1989-9050 C/G/H/J/R/U/V
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SOIL AND GEOLOGIC INVESTIGATION
FOR
LONE JACK ROAD PROPERTY
ENCINITAS, CALIFORNIA
FOR
BARRATT OF SAN DIEGO
SAN DIEGO, CALIFORNIA
BY
GEOCON INCORPORATED
SAN DIEGO, CALIFORNIA
NOVEMBER 1987
.'mfn)
fEB I o~~
CITY OF ENCINITAS
OEflLQ.F PUBLIC WORKS
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GEOCON
I N COR P 0 RAT E U
~
Geotechnical Engineers and
Engineering Geologists
File No. D-3983-M02
November 30, 1987
Barratt of San Diego
3615 Kearny Villa Road, Suite
San Diego, California 92123
101
Attention:
Mr. Jim Devlin
Subject:
LONE JACK ROAD PROPERTY
ENCINITAS, CALIFORNIA
SOIL AND GEOLOGIC INVESTIGATION
Gentlemen:
In accordance with your authorization and our proposal dated October 23,
1987, we have performed a soil and geologic investigation for the subject
project. The accompanying report presents the findings of our study
relative to the geotechnical engineering aspects of developing the project
as presently proposed.
If there are any questions or if we can be of further service, please
contact the undersigned at your convenience.
Very truly yours,
d~~
RCE 20427
..
Michael W. Hart
CEG 706
EHP:TVL:MWH:bmc
(3) addressee
9530 Dowdy Drive
San Diego, CA 92126
619695-2880
~~-j:'~
E11z~beth Herbert-Pischke
Staff Geologist
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TABLE OF CONTENTS
GEOTECHNICAL ENGINEERING INVESTIGATION
Page
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Purpose and Scope ....
General Site Conditions. . .
Site and Geologic Conditions
Alluvium (Qal) . . .
Topsoils (unmapped). . .
Colluvium (unmapped) . .
Santiago Peak Volcanics.
Landslides .
Groundwater. . . . . . .
Rippability. . . . . . .
Faulting and Seismicity.
Liquefaction. . . . . ..
1
2
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3
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4
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5
5
5
6
CONCLUSIONS AND RECOMMENDATIONS
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General. . . . . . . . . .
Potential Geologic Hazards
Groundwater. . . . . . . .
Soil and Excavation Characteristics.
Slopes . . .
Grading. . . . . . . . . . . . . .
Foundations. . . . . . . . . . . .
Retaining Walls and Lateral Loads.
Drainage and Maintenance
Grading Plan Review. . . . . . . .
7
8
9
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10
12
14
16
18
18
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LIMITATIONS AND UNIFORMITY OF CONDITIONS
Figure I, Site Plan
Figure 2, Major Earthquake Map
Figure 3, Stability Calculations For Cut Slope
Figure 4, Surficial Slope Stability Fill Analysis
APPENDIX A
FIELD INVESTIGATION
Figures A-I - A-II, Logs of Test Trenches
APPENDIX B
LABORATORY TESTING
Table I, Summary of Remolded Direct Shear Test Results
Table II, Summary of Laboratory Compaction Test Results
Table III, Summary of Expansion Index Test Results
APPENDIX C
RECOMMENDED GRADING SPECIFICATIONS
Figure C-l, Typical Benching Detail
Figure C-2, Recommended Canyon Subdrain Detail
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File No. D-3983-M02
November 30, 1987
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SOILS AND GEOLOGIC INVESTIGATION
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Purnose and Scone
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The purpose of our investigation was to observe and sample the prevailing
surface and subsurface soil and geologic conditions at the site in order
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to provide recommendations relative to geotechnical aspects of the
proposed site development (Figure 1).
Aspects of site development which
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were to be addressed included supplemental rippability information
preliminary foundation design criteria, and grading specifications. The
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"Vesting Tentative Map" supplied by San Dieguito Engineering and dated
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July 31, 1987 does not show final pad elevations.
It is assumed that the
estate-sized lots will be graded to receive single-family residences and
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that maximum cut and fill slopes will not exceed 25 feet in height.
Geocon Incorporated should be informed of any changes contemplated to be
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the above map.
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The scope of this investigation included a geologic reconnaissar.ce by our
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engineering geologist and the excavation of 22 exploratory trenches.
Trench Logs 1 through 9 are presented in our Report of Rippability
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Investigation dated October 15, 1987. Details of the field investigation
are presented in Appendix A.
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Laboratory tests were performed on selected samples obtained from the
trenches to determine pertinent physical characteristics of the soil types
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encountered.
A swnmary of the laboratory test results is presented in
Appendix B.
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General Site Conditions
The roughly L-shaped property is located east of Lone Jack Road and north
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of Dove Hollow Road in Encinitas, California (see Figure 1). The site is
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characterized by two northeast-southwest trending ridges traversing the
site with moderate to gentle slopes adjacent to a southwest trending main
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drainage.
Two side tributaries feed in from the northwest.
Elevations
range from approximately 770 feet MSL at the southwest corner of the site
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to approximately 1072 feet MSL at the northeast corner of the site. The
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subject property is surrounded on two sides by very low density rural
housing, with the north and east sides undeveloped.
Vegetation consists
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of chaparral and low brush on the hillsides, with grasses and deer brush
present in the broad swales and drainages.
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Site and Geolo~ic Conditions
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The site is underlain by Jurassic-aged Santiago Peak Volcanics which
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locally has been extremely weathered in scattered locations. Topsoils and
colluvium are present on the tops and sides of the hills.
Alluvium was
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encountered in the drainages.
Each of the soil types is discussed below
in order of increasing age.
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File No. D-3983-M02
November 30, 1987
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Alluvium (Oal). Trench No. 30 encountered a 4 foot layer of alluvium
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although the average thickness was typically approximately 2 to 3 feet.
The alluvium generally consisted of brown to reddish-brown, silty-clayey,
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fine to coarse sand overlying brown, clayey gravel.
The materials will
require removal and recompaction prior to the placement of fill along the
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drainages.
Such removals may be complicated by subsurface seepage along
bedrock fractures.
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Tonsoils (unmanned).
The topsoils developed on top of the hills
underlain by resistant Santiago Peak Volcanics averaged 2 to 3 feet in
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thickness and generally consisted of very stiff, reddish brown, sandy
clay.
Trench No. 26 encountered 5 feet of topsoil.
These materials
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generally possess moderate to high expansive potential.
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Colluvium (unmanned).
Soft to stiff, reddish brown to brown, sandy
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clays comprise the colluvium deposited on the highly weathered older
bedrock in the lower elevations. The colluvium averaged 2 to 3 feet thick
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as encountered in the trenches and reached a maximum thickness of 5 feet
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as observed in Trench No. 14. Colluvium 4 feet thick was noted in Trench
No. 18.
It is our opinion that the unusual thickness of colluvium
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represents movement by gravity of extensively weathered Santiago Peak
Volcanics. North-facing slopes appear to have developed a greater than
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average thickness of colluvium.
Due to the potential for shallo", soil
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failure, removal and recompaction is recommended for colluvial soils where
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they will exist beneath proposed fills or in cut slopes.
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Santiago Peak Volcanics (Jsp). The
ridges were composed of
moderately to very weathered metavolcanics.
Highly weathered Santiago
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Peak metavolcanics were encountered in several of the trenches, especially
on the north-facing slopes.
Trench No. 18 was excavated to 8 feet below
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the present surface and contained 4 feet of stiff, gray-green mottled red
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and white, sandy clay.
The mottled color is an indication both of
substantial amounts of clay and of past standing water conditions. The
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results of the "Rippability Investigation for Lone Jack Road Property" by
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Geocon Incorporated and dated October 15, 1987 indicate that the Santiago
Peak Volcanics with overlying topsoils and colluvium can generally be
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excavated to an average depth of 6 to 7 feet using conventional mass
grading equipment.
Recommendations concerning excavation and subsequent
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blasting will follow in the "Conclusions and Recommendations" section of
this report.
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Landslides.
No landslide deposits were encountered during the
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investigation.
However, areas of thi'cker than average colluvium and
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topsoil may be prone to shallow slumping along the surficial soil/Santiago
Peak Volcanics contact in cut slopes due to the increase in watering that
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attends site development.
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Groundwater.
No seepage was encountered in any of the exploratory
trenches.
Due to the fractured nature of the rnetavolcanics, groundwater
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may be transmitted along joints leading to possible slope instability.
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Therefore, cut slopes should be observed by a representative of Geocon
Incorporated and possible mitigatory measures taken at that time.
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RiDDabilitv.
Based upon the results of the previously referenced
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"Seismic Investigation," blasting to achieve the proposed grades is likely
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where ever cuts exceed a depth of approximately 6 feet.
In addi tion,
grading operations may encounter resistant rock at or near the surface.
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Generally,
the velocities of the seismic
traverses suggest that
excavations in the Santiago Peak Volcanics can be accomplished with
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moderate to heavy effort to a depth of approximately 6 to 7 feet utilizing
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a D-9L with double-shank rippers.
Overexcavation during grading
operations in areas to receive utility trenches may be advantageous to
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facilitate trenching.
