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GEOTECHNICAL INVESTIGATION
PROPOSED COMMERCIAL/INDUSTRIAL
BUILDING
SEC Slover Avenue and Catawba Avenue
Fontana, California
for
Seefried Industrial Properties, Inc.
22885 Savi Ranch Parkway Suite E Yorba Linda California 92887
voice: (714) 685-1115 fax: (714) 685-1118 www.socalgeo.com
February 16, 2022
Seefried Industrial Properties, Inc.
2321 Rosecrans Avenue, Suite 2220
El Segundo, California 90245
Attention: Mr. Dan Bick
Senior Vice President
Project No.: 19G241-3
Subject: Geotechnical Investigation
Proposed Commercial/Industrial Building
SEC Slover Avenue and Catawba Avenue
Fontana, California
Gentlemen:
In accordance with your request, we have conducted a geotechnical investigation at the subject
site. We are pleased to present this report summarizing the conclusions and recommendations
developed from our investigation.
We sincerely appreciate the opportunity to be of service on this project. We look forward to
providing additional consulting services during the course of the project. If we may be of further
assistance in any manner, please contact our office.
Respectfully Submitted,
SOUTHERN CALIFORNIA GEOTECHNICAL, INC.
Pablo Montes Jr.
Project Engineer
Robert G. Trazo, GE 2655
Principal Engineer
Distribution: (1) Addressee
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
TABLE OF CONTENTS
1.0 EXECUTIVE SUMMARY 1
2.0 SCOPE OF SERVICES 3
3.0 SITE AND PROJECT DESCRIPTION 4
3.1 Site Conditions 4
3.2 Proposed Development 4
3.3 Previous Study 5
4.0 SUBSURFACE EXPLORATION 7
4.1 Scope of Exploration/Sampling Methods 7
4.2 Geotechnical Conditions 7
5.0 LABORATORY TESTING 9
6.0 CONCLUSIONS AND RECOMMENDATIONS 11
6.1 Seismic Design Considerations 11
6.2 Geotechnical Design Considerations 13
6.3 Site Grading Recommendations 15
6.4 Construction Considerations 18
6.5 Foundation Design and Construction 19
6.6 Floor Slab Design and Construction 20
6.7 Retaining Wall Design and Construction 21
6.8 Pavement Design Parameters 23
7.0 GENERAL COMMENTS 26
APPENDICES
A Plate 1: Site Location Map
Plate 2: Boring Location Plan
B Boring Logs
C Laboratory Test Results
D Grading Guide Specifications
E Seismic Design Parameters
F Excerpts from Previous Study
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 1
1.0 EXECUTIVE SUMMARY
Presented below is a brief summary of the conclusions and recommendations of this investigation.
Since this summary is not all inclusive, it should be read in complete context with the entire
report.
Site Preparation Recommendations
• Demolition of the existing structure, including foundations, floor slab, pavements, concrete
flatwork, septic tanks and any subsurface improvements which will not be utilized as part of
the new development, will be required. Debris resulting from demolition activities should be
disposed of off-site in accordance with local regulations. Alternatively, concrete and asphalt
debris may be crushed to a maximum 2-inch particle size, mixed with the on-site soils, and
reused as compacted structural fill.
• Minor stripping of the existing vegetation will be required within the planter areas. Removal
of trees should include the root masses, with the resulting excavation being backfilled with
compacted structural fill. These materials should be properly disposed of off-site.
• The subsurface conditions encountered at the boring locations generally consist of a surficial
layer of fill soils underlain by native alluvium. The fill soils extend to depths of 2½ to 6½±
feet at the boring locations. No documentation regarding the placement or compaction of the
fill soils is available, and they are therefore considered to represent undocumented fill. These
soils are not considered suitable to support the foundation loads of the new structure.
• Remedial grading is recommended within the proposed building area in order to remove the
existing undocumented fill soils, in their entirety. It is also recommended that the proposed
building pad area be overexcavated to a depth of at least 5 feet below existing grade and to
a depth of at least 3 feet below proposed pad grade, whichever is deeper. Overexcavation
within the new foundation areas is recommended to extend to a depth of at least 3 feet below
proposed foundation bearing grade.
• Additional soils classified as possible fill were encountered at some of the boring locations,
extending to depths of 4½ to 9½± feet. The possible fill soils should be further evaluated at
the time of rough grading. If they are determined to consist of artificial fill soils, they should
be overexcavated in their entirety. In addition, three (3) isolated areas of possible abandoned
storage tanks were identified during our previous investigation. These areas may require
additional overexcavation at the time of grading.
• After overexcavation has been completed, the resulting subgrade soils should be evaluated
by the geotechnical engineer to identify any additional soils that should be overexcavated.
The resulting soils should be scarified and moisture conditioned to achieve a moisture content
of 0 to 4 percent above optimum moisture, to a depth of at least 12 inches. The
overexcavation subgrade soils should then be recompacted under the observation of the
geotechnical engineer. The previously excavated soils may then be replaced as compacted
structural fill.
• The new pavement and flatwork subgrade soils are recommended to be scarified to a depth
of 12± inches, thoroughly moisture conditioned and recompacted to at least 90 percent of
the ASTM D-1557 maximum dry density. An overexcavation may be necessary for new
pavements located in the previous abandoned storage tank areas.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 2
Building Foundation Recommendations
• Spread footing foundations, supported in newly placed structural fill soils.
• Maximum, net allowable soil bearing pressure: 2,500 lbs/ft2.
• Reinforcement consisting of at least two (2) No. 5 rebars (1 top and 1 bottom) in strip footings.
Additional reinforcement may be necessary for structural considerations.
Building Floor Slab Recommendations
• Conventional Slab on Grade, at least 6 inches thick
• Modulus of Subgrade Reaction: k = 150 psi/in
• Reinforcement is not considered to be necessary for geotechnical considerations.
• The actual thickness and reinforcement of the floor slab should be determined by the
structural engineer
Pavements
ASPHALT PAVEMENTS (R = 50)
Materials
Thickness (inches)
Parking
Stalls
(TI = 4.0)
Auto Drive
Lanes
(TI = 5.0)
Truck Traffic
(TI = 6.0) (TI = 7.0) (TI = 8.0)
Asphalt Concrete 3 3 3½ 4 5
Aggregate Base 3 3 4 5 5
Compacted Subgrade 12 12 12 12 12
PORTLAND CEMENT CONCRETE PAVEMENTS (R = 50)
Materials
Thickness (inches)
Automobile
Parking and
Drive Areas
(TI=4.0 & 5.0)
Truck Traffic
(TI =6.0) (TI =7.0) (TI =8.0)
PCC 5 5 5½ 6½
Compacted Subgrade
(95% minimum compaction) 12 12 12 12
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 3
2.0 SCOPE OF SERVICES
The scope of services performed for this project was in accordance with our Change Order No.
19G241-CO, dated December 23, 2021. The scope of services included a visual site
reconnaissance, subsurface exploration, field and laboratory testing, and geotechnical
engineering analysis to provide criteria for preparing the design of the building foundations,
building floor slab, and parking lot pavements along with site preparation recommendations and
construction considerations for the proposed development. The evaluation of the environmental
aspects of this site was beyond the scope of services for this geotechnical investigation.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 4
3.0 SITE AND PROJECT DESCRIPTION
3.1 Site Conditions
The subject site is located at the southeast corner of Slover Avenue and Catawba Avenue in
Fontana, California. The site is bounded to the north by Slover Avenue, to the west by Catawba
Avenue, to the south by single-family residences, and to the east by Citrus Avenue. The general
location of the site is illustrated on the Site Location Map, enclosed as Plate 1 in Appendix A of
this report.
The site is a rectangular-shaped property, totaling 17.41± acres in size. The site is comprised of
several contiguous parcels which include residential lots and one large commercial lot. The west
and central regions of the site is developed with a commercial lot, which includes a warehouse
60,000± ft² in size. The building is a single-story structure of concrete tilt-up construction,
presumably supported on conventional shallow foundations with a concrete slab-on-grade floor.
The building is surrounded by asphaltic concrete and Portland cement concrete pavements. The
majority of the pavements at the site are in fair condition, however, isolated areas of pavement
distress were observed in the southern and southeastern regions of the site. The remainder of
the site located to the east is developed with residential lots. The existing residences are generally
single-story structures of wood-frame construction, presumably supported on conventional
shallow foundations, with slab-on-grade floors. Ground surface cover within the residential lots
consists of exposed soils, with some landscaping, and limited areas of concrete pavements.
Detailed topographic information was not available at the time of this report. Based on visual
observations made at the time of the subsurface investigation and from elevations obtained from
Google Earth, the overall site topography generally slopes downward to the southwest at a
gradient of 1.5± percent.
3.2 Proposed Development
Our office was provided a conceptual site plan identified as Scheme 1, prepared by HPA, dated
December 16, 2019. Based on this plan, the site will be developed with one (1) new
commercial/industrial building located in the central region of the site. The new building will be
442,790± ft² in size and will be constructed with dock-high doors along a portion of the south
building wall. The building will be surrounded by asphaltic concrete pavements in the parking and
drive lanes, Portland cement concrete pavements in the loading dock area, with concrete flatwork
and landscape planters throughout.
Detailed structural information has not been provided. It is assumed that the new building will be
a single-story structure of tilt-up concrete construction, typically supported on a conventional
shallow foundation system with concrete slab-on-grade floors. Based on the assumed
construction, maximum column and wall loads are expected to be on the order of 100 kips and 3
to 5 kips per linear foot, respectively.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 5
No significant amounts of below-grade construction, such as basements or crawl spaces, are
expected to be included in the proposed development. Based on the assumed topography, cuts
and fills of 2 to 3± feet are expected to be necessary to achieve the proposed site grades.
3.3 Previous Study
Southern California Geotechnical, Inc. (SCG) previously conducted a geotechnical investigation
that included the subject site. The previous report is identified as follows:
Geotechnical Investigation, Proposed Commercial/Industrial Building, SEC Slover Avenue
and Catawba Avenue, Fontana, California, prepared by Southern California Geotechnical,
Inc. (SCG) for Seefried Industrial Properties, Inc., SCG Project No. 19G241-1, dated
January 15, 2020 (DRAFT).
Asphaltic concrete pavements were present at the ground surface at four (4) of the boring
locations, generally located in the eastern region of the site. At these locations, the pavement
sections consist of 2 to 3± inches of asphaltic concrete, underlain by 4 to 5± inches of aggregate
base. Ground surface cover within the western region of the site consisted of a surficial layer of
aggregate base. Artificial fill soils were encountered beneath the pavements and aggregate base
at most of the boring locations, extending to depths of 2½ to 6½± feet below the existing site
grades. The fill soils generally consist of loose to dense silty fine sands and fine to coarse sands
with varying silt content. The fill soils possess a disturbed, mottled appearance, resulting in their
classification as artificial fill. Additional soils classified as possible fill were encountered beneath
the fill soils at Boring Nos. B-2 and B-7, extending to depths of 4½ and 9½± feet below the
existing site grades. The possible fill generally consists of medium dense to dense silty fine to
medium sands and fine to coarse sands with varying silt and gravel content. These soils resemble
the composition of the underlying alluvium, but possess a somewhat disturbed appearance,
resulting in their classification as possible fill. Native alluvium was encountered beneath the
artificial fill soils, possible fill soils, or below the pavements, at all of the boring locations,
extending to at least the maximum depth explored of 25± feet below existing site grades. The
alluvial soils generally consist of medium dense to dense gravelly fine to coarse sands, with some
layers of loose to medium dense silty fine sands and sandy silts.
