L
SURFACE DRAINAGE
Surface drainage is critical to the performance of foundations, floor slabs
and concrete flatwork. Site grading should be designed and constructed to rapidly
convey surface water away from the buildings. Proper surface drainage and irriga-
tion practices can help control the amount of surface water that penetrates to
foundation levels and contributes to settlement or heave of soils and bedrock that
support foundations and slabs-on-grade. PositÍve drainage away from the founda-
tions and avoidance of irrigation near the foundations will also help to avoid ex-
cessive wetting of backfill soils, which can lead to increased backfill settlement and
possibly to higher lateral earth pressures, due to increased weight and reduced
strength of the backfill soils. we recommend the following precautions.
The ground surface surrounding the exterior of the buildngs should
be sloped to drain away from the buildings in all directions. We rec-
ommend a minimum constructed slope of at least 12 inches in the
first 10 feet (10 percent) in landscaped areas around the buildings.
2. Backfill around the foundation walls should be moistened and com-
pacted p
section.
ursuant to recommendations in the Foundation Wall Backfill
3.We recommend the buildings be provided with roof gutters and
downspouts. Roof downspouts should discharge well beyond the lim-
its of all backfill. splash blocks and/or extensions should be provided
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at all downspouts so water discharges onto the ground beyond the
backfill. we generally recommend against burial of downspout dis-
charge. Where it is necessary to bury downspout discharge, solid,
rigid pipe should be used, and the pipe should slope to an open
gravity outlet.
Landscaping should be carefully designed and maintained to mini-
mize irrigation. Plants placed close to foundation walls should be lim-
ited to those with low moisture requirements. lrrigated grass should
not be located within 5 feet of the foundation. sprinklers should not
discharge within 5 feet of foundatíons. Plastic sheeting should not be
placed beneath landscaped areas adjacent to foundation walls or
grade beams. Geotextile fabric will inhíbit weed growth yet still allow
natural evaporation to occur.
CONCRETE
Concrete in contact with soil can be subject to sulfate attack. We,measured
a soluble sulfate concentration of 0.00 percent in a sample of soil from the site
(see Table l). For this level of sulfate concentration, ACI 332-08 "Cade Require-
ments for Residentìal Concrete" indicates there are no special cement require-
ments for sulfate resistance in concrete in contact with the subsoils.
ln our experience, superficial damage may occur to the exposed surfaces of
highly permeable concrete, even when sulfate levels are relatively low. To control
this risk and to resist freeze-thaw deterioration, the water-to-cementitious materials
ratio should not exceed 0.50 for concrete in contact with soils that are likely to stay
moist due to surface drainage or high-water tables. Concrete should have a totaf
air content of 6 percent +l- 1.5 percent. We recommend all foundation walls and
grade beams ín contact with the subsoils be damp-proofed.
CONSTRUCTION OBSERVATIONS
We recommend that CTL I Thompson, lnc. be retained to provide construc-
tion observation and materials testing services for the project. This would allow us
the opportunity to verify whether soil condítions are consistent with those found
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during this investigation. lf others perform these observations, they must accept
responsibility to judge whether the recommendations in this report remain appro-
priate. lt is also beneficial to projects, from economíc and practical standpoints,
when there is continuity between engineering consultation and the construction
observation and materials testing phases.
STRUCTURAL ENGINEERING SERVICES
CTL I Thompson, lnc. is a full-service geotechnical, structural, materials,
and environmental engineering firm. Our services include preparation of structural
framing and foundatíon plans. We can also design temporary and permanent earth
retention systems. Based on our experíence, CTL I Thompson, lnc. typically pro-
vides value to projects from schedule and economic standpoints, due to our com-
bined expertise and experience with geotechnical, structural, and materials engi-
neering. We can provide a proposal for structural engineering design services, if
requested.
GEOTECHNICAL RISK
The concept of risk is an important aspect with any geotechnical evaluation
primarify because the methods used to develop geotechnical recommendations do
not comprise an exact science. The analyticaltools which geotechnical engineers
use are generally empirical and must be tempered by engineering judgment and
experience. Therefore, the solutions or recommendations presented in any ge-
otechnical evaluation should not be considered risk-free and, more importantly,
are not a guarantee that the interaction between the soils and the proposed struc-
tures will result in performance as desired or intended. The engineering recom-
mendations in the preceding sectíons constitute our estimate of those measures
necessary to help the buildings perform satisfactorily.
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This report has been prepared for the exclusive use of the client. The infor-
mation, conclusions, and recommendations presented herein are based upon
consideration of many factors including, but not límited to, the type of structures
proposed, the geologic setting, and the subsurface conditions encountered.