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Faulting and Seismicitv.
The present reconnaissance did not reveal
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any active faults traversing the subject site.
Figure 2 indicates the
locations of major earthquakes and recently active faults in Southern
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California.
The recent offshore seismic activity demonstrates that small
magnitude earthquakes can be generated by offshore faults.
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The closest active faults to the site are the Elsinore Fault, located
approximately 27 miles to the northeast and the offshore faults, located
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approximately 23 miles to the west. The probability of the San Diego area
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experiencing a locally generated Magnitude 6 or greater earthquake would
appear to be low based on present knowledge.
Earthquakes less than
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Magnitude 4 have been common in the San Diego region.
Such earthquakes
rarely result in significant damage to well built structures.
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Liauefaction.
The potential for liquefaction is relatively low, as
normal grading operations should increase the density of the alluvial and
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colluvial materials I and the distance of the site from active faults is
relatively large.
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CONCLUSIONS AND RECOMMENDATIONS
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General
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1. No soil or geologic conditions were encountered which would preclude
the development of the site as tentatively planned, provided the
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recommendations contained herein are followed.
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2.
The field investigation indicates that the site is underlain by
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alluvium, topsoil and colluvium, and dense to very dense metavolcanic
rock. The topsoil, colluvium and alluvium are not considered suitable for
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foundation support in their present condition and will require remedial
grading as described below.
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3. Based on the results of the previously referenced seismic refraction
study, augmented by the present study, it is our opinion that blasting is
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likely to be required during excavations of cuts deeper than approximately
6 feet below the present surface.
Blasting of utility lines may be
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required in deep cut areas as described in the text of this report.
It
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should be anticipated that localized blasting of near surface and surface
outcrops and isolated boulders could occur during mass grading or
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trenching operations.
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Potential Geologic Hazards
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4. No faults or indications of faults were mapped on the site during the
field investigation. However, the site could be subjected to moderate to
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severe ground shaking in the event of a major earthquake along any of the
active faults in the Southern California area. It is our opinion that the
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seismic risk at the site is not significantly different than that of the
surrounding area or the Encinitas area in general.
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5.
No landslides or indications of deep seated landslides were noted on
the
site.
It is our opinion that the potential for deep seated
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landsliding is very low and should not be a constraint to site
development.
However, slumping at the surficial soil/Santiago Peak
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Volcanic contact could occur in areas of greater than average thickness of
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topsoil and colluvium, especially in times of increased rainfall or heavy
irrigation.
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6.
The alluvial soils on site have a low potential for liquefaction
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because of the relatively long distance to an active or potentially active
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fault and because the alluvial deposits are not presently within the
influence of the permanent groundwater table.
In our opinion, the
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liquefaction potential of these soils will be further decreased after they
are excavated and recompacted as recommended under "Grading."
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Groundwater
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7. No groundwater was encountered during the present investigation;
however, water may perch on the surficial soil/Santiago Peak Volcanics
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contact. The perched groundwater is not expected to impact significantly
the stability of cut slopes in general, however, subsurface drainage
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measures may be required to intercept the water in some locations. Areas
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where such drains may be required will be determined in the field during
grading.
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Soil and Excavation Characteristics
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8. The soils on site vary from a highly expansive clayey surficial soils
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to low expansive metavolcanic rock in various stages of decomposition.
Highly weathered Santiago Peak Volcanics are moderately to highly
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expansive.
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9. In areas where blasting is required, we recommend a minimum 3-foot
excavation below finish grade where future footings or utilities are
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proposed.
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10. Oversize material (greater than 12 inches in size) can be expected to
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be generated during the grading operations and special handling of this
material will be required.
We recommend that these materials be placed,
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where possible, in accordance with the attached "Recommended Grading
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Specifications" (Appendix C).
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11. It should be anticipated that shallow excavations of less than 6 feet
in depth will generate oversize materials (greater than 12 inches in size)
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along with abundant clayey surficial soils.
The high clay content may
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make adherence to the grading specifications for placement of rockfills or
soil-rock fills impractical. Therefore the use of a rock-crusher may be
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required to manufacture acceptable fill materials.
In deeper cuts,
blasting techniques should be utilized that result in generation of rock
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no greater than 3 feet in maximum dimension with sufficient finer rock
sizes to fill voids between the larger rock as described under section 6.3
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of the grading specifications.
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Slopes
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12. It is our opinion, based on our experience and previous analyses,
that the proposed 2:0 to 1.0 inclined cut slopes made in Santiago Peak
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Volcanics are typically stable to the design heights of at least 25 feet.
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Tops of cut slopes should be cleared of loose boulders and should be
rounded within the exposed topsoil horizon.
If the topsoil horizon is
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sufficiently loose, overexcavation and recompaction of materials may be
required at the top of cut slopes.
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13. All cut slopes should be observed by an engineering geologist during
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grading to verify that geologic conditions do not differ significantly
from those anticipated.
If adverse conditions are encountered,
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recommendations for slope buttressing or other remedial measures can be
presented at that time.
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14.
Our
analyses, utilizing the results of direct shear tests on
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remolded samples, indicate that for design heights of approximately 25
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feet, 2.0 to 1.0 compacted fill slopes composed of granular metavolcanic
rock will have calculated factors of safety of at least 1.5 against both
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deep-seated and surficial slope failures (Figures 3 and 4). Fill slopes
shall be constructed of properly compacted material derived from on-site
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cutting operations.
Soils with high clay contents should not be used in
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the outer 10 feet of the face of slopes.
Deeper than normal "benching"
may be required to reach firm formational materials in areas where the
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Santiago Peak Volcanics have been deeply weathered.
Benches should be
made such that the surface being compacted is inclined into the slope.
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15. It is recommended that all fill slopes be compacted during grading
with a sheepsfoot roller at maximum 4-foot fill height intervals and
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trackwalked with a dozer upon completion.
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16.
All slopes should be planted, drained and properly maintained in
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order to help control erosion.
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Grading
17. All
grading
should be performed in accordance with the attached
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IIReconunended
Grading
Specifications"
(Appendix
C) .
Where
the
recommendations
of
this
section
conflict with Appendix
C,
the
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recommendations of this section take precedence.
All grading should be
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observed, by and all compacted fill tested by, representatives of Geocon,
Incorporated.
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18.
It is recommended that a preconstruction conference be held at the
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site with the owner or developer, grading contractor, civil engineer, and
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geotechnical engineer in attendance.
Special soil handling and/or the
grading plans can be discussed at that time.
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19.
The existing topsoil, colluvium, alluvium and very minor scattered
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end dump fills are not suitable for the support of fill or structural
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loads in their present condition.
It is recommended that all surficial
soils not removed by planned grading 'operations be excavated to firm
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natural ground and properly compacted to at least 90
percent relative
compaction.
Surficial soils on slopes and ridge tops
are expected to
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average 3 feet in depth.
Alluvium and colluvium in the drainages are
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estimated to average 3 to 5 feet in depth. The actual depths of removal
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will be determined during grading. All overexcavations should be observed
by a representative of Geocon Incorporated to verify that firm, natural
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ground has been attained.
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20.
Subdrains should be installed in the drainages to be filled.
A
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cross8section of the recommended subdrain configuration is presented in
Appendix G.
Location of the subdrains will be established when grading
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plans for Lone Jack Road Property are finalized.
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21. Undocumented end-dump fills of limited areal extent are present in
several locations on the site and should be removed and recornpacted.
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Abundant deleterious material may be encountered in the fill and should be
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removed and not used in the compacted fill.
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22. It is recommended that the cut portion of cut-fill transition lots be
undercut at least 3 feet so as to provide a building pad that is either
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entirely in cut or entirely in fill.
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23.
The upper 3 feet of fill in building pads and 12 inches in pavement
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areas should be composed of properly compacted, finish grade soils. If
expansive soils are encountered, they should be placed in the deeper fill
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areas and properly compacted.
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24.
Finish grade soils are defined as those soils that have an expansion
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index of 50 or less in accordance with UBC Standard 29-2.
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Foundations
25. The following foundation recommendations for the proposed one- and/or
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two-story residential structures are separated into categories dependent
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on the depth and geometry of underlying fill soils for a particular lot.
Determination of final foundation design for specific lots will be made at
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the completion of grading and will be presented at that time within
interim and/or final reports of mass grading operations. It should be
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noted that the following foundation recommendations pertain to lots
excavated in or capped with a minimum of 3 feet of "very low" to "lawll
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expansive soils (Expansion Index of 50 or less). For lots possessing an
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Expansion Index greater than 50 within 3 feet of finish grade, additional
recommendations will be provided.
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Categorv I: Shallow Fill and Cut Pads. In general, the lots
within this category include cut lots, undercut aad/or
transition cut lots with less than 10 feet of fill thickness
differential or fill lots underlain by less than approximately
20 feet of fill. Most pads are expected to fall in this
category.
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A.
It is recommended that foundations within this category
have a minimum depth of 12 inches and a minimum width of 12
inches. Foundations so proportioned may be designed for an
allowable soil bearing pressure of 2,000 psf (dead plus
live load). This bearing pressure may be increased by up
to one-third for transient loads such as wind or seismic
forces.