At the time of the referenced investigation, SCG observed several isolated areas of pavement
distress, or possibly subsidence, in the south and southeast regions of the site. The areas of
distress which were observed during our site exploration consisted of three (3) separate areas,
which are identified in the enclosed Boring Location Plan, Plate 2. These areas of distress were
identified by the on-site manager at the time of our site exploration. Areas 1 and 2 are located in
the trailer parking stalls located in the southeastern region of the property. The depressions in
these areas are generally rectangular-shaped, extending 7 to 8 inches deep. Within areas 1 and
2, there was severe cracking of the asphaltic concrete pavements. The pavement cracks were 2
to 3 inches thick, and up to 18 inches deep. Based on information provided by the on-site
manager, the distressed pavement areas had increased in size within the last 3 years. Area 3 is
located on the southeast side of the existing warehouse. This area is defined by a square-shaped
asphaltic concrete (AC) patch. Based on information provided by the on-site manager, the AC
repair was required due to a 6 to 10-foot-deep depression, which was backfilled and patched.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 6
SCG performed an additional subsurface exploration for the distressed pavement areas described
above. As part of the additional study, SCG advanced eight borings (identified as Boring Nos. B-
10 through B-17) to a depth of 20± feet below the existing site grades. Possible fill soils were
encountered at most of the boring locations, extending from the ground surface, down to depths
of 4½ to 7± feet. The possible fill soils were comprised of loose to medium dense, silty fine sands
with varying medium to coarse sand and fine to coarse gravel content. Below these materials,
the borings encountered medium dense to dense native alluvium, comprised of fine to coarse
sands with varying silt and gravel content. Based on the results of the subsurface exploration, it
was expected that the pavement distress was due to abandoned underground storage tanks
which may have been abandoned and not properly backfilled. No formal report was prepared
following the additional exploration.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 7
4.0 SUBSURFACE EXPLORATION
4.1 Scope of Exploration/Sampling Methods
The subsurface exploration conducted for this project consisted of a total of twenty (20) borings
(identified as Boring Nos. B-1 through B-20) advanced to depths of 10 to 25± feet below the
existing site grades. Boring Nos. B-1 through B-3 were drilled on December 11, 2019. Boring Nos.
B-9 through B-17 were drilled on January 8, 2020. Boring Nos. B-18 through B-20 were drilled on
January 17, 2022. All of the borings were logged during drilling by a member of our staff.
The borings were advanced with hollow-stem augers, by a conventional truck-mounted drilling
rig. Representative bulk and relatively undisturbed soil samples were taken during drilling.
Relatively undisturbed soil samples were taken with a split barrel “California Sampler” containing
a series of one inch long, 2.416± inch diameter brass rings. This sampling method is described
in ASTM Test Method D-3550. In-situ samples were also taken using a 1.4± inch inside diameter
split spoon sampler, in general accordance with ASTM D-1586. Both of these samplers are driven
into the ground with successive blows of a 140-pound weight falling 30 inches. The blow counts
obtained during driving are recorded for further analysis. Bulk samples were collected in plastic
bags to retain their original moisture content. The relatively undisturbed ring samples were placed
in molded plastic sleeves that were then sealed and transported to our laboratory.
The approximate locations of the borings are indicated on the Boring Location Plan, included as
Plate 2 in Appendix A of this report. The Boring Logs, which illustrate the conditions encountered
at the boring locations, as well as the results of some of the laboratory testing, are included in
Appendix B.
4.2 Geotechnical Conditions
Pavements
Asphaltic concrete pavements were present at the ground surface at five (5) of the boring
locations. At these locations, the pavement sections consist of 1 to 3± inches of asphaltic
concrete, underlain by 0 to 5± inches of aggregate base. Ground surface cover within the western
region of the site consisted of a surficial layer of aggregate base.
Artificial Fill
Artificial fill soils were encountered beneath the pavements and aggregate base at most of the
boring locations, extending to depths of 2½ to 6½± feet below the existing site grades. The fill
soils generally consist of loose to dense silty fine sands and fine to coarse sands with varying silt
content. The fill soils possess a disturbed, mottled appearance, resulting in their classification as
artificial fill.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 8
Additional soils classified as possible fill were encountered beneath the fill soils at Boring Nos. B-
2 and B-7, extending to depths of 4½ and 9½± feet below the existing site grades. The possible
fill generally consists of medium dense to dense silty fine to medium sands and fine to coarse
sands with varying silt and gravel content. These soils resemble the composition of the underlying
alluvium, but possess a somewhat disturbed appearance, resulting in their classification as
possible fill.
Alluvium
Native alluvium was encountered beneath the artificial fill soils, possible fill soils, or below the
pavements, at all of the boring locations, extending to at least the maximum depth explored of
25± feet below existing site grades. The alluvial soils generally consist of medium dense to dense
gravelly fine to coarse sands, with some layers of loose to medium dense silty fine sands and
sandy silts.
Groundwater
Free water was not encountered during the drilling of any of the borings. Based on the lack of
any water within the borings, and the moisture contents of the recovered soil samples, the static
groundwater is considered to have existed at a depth in excess of 25± feet at the time of the
subsurface exploration.
As part of our research, we reviewed available groundwater data in order to determine the historic
high groundwater level for the site. Water level data was obtained from the California Department
of Water Resources website, http://www.water.ca.gov/waterdatalibrary/. The nearest monitoring
well is located approximately 700 feet north of the site. Water level readings within this monitoring
well indicates a high groundwater level of 322± feet below the ground surface in April 1995.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 9
5.0 LABORATORY TESTING
The soil samples recovered from the subsurface exploration were returned to our laboratory for
further testing to determine selected physical and engineering properties of the soils. The tests
are briefly discussed below. It should be noted that the test results are specific to the actual
samples tested, and variations could be expected at other locations and depths.
Classification
All recovered soil samples were classified using the Unified Soil Classification System (USCS), in
accordance with ASTM D-2488. Field identifications were then supplemented with additional visual
classifications and/or by laboratory testing. The USCS classifications are shown on the Boring
Logs and are periodically referenced throughout this report.
Density and Moisture Content
The density has been determined for selected relatively undisturbed ring samples. These densities
were determined in general accordance with the method presented in ASTM D-2937. The results
are recorded as dry unit weight in pounds per cubic foot. The moisture contents are determined
in accordance with ASTM D-2216, and are expressed as a percentage of the dry weight. These
test results are presented on the Boring Logs.
Consolidation
Selected soil samples have been tested to determine their consolidation potential, in accordance
with ASTM D-2435. The testing apparatus is designed to accept either natural or remolded
samples in a one-inch high ring, approximately 2.416 inches in diameter. Each sample is then
loaded incrementally in a geometric progression and the resulting deflection is recorded at
selected time intervals. Porous stones are in contact with the top and bottom of the sample to
permit the addition or release of pore water. The samples are typically inundated with water at
an intermediate load to determine their potential for collapse or heave. The results of the
consolidation testing are plotted on Plates C-1 through C-4 in Appendix C of this report. Additional
consolidation tests from the previous geotechnical investigation are included in Appendix F.
Maximum Dry Density and Optimum Moisture Content
A representative bulk sample has been tested for its maximum dry density and optimum moisture
content. The results have been obtained using the Modified Proctor procedure, per ASTM D-1557
and are presented on Plate C-5 in Appendix C of this report. This test is generally used to compare
the in-situ densities of undisturbed field samples, and for later compaction testing. Additional
testing of other soil types or soil mixes may be necessary at a later date. Additional maximum dry
density tests from the previous geotechnical investigation are included in Appendix F.
Soluble Sulfates
Representative samples of the near-surface soils were submitted to a subcontracted analytical
laboratory for determination of soluble sulfate content. Soluble sulfates are naturally present in
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 10
soils, and if the concentration is high enough, can result in degradation of concrete which comes
into contact with these soils. The results of the soluble sulfate testing are presented below, and
are discussed further in a subsequent section of this report.
Sample Identification Soluble Sulfates (%) Sulfate Classification
B-1 @ 0 to 5 feet
(Pervious Study)
0.005 Not Applicable (S0)
B-8 @ 0 to 5 feet
(Previous Study)
0.002 Not Applicable (S0)
B-20 @ 0 to 5 feet <0.001 Not Applicable (S0)
Corrosivity Testing
Representative bulk samples of the near-surface soils were submitted to a subcontracted
corrosion engineering laboratory to determine if the near-surface soils possess corrosive
characteristics with respect to common construction materials. The corrosivity testing included a
determination of the electrical resistivity, pH, and chloride and nitrate concentrations of the soils,
as well as other tests. The results of some of these tests are presented below.
Sample Identification
Saturated
Resistivity
(ohm-cm)
pH Chlorides
(mg/kg)
Nitrates
(mg/kg)
B-1 @ 0 to 5 feet
(Previous Study) 12,000 7.3 0.7 13
B-8 @ 0 to 5 feet
(Previous Study) 14,800 7.8 Not Detected 5.5
B-20 @ 0 to 5 feet 38,800 8.0 2.4 7.0
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 11
6.0 CONCLUSIONS AND RECOMMENDATIONS
Based on the results of our review, field exploration, laboratory testing and geotechnical analysis,
the proposed development is considered feasible from a geotechnical standpoint. The
recommendations contained in this report should be taken into the design, construction, and
grading considerations.
The recommendations in this report are contingent upon all grading and foundation construction
activities being monitored by the geotechnical engineer of record. The recommendations are
provided with the assumption that an adequate program of client consultation, construction
monitoring, and testing will be performed during the final design and construction phases to verify
compliance with these recommendations. Maintaining Southern California Geotechnical, Inc.,
(SCG) as the geotechnical consultant from the beginning to the end of the project will provide
continuity of services. The geotechnical engineering firm providing testing and observation
services shall assume the responsibility of Geotechnical Engineer of Record.
The Grading Guide Specifications, included as Appendix D, should be considered part of this
report, and should be incorporated into the project specifications. The contractor and/or owner
of the development should bring to the attention of the geotechnical engineer any conditions that
differ from those stated in this report, or which may be detrimental for the development.
6.1 Seismic Design Considerations
The subject site is located in an area which is subject to strong ground motions due to
earthquakes. The performance of a site specific seismic hazards analysis was beyond the scope
of this investigation. However, numerous faults capable of producing significant ground motions
are located near the subject site. Due to economic considerations, it is not generally considered
reasonable to design a structure that is not susceptible to earthquake damage. Therefore,
significant damage to structures may be unavoidable during large earthquakes. The proposed
structures should, however, be designed to resist structural collapse and thereby provide
reasonable protection from serious injury, catastrophic property damage and loss of life.
Faulting and Seismicity
Research of available maps indicates that the subject site is not located within an Alquist-Priolo
Earthquake Fault Zone. Furthermore, SCG did not identify any evidence of faulting during the
geotechnical investigation. Therefore, the possibility of significant fault rupture on the site is
considered to be low.
Seismic Design Parameters
The California Building Code (CBC) provides procedures for earthquake resistant structural design
that include considerations for on-site soil conditions, occupancy, and the configuration of the
structure including the structural system and height. The seismic design parameters presented
below are based on the soil profile and the proximity of known faults with respect to the subject
site.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
Page 12
Based on standards in place at the time of this report, the proposed development is expected to
be designed in accordance with the requirements of the 2019 edition of the California Building
Code (CBC), which was adopted on January 1, 2020.
The 2019 CBC Seismic Design Parameters have been generated using the SEAOC/OSHPD Seismic
Design Maps Tool, a web-based software application available at the website
www.seismicmaps.org. This software application calculates seismic design parameters in
accordance with several building code reference documents, including ASCE 7-16, upon which
the 2019 CBC is based. The application utilizes a database of risk-targeted maximum considered
earthquake (MCER) site accelerations at 0.01-degree intervals for each of the code documents.
The tables below were created using data obtained from the application. The output generated
from this program is included as Plate E-1 in Appendix E of this report.
The 2019 CBC requires that a site-specific ground motion study be performed in accordance with
Section 11.4.8 of ASCE 7-16 for Site Class D sites with a mapped S1 value greater than 0.2.
