HomeMy WebLinkAboutPRELIMINARY GEOTECHNICAL INVESTIGATION TORN RANCH PROPERTY OCT 1998 APPROVED
FOR PERMIT ISSUANCE
i SC F EKAS & ASSOCIATES. INC.
BY DATE
These plans have been reviewed for adher c . to the
applicable codes and ordinance Authorization is
hereby granted to issue a built! J permit pending
approval by all applicable City agei _, s.
LThe issuance or granting of a pt—mit based on approval of these plans shall not be construed to
(ITT
permit or approve any violation of the applicable
_ codes or ordinance. No permit presumed to give
i authority to violate or cancel the provisions of such
valid.
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Geotechnical • Geologic • Environmental
PRELIMINARY GEOTECHNICAL INVESTIGATION
10-ACRE PARCEL AND A PORTION OF ADJACENT PARCEL
_ TORN RANCH PROPERTY
CITY OF LAKE ELSINORE, RIVERSIDE COUNTY, CALIFORNIA
FOR
TORN RANCH BUILDERS, LLC
P.O. BOX 490
DEL MAR, CALIFORNIA 92014
OCTOBER 16, 1998 W. O. 2492-A-SC
s,
Geotechnical • Geologic • Environmental
24890 Jefferson Ave. Murrieta, California 92564 • (909) 677-9651 • FAX (909) 677-9301
October 16, 1998
W.O. 2492-A-SC
Torn Ranch Builders, LLC
P.O. Box 490
Del Mar, California 92014
Attention: Mr. Mike Finley
Subject: Preliminary Geotechnical Investigation, 10-acre Parcel and a Portion of
Adjacent Parcel, Torn Ranch Property, City of Lake Elsinore, Riverside
County, California
Dear Mr. Finley:
In accordance with your request and authorization, GeoSoils, Inc. (GSI) is pleased to
present the results of our preliminary geotechnical investigation of the subject site. The
purpose of the study was to evaluate the onsite soils and geologic conditions and their
effects on the proposed site development from a geotechnical viewpoint. In general, our
_ study was to evaluate potential remedial removal depths, develop recommendations for
earthwork construction, and provide geotechnical foundation design parameters. In
addition, as discussed in our referenced report, additional investigations were performed
to assess an area of "collapsible soil" previously identified by LOR Geotechnical Group,
Inc. (LOR, 1994a) on the adjacent property.
EXECUTIVE SUMMARY
Based on our review of data (Appendix A), field exploration, laboratory testing, and
geologic and engineering analyses, the proposed site appears suitable for its intended
use, from a geotechnical viewpoint, provided the recommendations presented in the text
of this report are implemented.
• Portions of the onsite allluvial earth materials display a potential for hydrocollpse as
indicated in previous investigations by LOR Geotechnical Group, Inc. (LOR).
Delineation of this affected area has been provided in this report by GSI.
• Options for remedial earthwork/removals and associated foundation
recommendations are outlined in the conclusions and recommendations section
of this report.
• Our review indicates no known active faults are crossing the site area, and the site
is not within an Alquist-Priolo Earthquake Fault Zone.
• Based on sampling, lab testing, and analysis by GSI, the potential for liquefaction,
subsidence, or mass wasting within the site is considered low.
• Laboratory testing indicates the expansion potential of the onsite soils is low to very
low. Lab data regarding sulfate content and corrosivity were not available at the
time of this report. When this data is available, an addendum to this report will be
— provided.
• Adverse geologic features that would preclude project feasibility were not
encountered.
_ The recommendations presented in this report should be incorporated into the
design and construction considerations of the project.
Torn Ranch Builders, LLC W.O. 2492-A-SC
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GeoSoils, Inc.
_ The opportunity to be of service is sincerely appreciated. If you should have any
questions, please do not hesitate to contact our office.
Respectfully submitted,
Y_ GeoSoils, Inc. g�caVD G��=0 l
P.O.1340
John P. Franklin *' David W. Skelly
Engineering Geologist, CEG j Civil Engineer, RCE 4785 -
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Engineering Geologist, Exp.
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Torn Ranch Builders, LLC W.O. 2492-A-SC
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GeoSoils, Inc.
TABLE OF CONTENTS
SCOPE OF SERVICES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
SITE DESCRIPTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
PROPOSED DEVELOPMENT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
FIELD STUDIES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
GEOLOGY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Regional Geologic Setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Site Earth Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Undocumented Fill (Unmapped) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Colluvium (Unmapped) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Quaternary-age Alluvial Deposits (Map Symbol - Qiv) . . . . . . . . . . . . . . . . . . . . . 4
FAULTING AND REGIONAL SEISMICITY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
GROUNDWATER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
OTHER GEOLOGIC HAZARDS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Liquefaction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
_ Subsidence . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Mass Wasting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
_ LABORATORY AND FIELD TESTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Moisture-Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Laboratory Standard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Expansion Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Corrosion/Acidity Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
-
EMBANKMENT FACTORS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
CONCLUSIONS AND RECOMMENDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Demolition/Grubbing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Treatment of Existing Ground . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Fill Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Slope Considerations and Slope Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
RECOMMENDATIONS - FOUNDATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
_ General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
CONVENTIONAL FOUNDATIONS (Areas not susceptible to hydrocollapse) . . 16
Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Bearing Value . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
GeoSoiils, Inc.
Lateral Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Foundation Settlement - Structural Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Construction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
_ Expansion Index - Very Low to Low (0 to 50) . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Expansion Classification - Medium (El 51 to 90) . . . . . . . . . . . . . . . . . . . . . . . . . 19
_ POST-TENSIONED SLAB DESIGN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
California Foundation Slab Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Post-Tensioning Institute Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
RETAINING WALLS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Restrained Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Cantilevered Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Wall Backfill and Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Footing Excavation Observation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
RECOMMENDATIONS-POST EARTHWORK . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Planting and Landscape Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Erosion Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
_ Additional Site Improvements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Additional Grading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Footing Trench Excavation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Drainage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Tile Flooring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Gutters and Downspouts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Exterior Slabs and Walkways . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
SUPPLEMENTAL MOISTURE CONDITIONING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
TRENCH BACKFILL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
PLAN REVIEW . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
INVESTIGATION LIMITATIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
FIGURES:
Figure 1 - Site Location Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Figure 2 - California Fault Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
_ ATTACHMENTS:
Plate 1 - Geotechnical Map . . . . . . . . . . . . . . . . . . . . . . . . . Rear of Text in Pocket
Appendix A - References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear of Text
Appendix B - Boring Logs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Rear of Text
Appendix C - EQFAULT, EQSEARCH, FRISK89 . . . . . . . . . . . . . . . . . Rear of Text
Appendix D - General Earthwork and Grading Guidelines . . . . . . . . . Rear of Text
Torn Ranch Builders, LLC Table of Contents
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GeoSoiils, Inc.
PRELIMINARY GEOTECHNICAL INVESTIGATION
10-ACRE PARCEL AND A PORTION OF ADJACENT PARCEL
TORN RANCH PROPERTY
CITY OF LAKE ELSINORE, RIVERSIDE COUNTY, CALIFORNIA
SCOPE OF SERVICES
The scope of our services has included the following:
1 . Review of available soils and geologic reports, including aerial photography, for the
site area (Appendix A).
2. Review of the preliminary 40-scale Tentative Tract Maps, prints dated August 28,
1998, by Canty Engineering Group (CEG).
3. Geologic site reconnaissance and mapping.
4. Subsurface exploration consisting of the excavation of 5 borings across the site and
an additional 5 borings within a portion of the adjacent parcel to delineate an area,
previously noted by LOR (1994a), which contained some potential for settlement
due to hydrocollapse (logs of borings are included in Appendix B).
_ 5. Pertinent laboratory testing of representative soil samples collected during our
subsurface exploration program.
6. General areal seismicity evaluation.
7. Appropriate engineering and geologic analysis of data collected.
8. Preparation of this geotechnical report, including boring logs, laboratory test
results, seismic data, general earthwork factors, recommendations for site grading,
and preliminary foundation design.
SITE DESCRIPTION
The subject property primarily consists of approximately 10± acres of previously farmed
walnut orchards, located in the City of Lake Elsinore, Riverside County, California (see Site
Location Map, Figure 1). The site is located north of Washington Avenue, south of Saint
Clair, west of Terra Cotta Road and east of the extension of Pennsylvania Street. An
adjoining portion of the adjacent parcel to the east was also investigated as a part of this
report. Overall, the property is relatively level with a gently sloping gradient to the
_ southeast. Based upon a review of the referenced tentative tract map, elevations within
the site range from 1,356 feet MSL to 1 ,752 feet MSL for a total relief of about 16± feet.
The central portion of the parcel is occupied by residential and barn structures with
associated with past farming operations. Scattered trees and remnant stumps are also
present.
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Base Map: Alquist-Priolo Special Studies Zones, 7.5 minute, Alberhill and Elsinore 06a&angle,
Topographic base. USGS. 1954, photorevised, 1973.
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SITE LOCATION MAP
0 2000 4000
Scale Feet Figure 1
PROPOSED DEVELOPMENT
Based on our review of the tentative tract plan (CEG, 1998), it is our understanding that the
proposed project would consist of residential development (single-family, detached
houses), associated interior roadways, and underground main-line and onsite utility
improvements. Cut and fill grading techniques would be required to bring the site to
design grade. The referenced plans indicate that cuts and fills on the order of less than
5± feet are anticipated.
It is our understanding that the residential dwellings would consist of one- or two-story
structures with continuous footings, utilizing slab-on-grade and masonry block or wood-
frame construction. Building loads are assumed to be typical for this type of relatively light
construction.
FIELD STUDIES
Field investigations conducted during our evaluation of the property for this study
consisted of geologic reconnaissance mapping and excavation of 5 exploratory borings
within the site to evaluate near surface soil and geologic conditions. In addition, 5
additional borings were advanced on the adjacent parcel to the west to explore and
delineate an area previously indicated by LOR (1994a) as being underlain by "collapsible
soil." The borings were logged by a geologist from our firm. Representative bulk and in
place samples were taken for appropriate laboratory testing. Logs of the borings are
presented in B. The approximate locations of the borings are shown on Plate 1.
GEOLOGY
Regional Geologic Setting
The subject property is located within a prominent natural geomorphic province in
southwestern California known as the Peninsular Ranges (Weber, 1977). It is characterized
by steep, elongated mountain ranges and valleys that trend northwestward. 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.
Bedrock in the region has been faulted and fractured by both strike-slip and compressional
northwest-trending faults, which are related to the San Andreas transform-fault system.
Some of these fault zones have remained active to the present time, including the San
Jacinto fault zone, the nearby Elsinore fault zone, and the Newport-Inglewood - Rose
Canyon fault zone. No known active faults (Hart, 1997), or major potentially active faults
are shown on published maps on the site (Jennings, 1994). It should be noted, however,
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that the Glen Ivy North segment of the Elsinore fault zone is denoted as active (i.e.,
Earthquake Fault Zone) northwest of the subject site (Hart, 1997). In addition, the property
lies within the Elsinore-Temecula Trough (Norris, 1990).
Site Earth Materials
Earth materials in the site vicinity are undocumented fill, colluvium (topsoil/slopewash), and
alluvial deposits. The earth materials are generally described below from youngest to
oldest; and their limits, based on the available data, are indicated on Plate 1.
Undocumented Fill (Unmapped)
Minor undocumented fill is present in the area where previous storage tanks had been
removed from the farm house area. It is our understanding that backfill consisted of
imported soils. The maximum depth of these undocumented fill areas is reportedly
— approximately 6± feet. This material is not considered suitable in its present state for the
support of settlement sensitive structures.
Colluvium (Unmapped
Most of the site is mantled by colluvial soils. This material is mostly residual, having
developed through weathering and decomposition of the underlying older alluvial deposits.
Thickness of the colluvium ranges from approximately 2 feet up to 5 feet over the site. The
site colluvium generally consists of dry, light brown, porous silty sand with frequent gravel.
Tree roots and rootlets were common throughout the unit. The colluvium is loose to
medium dense and subject to consolidation. Accordingly, these soils are considered
unsuitable for support of additional fill, improvements, or structures in their existing state.
Quaternary-age Alluvial Deposits (Map Symbol - Qiv)
Grading into and/or underlying the colluvium, relatively older sedimentary alluvial deposits
were encountered underlying the site. These late Pleistocene-age sediments were
deposited as a series of valley flood plain and valley fill deposits (Weber, 1977).
Alluvial deposits encountered vary from fine-to coarse-grained silty sand to sandy clay and
sandy gravel with pebble- to cobble-size slate and quartzite clasts. These materials are
generally light brown and grayish brown to reddish brown in color, loose to medium dense
or hard, and dry to wet. As identified in LOR (1994a), and corroborated by our studies,
zones of this material were encountered at depths varying from 5± to 15± feet which were
loose and possessed at least a moderate potential for collapse under saturated conditions.