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B.
Continuous footings should be reinforced with two No. 4
reinforcing bars, one placed near the top of the footing
and one near the bottom.
C.
Concrete slabs-on-grade should have a thickness of 4 inches
and should be reinforced with 6x6-6/6 welded wire mesh
throughout. It has been our experience that the mesh must
be physically pulled up into the slab after the placement
of concrete. The mesh should be positioned within the
upper one-third of the slab. Proper mesh positioning is
critical to future performance of the slabs. The slab
should be underlain by at least 4 inches of clean sand and,
where moisture sensitive floor coverings are planned, a
visqueen moisture barrier covered by at least 1 inch of the
sand cushion should also be provided.
Categorv II: Medium Deep Fill Pads. In general, the lots within
this category are underlain by 20 to 50 feet of fill and have a
differential thickness of less than 10 feet.
A.
It is recommended that foundations within this zone have a
minimum depth of 18 inches and a minimum width of 12
inches. Foundations so proportioned may be designed for an
allowable soil bearing pressure of 2,000 psf (dead plus
live load). This bearing pressure may be increased by up
to one-third for transient loads such as wind or seismic
forces.
B.
Continuous footings should be reinforced with four No. 4
reinforcing bars, two placed near the top of the footing
and two near the bottom.
C.
Concrete slabs-on-grade should have a thickness of 4 inches
and should be reinforced with No. 3 reinforcing bars spaced
at 24 inches in both directions. The slab should be
underlain by at least 4 inches of clean sand and, where
moisture sensitive floor coverings are planned, a visqueen
moisture barrier covered by at least 1 inch of sand cushion
should also be provided.
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26. Footings located on or near the top of a slope are not recommended.
However, where such a condition cannot be avoided, the footing depth
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should be such that the bottom outside edge of the footing is at least 7
feet from the face of the slope.
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27. The
recommendations presented herein are intended to
reduce the
potential
for cracking of slabs and foundations as a
result of
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differential settlement of deep fills or fills of varying thicknesses.
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However I even with the incorporation of the reconunendations presented,
foundations and slabs-on-grade placed on such conditions may still exhibit
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some cracking.
The occurrence of concrete
shrinkage cracks is
independent of the supporting soil characteristics.
Their occurrence may
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be reduced and/or controlled by limiting the slump of the concrete, proper
concrete placement and curing, and by the placement of crack control
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joints at periodic intervals, and in particular, where re-entry slab
corners occur.
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Retaining Walls and Lateral Loads
28. Retaining walls not restrained from movement at the top and having a
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level backfill surface should be designed for an active soil pressure
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equivalent to the pressure exerted by a fluid weight of 30 pcf. Where the
backfill will be inclined at no steeper .than 2:1, an active soil pressure
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of 43 pcf is recommended.
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29.
Unrestrained walls are defined as those walls that are allowed to
rotate more then O.OOlH at the top of the wall.
Where walls are
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restrained from movement at the top, an additional uniform horizontal
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pressure of 7H psf (where H equals the height of the retaining portion of
the wall in feet) should be added to the above active soil pressure.
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30. All retaining walls should be provided with a drainage system
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adequate to prevent the buildup of hydrostatic forces and should be
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waterproofed as required by the Project Architect or Design Engineer. The
above recommendations assume a properly compacted granular backfill
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material with no hydrostatic forces or imposed surcharge loads. If
conditions different than those described are anticipated or if specific
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drainage details are desired, Geoeon Incorporated should be contacted for
additional recommendations.
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31. For resistance to lateral loads, we recommend a passive earth
pressure equivalent to a fluid weight of 300 pcf for footings or shear
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keys poured neat against undisturbed natural soils or properly compacted
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granular fill soils. This lateral pressure assumes a horizontal distance
for the soil mass extending at least 10 feet or three times the surface
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generating passive pressure, whichever is greater. The upper 12 inches of
material not protected by floor slabs or pavement should not be included
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in the design for lateral resistance.
If friction is to be used for
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lateral resistance, we recommend using a coefficient of 0.4 between the
soil and concrete.
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Draina~e and Maintenance
32. Good drainage is imperative to reduce the potential for differential
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soil movement, erosion and subsurface seepage. Positive measures should
be taken to properly finish grade the building pads after the structures
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and other improvements are in place, so that drainage water from the lots
I
and adjacent properties is directed off the lots and to the streets away
from foundations and the top of slopes.
Experience has shown that even
I
with these provisions, a shallow groundwater or subsurface water condition
can and may develop in areas where no such water conditions existed prior
I
to site development; this is particularly true where a substantial
I
increase in surface water infiltration results from an increase in
landscape irrigation.
I
Grading Plan Review
I
33. The soil engineer and engineering geologist should review the grading
I
plans prior to finalization to verify their compliance with the recommen-
dations of this report and determine the need for additional comments,
I
recommendations and/or analysis.
All recommended
buttress
fills
and
sub drains should be shown on the final grading plans.
I
I
-18-
I
I
I
File No. D-3983-M02
November 30, 1987
I
LIMITATIONS AND UNIFORMITY OF CONDITIONS
I
1.
The recommendations of this report pertain only to the site
I
investigated and are based upon the assumption that the soil conditions do
not deviate from those disclosed in the investigation. If any variations
I
or undesirable conditions are encountered during construction, or if the
proposed construction will differ from that anticipated herein, Geocon,
I
Incorporated should be notified so that supplemental recommendations can
be given.
I
I
2. This report is issued with the understanding that it is the
responsibility of the owner, or of his representative, to ensure that the
I
information and recommendations contained herein are brought to the
attention of the architect and engineer for the project and incorporated
I
into the plans, and the necessary steps are taken to see that the
I
contractor and subcontractors carry out such recommendations in the field.
I
3. The
findings of this report are valid as of the present date.
However,
changes in the conditions of a property can occur with the
I
passage of time, whether they be due to natural processes or the works of
I
man on this or adjacent properties. In addition, changes in applicable or
appropriate standards may occur, whether they result from legislation or
I
the broadening of knowledge. Accordingly, the findings of this report may
be invalidated wholly or partially by changes outside our control.
I
Therefore, this report is subject to review and should not be relied upon
after a period of three years.
I
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I File No. D-3983-M02
November 30, 1987
I
I
I
I
I
I
Stability Calculations For "Cut" Slopes
N C'
FS = et
yH
1. Find N cf
I
. ^c~ yH tan ~ ' Where Average wet density
= C' y =
of soil (pet)
Assume: y = 127 pet H = Slope height (feet)
H= 25 ft ~'= Angle of internal
~'= 0 friction (degrees)
32
C'= 350 psf C'= Apparent cohesion
(psf)
Then: ^c$ = 2') U2]) tan 30 0
350
I
I
I
I
I
I
I
I
I
I
^c~ = 5.7
Results of Direct Shear Tests
~ C'
35 380
From Janbu, Ncf = 22
2. Find FS
FS = 22 (,50 )
127 (2)
FS = 1. 89
Parameters Used
~ C'
32
350
Figure 3
I
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I
I
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I
I
I
I
I
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I
I
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I
File No. D-3983-M02
November 30, 1987
Figure 4
/' /" ~"
/.c.~""
ID ~ '(6~'t
...G",,,
'<-~\o
'"
ASSUMED PARAMETERS
2 = DEPTH OF SATURATION = 3 feet
= SLOPE ANGLE = 26.60
Ow = UNIT WEIGHT OF WATER = 62.4 pef
aT - . SATURATED UNIT WEIGHT OF SOIL = 127 pcf
Y:l = APPARENT ANGLE OF INTERNAL FRICTION = 320
C = APPARENT COHESION = 350 psf
FS = C . T TAN 0 = C. (OT - ow) 2 COS2 i TAN 0
T ~T 2SINiCOSi
FS = 350+(127-62.4) 3 COs2 26.6 TAN 32 446.8
=
127 (3) SIN 26.6 COS 26.6 152.5
FS = 2.93
SURFICIAL SLOPE STABILITY FILL ANALYSIS
LONE JACK ROAD PROPERTY
ENCINITAS, CALIFORNIA
I
I
I
I
I
I
I I
I
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APPENDIX A
I
I
File No. D-3983-M02
November 30, 1987
I
I
APPENDIX A
FIELD INVESTIGATION
I
I
The field investigation was performed on October 23 and October 26, 1987
and consisted of a site reconnaissance by an engineering geologist and the
I
excavation of 22 exploratory trenches.
The trenches were advanced to
depths ranging from 2 to approximately 9 feet using a John Deere 555
I
trackhoe with a 24 inch wide bucket.
The approximate locations of the
I
excavations are shown on Figure 1.
As trenching proceeded, the soils
encountered were continuously observed, visually classified and logged.
I
Logs of the test trenches are included herein.
The logs depict the
various soil types encountered and indicate the depths at which bulk and
I
relatively undisturbed chunk samples were obtained.
I
I
I
I
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I
I
I
I
I
File No. D-3983-M02
November 3D, 1987
I
fz:U
w-w
c "
o
z
~
~
~
:i
>
8
~
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"
~
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- TlO-2
- 2-
-
'/...o~:
....
