HomeMy WebLinkAboutW.O. 2588-A-SC; Carnation/Fernandez Property-Spectrum Communities; Carnation/Fernandez Property; 1998-12-03I
* PRELIMINARY GEOTECHNICAL INVESTIGATION
- 10-ACRE "CARNATION/FERNANDEZ PROPERTY"
I CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA
I FOR
. ' ' - V ' .; -. '.: : •• -.:••
SPECTRUM COMMUNITIES
• 15375 BARRANCA PARKWAY
I IRVINE, CALIFORNIA 92618
P W.0. 2588-A-SC DECEMBER 3, 1998
Geotechnical • Geologic • Environmental
5741 Palmer Way • Carlsbad, California 92008 • (760)438-3155 • FAX (760) 931-0915
Decembers, 1998
W.O. 2588-A-SC
Spectrum Communities
15375 Barranca Parkway, Suite B-211
Irvine, California 92618
Attention: Mr. David Salene
Subject: Preliminary Geotechnical Investigation, 10-Acre "Carnation/Fernandez
Property," Carlsbad, San Diego County, California
Dear Mr. Jones:
In accordance with your request, GeoSoils, Inc. (GSI) is pleased to present the results of
our preliminary geotechnical investigation on the subject site. The purpose of our
investigation was to evaluate the geologic and geotechnical conditions of the site, relative
to the proposed development, and present recommendations for grading and foundation
design and construction for the proposed development.
EXECUTIVE SUMMARY
Based on our field exploration, geologic and geotechnical engineering analysis, the
proposed development appears feasible from a soils engineering and geologic viewpoint,
provided that the recommendations presented in the text of this report are properly
incorporated into the design and construction of the project. The most significant elements
of our study are summarized below:
• The existing fill (undocumented) materials encountered locally over portions of the
site range from about 1 to 5 feet thick and appear to be generally non-uniform and
below the current industry minimum standard. Recommendations for the treatment
of existing fills are presented in the earthwork section of this report.
• Topsoil/colluvium materials underlying portions of the site are generally moist,
loose, and porous and/or do not meet the current industry minimum standards.
Recommendations for the treatment of topsoil/colluvium are presented in the
earthwork section of this report.
Formationai materials will also be encountered during site earthwork. These
materials are considered competent to support settlement-sensitive structures in
their existing state.
• The site materials have a negligible to low sulfate exposure for corrosion to
concrete, are neutral to slightly acidic, and have a high potential for corrosion to
ferrous metals.
Soils with a very low expansion potential underlie the site. This should be
considered during project design.
• Subsurface and surface water are not anticipated to affect site development,
provided that the recommendations contained in this report are incorporated into
final design and construction, and that prudent surface and subsurface drainage
practices are incorporated into the construction plans. Perched groundwater
conditions along fill/bedrock contacts and along zones of contrasting permeabilities
should not be precluded from occurring in the future due to site irrigation, poor
drainage conditions, or damaged utilities.
• The seismic acceleration values provided herein should be considered during the
design of the proposed development.
• The geotechnical design parameters provided herein should be considered during
construction by the project structural engineer and/or architect.
We appreciate the opportunity to be of service. If you have any questions pertaining to this
report, please contact us at (760) 438-3155.
Respectfully submitted,
GeoSoils, Inc.
Sherry L Eaton
Senior Geologist
in P. Franklin
^gineering Geologist,
SLE/RGC/JPF/DWS/mo
Distribution: (2) Addressee
David W. Skelly
Civil Engineer, RCE 4
(2) Jacfc Henthom & Associates, Attention: Mr. Jack Henthom
Spectrum Communities
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W.O. 2588-A-SC
Page Two
TABLE OF CONTENTS
SCOPE OF SERVICES 1
SITE DESCRIPTION 1
PROPOSED DEVELOPMENT 3
FIELD STUDIES 3
REGIONAL GEOLOGY 3
EARTH MATERIALS 3
Artificial Fill - Undocumented (Unmapped) 4
Topsoil/Colluviurn (Unmapped) 4
Lindavista Formation (Map Symbol - Qlv) 4
Santiago Formation (Map Symbol - Tsb) 5
FAULTING AND REGIONAL SEISMICITY 5
Faulting 5
Seismicity 5
Seismic Shaking Parameters 5
GROUNDWATER 7-
LABORATORY TESTING 7
Classification 7
Laboratory Standard 8
Expansion Index Testing 8
Shear Testing 8
Corrosion 9
DISCUSSION AND CONCLUSIONS 9
General 9
Earth Materials 10
Corrosivity 10
Expansion Potential 10
Subsurface and Surface Water 10
Regional Seismic Activity 11
EARTHWORK CONSTRUCTION RECOMMENDATIONS 11
General 11
Site Preparation 11
Removals (Unsuitable Surficial Materials) 11
Overexcavation 12
Fill Placement 12
Slope Considerations and Slope Design 13
GeoSoils, Inc.
RECOMMENDATIONS - FOUNDATIONS 13
Preliminary Foundation Design 13
Foundation Construction 14
FOOTING SETBACKS 15
CORROSION AND CONCRETE MIX 15
RETAINING WALL RECOMMENDATIONS 15
General 15
Restrained Walls 16
Cantilevered Walls 16
Wall Backfill and Drainage 17
Retaining Wall Footing Transitions 17
FLATWORK AND ASSOCIATED IMPROVEMENTS 21
Tile Flooring 22
Gutters and Downspouts 22
Exterior Slabs and Walkways 22
ADDITIONAL RECOMMENDATIONS/DEVELOPMENT CRITERIA 23
Additional Site Improvements 23
Erosion and Sedimentation Control 23
Landscape Maintenance and Planting 23
Drainage 24
Footing Trench Excavation 24
Trench Backfill 25
TRENCH BACKFILL 25
PLAN REVIEW 25
INVESTIGATION LIMITATIONS 26
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GeoSoils, Inc.
PRELIMINARY GEOTECHNICAL INVESTIGATION
10-ACRE "CARNATION/FERNANDEZ PROPERTY"
CARLSBAD, SAN DIEGO COUNTY, CALIFORNIA
SCOPE OF SERVICES
The scope of our services has included the following:
1. Review of readily available published literature and maps of the vicinity, including
review of stereoscopic aerial photographs (Appendix A).
2. Subsurface exploration consisting of hand-augering of 10 exploratory borings to
determine the soil/bedrock profiles, obtain relatively undisturbed and bulk samples
of representative materials, and delineate earth material parameters that may affect
the stability of the existing bluff and the proposed development.
3. Laboratory testing of representative soil samples collected during our subsurface
exploration program.
4. Evaluation of potential areal seismicrty and secondary seismic hazards.
5. Appropriate engineering and geologic analyses of data collected, and preparation
of this report and accompaniments
SITE DESCRIPTION
The subject site is a parcel, consisting of about 10 acres, located on Black Rail Road in
Carlsbad, San Diego County, California (see Site Location Map, Figure 1). The site is
bounded on the north by agricultural nurseries, on the west by a housing tract and an
undeveloped canyon, on the south by undeveloped property (previously agricultural), and
on the east by Black Rail Road. The site, which overall slopes in an westerly direction, is
situated on an irregular mesa. Elevations onsite range from roughly 375 feet MSL in the
northeastern corner of the site, to approximately 314 feet MSL in the southwest corner of
the site. Drainage is generally to the southwest.
The site is currently occupied by an agricultural nursery. Structures on the site consist of
greenhouses and related structures, storage facilities, and single-family houses.
Stockpiles of materials were observed on the site, which included construction materials,
construction waste materials, agricultural waste materials, and earth materials. Also
observed on the site were abandoned vehicles, above ground storage tanks, and
"outhouse" restroom facilities.
GeoSoils, Inc.
Base Map: Encinitas Quadrangle, California—San Diego Co., 7.5 Minute Series (Topographic),
1968 (photo revised 1975), by USGS, 1"=2000'
Base Map: The Thomas Guide, San Diego County Street Guide and Directory, 1998 Edition, by
Thomas Bros. Maps, page 1127, 1"=1/2 mile
Reproduced with permission granted by Thorn** Bros. MfP«- .-ThU nap to copyrighted ky Thoma* Brom. Mipe. Jl to P<mvriil
to MMor reproduce * •riny paHjtonof. «»•*•'-*>« •personal use or resale, without permission. M rights reserved.
W.O.
2588-A-SC
SITE LOCATION MAP
Figure 1
PROPOSED DEVELOPMENT
It is our understanding that the proposed development would consist of cut-and-fill grading
to create lots for the proposed development, which would consist of residential tract
construction and associated utility, street, and landscape improvements. It is also our
understanding that the buildings would be one- or two-story structures, utilizing wood-
frame or masonry-block construction with continuous footings and slab-on-grade floors.
Building loads are assumed to be typical for this type of relatively light construction.
Sewage disposal would tie into the municipal system.
FIELD STUDIES
Field studies conducted during our evaluation of the property for this study consisted of
geologic reconnaissance, geologic mapping, and excavation of 10 hand-auger exploratory
borings for evaluation of near-surface soil and geologic materials. The borings were
logged by a geologist from our firm, who collected representative bulk samples from the
excavations for appropriate laboratory testing. The logs of the borings are presented in
Appendix B, and the locations of the borings are presented on Plate 1.
REGIONAL GEOLOGY
The subject property is located within a prominent natural geomorphic province in
southwestern California known as the Peninsular Ranges. It is characterized by steep,
elongated mountain ranges and valleys that trend northwesterly. The mountain ranges are
underlain by basement rocks consisting of pre-Cretaceous metasedimentary rocks,
Jurassic metavolcanic rocks, and Cretaceous plutonic rocks of the southern California
batholith.
In the San Diego region, deposition occurred during the Cretaceous period and Cenozoic
era in the continental margin of a forearc basin. Sediments, derived from Cretaceous-aged
plutonic rocks and Jurassic-age volcanic rocks, were deposited into the narrow, steep,
coastal plain and continental margin of the basin. These rocks have been eroded and
deeply incised. These younger sediments are now locally exposed at the surface.
EARTH MATERIALS
Earth materials encountered on the site consist of undocumented artificial fill, colluvium,
the Lindavista Formation, and the Santiago Formation.
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Artificial FIN - Undocumented (Unmapped)
Undocumented artificial fill materials associated with the agricultural cultivation were
encountered in our borings B-3, B-4, B-6, B-7, B-8, B-9, and B-10, underlying portions of
the site. Based on our observations, the fill materials are estimated to range from about
1 to 5 feet in thickness (but may be thicker) in localized areas throughout the site. The fill
materials consisted of orangish brown and brownish orange, silty sands. These materials
generally were moist and loose to medium dense. Owing to the lack of documentation of
their placement, non-homogeneous nature, and consistency, the undocumented fill soils
are considered potentially compressible in their present state and unsuitable for support
of settlement-sensitive structures.
Topsoil/Colluvium (Unmapped)
Topsoil/colluvium underlies portions of the sfte at the surface. The topsoil/colluvial
materials encountered onsite consisted of brown to reddish brown, silty sands. The
materials generally were damp, loose, and porous. These materials generally were about
1 foot thick. The colluvial soils are considered potentially compressible in their present
state and unsuitable for support of settlement-sensitive structures.
Lindavista Formation (Map Symbol - Qiv)
The site is underlain in the near-surface by terrace deposits of the Linda Vista Formation,
mapped by Wilson (1972). The formational materials generally consist of yellowish
orangish brown, silty sandstone. The materials were moist and medium dense. Mapping
of these materials (Wilson, 1972) indicates a generally massively bedded trend for this
geologic unit.
Santiago Formation (Map Symbol - Tsb)
The entire site is underlain at depth by the Santiago Formation, mapped by Wilson (1972).
The Santiago Formation was encountered in our boring B-10 at a depth of about 21/2 feet.
These materials generally consist of grayish brown, silty sandstone. The materials were
moist and dense. This fades of the Santiago Formation generally has a very low to low
expansion potential; however, other facies wrthin the Santiago Formation may have a
medium to high expansion potential.
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FAULTING AND REGIONAL SEISMICITY
Faulting
The site is situated in an area of active as well as potentially-active faults. Our review
indicates that there are no known active faults crossing the site within the areas proposed
for development (Jennings, 1994; Wilson, 1972), and the site is not within an Alquist-Priolo
Earthquake Fault Zone (Hart, 1997).
There are a number of faults in the southern California area that are considered active and
would have an effect on the site in the form of ground shaking, should they be the source
of an earthquake. These include-but are not limited to-the San Andreas fault, the San
Jacinto fault, the Elsinore fault, the Coronado Bank fault zone, and the
Newport-lnglewood/Rose Canyon fault zone. The location of these and other major faults
relative to the site are indicated on Figure 2. The possibility of ground acceleration or
shaking at the site may be considered as approximately similar to the southern California
region as a whole.