However, Section 11.4.8 of ASCE 7-16 also indicates an exception to the requirement for a site-
specific ground motion hazard analysis for certain structures on Site Class D sites. The
commentary for Section 11 of ASCE 7-16 (Page 534 of Section C11 of ASCE 7-16) indicates that
“In general, this exception effectively limits the requirements for site-specific hazard analysis to
very tall and or flexible structures at Site Class D sites.” Based on our understanding of the
proposed development, the seismic design parameters presented below were
calculated assuming that the exception in Section 11.4.8 applies to the proposed
structure at this site. However, the structural engineer should verify that this
exception is applicable to the proposed structure. Based on the exception, the spectral
response accelerations presented below were calculated using the site coefficients (Fa and Fv)
from Tables 1613.2.3(1) and 1613.2.3(2) presented in Section 16.4.4 of the 2019 CBC.
2019 CBC SEISMIC DESIGN PARAMETERS
Parameter Value
Mapped MCER Acceleration at 0.2 sec Period SS 1.812
Mapped MCER Acceleration at 1.0 sec Period S1 0.616
Site Class --- D
Site Modified Spectral Acceleration at 0.2 sec Period SMS 1.812
Site Modified Spectral Acceleration at 1.0 sec Period SM1 1.047
Design Spectral Acceleration at 0.2 sec Period SDS 1.208
Design Spectral Acceleration at 1.0 sec Period SD1 0.698
It should be noted that the site coefficient Fv and the parameters SM1 and SD1 were not included
in the SEAOC/OSHPD Seismic Design Maps Tool output for the 2019 CBC. We calculated these
parameters-based on Table 1613.2.3(2) in Section 16.4.4 of the 2019 CBC using the value of S1
obtained from the Seismic Design Maps Tool, assuming that a site-specific ground motion hazards
analysis is not required for the proposed buildings at this site.
Proposed Commercial/Industrial Building – Fontana, CA
Project No. 19G241-3
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Liquefaction
Liquefaction is the loss of strength in generally cohesionless, saturated soils when the pore-water
pressure induced in the soil by a seismic event becomes equal to or exceeds the overburden
pressure. The primary factors which influence the potential for liquefaction include groundwater
table elevation, soil type and plasticity characteristics, relative density of the soil, initial confining
pressure, and intensity and duration of ground shaking. The depth within which the occurrence
of liquefaction may impact surface improvements is generally identified as the upper 50 feet
below the existing ground surface. Liquefaction potential is greater in saturated, loose, poorly
graded fine sands with a mean (d50) grain size in the range of 0.075 to 0.2 mm (Seed and Idriss,
1971). Non-sensitive clayey (cohesive) soils which possess a plasticity index of at least 18 (Bray
and Sancio, 2006) are generally not considered to be susceptible to liquefaction, nor are those
soils which are above the historic static groundwater table.
The California Geological Survey (CGS) has not yet conducted detailed seismic hazards mapping
in the area of the subject site. The general liquefaction susceptibility of the site was determined
by research of the San Bernardino County Official Land Use Plan, General Plan, Geologic Hazard
Overlay. Map FH29-C for the Fontana Quadrangle indicates that the subject site is not located
within an area of liquefaction susceptibility. Based on the mapping performed by the county of
San Bernardino and the subsurface conditions encountered at the boring locations, liquefaction
is not considered to be a design concern for this project.
6.2 Geotechnical Design Considerations
General
The overall site is underlain by artificial fill soils, extending to depths of 2½ to 6½± feet below
the existing site grades. No documentation regarding the placement or compaction of these fill
soils has been provided nor is expected to be available. The existing fill soils, in their present
condition, are not considered suitable to support the foundations loads of new structure.
Additionally, demolition of the existing structures, and pavements, required to facilitate the
proposed development, is expected to cause extensive disturbance to the near-surface soils. The
recommended remedial grading will also remove any soils disturbed during demolition and replace
these materials as compacted structural fill.
As previously discussed, several areas of pavement distress (or possibly subsidence) were
observed at isolated areas within the southern and southeastern regions of the site. These areas
identified possible fill soils extending to depths of 4½ to 7± feet below existing site grades.
Additional remedial grading may be necessary at the time of remedial grading if these materials
are determined to represent undocumented fill soils.
Settlement
The recommended remedial grading will remove the existing undocumented fill soils and a portion
of the near-surface native alluvial soils and replace these materials as compacted structural fill.
The native soils that will remain in place below the recommended depth of overexcavation possess
favorable consolidation/collapse characteristics and will not be subject to large stress increases
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Project No. 19G241-3
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from the foundations of the new structure. Therefore, following completion of the recommended
grading, post-construction settlements are expected to be within tolerable limits.
Expansion
The near-surface soils generally consist of sands and silty sands with no appreciable clay content.
These materials have been visually classified as non-expansive. Therefore, no design
considerations related to expansive soils are considered warranted for this site.
Soluble Sulfates
The results of the soluble sulfate testing indicate that the level of soluble sulfates within the
selected samples of the on-site soils correspond to Class S0 with respect to the American Concrete
Institute (ACI) Publication 318-05 Building Code Requirements for Structural Concrete and
Commentary, Section 4.3. Therefore, specialized concrete mix designs are not considered to be
necessary, with regard to sulfate protection purposes. It is, however, recommended that
additional soluble sulfate testing be conducted at the completion of rough grading to verify the
soluble sulfate concentrations of the soils which are present at pad grade within the building area.
Corrosion Potential
The results of laboratory testing indicate that the on-site soils possess saturated resistivity values
of 12,000 to 38,000 ohm-cm, and pH values of 7.3 to 8.0. These test results have been evaluated
in accordance with guidelines published by the Ductile Iron Pipe Research Association (DIPRA).
The DIPRA guidelines consist of a point system by which characteristics of the soils are used to
quantify the corrosivity characteristics of the site. Sulfides, and redox potential are factors that
are also used in the evaluation procedure. We have evaluated the corrosivity characteristics of
the on-site soils using resistivity, pH, and moisture content. Based on these factors, and utilizing
the DIPRA procedure, the on-site soils are not considered to be corrosive to ductile iron pipe.
However, SCG does not practice in the area of corrosion engineering. Therefore, the client may
also wish to contact a corrosion engineer to provide a more thorough evaluation.
Based on American Concrete Institute (ACI) Publication 318 Building Code Requirements for
Structural Concrete and Commentary, reinforced concrete that is exposed to external sources of
chlorides requires corrosion protection for the steel reinforcement contained within the concrete.
ACI 318 defines concrete exposed to moisture and an external source of chlorides as “severe” or
exposure category C2. ACI 318 does not clearly define a specific chloride concentration at which
contact with the adjacent soil will constitute a “C2” or severe exposure. However, the Caltrans
Memo to Designers 10-5, Protection of Reinforcement Against Corrosion Due to Chlorides, Acids
and Sulfates, dated June 2010, indicates that soils possessing chloride concentrations greater
than 500 mg/kg are considered to be corrosive to reinforced concrete. The results of the
additional laboratory testing indicate chloride concentrations of up to 2.4 ppm. Although the soils
contain some chlorides, we do not expect that the chloride concentrations of the tested soils are
high enough to constitute a “severe” or C2 chloride exposure. Therefore, expect a chloride
exposure category of C1 is appropriate for this site. Since SCG does not practice in the area of
corrosion engineering, the client may also wish to contact a corrosion engineer to provide a more
thorough evaluation.
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Shrinkage/Subsidence
Removal and recompaction of the near-surface alluvium and fill soils is estimated to result in an
average shrinkage of 3 to 11 percent. However, the estimated shrinkage of the individual soil
layers at the site is highly variable, with individual strata ranging from 0 to 16 percent shrinkage.
It should be noted that this shrinkage estimate is based on the results of dry density testing
performed on small-diameter samples of the existing soils taken at the boring locations. If a more
accurate and precise shrinkage estimate is desired, SCG can perform a shrinkage study involving
several excavated test-pits where in-place densities are determined using in-situ testing methods
instead of laboratory density testing on small-diameter samples. Please contact SCG for details
and a cost estimate regarding a shrinkage study, if desired.
Minor ground subsidence is expected to occur in the soils below the zone of removal, due to
settlement and machinery working. The subsidence is estimated to be 0.1± feet. This estimate
may be used for grading in areas that are underlain by native alluvial soils.
These estimates are based on previous experience and the subsurface conditions encountered at
the boring locations. The actual amount of subsidence is expected to be variable and will be
dependent on the type of machinery used, repetitions of use, and dynamic effects, all of which
are difficult to assess precisely.
Grading and Foundation Plan Review
No grading or foundation plans were available at the time of this report. It is therefore
recommended that we be provided with copies of the preliminary plans, when they become
available, for review with regard to the conclusions, recommendations, and assumptions
contained within this report.
6.3 Site Grading Recommendations
The grading recommendations presented below are based on the subsurface conditions
encountered at the boring locations and our understanding of the proposed development. We
recommend that all grading activities be completed in accordance with the Grading Guide
Specifications included as Appendix D of this report, unless superseded by site-specific
recommendations presented below.
Site Stripping and Demolition
Demolition of the existing buildings, pavements, and any associated improvements will be
necessary to facilitate the proposed development site. Demolition of the existing structures should
include all foundations, floor slabs, and any associated utilities. Any septic systems encountered
during demolition and/or grading (if present) should be removed in their entirety. Any associated
leach fields or other existing underground improvements should also be removed in their entirety.
All applicable federal, state and local specifications and regulations should be followed in
demolition, abandonment, and disposal of the existing structures and resulting debris.
Initial site stripping should include removal of the surficial vegetation from the site. Limited
stripping is expected to be necessary within the planter areas. Removal of trees should include
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the root systems, with the resultant excavation backfilled with compacted structural fill soils. The
actual extent of site stripping should be determined in the field by the geotechnical engineer,
based on the organic content and stability of the materials encountered.
Treatment of Existing Soils: Building Pad
Remedial grading will be necessary within the proposed building pad area to remove the existing
undocumented fill soils and the upper portion of the near-surface native alluvial soils. The fill soils
extend to depths of 2½ to 6½± feet at the boring locations. As discussed above, these materials
are considered to represent undocumented fill. The existing fill soils should be removed in their
entirety. In addition, the overexcavation is recommended to extend to a depth of at least 5 feet
below existing grade and 3 feet below proposed building pad subgrade elevation, whichever is
greater. Within the influence zones of the new foundations, the overexcavation should extend to
a depth of at least 3 feet below proposed foundation bearing grade.
The overexcavation areas should extend at least 5 feet beyond foundation edge and building
perimeters, and to an extent equal to the depth of fill below the new foundations. If the proposed
structure will incorporate any exterior columns (such as for a canopy or overhang) the area of
overexcavation should also encompass these areas.
Following completion of the overexcavation, the subgrade soils within the building area should
be evaluated by the geotechnical engineer to verify their suitability to serve as the structural fill
subgrade, as well as to support the foundation loads of the new structure. This evaluation should
include proofrolling and probing to identify any soft, loose or otherwise unstable soils that must
be removed. Some localized areas of deeper excavation may be required if additional fill soils, or
if loose, porous, or low-density native soils are encountered at the base of the overexcavation.
The possible fill soils should be further evaluated at the time of grading. If these are
determined to be undocumented fill soils, they should be removed in their entirety.
After a suitable overexcavation subgrade has been achieved, the exposed soils should be scarified
to a depth of at least 12 inches and moisture conditioned to achieve a moisture content of 0 to 4
percent above optimum moisture content. The subgrade soils should then be recompacted to at
least 90 percent of the ASTM D-1557 maximum dry density. The building pad area may then be
raised to grade with previously excavated soils or imported structural fill.
Treatment of Existing Soils: Retaining Walls and Site Walls
The existing soils within the areas of any proposed retaining walls and non-retaining site walls
should be overexcavated to a depth of 3 feet below foundation bearing grade and replaced as
compacted structural fill, as discussed above for the proposed building pad. Any undocumented
fill soils within any of these foundation areas should be removed in their entirety. The
overexcavation areas should extend at least 5 feet beyond the foundation perimeters, and to an
extent equal to the depth of fill below the new foundations. Please note that any erection pads
used to construct the walls are considered to be part of the foundation system. The
overexcavation subgrade soils should be evaluated by the geotechnical engineer prior to
scarifying, moisture conditioning, and recompacting the upper 12 inches of exposed subgrade
soils. The previously excavated soils may then be replaced as compacted structural fill.