-
101 IA
,.1 I
,
I I I
, IY'O
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-
- 4
-
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-
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l-
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-
-
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o
Tll-l ~.'."
- Tll-2 ~/
_ 2. ..'
Tl1-3 ~ "0
~ 4: I ~&i
- ~::.
- 6.
-
- -
I- -
I- -
I- -
I I- -
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- .
-
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w
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Q
Z
~
if
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m
~;;
~u
u'"
=::i
o-
m
TRENCH 10
ELEVATION
EQUIPMENT
814
JD 555
10/23/87
----
DATE DRILLED
MATERIAL DESCRIPTION
TOPSOIL
Very stiff,
CLAY
cobbles
\
\
\
'---
\
SANTIAGO PEAK VOLCANICS
Very dense, humid, light
GRAVEL
moist, reddish-brown, Sandy
green, Silty
TRENCH TERMINATED AT 4.0 FEET
TRENCH 11
COLLUVIUM
Stiff, slightly
CLAY with trace
texture
EL. 821
moist, reddish-brown, Sandy
gravel, slightly porous
\ SANTIAGO PEAK VOLCANICS
Very dense, humid, light gray-green,
\ Clayey GRAVEL
L-..
Very dense, humid, light gray, Silty
GRAVEL, jointed with clay along joints
I
TRENCH TERMINATED AT 5.0 FEET
Figure A-l, Log of Test Trenches 10 and 11
l-
I-
-
-
-
-
I-
-
-
-
l-
I-
l-
I-
-
-
-
::it
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<m
~~
m~
~m
~
;;;
Z~
Wu
c~
>
"
c
w'
"0"
~z
"W
!:2z
~8
BULK
AMPLE
BULK
Al1PLE
I
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
~ _ DISTURBED OR BAG SAMPLE
I)_STANDARD PENETRATION TEST
iJ_ CHUNK SAMPLE
. _ DRIVE SAMPLE (UNDISTURBED)
~ __ WATER TABLE OR SEEPAGE
I
NOTE THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPL1ES QNL Y ATTHESPECIFICBORINGORTRENCH LOCATION AND
AT THE DATE INDICA TED_IT IS NOTWARRANTED TO BE REPRESE NT AliVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
I
File No.
November
D-3983-H02
30, 1987
I
o
z
w
-
~
,
~
>
8
-
o
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- -
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T13-1 110.,'/,'
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- 00
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- .
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-
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.
-
~
w
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If
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TRENCH 12
~
~-
<'"
-0
u'"
=:i
g-
DATE DRILLED
10 /22 /87
ELEVATION 805
EQUIPMENT JD 555
MATERIAL DESCRIPTION
COLLUVIUM
\~Oft, slightly moist, brown, Sandy CLAY
Stiff, moist, dark reddish-brown, Sandy
CLAY with trace gravel
SANTIAGO PEAK VOLCANICS
\ Very dense, humid, gray-blue-green,
Clayey GRAVEL
L-
Very dense, humid, gray-green, Silty
GRAVEL with clay along joints
TRENCH TERHINATED AT 4.0 FEET
EL. 836
--~,
\
TRENCH 13
COLLUVIUH
Firm, moist, reddish-brown, Sandy CLAY
Stiff, moist, orange-brown, Sandy CLAY
with trace of gravel
\ SANTIAGO PEAK VOLCAN~CS
\ Stiff, moist, gray-green,
with some gravel
I
Sandy C~AY
Very dense, humid, dark blue, Clayey
GRAVEL
TRENCH TERHINATED AT 6.5 FEET
I Figure A-2, Log of Test Trenches 12 and 13
-
-
-
-
-
~
I-
-
-
-
-
-
-
l-
I-
-
Zw
g~t
<<"'
~:;;~
~;)g
~~Gl
~
in
z~
W0
o~
>
~
o
6
0-'
Z
w
-
z
8
BULK A1lPLE
BULK A11PLE
I
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
l8J _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
"_CHUNK SAMPLE
. _ DRive SAMPLE (UNDISTURBED)
~ _.. WATER TABLE OR SEEPAGE
I
NOTe THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFICBOAING QRTRENCH LOCATION AND
AT THE DATE INDICA TED_ IT IS NOT WARRANTED TO BE REPRESENT A live OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TI MES.
I
I
File No. D-3983-H02
November 30, 1987
I
" TRENCH 14
0 > w ~ Zw ~
Z 8 ~ ~- g~~ #
z ~ ~" ~ "'
.zw w ~ 0 ~" 817 10/23/87 ~~~ Z~ Z
~ 0 u" ELEVATION DATE DRILLED
w-w ~ Z !:t;;5: w0 w
o " . z " :;j o~ ~
;\ ~ ~ g- ~c;;g > Z
~ JD 555 ~~a:l " 8
0 EQUIPMENT 0
MATERIAL DESCRIPTION
0 ,.: COLLUVIUH
:-/
Tl4-1 V. -- "\ So f t , moist, dark brown, very Sandy CLAY
.. .
2 . V
. . .. L
. . .'. -
... 4 . "<"-::'.:". Firm, slightly moist, brm;m, very Sandy -
;/ CLAY with
trace of gravel
... . . "." -
9(,
- 6 . ' . .
I I I SANTIAGO PEAK VOLCANICS
- . 1';1 :r, Gery stiff, slightly moist. red and I-
... 8 " I green, very Gravelly CLAY; weathered I-
... - Very dense, humid, blue, Silty GRAVEL I-
... -
- -
TRENCH TERHINATED AT 8.0 FEET
- -
~ . -
t- . -
0 TRENCH 15 EL. 895
- ~;J;f ---- , TOPSOIL -
Tl5-1 ...... \ Hard, slightly moist, reddish-brown, Sandy
.' . ". ~
_ 2 _ /V . \ CLAY with gravel -
I
v 00/ '-_ becomes brown-red with much clay,
- / blocky ...
.0// A
4 _ ;/ '" ~ /' SANTIAGO PEAK VOLCANICS
- - Very dense, humid. and blue. I-
gray-green
_ 6 _ Clayey GRAVEL -
- .
- .
"-
TRENCH TERHINATED AT 4.5 FEET -
-
... . , -
- . -
- -
I
I
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I
I
I
I
I
I
I
I
I
I
I
Figure A-3, Log of Test Trenches 14 and 15
I
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
[g'J _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
~ _ CHUNK SAMPLE
. _ DRIVE SAMPLE (UNDISTURBED)
~ _ WATER TABLE OR SEEPAGE
I
NOTE THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BORING ORTRENCH lOCATION AND
AT THE DATE INDICATED IT IS NOT WARRANTED TO BE REPRESE NTA nVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TI MES
I
I
File No. D-3983-M02
November 30, 1987
I
~ TRENCH 16
d > w ~ Zw ~
z 8 ~ ~;;; Qut:: w8
z ~ w ~d ~~(;j " ~>'
!;:zw ~ <5 u'" ELEVATION 923 DATE DRILLED 1O/71/R7 z" "z
w-w ~ z ~~~ Wd ~w
c ~ , z " =:j c~ !!?!Z
~ 1/ g-
~ " JD 555 z"" > ~8
" EQUIPMENT ww~ ~
~~ c
MATERIAL DESCRIPTION
0 /.. TOPSOIL
. - I :y Soft, humid, dark brown. very Sandy CLAY -
I
2. Tl6-1 .I.I; L- -
-
1'11'
- - ~o~ L:rd, humid, orange-brown, Silty CLAY I-
T16-2 BULK AMPLE
I- 4 I-
- - Very hard, humid, brownish-red, Clayey, l-
I- 0 fine to coarse SAND
I- 0 SANTIAGO PEAK VOLCANICS l-
Very dense, humid, gray-green and orange,
I- 0 Silty GRAVEL with clay seams
~
I- - TRENCH TERMINATED AT 4.0 FEET
-
-
0 -
TRENCH 17 EL. 870
- 0 1'l7-1 ~ COLLUVIUM
- 0 Tl7-2 Very stiff, humid, reddish-brown, very - BULK AMPLE
. .' . ,
- 2 . Sandy CLAY with some silt -
. " ,
- . :...:/ 1\/ gravel -
v//
- 4 . /{ 0
, . SANTIAGO PEAK VOLCANICS
.~ '
- Very dense, humid, i blue and orange, I-
- 6 - Clayey GRAVEL -
- - '"
I- 0
TRENCH TERMINATED AT 5.0 FEET
l- .
I- 0
~ 0
l- ..
l-
I- 0 -
I
I
I
I
I
I
I
I
I
I
I
I
I
I Figure A-4, Log of Test Trenches 16 and 17
I
SAMPLE SYMBOLS
0_ SAMPLING UNsuCCESSFUL
~ _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
~_CHUNKSAMPLE
. _ DRIVE SAMPLE (UNDISTURBEDI
~ _ WATER TABLE OR SEEPAGE
I
NOTE THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONL Y ATTHE SPECIFIC BOAING ORTRENCH LOCATION AND
AT THE DATE INDICA TED. IT IS NOTWARAANTED TO BE REPRESENT AliVE Of SUBSURFACE CONDITIONS AT OTHER lOCATIONS AND TI ME5.