Seismicity
The acceleration-attenuation relations of Joyner and Boore (1982), Campbell and
Bozorgnia (1994), and Sadigh and others (1989) have been incorporated into EQFAULT
(Blake, 1997). For this study, peak horizontal ground accelerations anticipated at the site
were determined based on the random mean plus 1 - sigma attenuation curves developed
by Joyner and Boore (1982), Campbell and Borzorgnia (1994), and Sadigh and others
(1989). These acceleration-attenuation relations have been incorporated in EQFAULT, a
computer program by Thomas F. Blake (1997), which performs deterministic seismic
hazard analyses using up to 150 digitized California faults as earthquake sources.
The program estimates the closest distance between each fault and a user-specified file.
If a fault is found to be within a user-selected radius, the program estimates peak horizontal
ground acceleration that may occur at the site from the "upper bound" (maximum credible)
and "maximum probable" earthquakes on that fault. Site acceleration (g) is computed by
any of the 14 user-selected acceleration-attenuation relations that are contained in
EQFAULT. Based on the above, peak horizontal ground accelerations from an upper
bound event may be on the order of 0.59 g to 0.70 g, and a maximum probable event may
be on the order of 0.38 g to 0.40 g.
Seismic Shaking Parameters
Based on the site conditions, Chapter 16 of the Uniform Building Code (International
Conference of Building Officials, 1997) and Peterson and others (1996), the following
seismic parameters are provided.
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m
to
ta
pi
m
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P*
SAN FRANCISCO
SITE LOCATION (+):
Latitude - 33.1095 N
Longitude - 117.2907 W
Spectrum/Carnation Property
CALFORNIA FAUL
W.O. 2588-A-SC Figure 2
GeoSoils, Inc.
Seismic zone (per Figure 16-2*)
Soil Profile Type (per Table 1 6-J*)
Joyner and Boore Subgrade Type
Seismic Source Type (per Table 16-U*)
Distance to Seismic Source
Upper Bound Earthquake
4
SC.SD**
Class B, C**
B
5 mi. (8 km)
6.9 Mw
* Rgure and table references from Chapter 16 of the Uniform Building Code (1997).
** Dual classifications due to varying earth material types in the upper 100 feet
underlying the site.
GROUNDWATER
Subsurface water was not encountered within the property during field work performed in
preparation of this report. Subsurface water is not anticipated to adversely affect site
development, provided that the recommendations contained in this report are incorporated
into final design and construction. These observations reflect site conditions at the time
of our investigation and do not preclude future changes in local groundwater conditions
from excessive irrigation, precipitation, or that were not obvious, at the time of our
investigation.
Seeps, springs, or other indications of a high groundwater level were not noted on the
subject property during the time of our field investigation. However, seepage may occur
locally (due to heavy precipitation or irrigation) in areas where fill soils overlie silty or clayey
soils. Such soils may be encountered in the earth units that exist onsite.
LABORATORY TESTING
Laboratory tests were performed on a representative sample of representative site earth
materials in order to evaluate their physical characteristics. Test procedures used and
results obtained are presented below.
Classification
Soils were classified visually according to the Unified Soils Classification System. The soil
classifications are shown on the boring logs in Appendix B.
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Laboratory Standard
The maximum density and optimum moisture content was determined for the major soil
type encountered in the borings. The laboratory standard used was ASTM D-1557. The
moisture-density relationship obtained for this soil is shown on the following table:
LOCATION
B-6 @ 0-2"
SOIL TYPE
SILTY SAND, Brownish Orange
(Undocumented Fill)
MAXIMUM DENSITY
(PCF)
123.5
OPTIMUM MOISTURE
CONTENT (%)
12.0
Expansion Index Testing
Expansion index testing was performed on a representative soil sample, according to
Uniform Building Code (UBC) Standard No. 29-2 and outlined in Section 2904(b) of the
UBC. The test result is presented below as well as the expansion classification according
to UBC Table No. 29.c.
LOCATION
B-2 @ 0-2'
B-6 @ 0-2'
SOIL TYPE
SILTY SAND, Reddish Brown and
Orangish Brown
(Topsoil/Lindavista Formation)
SILTY SAND, Brownish Orange
(Undocumented Fill)
EXPANSION INDEX
0
2
EXPANSION POTENTIAL
Very Low
Very Low
Shear Testing
Shear testing was performed on an undisturbed sample in formational materials in general
accordance with ASTM test method D-3080 in a Direct Shear Machine of the strain control
type. The shear test results are presented in the following:
I LOCATION
B-6 @ 0-2'
COHESION (psf)
51 5
INTERNAL FRICTION
29
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Corrosion
A typical sample of the site materials was analyzed for soluble sulfate content and potential
corrosion to ferrous metals. The results are as follows:
LOCATION
B-2 @ 0-2'
B-6@0-2'
SOLUBLE SULFATES
(mg/kg)
17
19
PH
6.9
7.0
RESISTIVITY-SATURATED
(ohms-cm)
1900
1300
Based upon the soluble sulfate test results (UBC range for negligible/low is 0 to 150 ppm
soluble [S04] in water), the site materials have a negligible to low potential for corrosion
to concrete. The results of our pH testing indicates that the site soils are neutral to slightly
acidic. Resistivity test results indicate site soils are highly corrosive to ferrous metals.
Highly corrosive soils are considered to be generally in the range of 1,000 to 2,000 ohms-
cm. The laboratory test results for corrosivity testing are presented in Appendix C.
DISCUSSION AND CONCLUSIONS
General
Based on our field exploration, laboratory testing and geotechnical engineering analysis,
it is our opinion that the subject pad appears suitable for the proposed residential
development from a geotechnical engineering and geologic viewpoint, provided that the
recommendations presented in the following sections are incorporated into the design and
construction phases of site development. The primary geotechnical concerns with respect
to the proposed development are:
• Depth to competent bearing material, including cut/fill transitions.
• Corrosivity of site soils.
• Expansion potential of site soils.
Subsurface water and potential for perched water.
• Regional seismic activity.
The recommendations presented herein consider these as well as other aspects of the site.
In the event that any significant changes are made to proposed site development, the
conclusions and recommendations contained in this report shall not be considered valid
unless the changes are reviewed and the recommendations of this report verified or
modified in writing by this office. Foundation design parameters are considered
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preliminary until the foundation design, layout, and structural loads are provided to this
office for review.
Earth Materials
The existing fill (undocumented) materials encountered on the site range from about 1 to
5 feet in thickness and are generally moist, loose to medium dense, non-homogeneous,
and porous. Based on our observations and laboratory testing, the fill materials appear to
be generally below the current industry minimum standard. Recommendations for the
treatment of existing fills are presented in the earthwork section of this report.
Topsoil/colluvium materials are generally dry, loose, and porous and/or do not meet the
current industry minimum standards. Recommendations for the treatment of colluvium are
presented in the earthwork section of this report.
Formational materials (Lindavista Formation and Santiago Formation) will be encountered
during site earthwork. These materials are considered competent to support settlement-
sensitive structures in their existing state.
Corrosivity
Our laboratory test results indicate that the site materials have a negligible to low sulfate
exposure for corrosion to concrete, are neutral to slightly acidic, and have a high potential
for corrosion to exposed steel.
Expansion Potential
Our laboratory test results indicate that soils with a very low expansion potential underlie
the site. This should be considered during project design. Foundation design and
construction recommendations are provided herein for low expansion potential
classifications.
Subsurface and Surface Water
Subsurface and surface waters, as discussed previously, are not anticipated to affect site
development, provided that the recommendations contained in this report are incorporated
into final design and construction and that prudent surface and subsurface drainage
practices are incorporated into the construction plans. Perched groundwater conditions
along fill/formational contacts and along zones of contrasting permeabilities should not be
precluded from occurring in the future due to site irrigation, poor drainage conditions, or
damaged utilities. Should perched groundwater conditions develop, this office could
assess the affected area(s) ancf provfde the appropriate recommendations to mitigate the
observed groundwater conditions.
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The groundwater conditions observed and opinions generated were those at the time of
our investigation. Conditions may change with the introduction of irrigation, rainfall, or
other factors that were not obvious at the time of our investigation.
Regional Seismic Activity
The seismic acceleration values provided herein should be considered during the design
of the proposed development.
EARTHWORK CONSTRUCTION RECOMMENDATIONS
General
All grading should conform to the guidelines presented in Appendix Chapter A33 of the
Uniform Building Code (adopted and current edition), the requirements of the County of
San Diego, and the Grading Guidelines presented in this report as Appendix D, except
where specifically superseded in the text of this report. Prior to grading GSI's
representative should be present at the preconstruction meeting to provide additional
grading guidelines, if needed, and review the earthwork schedule. Earthwork beyond the
limits of the surficial, remedial overexcavations or those indicated on the grading plan
should be reviewed by the geologist and/or geotechnical consultant prior to and following
these additional removals.
During earthwork construction all site preparation and the general grading procedures of
the contractor should be observed and the fill selectively tested by a representative(s) of
GSI. If unusual or unexpected conditions are exposed in the field or if modifications are
proposed to the rough grade or precise grading plan, they should be reviewed by this
office and if warranted, modified and/or additional recommendations will be offered. All
applicable requirements of local and national construction and general industry safety
orders, the Occupational Safety and Health Act, and the Construction Safety Act should
be met. Excavations into the granular material on this site may be unstable.
Site Preparation
Debris, vegetation, and other deleterious material (including remnants of the previously
existing structures) should be removed from the improvement(s) area prior to the start of
construction.
Removals (Unsuitable Surficial Materials!
Due to the desiccated and relatively loose condition of the undocumented fill and
topsoil/colluvium on the site, removals should consist of all undocumented fill soils and
topsoil/colluvial materials to bedrock within settlement-sensitive improvements and to a 1:1
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horizontal to vertical projection from the bottom outside edge of the settlement-sensitive
improvements, and within parking/driveway areas.
Once these materials are removed, the bottom of the excavations should be observed and
tested by a representative of GSI. The bottom areas approved to receive fill should be
scarified in two perpendicular directions and moisture conditioned (at or above the soils
optimum moisture content) to a depth of 12 inches and compacted to a minimum 90
percent relative compaction. At that time, the removed existing earth materials may be re-
used as fill, provided the materials are moisture conditioned at or above the soils optimum
moisture and compacted in accordance with the recommendations of this report.
Overexcavation
Bedrock materials occur at, or near, existing grade within the portions of the parcel. It is
likely that a cut/fill transition condition will be created during grading to provide design
elevations for proposed development. In order to provide for uniform structural support,
areas underlain by bedrock materials at the surface and within 3 feet of proposed grade,
should be overexcavated to provide a minimum 3-foot layer of compacted fill and at least
5 feet outside the limits of the outer-most foundation elements. The limits of any bedrock
overexcavation should be determined once a grading plan for the site is made available.
This 3-foot overexcavation is considered a minimum and within the limits of the building
assumes a maximum 2-foot footing embedment (from lowest adjacent soil grade). If
embedments are greater than 2 feet, the overexcavation should be increased to a
minimum of 3 feet beyond the bottom of the footing and 6 feet laterally beyond the width
of the footing.
Following overexcavation, the bottom areas approved to receive fill should first be scarified
in two perpendicular directions and moisture conditioned (at or above the soils optimum
moisture content) to a depth of 12 inches and compacted to a minimum 90 percent relative
compaction.
Fill Placement
1. Fill materials should be brought to at least optimum moisture, placed in thin 6- to
8- inch lifts and mechanically compacted to obtain a minimum relative compaction
of 90 percent of the laboratory standard.
2. Fill materials should be cleansed of major vegetation and debris prior to placement.
3. Any oversized rock materials greater than 12 inches in diameter should not be
placed within the upper 3 feet of the proposed foundation, and the upper 12 inches
of finish grade materials on pads should consist of 6 inch and minus earth materials.
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4. Any import materials should be observed and determined suitable by the soils
engineer prior to placement on the site. Foundation designs may be altered if
import materials have a greater expansion value than the onsite materials
encountered in this investigation.
Slope Considerations and Slope Design
It is our understanding that construction of slopes is not proposed on the site. Therefore,
evaluation of slope stability is not included in this report. However, should slopes be
planned, all slopes should be designed and constructed in accordance with the minimum
requirements of County of San Diego and the recommendations in Appendix D.
RECOMMENDATIONS- FOUNDATIONS
Preliminary Foundation Design
1. The foundation systems should be designed and constructed in accordance with
guidelines presented in the latest edition of the UBC.
2. An allowable bearing value of 1,500 pounds per square foot may be used for design
of footings that maintain a minimum width of 12 inches and a minimum depth of 12
inches. This value may be increased by 200 pounds per square foot for each
additional 12 inches in depth to a maximum value of 2,500 pounds per square foot.
In addition, this value may be increased by one-third when considering short
duration seismic or wind loads. Continuous footings should be at least 15 inches
wide, and isolated pad footings should have a minimum dimension of at least 24
inches square.