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Treatment of Existing Soils: Parking and Drive Areas
Based on economic considerations, overexcavation of the existing undocumented fill soils in the
new parking and drive areas is not considered warranted, with the exception of areas where lower
strength or unstable soils are identified by the geotechnical engineer during grading. The
previously identified former abandoned storage tank areas should be evaluated
during grading to determine whether any encountered loose soils should be
overexcavated.
Subgrade preparation in the new parking and drive areas should initially consist of removal of all
soils disturbed during stripping and demolition operations. Depending on the conditions
encountered during grading, isolated areas within the abandoned storage tanks may
require removals extending to depths of 7 to 9 feet. The geotechnical engineer should
then evaluate the subgrade to identify any areas of additional unsuitable soils. The subgrade soils
should then be scarified to a depth of 12 inches, moisture conditioned to 0 to 4 percent above
optimum, and recompacted to at least 90 percent of the ASTM D-1557 maximum dry density.
Based on the presence of undocumented fill soils throughout the site, it is expected that some
isolated areas of additional overexcavation may be required to remove zones of lower strength,
unsuitable soils.
The grading recommendations presented above for the proposed parking and drive areas assume
that the owner and/or developer can tolerate minor amounts of settlement within the proposed
parking areas. The grading recommendations presented above do not completely mitigate the
extent of existing undocumented fill soils in the parking areas. As such, settlement and associated
pavement distress could occur. Typically, repair of such distressed areas involves significantly
lower costs than completely mitigating these soils at the time of construction. If the owner cannot
tolerate the risk of such settlements, the parking and drive areas should be overexcavated to a
depth of 2 feet below proposed pavement subgrade elevation, with the resulting soils replaced
as compacted structural fill.
Fill Placement
• Fill soils should be placed in thin (6 inches), near-horizontal lifts, moisture conditioned
to within 0 to 4 percent above the optimum moisture content, and compacted.
• On-site soils may be used for fill provided they are cleaned of any debris to the satisfaction
of the geotechnical engineer.
• All grading and fill placement activities should be completed in accordance with the
requirements of the 2019 CBC and the grading code of the city of Fontana.
• All fill soils should be compacted to at least 90 percent of the ASTM D-1557 maximum dry
density.
• Compaction tests should be performed periodically by the geotechnical engineer as
random verification of compaction and moisture content. These tests are intended to aid
the contractor. Since the tests are taken at discrete locations and depths, they may not
be indicative of the entire fill and therefore should not relieve the contractor of his
responsibility to meet the job specifications.
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Imported Structural Fill
All imported structural fill should consist of very low expansive (EI < 20), well graded soils
possessing at least 10 percent fines (that portion of the sample passing the No. 200 sieve).
Additional specifications for structural fill are presented in the Grading Guide Specifications,
included as Appendix D.
Utility Trench Backfill
In general, all utility trench backfill should be compacted to at least 90 percent of the ASTM D-
1557 maximum dry density. As an alternative, a clean sand (minimum Sand Equivalent of 30)
may be placed within trenches and compacted in place (jetting or flooding is not recommended).
It is recommended that materials in excess of 3 inches in size not be used for utility trench backfill.
Compacted trench backfill should conform to the requirements of the local grading code, and
more restrictive requirements may be indicated by the city of Fontana. All utility trench backfills
should be witnessed by the geotechnical engineer. The trench backfill soils should be compaction
tested where possible; probed and visually evaluated elsewhere.
Utility trenches which parallel a footing, and extending below a 1h:1v plane projected from the
outside edge of the footing should be backfilled with structural fill soils, compacted to at least 90
percent of the ASTM D-1557 standard. Pea gravel backfill should not be used for these trenches.
Any soils used to backfill voids around subsurface utility structures, such as manholes or vaults,
should be placed as compacted structural fill. If it is not practical to place compacted fill in these
areas, then such void spaces may be backfilled with lean concrete slurry. Uncompacted pea gravel
or sand is not recommended for backfilling these voids since these materials have a potential to
settle and thereby cause distress of pavements placed around these subterranean structures.
6.4 Construction Considerations
Excavation Considerations
The near surface soils are predominately granular in nature. These materials will likely be subject
to caving within shallow excavations. Where caving occurs within shallow excavations, flattened
excavation slopes may be sufficient to provide excavation stability. On a preliminary basis, the
inclination of temporary slopes should not exceed 2h:1v. Deeper excavations may require some
form of external stabilization such as shoring or bracing. Maintaining adequate moisture content
within the near-surface soils will improve excavation stability. All excavation activities on this site
should be conducted in accordance with Cal-OSHA regulations.
Groundwater
The static groundwater table at this site is considered to exist at a depth greater than 25 feet.
Therefore, groundwater is not expected to impact the grading or foundation construction
activities.
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6.5 Foundation Design and Construction
Based on the preceding grading recommendations, it is assumed that the new building pad will
be underlain by structural fill soils used to replace existing undocumented fill soils and the upper
portion of the near-surface native alluvium. These new structural fill soils are expected to extend
to depths of at least 3 feet below proposed foundation bearing grade. Based on this subsurface
profile, the proposed structure may be supported on conventional shallow foundations.
Foundation Design Parameters
New square and rectangular footings may be designed as follows:
• Maximum, net allowable soil bearing pressure: 2,500 lbs/ft2.
• Minimum wall/column footing width: 14 inches/24 inches.
• Minimum longitudinal steel reinforcement within strip footings: Two (2) No. 5 rebars (1
top and 1 bottom).
• Minimum foundation embedment: 12 inches into suitable structural fill soils, and at least
18 inches below adjacent exterior grade. Interior column footings may be placed
immediately beneath the floor slab.
• It is recommended that the perimeter building foundations be continuous across all
exterior doorways. Any flatwork adjacent to the exterior doors should be doweled into the
perimeter foundations in a manner determined by the structural engineer.
The allowable bearing pressure presented above may be increased by one-third when considering
short duration wind or seismic loads. The minimum steel reinforcement recommended above is
based on geotechnical considerations; additional reinforcement may be necessary for structural
considerations. The actual design of the foundations should be determined by the structural
engineer.
Foundation Construction
The foundation subgrade soils should be evaluated at the time of overexcavation, as discussed
in Section 6.3 of this report. It is further recommended that the foundation subgrade soils be
evaluated by the geotechnical engineer immediately prior to steel or concrete placement. Soils
suitable for direct foundation support should consist of newly placed structural fill, compacted to
at least 90 percent of the ASTM D-1557 maximum dry density. Any unsuitable materials should
be removed to a depth of suitable bearing compacted structural fill, with the resulting excavations
backfilled with compacted fill soils. As an alternative, lean concrete slurry (500 to 1,500 psi) may
be used to backfill such isolated overexcavations.
The foundation subgrade soils should also be properly moisture conditioned to 0 to 4 percent
above the Modified Proctor optimum, to a depth of at least 12 inches below bearing grade. Since
it is typically not feasible to increase the moisture content of the floor slab and foundation
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subgrade soils once rough grading has been completed, care should be taken to maintain the
moisture content of the building pad subgrade soils throughout the construction process.
Estimated Foundation Settlements
Post-construction total and differential settlements of shallow foundations designed and
constructed in accordance with the previously presented recommendations are estimated to be
less than 1.0 and 0.5 inches, respectively. Differential movements are expected to occur over a
60-foot span, thereby resulting in an angular distortion of less than 0.002 inches per inch.
Lateral Load Resistance
Lateral load resistance will be developed by a combination of friction acting at the base of
foundations and slabs and the passive earth pressure developed by footings below grade. The
following friction and passive pressure may be used to resist lateral forces:
• Passive Earth Pressure: 300 lbs/ft3
• Friction Coefficient: 0.30
These are allowable values, and include a factor of safety. When combining friction and passive
resistance, the passive pressure component should be reduced by one-third. These values assume
that footings will be poured directly against compacted structural fill. The maximum allowable
passive pressure is 2,500 lbs/ft2.
6.6 Floor Slab Design and Construction
Subgrades which will support the new floor slab should be prepared in accordance with the
recommendations contained in the Site Grading Recommendations section of this report.
Based on the anticipated grading which will occur at this site, the floor of the new structure may
be constructed as a conventional slab-on-grade supported on newly placed structural fill soils.
These fill soils are expected to extend to a depth of at least 3 feet below finished pad grade.
Based on geotechnical considerations, the floor slab may be designed as follows:
• Minimum slab thickness: 6 inches.
• Modulus of Subgrade Reaction: k = 150 psi/in
• Minimum slab reinforcement: Reinforcement is not required for geotechnical conditions.
The actual floor slab reinforcement should be determined by the structural engineer,
based upon the imposed loading.
• Slab underlayment: If moisture sensitive floor coverings will be used the minimum slab
underlayment should consist of a moisture vapor barrier constructed below the entire area
where such moisture sensitive floor coverings are anticipated. The moisture vapor barrier
should meet or exceed the Class A rating as defined by ASTM E 1745-97 and have a
permeance rating less than 0.01 perms as described in ASTM E 96-95 and ASTM E 154-
88. A polyolefin material such as 15-mil Stego® Wrap Vapor Barrier or equivalent will meet
these specifications. The moisture vapor barrier should be properly constructed in
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accordance with all applicable manufacturer specifications. The need for sand and/or the
amount of sand above the moisture vapor barrier should be specified by the structural
engineer or concrete contractor. The selection of sand above the barrier is not a
geotechnical engineering issue and hence outside our purview.
• Moisture condition the floor slab subgrade soils to 0 to 4 percent above the Modified
Proctor optimum moisture content, to a depth of 12 inches. The moisture content of the
floor slab subgrade soils should be verified by the geotechnical engineer within 24 hours
prior to concrete placement.
• Proper concrete curing techniques should be utilized to reduce the potential for slab
curling or the formation of excessive shrinkage cracks.
The actual design of the floor slab should be completed by the structural engineer to verify
adequate thickness and reinforcement.
6.7 Retaining Wall Design and Construction
Small retaining walls are expected to be necessary in the area of the new truck loading docks and
may also be required to facilitate the new site grades. The parameters recommended for use in
the design of these walls are presented below.
Retaining Wall Design Parameters
Based on the soil conditions encountered at the boring locations, the following parameters may
be used in the design of new retaining walls for this site. We have provided parameters assuming
the use of on-site soils for retaining wall backfill. The on-site soils generally consist of silty sands
and sands. Based on their classification, these materials are expected to possess a friction angle
of at least 30 degrees when compacted to 90 percent of the ASTM-1557 maximum dry density.
If desired, SCG could provide design parameters for an alternative select backfill material behind
the retaining walls. The use of select backfill material could result in lower lateral earth pressures.
In order to use the design parameters for the imported select fill, this material must be placed
within the entire active failure wedge. This wedge is defined as extending from the heel of the
retaining wall upwards at an angle of approximately 60° from horizontal. If select backfill material
behind the retaining wall is desired, SCG should be contacted for supplementary
recommendations.
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RETAINING WALL DESIGN PARAMETERS
Design Parameter
Soil Type
On-Site Silty Sands and Sands
Internal Friction Angle () 30
Unit Weight 130 lbs/ft3
Equivalent
Fluid Pressure:
Active Condition
(level backfill) 43 lbs/ft3
Active Condition
(2h:1v backfill) 70 lbs/ft3
At-Rest Condition
(level backfill) 65 lbs/ft3
The walls should be designed using a soil-footing coefficient of friction of 0.30 and an equivalent
passive pressure of 300 lbs/ft3. The structural engineer should incorporate appropriate factors of
safety in the design of the retaining walls.
The active earth pressure may be used for the design of retaining walls that do not directly
support structures or support soils that in turn support structures and which will be allowed to
deflect. The at-rest earth pressure should be used for walls that will not be allowed to deflect
such as those which will support foundation bearing soils, or which will support foundation loads
directly.