I
I
File No. D-3983-H02
November 30, 1987
I
" TRENCH 18
6 > w ~ ~
z 8 ~ ~- ~t w~
~"
z ~ ~ ~ G0. z, ~ "",
tzw 799 10/23/87 ~~ z~ :>z
w-w . 0 z ~" ELEVATION DATE DRILLED w<j ~w
c " , z :> g2 "'0 c. ~!t
~ ~
~ ~ ~~ > ~8
JD 555 ~m "
0 EQUIPMENT 0
MATERIAL DESCRIPTION
~ 0 COLLUVIUM
' , --I
~ - II.v Firm, slightly moist, dark brown, Sandy
2 ./1\ ~L-:LAY with silt -
TlS-l " , ,
.. 102.S 19.5
- \~rm, moist, reddish-bro,m, Sandy CLAY -
TlS-2 /. BULK AMPLE
4 - ' ,". with silt -
, ~ ~ . \ Stiff, very moist, dark brown,
- TlS-3 ;; Gravelly - 112.0 16.6
TIS-4 Jo- .. BULK AHPLE
6 - '," .( ~LAY -
[/.,.<'
- .L.i0 Stiff, very mo is t , brown , Sandy CLAY -
'~'.''''D ----
- 8 . . ~ .
1 SANTIAGO PEAK VOLCANICS
. - I Stiff, moist, gray-green mottled with -
1
- - I red and white, Sandy CLAY with trace -
I pebbles -
- - I
- I l' :!: -
'--- cobbles to
- . TRENCH TERMINATED AT S.O FEET
- .
- .
-
0 TRENCH 19 EL. S07
- ~. COLLUVIUM
- - 0/ Firm, slightly moist to moist, brownish-
- 2 _ red, very Gravelly CLAY -
\ I
:/'
,. . .
- - ',.' ", -
- 4 O~ 0. Stiff, very moist, brown, Sandy CLAY -
\ with trace of gravel
- -
SANTIAGO PEAK VOLCANICS
- - Very dense, humid, blue and orange, -
- - large, Clayey GRAVEL -
- - -
- - "
TRENCH TERMINATED AT 4.0 FEET
- - -
- - -
I
I
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I
I
I
I
I
I
I
I
I
I
I
Figure A-5, Log of Test Trenches 18 and 19
I
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
~ _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
~_CHUNK SAMPLE
. _ DRivE SAMPLE (UNDISTURBED)
~ _ WATER TABLE OR SEEPAGE
I
NOTE THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BOFIING ORTRENCH LOCATION AND
ATTHE DATE INDICATED. IT IS NOT WARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER lOC" nONS AND TIMES
I
File No. D-3983-M02
November 30, 1987
I
I
~ TRENCH 20
6 > ~ 0 5W' ~
z 8 0_ #
r ~ .~ _ut in. '"
w ~ ~" 870 10/23/87 ~~ii5
~zw ~ u~ ELEVATION DATE DRILLED Z~ z
w-w ~ 0 z ~~~ w" w
" ~ , jE ~ =!:i ,,~ ~
~ :; ~- Z0~ > z
JD 555 ~~1O ~ 8
" EQUIPMENT 0
MATERIAL DESCRIPTION
0 /1 I I COLLUVIUM
. I I I \ Firm, humid, reddish-brown, Silty CLAY
-/-
- 2 . T20-1 ~-.Y_: ~th trace sand -
. .' .,' -
- Hard, humid, brownish-red, Sandy CLAY
-J11 - with trace gravel
- 4 ..",' .' -
~ SANTIAGO PEAK VOLCANICS
- .
- . ~rm, very moist, olive, Sandy CLAY -
- . -
- . Very firm, slightly moist, olive to -
- . light blue, Sandy SILT with some clay -
- - -
- -
- . TRENCH TERMINATED AT 4.0 FEET I-
- - -
- . -
- 0 TRENCH 21 EL. 991
l/f f TOPSOIL
- . ~. C2, Firm, humid, reddish-brown, Silty CLAY I-
T21-1
- 2 - with trace sand I-
~ v / /I
- . \
SANTIAGO PEAK VOLCANICS
- 4 . Very dense, damp, ,red and blue, Clayey .
- - BOULDERS
r- .
- -
TRENCH TEP~INATED AT 2.5 FEET
- .
- .
- . -
- . ,
-
- . -
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Figure A-6, Log of Test Trenches 20 and 21
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SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
~ _ DISTURBEOQR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
~_CHUNK SAMPLE
. _ DRIVE SAMPLE (UNDISTURBEDI
~ _ WATER TABLE OR SEEPAGE
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NOTE THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONl Y ATTME SPECIFIC BORING OATRENCH lOCATlONAND
AT THE DATE INDICATED, IT IS NOTWAARANTED TO BE REPRESENT AliVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
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File No. D-3983-1102
November 30, 1987
I
. TRENCH 22
d ~ w ~ Zw ~
8 ~ ~- w#
. ~ Z C~ Qut
w ~" <;;. ~~
kzw " 6 0 u'" ELEVATION lO?? DATE DRILLED 10/23/87 ~~ifj n
w-w ~ z ~!a~ w" ~w
o ~ , i" ~ =:) o. ~~
~ " g- z~~ ~ ~8
0 EQUIPMENT JD 555 ~~m .
0
MATERIAL DESCRIPTION
0 /
. . " TOPSOIL
.....
- '. \ Firm, humid, reddish-brown , Sandy CLAY -
2 - ....7:;.'. L- i-
..0 Stiff, humid, reddish-brown , Sandy CLAY
- ~" 0/ ~ with gravel
'oj'. ---
. 4 \
SANTIAGO PEAK VOLCANICS
. - \ Very dense, humid,
I reddish-brown and
- . I blue, Clayey GRAVEL and BOULDERS.
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- . L_ joints: N5E75S
- .
TRENCH TERHINATED AT 4.0 FEET
- - -
- - -
- - -
TRENCH 23 EL. 898
- 0 /.": COLLUVIUM
- - Firm, humid, dark sli~htly reddish-brown, -
'Z.'
'. '.' ~andY CLAY
- 2 - . . ,". . -
'/ .
- - O~ -
, /. Stif f , humid, reddish-brown, fine to
- 4 coarse, Sandy CLAY -
- -
SANTIAGO PEAK VOLCANICS
- - Very dense, damp, light gray-green, ..
t- o Clayey GRAVEL -
,
.
.
. TRENCH TERMINATED AT 4.0 FEET
- .
.
- - -
- -
. - .' -
- - -
- - -
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Figure A-7, Log of Test Trenches 22 and 23
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
~ _ DISTURBED OR BAG SAMPLE
[]_STANOARO PENETRATION TEST
Iii;] _ CHUNK SAMPLE
. _ DRIVE SAMPLE IUNOISTUABEOI
; _ WATER TABLE OR SEEPAGE
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NOTE: THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES QNL V A TTHE SPECIFIC BORING OR TRE NeM LOCATION AND
ATTHE DATE INDICATED IT IS NOTWARRANTEOTOBE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER lOCATIONS AND TIMES.
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File No. D-3983-M02
November 30, 1987
I
" TRENCH 24
d > w '" ~
8 ~ "'- w#
z <'" t
z ~ w ~0 10/26/87 in ",",
~zw ~ 876 ~ zw ~z
~ 0 u" ELEVATION DATE DRILLED
w-w ~ z ~ wu t1?~
o ~ , z ~ ='::i o.
~ ~ g- o OZ
~ " JD 555 ~ > '8
0 EQUIPMENT '" "
0
MATERIAL DESCRIPTION
f- 0 / I}, COLLUVIUH
f- - Firm, slightly moist, mottled orange and -
2 - f/' ( \ brown, Clayey SILT with minor fine sand I-
- .0>/
'/ SANTIAGO PEAK VOLCANICS
0/ ----
4 - , / Very dense, humid, orange and gray, Clayey
,/ ; I
o ~ \ BOULDERS
\
\
- 6 - L_ becomes less bouldery
- -
- . TRENCH TERHINATED AT 5.0 FEET -
- . -
- . -
TRENCH 25 EL. 869
- 0 COLLUVIUM
- - v all Firm, slightly moist, orange-brown, -
. / 0
- 2 - 0/ > Clayey SILT with trace medium sand -
- , ~..//
SANTIAGO PEAK VOLCANICS
- 4 - Very dense, damp, orange and blue, -
- - Clayey GRAVEL -
- -
TRENCH TERHINATED AT 3.0 FEET
- - -
. , -
.
- -
- -
- - -
- -
- - .- -
- - -
- - -
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Figure A-8, Log of Test Trenches 24 and 25
SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL.