3. Passive earth pressure may be computed as an equivalent fluid having a density of
250 pounds per cubic foot, with a maximum earth pressure of 2,500 pounds per
square foot.
4. An allowable coefficient of friction between soil and concrete of 0.40 may be used
with the dead load forces.
5. When combining passive pressure and frictional resistance, the passive pressure
component should be reduced by one-third.
6. Soil generated from footing excavations to be used onsite should be moisture
conditioned to at least optimum moisture content and compacted to at least 90
percent minimum relative compaction, whether it is to be placed inside the
foundation perimeter, or in the parking areas. This material must not alter positive
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drainage patterns that direct drainage away from the structural area and toward the
street.
7. Expansion/construction joints for differential movement between proposed and
existing structures should be provided by the structural engineer/architect.
Foundation Construction
The following foundation construction recommendations are presented as minimum criteria
from a soils engineering viewpoint. Our recommendations are presented assuming that
the upper 3 feet of finish grade materials have a very low to low expansion potential.
Recommendations by the project structural engineer or architect, which may exceed the
soils engineer's recommendations, should take precedence over the following minimum
recommendations. Final foundation design recommendations will be provided based on
the expansion potential of the as-graded foundation soils.
1. Exterior and interior footings should be founded at a minimum depth of 12 inches
for one-story floor loads, and 18 inches below the lowest adjacent ground surface
for two-story floor loads. All footings should be reinforced with two No. 4 reinforcing
bars, one placed near the top and one placed near the bottom of the footing.
Footing widths should be as indicated in the Uniform Building Code (International
Conference of Building Officials, 1997).
2. A grade beam, reinforced as above, and at least 12 inches wide should be provided
across large (e.g. doorways) entrances. The base of the grade beam should be at
the same elevation as the bottom of adjoining footings.
3. Concrete slabs, where moisture condensation is undesirable, should be underlain
with a vapor barrier consisting of a minimum of 6 mil polyvinyl chloride or equivalent
membrane with all laps sealed. This membrane should be covered with a minimum
of 2 inches of sand to aid in uniform curing of the concrete and to protect the
membrane from puncture.
4. Concrete slabs should be a minimum of 4 inches thick, and should be reinforced
with 6 inch by 6 inch, No. 10 by No. 10 (6x6 - W1.4 x W1.4) welded-wire mesh or
No. 3 reinforcing bar at 24 inches on center. If welded wire mesh is selected, No.
3 reinforcing bar at 24 inches on center should be doweled between the exterior
footing and 3 feet into the slab. All slab reinforcement should be supported to
ensure placement near the vertical midpoint of the concrete. "Hooking" the wire
mesh is not considered an acceptable method of positioning the reinforcement.
5. Garages are not anticipated, but if constructed, slabs should be reinforced as above
and poured separately from the structural footings and quartered with expansion
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joints or saw cuts. A positive separation from the footings should be maintained
with expansion joint material to permit relative movement.
6. Presaturation is not required for these soil conditions. The moisture content of the
subgrade soils should be equal to or greater than optimum moisture content in the
slab areas. Prior to placing visqueen or reinforcement, soil moisture content should
be verified by this office within 72 hours of pouring slabs.
FOOTING SETBACKS
All footings should maintain a minimum 7-foot horizontal setback from the base of the
footing to any descending slope. This distance is measures from the footing face at the
bearing elevation. Footings should maintain a minimum horizontal setback of H/3
(H=slope height) from the base of the footing to the descending slope face and no less
than 7 feet nor need to be greater than 40 feet. Footings adjacent to unlined drainage
swales should be deepened to a minimum of 6 inches below the invert of the adjacent
unlined swale. Footings for structures adjacent to retaining walls should be deepened so
as to extend below a 1:1 projection from the heel of the wall. Alternatively, walls may be
designed to accommodate structural loads from buildings or appurtenances as described
in the retaining wall section of this report.
CORROSION AND CONCRETE MIX
Laboratory test results indicate that the site materials have a low to negligible potential for
sulfate attack and corrosion to concrete. Therefore, sulfate-resistant Type V concrete is
not required; and Type II concrete may be utilized. The design criteria presented in Table
19-A-2 and 19-A-3 of the UBC (1994 edition) should be followed. Upon completion of
grading, additional testing of soils (including import materials) should be considered prior
to the construction of utilities and foundations. Inasmuch as the test results indicate that
the site soils have a high potential for corrosion to ferrous metals, utilities should be
wrapped with a protective coating. Alternative methods and additional comments may be
obtained from a qualified corrosion engineer.
RETAINING WALL RECOMMENDATIONS
General
The equivalent fluid pressure parameters provide for either the use of very low expansive
granular backfill to be utfffzecf behind" the proposed1 waifs. The very tow expansive granular
backfill should be provided behind the wall at a 1:1 (h:v) projection from the heel of the
foundation system. Low expansive fill is Class 3 aggregate baserock or Class 2 permeable
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rock. Wall backfilling should be performed with relatively light equipment within the same
1:1 projection (i.e., hand tampers, walk behind compactors). Highly expansive soils should
not be used to backfill any proposed walls. During construction, materials should not be
stockpiled behind nor in front of walls for a distance of 2H where H is the height of the wall.
Retaining walls should be designed to be seismically resistant, in accordance with the
latest edition of the Uniform Building Code.
Foundation systems for any proposed retaining walls should be designed in accordance
with the recommendations presented in the Foundation Design section of this report.
Building walls, below grade, should be water-proofed or damp-proofed, depending on the
degree of moisture protection desired. All walls should be properly designed in
accordance with the recommendations presented below.
Some movement of the walls constructed should be anticipated as soil strength
parameters are mobilized. This movement could cause some cracking depending upon
the materials used to construct the wall. To reduce the potential for wall cracking, walls
should be internally grouted and reinforced with steel. To mitigate this effect, the use of
vertical crack control joints and expansion joints, spaced at 20 feet or less along the walls
should be employed. Vertical expansion control joints should be infilled with a flexible
grout. Wall footings should be keyed or doweled across vertical expansion joints.
Restrained Walls
Any retaining walls that will be restrained prior to placing and compacting backfill material
or that have re-entrant or male corners, should be designed for an at-rest equivalent fluid
pressures (EFP) of 65 pcf, plus any applicable surcharge loading. This restrained-wall,
earth pressure value is for select backfill material only. For areas of male or re-entrant
corners, the restrained wall design should extend a minimum distance of twice the height
of the wall laterally from the corner.
Building walls below grade or greater than 2 feet in height should be water-proofed or
damp-proofed, depending on the degree of moisture protection desired. The wall should
be drained as indicated in the following section. For structural footing loads within the 1:1
zone of influence behind wall backfill, refer to the following section.
Cantilevered Walls
These recommendations are for cantilevered retaining walls up to 10 feet high. Active
earth pressure may be used for retaining wall design, provided the top of the wall is not
restrained from minor deflections. An empirical equivalent fluid pressure approach may
be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights
are provfded for specific sfope gradfents of the retained matenar. These do not fnclude
other superimposed loading conditions such as traffic, structures, seismic events,
expansive soils, or adverse geologic conditions.
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SURFACE SLOPE OF RETAINED
MATERIAL (horizontal to vertical)
Level**
2to1
EQUIVALENT FLUID WEIGHT FOR
SELECT VERY LOW
EXPANSIVE SOIL*
30
43
*To be increased by traffic, structural surcharge and seismic loading as needed.
**Level walls are those where grades behind the wall are level for a distance of 2H.
Wall Backfill and Drainage
All retaining walls should be provided with an adequate backdrain and outlet system
(a minimum two outlets per wall and no greater than 100 feet apart), to prevent buildup of
hydrostatic pressures and be designed in accordance with minimum standards presented
herein. See site wall drain options (Figure 3, Figure 4, and Figure 5). Drain pipe should
consist of 4-inch diameter perforated schedule 40 PVC pipe embedded in gravel. Gravel
used in the backdrain systems should be a minimum of 3 cubic feet per lineal foot of %-
to 1-inch clean crushed rock wrapped in filter fabric (Mirafi 140 or equivalent) and 12
inches thick behind the wall. Where the void to be fitted is constrained by lot lines or
property boundaries, the use of panel drains (Mirafi 5000 or equivalent) may be considered
with the approval of the project geotechnical engineer. The surface of the backfill should
be sealed by pavement or the top 18 inches compacted to 90 percent relative compaction
with native soil. Proper surface drainage should also be provided. Weeping of the walls
in lieu of a backdrain is not recommended for walls g'reater than 2 feet in height. For walls
2 feet or less in height, weepholes should be no greater than 6 feet on center in the bottom
coarse of block and above the landscape zone.
A paved drainage channel (v-ditch or substitute), either concrete or asphaltic concrete,
behind the top of the walls with sloping backfill should be considered to reduce the
potential for surface water penetration. For level backfill, the grade should be sloped such
that drainage is toward a suitable outlet at 1 to 2 percent.
Retaining Wall Footing Transitions
Site walls are anticipated to be founded on footings designed in accordance with the
recommendations in this report. Wall footings may transition from bedrock to gravelly fill
to select fill. If this condition is present the civil designer may specify either:
a) If transitions from rock fill to select fill transect the wall footing alignment at an angle
of less than 45 degrees (plan view), then the designer should perform a minimum
2-foot overexcavation for a distance of two times the height of the wall and increase
overexcavation until such transition is between 45 and 90 degrees to the wall
alignment.
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W.O. 2588-A-SC
Decembers, 1998
Page 17
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Waterproofing
Manufactured drainage
Geacomposite drain
( Mira drain 5000 or
equivalent )
Note: Filter fabric wraps completely
around perforated pipe and
behind core material, core
material wrcps beneath
bottom of pipe.
4" die. min. perforated
pipe placed with holes
down and sloped at 1 —2%
to suitable outlet
4" min. granular materiel
(class 2 permeable or
3/8 — 1" clean crushed
rock wrapped in a
filter fabric)
,— Ceo drcin (cut off)
I IS" below soil line
Site retcinina wci!
(structural design
by others)
Pavement section per —;GSI recommendations j
ijveiirsiiwfc i«f"^ «!i x> -^ r e). * A. ~* "V^^
Wall footing
(designed by others)
SCHEMATIC OF SITE WALL DRAIN
^_^ OPTION A Figure
DATE 12/98 W.O. NO.2588-A-SC
Geotechnical • Geologic • Environmental
FORM 89/22
12" thick (min.) drain rock
(class 2 permecble) or
other acceptable granular
material, 1/8-1" clean
crushed rock wrapped in
a filter fabric (Mi'rafi 140
or equivalent)
4" dia. min. perforated
pipe placed with holes
down and sloped at 1 —2%
to a suitable outlet
I—Cap drain (cut off)
i 15" below sail line
Site retaining well
(structural design
by others)
Pavement section per
GSI recomendations —
Finished lot surface
_L
4"
«
—I
4" Min.
f -
o .
» I I o
:».-.',- •.. .to' I o .r , . I o « ••
——4" Min. ' ' ° ' »...«-.• • A • *
•* I o° f ' •
-Wall footing
<designed by others)
SCHEMATIC OF SITE WALL DRAIN
OPTION B
DATE 12/98
Figure 4
W.O. NOL 2588-A-SC
Geotechnicai • Geologic • Environmental
FORM 89/22
If finished surface is within
8" of top of footing well drcins
shell be at 6' intervals along
the length of the wall and
located'at the level of the
bottom course of block. The
drcins shell be 4" in diameter
Cac drain ' (cut off)
18" beiow scii line
•Site retaining wail
(structural design
by others)
24-1' thick (min.) drain rock
(class 2 permeable) or
other acceptable granular
materiel, 1/8—1" clean
crushed rock wrcoped in
c filter fabric (Mirer" 140
or equivalent)
Waterproofing
Pcvemenc section pe
GSi recomencctions
^^ .'
•..-. •.'.*. V,V'•»>•?•'•:'••,•. v, •••:••••:"•,',-•.•.'••'/.• :\',-.<*•: '•>'••• •<:•->1 ,. I o » • f ,^ j.1. .«•».. ' A • * ' •' .i • rf .« • ' i •• i « *•.'
-Vail footing'-'—' ' toy others)
SCHEMATIC OF SITE WALL DRAIN
OPTION C Figure5
DATE 12/98 W.O. NO.2588-A-SC
Geotechnical • Geologic • Environmental
FORM 89/22
b) Increase of the amount of reinforcing steel and wall detailing (i.e., expansion joints
or crack control joints) such that an angular distortion of 1/360 for a distance of 2H
(where H=wall height in feet) on either side of the transition may be
accommodated. Expansion joints should be sealed with a flexible, non-shrink
grout.
c) Embed the footings entirely into a homogeneous compacted fill.