Standards of practice continuously change in the area of geotechnical engineer-
ing. The recommendations provided are appropriate for about three years, lf the
proposed project is not constructed within three years, we should be contacted to
determine if we should update this report.
LIMITATIONS
Our exploratory boring and pits provide a reasonable characterization of
subsurface conditions at the site. Variations in the subsurface conditions not índi-
cated by the boring and pits will occur. We should be provided with architectural
plans, as they are further developed, so we can provide geotechnical/geo-
structural engineering input.
This investigation was conducted in a manner consistent with that levelof
care and skill ordinarily exercised by geotechnical engineers currently practicing
under similar conditions in the locality of this project. No warranty, express or im-
plied, is made. lf we can be of fufther service in discussing the contents of this re-
port, please call.
es D. Kellogg,
sion Manager
cTL I THOMPSON,
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GREEN LINE ARCHITECTS
565 FARANHYLL RANCH ROAD
PROJECT NO. cS06s72.000-f 20
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0 1500 3000 NOTE:
SCALET 'l'= 3000'
GBEEN LINE ARCHITECTS
565 Fa¡anMl Rånah Road
PROJËCT NO. GSO6572.OOO-1 20
SATELLITE IMAGE FROM GOOGLE EARTH
(DATED JUNE 2017)
Vicinity
Map
565 Foronhyll Ronch Rood
Flg. 1
LEGEND:
TP_ 1il
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ffiAPPROXIMATE LOCATION OF
EXPLORATORY PIT
APPROXIMATE LOCATION OF
EXPLORATORY BORING
APPROXIMATE LOCATION OF
PROPERTY BOUNDARY
SATELLITE IMAGE FROM GOOGLE EARTH
(DATED JUNE 2017)
0 100 200 NOTE:
SCALE: 1' = 200'
GREEN LINE ARCHÍrECTS
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Aerial
Photograph
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Flg. 2
LEGTND:
TP_1 APPROXIMATEI EXPLoRATORY
I }.i. I APPROXIMATE*$ EXPLORATORY
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LOCATION
PIT
LOCATION
BORING
OF
OF
0 NOTE:
GREEN LINEARCH]TECTS
5€:t Fåtanfry{l Råñch Road
PROJECT NO. GSO6 57 2.OOO-1 20
BASE DRAWING BY GREEN LINE
ARCHTTECTS (DATED APRTL 14, 2021)
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TP_1
TH-1 TP-1
1An2
36/5.5
10
15
GREEN LINEARCHITECTS
565 FAMNHYLL RANCH ROAÞ
CTLIT PROJECT NO. c506572.000-120
Logs of
lt'*t
TP-2
5
0 LEGEND:
TOPSOIL, CLAY, SANDY, SILT, DARK BROWN,
ORGANICS,
CLAY, SANÞY, MEDIUM STIFF, MOIST, BROWN, DARK
BROWN. (CL)
GRAVEL, CLAYEY, SAND, COBBLES, BOULDERS,
MEDIUM DENSE, MOIST, BROWN, GRAY, (GC, SC)
DRIVE SAMPLE. THE SYMBOL 1O/l2INDICATES 1O
BLOWS OF AN AUTOMATIC 14o-POUND HAMMER
FALLING 30 INCHES WERE REQUIRED TO DRIVE A
2.5-INCH O.D. CALIFORNIA-BARREL SAMPLER 12
INCHES.
INDICATES BULK SAMPLE FROM EXCAVATED SOILS
PRACTICAL SOLID-STEM AUGER REFUSAL ON
COBBLES AND BOULDERS.
NOTES:
EXPLORATORY BORING WAS DRILLED ON MAY 6, 2021
WITH 4jNCH DIAMETER, SOLID-STEM AUGER AND A
TRACK,Ii¡OUNTED DRILL RIG. THE BORING WAS
BACKFILLED IMMEDIATELY AFTER EXPLORATORY
DRILLING OPREATIONS WERE COMPLETED.
2. EXPLORATORY PITS WERE EXCAVATED ON MAY 2I,
2021 WITH A TRACKHOE. THE PITS WERE BACKFILLED
IMMEDIATELY AFTER EXPLORATORY EXCAVATION
OPERATIONS WERE COMPLETED.
3. GROUNDWATER WAS NOT FOUND IN EXPLORATORY
BORING OR PITS AT THE TIME OF DRILLING AND
EXCAVATION. PVC PIPE WAS INSTALLED IN OUR
BORING AND PITS, PRIOR TO BACKFILLING, TO
FACILITATE SUBSEQUENT CHECKS OF
GROUNDWATER.