Where the soils on the toe side of the retaining wall are not covered by a "hard" surface such as
a structure or pavement, the upper 1 foot of soil should be neglected when calculating passive
resistance due to the potential for the material to become disturbed or degraded during the life
of the structure.
Retaining Wall Foundation Design
The retaining wall foundations should be supported within newly placed structural fill, extending
to a depth of at least 3 feet below the proposed bearing grade. Foundations to support new
retaining walls should be designed in accordance with the general Foundation Design Parameters
presented in a previous section of this report.
Seismic Lateral Earth Pressures
In accordance with the 2019 CBC, any retaining walls more than 6 feet in height must be designed
for seismic lateral earth pressures. If walls 6 feet or more are required for this site, the
geotechnical engineer should be contacted for supplementary seismic lateral earth pressure
recommendations.
Backfill Material
On-site soils may be used to backfill the retaining walls. However, all backfill material placed
within 3 feet of the back wall face should have a particle size no greater than 3 inches. The
retaining wall backfill materials should be well graded.
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It is recommended that a properly installed prefabricated drainage composite such as the
MiraDRAIN 6000XL (or approved equivalent), which is specifically designed for use behind
retaining walls be used. If the drainage composite material is not covered by an impermeable
surface, such as a structure or pavement, a 12-inch thick layer of a low permeability soil should
be placed over the backfill to reduce surface water migration to the underlying soils. The drainage
composite should be separated from the backfill soils by a suitable geotextile, approved by the
geotechnical engineer.
All retaining wall backfill should be placed and compacted under engineering- controlled
conditions in the necessary layer thicknesses to ensure an in-place density between 90 and 93
percent of the maximum dry density as determined by the Modified Proctor test (ASTM D1557-
91). Care should be taken to avoid over-compaction of the soils behind the retaining walls, and
the use of heavy compaction equipment should be avoided.
Subsurface Drainage
As previously indicated, the retaining wall design parameters are based upon drained backfill
conditions. Consequently, some form of permanent drainage system will be necessary in
conjunction with the appropriate backfill material. Subsurface drainage may consist of either:
• A weep hole drainage system typically consisting of a series of 4-inch diameter holes in
the wall situated slightly above the ground surface elevation on the exposed side of the
wall and at an approximate 8-foot on-center spacing. The weep holes should include a 2
cubic foot pocket of open graded gravel, surrounded by an approved geotextile fabric, at
each weep hole location.
• A 4-inch diameter perforated pipe surrounded by 2 cubic feet of gravel per linear foot of
drain placed behind the wall, above the retaining wall footing. The gravel layer should be
wrapped in a suitable geotextile fabric to reduce the potential for migration of fines. The
footing drain should be extended to daylight or tied into a storm drainage system.
6.8 Pavement Design Parameters
Site preparation in the pavement area should be completed as previously recommended in the
Site Grading Recommendations section of this report. The subsequent pavement
recommendations assume proper drainage and construction monitoring, and are based on either
PCA or CALTRANS design parameters for a twenty (20) year design period. However, these
designs also assume a routine pavement maintenance program to obtain the anticipated 20-year
pavement service life.
Pavement Subgrades
It is anticipated that the new pavements will be primarily supported on a layer of compacted
structural fill, consisting of scarified, thoroughly moisture conditioned and recompacted existing
soils. The on-site soils generally consist of silty sands and sands. Based on their classification,
these materials are expected to possess excellent pavement support characteristics, with
estimated R-values greater than 50. Since R-value testing was not included in the scope of
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services for this project, the subsequent pavement design is based upon an assumed R-value of
50. Any fill material imported to the site should have support characteristics equal to or greater
than that of the on-site soils and be placed and compacted under engineering controlled
conditions. It is recommended that R-value testing be performed after completion of rough
grading.
Asphaltic Concrete
Presented below are the recommended thicknesses for new flexible pavement structures
consisting of asphaltic concrete over a granular base. The pavement designs are based on the
traffic indices (TI’s) indicated. The client and/or civil engineer should verify that these TI’s are
representative of the anticipated traffic volumes. If the client and/or civil engineer determine that
the expected traffic volume will exceed the applicable traffic index, we should be contacted for
supplementary recommendations. The design traffic indices equate to the following approximate
daily traffic volumes over a 20 year design life, assuming six operational traffic days per week.
Traffic Index No. of Heavy Trucks per Day
4.0 0
5.0 1
6.0 3
7.0 11
8.0 35
For the purpose of the traffic volumes indicated above, a truck is defined as a 5-axle tractor trailer
unit with one 8-kip axle and two 32-kip tandem axles. All of the traffic indices allow for 1,000
automobiles per day.
ASPHALT PAVEMENTS (R = 50)
Materials
Thickness (inches)
Parking
Stalls
(TI = 4.0)
Auto Drive
Lanes
(TI = 5.0)
Truck Traffic
(TI = 6.0) (TI = 7.0) (TI = 8.0)
Asphalt Concrete 3 3 3½ 4 5
Aggregate Base 3 3 4 5 5
Compacted Subgrade 12 12 12 12 12
The aggregate base course should be compacted to at least 95 percent of the ASTM D-1557
maximum dry density. The asphaltic concrete should be compacted to at least 95 percent of the
Marshall maximum density, as determined by ASTM D-2726. The aggregate base course may
consist of crushed aggregate base (CAB) or crushed miscellaneous base (CMB), which is a
recycled gravel, asphalt and concrete material. The gradation, R-Value, Sand Equivalent, and
Percentage Wear of the CAB or CMB should comply with appropriate specifications contained in
the current edition of the “Greenbook” Standard Specifications for Public Works Construction.
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Portland Cement Concrete
The preparation of the subgrade soils within concrete pavement areas should be performed as
previously described for proposed asphalt pavement areas. The minimum recommended
thicknesses for the Portland Cement Concrete pavement sections are as follows:
PORTLAND CEMENT CONCRETE PAVEMENTS (R = 50)
Materials
Thickness (inches)
Automobile
Parking and
Drive Areas
(TI=4.0 & 5.0)
Truck Traffic
(TI =6.0) (TI =7.0) (TI =8.0)
PCC 5 5 5½ 6½
Compacted Subgrade
(95% minimum compaction) 12 12 12 12
The concrete should have a 28-day compressive strength of at least 3,000 psi. The maximum
joint spacing within all of the PCC pavements is recommended to be equal to or less than 30
times the pavement thickness.
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7.0 GENERAL COMMENTS
This report has been prepared as an instrument of service for use by the client, in order to aid in
the evaluation of this property and to assist the architects and engineers in the design and
preparation of the project plans and specifications. This report may be provided to the
contractor(s) and other design consultants to disclose information relative to the project.
However, this report is not intended to be utilized as a specification in and of itself, without
appropriate interpretation by the project architect, civil engineer, and/or structural engineer. The
reproduction and distribution of this report must be authorized by the client and Southern
California Geotechnical, Inc. Furthermore, any reliance on this report by an unauthorized third
party is at such party’s sole risk, and we accept no responsibility for damage or loss which may
occur. The client(s)’ reliance upon this report is subject to the Engineering Services Agreement,
incorporated into our proposal for this project.
The analysis of this site was based on a subsurface profile interpolated from limited discrete soil
samples. While the materials encountered in the project area are considered to be representative
of the total area, some variations should be expected between boring locations and sample
depths. If the conditions encountered during construction vary significantly from those detailed
herein, we should be contacted immediately to determine if the conditions alter the
recommendations contained herein.
This report has been based on assumed or provided characteristics of the proposed development.
It is recommended that the owner, client, architect, structural engineer, and civil engineer
carefully review these assumptions to ensure that they are consistent with the characteristics of
the proposed development. If discrepancies exist, they should be brought to our attention to
verify that they do not affect the conclusions and recommendations contained herein. We also
recommend that the project plans and specifications be submitted to our office for review to
verify that our recommendations have been correctly interpreted.
The analysis, conclusions, and recommendations contained within this report have been
promulgated in accordance with generally accepted professional geotechnical engineering
practice. No other warranty is implied or expressed.
SITE
PROPOSED COMMERCIAL/INDUSTRIAL BUILDING
SCALE: 1" = 2000'
DRAWN: RB
CHKD: RGT
SCG PROJECT
19G241-3
PLATE 1
SITE LOCATION MAP
FONTANA, CALIFORNIA
SOURCE: USGS TOPOGRAPHIC MAP OF THE FONTANA 7.5
MINUTE QUADRANGLE, SAN BERNARDINO COUNTY,
CALIFORNIA, 2018.
B-6
B-1
B-2
B-3
B-4
B-5
B-8
B-9 B-7
B-17
B-16
B-15
B-14
B-13
B-12
B-11
B-10
AREA 1
AREA 2
AREA 3
B-18
B-19
B-20
BUILDING AREA
442,790 S.F.
N.A.P.N.A.P.N.A.P.
SLOVER AVENUE
CA
T
A
W
B
A
A
V
E
N
U
E
CI
T
R
U
S
A
V
E
N
U
E
N.A.P.
POSSIBLE
ABANDONED
UNDERGROUND
TANKS
SCALE: 1" = 100'
DRAWN: RB
CHKD: RGT
PLATE 2
SCG PROJECT
19G241-3
PROPOSED COMMERCIAL/INDUSTRIAL BUILDING
BORING LOCATION PLAN
NO
R
T
H
So
C
a
l
G
e
o
FONTANA, CALIFORNIA
NOTE: CONCEPTUAL SITE PLAN PREPARED BY HPA.
GEOTECHNICAL LEGEND
APPROXIMATE BORING LOCATION
AERIAL PHOTOGRAPH OBTAINED FROM GOOGLE EARTH.
PREVIOUS BORING LOCATION
(DISTRESSED PAVEMENT AREAS)
PREVIOUS BORING LOCATION
(SCG PROJECT NO. 19G241-1)
BORING LOG LEGEND
SAMPLE TYPE GRAPHICAL
SYMBOL SAMPLE DESCRIPTION
AUGER SAMPLE COLLECTED FROM AUGER CUTTINGS, NO FIELD
MEASUREMENT OF SOIL STRENGTH. (DISTURBED)
CORE ROCK CORE SAMPLE: TYPICALLY TAKEN WITH A DIAMOND-TIPPED CORE BARREL. TYPICALLY USED ONLY IN HIGHLY CONSOLIDATED BEDROCK.
GRAB 1
SOIL SAMPLE TAKEN WITH NO SPECIALIZED
EQUIPMENT, SUCH AS FROM A STOCKPILE OR THE GROUND SURFACE. (DISTURBED)
CS CALIFORNIA SAMPLER: 2-1/2 INCH I.D. SPLIT BARREL SAMPLER, LINED WITH 1-INCH HIGH BRASS RINGS.
DRIVEN WITH SPT HAMMER. (RELATIVELY UNDISTURBED)
NSR
NO RECOVERY: THE SAMPLING ATTEMPT DID NOT RESULT IN RECOVERY OF ANY SIGNIFICANT SOIL OR
ROCK MATERIAL.
SPT STANDARD PENETRATION TEST: SAMPLER IS A 1.4 INCH INSIDE DIAMETER SPLIT BARREL, DRIVEN 18 INCHES WITH THE SPT HAMMER. (DISTURBED)
SH SHELBY TUBE: TAKEN WITH A THIN WALL SAMPLE
TUBE, PUSHED INTO THE SOIL AND THEN EXTRACTED. (UNDISTURBED)
VANE VANE SHEAR TEST: SOIL STRENGTH OBTAINED USING A 4 BLADED SHEAR DEVICE. TYPICALLY USED IN SOFT CLAYS-NO SAMPLE RECOVERED.
COLUMN DESCRIPTIONS
DEPTH: Distance in feet below the ground surface.
SAMPLE: Sample Type as depicted above.