FLATWORK AND ASSOCIATED IMPROVEMENTS
1. Planters and walls should not be tied to building(s).
2. Driveways, sidewalks, and patios adjacent to the building(s) should be separated
from the building(s) with thick expansion joint filler material. In addition, all
sidewalks and driveways should be quartered and poured with expansion joints no
farther apart than 8 feet for 4-inch slabs or 10 feet for 5-inch slabs, respectively. To
improve the performance of the driveway and/or sidewalks constructed on the
native soils, consideration should be given to pre-moistening of the soils prior to
placement of driveways and sidewalks to 120 percent of optimum moisture.
Consideration should additionally be given for the areas of the driveways and
sidewalks adjacent to planters, lawns, and other landscape areas to have thickened
edges, such that the edge is 4 to 6 inches thick and at least 6 inches below the
adjacent landscaping zone (section).
3. Overhang structures should be structurally designed with continuous footings or
grade beams tied in at least two directions. Footings that support overhang
structures should be embedded a minimum of 24 inches from the lowest adjacent
finished subgrade.
4. Any masonry landscape walls that are to be constructed throughout the property
should be fully grouted and articulated in segments no more than 20 feet long.
5. Utilities should be enclosed within a closed vault or designed with flexible
connections to accommodate differential settlement and expansive soil conditions.
6. Finish grade (Precise Grade Plan) on the lot should provide a minimum of 1 to 2
percent fall to the street. It should be kept in mind that drainage reversals could
occur if relatively flat yard drainage gradients are not maintained due to landscaping
work, modifications to flatwork, or post-sale homeowner modifications.
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Tile Flooring
Tile flooring can crack, reflecting cracks in the concrete slab below the tile. Therefore, the
designer should consider additional steel reinforcement of concrete slabs on-grade where
tile will be placed. The tile installer should consider installation methods that reduce
possible cracking of the tile such as slipsheets. Slipsheets or a vinyl crack isolation
membrane (approved by the Tile Council of America/Ceramic Tile Institute) is
recommended between tile and concrete stabs on grade.
Gutters and Downspouts
Consideration should be given to the installation of gutters and downspouts to collect roof
water that may otherwise infiltrate the soils adjacent to the structures. The downspouts
should be drained away from the foundation and collected in drainage swales or other
approved non-erosive drainage systems designed by a registered civil engineer
(specializing in drainage) to convey water away from the foundation. Gutters and
downspouts are not a geotechnical requirement, however, provided positive drainage is
maintained in accordance with the recommendations of the design civil engineer.
Exterior Slabs and Walkways
Exterior concrete slabs-on-grade (walkways, patios, etc.) should be constructed with a
minimum 4-inch thick slab, and reinforced with steel rebar or welded mesh. The
reinforcement should consist of 6x6 - W1.4 x W1.4 welded-wire mesh or equivalent. It is
important for the performance of the slab that the reinforcing be located near mid-slab
thickness using chairs, supports, etc. Hooking is not an acceptable method of
reinforcement placement, and is not recommended.
Distortions on the exterior slab-on-grade due to potentially expansive soils and proximity
to slopes may warrant additional mitigation. This may include crack control joints (4 to 6
feet spacing in horizontally perpendicular directions [long axis and short axis]), and
expansion control joints at intervals 10 feet or less. Other considerations for mitigation may
include the use of thickened edges (see above) for slabs at the top of slopes, fiber mesh
mixed into the concrete, or pre-saturation of subgrade soils to 120 percent of optimum
moisture content, to a depth of 18 inches.
Air conditioning (A/C) units should be supported by slabs that are incorporated into the
building foundation or constructed on a rigid slab with flexible couplings for plumbing and
electrical lines. A/C waste water lines should be drained to a suitable outlet (see previous
section).
Shrinkage cracks in concrete could become excessive if proper finishing and curing
practices are not followed. Finishing and curing practices should be performed per the
Portland Cement Association Guidelines. Mix design should incorporate rate of curing for
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GeoSoils, Inc.
climate and time of year, sulfate content of soils, corrosion potential of soils, and fertilizers
used on site.
ADDITIONAL RECOMMENDATIONS/DEVELOPMENT CRITERIA
Additional Site Improvements
If in the future, any additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said
improvements could be provided upon request this includes but not limited to appurtenant
structures.
This office should be notified in advance of any additional fill placement, regrading of the
site, or trench backfilling after rough grading has been completed. This includes any
grading, utility trench, and retaining wall backfills.
Erosion and Sedimentation Control
The objective of the National Pollutant Discharge Elimination System (NPDES)
requirements are to reduce (or eliminate) discharge of non-stormwater runoff from
construction sites. One of the best management practices (BMP's) to mitigate significant
erosion from sites in the grading phase of construction is implementation of structural
containment devices, including but not limited to sandbags, retention basins, hay bales,
etc. BMP's should be developed prior to the start of mass grading. As described in the
General Permit, a Storm Water Pollution Prevention Plan (SWPPP) specific to the subject
development is required, and should include an erosion control plan presenting best
management practices (BMP's) for runoff control. The erosion control plan should be
exhibited on the grading plans. The SWPPP should be maintained until a post-
construction management plan is in effect. These services would be provided by GSI
upon request.
Landscape Maintenance and Planting
Water has been shown to weaken the inherent strength of soil, and slope stability is
significantly reduced by overly wet conditions. Positive surface drainage away from graded
slopes should be maintained and only the amount of irrigation necessary to sustain plant
life should be provided for planted slopes. Over-watering should be avoided. Onsite soil
materials should be maintained in a solid to semisolid state.
Brushed native and graded slopes (constructed within and utilizing onsite materials) would
be potentially erosive. Eroded debris may be minimized and surficial slope stability
enhanced by establishing and maintaining a suitable vegetation cover soon after
construction. Plants selected for landscaping should be light weight, deep rooted types
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that require little water and are capable of surviving the prevailing climate. Planting of large
trees with potential for extensive root development should not be placed closer than 10
feet from the perimeter of the foundation or the anticipated height of the mature tree,
whichever is greater. In order to minimize erosion on the slope face, an erosion control
fabric (i.e. jute matting) should be considered.
From a geotechnical standpoint, leaching is not recommended for establishing
landscaping. If the surface soils area processed for the purpose of adding amendments
they should be recompacted to 90 percent minimum relative compaction. Moisture
sensors, embedded into fill slopes, should be considered to reduce the potential of
over-watering from automatic landscape watering systems. The use of certain fertilizers
may affect the corrosion characteristics of soil. Review of the type and amount
(pounds per acre) of the fertilizers by a corrosion specialist should be considered.
If in the future, any additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said
improvements could be provided upon request. This office should be notified in advance
of any fill placement, regrading of the site, or trench backfilling after rough grading has
been completed. This includes any grading, utility trench, and retaining wall backfills.
Drainage
Positive site drainage should be maintained at all times. Drainage should not flow
uncontrolled down any descending slope. Water should be directed away from
foundations and not allowed to pond and/or seep into the ground. Pad drainage should
be directed toward the street or other approved area. Landscaping should be graded to
drain into the street, or other approved area. All surface water should be appropriately
directed to areas designed for site drainage.
Roof gutters and down spouts are recommended to control roof drainage. Down spouts
should outlet a minimum of 5 feet from proposed structures or tightlined into a subsurface
drainage system. We recommend that any proposed open bottom planters adjacent to
proposed structures be eliminated for a minimum distance of 10 feet. As an alternative,
closed bottom type planters could be utilized. An outlet placed in the bottom of the
planter, could be installed to direct drainage away from structures or any exterior concrete
flatwork. Drainage behind top of walls should be accomplished along the length of the wall
with a paved channel drainage v-ditch or substitute.
Footing Trench Excavation
All footing trench excavations should be observed and approved by a representative of this
office prior to placing reinforcement. Footing trench spoil and any excess soils generated
from utility trench excavations should be compacted to a minimum relative compaction of
90 percent, if not removed from the site.
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Trench Backfill
All excavations should be observed by one of our representatives and conform to OSHA
and local safety codes. Exterior trenches should not be excavated below a 1:1 projection
from the bottom of any adjacent foundation system. If excavated, these trenches may
undermine support for the foundation system potentially creating adverse conditions.
1. All utility trench backfill in slopes, structural areas and beneath hardscape features
should be brought to near optimum moisture content and then compacted to obtain
a minimum relative compaction of 90 percent of the laboratory standard.
Observations, probing and, if deemed necessary, testing should be performed by
a representative of this office to verify compactive efforts of the contractor.
2. Soils generated from utility trench excavations should be compacted to a minimum
of 90 percent (ASTM D-1557) if not removed from the site.
3. Jetting of backfill is not recommended.
4. The use of pipe jacking to place utilities is not recommended on this site due to the
presence of gravels and cobbles.
5. Bottoms of utility trenches should be sloped away from structures.
TRENCH BACKFILL
1. All utility trench backfill in structural areas, slopes, and beneath hardscape features
should be brought to at least optimum moisture content and then compacted to
obtain a minimum relative compaction of 90 percent of the laboratory standard.
Flooding/jetting is not recommended for the site soil materials. As an alternative,
SE 30 or greater sand, may be flooded/jetted in shallow under-slab interior
trenches.
2. Select sand backfill should not be allowed in exterior trenches adjacent to and
within an area extending below a 1:1 plane projected from the outside bottom edge
of the footing.
3. All trench excavations should conform to CAL-OSHA and local safety codes.
PLAN REVIEW
Final site development and foundation plans should be submitted to this office for review
and comment, as the plans become available, for the purpose of minimizing any
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misunderstandings between the plans and recommendations presented herein. In
addition, foundation excavations and any additional earthwork construction performed on
the site should be observed and tested by this office. If conditions are found to differ
substantially from those stated, appropriate recommendations would be offered at that
time.
INVESTIGATION LIMITATIONS
The materials encountered on the project site and utilized in our laboratory study are
believed representative of the area; however, soil and bedrock materials vary in character
between excavations and natural outcrops or conditions exposed during site grading,
construction, and our post-grading study. Site conditions may vary due to seasonal
changes or other factors. GSI assumes no responsibility or liability for work, testing, or
recommendations performed or provided by others.
Inasmuch as our study is based upon the site materials observed, selective laboratory
testing and engineering analysis, the conclusion and recommendations are professional
opinions. These opinions have been derived in accordance with current standards of
practice and no warranty is expressed or implied. Standards of practice are subject to
change with time. GSI performed this study within the constraints of a budget
During the field exploration phase of our study, odors or stained or discolored soils were
not observed onsite or in our excavation spoils. However, these observations were made
during our preliminary geotechnical study and should in no way be used in lieu of an
environmental assessment. If requested, a proposal for a phase I preliminary
environmental assessment could be provided.
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" REFERENCES
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APPENDIX A
REFERENCES
Blake, Thomas F., 1997, EQFAULT computer program and users manual for deterministic
prediction of horizontal accelerations from digitized California faults.
Campbell, K.W., 1993, Empirical prediction of near-source ground motion from large
earthquakes, in Johnson, J.A., Campbell, K.W., and Blake, eds., T.F., AEG Short
Course, Seismic Hazard Analysis, June 18,1994.
Greensfelder, R. W., 1974, Maximum credible rock acceleration from earthquakes in
California: California Division of Mines and Geology, Map Sheet 23.
Hart, E.W., 1994, Fault-rupture hazard zones in California: California Department of
Conservation, Division of Mines and Geology, Special Publication 42.
Housner, G. W., 1970, Strong ground motion jn Earthquake Engineering, Robert Wiegel,
ed., Prentice-Hall.
International Conference of Building Officials, 1997, Uniform building code: Whittier,
California.
Jennings, C.W., 1994, Fault activity map of California and adjacent areas: California
Division of Mines and Geology, Map Sheet No. 6, scale 1:750,000.
Joyner, W.B, and Boore, D.M., 1982a, Estimation of response-spectral values as functions
of magnitude, distance and site conditions, jn Johnson, J.A., Campbell, K.W., and
Blake, eds., T.F., AEG Short Course, Seismic Hazard Analysis, June 18,1994.
, 1982b, Prediction of earthquake response spectra, jn Johnson, J.A., Campbell,
K.W., and Blake, eds., T.F., AEG Short Course, Seismic Hazard Analysis, June 18,
1994.
Sadigh, K., Egan, J., and Youngs, R., 1987, Predictive ground motion equations reported
in Joyner, W.B., and Boore, D.M., 1988, "Measurement, characterization, and
prediction of strong ground motion", in Earthquake Engineering and Soil Dynamics
II, Recent Advances in Ground Motion Evaluation, Von Thun, J.L., ed.: American
Society of Civil Engineers Geotechnical Special Publication No. 20, pp. 43-102.
Sowers and Sowers, 1970, Unified soil classification system (After U. S. Waterways
Experiment Station and ASTM 02487-667) jn Introductory Soil Mechanics, New
York.
San Diego County, 1970, Aerial photographs, Flight Line 3, photograph nos. 3 and 4, April
14.
GeoSoils, Inc.