The area affected by these low density materials is shown on the enclosed Plate 1 .
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FAULTING AND REGIONAL SEISMICITY
The site is situated in an area of active as well as potentially-active faults. The nearby Glen
Ivy North fault zone is a part of the Elsinore fault zone and is considered active and is
included within an Alquist-Priolo Earthquake Fault Zone. Our review indicates that there
are no known active faults crossing the site within the area proposed for development, and
the site is not within a Fault-Rupture Hazard Zone (Hart, 1997). During our review of aerial
photographs (USDA, 1980), we did not observe photolineaments transecting the site.
The following table lists the major faults and fault zones in southern California that could
have a significant effect on the site should they experience activity.
ABBREVIATED FAULT NAME APPROXIMATE DISTANCE MILES (KM)
Casa Loma (San Jacinto) 22 (36)
Chino 12 (19)
Clamshell-Sawpit 46 (74)
Coronado-A ua Blanca 42 (67)
Cucamonga 34 55
Elsinore 0.6 (1)
Elysian Park Seismic Zone 49 (79)
Glen Helen-Lytle Creek-Claremont(San Jacinto) 23 (36)
Hot Springs-Buck Ridge (San Jacinto) 28 44)
Newport-]ng I ewood-(North) 46 (74
Newport-Inglewood-Offshore 27 (43)
North Frontal Fault Zone 41 (66)
Palos Verdes Hills 42 (68)
Ravmond 48 (78)
Rose Canyon 38 (61)
San Andreas (Mojave) 42 (67)
San Andreas (S. Bernardino Mtns) 34 (54)
San Gorgonio-Banning 25 41)
San Jose 34 (54)
Sierra Madre-San Fernando 36 (57)
Whittier-North Elsinore 17 (28)
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The possibility of ground shaking at the site may be considered similar to the southern
California region as a whole. The relationship of the site location to these major mapped
faults is indicated on the California Fault Map (Figure 2). Our field observations and review
of readily available geologic data indicate that known active faults do not cross the site.
The acceleration-attenuation relations of Campbell and Bozorgnia (1994), Joyner and
_ Boore (1982), and Campbell (1993) have been incorporated into EQFAULT (Blake, 1989).
For this study, peak horizontal ground accelerations anticipated at the site were
determined based on the random mean plus 1 - sigma attenuation curve and mean
attenuation curve developed by those authors. EQFAULT is a computer program by
Thomas F. Blake (1989), 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 "maximum credible" and "maximum probable" earthquakes on
that fault. Site acceleration (g) is computed by any of the 19 user-selected acceleration-
attenuation relations that are contained in EQFAULT. Computer printouts of the EQFAULT
program are included in Appendix C. Based on the above, peak horizontal ground
accelerations from an upper bound (maximum credible) event may be on the order of
0.51 g to 1.3g, and a maximum probable event may be on the order of 0.44g to 1.0g.
-
Historical site seismicity was evaluated with the acceleration-attenuation relations of
Campbell (1993) and the computer program EQSEARCH (Blake, 1989, updated to 1998).
This program performs a search of historical earthquake records for magnitude 5.0 to 9.0
seismic events within a 100 mile radius, between the years 1800 to 1998. Based on the
selected acceleration-attenuation relationship, a peak horizontal ground acceleration is
estimated, which may have effected the site during the specific event listed. Based on the
available data and the attenuation relationship used, the estimated maximum (peak) site
acceleration during the period 1800 to 1997 was 0.59g. In addition,site specific probability
of exceeding various peak horizontal ground accelerations and a seismic recurrence curve
are also estimated/generated from the historical data. Computer printouts of the
EQSEARCH program are included in Appendix C.
A probabilistic seismic hazards analysis was performed using FRISK89 (Blake, 1988) which
models earthquake sources as lines and evaluates the site specific probabilities. Based
on a review of these data, and considering the relative seismic activity of the southern
California region, a repeatable horizontal ground acceleration of 0.26g was calculated.
This value was chosen as it corresponds to a 10 percent probability of exceedance in 50
years (or a 475 year return period). Computer printouts of the FRISK89 program are
included in Appendix C.
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0 50 100
SCALE
\ (Miles)
SAN FrRANCISCO
d
L GELES
SITE LOCATION (+):
--
Latitude — 33.6883 N
Longitude — i 17.3822 W
Torn Ranch
CALIFORNIA 1FAULT
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GROUNDWATER
Seeps, springs, or other indications of a high groundwater level were not noted on the
_ subject property during the time of our field investigation. Surface features commonly
associated with water wells were not observed onsite during our site reconnaissance;
however, based upon information provided by Mr. Ralph Torn, an old water well
constructed in 1928/1929 was abandoned under the existing shop shed. Historical data
reviewed at the Riverside County Flood Control District offices indicated numerous water
well locations in the site vicinity. Historical water levels from 1933 to 1981 indicate depth
to water in the area ranged from roughly 130 feet to 345 feet. Data provided in a
geotechnical report on the site (LOR, 1994b) indicate that groundwater depths in a well
situated east of the current farm were reported varying from 189 to 344 feet.
"Perched" groundwater, where relatively impermeable fill and/or sediments underlie
relatively permeable fill and/or sediments filled with water may be encountered at shallower
depths onsite, especially during the rainy season. Based upon our review of available
data, the overall regional groundwater gradient is estimated to be in a southeasterly
direction toward Lake Elsinore. Onsite gradients, however, may be regionally affected by
the Elsinore fault zone.
OTHER GEOLOGIC HAZARDS
Liquefaction
Seismically-induced liquefaction is a phenomenon in which cyclic stresses, produced by
earthquake-induced ground motion, create excess pore pressures in soils. The soils may
thereby acquire a high degree of mobility, and lead to lateral movement, sliding, sand
boils, consolidation and settlement of loose sediments, and other damaging deformations.
This phenomenon occurs only below the water table; but after liquefaction has developed,
it can propagate upward into overlying, non-saturated soil as excess pore water dissipates.
Typically, liquefaction has a relatively low potential at depths greater than 45 feet and is
virtually unknown below a depth of 60 feet.
Liquefaction susceptibility is related to numerous factors and the following conditions
should be present for liquefaction to occur: 1) sediments must be relatively young in age
and not have developed a large amount of cementation: 2) sediments generally consist
_ of medium to fine grained relatively cohesionless sands; 3) the sediments must have low
relative density; 4) free groundwater must be present in the sediment; and 5) the site must
experience a seismic event of a sufficient duration and magnitude, to induce straining of
_ soil particles.
The condition of liquefaction has two principal effects. One is the consolidation of loose
sediments with resultant settlement of the ground surface. The other effect is lateral
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sliding. Significant permanent lateral movement generally occurs only when there is
significant differential loading, such as fill or natural ground slopes. No such loading
conditions exist on the site. In the site area, we found there is a potential for seismic
_ activity. However, a high groundwater table (30 to 50 feet below the ground surface) does
not exist and the older alluvial sediments were silty, fine to coarse grained, massively
bedded and become dense with depth.
Inasmuch as three or four of these five conditions discussed above do not have the
potential to affect the site our evaluation indicates that the potential for liquefaction and
associated adverse effects within the site is very low, even with a future rise in groundwater
levels. The site conditions will also be improved by removal and recompaction of low
density near-surface soils. Therefore, it is our opinion that the liquefaction potential does
not constitute a significant risk to site development.
Subsidence
Our review of readily available data did not indicate that the site area is subsiding due to
_ down-faulting along bordering fault zones, groundwater withdrawal, or hydrocompaction.
The scope of this potential for affecting the subject site is beyond the scope of this current
study; however, aerial subsidence in the site area cannot be totally precluded. It should
_ not be any greater at the site than for adjacent and existing already developed properties.
However, ground subsidence is expected to occur over the site due to equipment working
(vibrations) and the effect of loading of additional fill (weight). Again, both factors are
variable and difficult to estimate.
Ground subsidence (consolidation) due to vibrations would depend upon the equipment
being used, and the dynamic effects of the equipment. Most of these factors cannot be
determined at this time and may be beyond ordinary estimating possibilities.
Our evaluation indicates that ground subsidence due to vibration/loading, may be on the
order of 0.15-0.2 feet. In general, field subsidence should depend upon equipment, haul
routes, duration of grading, and the effect of dynamic loading.
Mass Wasting
Mass wasting refers to the various processes by which earth materials are moved down
slope in response to the force of gravity. Examples of these processes include slope
creep, surficial failures, and deep-seated landslides. Creep is the slowest form of mass
wasting and generally involves the outer 5 to 10 feet of the slope surface. During heavy
rains, such as those in 1969, 1978, and 1980, 1983, 1993, and 1998 creep-affected
materials may become saturated, resulting in a more rapid form of down slope movement
(i.e., landslides and/or surficial failures). The subject site consists of relatively low gradient
terrain and indications of mass wasting phenomena on the site were not observed during
our review of stereoscopic photographs of the area (USDA, 1980) or during our site
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reconnaissance. Therefore, the potential for mass wasting phenomena to affect the site
is considered low. Likewise,the potential for seismically induced landsliding is considered
low. The hazard from flooding should be evaluated by the project civil engineer.
LABORATORY AND FIELD TESTING
Classification
Soils were classified visually according to the Unified Soils Classification System and by
supplemental index testing. The soil classifications are shown on the boring logs,
Appendix B.
Moisture-Density
The field moisture content and dry unit weight were determined in the field using the sand
cone and nuclear- densometer methods ASTM 1556, ASTM D-2922, and D-3017. The dry
unit weight was determined in pounds per cubic foot, and the field moisture content was
determined as a percentage of the dry weight. The results of these tests are shown on the
log of test pits, Appendix B.
Laboratory Standard
The maximum dry density and optimum moisture content was determined for the major soil
type encountered in the trenches. The laboratory standard used was ASTM D-1557. The
moisture-density relationship obtained for this soil is shown below:
BORING DI MAXIMUM DRY OPTIMUM MOISTURE
- SOIL TYPE. fts DENSITY o CONTENT 'fa
Silty SAND, light brown B-4 @ T 129.0 9.5
Silty SAND, reddish brown B-6 @ 5' 131.0 9.0
11 Silty SAND, dark brown B-10 @ 7' 127.5 1 11.5
Expansion Testing
Expansion index testing was performed on a representative soil sample, in accordance
with UBC Standard No. 18-2 of the Uniform Building Code. An expansion index of 0 was
determined for the sample and is classified as having very low to low expansion potential.
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Based on our observation of site soils, the potential for soils to locally exhibit a medium
expansive potential exists.
Corrosion/Acidity Testing
A typical sample of the site material was analyzed for corrosion/acidity potential. The
testing included determination of pH, soluble sulfates, saturated resistivity, redox potential,
and alkalinity. At the time of this report the results were not available. An addendum to
this report will be issued when the testing is completed.
EMBANKMENT FACTORS
Embankment factors (shrinkage)for the site have been estimated based upon our field and
laboratory testing, visual site observations, and experience. It is apparent that shrinkage
would vary with depth and with areal extent over the site, based on previous site use.
Variables include vegetation, weed control, and discing. However, all these factors are
difficult to define in a three-dimensional fashion.
Therefore, the information presented below represents average shrinkage/bulking values,
using certain earthwork assumptions as follows:
Range of maximum density = 127.0 to 131.0 pcf
Relative Compaction = 92%
Material % Range
Colluvial Deposits (upper 2 ft) 15 to 20 (shrinkage)
Colluvial Deposits (2 ft to 5 ft) 7 to 10 (shrinkage)
_ Alluvial Deposits (2 ft to 10 ft) 7 to 10 (shrinkage)
Alluvial Deposits (10 ft to 15 ft) 9 to 13 (shrinkage)
An additional shrinkage factor item would include the removal of individual large plants or
trees. The root structures/root balls of these plants and trees vary in size; but when pulled,
_ they may result in a loss of 1/2 to 11/2 cubic yards of volume. This factor needs to be
multiplied by the number of significant plants or trees present to determine the net loss.
Considering the former use of the property as a tree/nut farm, this net shrinkage from
remaining tree roots/stumps may be a significant factor.
The above factors indicate that earthwork balance of the site would be difficult to define
and flexibility in design is essential to achieve a balanced end product.
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CONCLUSIONS AND RECOMMENDATIONS
General
Based on our field exploration and laboratory testing, it is GSI's opinion that the project is
suited for the proposed use from a soil engineering and geologic viewpoint. The primary
geotechnical concerns anticipated to impact site development are the depths and limits
of remedial earthwork (i.e., removals) of onsite earth materials. The recommendations
presented below should be incorporated in the design, grading, and construction
considerations.
1. Soil engineering, observation, and testing services.should be provided during
grading to aid the contractor in removing unsuitable soils and in his effort to
compact the fill.
2. In general and based upon the available data, groundwater is not expected to be
a factor in development of the site.