BLOW COUNT: Number of blows required to advance the sampler 12 inches using a 140 lb
hammer with a 30-inch drop. 50/3” indicates penetration refusal (>50 blows)
at 3 inches. WH indicates that the weight of the hammer was sufficient to
push the sampler 6 inches or more.
POCKET PEN.: Approximate shear strength of a cohesive soil sample as measured by pocket
penetrometer.
GRAPHIC LOG: Graphic Soil Symbol as depicted on the following page.
DRY DENSITY: Dry density of an undisturbed or relatively undisturbed sample in lbs/ft3.
MOISTURE CONTENT: Moisture content of a soil sample, expressed as a percentage of the dry weight.
LIQUID LIMIT: The moisture content above which a soil behaves as a liquid.
PLASTIC LIMIT: The moisture content above which a soil behaves as a plastic.
PASSING #200 SIEVE: The percentage of the sample finer than the #200 standard sieve.
UNCONFINED SHEAR: The shear strength of a cohesive soil sample, as measured in the unconfined state.
SM
SP
COARSE
GRAINEDSOILS
SW
TYPICAL
DESCRIPTIONS
WELL-GRADED GRAVELS, GRAVEL -
SAND MIXTURES, LITTLE OR NOFINES
SILTY GRAVELS, GRAVEL - SAND -
SILT MIXTURES
LETTERGRAPH
POORLY-GRADED GRAVELS,
GRAVEL - SAND MIXTURES, LITTLEOR NO FINES
GC
GM
GP
GW
POORLY-GRADED SANDS,
GRAVELLY SAND, LITTLE OR NOFINES
SILTSAND
CLAYS
MORE THAN 50%
OF MATERIAL ISLARGER THANNO. 200 SIEVE
SIZE
MORE THAN 50%OF MATERIAL IS
SMALLER THANNO. 200 SIEVESIZE
MORE THAN 50%OF COARSEFRACTION
PASSING ON NO.4 SIEVE
MORE THAN 50%OF COARSE
FRACTIONRETAINED ON NO.4 SIEVE CLAYEY GRAVELS, GRAVEL - SAND -
CLAY MIXTURES
FINEGRAINED
SOILS
SYMBOLSMAJOR DIVISIONS
SOIL CLASSIFICATION CHART
PT
OH
CH
MH
OL
CL
ML
CLEAN SANDS
SC
SILTY SANDS, SAND - SILTMIXTURES
CLAYEY SANDS, SAND - CLAY
MIXTURES
INORGANIC SILTS AND VERY FINESANDS, ROCK FLOUR, SILTY OR
CLAYEY FINE SANDS OR CLAYEYSILTS WITH SLIGHT PLASTICITY
INORGANIC CLAYS OF LOW TO
MEDIUM PLASTICITY, GRAVELLYCLAYS, SANDY CLAYS, SILTY CLAYS,LEAN CLAYS
ORGANIC SILTS AND ORGANICSILTY CLAYS OF LOW PLASTICITY
INORGANIC SILTS, MICACEOUS OR
DIATOMACEOUS FINE SAND ORSILTY SOILS
INORGANIC CLAYS OF HIGH
PLASTICITY
ORGANIC CLAYS OF MEDIUM TO
HIGH PLASTICITY, ORGANIC SILTS
PEAT, HUMUS, SWAMP SOILS WITHHIGH ORGANIC CONTENTS
SILTS
AND
CLAYS
GRAVELS WITH
FINES
SAND
AND
SANDY
SOILS (LITTLE OR NO FINES)
SANDS WITH
FINES
LIQUID LIMITLESS THAN 50
LIQUID LIMIT
GREATER THAN 50
HIGHLY ORGANIC SOILS
NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS
GRAVEL
AND
GRAVELLYSOILS
(APPRECIABLE
AMOUNT OF FINES)
(APPRECIABLE
AMOUNT OF FINES)
(LITTLE OR NO FINES)
WELL-GRADED SANDS, GRAVELLYSANDS, LITTLE OR NO FINES
CLEAN
GRAVELS
3
2
2
1
1
5
ASPHALTIC CONCRETE: 1± inch Asphaltic Concrete, nodiscernible Aggregate Base
ALLUVIUM: Light Brown Silty fine Sand, trace medium to coarseSand, trace fine to coarse Gravel, medium dense-dry to damp
Gray Brown fine to coarse Sand, trace to little Silt, little fine to
coarse Gravel, medium dense-dry to damp
Brown fine to coarse Sand, trace to little Silt, trace to little fine
Gravel, medium dense to very dense-dry to damp
Brown fine Sandy Silt, trace fine to coarse Gravel, trace medium
to coarse Sand, trace fine to coarse Gravel, medium dense-damp
Boring Terminated at 20'
13
20
26
27
62/11"
17
FIELD RESULTS
WATER DEPTH: Dry
CAVE DEPTH: 5 feet
READING TAKEN: At Completion
GR
A
P
H
I
C
L
O
G
BORING NO.
B-18
PO
C
K
E
T
P
E
N
.
(T
S
F
)
DRILLING DATE: 1/17/22
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ryan Bremer
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
JOB NO.: 19G241-3
PROJECT: Proposed C/I Building
LOCATION: Fontana, California
PLATE B-1
5
10
15
20
LABORATORY RESULTS
CO
M
M
E
N
T
S
TEST BORING LOG
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
BL
O
W
C
O
U
N
T
DESCRIPTION
SURFACE ELEVATION: --- MSL LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
TB
L
1
9
G
2
4
2
-
3
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
2
/
1
0
/
2
2
103
120
111
119
110
7
3
3
3
3
3
10
FILL: Light Brown Silty fine Sand, trace to little medium to coarseSand, trace fine Gravel, medium dense-damp to moist
ALLUVIUM: Light Gray fine to coarse Sand, little fine to coarseGravel, loose to medium dense-damp
Gray fine to coarse Sand, trace Silt, trace to little fine to coarse
Gravel, dense to very dense-damp
@ 13½ feet, some medium Silt, occasional Cobbles
Light Brown fine Sandy Silt, medium dense-moist
Boring Terminated at 20'
18
25
13
58
48
76/11"
11
FIELD RESULTS
WATER DEPTH: Dry
CAVE DEPTH: 12 feet
READING TAKEN: At Completion
GR
A
P
H
I
C
L
O
G
BORING NO.
B-19
PO
C
K
E
T
P
E
N
.
(T
S
F
)
DRILLING DATE: 1/17/22
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ryan Bremer
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
JOB NO.: 19G241-3
PROJECT: Proposed C/I Building
LOCATION: Fontana, California
PLATE B-2
5
10
15
20
LABORATORY RESULTS
CO
M
M
E
N
T
S
TEST BORING LOG
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
BL
O
W
C
O
U
N
T
DESCRIPTION
SURFACE ELEVATION: --- MSL LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
TB
L
1
9
G
2
4
2
-
3
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
2
/
1
0
/
2
2
110
121
116
123
117
7
9
3
3
3
3
3
FILL Dark Brown Silty fine Sand, little medium to coarse Sand,trace fine Gravel, loose to medium dense-damp to moist
ALLUVIUM: Light Gray Brown fine to coarse Sand, trace Silt,occasional Cobbles, medium dense to very dense-damp to moist
Boring Terminated at 20'
12
20
23
49
60
50/4"
15
FIELD RESULTS
WATER DEPTH: Dry
CAVE DEPTH: 13 feet
READING TAKEN: At Completion
GR
A
P
H
I
C
L
O
G
BORING NO.
B-20
PO
C
K
E
T
P
E
N
.
(T
S
F
)
DRILLING DATE: 1/17/22
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ryan Bremer
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
JOB NO.: 19G241-3
PROJECT: Proposed C/I Building
LOCATION: Fontana, California
PLATE B-3
5
10
15
20
LABORATORY RESULTS
CO
M
M
E
N
T
S
TEST BORING LOG
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
BL
O
W
C
O
U
N
T
DESCRIPTION
SURFACE ELEVATION: MSL LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
TB
L
1
9
G
2
4
2
-
3
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
2
/
1
0
/
2
2
Classification: Light Gray Brown fine to coarse Sand, trace Silt
Boring Number:B-20 Initial Moisture Content (%)9
Sample Number:---Final Moisture Content (%)17
Depth (ft)3 to 4 Initial Dry Density (pcf)121.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)128.2
Specimen Thickness (in)1.0 Percent Collapse (%)0.71
Proposed Commercial/Industrial Building
Fontana, CA
Project No. 19G241-3
PLATE C- 1
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Light Gray Brown fine to coarse Sand, trace Silt
Boring Number:B-20 Initial Moisture Content (%)3
Sample Number:---Final Moisture Content (%)15
Depth (ft)5 to 6 Initial Dry Density (pcf)116.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)123.0
Specimen Thickness (in)1.0 Percent Collapse (%)1.27
Proposed Commercial/Industrial Building
Fontana, CA
Project No. 19G241-3
PLATE C- 2
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Light Gray Brown fine to coarse Sand, trace Silt
Boring Number:B-20 Initial Moisture Content (%)3
Sample Number:---Final Moisture Content (%)11
Depth (ft)7 to 8 Initial Dry Density (pcf)123.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)130.3
Specimen Thickness (in)1.0 Percent Collapse (%)0.82
Proposed Commercial/Industrial Building
Fontana, CA
Project No. 19G241-3
PLATE C- 3
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Light Gray Brown fine to coarse Sand, trace Silt
Boring Number:B-20 Initial Moisture Content (%)3
Sample Number:---Final Moisture Content (%)11
Depth (ft)9 to 10 Initial Dry Density (pcf)117.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)122.5
Specimen Thickness (in)1.0 Percent Collapse (%)0.74
Proposed Commercial/Industrial Building
Fontana, CA
Project No. 19G241-3
PLATE C- 4
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Proposed Commercial/Industrial Building
Fontana, CA
Project No. 19G241-3
PLATE C-5
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
0 2 4 6 8 10 12 14
Dry
Density
(lbs/ft3)
Moisture Content (%)
Moisture/Density Relationship
ASTM D-1557
Soil ID Number B-20 @ 0-5'
Optimum Moisture (%)6.5
Maximum Dry Density (pcf)130.5
Soil
Classification
Dark Brown Silty fine Sand, little
medium to coarse Sand, trace fine
Gravel
Zero Air Voids Curve:
Specific Gravity = 2.7
Grading Guide Specifications Page 1
GRADING GUIDE SPECIFICATIONS
These grading guide specifications are intended to provide typical procedures for grading operations.
They are intended to supplement the recommendations contained in the geotechnical investigation
report for this project. Should the recommendations in the geotechnical investigation report conflict
with the grading guide specifications, the more site specific recommendations in the geotechnical
investigation report will govern.
General
• The Earthwork Contractor is responsible for the satisfactory completion of all earthwork in
accordance with the plans and geotechnical reports, and in accordance with city, county,
and applicable building codes.
• The Geotechnical Engineer is the representative of the Owner/Builder for the purpose of
implementing the report recommendations and guidelines. These duties are not intended to
relieve the Earthwork Contractor of any responsibility to perform in a workman-like manner,
nor is the Geotechnical Engineer to direct the grading equipment or personnel employed by
the Contractor.
• The Earthwork Contractor is required to notify the Geotechnical Engineer of the anticipated
work and schedule so that testing and inspections can be provided. If necessary, work may
be stopped and redone if personnel have not been scheduled in advance.
• The Earthwork Contractor is required to have suitable and sufficient equipment on the job-
site to process, moisture condition, mix and compact the amount of fill being placed to the
approved compaction. In addition, suitable support equipment should be available to
conform with recommendations and guidelines in this report.
• Canyon cleanouts, overexcavation areas, processed ground to receive fill, key excavations,
subdrains and benches should be observed by the Geotechnical Engineer prior to placement
of any fill. It is the Earthwork Contractor's responsibility to notify the Geotechnical Engineer
of areas that are ready for inspection.