Wilson, Kenneth Lee, 1972, Eocene and related geology of a portion of the San Luis Rey
and Encinitas quadrangles, San Diego County, California: unpublished masters
thesis, University of California Riverside, December.
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APPENDIX B
• BORING LOGS
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BORING LOG
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
Depth (f t . )-
5-
10-
15-
20-
25-
Sample
*:
3
CO Und i s-turbed4-
4-
\
111
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BORING B-1 SHEET 1 OF 1
DATE EXCAVATED 1 1 -1 6-98
SAMPLE METHOD: Hand Auger
1 Standard Penetration Test
, % Water Seepage into holej Undisturbed, Ring Sample
Description of Material
,^> .LINDAVISTA FORMATION
@ 0', SILTY SANDSTONE, yellowish orange, dry to damp,
\ medium dense to dense; some iron oxide nodules. r
\@ 1 1/2', refusal. /
Total Depth = 1 1/2'.
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. pMrf „.,
BORING LOG
GeoSoils, Inc.
W.O. 2588-A-SC
PROJECT: SPECTRUM COMMUNITIES BORING B-2 SHEET 1 OF 1
DATE EXCAVATED 11-16-98
4-
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fty Water Seepage into hole
K>:>; Undisturbed, Ring Sample
Description of Material
^•
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TOPSOIL
T @ 0', SILTY SAND, brown to reddish brown, dry, loose; /-
\porous. /
LINDAVISTA FORMATION r
l@ 1', SILTY SANDSTONE, orange brown, dry to damp,
(medium dense. I
@ 2', as per 1', damp to moist.
@ 2 1/2', refusal j
Total Depth = 21/2'.
No groundwater encountered
Backfilled 11-16-98
-
GeoSoils, Inc. pM7£ B2
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
a
01
5-
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BORING B-3 SWf£7 1 OF 1
OX1 Tf FXCXl VA TED 11-1 6-98
SAMPLE METHOD: Hand Auger
1
m
j Standard Penetration Test
-. % Water Seepage into hole] Undisturbed, Ring Sample
Description of Material
--
^
ARTIFICIAL FILL - UNDOCUMENTED
\dense; porous. /
I LINDAVISTA FORMATION I
@ 1', SILTY SANDSTONE, yellowish orange, very moist,
\medium dense. /
Total Depth = 2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc.PLA TE «•"
BORING LOG
GeoSoils, Inc.
W.O. 2588-A-SC
PROJECT: SPECTRUM COMMUNITIES BORING B-4 SHEET 1 OF 1
DA TE EXCA VATED 11-1 6-98
+
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Description of Material
•<*•. •
- — .
ARTIFICIAL FILL - UNDCUMENTED
@ 0', SILTY SAND, dark brown, moist, medium dense;
porous. r
@ 3/4', SILTY SAND, brownish orange, moist, medium
dense; moderate pebbles, very hard to dig after 3/4' due to 1
gravels. f
Total Depth = 1 1/2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. PLAJE B.4
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
Depth (f t. )-
5-
10-
15-
20-
25-
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^
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W.O. 2588-A-SC
BORING B-5 SHEET 1 OF 1
DA TE EXCA VA TED 11-16-98
SAMPLE METHOD: Hand Auger
1
H
] Standard Penetration Test
%j Water Seepage into hole
1 Undisturbed, Ring Sample
Description of Material
- i rnp?:nii
^s~\@ 0', SILTY SAND, dark brown, dry, loose; porous. /
^LINDAVISTA FORMATION @ 1/2', SILTY SANDSTONE, f
\brownish orange, dry to damp, medium dense to dense. /
Total Depth = 1 1/2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. pMr£ B5
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
+•4-
.C•1-
Q.
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1
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W.O. 2588-A-SC
BORING B-6 SHEET 1 OF 1
DA TE EXCA VATED 11-1 6-98
SAMPLE METHOD: Hand Auger
1
^L
Standard Penetration Test
<ty Water Seepage into holeUndisturbed, Ring Sample
Description of Material
. -~r*. '
•~>~
\
ARTIFICIAL FILL - UNDOCUMENTED
@ 0', SILTY SAND, brownish orange to black to blue green,
very moist, medium dense; porous, some pebbles, rootlets,
organics, mottled material.
~\@ 2 1/2', refusal on rock or debris [
Total Depth = 21/2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. pLAJ£ M
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
i
t-
x:
ID
5-
10-
15-
20-
25-
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i|
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W.O. 2588-A-SC
BORING B-7 SHEET 1 OF 1
DATE EXCAVATED 1 1-1 6-98
SAMPLE METHOD: Hand Auger
H
Standard Penetration Test
^ Water Seepage into holeUndisturbed, Ring Sample
Description of Material
i:
ARTIFICIAL FILL - UNDOCUMENTED
@ 0', SILTY SAND, reddish brown to brownish orange, moist
to wet, medium dense; porous, mottled material.
^@ 2 1/2', refusal on Lindavista Formation /"
Total Depth = 21/2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. B7
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
+-t-
.c+•a.aa
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W.O. 2588-A-SC
BORING B-8 SHEET 1 OF 1
DATE EXCAVATED 11-16-98
SAMPLE METHOD: Hand Auger
1
m
I Standard Penetration Test
, £y Water Seepage into holeUndisturbed, Ring Sample
Description of Material
^~.
ARTIFICIAL FILL - UNDOCUMENTED
@ 0', SILTY SAND, dark brown to dark orange brown, damp,
T medium dense; porous. r
\@ 1/2', as per 0', moist. /
\@ 1 1/2', refusal on Lindavista Formation /
Total Depth = 1 1/2'.
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. pMr£ M
GeoSoils, Inc.
PROJECT: SPECTRUM COMMUNITIES
•i-q-
£.+•
Q.o)a
-
-
5-
10-
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25-
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*:
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W.O. 2588-A-SC
BORING B-9 SHEET 1 OF 1
DATE EXCAVATED 11-16-98
SAMPLE METHOD: Hand Auger
1
I
I Standard Penetration Test
, ^ Water Seepage into hole
Undisturbed, Ring Sample
Description of Material
^
ARTIFICIAL FILL - UNDOCUMENTED
@ 0', SILTY SAND, dark brown to dark orange brown, dry to
damp, loose to medium dense; porous.
1@ 1/2', as per 0', moist. f
l@ 1', SILTY SAND, brownish orange, wet, medium dense. I
\@ 2', refusal on Lindavista Formation /
Total Depth = 2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. pLAJE B.g
BORING LOG
GeoSoils, Inc.
W.O. 2588-A-SC
PROJECT: SPECTRUM COMMUNITIES BORING B-10 SHEET 1 OF 1
DATE EXCAVATED 1 1 -1 6-98
+•
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, — _. % Wafer Seepage into holeP / 1 Undisturbed, Ring Sample
Description of Material
~~
^-.'
-^
v^-
ARTIFICIAL FILL - UNDOCUMENTED
@ 0', SILTY SAND, brown, dry to damp, loose; porous.
@ 1/2', as per 0', moist.
@ 1', SILTY SAND, tan to light yellowish brown, moist,
1 medium dense; porous. T
@ 2', SITLY SANDSTONE, grayish brown, moist, dense.
\@ 2 1/2', refusal /
Total Depth = 21/2'
No groundwater encountered
Backfilled 11-16-98
GeoSoils, Inc. Tr. _ ._PLA TE &~ ' ^
c
c
c
• APPENDJXC
C LABORATORY TEST RESULTS
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SJUSUSHSJ tC8
BABCOCK
SONS, INC.
Environmental Uaboralory Certification *1156
8100 Quail Valtey Court Riverside, CA 92507-0704
P.O. Box 432 Riverside. CA 92502-0433
PH (909) 653-3351 FAX (909) 653-1662
e-mail: e6bsaJaseaol.com
www.babcodclabs-com
2277
Client:GeoSoils, Inc.
5741 Palmer Way
Carlsbad,CA 92008
Client Z.D.:
Site:
Description:
Matrix:
Constituent
Saturated Paste pH
Redox Potential
Saturated Resistivity
TP-200-2.2
WO#2588-A-8C
soil-ag
Result
Date Reported: 12/02/98
Collected By:
Date: 11/19/98
Time: 0000
Submitted By: Courier
Date: 11/20/98
Time: 0845
Xathod BL
unite S-1.10 W.Statesw*"^^awmV SM 2580
none »2
ohm-cm SM 252QB
0.1& V *1
•*,
o
Sate /
Aaalyat
981201/BW
981201/BW
981201/BW
ND = Hone detected at RL {Reporting Limit) . Rl unita earns as result
Reeulta reported in ppm expreaaed on air-dried soil basis.
cc:
Plate C-1
5. BABCOCK
& SONS, INC.
Environmental Laboratory Orttfcattor ni56
6100 Quail Valley Court Rtorsldft. CA 92507-0704
P.O. Box 432 Riversida. CA 92502-0432
PH (909) 653-3351 FAX (909) 653-1682
e-mail: eebsalesBaol.cann
www.balxocktab8.oyn
2277
Client;
GeoSoila, Inc.
5741 Palmer Way
Carlsbad,CA 92008
Client I.D.:
Site:
Description:
Matrix:
Constituent
Saturated Paste pH
VajM* ®fc*iuzV&&t
Redox Potential
sitil^de-l 'j^Y,, ' ''"?"')
Saturated Resistivity
TP-6OQ-2.2
WO#2588-A-SC
aoil-ag
Raoult
7.0
IS.'
210
,1300
Date Reported: 12/02/98
Collected By:
Date: 11/19/98
Time: 0000
Submitted By: Courier
Date: 11/20/98
Time: 0845
Data /
Itat&od gli_ Aaalyat
unita 8-1.10 W.Statea 0.
jjp»(i > -, 3J06, €3«0flf', -\ ''*. W
mV 3M 2580 1.
t3towsp',«; >ytos ^luii«» ,„ <
ohm-cm 8M 2520B 0.
981201/BW
SflWCIi^K'981201/BW
98i3i7i/BW
981201/BW
ND = None detected at Rt, (Reporting Limit) . RL unita same as result.
CC:
r
Plate C-2
E
C
C
C
£
** APPENDIX D
*• GENERAL EARTHWORK AND GRADING GUIDELINES
C
C
c;:
c
c
c :
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t
c
c
I
GENERAL EARTHWORK AND GRADING GUIDELINES
General
These guidelines present general procedures and requirements for earthwork and grading
as shown on the approved grading plans, including preparation of areas to filled,
placement of fill, installation of subdrains and excavations. The recommendations
contained in the geotechnical report are part of the earthwork and grading guidelines and
would supersede the provisions contained hereafter in the case of conflict. Evaluations
performed by the consultant during the course of grading may result in new
recommendations which could supersede these guidelines or the recommendations
contained in the geotechnical report.
The contractor is responsible for the satisfactory completion of all earthwork in accordance
with'provisions of the project plans and specifications. The project soil engineer and
engineering geologist (geotechnical consultant) or their representatives should provide
observation and testing services, and geotechnical consultation during the duration of the
project.
EARTHWORK OBSERVATIONS AND TESTING
Geotechnical Consultant
Prior to the commencement of grading, a qualified geotechnical consultant (soil engineer
and engineering geologist) should be employed for the purpose of observing earthwork
procedures and testing the fills for conformance with the recommendations of the
geotechnical report, the approved grading plans, and applicable grading codes and
ordinances.
The geotechnical consultant should provide testing and observation so that determination
may be made that the work is being accomplished as specified. It is the responsibility of
the contractor to assist the consultants and keep them apprised of anticipated work
schedules and changes, so that they may schedule their personnel accordingly.
All clean-outs, prepared ground to receive fill, key excavations, and subdrains should be
observed and documented by the project engineering geologist and/or soil engineer prior
to placing and fill. It is the contractors^ responsibility to notify the engineering geologist
and soil engineer when such areas are ready for observation.
Laboratory and Field Tests
Maximum dry density tests to determine the degree of compaction should be performed
in accordance with American Standard Testing Materials test method ASTM designation
D-1557-78. Random field compaction tests should be performed in accordance with test
method ASTM designation D-1556-82, D-2937 or D-2922 and D-3017, at intervals of
approximately 2 feet of fill height or every 100 cubic yards of fill placed. These criteria
GeoSoils, Inc.
would vary depending on the soil conditions and the size of the project. The location and
frequency of testing would be at the discretion of the geotechnical consultant.
Contractor's Responsibility
All clearing, site preparation, and earthwork performed on the project should be conducted
by the contractor, with observation by geotechnical consultants and staged approval by
the governing agencies, as applicable. It is the contractor's responsibility to prepare the
ground surface to receive the fill, to the satisfaction of the soil engineer, and to place,
spread, moisture condition, mix and compact the fill in accordance with the
recommendations of the soil engineer. The contractor should also remove all major non-
earth material considered unsatisfactory by the soil engineer.