3. Due to the nature of the onsite materials, caving and sloughing should be
anticipated to be a factor in all subsurface excavations and trenching. General
_ Earthwork and Grading Guidelines are provided at the end of this report as
Appendix D. Specific recommendations are provided below.
_ 4. Some oversize materials and associated excavation and placement difficulty may
be anticipated during grading and utility trenching.
Demolition/Grubbing
1 . Existing structures, vegetation (i.e., citrus trees and root structures), and any
miscellaneous debris should be removed from the areas of proposed grading.
2. Any previous foundations, irrigation lines, cesspools, septic tanks, leach fields, or
other subsurface structures uncovered during the recommended removal should
be observed by GSI so that appropriate remedial recommendations can be
provided.
3. Cavities or loose soils (including backfilled storage tank pits) remaining after
demolition and site clearance should be cleaned out and observed by the soil
engineer. The cavities should be replaced with fill materials that have been
moisture conditioned to at least optimum moisture content and compacted to at
least 90 percent of the laboratory standard.
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Treatment of Existing Ground
Any existing undocumented fill (i.e., the tank backfill in the farm house area) encountered
should be removed and recompacted. In general, all colluvial deposits should be removed
and replaced with compacted fill.
Previous investigations by LOR (1994a) identified a general area of "collapsible soil" on
immediately adjacent property (part of the Torn Ranch project). Based upon their
analyses, recommendations for deep removals (from 5 to 15 feet) were provided. The
specific area affected was to be outlined on the figure contained in their report. No such
area was noted on their plan during our review. In order to verify the presence of such
"collapsible soil," GSI placed additional borings in the area in conjunction with our
preliminary investigation for the subject 10-acre parcel.
As indicated in GSI (1998), low density soils were identified in GSI's borings within both
parcels. The enclosed Plate 1 indicates the locations of borings (both LOR and GSI) and
outlines the area affected/underlain by those soil materials.
As a result of our laboratory testing and engineering analyses, the following options for
remedial earthwork and foundation design are provided.
Option 1. Overexcavation/removal, as previously recommended by LOR (1994a), to a
depth of approximately 15± feet in depth below existing grades, across the
area indicated on Figure 1 may be performed. Following this procedure,
conventional footings could be utilized for residential construction.
Option 2. Overexcavation/removal of the upper 5± feet of native soils, below existing
grades,followed by flooding/saturation of an additional 10± feet of the native
materials (This could require a few weeks or more to reach saturation).
Verification of a minimum 85% saturation would be required via test pits and
field moisture content testing at the 15 foot level. Following moisture
verification, compaction of the removal bottom would require a vibratorX
sheeps-foot to aid in the inducement of hydrocollapse in the underlying
materials. Following this procedure, conventional footings could be utilized
for residential construction.
Option 3. Overexcavation/removal of the upper 5± feet of native soils, below existing
grades, followed by flooding/saturation of an additional 3± feet of the native
soils. Verification of a minimum 85% saturation would be required via test
pits and field moisture content testing. Following moisture verification, _
compaction of the removal bottom would require a vibratory sheeps-foot to
aid in the inducement of hydrocollapse in the underlying materials. Post-
tensioned foundation designs, which accommodate 1.85 inches of
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differential settlement and an angular distortion of 1/260 for a 40-foot span,
could be utilized for residential structures in this area.
Remedial recommendations (LOR, 1994a) for the remainder of the Torn Ranch property
were for removals of approximately 2± feet, with actual removal depths to be verified in the
field during earthwork construction. Due to the variable nature of the onsite native
materials, GSI would recommend that following these removals additional
flooding/saturation of the removal bottom to a depth of 3± additional feet be performed.
Verification of a minimum 85% saturation would be required via test pits and field moisture
content testing. Conventional or post-tension design foundation systems may then be
utilized.
In proposed fill areas and subsequent to all removals, the upper 12 inches of the
underlying alluvial deposits should be scarified and compacted to a minimum relative
compaction of 90 percent of the laboratory standard. The moisture content of prepared
surfaces should be evaluated by the geotechnical consultant prior to any fill placement.
The upper 36 inches of finish grade materials on fill pads should consist of 12-inch and
minus earth materials.
In proposed cut areas which do not attain the appropriate recommended removal depth
per plan, additional removals/overexcavation to the specified removal depth would be
necessary. In proposed cut areas which exceed the recommended removal depth, the
exposed materials would need to be moisture condition and compacted to 90 percent
relative compaction.
Any existing undocumented fill and removed natural ground materials may be reused as
compacted fill provided that major concentrations of vegetation and miscellaneous debris
and oversize materials (larger than 12 inches) are removed prior to or during fill placement.
Localized deeper removals may be necessary due to buried drainage channel meanders
or dry porous materials. The project soils engineer/geologist should determine the depth
of the potentially compressible materials within the proposed fill areas that will need to be
removed, based on the exposed conditions during grading.
Cut portions of any fill-over-cut slopes should be excavated first, so that an evaluation of
the suitability of the cut portions for its intended use can be made by the geotechnical
consultant.
While remedial earthwork will, in some areas, accommodate/eliminate any planned cut/fill
transitions, in order to achieve a more uniform pad subgrade, cut portions of any remaining
transition building pad should be overexcavated to a depth of 3 feet for a minimum
distance of 5 feet horizontally outside the perimeter footing of the structures, and replaced
with compacted fill. This should be performed in areas proposed for settlement-sensitive
improvements. In general, all building pads should maintain a minimum of 3 feet of
compacted fill.
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Fill thickness greater than 9 feet below any proposed residential pads should not exceed
a 1:3 (minimum:maximum) ratio. Where such conditions exist following removals,
additional laying back of sloping surfaces to a 3:1 (horizontal:vertical) inclination will be
required.
Fill Placement
1. Fill materials should be brought to at least optimum moisture content, 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 be placed
under the recommendations and supervision of the soils engineer and/or removed
from the site. General recommendations for placement of oversize materials are
contained in Appendix D (Grading Guidelines).
4. Any import materials should be observed and determined suitable by the soils
engineer pfLor 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.
5. An effort should be made to keep any expansive soils lower than 3 feet from the
finish grade.
Slope Considerations and Slope Design
A detailed evaluation of slope stability is beyond the scope of this report. However, a
general discussion of slope stability is included herein. Base on our experience on similar,
nearby projects, proposed cut and fill slopes constructed using onsite materials, to the
heights proposed, should be grossly and surficially stable provided the recommendations
contained herein are implemented during site development. All slopes should be
designed and constructed in accordance with the minimum requirements of the City of
_ Lake Elsinore,the Uniform Building Code (UBC),the recommendations in Appendix D, and
the following:
1. Fill slopes should be designed at 2:1 (horizontal to vertical) gradients and should
not exceed 15 feet in height. Fill slopes should be properly built and compacted.
Guidelines for slope construction are presented in Appendix D.
2. Cut slopes in native materials should be at gradients of 2:1 or flatter and should not
exceed 15 feet in height. Due to the presence of loose sands and gravels within
portions of the alluvial deposits, remedial measures such as stabilization of slopes
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_ and or laying back of slopes to the angle of repose may be necessary. Although
not anticipated, this would best be determined based on field conditions exposed
during actual earthwork.
3. Cut and fill slopes should be provided with appropriate surface drainage features
and landscaped (with drought-tolerant vegetation) as soon as possible after grading
to minimize any potential for erosion. Berms should be provided at the top of fill
slopes, and brow ditches should be constructed at the top of cut slopes. Lot
drainage should be directed such that surface runoff on slope faces is not
permitted.
RECOMMENDATIONS - FOUNDATIONS
General
The foundation design and construction recommendations are based on laboratory testing
_ and engineering analysis of onsite earth materials by GSI. Recommendations for
conventional foundation systems as well as post-tension designs are provided in the
following sections. The foundation systems may be used to support the proposed
structures, provided they are founded in competent bearing material. The proposed
foundation systems should be designed and constructed in accordance with the guidelines
contained in the Uniform Building Code (1997).
The information and recommendations presented in this section are not meant to
supersede design by the project structural engineer or civil engineer specializing in
structural design. Upon request, GSI could provide additional input/consultation
regarding soil parameters, as related to foundation design.
Both conventional and post-tensioned designs are recommended for different remedial
grading options presented earlier in this report. If Options 1 or 2 are implemented,
conventional foundations may be utilized. Conventional foundation systems may also be
utilized for those areas outside of the area of "collapsible soil" indicated on Plate 1. If
Option 3 is implemented, post-tension foundation systems are recommended for structures
which are to be founded in the "collapsible soil" area indicated on plate 1. Design and
construction criteria for both types of foundation systems are presented below.
CONVENTIONAL FOUNDATIONS (Areas not susceptible to hydrocollapse)
Design
Our field work and laboratory testing indicates that onsite soils are generally very low to
low in expansion potential. Due to the possible presence of medium expansive soils
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onsite, recommendations for medium expansive soils are also provided.
Recommendations for foundation design and construction are presented below based on
these data. The foundation system should be designed and constructed in accordance
_ with the guidelines contained in the Uniform Building Code (1997).
Bearing Value:
1 . Conventional spread and continuous strip footings may be used to support the
proposed structures, provided they are founded entirely in properly compacted fill
or competent formational material.
2. An allowable bearing value of 1500 pounds per square foot should be used for
design of continuous footings 12 inches wide and 12 inches deep and for design
of isolated pad footings 24 inches square and 12 inches deep entirely into
compacted fill or competent formational material. This value may be increased by
250 pounds per square foot for each additional 12 inches in depth to a maximum
value of 2000 pounds per square foot. The above values may be increased by
_ one-third when considering short duration seismic or wind loads. No increase, in
bearing, for footing width is recommended.
Lateral Pressure:
1 . Passive earth pressure may be computed as an equivalent fluid having a density of
250 pounds per cubic foot per foot of depth, to a maximum earth pressure of 2000
pounds per square foot.
2. An allowable coefficient of friction between soil and concrete of 0.30 may be used
with the dead load forces.
3. When combining passive pressure and frictional resistance, the passive pressure
component should be reduced by one-third.
4. All footings should maintain a minimum 7 foot horizontal set back from the base of
the footing to any descending slope. Footings for structures adjacent to retaining
_ walls should be deepened so as to extend below a 1:1 projection upward from the
bottom inside edge of the wall stem. Alternately, walls may be designed to
accommodate structural loads from buildings or appurtenances as described in
retaining wall section of this report.
Foundation Settlement - Structural Loads (Areas not susceptible to hydrocollapse)
Provided that the recommendations contained in this report are incorporated into final
design and construction phase of development, a majority (greater than 75 percent) of the
anticipated foundation settlement is expected to occur during construction. Maximum
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settlement is not expected to exceed approximately '/2 to 1 inch and should occur below
the heaviest loaded columns. Differential settlement of structures underlain by properly
compacted fill is not anticipated to exceed '/2 inch between similar elements, in a 30-foot
_ span.
Construction
The following foundation construction recommendations are presented as a minimum
criteria from a soils engineering viewpoint and assume that the soils in the top 3 feet of
finish grade would have a very low to low to medium expansion potential.
Recommendations by the project's design-structural engineer or architect, which exceeds
the soils engineers' recommendations, should take precedence over the following
minimum requirements. Final foundation design should be provided based on the
expansion potential of the near surface soils encountered during grading.
Expansion Index - Very Low to Low (0 to 501
_ 1 . Continuous exterior footings should be founded at a minimum depth of 12 inches
below the lowest adjacent ground surface for one-story structural loads, and a
minimum depth of 18 inches below the lowest adjacent ground surface for two-story
structural loads, in accordance with the minimum requirements of the latest edition
of the UBC. The structural engineer should review and approve these
recommendations. Continuous interior footings may be founded at a minimum
depth of 12 inches below the lowest adjacent ground surface. Footings should be
a minimum of 12 inches wide or as determined by the structural engineer.
— 2. All continuous footings should have one No. 4 reinforcing bar placed at the top and
one No. 4 reinforcing bar placed at the bottom of each footing from a geotechnical
standpoint. Pad footings should be reinforced per structural requirements.
3. Where moisture condensation is undesirable, concrete slabs should be underlain
with a vapor barrier consisting of a minimum six-mil polyvinyl chloride or equivalent
membrane, with all laps sealed. This membrane could be placed on native earth
materials and a minimum 2-inch layer of sand should be placed over the visqueen,
to aid in uniform curing of the concrete.
4. Column footings should be founded at a minimum depth of 18 inches. If expansive
soils are present in the top 3 feet of finish grade, column footings should not be
used or should be made continuous, by means of reinforced grade beam(s).
S. A grade beam reinforced as above and at least 12 inches by 12 inches should be
provided across the garage entrances. The base of the grade beam should be at
the same elevation as the adjoining footings.
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6. A minimum slab thickness of 4 inches is recommended. The design engineer
should determine the actual thickness of concrete slabs based upon proposed
loading and use. Garage slabs should be poured independent of the perimeter
footings and separated from the stem wall by means of joint material to permit
relative movement. Consideration should be given to the placement of a visqueen
vapor barrier beneath garage slabs.