C!?J _ DISTURBED OR BAG SAMPLE
ll_STANDARD PENETRATION TEST
IiiiJ _ CHUNK SAMPLE
. _ DAIVE SAMPLE (UNDISTURBED)
~ __ WATER TABLE OR SEEPAGE
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NOTE: THE lOG OF 5ueSUAFACECONOtTlDNS SHOWN HEREON APPLIES QNL. Y ATTHE SPECIFICBOAING QRTRENCH LOCATION AND
ATTHE DATE INDICATED. IT IS NOTWARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CON01TlONS AT OTHER LOCATIONS AND TIMES.
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File No. D-3983-M02
November 30, 1987
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I
~ TRENCH 26
" ~ w '" ~
z 8 ~ "'- w#
<'"
z ~ w ~o 0; ~'"
tzw ~ C 956 10/20/87 z~ ~z
~ C "", ELEVATION DATE DRILLED
w-w . z wo ~w
c " , ;: ~ :::!::i Co: "'~
~ ~ ~ g- ~ i5z
JD 555 ~ '8
c EQUIPMENT c
MATERIAL DESCRIPTION
0 26-1 w.;,'.
.- TOPSOIL 111.8 8.4
- f26-2 /: \ Firm, slightly moist, I-
- dark reddish-brown, ULK AMPLE
"." ,". Sandy CLAY with roots
2- . . .. I-
- "26-3 L
V 17.0 10.9
- .. I-
"26-4 . ., Very stiff, slightly moist, ULK AllPLE
- 4- . .. reddish-brown ,
Sandy CLAY with trace cobbles
- - F.?:' \
- 6 -
. I SANTIAGO PEAK VOLCANICS
- - O. /
/ \ Very dense, humid, gray and orange,
1/
- 8- // 0 Clayey, fine to coarse SAND with trace gravel
, L-
- -
- 10 - Very dense, damp, gray, Clayey GRAVEL -
- - -
- -
TRENCH TERMINATED AT 8.5 FEET
l- . -
... . -
... . -
0 TRENCH 27 EL. 995
1/1 II TOPSOIL
'/ \ Firm, humid, dark reddish-brown, Clayey -
2 _ ~ILT with roots ~
a ,/~
Hard, humid, reddish-brown, Sandy CLAY ...
,
_ 4 _ with trace boulders I-
-
SANTIAGO PEAK VOLCANICS
- - Very dense, damp, orange and gray, Clayey I-
- GRAVEL and BOULDERS
- -
-
TRENCH TERMINATED AT 3.0 FEET
- - "
- -
- - -
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I Figure A-9, Log of Test Trenches 26 and 27
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SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
~ _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TeST
~ _ CHUNK SAMPLE
. _ DAIVE SAMPLE {UNDISTURBEDI
~ _.. WATER TABLE OR SEEPAGE
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NOTE THE lOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES ONLY ATTHE SPECIFIC BORING QRTRENCH lOCATION AND
AT THE DATE INDICATED. IT IS NOTWAI=lRANTED TO BE REPRESENT AliVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES.
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File No. D-3983-H02
November 30, 1987
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0 TRENCH 28
0 > w ~ Zw
8 " ~- ~ w'
Z ~ <~ Qut;::
, " w ~" :;:~in '" Ow
~zw ~ 5 0 u~ ELEVATION q17 DATE DRILLED 10 /26/87 b =>z
w-w . z ~;~ w" "w
o w ~ , => =:::i o~ ~"
" ~ g- 5z
~ " JD 555 z~~ >
0 EQUIPMENT ~~CD " ~8
0
MATERIAL DESCRIPTION
0 I' COLLUVIill'1
. T28-1 ~v . Firm, humid, dark reddish-brown, Clayey
. ....:~
.. ....
2 0;'/ SILT
/
- , 00 \ SANTIAGO PEAK VOLCANICS
/
4 /. Very firm, humid, brown , Sandy CLAY .
/
~ / ~ith trace to some gravel 0
0 /
- 6 . / -
- . Very dense, humid, orange and olive, ..
Clayey GRAVEL
- . I-
- 0 TRENCH TEPJ1INATED AT 6.0 FEET
- 0 I-
- 0 I-
- .
_ 0 TRENCH 29 EL. 900
T29-1 <r .. ALLUVlUH BULK ~AMPLE
- Od Medium dense to dense, moist, dark brown,
- 2 0 /0 Clayey, fine to coarse SAND with minor
/ ~ravel
- v 0,/ 0
/
/ .
- 4 - 00/ Dense, humid, brown, Clayey GRAVEL with 0
/, II,
^ some fine to coarse sand
-
6 0 SANTIAGO PEAK VOLCANICS -
l- Very dense, humid, orange-tan, Clayey
i- 0 GRAVEL -
i- 0 ~
I- -
i- - TRENCH TElmINATED AT 5.0 FEET l-
i- 0 l-
I- 0 l-
I- 0 " l-
I- 0
i- -
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Figure A-10, Log of Test Trenches 28 and 29
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SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSF"Ul
~ _ DISTURBED OR BAG SAMPLE
IJ_STANDAAD PENETRATION TEST
iJ _ CHUNK SAMPLE
. _ CAlVE SAMPLE (UNDISTURBED)
~ _ WATER TABLE OR SEEPAGE
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NOTE: THE L.OG OF SUBSUAFACECONDITlONS SHOWN HEREON APPLIES ONL. Y ATTHE $PECtFICBOAING QRTRENCH LOCATION AND
A TTHE DATE INDICA TED. IT IS NQTWARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDITIONS AT OTHER LOCATIONS AND TIMES
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File No. D-3983-M02
November 30, 1987
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" TRENCH 30
0 > w ~ ~
z 8 ~ ~- w, w#
. <~ '-'t
t:ztij w ~ ~e> 854 10/26/87 ~;;, in "",
~ 0 z '-'~ ELEVATION DATE DRILLED z~ =>z
w-w . :;;~ we> t5~
c " , . => =::i c~
~ 2 ~- -0 OZ
;\ ~ 555 ~" >
~ EQUIPMENT JD ~. " '8
c
MATERIAL DESCRIPTION
- 0 <I}'> ALLUVIUM
- - Interbedded layers of medium dense, -
r- 2 . ',':'.;/ \ slightly moist, brown, Silty, fine to -
'./., . --- l;dium SAND and soft, humid, tan, slightly
t- o I:~(~q~':..'. \ Sandy SILT I-
4 - 1;:1.',,': :/, \ Dense, humid, brown, Clayey,
" \ coarse to
l ,7 \ fine SAND
- \
I.... j L
6 becomes very gravelly
.
SANTIAGO PEAK VOLCANICS
- . Very hard, damp, light green, Sandy SILT -
- . with trace gravel
- 0
- -
TRENCH TEPJ1INATED AT 6.0 FEET
- - -
l- . l-
I- I-
0 TRENCH 31 EL. 878
I-
T31-1 1,1: ALLUVIUM 97.1 15.5
I- ,',1.',1/ Medium dense, moist, reddish-brown , Clayey, I-
T31-2 ~r BULK AMPLE
I- 2. Silty, fine to coarse SAND with trace I-
,e,;<'.r:'. .- gravel
l- I : !/ I-
4 _ rz Soft, saturated, dark brown, Silty CLAY
,~.;O' I
--- 1\ with trace gravel
- I
6 _ \ SANTIAGO PEAK VOLCANICS
I Firm, moist, orange-brown, Sandy CLAY
- . \
\
- L_ becomes very gravelly
- -
TRENCH TERHINATED AT 5.0 FEET
- . -
- . .' -
- . -
- . -
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Figure A-II, Log of Test Trenches 30 and 31
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SAMPLE SYMBOLS
0_ SAMPLING UNSUCCESSFUL
[gJ _ DISTURBED OR BAG SAMPLE
IJ_STANDARD PENETRATION TEST
~ _ CHUNK SAMPLE
. _ DRIVE SAMPLE {UNDISTURBED}
~ __ WATER TABLE OR SEEPAGE
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NOTE. THE LOG OF SUBSURFACE CONDITIONS SHOWN HEREON APPLIES QNl Y ATTHE SPECIFIC BORING ORTRENCH LOCATION AND
ATTHE DATE INDICATED. IT IS NOTWARRANTED TO BE REPRESENTATIVE OF SUBSURFACE CONDlTlONS ATOTHER LOCATIONS AND TIMES
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APPENDIX B
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File No. D-3983-M02
November 3D, 1987
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APPENDIX B
LABORATORY TESTING
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Laboratory tests were performed in accordance with generally accepted test
methods of the American Society for Testing and Materials (ASTM) or other
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suggested procedures.
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Selected relatively undisturbed chunk samples were tested for their in-
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place dry density and moisture content.
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The maximum dry density and optimum moisture content of selected disturbed
bulk samples were determined in accordance with ASTM D1557-78, Method A.
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Portions of the bulk samples were subjected to remolded direct shear and
swell tests.
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The results of our laboratory tests are included in tabular form herewith.
The in-place density and moisture content results are included with the
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logs of the exploratory trenches in Appendix A.
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File No. D-3983-M02
November 30, 1987
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TABLE I
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Summary of Remolded Direct Shear Test Results*
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Angle of
Dry Moisture Unit Shear
Sample Density Content Cohesion Resistance
No. pcf % psf Degrees
Tl3-3 113.9 11.1 380 35
T26-4 103.2 15.5 100 16
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*Samples remolded to 90 percent of maximum dry density at optimum
moisture content.