It is the sole responsibility of the contractor to provide adequate equipment and methods
to accomplish the earthwork in accordance with applicable grading guidelines, codes or
agency ordinances, and approved grading plans. Sufficient watering apparatus and
compaction equipment should be provided by the contractor with due consideration for
the fill material, rate of placement, and climatic conditions. If, in the opinion of the
geotechnical consultant, unsatisfactory conditions such as questionable weather,
excessive oversized rock, or deleterious material, insufficient support equipment, etc., are
resulting in a quality of work that is not acceptable, the consultant will inform the
contractor, and the contractor is expected to rectify the conditions, and if necessary, stop
work until conditions are satisfactory.
During construction, the contractor shall properly grade all surfaces to maintain good
drainage and prevent ponding of water. The contractor shall take remedial measures to
control surface water and to prevent erosion of graded areas until such time as permanent
drainage and erosion control measures have been installed.
SITE PREPARATION
All major vegetation, including brush, trees, thick grasses, organic debris, and other
deleterious material should be removed and disposed of off-site. These removals must be
concluded prior to placing fill. Existing fill, soil, alluvium, colluvium, or rock materials
determined by the soil engineer or engineering geologist as being unsuitable in-place
should be removed prior to fill placement. Depending upon the soil conditions, these
materials may be reused as compacted fills. Any materials incorporated as part of the
compacted fills should be approved by the soil engineer.
Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic
tanks, wells, pipelines, or other structures not located prior to grading are to be removed
or treated in a manner recommended by the soil engineer. Soft, dry, spongy, highly
fractured, or otherwise unsuitable ground extending to such a depth that surface
processing cannot adequately improve the condition should be over-excavated down to
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 2
GeoSoils, Inc.
firm ground and approved by the soil engineer before compaction and filling operations
continue. Overexcavated and processed soils which have been properly mixed and
moisture conditioned should be re-compacted to the minimum relative compaction as
specified in these guidelines.
Existing ground which is determined to be satisfactory for support of the fills should be
scarified to a minimum depth of 6 inches or as directed by the soil engineer. After the
scarified ground is brought to optimum moisture content or greater and mixed, the
materials should be compacted as specified herein. If the scarified zone is grater that 6
inches in depth, it may be necessary to remove the excess and place the material in lifts
restricted to about 6 inches in compacted thickness.
Existing ground which is not satisfactory to support compacted fill should be over-
excavated as required in the geotechnical report or by the on-site soils engineer and/or
engineering geologist. Scarification, disc harrowing, or other acceptable form of mixing
should continue until the soils are broken down and free of large lumps or clods, until the
working surface is reasonably uniform and free from ruts, hollow, hummocks, or other
uneven features which would inhibit compaction as described previously.
Where fills are to be placed on ground with slopes steeper than 5:1 (horizontal to vertical),
the ground should be stepped or benched. The lowest bench, which will act as a key,
should be a minimum of 15 feet wide and should be at least 2 feet deep into firm material,
and approved by the soil engineer and/or engineering geologist. In fill over cut slope
conditions, the recommended minimum width of the lowest bench or key is also 15 feet
with the key founded on firm material, as designated by the Geotechnical Consultant. As
a general rule, unless specifically recommended otherwise by the Soil Engineer, the
minimum width of fill keys should be approximately equal to 1/2 the height of the slope.
Standard benching is generally 4 feet (minimum) vertically, exposing firm, acceptable
material. Benching may be used to remove unsuitable materials, although it is understood
that the vertical height of the bench may exceed 4 feet. Pre-stripping may be considered
for unsuitable materials in excess of 4 feet in thickness.
All areas to receive fill, including processed areas, removal areas, and the toe of fill
benches should be observed and approved by the soil engineer and/or engineering
geologist prior to placement of fill. Fills may then be properly placed and compacted until
design grades (elevations) are attained.
COMPACTED FILLS
Any earth materials imported or excavated on the property may be utilized in the fill
provided that each material has been determined to be suitable by the soil engineer.
These materials should be free of roots, tree branches, other organic matter or other
deleterious materials. All unsuitable materials should be removed from the fill as directed
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 3
GeoSoils, Inc.
by the soil engineer. Soils of poor gradation, undesirable expansion potential, or
substandard strength characteristics may be designated by the consultant as unsuitable
and may require blending with other soils to serve as a satisfactory fill material.
Fill materials derived from benching operations should be dispersed throughout the fill
area and blended with other bedrock derived material. Benching operations should not
result in the benched material being placed only within a single equipment width away
from the fill/bedrock contact.
Oversized materials defined as rock or other irreducible materials with a maximum
dimension greater than 12 inches should not be buried or placed in fills unless the location
of materials and disposal methods are specifically approved by the soil engineer.
Oversized material should betaken off-site or placed in accordance with recommendations
of the soil engineer in areas designated as suitable for rock disposal. Oversized material
should not be placed within 10 feet vertically of finish grade (elevation) or within 20 feet
horizontally of slope faces.
To facilitate future trenching, rock should not be placed within the range of foundation
excavations, future utilities, or underground construction unless specifically approved by
the soil engineer and/or the developers representative.
If import material is required for grading, representative samples of the materials to be
utilized as compacted fill should be analyzed in the laboratory by the soil engineer to
determine its physical properties. If any material other than that previously tested is
encountered during grading, an appropriate analysis of this material should be conducted
by the soil engineer as soon as possible.
Approved fill material should be placed in areas prepared to receive fill in near horizontal
layers that when compacted should not exceed 6 inches in thickness. The soil engineer
may approve thick lifts if testing indicates the grading procedures are such that adequate
compaction is being achieved with lifts of greater thickness. Each layer should be spread
evenly and blended to attain uniformity of material and moisture suitable for compaction.
Fill layers at a moisture content less than optimum should be watered and mixed, and wet
fill layers should be aerated by scarification or should be blended with drier material.
Moisture condition, blending, and mixing of the fill layer should continue until the fill
materials have a uniform moisture content at or above optimum moisture.
After each layer has been evenly spread, moisture conditioned and mixed, it should be
uniformly compacted to a minimum of 90 percent of maximum density as determined by
ASTM test designation, D-1557-78, or as otherwise recommended by the soil engineer.
Compaction equipment should be adequately sized and should be specifically designed
for soil compaction or of proven reliability to efficiently achieve the specified degree of
compaction.
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 4
GeoSoils, Inc.
Where tests indicate that the density of any layer of fill, or portion thereof, is below the
required relative compaction, or improper moisture is in evidence, the particular layer or
portion shall be re-worked until the required density and/or moisture content has been
attained. No additional fill shall be placed in an area until the last placed lift of fill has been
tested and found to meet the density and moisture requirements, and is approved by the
soil engineer.
Compaction of slopes should be accomplished by over-building a minimum of 3 feet
horizontally, and subsequently trimming back to the design slope configuration. Testing
shall be performed as the fill is elevated to evaluate compaction as the fill core is being
developed. Special efforts may be necessary to attain the specified compaction in the fill
slope zone. Final slope shaping should be performed by trimming and removing loose
materials with appropriate equipment. A final determination of fill slope compaction should
be based on observation and/or testing of the finished slope face. Where compacted fill
slopes are designed steeper than 2:1 (horizontal to vertical), specific material types, a
higher minimum relative compaction, and special grading procedures, may be
recommended.
If an alternative to over-building and cutting back the compacted fill slopes is selected,
then special effort should be made to achieve the required compaction in the outer 10 feet
of each lift of fill by undertaking the following:
2. An extra piece of equipment consisting of a heavy short shanked sheepsfoot should
be used to roll (horizontal) parallel to the slopes continuously as fill is placed. The
sheepsfoot roller should also be used to roll perpendicular to the slopes, and
extend out over the slope to provide adequate compaction to the face of the slope.
2. Loose fill should not be spilled out over the face of the slope as each lift is
compacted. Any loose fill spilled over a previously completed slope face should be
trimmed off or be subject to re-rolling.
3. Field compaction tests will be made in the outer (horizontal) 2 to 8 feet of the slope
at appropriate vertical intervals, subsequent to compaction operations.
4. After completion of the slope, the slope face should be shaped with a small tractor
and then re-rolled with a sheepsfoot to achieve compaction to near the slope face.
Subsequent to testing to verify compaction, the slopes should be grid-rolled to
achieve compaction to the slope face. Final testing should be used to confirm
compaction after grid rolling.
5. Where testing indicates less than adequate compaction, the contractor will be
responsible to rip, water, mix and re-compact the slope material as necessary to
achieve compaction. Additional testing should be performed to verify compaction.
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 5
GeoSoils, Inc.
6. Erosion control and drainage devices should be designed by the project civil
engineer in compliance with ordinances of the controlling governmental agencies,
and/or in accordance with the recommendation of the soil engineer or engineering
geologist.
SUBDRA1N INSTALLATION
Subdrains should be installed in approved ground in accordance with the approximate
alignment and details indicated by the geotechnical consultant. Subdrain locations or
materials should not be changed or modified without approval of the geotechnical
consultant. The soil engineer and/or engineering geologist may recommend and direct
changes in subdrain line, grade and drain material in the field, pending exposed
conditions. The location of constructed subdrains should be recorded by the project civil
engineer.
EXCAVATIONS
Excavations and cut slopes should be examined during grading by the engineering
geologist. If directed by the engineering geologist, further excavations or overexcavation
and re-filling of cut areas should be performed and/or remedial grading of cut slopes
should be performed. When fill over cut slopes are to be graded, unless otherwise
approved, the cut portion of the slope should be observed by the engineering geologist
prior to placement of materials for construction of the fill portion of the slope.
The engineering geologist should observe all cut slopes and should be notified by the
contractor when cut slopes are started.
If, during the course of grading, unforeseen adverse or potential adverse geologic
conditions are encountered, the engineering geologist and soil engineer should
investigate, evaluate and make recommendations to treat these problems. The need for
cut slope buttressing or stabilizing should be based on in-grading evaluation by the
engineering geologist, whether anticipated or not.
Unless otherwise specified in soil and geological reports, no cut slopes should be
excavated higher or steeper than that allowed by the ordinances of controlling
governmental agencies. Additionally, short-term stability of temporary cut slopes is the
contractors responsibility.
Erosion control and drainage devices should be designed by the project civil engineer and
should be constructed in compliance with the ordinances of the controlling governmental
agencies, and/or in accordance with the recommendations of the soil engineer or
engineering geologist.
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 6
GeoSoils, Inc.
COMPLETION
Observation, testing and consultation by the geotechnical consultant should be conducted
during the grading operations in order to state an opinion that all cut and filled areas are
graded in accordance with the approved project specifications.
After completion of grading and after the soil engineer and engineering geologist have
finished their observations of the work, final reports should be submitted subject to review
by the controlling governmental agencies. No further excavation or filling should be
undertaken without prior notification of the soil engineer and/or engineering geologist.
All finished cut and fill slopes should be protected from erosion and/or be planted in
accordance with the project specifications and/or as recommended by a landscape
architect. Such protection and/or planning should be undertaken as soon as practical after
completion of grading.
JOB SAFETY
General
At GeoSoils, Inc. (GSI) getting the job done safely is of primary concern. The following is
the company's safety considerations for use by all employees on multi-employer
construction sites. On ground personnel are at highest risk of injury and possible fatality
on grading and construction projects. GSI recognizes that construction activities will vary
on each site and that site safety is the prime responsibility of the contractor; however,
everyone must be safety conscious and responsible at all times. To achieve our goal of
avoiding accidents, cooperation between the client, the contractor and GSI personnel must
be maintained.
In an effort to minimize risks associated with geotechnical testing and observation, the
following precautions are to be implemented for the safety of field personnel on grading
and construction projects:
Safety Meetings: GSI field personnel are directed to attend contractors regularly
scheduled and documented safety meetings.
Safety Vests: Safety vests are provided for and are to be worn by GSI personnel at
all times when they are working in the field.
Safety Flags: Two safety flags are provided to GSI field technicians; one is to be
affixed to the vehicle when on site, the other is to be placed atop the
spoil pile on all test pits.
Spectrum Communities Appendix 0
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GeoSoils, Inc.
Flashing Lights: All vehicles stationary in the grading area shall use rotating or flashing
amber beacon, or strobe lights, on the vehicle during all field testing.
While operating a vehicle in the grading area, the emergency flasher
on the vehicle shall be activated.
In the event that the contractor's representative observes any of our personnel not
following the above, we request that it be brought to the attention of our office.
Test Pits Location. Orientation and Clearance
The technician is responsible for selecting test pit locations. A primary concern should be
the technicians's safety. Efforts will be made to coordinate locations with the grading
contractors authorized representative, and to select locations following or behind the
established traffic pattern, preferably outside of current traffic. The contractors authorized
representative (dump man, operator, supervisor, grade checker, etc.) should direct
excavation of the pit and safety during the test period. Of paramount concern should be
the soil technicians safety and obtaining enough tests to represent the fill.