• Excavation, filling, and subgrade preparation should be performed in a manner and
sequence that will provide drainage at all times and proper control of erosion. Precipitation,
springs, and seepage water encountered shall be pumped or drained to provide a suitable
working surface. The Geotechnical Engineer must be informed of springs or water seepage
encountered during grading or foundation construction for possible revision to the
recommended construction procedures and/or installation of subdrains.
Site Preparation
• The Earthwork Contractor is responsible for all clearing, grubbing, stripping and site
preparation for the project in accordance with the recommendations of the Geotechnical
Engineer.
• If any materials or areas are encountered by the Earthwork Contractor which are suspected
of having toxic or environmentally sensitive contamination, the Geotechnical Engineer and
Owner/Builder should be notified immediately.
Grading Guide Specifications Page 2
• Major vegetation should be stripped and disposed of off-site. This includes trees, brush,
heavy grasses and any materials considered unsuitable by the Geotechnical Engineer.
• Underground structures such as basements, cesspools or septic disposal systems, mining
shafts, tunnels, wells and pipelines should be removed under the inspection of the
Geotechnical Engineer and recommendations provided by the Geotechnical Engineer and/or
city, county or state agencies. If such structures are known or found, the Geotechnical
Engineer should be notified as soon as possible so that recommendations can be
formulated.
• Any topsoil, slopewash, colluvium, alluvium and rock materials which are considered
unsuitable by the Geotechnical Engineer should be removed prior to fill placement.
• Remaining voids created during site clearing caused by removal of trees, foundations
basements, irrigation facilities, etc., should be excavated and filled with compacted fill.
• Subsequent to clearing and removals, areas to receive fill should be scarified to a depth of
10 to 12 inches, moisture conditioned and compacted
• The moisture condition of the processed ground should be at or slightly above the optimum
moisture content as determined by the Geotechnical Engineer. Depending upon field
conditions, this may require air drying or watering together with mixing and/or discing.
Compacted Fills
• Soil materials imported to or excavated on the property may be utilized in the fill, provided
each material has been determined to be suitable in the opinion of the Geotechnical
Engineer. Unless otherwise approved by the Geotechnical Engineer, all fill materials shall be
free of deleterious, organic, or frozen matter, shall contain no chemicals that may result in
the material being classified as “contaminated,” and shall be very low to non-expansive with
a maximum expansion index (EI) of 50. The top 12 inches of the compacted fill should
have a maximum particle size of 3 inches, and all underlying compacted fill material a
maximum 6-inch particle size, except as noted below.
• All soils should be evaluated and tested by the Geotechnical Engineer. Materials with high
expansion potential, low strength, poor gradation or containing organic materials may
require removal from the site or selective placement and/or mixing to the satisfaction of the
Geotechnical Engineer.
• Rock fragments or rocks less than 6 inches in their largest dimensions, or as otherwise
determined by the Geotechnical Engineer, may be used in compacted fill, provided the
distribution and placement is satisfactory in the opinion of the Geotechnical Engineer.
• Rock fragments or rocks greater than 12 inches should be taken off-site or placed in
accordance with recommendations and in areas designated as suitable by the Geotechnical
Engineer. These materials should be placed in accordance with Plate D-8 of these Grading
Guide Specifications and in accordance with the following recommendations:
• Rocks 12 inches or more in diameter should be placed in rows at least 15 feet apart, 15
feet from the edge of the fill, and 10 feet or more below subgrade. Spaces should be
left between each rock fragment to provide for placement and compaction of soil
around the fragments.
• Fill materials consisting of soil meeting the minimum moisture content requirements and
free of oversize material should be placed between and over the rows of rock or
Grading Guide Specifications Page 3
concrete. Ample water and compactive effort should be applied to the fill materials as
they are placed in order that all of the voids between each of the fragments are filled
and compacted to the specified density.
• Subsequent rows of rocks should be placed such that they are not directly above a row
placed in the previous lift of fill. A minimum 5-foot offset between rows is
recommended.
• To facilitate future trenching, oversized material should not be placed within the range
of foundation excavations, future utilities or other underground construction unless
specifically approved by the soil engineer and the developer/owner representative.
• Fill materials approved by the Geotechnical Engineer should be placed in areas previously
prepared to receive fill and in evenly placed, near horizontal layers at about 6 to 8 inches in
loose thickness, or as otherwise determined by the Geotechnical Engineer for the project.
• Each layer should be moisture conditioned to optimum moisture content, or slightly above,
as directed by the Geotechnical Engineer. After proper mixing and/or drying, to evenly
distribute the moisture, the layers should be compacted to at least 90 percent of the
maximum dry density in compliance with ASTM D-1557-78 unless otherwise indicated.
• Density and moisture content testing should be performed by the Geotechnical Engineer at
random intervals and locations as determined by the Geotechnical Engineer. These tests
are intended as an aid to the Earthwork Contractor, so he can evaluate his workmanship,
equipment effectiveness and site conditions. The Earthwork Contractor is responsible for
compaction as required by the Geotechnical Report(s) and governmental agencies.
• Fill areas unused for a period of time may require moisture conditioning, processing and
recompaction prior to the start of additional filling. The Earthwork Contractor should notify
the Geotechnical Engineer of his intent so that an evaluation can be made.
• Fill placed on ground sloping at a 5-to-1 inclination (horizontal-to-vertical) or steeper should
be benched into bedrock or other suitable materials, as directed by the Geotechnical
Engineer. Typical details of benching are illustrated on Plates D-2, D-4, and D-5.
• Cut/fill transition lots should have the cut portion overexcavated to a depth of at least 3 feet
and rebuilt with fill (see Plate D-1), as determined by the Geotechnical Engineer.
• All cut lots should be inspected by the Geotechnical Engineer for fracturing and other
bedrock conditions. If necessary, the pads should be overexcavated to a depth of 3 feet
and rebuilt with a uniform, more cohesive soil type to impede moisture penetration.
• Cut portions of pad areas above buttresses or stabilizations should be overexcavated to a
depth of 3 feet and rebuilt with uniform, more cohesive compacted fill to impede moisture
penetration.
• Non-structural fill adjacent to structural fill should typically be placed in unison to provide
lateral support. Backfill along walls must be placed and compacted with care to ensure that
excessive unbalanced lateral pressures do not develop. The type of fill material placed
adjacent to below grade walls must be properly tested and approved by the Geotechnical
Engineer with consideration of the lateral earth pressure used in the design.
Grading Guide Specifications Page 4
Foundations
• The foundation influence zone is defined as extending one foot horizontally from the outside
edge of a footing, and proceeding downward at a ½ horizontal to 1 vertical (0.5:1)
inclination.
• Where overexcavation beneath a footing subgrade is necessary, it should be conducted so
as to encompass the entire foundation influence zone, as described above.
• Compacted fill adjacent to exterior footings should extend at least 12 inches above
foundation bearing grade. Compacted fill within the interior of structures should extend to
the floor subgrade elevation.
Fill Slopes
• The placement and compaction of fill described above applies to all fill slopes. Slope
compaction should be accomplished by overfilling the slope, adequately compacting the fill
in even layers, including the overfilled zone and cutting the slope back to expose the
compacted core
• Slope compaction may also be achieved by backrolling the slope adequately every 2 to 4
vertical feet during the filling process as well as requiring the earth moving and compaction
equipment to work close to the top of the slope. Upon completion of slope construction,
the slope face should be compacted with a sheepsfoot connected to a sideboom and then
grid rolled. This method of slope compaction should only be used if approved by the
Geotechnical Engineer.
• Sandy soils lacking in adequate cohesion may be unstable for a finished slope condition and
therefore should not be placed within 15 horizontal feet of the slope face.
• All fill slopes should be keyed into bedrock or other suitable material. Fill keys should be at
least 15 feet wide and inclined at 2 percent into the slope. For slopes higher than 30 feet,
the fill key width should be equal to one-half the height of the slope (see Plate D-5).
• All fill keys should be cleared of loose slough material prior to geotechnical inspection and
should be approved by the Geotechnical Engineer and governmental agencies prior to filling.
• The cut portion of fill over cut slopes should be made first and inspected by the
Geotechnical Engineer for possible stabilization requirements. The fill portion should be
adequately keyed through all surficial soils and into bedrock or suitable material. Soils
should be removed from the transition zone between the cut and fill portions (see Plate D-
2).
Cut Slopes
• All cut slopes should be inspected by the Geotechnical Engineer to determine the need for
stabilization. The Earthwork Contractor should notify the Geotechnical Engineer when slope
cutting is in progress at intervals of 10 vertical feet. Failure to notify may result in a delay
in recommendations.
• Cut slopes exposing loose, cohesionless sands should be reported to the Geotechnical
Engineer for possible stabilization recommendations.
• All stabilization excavations should be cleared of loose slough material prior to geotechnical
inspection. Stakes should be provided by the Civil Engineer to verify the location and
dimensions of the key. A typical stabilization fill detail is shown on Plate D-5.
Grading Guide Specifications Page 5
• Stabilization key excavations should be provided with subdrains. Typical subdrain details
are shown on Plates D-6.
Subdrains
• Subdrains may be required in canyons and swales where fill placement is proposed. Typical
subdrain details for canyons are shown on Plate D-3. Subdrains should be installed after
approval of removals and before filling, as determined by the Soils Engineer.
• Plastic pipe may be used for subdrains provided it is Schedule 40 or SDR 35 or equivalent.
Pipe should be protected against breakage, typically by placement in a square-cut
(backhoe) trench or as recommended by the manufacturer.
• Filter material for subdrains should conform to CALTRANS Specification 68-1.025 or as
approved by the Geotechnical Engineer for the specific site conditions. Clean ¾-inch
crushed rock may be used provided it is wrapped in an acceptable filter cloth and approved
by the Geotechnical Engineer. Pipe diameters should be 6 inches for runs up to 500 feet
and 8 inches for the downstream continuations of longer runs. Four-inch diameter pipe
may be used in buttress and stabilization fills.
GRADING GUIDE SPECIFICATIONS
NOT TO SCALE
DRAWN: JAS
CHKD: GKM
PLATE D-2
FILL ABOVE CUT SLOPE DETAIL
9' MIN.
4' TYP.
MINIMUM 1' TILT BACK
OR 2% SLOPE
(WHICHEVER IS GREATER)
REMOVE U
N
S
U
I
T
A
B
L
E
M
A
T
E
R
I
A
L
BENCHING DIMENSIONS IN ACCORDANCE
WITH PLAN OR AS RECOMMENDED
BY THE GEOTECHNICAL ENGINEER
CUT SLOPE TO BE CONSTRUCTED
PRIOR TO PLACEMENT OF FILL
BEDROCK OR APPROVED
COMPETENT MATERIAL
CUT SLOPE
NATURAL GRADE
CUT/FILL CONTACT TO BE
SHOWN ON "AS-BUILT"
COMPETENT MATERIAL CUT/FILL CONTACT SHOWN
ON GRADING PLAN
NEW COMPACTED FILL
10' TYP.
KEYWAY IN COMPETENT MATERIAL
MINIMUM WIDTH OF 15 FEET OR AS
RECOMMENDED BY THE GEOTECHNICAL
ENGINEER. KEYWAY MAY NOT BE
REQUIRED IF FILL SLOPE IS LESS THAN 5
FEET IN HEIGHT AS RECOMMENDED BY
THE GEOTECHNICAL ENGINEER.
GRADING GUIDE SPECIFICATIONS
NOT TO SCALE
DRAWN: JAS
CHKD: GKM
PLATE D-4
FILL ABOVE NATURAL SLOPE DETAIL
10' TYP.4' TYP.
(WHICHEVER IS GREATER)
OR 2% SLOPE
MINIMUM 1' TILT BACK
REMOVE UN
S
U
I
T
A
B
L
E
M
A
T
E
R
I
A
L
NEW COMPACTED FILL
COMPETENT MATERIAL
KEYWAY IN COMPETENT MATERIAL.
RECOMMENDED BY THE GEOTECHNIAL
ENGINEER. KEYWAY MAY NOT BE REQUIRED
IF FILL SLOPE IS LESS THAN 5' IN HEIGHT
AS RECOMMENDED BY THE GEOTECHNICAL
ENGINEER.