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File No. D-3983-M02
November 30, 1987
Sample
No.
T13-3
T26-4
TABLE II
Summary of Laboratorv Compaction Test Results
ASTM D1557-78
Descriution
Dark blue, Clayey CRAVEL
Reddish-brown, Sandy CLAY
with trace cobbles
Maximum Dry
Density
pcf
126.3
114.8
Optimum
Moisture
% Drv Wt.
11.3
15.2
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File No. D-3983-M02
November 30, 1987
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TABLE III
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Summary of Laboratorv Expansion Index Test Results
I
Moisture Content
Before After
Test Test Dry
Sample Density Expansion
No. % % Dcf Index
Tl3-3 10.4 20.6 108.1 21
T26-4 12.3 33.6 101.3 152
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APPENDIX C
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SPECIFICATIONS FOR SITE GRADING
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1.0 GENERAL
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1.1 These specifications present general procedures and requirements
for grading and earthwork as shown on the approved grading plans
including preparation of areas to be filled, placement of fill,
installation of subdrains and excavations. The recommendations
contained in the geotechnical report are a part of the earthwork
and grading specifications and shall supersede the provisions
contained hereinafter in the case of conflict.
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1.2 Prior to the commencement of grading, a qualified geotechnical
consultant (soils engineer and engineering geologist, and their
representatives) shall be employed for the purpose of observing
earthwork procedures and testing the fills for substantial
conformance with the recommendations of the geotechnical report
and these specifications. It will be necessary that the
consultant provide adequate testing and observation so that he may
determine that, in his opinion, the work was accomplished in
general conformance with these specifications. It shall be the
responsibility of the contractor to assist the consultant and keep
him apprised of work schedules and changes so that he may schedule
his personnel accordingly.
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1.3 It shall be the sole responsibility of the contractor to provide
adequate equipment and methods to accomplish the work in
accordance with applicable grading codes or agency ordinances,
these specifications and the approved grading plans. If, in the
opinion of the consultant, unsatisfactory conditions, such as
questionable soil, poor moisture condition, inadequate compaction,
adverse weather, etc., are resulting in a quality of work less
than required in these specifications, the consultant will be
empowered to reject the work and recommend to the owner that
construction be stopped until the conditions are rectified.
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2.0 DEFINITIONS
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2.1 Owner shall mean the owner of the property or the person on whose
behalf the grading work is being performed and who has contracted
with the Contractor to have grading performed.
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2.2 Contractor shall mean the Contractor performing the site grading
work.
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2.3 Civil Engineer or Engineer of work shall mean the duly licensed
civil engineer who has been hired by the Owner to set basic
surveying data at the site to aid Contractor in conforming with
the grading and improvement plans.
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2.4 Soil Engineer shall mean a duly licensed Civil Engineer qualified
in soil engineering hired by the owner who is responsible for
having qualified representatives on-site to observe and test the
contractor's work for conformance with these Specifications.
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2.5 Engineering Geologist shall mean a duly licensed Engineering
Geologist hired by the Owner to provide geologic opinions and
recommendations during the site grading.
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3.0 MATERIALS
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3.1 Materials for compacted fill shall consist of any soil excavated
from the cut areas or imported to the site that, in the opinion of
the Soil Engineer, is suitable for use in construction of fills.
In general, fill materials can be classified as "soil" fills,
"soil-rock" fills or "rock fills.
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3.1.1.
"Soil" fills are defined as fills containing no rock
containing no rocks or hard lumps larger than 12 inches in
maximum dimension and containing at least 40 percent by
weight of material smaller than 3/4 inch in size.
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3.1.1.1
No rocks or hard lumps greater than 6 inches in
maximum dimension shall be placed in a zone
between finish grade surface and 3 feet below
finish grade.
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3.1.1.2
All rocks between 6 and 12 inches in maximum
dimension shall be placed at least 3 feet below
finish grade surface.
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3.1. 2
"Soil-rock" fills are defined as fills containing no
rocks or hard lumps larger than 4 feet in maximum
dimension and containing a sufficient matrix of "s01111
fill to allow for proper compaction of "soil" fill
around the rock fragments or hard lumps as specified
in Paragraph 6.2.
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3.1. 3
"Rock" fills are defined as fills containing no rocks
or hard lumps larger than 3 feet in maximum dimension
and containing little or no fines. Fines are defined
as material smaller tha~ 1 inch in maximum dimension.
The volume of fines shall be less than approximately
40 percent of the rock fill volume.
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3.2 Material of a perishable, spongy, or otherwise unsuitable nature as
determined by the Soil Engineer shall not be used in fills.
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3.3 "Soil" fill placed within at least the upper 3 feet of building pad
grade shall be select finish grade material that contains no rocks or
hard lumps greater than 6 inches in maximum dimension and that has an
Expansion Index of 50 or less when tested in accordance with UBC
Standard 29-2.
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3.4 The outer portion of fill slopes equal to at least the height of the
slope (measured horizontal to the slope face) or 10 feet, whichever
is less, should be composed of properly compacted "so1111 fill
materials approved by the Soil Engineer.
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3.5 Representative samples of soil materials to be used for fill shall be
tested in the laboratory by the Soil Engineer in order to determine
the maximum density, optimum moisture content, and, where
appropriate, shear strength and expansion characteristics of the
soil.
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3.6 During grading, soil types other than those analyzed in the Soil
Investigation may be encountered by the Contractor. The Soil
Engineer shall be consulted to determine the suitability of these
soils for use as fill and for use as finish grade soils conforming to
specifications in the Soil Investigation report.
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4.0 CLEARING AND PREPARING AREAS TO BE FILLED
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4.1 Areas to be excavated and filled shall be cleared and grubbed.
Clearing shall consist of complete removal above the ground surface
of all trees, stumps, brush, vegetation, man-made structures and all
similar debris. Grubbing' shall consist of removal of all stumps,
roots, buried logs and other unsuitable material and shall be per-
formed in all areas to be filled. All roots and other proj ections
over 1-1/2 inches in diameter shall be removed to a depth of 3 feet
below the natural surface of the ground and to a depth of 3 feet
below the sub grade of areas to be filled. Borrow areas shall be
grubbed to the extent necessary to provide materials free from
unsuitable matter.
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4.2 After clearing and grubbing of vegetable matter and obj ectionable
material, loose or porous soils shall be removed to the depth recom-
mended in the Soil Investigation. The depth of removal and
compaction shall be observed and approved by a representative of the
Soil Engineer. The exposed surface shall then be plowed or scarified
to a minimum depth of 6 inches and until the surface is free from
uneven features that would tend to prevent uniform compaction by the
equipment to be used.
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4.3 Where fills are constructed on hillsides or slopes, topsoil, slo-
pewash, colluvium or other loose or porous soils shall be removed and
the slope of the original ground on which the fill is to be placed
shall be stepped or "keyed" by the Contractor as indicated on Figure
C-l in these Specifications. The steps shall extend completely
through the soil mantle and into the underlying competent formational
material or, where competent formational soil is not present, into
compacted ground.
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4.4
After the foundation for the fill has
scarified, it shall be disced or bladed by
uniform, free from large clods, brought to
tent, then compacted as specified for fill.
been cleared, plowed or
the Contractor until it is
the proper moisture Con-
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5.0 COMPACTION EQUIPMENT
5.1
Compaction shall be accomplished by sheepsfoot
rollers, multiple-wheel pneumatic- tired rollers,
acceptable compaction equipment. Equipment shall
rollers, vibratory
or other types of
be of such a design
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that it will be capable of compacting the "soil" or "soil-rock" fill
to the specified density at the specified moisture content.
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5.2 Compaction of "rock" fills shall be performed in accordance with
Paragraph 6.3.
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6.0 PLACING, SPREADING AND COMPACTION OF FILL MATERIAL
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6.1 "Soil" fill, as defined in Paragraph 3 .1.1, shall be placed by the
Contractor in accordance with the following recommendations:
6 .1.1
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6 .1.2
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6.1. 3
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6 .1.4
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6 .1.5
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6 .1.6
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6.1. 7
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"Soil" fill shall be placed by the Contractor in layers
that, when compacted, shall not exceed 8 inches. Each
layer shall be spread evenly and shall be thoroughly mixed
during spreading to obtain uniformity of material in each
layer. The entire fill shall be constructed as a unit in
nearly level lifts. Rock materials greater than 12 inches
in maximum dimension shall be placed in accordance with
either Paragraph 6.2 or 6.3.
In general, the "soil" fill shall be
moisture content at or above the optimum
as determined by ASTM D1557-78.
compacted at a
moisture content
When the moisture content of "soil" fill is below that
specified by the Soil Engineer, water shall be added by the
Contractor until the moisture content is in the range spe-
cified.
When the moisture content of the "soil" fill is above the
range specified by the Soil Engineer or too wet to achieve
proper compaction, the "soil" fill shall be aerated by the
Contractor by blading/mixing, or other satisfactory methods
until the moisture content is within the range specified.