7. Concrete slabs should be minimally reinforced with 6-inch, No. 10 by No. 10 (6 x 6-
W1 .4 x W1.4), welded-wire mesh or equivalent cross-sectional area (No. 3 rebar at
18 inches on center each way). All slab reinforcement should be supported to
ensure proper positioning at mid-height in the slab during placement of the
concrete.
8. Presaturation is not necessary for these soil conditions; however, the moisture
content of the subgrade soils should be equal to or greater than optimum moisture
to a depth of 12 inches below the adjacent ground grade in the slab areas, and
verified by this office within 72 hours of the vapor barrier placement.
Expansion Classification - Medium (EI 51 to 90)
1 . Conventional continuous footings should be founded at a minimum depth of 18
inches below the lowest adjacent ground surface for one- or two-story structural
loads. Interior footings may be founded at a depth of 12 inches below the lowest
adjacent ground surface.
Footings for one-story structural loads should have a minimum width of 12 inches,
and footings for two-story structural loads should have a minimum width of 15
inches. All footings should be reinforced with a minimum of two No. 4 reinforcing
bars at the top and two No. 4 reinforcing bars at the bottom. Isolated interior and/or
exterior piers and columns are not recommended.
2. A grade beam, reinforced as above, and at least 12 inches square, should be
provided across the garage entrances. The base of the reinforced grade beam
should be at the same elevation as the adjoining footings.
3. Concrete slabs in residential areas and areas with moisture sensitive flooring should
be underlain by a total of 4 inches of sand. In addition, a vapor barrier consisting
of a minimum of 8-mil, polyvinyl-chloride membrane, with all laps sealed should be
provided. Two inches of the sand base should be placed over the membrane to aid
in uniform curing of the concrete.
4. Concrete slabs, including garage areas, should be reinforced with No. 4
reinforcement bars placed on 18-inch centers, in two horizontally perpendicular
directions (i.e., long axis and short axis). All slab reinforcement should be
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supported to ensure proper mid-slab height positioning during placement of the
concrete. "Hooking" of reinforcement is not an acceptable method of positioning.
_ 5. Garage slabs should be poured separately from the residence footings and be
quartered with expansion joints or saw cuts. A positive separation from the footings
should be maintained with expansion joint material to permit relative movement.
6. The residential and garage slabs should have a nominal thickness of 4 inches, and
the slab subgrade should be free of loose and uncompacted material prior to
placing concrete.
7. Presaturation of slab areas is recommended for these soil conditions. The moisture
content of each slab area should be 120 percent or greater above optimum and
verified by the soil engineer to a depth of 18 inches below adjacent ground grade
in the slab areas, within 48 hours of the vapor barrier placement.
8. As an alternative, an engineered post-tension foundation system may be used.
Engineering parameters for post-tension design can be provided upon request.
9. Soils generated from footing excavations to be used onsite should be compacted
to a minimum relative compaction 90 percent of the laboratory standard, whether
it is to be placed inside the foundation perimeter or in the yard/right-of-way areas.
This material must not alter positive drainage patterns that direct drainage away
from the structural areas and toward the street.
POST-TENSIONED SLAB DESIGN
The post-tensioned slabs should be designed in accordance with the recommendations
— of the California Foundation Slab Method or Post-Tensioning Institute Method. The slabs
should be designed for at least 1 .85 inches of surficial differential settlement (i.e., at least
1 .85 inch in a 40-foot span) for low expansion soils. Based on review of laboratory data
for the onsite materials, the average soil modulus subgrade reaction K, to be used for
design, is 100 pounds per cubic inch. This is equivalent to a surface bearing value of
1 ,000 pounds per square foot.
California Foundation Slab Method
It is recommended that slabs be designed for a free span of 10 feet for low expansion
index (EI) soil. From a soil expansion/shrin_kage standpoint, a fairly common contributing
factor to distress of structures using post-tensioned slabs is a significant fluctuation in the
moisture content of soils underlying the perimeter of the slab, compared to the center,
causing a "dishing" or "arching" of the slabs. To mitigate this possible phenomenon, a
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combination of soil presaturation and construction of a perimeter cut-off wall grade beam
should be employed.
All slab foundation areas should be moisture-conditioned to at least optimum moisture, but
no more than 6 percent above optimum moisture, for a depth of at least 12 inches below
subgrade. A continuous perimeter curtain wall should extend to at least a depth of 12
— inches below exterior grade for low expansion soils. The cut-off walls may be integrated
into the slab design or independent of the slab and should be a maximum of 6 inches. A
visqueen vapor barrier should be placed underneath the slab sandwiched between two
2-inch layers of sand. This vapor barrier should be sealed adequately to provide a
continuous waterproof barrier under the entire slab. Other applicable recommendations
presented under conventional foundations should be adhered to during the design and
construction of the project.
Post-Tensioning Institute Method
Post-tensioned slabs should have sufficient stiffness to resist excessive bending due to
non-uniform swell and shrinkage of subgrade soils. The differential movement can occur
at the corner, edge, or center of slab. The potential for differential uplift can be evaluated
using the 1997 Uniform Building Code Section 1816, based on design specifications of the
Post-Tensioning Institute. The following table presents suggested minimum coefficients
to be used in the Post-Tensioning Institute design method.
Thornthwaite Moisture Index -20 inches/year
Correction Factor for Irrigation 20 inches/year
Depth to Constant Soil Suction 5 feet
Constant soil Suction ( f) 3.6
The coefficients are considered minimums and may not be adequate to represent worst
case conditions such as adverse drainage and/or improper landscaping and maintenance.
_ The above parameters are applicable provided structures have gutters and downspouts
and positive drainage is maintained away from structures. Therefore, it is important that
information regarding drainage, site maintenance, settlements, and effects of expansive
soils be passed on to future owners.
Based on the above parameters, the following values were obtained from figures or tables
of the 1997 Uniform Building Code Section 1816. The values may not be appropriate to
account for possible differential settlement of the slab due to other factors. If a stiffer slab
is desired, higher values of ym may be warranted.
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_ EXPANSION VERY LOW TO MEDIUM
INDEX OF SOIL LOW EXPANSION EXPANSION
SUBGRADE POTENTIAL POTENTIAL
(per UBC) (El = 0-50 (El =51-90)
em center lift 5.0 feet 5.5 feet
em edge lift 2.5 feet 2.7 feet
Ym center lift 1.10 inches 2.0 inches
Ym edge lift 0.35 inch 0.5 inch
_ Deepened footings/edges around the slab perimeter must be used to minimize non-
uniform surface moisture migration (from an outside source) beneath the slab. An edge
depth of 12 inches should be considered a minimum. The bottom of the deepened
footing/edge should be designed to resist tension, using cable or reinforcement per the
structural engineer. Other applicable recommendations presented under conventional
foundation and the California Foundation Slab Method should be adhered to during the
design and construction phase of the project.
RETAINING WALLS
General
The design parameters provided below assume that very low to low expansive soils (Such
as Class 2 permeable filter material or Class 3 aggregate base) are used to backfill any
retaining walls. If high to very highly expansive soils are used to backfill the proposed
walls, increased active and at-rest earth pressures will need to be utilized for retaining wall
design, and may be provided upon request. Building walls, below grade, should be water-
proofed or damp-proofed, depending on the degree of moisture protection desired. The
foundation system for the proposed retaining walls should be designed in accordance with
_ the recommendations presented in the preceding sections of this report, as appropriate.
Footings should be embedded a minimum of 12 inches below adjacent grade (excluding
landscape layer, 6 inches). There should be no increase in bearing for footing width.
Foundations near the tops of slopes should be deepened to conform to the 1997 edition
of the UBC and provide a minimum of 7 feet horizontal distance from the slope face. Rigid
block wall designs located along the top of slope should be reviewed by a soils engineer.
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
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pressure (EFP) of 65 pounds per cubic foot (pcf), plus any applicable surcharge loading.
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.
Cantilevered Walls
_ The recommendations presented below 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 equivalent fluid pressure approach may
be used to compute the horizontal pressure against the wall. Appropriate fluid unit weights
are given below for specific slope gradients of the retained material. Values presented
assume low expansive backfill materials. These do not include other superimposed
— loading conditions such as traffic, structures, hydrostatic pressures, seismic events or
adverse geologic conditions. When wall configurations are finalized, the appropriate
loading conditions for superimposed loads can be provided upon request.
_ Surface Slope of Equivalent
Retained Material Fluid Weight
Horizontal to Vertical P.C.F.
Level* 30
2 to 1 43
* Level backfill behind a retaining wall is
defined as compacted earth materials,
properly drained, without a slope for a
_ distance of 2H behind the wall, where H is
the height of the wall.
Wall Backfill and Drainage
The above criteria assumes that very low expansive soils are used as backfill, and that
hydrostatic pressures are not allowed to build up behind the wall. Positive drainage must
be provided behind all retaining walls in the form of perforated pipe placed within gravel
— wrapped in geofabric and outlets. A backdrain system is considered necessary for
retaining walls that are 2 feet or greater in height. Backdrains should consist of a 4-inch
diameter perforated PVC or ABS pipe encased in either Class 2 permeable filter material
or '/z- to 3/4-inch gravel wrapped in approved filter fabric (Mirafi 140 or equivalent). The filter
material should extend a minimum of one horizontal foot behind the base of the walls and
upward at least one foot. Outlets should consist of a 4-inch diameter solid PVC or ABS
— pipe spaced no more greater than 100± feet apart. The use of weep holes in walls higher
than 2 feet should not be considered. The surface of the backfill should be sealed by
pavement or the top 18 inches compacted with relatively impermeable soil. Proper surface
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drainage should also be provided. Consideration should be given to applying a water-
proof membrane to all retaining structures. The use of a waterstop should be considered
for all concrete and masonry joints.
Footing Excavation Observation
_ All footing excavations for walls and appurtenant structures should be observed by the
geotechnical consultant to evaluate the anticipated near surface conditions prior to the
placement of steel or concrete. Based on the conditions encountered during the
observations of the footing excavation, supplemental recommendations may be offered,
as appropriate.
RECOMMENDATIONS-POST EARTHWORK
Planting and Landscape Maintenance
Graded slopes constructed within and/or exhibiting or exposing weathered older alluvial
materials or compacted fill materials derived from alluvial materials may be considered
erosive. Eroded debris may be minimized and surficial slope stability enhanced by
_ establishing and maintaining a suitable vegetation cover soon after construction. Plants
selected by the project landscape architect should be light weight, deep-rooted types that
require little water and are capable of surviving the prevailing climate. Jute-type matting
or other fibrous covers may aid in allowing the establishment of a sparse plant cover.
Water can weaken the inherent strength of all earth materials. Positive surface drainage
away from graded slopes should be maintained and only the amount of water necessary
to sustain plant life should be provided for planted slopes. Overwatering should be
avoided as overwatering the landscape area could adversely affect the proposed site
— improvements. Planting of shrubs or trees adjacent to foundations is not recommended.
Erosion Control
Slopes will be subject to surficial erosion during and after grading. Onsite earth materials
have a moderate to high erosive potential. Evaluation of cuts during grading will be
necessary in order to identify any areas of loose or non-cohesive materials. Should any
significant zones be encountered during earthwork construction, remedial grading (e.g.,
stabilization fills) may be recommended; however, no remedial measures are anticipated
— at this time. Consideration should be given to providing hay bales and silt fences for the
control of surface water during grading.
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Additional Site Improvements
Recommendations for exterior swimming pool design and construction in light of the
presence of varying thickness of fills, can be provided upon request, after site earthwork
is complete. If; in the future, any additional improvements are planned for the site in
general or individual lots, consultation and recommendations concerning the geological
or geotechnical aspects of design and construction of said improvements may be provided
upon request by the client.
— Additional Grading
This office should be notified in advance of any fill placement, supplemental regrading of
the site, or trench backfilling after rough grading has been compacted. This includes
completion of grading in the street and parking areas and utility trench and retaining wall
backfills.
Footing Trench Excavation
All footing trench excavations should be observed by a representative of this office prior
to placing reinforcement. Footing trench spoil and any excess soils generated from utility
trench excavations should be moisture conditioned and properly compacted if not
removed from the site. If excavations become inundated during significant rainstorms,
footing trenches should be observed by the geotechnical consultant for mitigation, if
necessary.
Drainage
Positive site drainage within lots and common areas should be maintained at all times.
Drainage should not flow uncontrolled down any descending slope. Water should be
— directed away from foundations for a distance of 3 to 5 feet, and not allowed to pond
and/or seep into the ground. Roof drainage should be tight lined and directed to a suitable
outlet. Pad drainage should be directed toward the street or other approved area. Due
to the potential for sandy lenses conducive to transmitting water, combined with the
possible hardness and low anticipated permeability of the portions of the fill, local areas
of seepage may develop due to surface sources of irrigation or heavy rainfall. Minimizing
irrigation will lessen this potential. If areas of seepage develop, remedial recommendations
for minimizing this effect could be provided upon request. The use of fertilizers may
change the chemistry of the soils or runoff water and alter the performance of piping,
foundations, and subgrade structures.