Test pits should be excavated so that the spoil pile is placed away form oncoming traffic,
whenever possible. The technician's vehicle is to be placed next to the test pit, opposite
the spoil pile. This necessitates the fill be maintained in a driveable condition.
Alternatively, the contractor may wish to park a piece of equipment in front of the test
holes, particularly in small fill areas or those with limited access.
A zone of non-encroachment should be established for all test pits. No grading equipment
should enter this zone during the testing procedure. The zone should extend
approximately 50 feet outward from the center of the test pit. This zone is established for
safety and to avoid excessive ground vibration which typically decreased test results.
When taking slope tests the technician should park the vehicle directly above or below the
test location. If this is not possible, a prominent flag should be placed at the top of the
slope. The contractor's representative should effectively keep all equipment at a safe
operation distance (e.g. 50 feet) away from the slope during this testing.
The technician is directed to withdraw from the active portion of the fill as soon as possible
following testing. The technician's vehicle should be parked at the perimeter of the fill in
a highly visible location, well away from the equipment traffic pattern.
The contractor should inform our personnel of all changes to haul roads, cut and fill areas
or other factors that may affect site access and site safety.
In the event that the technicians safety is jeopardized or compromised as a result of the
contractors failure to comply with any of the above, the technician is required, by company
policy, to immediately withdraw and notify his/her supervisor. The grading contractors
representative will eventually be contacted in an effort to effect a solution. However, in the
Spectrum Communities Appendix D
File: e:\wp7\2500\2588a.pgi Page 8
GeoSoils, Inc.
interim, no further testing will be performed until the situation is rectified. Any fill place can
be considered unacceptable and subject to reprocessing, recompaction or removal.
In the event that the soil technician does not comply with the above or other established
safety guidelines, we request that the contractor brings this to his/her attention and notify
this office. Effective communication and coordination between the contractors
representative and the soils technician is strongly encouraged in order to implement the
above safety plan.
Trench and Vertical Excavation
It is the contractor's responsibility to provide safe access into trenches where compaction
testing is needed.
Our personnel are directed not to enter any excavation or vertical cut which 1) is 5 feet or
deeper unless shored or laid back, 2) displays any evidence of instability, has any loose
rock or other debris which could fall into the trench, or 3) displays any other evidence of
any unsafe conditions regardless of depth.
All trench excavations or vertical cuts in excess of 5 feet deep, which any person enters,
should be shored or laid back.
Trench access should be provided in accordance with CAL-OSHA and/or state and local
standards. Our personnel are directed not to enter any trench by being lowered or "riding
down" on the equipment.
If the contractor fails to provide safe access to trenches for compaction testing, our
company policy requires that the soil technician withdraw and notify his/her supervisor.
The contractors representative will eventually be contacted in an effort to effect a solution.
All backfill not tested due to safety concerns or other reasons could be subject to
reprocessing and/or removal.
If GSI personnel become aware of anyone working beneath an unsafe trench wall or
vertical excavation, we have a legal obligation to put the contractor and owner/developer
on notice to immediately correct the situation. If corrective steps are not taken, GSI then
has an obligation to notify CAL-OSHA and/or the proper authorities.
Spectrum Communities Appendix D
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GeoSoilSj Inc.
CANYON SUBDRAIN DETAIL
TYPE A
PROPOSED COMPACTED FILL
•NATURAL GROUND
-COLLUVIUM AND ALLUVIUM (REMOVE) x-_x
BEDROCK
TYPICAL BENCHING
ALTERNATIVES
TYPE B
PROPOSED COMPACTED FILL .'' A
NATURAL GROUND
COLLUVIUM AND ALLUVIUM (REMOVE)
BEDROCK
TYPICAL BENCHING
ALTERNATIVES
NOTE: ALTERNATIVES. LOCATION AND EXTENT OF SU80RAINS SHOULD BE DETERMINED
BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST DURING GRADING.
PLATE EG-1
CANYON SUBDRAIN ALTERNATE DETAILS
ALTERNATE 1: PERFORATED PIPE AND FILTER MATERIAL
12* MINIMUM
^1
MINIMUM
A-1
FILTER MATERIAL
SIEVE StZE PERCENT PASSING
. 100
90-100
40-100
25-40.
18-33
-.5-15
.0-7
0-3-
1 INCH
3/4 INCH
3/8 INCH
NO. 4
NO. 8
NO. 30
"NO. 50
NO. 200
FILTER MATERIAL MINIMUM VOLUME OF 9 FT.1
/LINEAR FT. 6' t ABS OR PVC PIPE OR APPROVED 3
SUBSTITUTE WITH MINIMUM 8 (1/4-0 PERFS. A
LINEAR FT. IN BOTTOM HALF OF Pipf.
ASTM D2751. SDR 35 OR ASTM D1527. SCHD, 40
ASTM D3034. SDR 35 OR ASTM D1785. SCHD. 40
FOR CONTINUOUS RUN IN EXCESS OF 5&0 FT.
USE 8'^ PIPE
' 6* MINIMUM
B-1
ALTERNATE 2: PERFORATED PIPE, GRAVEL AND. FILTER FABRIC
*£"T^M?N1MUM OVERLAP 6" MINIMUM OVERLAP
^*"— jrf
^^ -55TTT
6'MINIMUM COVER
'==*• MINIMUM BEDDING *' MINIMUM BEDDING-
GRAVEL'MATERIAL 9 FT3/LINEAR FT.
PERFORATED PIPE: SEE ALTERNATE 1
GRAVEL: CLEAN 3/4 INCH ROCX OR APPROVED SUBSTITUTE
FILTER FABRIC: MIRAFI uo OR APPROVED SUBSTITUTE
A-2
PLATE EG-2
DETAIL FOR FILL SLOPE TOEING OUT
ON FLAT ALLUVIATED CANYON
TOE OF SLOPE AS SHOWN ON GRADING PLAN
.ORIGINAL GROUND SURFACE TO BE
RESTORED WITH COMPACTED FILL
COMPACTED RLL
ORIGINAL GROUND SURFACE
BACKCUTS VARIES. FOR DEEP REMOVALS.
BACKCUT ^VKSHOULD BE MADE NO
STEEPER THAN\1:1 OR AS NECESSARY £
FOR SAFETY ^^CONSIDERATIONS.,'
ANTICIPATED ALLUVIAL REMOVAL
DEPTH PER SOIL ENGINEER.
PROVIDE A 1:1 MINIMUM PROJECTION FROM T0€ OF
SLOPE AS SHOWN ON GRADING PLAN TO THE RECOMMENDED
REMOVAL DEPTH. SLOPE HEIGHT. SITE CONDITIONS AND/OR
LOCAL CONDITIONS COULD DICTATE FLATTER PROJECTIONS.
REMOVAL ADJACENT TO EXISTING FILL
ADJOINING CANYON RLL
PROPOSED ADDITIONAL COMPACTED FILL
COMPACTED FILL LIMITS LINE
v TEMPORARY COMPACTED FILL
Y FOR DRAINAGE ONLY
Q a I (TO BE REMOVED)Qaf
(EXISTING COMPACTED FILL)
%$]]!%$%
'ACTED F1LU v N% ^- .
taedfa*^W^
r/-fe/^^/7
7\\V4^V / Tn Rc REMOVED BEFORETO BE REMOVED BEFORE
PLACING ADDITIONAL
COMPACTED FILL
LEGEND
Qaf ARTIFICIAL FILL
Qal ALLUVIUM
PLATE EG-3
f i f ! I 1 I 1 r 1 * 1 f I I ! ! I I 1 I ! f i ! ! t 1 !
TYPICAL STABILIZATION / BUTTRESS FILL DETAIL
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OUTLETS TO BE SPACED AT 100'MAXIMUM INTERVALS. AND SHALL EXTEND
12' BEYOND THE FACE OF SLOPE AT TIME OF. ROUGH GRADING COMPLETION.
DESIGN FINISH SLOPE
4-
15'MINIMUM
BLANKET FILL IF RECOMMENDED
BY THE SOIL ENGINEER
^2% GRADIENT
10'MINIMUM
25'MAXIMU>
^' ' *J^%* *
TYPICAL BENCHING\ I
BUTTRESS OR SIDEHILL FILL I V t,' DIAMETER NON-PERFORATED OUTLET PIPE
BACKDRAIN (SEE ALTERNATIVES)
BEDROCK
HEEL
= 15'MINIMUM OR H/2
3'MINIMUM KEY DEPTH
I ! f ! i I i i
TYPICAL STABILIZATION / BUTTRESS SUBDRAIN DETAIL
I,' MINIMUM 2' MINIMUM
PIPE
4' MINIMUM
PIPE
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01
1' MINIMUM
FILTER MATERIAL: MINIMUM OF FIVE FtVLINEAR Ft OF PIPF
OR FOUR Ft'/LINEAR Ft OF PIPE WHEN PLACED IN SQUARE
CUT TRENCH.
ALTERNATIVE IN LIEU OF FILTER MATERIAL: GRAVEL MAY BE
ENCASED IN APPROVED FILTER FABRIC. FILTER FABRIC
SHALL BE MIRAFI UO OR EQUIVALENT. FILTER FABRIC
SHALL BE LAPPED A MINIMUM OF 12" ON ALL JOINTS.
MINIMUM 4' DIAMETER PIPE: ABS-ASTM D-2751. SDR 35
OR ASTM D-1527 SCHEDULE 40 PVC-ASTM D-3034.
SDR 35 OR ASTM D-1785 SCHEDULE 40 WITH A CRUSHING
STRENGTH OF 1,000 POUNDS MINIMUM. AND A MINIMUM OF
8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE
INSTALLED WITH PERFORATIONS OF BOTTOM OF PIPE.
PROVIDE CAP AT UPSTREAM END OF PIPE. SLOPE AT 2%
TO OUTLET PIPE. OUTLET PIPE TO BE CONNECTED TO
SUBDRAIN PIPE WITH TEE OR ELBOW.
NOTE: 1. TRENCH FOR OUTLET PIPES TO BE BACKFILLED
WITH ON-SITE SOIL.
2. BACKDRAINS AND LATERAL DRAINS SHALL BE
LOCATED AT ELEVATION OF EVERY BENCH DRAIN.
FIRST DRAIN LOCATED AT ELEVATION JUST ABOVE
LOWER LOT GRADE. ADDITIONAL DRAINS MAY BE
REQUIRED AT THE DISCRETION OF THE SOILS
ENGINEER AND/OR ENGINEERING GEOLOGIST.
FILTER MATERIAL SHALL BE OF
THE FOLLOWING SPECIFICATION
OR AN APPROVED EQUIVALENT:
SIEVE SIZE PERCENT PASSING
1 INCH
3/4 INCH
3/8 INCH
NO. 4
NO. 8
NO. 30
NO. 50
NO. 200
100
90-100
40-100
25-40
18-33
5-15
0-7
0-3
GRAVEL SHALL BE OF THE
FOLLOWING SPECIFICATION OR
AN APPROVED EQUIVALENT:
SIEVE SIZE PERCENT PASSING
1 1/2 INCH
NO. 4
NO. 200
100
50
8
SAND EQUIVALENT: MINIMUM OF so
I i ! 1 I I I ! f ! ! f 1 I 1 I I i I i f
FILL OVER NATURAL DETAIL
SIDEHILL FILL
PROPOSED GRADE
TOE OF SLOPE AS SHOWN ON GRADING PLAN
PROVIDE A 1:1 MINIMUM PROJECTION FROM
DESIGN TOE OF SLOPE TO TOE OF KEY
AS SHOWN ON AS BUILT
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CD
COMPACTED FILL
MAINTAIN MINIMUM 15' WIDTH
SLOPE TO BENCH/BACKCUT
NATURAL SLOPE TO
BE RESTORED WITH
COMPACTED FILL
BACKCUT VARIES
'MINIMUM
BENCH WIDTH MAY VARY
"Tr. MINIMUM
NOTE: 1. WHERE THE NATURAL SLOPE APPROACHES OR EXCEEDS THE
2'X 3'MINIMUM KEY DEPTH
2'MINIMUM IN BEDROCK OR
APPROVED MATERIAL.
DESIGN SLOPE RATIO. SPECIAL RECOMMENDATIONS WOULD BE
PROVIDED BY THE SOILS ENGINEER.
2. THE NEED FOR AND DISPOSITION OF DRAINS WOULD BE DETERMINED
BY THE SOILS ENGINEER BASED UPON EXPOSED CONDITIONS.
f 1 I
FILL OVER CUT DETAIL
H
CUT/FILL CONTACT
1. AS SHOWN ON GRADING PLAN
2. AS SHOWN ON AS BUILT
MAINTAIN MINIMUM 15'FILL SECTION FROM
BACKCUT TO FACE OF FINISH SLOPE
PROPOSED GRADE
ORIGINAL TOPOGRAPHY
^ BEDROCK OR APPROVED MATERIAL
ILOWEST BENCH WIDTH
15'MINIMUM OR H/2
BENCH WIDTH MAY VARY
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NOTE: THE CUT PORTION OF THE SLOPE SHOULD BE EXCAVATED AND
EVALUATED BY THE SOILS ENGINEER AND/OR ENGINEERING
GEOLOGIST PRIOR TO CONSTRUCTING THE FILL PORTION.