2' MINIMUM
KEY DEPTH
OVERFILL REQUIREMENTS
PER GRADING GUIDE SPECIFICATIONS
TOE OF SLOPE SHOWN
ON GRADING PLAN
BACKCUT - VARIES
PLACE COMPACTED BACKFILL
TO ORIGINAL GRADE
PROJECT SLOPE GRADIENT
(1:1 MAX.)
NOTE:
BENCHING SHALL BE REQUIRED
WHEN NATURAL SLOPES ARE
EQUAL TO OR STEEPER THAN 5:1
OR WHEN RECOMMENDED BY
THE GEOTECHNICAL ENGINEER.
FINISHED SLOPE FACE
MINIMUM WIDTH OF 15 FEET OR AS
BENCHING DIMENSIONS IN ACCORDANCE
WITH PLAN OR AS RECOMMENDED
BY THE GEOTECHNICAL ENGINEER
GRADING GUIDE SPECIFICATIONS
NOT TO SCALE
DRAWN: JAS
CHKD: GKM
PLATE D-5
STABILIZATION FILL DETAIL
FACE OF FINISHED SLOPE
COMPACTED FILL
MINIMUM 1' TILT BACK
OR 2% SLOPE
(WHICHEVER IS GREATER)
10' TYP.
2' MINIMUM
KEY DEPTH
3' TYPICAL
BLANKET FILL IF RECOMMENDED
BY THE GEOTECHNICAL ENGINEER
COMPETENT MATERIAL ACCEPTABLE
TO THE SOIL ENGINEER
KEYWAY WIDTH, AS SPECIFIED
BY THE GEOTECHNICAL ENGINEER
TOP WIDTH OF FILL
AS SPECIFIED BY THE
GEOTECHNICAL ENGINEER
BENCHING DIMENSIONS IN ACCORDANCE
WITH PLAN OR AS RECOMMENDED
BY THE GEOTECHNICAL ENGINEER
4' TYP.
PROPOSED COMMERCIAL/INDUSTRIAL BUILDING
DRAWN: RB
CHKD: RGT
SCG PROJECT
19G241-3
PLATE E-1
SEISMIC DESIGN PARAMETERS - 2019 CBC
FONTANA, CALIFORNIA
SOURCE: SEAOC/OSHPD Seismic Design Maps Tool
<https://seismicmaps.org/>
12
15
11
28
41
17
36
7
2
12
5
1
7
3
FILL: Dark Brown Silty fine Sand, trace medium to coarse
Sand, trace fine Gravel, medium dense-damp to moist
ALLUVIUM: Light Gray Brown Gravelly fine to coarse Sand,
trace Silt, medium dense-dry to damp
Brown Silty fine Sand to fine Sandy Silt, trace medium Sand,
medium dense-moist
Brown Silty fine Sand, trace medium to coarse Sand, trace
fine Gravel, medium dense-damp
Gray Gravelly fine to coarse Sand, trace Silt, dense-dry
Brown Silty fine Sand, trace medium to coarse Sand, medium
dense-damp to moist
Gray Brown Gravelly fine to coarse Sand, trace Silt,
dense-damp
Boring Terminated at 25'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-1
PLATE B-1
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 11 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
25
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
26
57
58
24
26
22
52
117
111
117
6
3
3
3
2
2
3± inches Asphaltic concrete, 4± inches Aggregate base
FILL: Dark Brown Silty fine Sand, trace medium to coarse
Sand, little fine Gravel, medium dense-damp
POSSIBLE FILL: Brown to Gray Brown Silty fine to medium
Sand, trace to little coarse Sand, trace fine Gravel, medium
dense to dense-damp
ALLUVIUM: Gray Brown fine to coarse Sand, little fine Gravel,
medium dense-damp
Gray Gravelly fine to coarse Sand, trace Silt, very dense-dry to
damp
Boring Terminated at 20'
No Sample
Recovery
Disturbed
Sample
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-2
PLATE B-2
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 11 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
19
9
20
22
25
22
5
8
3
2
1
7
2± inches Asphaltic concrete, 4± inches Aggregate base
ALLUVIUM: Brown Silty fine Sand, trace medium to coarse
Sand, loose to medium dense-damp to moist
Gray to Gray Brown fine to medium Sand, trace to little Silt,
trace to little coarse Sand, trace to little fine Gravel, medium
dense-damp
Gray Gravelly fine to coarse Sand, medium dense-dry
Brown Silty fine Sand, little medium to coarse Sand, medium
dense-damp to moist
Boring Terminated at 20'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-3
PLATE B-3
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 13 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
25
20
30
14
17
37
29
114
103
118
108
108
4
2
1
6
14
3
7
ALLUVIUM: Light Brown Silty fine to medium Sand, trace
coarse Sand, medium dense-damp
Gray to Gray Brown fine to medium Sand, trace to little coarse
Sand, trace to little fine Gravel, loose to medium dense-dry to
damp
Light Brown Silty fine Sand to fine Sandy Silt, trace medium
Sand, loose to medium dense-damp to very moist
Gray Brown fine to medium Sand, trace Silt, little coarse Sand,
trace fine Gravel, dense-damp
Brown Silty fine Sand, little medium to coarse Sand, trace fine
Gravel, medium dense-damp to moist
Boring Terminated at 20'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-4
PLATE B-4
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 13 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
9
26
26
38
40
18
40
116
109
108
113
121
11
3
6
2
1
7
2
FILL: Dark Brown Silty fine Sand, trace medium to coarse
Sand, mottled, loose-moist to very moist
FILL: Brown to Gray Brown fine to coarse Sand, little Silt,
trace to little coarse Sand, trace fine Gravel, medium
dense-damp
FILL: Brown Silty fine Sand, trace medium to coarse Sand,
trace fine to coarse Gravel, medium dense-damp to moist
ALLUVIUM: Gray Brown to Gray Gravelly fine to coarse Sand,
trace Silt, medium dense-dry to damp
Gray Brown Silty fine Sand, trace medium to coarse Sand,
medium dense-damp to moist
Gray Gravelly fine to coarse Sand, trace Silt, dense-dry to
damp
Boring Terminated at 20'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-5
PLATE B-5
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 14 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
40
24
16
13
10
11
20
7
6
2
3
7
10
10
2± inches Asphaltic concrete, 5± inches Aggregate base
FILL: Brown to Dark Brown Silty fine Sand, trace medium to
coarse Sand, trace fine Gravel, mottled, medium dense to
dense-damp to moist
ALLUVIUM: Brown to Gray Brown fine to coarse Sand, trace
to little Silt, trace to little fine Gravel, medium dense-damp
Gray Silty fine Sand, medium dense-moist
Brown fine Sandy Silt, medium dense-moist
Boring Terminated at 25'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-6
PLATE B-6
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 18 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
25
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
49
39
35
81
64
117
122
125
113
5
2
1
1
1
2± inches Asphaltic concrete, 5± inches Aggregate base
FILL: Brown Silty fine Sand, trace medium to coarse Sand,
trace fine Gravel, dense-damp
POSSIBLE FILL: Brown fine to medium Sand, trace coarse
Sand, little Silt, trace fine Gravel, medium dense-dry to damp
ALLUVIUM: Gray Gravelly fine to coarse Sand, trace Silt,
medium dense to very dense-dry to damp
Boring Terminated at 10'
Disturbed
Sample
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-7
PLATE B-7
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 4 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
14
20
23
16
39
49
5
3
2
3
2
3
ALLUVIUM: Brown fine to medium Sand, trace coarse Sand,
medium dense-damp
Gray Brown Silty fine Sand, trace medium to coarse Sand,
trace to little fine to coarse Gravel, medium dense-damp
Gray Brown fine to medium Sand, trace coarse Sand, trace
fine Gravel, medium dense-damp
Gray Gravelly fine to coarse Sand, trace Silt, dense-dry to
damp
Boring Terminated at 20'
JOB NO.: 19G241-1
PROJECT: Proposed Warehouse
LOCATION: Fontana, California
BORING NO.
B-8
PLATE B-8
DRILLING DATE: 12/11/19
DRILLING METHOD: Hollow Stem Auger
LOGGED BY: Ross Kovtun
FIELD RESULTS
PO
C
K
E
T
P
E
N
.
(T
S
F
)
LABORATORY RESULTS
CO
M
M
E
N
T
S
SURFACE ELEVATION: --- MSL DR
Y
D
E
N
S
I
T
Y
(P
C
F
)
DE
P
T
H
(
F
E
E
T
)
MO
I
S
T
U
R
E
CO
N
T
E
N
T
(
%
)
LI
Q
U
I
D
LI
M
I
T
PL
A
S
T
I
C
LI
M
I
T
SA
M
P
L
E
BL
O
W
C
O
U
N
T
WATER DEPTH: Dry
CAVE DEPTH: 10 feet
READING TAKEN: At Completion
OR
G
A
N
I
C
CO
N
T
E
N
T
(
%
)
5
10
15
20
GR
A
P
H
I
C
L
O
G
PA
S
S
I
N
G
#2
0
0
S
I
E
V
E
(
%
)
TEST BORING LOG
DESCRIPTION
TB
L
1
9
G
2
4
1
-
1
.
G
P
J
S
O
C
A
L
G
E
O
.
G
D
T
1
/
1
5
/
2
0
Classification: Gray to Gray Brown fine to medium Sand, trace to little coarse Sand
Boring Number:B-4 Initial Moisture Content (%)2
Sample Number:---Final Moisture Content (%)20
Depth (ft)3 to 4 Initial Dry Density (pcf)103.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)107.2
Specimen Thickness (in)1.0 Percent Collapse (%)0.14
Proposed Warehouse
Fontana, CA
Project No. 19G241-1
PLATE C- 1
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Gray to Gray Brown fine to medium Sand, trace to little coarse Sand
Boring Number:B-4 Initial Moisture Content (%)1
Sample Number:---Final Moisture Content (%)17
Depth (ft)5 to 6 Initial Dry Density (pcf)118.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)127.6
Specimen Thickness (in)1.0 Percent Collapse (%)2.14
Proposed Warehouse
Fontana, CA
Project No. 19G241-1
PLATE C- 2
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Light Brown Silty fine Sand to fine Sandy Silt
Boring Number:B-4 Initial Moisture Content (%)6
Sample Number:---Final Moisture Content (%)24
Depth (ft)7 to 8 Initial Dry Density (pcf)108.0
Specimen Diameter (in)2.4 Final Dry Density (pcf)112.0
Specimen Thickness (in)1.0 Percent Collapse (%)0.00
Proposed Warehouse
Fontana, CA
Project No. 19G241-1
PLATE C- 3
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Classification: Light Brown Silty fine Sand to fine Sandy Silt
Boring Number:B-4 Initial Moisture Content (%)14
Sample Number:---Final Moisture Content (%)22
Depth (ft)9 to 10 Initial Dry Density (pcf)107.7
Specimen Diameter (in)2.4 Final Dry Density (pcf)112.2
Specimen Thickness (in)1.0 Percent Collapse (%)0.20
Proposed Warehouse
Fontana, CA
Project No. 19G241-1
PLATE C- 4
0
2
4
6
8
10
12
14
16
18
20
0.1 1 10 100
Consolidation
Strain
(%)
Load (ksf)
Consolidation/Collapse Test Results
Water Added
at 1600 psf
Proposed Warehouse
Fontana, CA
Project No. 19G241-1
PLATE C-5
114
116
118
120
122
124
126
128
130
132
134
136
4 6 8 10 12 14 16 18
Dry
Density
(lbs/ft3)
Moisture Content (%)
Moisture/Density Relationship
ASTM D-1557
Soil ID Number B-1 @ 0-5'
Optimum Moisture (%)8
Maximum Dry Density (pcf)132.5
Soil Dark Gray Brown Silty fine Sand,
Classification trace medium to coarse Sand,
trace fine Gravel
Zero Air Voids Curve:
Specific Gravity = 2.7