Tile Flooring
Tile flooring can crack, reflecting cracks in the concrete slab below the tile, although small
— cracks in a conventional slab may not be significant. Therefore, the designer should
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consider additional steel reinforcement of concrete slabs-on-grade where tile will be
placed. The the installer should consider installation methods that reduce possible
cracking of the the such as slipsheets. Slipsheets or a vinyl crack isolation membrane
(approved by the Tile Council of America/Ceramic Tile Institute) are recommended
between tile and concrete slabs on grade.
Gutters and Downspouts
As previously discussed in the drainage section, the installation of gutters and downspouts
should be considered to collect roof water that may otherwise infiltrate the soils adjacent
to the structures. The downspouts should be drained into PVC collector pipes or non-
erosive devises that will carry the water away from the house. Downspouts and gutters are
not a requirement, however,from a geotechnical viewpoint, provided that positive drainage
is incorporated into project design (as discussed previously).
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 No. 3 rebar placed at 18 inches on center in two
_ horizontally perpendicular directions (long axis and short axis), or 6x6-10/10 welded wire
mesh. 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 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 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.
Shrinkage cracks 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 climate and time
of year, sulfate content of soils, corrosion potential of soils, and fertilizers used on site.
SUPPLEMENTAL MOISTURE CONDITIONING
For very low to low expansive soils using conventional foundations, the moisture content
of the subgrade soils should be equal to or greater than optimum moisture content to a
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GeoSoiis, Inc.
depth below subgrade of 12 inches for one-story structures and 18 inches for two-story
structures, prior to pouring concrete. This soil moisture content should be verified by a GSI
representative. Once pre-construction testing is completed the visqueen barrier should
_ be placed on the moistened soil within 72 hours and the slab should be poured within 72
hours.
TRENCH BACKFILL
1. Utility trench backfill within the influence of structures (buildings and
appurtenances), slopes, and beneath hard scape 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 of trench
backfill is not recommended for the site soil materials. Uniform sand backfill (SIP or
SM) should not be utilized, other than immediately above and below pipelines,
(approximately 1-foot thick).
2. 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 a
foundation for a retaining wall, building, or key appurtenant structures.
3. When excavating trenches, the contractor should conform to CAL-OSHA, local
safety codes, and grading ordinances.
4. The utilities will be backfilled utilizing on site soils and tested by the geotechnical
consultant to insure that trench backfill is compacted to a minimum of 90 percent
relative compaction, or as required by the governing agency. The bedding
dimensions and setbacks of trenches should follow the City of Lake Elsinore
ordinances and utility company requirements unless superseded herein.
5. Utilities crossing grade beams, perimeter beams, or footings should either pass
below the footing or grade beam utilizing a hardened collar or foam spacer, or pass
through the footing or grade beam in accordance with the recommendations of the
structural engineer.
PLAN REVIEW
Specific grading and foundation plans should be submitted to this office for review and
comment, as they become available, to minimize any misunderstandings between the
plans and recommendations presented herein. In addition, all foundation excavations and
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.
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INVESTIGATION LIMITATIONS
The materials encountered on the project site and utilized in our laboratory are believed
_ representative of the total area; however, soil materials may vary in characteristics between
excavations. Inasmuch as our investigation is based upon the site materials observed,
selective laboratory testing, and engineering analyses, the recommendations are
professional opinions. It is possible that variations in the soil conditions could exist beyond
the points explored in this investigation. Also, changes in groundwater conditions could
occur at some time in the near future due to variations in temperature, regional rainfall, and
other factors.
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 assumes no responsibility or liability for work or testing performed by others.
In addition, this report may be subject to review by the controlling authorities.
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GeoSoiis, Inc.
AS. w 6L9 . '-- \ i!A.1 I y,n a, t ! .
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LEGEND
Q I V Quaternary alluvial deposits
L-� 4D Approximate location of boring by LOR Geotechnical (1994) LOSANGELESCO.
RNERSIDE CO.
• ORANGE CO.
B" 10 Approximate location of boring by GSI (1998) 'L=S SANDIEGOCO.
•-•... Approximate boundary of soils subject to collapse GEOTECHNICAL MAP
Plate 1
W.O. 2492-A-SC DATE 9/98 SCALE V=100'
APPENDIX A
REFERENCES
APPENDIX A
REFERENCES
Blake, T.F., 1989, EQFAULT, A computer program for the deterministic prediction of peak
horizontal acceleration from digitized California faults; Updated through 1993.
Blake, T.F., 1989, EQSEARCH, A computer program for the estimation of peak horizontal
acceleration from California historical earthquake catalogs; Updated through 1998.
Blake, T.F., 1989, FRISK89, A computer program for the probabilistic estimation of seismic
hazard using faults as earthquake sources; Updated, 1993.
Campbell, K.W., 1993, Empirical prediction of near-source ground motion from large
_ earthquakes; Proceedings, International Workshop on Earthquake Hazard and
Large Dams in the Himalaya, sponsored by the Indian National Trust for Art and
Cultural Heritage (INTACH), New Delhi, India, January 15-16.
Campbell, K.W. and Bozorgnia, Y., 1994, Near-Source Attenuation of Peak Horizontal
Acceleration From Worldwide Accelerograms Recorded From 1957 to 1993;
Proceedings, Fifth U.S. National Conference on Earthquake Engineering, Vol. III,
Earthquake Engineering Research Institute, pp. 283-292.
Canty Engineering Group, Inc., 1998, Torn Ranch, Rough Grading Plan, prints dated
August 28.
GeoSoils, Inc., 1998, Preliminary Estimate of Earthwork Balance and Remedial Grading
Recommendations, Torn Ranch Property, City of Lake Elsinore, Riverside County,
California, W.O. 2492-B-SC, dated September 23.
Hart, E.W. and Bryant, W.A., 1997, Fault-Rupture Hazard Zones in California, Alquist-Priolo
Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps; California
Division of Mines and Geology Special Publication 42.
Jennings, C.W., 1994, Fault activity map of California and adjacent areas, scale 1 :750,000,
California Division of Mines and Geology, California Data Map Series, Map No. 6.
_ Joyner, W.B, and Boore, D.M., 1982a, Estimation of Response-Spectral Values as
Functions of Magnitude, Distance and Site Conditions, in eds., Johnson, J.A.,
Campbell, K.W., and Blake, T.F.: AEG Short Course, Seismic Hazard Analysis, June
18, 1994.
1982b. Prediction of Earthquake Response Spectra, U.S. Geological Survey Open-
File Report 82-977, 16p.
LOR Geotechnical Group, Inc., 1994a, Supplemental Geotechnical Investigation, Torn
Ranch Property, Lake Elsinore, California, Project No. 30538.13, dated July 1 .
_ GeoSoils, Inc.
_ 1994b, Preliminary Geotechnical Investigation, Torn Ranch Property, Lake Elsinore,
California, Project No. 30538.12, dated April 14.
Norris. R.M. and Webb, R.W., 1990, Geology of California, Second Edition, John Wiley &
Sons, Inc., 540p.
Weber, H.F., Jr., 1977, Seismic hazards related to geologic factors, Elsinore and Chino
fault zones, northwestern Riverside County, California, California Division of Mines
and Geology Open-File Report 77-4, 96p.
Uniform Building Code, 1997, International Conference of Building Officials, dated April.
United States Department of Agricultural, 1980, aerial photographs, region 615020, flight
line 180, photo numbers 194 and 195, scale 1" = 3,333 ± feet.
Torn Ranch Builders, LLC Appendix A
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APPENDIX B
BORING LOGS
BORING LOG
GeoSoils, Inc.
W.O. 2492-A-SC
_ PROJECT:TORN RANCH BORING B-1 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-3-98
Sample SAMPLE METHOD: California Sampler
.. + v
aC Standard Penetration Test
- o c
+ + m —
\ — C ? +e Water Seepage into hole-Ca m to o o + L Undisturbed,Ring Sample
+ x --Jo 3 rn-0 a m 7
0. - 'O L O U E v •- +
m 3 C �� — V) 31 L 0 Description of Material
COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
@ 0', SILTY SAND, light brown, dry, medium dense; some
organics, rootlets.
16 SM 116.2 1.3 8.1 N. @ 2', as per 0'.
ALLUVIUM
@ 3', SILTY SAND with gravel, reddish brown, dry, medium
dense; gravel to 1" in diameter.
5
12 SM 105.0 3.7 17.2 . @ 5', as per 3'.
f.
— 10
25 123.0 2.8 21.3 @ 10', SILTY SAND with gravel, light tan to light brown, dry,
. medium dense.
s
— 15
56 CL 117.2 14.8 95.5 @ 15', SANDY CLAY, reddish brown, wet, hard.
20 70 CL , 116.6 12.3 77.4 ' ; @ 20', SANDY CLAY, reddish brown to grayish brown
i�% mottled, wet, hard; mottled appearance.
Total Depth = 21'
No groundwater encountered
Backfilled 9-3-98
�• 25
I I
I
Lake Elsinore GeoSoils, Inc. PLATE B-,
—
BORING LOG
GeoSoils, Inc.
W.O. 2492-A-SC
I
PROJECT.•TORN RANCH BORING B-2 SHEET 1 OF 1
— Lake Elsinore
DATE EXCAVATED 9-3-98
Sample X SAMPLE METHOD: California Sampler
s C Standard Penetration Test
+ o
}^ L t Water Seepage into hole
`— L (D: o 3 r-7 Undisturbed, Ring Sample
1- AC •- o 3 V)J I 31
a tll
a U IS L; O L) " — +'
0 7 C :V — V, � L O a Description of Material
O m 7 t m 7 0 I O E 1 Vl
17 SM 105.3 2.9 13.3 f COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
@ 0', SILTY SAND, light brown, dry, medium dense; some
organics, roots.
17 106.9 4.8 23.2 s @ 3', as per 0'.
M/S 11 ALLUVIUM
5 @ 4', SAND/SILTY SAND, brown to light tan, dry, medium
dense.
10 30 112.4 3.1 17.4 @ 10', as per 4'.
15
20 SP 103.2 4.4 19.1 @ 15', SAND, light tan, dry, medium dense; medium to
coarse grained.
20 30 110.8 3.0 16.1 @ 20', as per 15', dry.
Total Depth = 21'
No groundwater encountered
Backfilled 9-3-98
25-4
I � I
I � I
_i
Lake Elsinore GeoSoils, Inc. PLATE B-2 i
4
BORING LOG
.. GeoSoils, Inc.
W.O. 2492-A-SC
PROJECT.TORN RANCH BORING 8-3 SHEET 1 OF
` Lake Elsinore
DATE EXCAVATED 9-3-98
Sample SAMPLE METHOD: California Sampler
.. ..
a C Standard Penetration Test
t o
w `—"^ L + ® % Water Seepage into hole
m ♦ — C j 0 Undisturbed, Ring Sample
t W 0FA O 7 V 4- L
+ �z •-D 3 (A.0 a UI 7
a - 'O L O U E 3)" •- {'
of 3 C J — 0 3 L o 0 Description of Material
Cl 0] 7 t m 7 U) 0 E N
COLLUVIUM/ALLUVIUM (UNDIFFERENTAIATEDI
@ 0', SILTY SAND, light brown, damp, medium dense; very
fine grained.
13 SM 120.7 4.9 35.2 @ 2', as per 0'.
` i
s
f
5 I 16 SP 115.1 2.5 15.4 ALLUVIUM
@ 5', SILTY SAND, brown to reddish brown, dry, medium
dense; very fine grained.
T-
10 38 101.3 6.3 26.4 @ 10', SAND with gravel, light tan, damp, dense; gravel to
1" in diameter.
15z 21 P/S 100.7 4.7 19.5 @ 15', SAND/SILTY SAND, light tan to reddish brown, dry,
medium dense; fine to coarse grained.
20 _
4/10 5M/ 126.3 3.9 33.5 I= @ 20', SILTY SAND/SANDY GRAVEL, light tan to reddish
GM =� brown, damp, dense; mottled appearance.
=�1
_11
25 =�
54/9', SP 115.0 1 4.1 124.6 @ 25', SAND/SANDY GRAVEL, light tan to reddish brown,
i dry, dense; fine to coarse grained.
Ic 1
t { 1
I I I
Lake Elsinore GeoSoils, Inc. PLATE B-3
BORING LOG
GeoSoils, Inc.