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STABILIZATION FILL FOR UNSTABLE MATERIAL
EXPOSED IN PORTION OF CUT SLOPE
REMOVE: UNSTABLE MATERIAL
REMOVE: UNSTABLE
MATERIAL
PROPOSED FINISHED GRADEfv>S\
UNWEATHERED BEDROCK
OR APPROVED MATERIAL
COMPACTED STABILIZATION FILL
V MINIMUM TILTED BACK
IF RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING
GEOLOGIST. THE REMAINING CUT PORTION OF THE SLOPE MAY
i
REQUIRE REMOVAL AND REPLACEMENT WITH COMPACTED FILL
NOTE: 1. SUBDRAINS ARE NOT REQUIRED UNLESS SPECIFIED BY SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST,
2. -W SHALL BE EQUIPMENT WIDTH (15') FOR SLOPE HEIGHTS LESS THAN 25 FEET. FOR SLOPES GREATER
THAN 25 FEET "W SHALL BE DETERMINED BY THE PROJECT SOILS ENGINEER AND /OR ENGINEERING
GEOLOGIST. AT NO TIME SHALL *W BE LESS THAN H/2.
I ! f
SKIN FILL OF NATURAL GROUND
ORIGINAL SLOPE
>ROPOSED FINISH GRADE
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ID
15'MINIMUM TO BE MAINTAINED FROM
PROPOSED FINISH SLOPE FACE TO BACKCUT
PROPOSED FINISH SLOPE BEDROCK OR APPROVED MATERIAL
MINIMUM
KEY DEPTH
NIMUM KEY W DTH
NOTE: 1. THE NEED AND DISPOSITION OF DRAINS WILL BE DETERMINED! BY THE SOILS ENGINEER AND/OR
ENGINEERING GEOLOGIST BASED ON FIELD CONDITIONS.
2. PAD OVEREXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED TO BE
NECESSARY BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST,
I I
DAYLIGHT CUT LOT DETAIL
PROPOSED FINISH GRADE
3' MINIMUM BLANKET FILL
TYPICAL BENCHING
RECONSTRUCT COMPACTED FILL SLOPE AT 2:1 OR FLATTER
(MAY INCREASE OR DECREASE PAD AREA).
OVEREXCAVATE AND RECOMPACT
REPLACEMENT FILL
AVOID AND/OR CLEAN UP SPILLAGE OF
MATERIALS ON THE NATURAL SLOPE
BEDROCK OR APPROVED MATERIAL
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NOTE: 1. SUBORAIN AND KEY WIDTH REQUIREMENTS WILL BE DETERMINED BASED ON EXPOSED SUBSURFACE
CONDITIONS AND THICKNESS OF OVERBURDEN.
2. PAD OVER EXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED NECESSARY BY
THE SOILS ENGINEER AND/OR THE ENGINEERING GEOLOGIST.
o
TRANSITION LOT DETAIL
CUT LOT (MATERIAL TYPE TRANSITION)
NATURAL GRADE
COMPACTED RLL
OVEREXCAVATE AND RECOMPACT
'\\W\\V//\^AW\\># 3' MINIMUM*
UNWEATHERED BEDROCK OR APPROVED MATERIAL
TYPICAL BENCHING
CUT-FILL LOT (DAYLIGHT TRANSITION}
OVEREXCAVATE
AND RECOMPACT
UNWEATHERED BEDROCK OR APPROVED MATERIAL
L TYPICAL BENCHING
NOTE' * DEEPER OVEREXCAVATION MAY BE RECOMMENDED BY THE SOILS ENG.NEER
AND/OR ENGINEERING GEOLOGIST IN STEEP CUT-FILL TRANSITION AREAS.
PLATE EG-11
OVERSIZE ROCK DISPOSAL
VIEWS ARE DIAGRAMMATIC ONLY. ROCX SHOULD NOT TOUCH
AND VOIDS SHOULD BE COMPLETELY FILLED IN.
VIEW NORMAL TO SLOPE FACE
PROPOSED FINISH GRADE
10* MINIMUM {0
co CO
INIMUM (A)
* +co (30
CO Cf=>
MINIMUM ,.
jj? MtNIMUM (CT
(Fl
co
(Gi
CO
^^^^n\\^\^\\^^\v^^/^^\^^
BEDROCK' 6R APPROVED MATERIAL
VIEW PARALLEL TO SLOPE FACE
PROPOSED RNISH GRADE
BEDROCK OR APPROVED MATERIAL
^/AXV/A\V//<<V^\\\
NOTE: (A) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET.
(B) HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SEE AND TYPE OF
EQUIPMENT USED. LENGTH OF WINDROW SHALL BE NO GREATER THAN 100'
MAX 1MLJ M
(CJ IF APPROVED BY THE SOILS ENGINEER AND/OR ENGINEERNG GEOLOGIST..WINDROWS MAY BE PUCED DIRECTLY ON COMPETENT MATERIALS OR BEDROCK
PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION.
(D) ORIENTATION OF WINDROWS MAY VARY BUT SHALL BE AS RECOMMENDED BY
THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. STAGGERING OF
WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED.
IE) CLEAR AREA FOR UTILITY TRENCHES. FOUNDATIONS AND SWIMMING POOLS.
IF) VOIDS IN WINDROW SHALL BE FILLED BY FLOODING GRANULAR SOIL INTO PLACE
GRANULAR SOIL SHALL BE ANY SOIL WHICH HAS A UNIFIED SOIL CLASSIFICATION
?J?TEM IUBC 29-1) DESIGNATION OF SM. SP. SW. GP. OR GW. ALL RLL OVER
AND AROUND ROCK WINDROW SHALL BE? COMPACTED TO 90% RELATIVE
'COMPACTION.
(G) AFTER RLL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE UFT
OF FILL COVERING WINDROW. WINDROW SHALL BE PROOF ROLLED WITH A 0-9
DOZER OR EQUIVALENT.
(H) OVERSIZED ROCX IS DEFINED AS LARGER THAN 12", AND LESS THAN 4 FEET
IN SEE/ pLATE EG-12
ROCK DISPOSAL PITS
FILL LIFTS COMPACTED OVER
ROCK AFTER EMBEDMENT
COMPACTED FILL
GRANULAR MATERIAL
— — — —-j
SEE OF EXCAVATION TO BE COMMENSURATE
WITH ROCK SEE.
NOTE: 1. LARGE ROCK IS DEFINED AS ROCK LARGER THAN 4 FEET IN MAXIMUM SEE.
2. PIT IS EXCAVATED INTO COMPACTED FILL TO A DEPTH EQUAL TO 1/2 OF
ROCK SEE.
3. GRANULAR SOIL SHOULD BE PUSHED INTO PIT AND DENSIF1EO BY FLOODING.
USE A SHEEPSFOOT AROUND ROCK TO AID IN COMPACTION.
A. A MINIMUM OF L FEET OF REGULAR COMPACTED FILL SHOULD OVERLIE
EACH PIT.
5. PITS SHOULD BE SEPARATED BY AT LEAST 15 FEET HORIZONTALLY.
6. PITS SHOULD NOT BE PLACED WITHIN 20 FEET OF ANY FILL SLOPE.
7. PITS SHOULD ONLY BE USED IN DEEP FILL AREAS.
PLATE EG-13
SETTLEMENT PLATE AND RISER DETAIL
2'X 2'X 1/4' STEEL PLATE
STANDARD 3Um PIPE NIPPLE WELDED TO TOP
OF PLATE.
3/4' X 5'GALVANIZED PIPE. STANDARD PIPE
THREADS TOP AND BOTTOM. EXTENSIONS
THREADED ON BOTH ENDS AND ADDED IN 5*
INCREMENTS.
3 INCH SCHEDULE 40 PVC PIPE SLEEVE. ADD IN
5* INCREMENTS WITH GLUE JOINTS.
FINAL
T
i«•••j
5'
2—
r
>
_//
^^^^M
1
r
GRADE — _^___— —
1
1
1
— >--V- -•
-i-V
1— «*-
^ 5' *
/
/
1
MAINTAIN 5' CLEARANCE OF HEAVY EQUIPMENT.
L_ MECHANICALLY HAND COMPACT IN 2' VERTICAL
_\~ —^v- LIFTS OR ALTERNATIVE SUITABLE TO AND
T ACCEPTED BY THE SOILS ENGINEER.
4 5- |
1
1 MECHANICALLY HAND COMPACT THE INITIAL 5*
^" VERTICAL WITHIN A 5' RADIUS OF PLATE BASE.^•"\
x^ >^
^N
\y
/
\.. . . . r;. ....... .7-. •/ • ;./ BOTTOM OF CLEANOU 1
V- '•'••••'• •' ' '•'•"uuiVunTe A MINIMUM V BEDDING OF COMPACTED SAND
NOTE:1. LOCATIONS OF SETTLEMENT;PLATES^SHOpULD BE CLEARLY MARKED AND READ,LY
VISIBLE {RED FLAGGED! TO EQUIPMENT OPERATORS BASE MQ
2. CONTRACTOR SHOULD'MAINTAIN' CLEARANtfc Uh^^ CLEARANCE AREA SHOULD
B^HAND IMPACTED™? ?REfficfQSPEClllCATK)NS OR COMPACTED BY ALTERNATIVE
3 iFTERV5E°wlRTICAUSOF^LLT CONTRACTOR SHOULD MA.NTAIN A 5'RAD.US
SEciZclLfHMANDS"MPAC INITIAL 2'OF F,LL PR.OR TO ESTABLISHING
TO THE SETTLEMENT PLATE OR EXTENSION RESULTING
WITHIN THE SPECIFIED CLEARANCE AREA. CONTRACTOR
BE RESPONSIBLE
5 :0NRAaESH°NATE DESIGNT^ND METHOD OF .NSTALLATION MAY BE PROV,DED AT THE
DISCRETION OF THE SOILS ENGINEER. _..__. -^ .
PLATE EG—14
TYPICAL SURFACE SETTLEMENT MONUMENT
RNISH GRADE
3/8' DIAMETER X 6' LENGTH
CARRIAGE BOLT OR EQUIVALENT
k-6" DIAMETER X 3 1/2* LENGTH HOLE
CONCRETE BACKFILL
PLATE EG-15
TEST PIT SAFETY DIAGRAM
SIDE VIEW
( NOT TO SCALE )
STESTP!T|
APPROXIMATE
CF TEST PIT
( NOT TO SCALE )
PLATE EG-16
OVERSIZE ROCK DISPOSAL
VIEW NORMAL TO SLOPE FACE
PROPOSED FINISH GRADE
20' MINIMUM
CO
15' MINIMUM (A"
)' MINIMUM (E)
oo oo
15'MINIMUM (A)<o—^°CO
CO
(G)
ooiFI
^^^
BEDROCK OR APPROVED MATERIAL
MINIMUM (C)
VIEW PARALLEL TO SLOPE FACE
PROPOSED FINISH GRADE
Tl 0'MINIMUM (E) .100'MAXIMUM (B\.
FROM
OR APPROVED MATERIAL
NOTE:
(Dl ?HE SofJsTNSlNEEFI AN/oSAEN6INEER.NG GEOLOGIST. STAGGERING OF
WINDROWS MS NOT NECESSARY ^gSgECOMMENDE^ ^^^ poQLS
CLEA AND AROuVo ^ROCK WINDROW SHALL BE COMPACTED TO 90%
{Gl
COMPACTED W.TH THE LIFT OFBE PROOF ROLLED WITH A
ROCX SHOULD NOT TOUCH
AN Voo SHOULD BE COMPLETELY FILLED IN. PLATE RD~1
ROCK DISPOSAL PITS
VIEWS ARE DIAGRAMMATIC ONLY. ROCX SHOULD NOT TOUCH
AND VOIDS SHOULD BE COMPLETELY FILLED IN.
FILL LIFTS COMPACTED OVER
ROCK AFTER EMBEDMENT
GRANULAR MATERIAL
COMPACTED FILL
SIZE OF EXCAVATION TO BE
COMMENSURATE WITH ROCK SIZE
ROCK DISPOSAL LAYERS
GRANULAR SOIL TO RLL VOIDS.-v
OENSIF1ED BY FLOODING ^
COMPACTED RLL
LAYER ONE ROCK HIGH
PROPOSED FINISH GRADE
MUM
PROFILE ALONG LAYER
LOPE FACE
MINIMUM OR BELOW LOWEST UTILJ
COOOCX3OCOOCOC
13'MINIMUM
CLEAR ZONE 20' MINIMUM
LAYER ONE ROCK HIGH
PLATE RD-2