4. LOCATIONS OF OUR EXPLORATORY BORING AND PITS
ARE APPROXIMATE.
5. THËSE LOGS ARE SUBJECT TO THE EXPLANATIONS,
LIMITATIONS, AND CONCLUSIONS CONTAINED IN THIS
REPORT.
Þtrll¡lu-
IFo-
UJo
t-r!tuIL
Tt:IL
lrJo
10
15
þ
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T
Summarv
Explorató
Boiing an
FIG.4
ffi
1
6
4
3
2
0
-2
-3
fi-+
anz
O- -çX"tu
sz^O-o6
U'luÉ.-
ù-t
Eoo
-8
0.1
APPLIED PRESSURE . KSF
Somple of CLAY, SANDY (CL)
10
DRY UNIT WEIGHT=
MOISTURE CONTENT=
109
19.4
Swell-Consolidation
Test Results
100
PCF
%From TH-,I AÏ 4 FEET
GREEN LINE ARCHITECTS
565 FARANHYLL RANCH ROAD
PROJECT NO. GS06572.000-120
k
| ||
EXPANSION UNDER CONSTANT
PRESSURE DUE TO WETTINGllll l t|lltt\
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)
1.0
FIG.5
ffi
SANDS GRAVELCLAY (PtASTtC) TO SttT (NoN-pt_AsTtÇ)
FINE MED'UM COARS FINE COARSE COBBLÉS
ANALYSIS SIEVE
_*_t__t_
-l_.__¡;
__t
-t-+_._
__t__.--'-
t-È-_-
-_t*-
-
_t *,_-___|-:
-:=
_-t___t_=---_-_444
.1-_1____t--_t_
-|-i-
------]_-----------f------
-t_-___,.-
-,_-1.-
-*--l--l--
0
10
?0
30
40
50
60
70
60
90
'100
oUz
þ
rlJdt-z
LIJ
d.u
,4
90
80
100
.001 0_002 .005 .009 .019 .037 ,074 .149
DIAMETER OF PARTICLE IN MILLIMETERS
u.s.
5'6" ß"
SERIES
.16 '10 .8
CLÊAR SOUARE OPENINGS
3t8" 3t4" 'tyi' 3'
30
20
10
0 .297 ,590
0.42
25 HRi 7 HR.
45 MtN. 15 MtN.
1.19 ?.o 2.38 4.76 e.s2 19..t 36..1 76.2 121si!oo
60 MtN. 19 MtN. 4 MtN. I MtN. .200 .100 .50 .40 .30
Somple of snxo, cLAyEy (Sc)From TP - 1 AT 8-9 FEET
GRAVEL
SILT E CLAY
PLASTICITY INDEX
GRAVEL
SILT & CLAY
PLASTICITY INDEX
SAND
l-¡ouro t-t¡¡tt
29
be
%
%
32%
a/o
o/o
Somple of
From
GREEN LINE ARCHITECTS
565 FARANHYLL RANCH ROAD
PROJECT NO. GS06572.000-1 20
% SANDo/o LIQUID LIMIT
o/o
otfo
Yo
Gradation
Test Results
SANDS GRAVELCLAY (PI-AST|C) TO StLT (NON-PLAST|C)
FINE MEDIUM COARS FINE COARSE COBBLES
SIEVE
--.__-..t-___.t_t__
-------+---------"-t-__t__ _-_,_t--=-
.-t__.
---_-.-f-
-l-
__t_
_t--_
.. __t_
otozıØ
ff60Fz
ö50É.
uJ9o
30
20
1o
0
DIAMETER OF PARTICLE IN MILLIMETERS
Fzl!
t¡I
27 2A0
152
90
80
100
10
20
30
40
50
60
7A
80
90
100.00t 0.002 ,005 .009 .019 .037 .074 .l4S 1.19 2.0 2.38 4.76 9.32 19.1 36,1 76.2 1
RÊAÞINGS U.S, STANDARD SERIES
'100 '50'40 '30 .16 .10 '8
CLEAR SQUARE OPENINGS
318" 314" 1yi' 3' 5'6"
.297 .590
0.4?
60 MtN. t9 MtN. 4 MtN. 1 MtN, .200
25 HR. 7 HR,
45 MtN. 15 MtN.
FIG.6
ffi
2-3'
**¡OSIJA
COIER E}-ITIRE HDTT{ OF
BELOW-GMDE ITAIL
SUP JOINT
DRAI].¡{GE
coMPosm
(M|RADRA¡N 6000
oR Eau¡vAt_EM)
ATTACH PLASNC SHEENNG
TO FOUNDATION
E'MINIMUM
OR BEYOND
GRAVEL WITH NON-WOIEN
GEOtÐfir-E FABRTC (Umnn
140N OR EOUVAUUI).