W.O. 2492-A-Sc
PROJECT:TORN RANCH BORING B-3 SHEET 2 OF 2
Lake Elsinore
DATE EXCAVATED 9-3-98
Sample SAMPLE METHOD: California Sampler
s C Standard Penetration Test
o
±.. N Water Seepage into hole
i v \ — c`- o of ® Undisturbed, Ring Sample
L 01 01 01 O D O 4- L
+- -z •-J3 3 V)A CL O 7
a - U L O () E :2
m 3 c 3 - 0 3 L O Description of Material
O M 7t m 70 0 E Vl
54/6 SP :: @ 30, no recovery due to gravel.
35 /-,54/6' GM 2.8 � 35', SANDY GRAVEL, reddish brown, dry, dense; gravel to
'
2" in diameter.
I
1
40 54/6' 2.6 @ 40', SANDY GRAVEL, dark olive brown, dry, dense.
45 54/8 122.6 2.8 21.0 $ @ 45', SANDY GRAVEL, light tan to reddish brown, dry,
1 dense; medium to coarse grained, gravel to 1" in diameter.
50 �54/5 1 @ 50', no recovery due to gravel.
Total Depth = 51'
No groundwater encountered
Backfilled 9-3-98
�— 55
I I
I
i
Lake Elsinore GeoSoils, Inc. PLATE B-4 __
BORING LOG
GeoSoils, Inc.
W O. 2492-A-SC
PROJECT:TORN RANCH BORING 8-4 SHEET 1 OF 1
` Lake Elsinore
DATE EXCAVATED 9-3-98
�- Sample SAMPLE METHOD: California Sampler
} v ,.
a 0 Standard Penetration Test
4-
-^ L + Water Seepage into hole
i - C 4 0 0 �/�' Undisturbed, Ring Sample
t W ®! IA O 7 O t L rii^
Y •- 3 0.0 a o 7
a - M L; O U a 3`� •- 4-
0 7 C �! — w 31 L o a Description of Material
O to +; m Z)N O F 0
COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
@ 0', SILTY SAND, light brown, dry, medium dense.
13 SM 109.1 2.6 13.4 @ 2', as per 0'.
sM s ALLUVIUM
5 @ 4', SILTY SAND, light brown, dry, medium dense.
18 105.1 4.1 18.8 @ 7', as per 4'.
_ s.
jr
10
:s
10 104.1 5.7 25.8 @ 12', SILTY SAND, reddish brown, dry to damp, loose, very
r fine grained.
s
15
15 109.2 7.1 36.4 @ 17', SILTY SAND, reddish brown, damp, medium dense;
fine to coarse grained.
r•
.f.
20 20 SP 102.6 2.0 8.7 .: @ 20', SAND, light tan to reddish tan, dry, medium dense.
Total Depth = 21'
No groundwater encountered
Backfilled 9-3-98
25
I
i
l Lake Elsinore GeoSoils, Inc. PLATE B-5
BORING LOG
GeoSoils, Inc.
W.O. 2492-A-SC
PROJECT:TORN RANCH BORING B-5 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-3-98
Sample ! SAMPLE METHOD: California Sampler
.. v ..
s c Standard Penetration Test
0
.+. ±^ L + ® Water Seepage into hole
v — C 0 ro Undisturbed,Ring Sample '
L 0 0 00 D + L
+- aC •-M 3 0 .0 a a �
a - V L 0 U E ]v - +-
m c 0 — 03 L 0 toDescription of Material
o m In+ m 3 rn 0 E 0
j 41 SM 108.6 1.3 6.8 COLLUVIUM/ALLUVIUM (UNDIFFERENTIATEDI
s .
@ 0', SILTY SAND, light brown, dry, dense.
SM ' ALLUVIUM
@ 3', SILTY SAND, light brown to reddish brown, damp,
loose.
5
10 116.7 7.2 45.3 @ 5', as per 3'.
I s
f.
.f.
f
^c 24 M/S 114.3 6.3 37.2 .N @ 10', SAND/SILTY SAND, light tan to reddish brown, damp,
medium dense; fine to coarse grained.
i
_ I
I
... 15 �
26 SP 99.9 12.7 10.8 @ 15', SAND, light tan, dry, medium dense, medium to
coarse grained.
i
20
52 120.7 2.6 18.6 @ 20 , SANDY GRAVEL, light tan to light reddish brown, dry,
dense.
Total Depth = 21'
No groundwater encountered
Backfilled 9-3-98
251
i
i
- � I
Lake Elsinore GeoSoils, Inc. PLATE B-6
BORING LOG
GeoSoils, Inc.
W.O. 2492-A-SC
PROJECT.-TORN RANCH BORING B-6 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-3-98
... Sample SAMPLE METHOD: California Sampler
+- a o Standard Penetration Test
4- ±,� L Water Seepage into hole
� 0 < < Undisturbed,Ring Sample
+ x --J3 3 y� 4 a 7
a — 'D L O L' E a" —
Descri tion of Material
m 7 C 3 — N 3 L 0 m p
O m 7 t m :3 0 O E Vl
COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
s
@ 0', SILTY SAND, light brown, dry, medium dense.
N.
.f.
13 SM 100.4 4.6 19.0 : '' @ 3', as per 0'.
s
5 12 SM 113.5 3.7 21.5 ALLUVIUM
@ 5', SILTY SAND, brown to reddish brown, dry, medium
dense.
f
10
12 108.3 7.2 35.9 : @ 12', as per 5', damp.
15-
9 106.3 6.6 31.5 _ @ 15', SILTY SAND, reddish brown, damp, loose.
s
20 i 12 109.8 4.6 24.1 @ 20', SILTY SAND, reddish brown, dry, medium dense, fine
to medium grained.
i Total Depth = 21,
No groundwater encountered
j Backfilled 9-3-98
I
i
... 25
i
f GeoSoils, Inc.
Lake Elsinore PLATE B-7
_ GeoSoils, Inc. BORING LOG
W.O. 2492-A-SC
PROJECT.-TORN RANCH BORING B-7 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-3-98
I
Sample SAMPLE METHOD: California Sampler
^ a C ® Standard Penetration Test
t o
4- '-^ L + Water Seepage into hole
i v \ — c o a ® Undisturbed,Ring Sample
L of m O 7 + L
+ Y -M 3 FA. a O 7
IL - 'D L O U E T" - +
o° to inI rn oL ran Description of Material
I 10 SM 103.8 1.3 5.8 COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
r: @ 0', SILTY SAND, light brown, dry, loose.
N
r.
s
f "
5 12 108.0 3.0 15.1 ALLUVIUM
s : @ 5', SILTY SAND, light brown, dry, medium dense.
s .
.f.
s
f.
_ 10 8 SM 104.0 11.1 50.0 @ 10', SILTY SAND, reddish brown, damp, loose, fine to
s. medium grained.
s
15
16 102.7 12.6 54.7 @ 15', SILTY SAND, reddish brown, moist, medium dense,
fine to coarse grained.
s
20 " 14 112.1 9.8 54.3 s @ 20', as per 15', fine to very coarse grained.
Total Depth = 21'
No grundwater encountered
Backfilled 9-3-98
... 25 I I
I
I l
GeoSoils, Inc.
s-s
Lake Elsinore PLATE
BORING LOG
GeoSoils, Inc.
WO. 2492-A-SC
PROJECT:TORN RANCH BORING B-8 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-4-98
Sample SAMPLE METHOD: California Sampler
aC Standard Penetration Test
4- +^ L + Water Seepage into hole
r w mi a o C o 2 Undisturbed,Ring Sample
+ Y • .O' 3 w M
0. - 'D L O U E :D - +
m 7 C :1 — N 0) L Description of Material
COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
@ 0', SILTY SAND, light brown to brown, dry, loose.
s:
1 1 SM 2.9 @ 3', as per 0'.
SM ALLUVIUM
5 s: @ 4', SILTY SAND, brown to reddish brown, moist, loose.
9 106.5 10.8 51.9 @ 7', as per 4'.
13 107.7 13.6 67.1 @ 10', SILTY SAND, reddish brown, moist, medium dense;
fine to medium grained.
15 21 SM/S 111.0 4.2 22.6 @ 15" SAND/SILTY SAND, light tan to reddish brown, dry,
medium dense; fine to coarse grained.
_
20 31 110.3 2.9 15.4 @ 20', as per 15'.
Total Depth = 21'
No groundwater encountered
Backfilled 9-4-98
25 I l
I ( �
I
GeoSoils, Inc. '
Lake Elsinore PLATE B-9
BORING LOG
GeoSoils, Inc.
W O. 2492-A-SC
PROJECT.-TORN RANCH BORING B-9 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-4-98
Sample x SAMPLE METHOD: California Sampler
^ } ., v
3 0 ~ Standard Penetration Test
+- a
w ±^ I L Ot, Water Seepage into hole
1 vi — c J a � Undisturbed, Ring Sample
L !to ml to � L _!
4- Y •—M; 3 N M a Ol 7
4 — M L� O U E 3" — +
o m' }I m 0 rn L s° y Description of Material
COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
@ 0', SANDY GRAVEL, light tan, dry, medium dense; gravel
to 2" in diameter.
Rz 26 SP 1.9 ALLUVIUM
5 @ 4', SAND/SILTY SAND, light tan to brown, dry, medium
dense.
16 SP 109.7 3.4 17.9 @ 7', SILTY SAND, brown to reddish brown, wet, medium
f . dense.
s-
10 f ', as per 7'.
18 SM 110.9 14.9 80.5 .-�: @ 10 P
f:
r-
s
r
r
r
r
15 I ;
10 ( N. @ 15', no recovery
f.
r
.i^
r
r.
20 28 P/GT 118.4 1 5.1 134.0 @ 20', SILTY SAND/GRAVELLY SAND, brown to dark tan,
damp, medium dense; gravel to 1" in diameter.
Total Depth = 21'
No groundwater encountered
Backfilled 9-4-98
25-1
I j I
i
Lake Elsinore GeoSoils, Inc. B-10
PLATE
— GeoSoils, Inc. BORING LOG
W.O. 2492-A-SC
_ PROJECT:TORN RANCH BORING B-10 SHEET 1 OF 1
Lake Elsinore
DATE EXCAVATED 9-4-98
Sample SAMPLE METHOD: California Sampler
^ I a C 033 Standard Penetration Test
_o
a + ` Water Seepage into hole
L on
i o C o } a Undisturbed,Ring Sample
4- x —J3 a rna a a :3
G. — O L O U E 3 v — +
o 3 c 3 - y 31 L o . Description of Material
o m :+ m DO I o E y
8 SM 96.1 4.0 14.7 COLLUVIUM/ALLUVIUM (UNDIFFERENTIATED)
s
@ 0', SILTY SAND, light brown to brown, dry, loose.
r
SM ALLUVIUM
5 8 108.9 11.4 58.1 .�. @ 4', SILTY SAND, brown to reddish brown, moist, loose.
s
@ 5', as per 4'.
r.
r
r
10 35 2.2 @ 10', SILTY SAND with gravel, reddish brown, dry, medium
dense; gravel to 2" in diameter.
t..
15 38
N. @ 15', no recovery due to gravel.
s
20 I f.
60 1.0 @ 20', SANDY GRAVEL, brown to light tan, dry, dense;
-MIgravel to 2" in diameter.
Total Depth = 21'
.. i No groundwater encountered
Backfilled 9-4-98
i
t
` 125
I
t
i
i i I
i I
GeoSoils, Inc.
Lake Elsinore PLATE
APPENDIX C
EQFAULT, EQSEARCH, FRISK89
o N
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LOG N = 3.478 - 0.725M
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p 0.1
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> 0.01
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0.001
0.0001
— 3.0 4.0 5.0 6.0 7.0 8.0 9.0
MAGNITUDE (M)
SEISMIC RECURRENCE CURVE
HISTORICAL EARTHQUAKES FROM 1800 TO 1998
Torn Rcnch
Plate C-2
11� O� O� M Z N
a + r co Ln +
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AVEIRAGE RETURN PERIOD vs. ACCELERATION
1000000a
6
4
V
0 100000 e
6
2
0
(j:� 10000 e
Lli e
�- 4
z p
1000 a
[L 4
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< 100a
4 Ar
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0.0 0.1 0.2 0.3 0.4
ACCELERATION (g)
a�
Torn Ranch
n JOYNER & BOORE (1982) RND. MEAN JOB No.: 2492—A—SC
APPENDIX D
GENERAL EARTHWORK AND GRADING GUIDELINES
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's 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
Torn Ranch Builders, LLC Appendix D
File:e:\wpTmurr\rc2400\2492a.pgi Page 2
GeoSoiils, 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 112 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
Torn Ranch Builders, LLC Appendix D
File:e:1,wp7\murr\rc2400\2492a.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 be taken 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.
Torn Ranch Builders, LLC Appendix D
File: e:\wp7\murr\rc2400\2492a.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:
1. 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.
-- Torn Ranch Builders, LLC Appendix D
File:eAwp7\murr\rc2400\2492a.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.
SUBDRAIN 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.
Torn Ranch Builders, LLC Appendix D
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GeoSoiis, 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 ar..d possible fatality
on grading and construction projects. GSI recognizes that construction activities will vary
on each site and that site safety is the rp ime 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.
Torn Ranch Builders, LLC Appendix D
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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
Torn Ranch Builders, LLC Appendix D
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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.
Torn Ranch Builders, LLC Appendix D
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GeoSoils, I>ne.
CANYON SUBDRAIN DETAIL
TYPE A ,
— ------------ ---------------- --
PROPOSED COMPACTED FILLloe
—NATURAL GROUND i
i
COLLUVIUM AND ALLUVIUM (REMOVE)
BEDROCK
TYPICAL BENCHING
SE= ALTERNATIVES
TYPE B
PROPOSED COMPACTED FILL
NATURAL GROUND
i �I :o-,
COLLUVIUM AND ALLUVIUM (REMOVE) ol
.10
��
BEoaocx
TYPICAL BENCHING
SEE ALTERNATIVES
NOTE: ALTERNATIVES. LOCATICN AND EXTENT OF SUBORAINS SHOULD BE DETERMINED
BY THE SOILS ENGINEER ANO/OR ENGINEERING GEOLOGIST DURING GRADING.
PLATE EG-1
CANYON SUBDRAIN ALTERNATE DETAILS
ALTERNATE 1: PERFORATED PIPE AND FILTER MATERIAL
12' MINIMUM
6' INIMUM FILTER MATERIAL: MINIMUM VOLUME OF 9 FT.'
/LINEAR FT. 6' � ASS OR PVC PIPE OR APPROVED
SUBSTITUTE WITH MINIMUM 8 (1/4' ) PERFS.
MINIMUM LINEAR F T. IN BOTTOM HALF- OF PIPE.
�n ASTM 02751, SDR 35 OR ASTM 01527, SCHD, 40 6' MINIMUM
A-1 ASTM 03034, SDR 35 OR ASTM 01785, SCHD. 40
FOR CONTINUOUS RUN IN EXCESS OF 500 FT. B—�
USE 8' .� PIPE
FILTER MATERIAL
SIEVE SIZE PERCENT PASSING
1 INCH 100
3/4 INCH 90-100
3/3 INCH 40-100
NO. 4 25-40.
NO. 8 18-33
NO. 30 5-15
NO. 50 .0-7
NO. 200 - 0-3
ALTERNATE 2: PERFORATED PIPE, GRAVEL AND. FILTER FABRIC
V, 6 ' MINIMUM OVERLAP 6' MINIMUM OVERLAP~'-�
6' MINIMUM COVER \
_ -4' MINIMUM BEDDING 4' MINIMUM BEDDING ••� ' \�
A-2 GRAVEL MATERIAL 9 FT'/LINEAR FT" B-2
PERFORATED PIPE: SEE ALTERNATE 1
GRAVEL: CLEAN 3/4 INCH ROCK OR APPROVED SUBSTITUTE
FILTER FABRIC: MIRA=1 140 CR APPROVED SUBSTITUTE
PLATE EG- 2
DETAIL FOR FILL SLOPE TOEING OUT
ON FLAT ALLUVIATED CANYON
TOE OF SLOPE AS SHOWN ON GRADING PLAN COMPACTED FILL
ORIGINAL GROUND SURFACE TO BE
RESTORED WITH COMPACTED FILL ORIGINAL GROUND SURFACE
BACKCUT` VARIES. FOR DEEP REMOVALS, 1�41
_ BACKCUT ~SHOULD BE MADE NO
STEEPER THA :1 OR AS NECESSARY ANTICIPATED ALLUVIAL REMOVAL
FOR SAFETY `,CONSIDERATIONS/ DEPTH PER SOIL ENGNdEER.
PROVIDE A 1:1 MINIMUM PROJECTION FROM TOE OF
1 SLOPE AS SHOWN ON GRADING PLAN TO THE RECUMMENDED
REMOVAL DEPTH. SLOPE HEIGHT, SITE CONDITIONS AND/OR
LOCAL CONDITIONS COULD DICTATE FLATTER PROJECTIONS.
REMOVAL ADJACENT TO EXISTING FILL
ADJOINING CANYON FILL
PROPOSED ADDITIONAL COMPACTED FILL
COMPACTED FILL LIMITS LINE\
TEMPORARY COMPACTED FILL �
FOR DRAINAGE ONLY
Qaf G, Qaf / Qai (TO BE REMOVFD)
(EXISTING COMPACTED FILL)
LEGE'ND
�, ��� / TO 3E REMOVED BEFORE Oaf AR1'II-iCIAL FILL
PLACING ADDITIONAL
COMPACTED FILL Qal ALLUVIUM
PLATE EG- 3
0
W w
0 W
Z Z W
W O a W
Z a >
Q W
U J Q
W Z
W O J tr
cr Ln I H W
H
LL W I p Q
— Q —i ❑ W
I— LL } ' ~ N
m C� Q
W O Z w I Z cx
O ?
Q Z O Y 2 LL Q
W F- Z I U c
X J J w aW O
J a- m m I
J O \ t Z ppm
U U Z Z
LL ttA Z / } 2
W
U) Z Q ~ w
Q � O W
)� 2
Q
LLIJ 2 ? O
Q t7
��yy > > = '
LL (r O
w cr H
Z
Z LL 2 U W
O O ❑
W O cr
O 2 C4 J O W
m w Y
m
X
2 � 2
O a W Z
ZCD
O 075
c
r _ L
0 cr-
LL O
f 0 a N
Q W W
U 0 to J
N Q LL a a w \ N
— a
W w of ►- 2
—! W
in w — 2
p O to O O
F- z cr
— Q
Q0 O C 2
w } 2
( n W W Z
v ' J m O N
!- N
O W
0 ,
— Q n
w
3
U_
- \\
J
Q av
U w�
}
H
N
to I
LATE EG- 4
TYPICAL STABILIZATION I BUTTRESS SUBDRAIN DETAIL
FILTER MATERIAL: MINIMUM OF FIVE Ft'/LINEAR Ft OF PIPF
2 41NIM111• OR FOUR Ft'/LINEAR Ft OF PIPE WHEN PLACED IN SQUARE FILTER MATERIAL SHALL BE OF
.� CUT TRENCH. THE FOLLOWING SPECIFICATION
• ••
9j,I'ERjJATIVE IN LIEU OF FILTER MATERIAL;: GRAVEL MAY BE OR AN APPROVED EQUIVALENT:
• •'� •' ENCASED IN APPROVED FILTER FABRIC. FILTER FABRIC SIEVE SIZE PERCENT PASSING
SHALL BE MIRAFI 140 OR EQUIVALENT. FILTER FABRIC 1 INCH 100
SIIIALL BE LAPPED A MINIMUM OF 12' ON ALL JOINTS. 3/4 INCH 90-100
4 ' 1•11NIMUH 2' MINIMUM MINIMUM 4' DIAMETER PIPE: ABS-ASTM D-2751, SDR 35 3/8 INCH 40-100
PIPE OR ASTM D-1527 SCHEDULE 40 PVC-ASTM D-3034, NO. 4 25-40
SOR 35 OR ASTM D-1785 SCHEDULE 40 WITH A CRUSHING NO. 8 18-33
STRENGTH OF 1,000 POUNDS MINIMUM, AND A MINIMUM OF NO. 30 5-15
. H1N1MIJH 8 UNIFORMLY SPACED PERFORATIONS PER FOOT OF PIPE NO. 50 0-7
PIPE INSTALLED WITH PERFORATIONS OF BOTTOM OF PIPE. NO. 200 0-3
gllU PROVIDE CAP AT UPSTREAM END OF PIPE. SLOPE AT 2%
TO OUTLET PIPE. OUTLET PIPE TO BE CONNECTED TO GRAVEL_ SHALL BE OF THE
z SUBDRAIN PIPE WITH TEE OR ELBOW. FOLLOWING SPECIFICATION OR
NOTE: 1. TRENCH FOR OUTLET PIPES TO BE BACKFILLED AN APPROVED EQUIVALENT:
WITH ON-SITE SOIL. SIEVE SIZE PERCENT PASSINJ
-� 2' MINIMUM 2. BACKDRAINS AND LATERAL DRAINS SHALL BE 1 1/2 INCH 100
r LOCATED AT ELEVATION OF EVERY BENCH DRAIN. NO, 4 50
D FIRST DRAIN LOCATED AT ELEVATION JUST ABOVE NO. 200 8
(�l LOWER LOT GRADE. ADDITIONAL DRAINS MAY BE
Rl SAND EQUIVALENT: MINIMUM OF 50
C;) REQUIRED AT THE DISCRETION OF THE SOILS
ENGINEER AND/OR ENGINEERING GEOLOGIST.
Ul
FILL OVER NATURAL DETAIL
SIDCHILL FILL
COMPACTED FILL
PROPOSED GRADE
MAINTAIN MINIMUM 15' WIDTH
TOE OF SLOPE AS SHOWN ON GRADING PLAN SLOPE TO BENCH/BACKCUT
PROVIDE A 1:1 MINIMUM PROJECTION FROM
DESIGN TOE OF SLOPE TO TOE OF KEY
AS SHOWN ON AS BUILT M O�
NATURAL SLOPE TO jOPSO\\-. COLL�VIU 4' MINIMl1M
BE RESTORED WITH
COMPACTED FILL
BENCH WIDTH MAY VARY
BACKCUT VARIES
T3�MINIMUM
/ 4 NOTE: 1, WHERE THE NATURAL SLOPE APPROACHES OR EXCEEDS THE
1 ' MINIMUM KEY WIDTH DESIGN SLOPE RATIO, SPECIAL RECOMMENDATIONS WOULD BE
_0 2'X 3' MINIMUM KEY DEPTH PROVIDED BY THE SOILS ENGINEER.
r- 2. THE NEED FOR AND DISPOSITION OF DRAINS WOULD BE DETERMINED
�T� 2' MiNs'MUM IN BEDROCK OR BY THE SOILS ENGINEER BASED UPON EXPOSED CONDITIONS.
FT,. APPROVED MATERIAL.
G)
C71
I I ! I I I I I I
FILL OVER CUT DETAIL
(I1 FILL. CONTACT MAINTAIN MINIMUM 15' FILL SECTION FROM
1, AS SHOWN ON GRADING PLAN BACKCUT TO FACE OF FINISH SLOPE
2. AS SHOWN ON AS BUILT
PROPOSED GRADE COMPACTED FILL
pR L' MINIMUM
ORIGINAL TOPOGRAPHY 7 \
MINIMUM
_ CUT SLOPE / // � BENCH WIDTH MAY VARY
I LOWEST BENCH WIDTH
r`
15- MINIMUM OR H/2
BEDROCK OR APPROVED MATERIAL
NOTE: THE CUT PORTION OF THE SLOPE SHOULD BE EXCAVATED AND
(- EVALUATED BY THE SOILS ENGINEER AND/OR ENGINEERING
.ram
GEOLOGIST PRIOR TO CONSTRUCTING THE FILL PORTION.
n-�
m
c�
i
STABILIZATION FILL FOR UNSTABLE MATERIAL
EXPOSED IN PORTION OF CUT SLOPE
REMOVE: UNSTABLE MATEF IAL
NATURAL SLOPE
15' MINIMUM
PO. D H ('RADE
UNWEATHERED BEDROCK
OR APPROVED MATERIAL
H2 /
REMOVE: UNSTABLE
MATERIAL / COMPACTED STABILIZATION FILL
- - - 1' MINIMUM TILTED BACK
IF RECOMMENDED BY THE SOILS ENGINEER AND/OR ENGINEERING
W2
,{ GEOLOGIST, THE REMAINING CUT PORTION OF THE SLOPE MAY
fU //� / W1 REQUIRE REMOVAL AND REPLACEMENT WITH COMPACTED FILL.
D
FT] NOTE: 1. SUBDRAINS ARE NOT REQUIRED UNLESS SPECIFIED BY SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST,
FTI 2. 'W' SMALL BE EQUIPMENT WIDTH (151 FOR SLOPE HEIGHTS LESS THAN 25 FEET. FOR SLOPES GREATER
G)
I THAN 25 FEET 'W' SHALL BE DETERMINED BY THE PROJECT SOILS ENGINEER AND /OR ENGINEERING
CO GEOLOGIST. AT NO TIME SHALL 'W' BE LESS THAN H/2.
SKIN FILL OF NATURAL GROUND
ORIGINAL SLOPE
ROPOSED FINISH GRADE
3' MINIM(IM
15' MINIMUM TO BE MAINTAINED FROM
PROPOSED FINISH SLOPE FACE TO BACKCUT
PROPOSED FINISH SLOPE C BEDROCK OR APPROVED MATERIAL
i 2' HINIMUM ��` \ 3' MINIMUM KEY DEPTH
KEY DEPTH
15� ti NIMUM KEY WIDTH
_0 / NOTE: 1. THE NEED AND DISPOSITION OF DRAINS WILL BE DETERMINED! BY THE SOILS ENGINEER AND/OR
FENGINEERING GEOLOGIST BASED ON FIELD CONDITIONS.