I:1 SLOPE FROM
BOTTOM OF FOOTNG
(rvHtcHEvER ts GREATER)
1:lNgH DTAMEIER PERFORATED RtctD DRATN ptpE
THE ptpE sHour.D BE p¡âcED lN ¡ rns{CH *mi
A,SLOPE OF AT IEAST I¿I8-INCH DROP PER
FOOT OF DRAIN.
ENCÁSE ptpE tN 1/2. TO 1-1/2. SCREENED
cRAvEL ÐcEND cRAvEL urEillrv ro FooTtNc
AND AT tEASr 1/2 HAø{r OF FOOT|NG. Rtt
EÌ\MRE TRENCH W¡N{ GRA\ÆL
NOTE:
IHE_BOTTOM OF Tt{E DRATN SHOULD BE ÂT tsAsf 2 tNcHES BELOTV BOTTOM OF
EggIlNG AT THE HtGHEsr potul Ar.¡D slopE_Dotvir¡¡vARit-ïo n Fosirn-€-ô¡väiffOUI1EÍ OR TO A SUMP TYHERE IYAIER CNN gr NN¡OIAO'FÍ 'PUUCÑd
GREEN LINEARCHITECTS
A85 FARANFÍYI-LRANCH ROAD
PROJECT NO. GSO6572.OOO-1 20
Foundation
Wall Drain
Goncept Êla a
ffi
SLOPE
OSHA
COIÆR ENNRE WDTT{ OF
DRAltl¡AcE
COMPOSIIE
(MIRADRA|N 60(x)
oR EQuMA|"E}{T)
ATTACH PI..ASflC SHEENNC
TO FOUNDAIION IYAI.I
SLOPE FROM
CRAWL s}¡çE -/PER
GRAIEL IYÍTH NON-ITOIEN
GEOTÐfltE FABRIC (MIRAFI
l,+ON OR EAUVATENÐ.RECOMME}IDED
vnpoR BARRIER
MINIMUM
BETOND
gt
OR
1:f
ENC,ASE PIPE IN
GRA\EL ÐfiEND
AT.ID AT TEAST
E}{TIRE TRENCH
GREEN L¡NEARCH]rECTS
665 FARANI-ÍYLL RANCH ROAD
BOTTOM OF FOONNG
(TYH|CHEVER tS GREATER)
_4:lNcH DtA¡rnER PERFORATED DRATN PtpE THEPIPE SI{OUI,.D BE PI.ACED IN A TRENCH W[M-A-
çLOtsE OF AT |-EAST t/8-tNCH DROP pER FOOTOF DRA¡N.
1/2'TO 1-1/2'.SCREENED
GRAVET I.ATERAI..LY TO FOOTNG1/2 HAGfiÍ OF FOOrNc. RtL
IVIÍH GRAIÆL
NOTE:
P¡ryry qïgvlD BE AMAsr 2 NcHEs BELoTT BoTToM oF FoonNc ÆTHE HIOHEST PONr AND SLOPE DOIVNWARD-iOï POöirrI'L 'GAÃ'üffi "'
oullEr oR T0 A suMp tïFtERE WATER CÂr.t BE Rn¡ó'Éb-Br'pùuÞwa.
Foundation
Wall Drain
Concept
STRUCruRAL FLOOR
PROJECT NO. GSO6572.OOO-1 20 Flo.8
TABLE ISUMMARY OF LABORATORY TESTINGPROJECT NO. cS06572.000-120ffiDÊSCRIPTIONSANDYCLAY. SANDY (CL)SAND, CLAYEY (SC)CLAY, SANDY (CL)CLAY, SANDY (CL)PASSINGNO.200SIEVEloÄ\772086PERCENTSAND(o/o\32PERCENTGRAVEL(o/o)29SOLUBLESULFATES(o/o\0.00-SWELL(o/ol0.3APLASTICITYINDEX(%\LIOUIDLIMIT(o/o\DRYDENSITY(PCF)109MOISTURECONTENT(%\19.4DEPTHIFËËT)45-68-94-57-8EXPLORATORYBORING AND PITTH-1TP.1TP-,ITP.2TP-?. SWELL MEASURED WITH lOOO PSF APPLIED PRESSURE.NEGATIVE VALUE INDICATES COMPRESSION.Page I of I