--1 2. PAD OVEREXCAVATION AND RECOMPACTION SHOULD BE PERFORMED IF DETERMINED TO BE
Fri NECESSARY BY THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST.
m
c)
I
(o
DAYLIGHT CUT LOT DETAIL
NATURAL GRADE /
RECONSTRUCT COMPACTED FILL SLOPE AT 2:1 OR FLATTER /�
(HAY INCREASE OR DECREASE PAD AREA). /
OVEREXCAVATE AND RECOIAPACT
REPLACEMENT FILL PROPOSED FINISH GRADE
AVOID AND/OR CLEAN UP SPILLAGE OF / 0\11•j 3' MINIMUM BLANKET FILL
MATERIALS ON THENATURAL SLOPE \O�// GO�,�. �� �\ TJ����/����'T �T���/�
Qq �OQ / \ // BEDROCK OR APPROVED MATERIAL
TYPICAL BENCHING
2' MINIMUM
�'� 296 GRADI�NT
KEY D E P T I I ___�._
I�
r
D NOTE: I. Sl1BDRAlIJ AND KEY WIDTH REQUIREMENTS WILL BE DETERMINED BASSO ON EXPOSED SUBSURFACE
r� CONDITIONS AND THICKNESS OF OVERBURDEN.
[Tl
Tl 2. PAD OVER EXCAVATION AND RECOMPACTION SI4OULD BE PERFORMED IF DETERMINED NECESSARY BY
G7 THE SOiLS ENGINEER AND/OR THE ENGINEERING GEOLOGIST.
O
_ TRANSITION LOT DETAIL
CUT LOT (MATERIAL TYPE TRANSITION)
NATURAL GRAD
5' MINIM M
_ PAO GRADE
OVEREXCAVATE AND RECOMPACT \
COMPACTED FILL �\ /\ V1l\ /j/\\ // 3' MINIMUM*
UNWEATHERED BEDROCK OR APPROVED MATERIAL
_ TYPICAL BENCHING
CUT-FILL LOT (DAYUGHT TRANSITION)
NATURAL GRADE A��R\ 5' MI MUM
� M
PAD GRADE U
vN5 OVEREXCAVATE
OR AND RECOMPACT
COMPACTED FILL J\JM. � �// 3' MINIMUM*
�P SOIL.
/ UNWEATHERED BEDROCK OR APPROVED MATERIAL
TYPICAL BENCHING
NOTE: * DEEPER OVEREXCAVATION MAY BE RECOMMENDED BY THE SOILS ENGINEER
AND/OR ENGINEERING GEOLOGIST IN STEE? CUT-FILL TRANSITICN AREAS.
PLATE EG-1
OVERSIZE ROCK DISPOSAL
VIEWS ARE DIAGRAMMATIC ONLY. ROCK SHOULD NOT TOUC
AND VOIDS SHOULD BE COMPLETELY FILLED IN.
VIEW NORMAL TO SLOPE FACE
PROPOSED FINISH GRADE
I10' MINIMUM (E)
cY_� cYo cc co °O
1 ' MINIMUM (A)
20'MINIMUM
C ap 0o Cc GG
t F7
15' MINIMUM 00 co C�
5' MINIMUM (C)
BEDROCK R APPROVED MAT RIAL
VIEW PARALLEL TO SLOPE FACE
PROPOSED FINISH GRADE
10' MINIMUM (E) 100' MAXIMUM (B)
_ 3' MINIMUM �
10' MINIMUM
10' MINIMUM�
_ (F)
5' MINIMUM (C)
BEDROCK OR APPROVED MATERIAL
NOTE: (A) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET.
(B) HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SIZE AND TYPE OF
EQUIPMENT USED. LENGTH OF WINDROW SHALL BE NO GREATER THAN 100-
MAXIMUM.
_ (C) IF APPROVED BY THE SOILS ENGINEER AND/OR ENGiNEERNG GEOLOGIST,
WINDROWS MAY BE PLACED DIRECTLY ON COMPETENT MATERIALS CAR 6EDROCK
PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION.
(0) ORIENTATION OF WINDROWS MAY VARY BUT SHALL BE AS RECO1MMENUED BY
THE SOILS ENGINEER AND/OR ENGINEERING GEOLOGIST. STAGGERING OF
WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED.
(E) 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 13E ANY SOIL WHICH HAS A UNIFIED SOIL CLASSIFICATION
SYSTEM (UBC 29-1) DESIGNATION OF SM, SP, SW. GP, OR GW. ALL FILL OVER
AND AROUND ROCK WINDROW SHALL B$ COMPACTED TO 90% RELATIVE
COMPACTION.
(G) AFTER F?LL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE UFT
OF ;=iLL COVERING 'NINOROW, WINDROW SHALL BE PROOF ROLLED WITH A D-9
DOZER OR EQUIVALENT.
(H) OVERSiZ=D ROCK IS DEFINED AS LARGER THAN 12, AND LESS THAN 4 FEET
1N SIZ E. PLATE EG-12
ROCK DISPOSAL PITS
FILL LIFTS COMPACTED OVER
ROCK AFTER EMBEDMENT
- I GRANULAR MATERIAL
. • L ARGc' ROCK - - r - - - - �
-
� I
I COMPACTED FILL
I �
SIZE OF EXCAVATION TO BE COMMENSURATE I
WITH ROCK SIZE. I
I �
I
I �
NOTE: 1. LARGE ROCK IS DEFINED AS ROCK LARGER THAN 4 FEET IN MAXIMUM SIZE.
2. PIT IS EXCAVATED INTO COMPACTED FILL TO A DEPTH EQUAL TO 1/2 OF
ROCK SIZE.
3. GRANULAR SOIL SHOULD BE PUSHED INTO PIT AND DENSiFIED BY FLOODING.
USE A SHEEPSFOOT AROUND ROCK TO AID IN COMPACTIUN.
4. A MINIMUM OF 4 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- 1 3
- SETTLEMENT PLATE AND RISER DETAIL
2'X 2'X 1/4' STEEL PLATE
_ STANDARD 3/4' 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 GRADE
I I MAINTAIN 5' CLEARANCE OF HEAVY EQUIPMENT.
s�MECHANICALLY HAND COMPACT IN 2'VERTICAL
�nr
-� LIFTS OR ALTERNATIVE SUITABLE TO AN
ACCEPTED BY THE SOILS ENGINEER.
I 5 5 I -
- I I
1 I MECHANICALLY HAND COMPACT THE INITIAL 5'
5' I
VERTICAL WITHIN A 5' RADIUS OF PLATE BASE.
L
• BOTTOM OF CLEANOUT
PROVIDE A MINIMUM 1' BEDDING OF COMPACTED SAND
NOTE:
1. LOCATIONS OF SETTLEMENT PLATES SHOULD BE CLEARLY MARKED AND READILY
VISIBLE (RED FLAGGED) TO EQUIPMENT OPERATORS.
2. CONTRACTOR SHOULD MAINTAIN CLEARANCE OF A 5' RADIUS OF PLATE BASE AND
_ WITHIN 5* (VERTICAL) FOR HEAVY EQUIPMENT. FILL WITHIN CLEARANCE AREA SHOULD
BE HAND COMPACTED TO PROJECT SPECIFICATIONS OR COMPACTED BY ALTERNATIVE
APPROVED BY THE SOILS ENGINEER.
3. AFTER 5*(VERTICAL) OF FILL IS IN PLACE. CONTRACTOR SHOULD MAINTAIN A 5' RADIUS
_ EQUIPMENT CLEARANCE FROM RISER.
4. PLACE AND MECHANICALLY HAND COMPACT INITIAL OF FILL PRIOR TO ESTABLISHING
THE INITIAL READING.
5. IN THE EVENT OF DAMAGE TO THE SETTLEMENT PLATE OR EXTENSION RESULTING
FROM EQUIPMENT OPERATING WITHIN THE SPECIFIED CLEARANCE AREA, CONTRACTOR
SHOULD IMMEDIATELY NOTIFY THE SOILS ENGINEER AND SHOULD BE RESPONSIBLE
FOR RESTORING THE SETTLEMENT PLATES TO WORKING ORDER.
b. AN ALTERNATE DESIGN AND METHOD OF INSTALLATION MAY BE PROVIDED AT THE
DISCRETION OF THE SOILS ENGINE-.�.
PLATE EG-14
TYPICAL SURFACE SETT LEMENT MONUMENT
FINISH GRADE
3/3' DIAMETER X 6' LENGTH
_. CARRIAGE BOLT OR EQUIVALENT
DIAMETER X 3 1/2' LENGTH HOLE
CONCRETE BACKFiLL
PLATE EG-15
TEST FIT SAFETY DIAGRAM
SIDE VIEW
VF ic4
5?01L PILL
=: �� TEST F1T�:�:=;=:=�����":"•'
( NOT TO SCALE
— - TOP VIEW
100 F=T
- T
50 FAT 50 FEET
SPOIL TEST P1T: VIEWLE
PILL
FLAG
W
W
APPROXIMATE TER LL
cF T=zj PIT
( NOT TO SCALD )
EG-16
_ OVERSIZE ROCK DISPOSAL
VIEW NORMAL TO SLOPE FACE
PROPOSED FINISH GRADE
110' MINIMUM (E)
c cl=
MINIMUM (A)
- � �
20' MINIMUM (8) (G)
co co oc o0
_ 15' MINIMUM ( cc cp
•�5' MINIMUM (C)
BEDROCK OR APPROVED MATERIAL
VIEW PARALLEL TO SLOPE FACE
PROPOSED FINISH GRADE
10' MINIMUM (E) ! 1 00' MAXIMUM (BL,
15' MINIMUM T MINIMUM O
15' MINIMUM (F)
5' MINIMUM (C)
FROM CA WALL MINIMUM (C)
BEDROCK OR APPROVED MATERIAL
NOTE: (A) ONE EQUIPMENT WIDTH OR A MINIMUM OF 15 FEET,
(9) HEIGHT AND WIDTH MAY VARY DEPENDING ON ROCK SIZE AND TYPE OF
_ EQUIPMENT. LENGTH OF WINDROW SHALL BE NO GREATER THAN 1 00' MAXIMUM.
(C) IF APPROVED BY THE SOILS ENGINEER ANO/OR ENGINEERING GEOLOGIST.
WINDROWS MAY BE PLACED DIRECTLY ON COMPETENT MATERIAL OR BEDROCK
PROVIDED ADEQUATE SPACE IS AVAILABLE FOR COMPACTION,
(D) ORIENTATION OF WINDROWS MAY VARY BUT SHOULD BE AS RECOMMENDED BY
THE SOILS ENGINEER ANDIOR ENGINEERING GEOLOGIST_ STAGGERING OF
WINDROWS IS NOT NECESSARY UNLESS RECOMMENDED.
(E) CLEAR AREA FOR UTILITY TRENCHES, FOUNDA T IONS AND SWIMMING POOLS.
(F) ALL FILL OVER AND AROUND ROCK WINDROW SHALL BE COMPACTED TO 90%
RELATIVE COMPACTION OR AS RECOMMENDED.
(0) AFTER FILL BETWEEN WINDROWS IS PLACED AND COMPACTED WITH THE LIFT OF
FILL COVERING WINDROW, WINDROW SHOULD BE PROOF ROLLED WITH A
0-9 DOZER OR EQUIVALENT.
VIEWS ARE DIAGRAMMATIC ONLY. ROC< SHOULD NOT TOUCH PLATE Rfl-
AND VOIDS SHOULD EE COMPLETE_'! FILE=D IN.
_ ROCK DISPOSAL PITS
VIEWS ARE DIALRAMMAIRC ONLY. ROCK SHOULD NOT TOUCH
ANO VOIDS SHOULD EF COMPLETELY FILLED IN.
FILL LIFTS COMPACTED OVER
ROCK AFTER EMEEDMENT -
GRANULAR MATERIAL
- I
- - - LARGE ROCK --- - -�
I t
- I I
COMPACTED FILL I
t SIZE OF EXCAVATION TO BE I
I COMMENSURATE WITH ROCK SIZE I
t I
I l
ROCK DISPOSAL LAYERS
GRANULAR SOIL TO FILL VOIDS, / COMPACTED FILL
DENSIRED BY FLOOCING
I
LAYER ONE ROCK HIGH
PROPOSED FINISH GRADE PROFILE ALONG LAYER
TO' MINIMUM OR BELOW LOWEST UTILIT
--- - - - - -- - - -- - -� 20' MUM
OVERSIZE LAYER
`\ FR LOPE FACE
COMPACTED FILL
13- MINIMUM
FILL SLOPE
CLEAR ZONE 20' MINIMUM
LAYER ONE ROCK HIGH
TOP VIEW PLATE RD-2