After each layer has been placed, mixed, and spread evenly,
it shall be thoroughly compacted by the Contractor to a
relative compaction that is not less than 90 percent.
Relative compaction is defined as the ratio (expressed in
percent) of the in-place dry density of the compacted fill
to the maximum laboratory dry density as determined in
accordance with ASTM D1557 -78. Compaction shall be
continuous over the entire area, and compaction equipment
shall make sufficient passes so that the desired density
has been achieved throughout the entire fill.
Potentially "medium" to "higblT expansive soil (soils having
an Expansion Index of greater than 50) may be used in fills
below a depth of 3 feet below finish grade and shall be
compacted at a moisture content of 2 to 4 percent greater
than the optimum moisture content for the material.
Properly compacted "soil" fill shall extend to the design
surface of fill slopes. The surface of fill slopes shall
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6.1.8
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be back-rolled with a heavy-duty loaded sheepsfoot or
vibratory roller at maximum 4-foot fill height intervals
and upon completion they shall be track-walked with a dozer
so that a dozer track covers all slope surfaces at least
twice.
As an alternative to track-walking, upon completion, the
slopes may be overbuilt by at least 5 feet and then trimmed
back to the design grade.
6.2 "Soil-rock" fill, as defined in Paragraph 3.1.2, shall be placed by
the Contractor in accordance with the following recommendations:
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6.2.1
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6.2.2
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6.2.3
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Rocks larger than 12 inches but less than 4 feet in maximum
dimension may be incorporated into the compacted "soilll
fill, but shall be limited to the. area measured 5 feet
minimum horizontally from the slope face and 2 feet below
finish grade or 3 feet below the deepest utility, whichever
is deeper.
Rocks or rock fragments up to 4 feet in maximum dimension
must be individually placed.
For individual
provided between
equipment.
placement, sufficient space
rocks to allow for passage of
shall be
compaction
6.3 "Rock" fills shall be placed by the Contractor in accordance with the
following recommendations:
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6.3.1
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6.3.2
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The base of the "rock" fill shall be placed on a sloping
surface (minimum slope of 2 percent, maximum slope of 5
percent). The surface shall slope toward suitable drainage
outlet facilities. The "rock" fills shall be drained
during construction so that a hydrostatic pressure buildup
does not develop. The drains shall be permanently
connected to controlled drainage facilities to control
postconstruction infiltration of water.
"Rock" fills shall be placed in lifts not exceeding 3 feet.
Placement shall be by rock trucks traversing previously
placed lifts and dumping at the edge of the currently
placed lift. Spreading of the "rock" fill shall be by
dozer to facilitate "seating" of the rock. The "rockl1 fill
shall be watered heavily. during placement. Watering shall
consist of water trucks traversing in front of the current
rock lift face and spraying water continuously during rock
placement. Compaction equipment such as a 20-ton steel
vibratory roller or other compaction equipment providing
suitable energy to achieve the required compaction or
deflection as recommended in Paragraph 6.3.3 shall be
utilized. The number of passes to be made will be
determined as described in Paragraph 6.3.3.
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6.3.3
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6.3.4
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6.3.5
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6.3.6
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6.3.7
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Plate bearing tests, in accordance with ASTM Dl196-64, may
be performed in both the compacted "soil" fill and in the
"rock" fill to aid in determining the number of passes of
the compaction equipment to be performed. If performed, a
minimum of three plate bearing tests shall be performed in
the properly compacted "soil" fill (minimum relative
compaction of 90 percent). Plate bearing tests shall then
be performed on areas of "rock" fill having two passes,
four passes and six passes of the compaction equipment I
respectively. The nwnber of passes required for the IIrockll
fill shall be determined by comparing the results of the
plate bearing tests for the "soil" fill and the "rock" fill
and by evaluating the deflection variation with number of
passes. The required number of passes of the compaction
equipment will be performed as necessary until the plate
bearing deflections are equal to or less than required.
A representative of the Soil Engineer shall be present
during rock fill operations to verify that the minimum
number of "passes II have been obtained, that water is being
properly applied and that specified procedures are being
followed. At least two plate bearing tests shall be
performed per day in the "rock" fill. The actual number of
plate bearing tests will be determined by the Soil Engineer
during grading with at least one test being performed for
each approximately 5,000 cubic yards of "rock" fill placed.
Test pits shall be excavated by the Contractor so that the
Soil Engineer can state that, in his opinion, sufficient
water is present and that voids between large rocks are
properly filled with smaller rock material. In-place
density testing will not be required in the "rock" fills.
To reduce the potential for "piping" of fines into the
"rock" fill from overlying Ilsoil" fill material, a 2-foot
layer of graded filter material shall be placed above and
below the "rock" fill. The gradation of the graded filter
material will be determined at the time the "rock" fill is
being excavated. Materials typical of the "rock" fill
should be submitted to the Soil Engineer in a timely manner
to design the graded filter.
All "rock" fill placement shall be continuously observed
during placement by representatives of the Soil Engineer.
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7.0 OBSERVATION AND TESTING
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7.1 The Soil Engineer shall be the Owners representative to observe and
make tests during fill foundation preparation and filling and
compaction operations. In general, no more than 2 feet of II soil" or
"soil-rock" fill in vertical elevation shall be placed without at
least one field density test being made within that interval. In
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addition, a m~n~mum of one field density test shall be made for every
2,000 cubic yards of "soill1 or "soil-rock" fill placed and compacted.
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7.2 The Soil Engineer shall make random field density tests of the
compacted "soilll or "soil-rock" fill to provide a basis for
expressing an op~n~on as to whether the fill material is compacted as
specified. The basis for his opinion that the fill material has been
compacted to at least the minimum relative compaction specified shall
be that no tests in compacted or recompacted fill areas indicate a
relative compaction of less than that specified. Density tests shall
be made in the compacted materials below any disturbed surface. When
these tests indicate that the density of any layer of fill or portion
thereof is below that specified, the particular layer or areas
represented by the test shall be reworked until the specified density
has been achieved.
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7.3 The Soil Engineer shall verify that the m~n~mum number of "passes"
have been obtained per the criteria discussed in Section 6.3.3. The
Soil Engineer shall make random observation pits and may make plate
bearing tests of the placed "rock" fills. The observation pits will
be excavated to provide a basis for expressing an opinion as to
whether the "rock" fill is properly seated and sufficient moisture
has been applied to the material. If performed, plate bearing tests
will also be performed randomly on the surface of the previously
placed lift. Plate bearing tests will be performed to provide a
basis for expressing an opinion as to whether the "rock" fill is
adequately seated. The maximum deflection in the "rock" fill
determined in Section 6.3.3 shall be less than the maximum deflection
of the properly compacted "soil" fill. When any of the above
criteria indicate that a layer of "rock" fill or any portions thereof
is below that specified, the particular layer or area represented by
the criteria shall be reworked until the "rock" fill has been
adequately seated and sufficient moisture applied.
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7.4 A settlement monitoring program designed by the Soil Engineer may be
conducted in areas of "rock" fill placement. The specific design of
the monitoring program shall be as recommended in the Conclusions and
Recommendations section of the project soils report or in the final
report of grading.
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7.5 The Soil Engineer shall observe the placement of subdrains so that he
can state his opinion that the subdrains have been placed and
constructed in substantial accordance with project specifications.
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7.6 Testing shall conform to the following Standards as appropriate:
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7.6.1 "Soil" and "Soil-Rock" Fills:
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*Field Density Test, ASTM D1556-B2, "Density of Soil In-Place By
the Sand-Cone Method.
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*Field Density Test, Nuclear Method, ASTM D2922-Bl, "Density of
Soil and Soil-Aggregate In-Place by Nuclear Methods (Shallow
Depth) . "
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*Laboratory Compaction Test, ASTM 01557 - 78, "Moisture-Density
Relations of Soils and Soil-Aggregate Mixtures Using 10-Pound
Hammer and l8-Inch Drop."
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*Expansion Index Test, Uniform Building Code Standard 29-2
IIExpansion Index Test."
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7.6.2 "Rock" Fills:
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*Field Plate Bearing Test, ASTM 01196-64 (Reapproved 1977)
"Standard Method for Nonrepresentative Static Plate Load
Tests of Soils and Flexible Pavement Components, For Use in
Evaluation and Design of Airport and Highway Pavements."
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8.0 PROTECTION OF WORK
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8.1 During construction, the Contractor shall properly grade all
excavated surfaces to provide positive drainage and prevent ponding
of water. He shall control surface water to avoid damage to
adjoining properties or to finished work on the site. The Contractor
shall take remedial measures to prevent erosion of freshly graded
areas and until such time as permanent drainage and erosion control
features have been installed. Areas subjected to erosion or
sedimentation shall be properly prepared in accordance with the
Specifications prior to placing additional fill or structures.
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8.2 After completion of grading and when the Soil Engineer has finished
his observation of the work, no further excavation or filling shall
be done except under the observation of the Soil Engineer.
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9.0 CERTIFICATIONS AND FINAL REPORTS
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9.1 Upon completion of the work, Contractor is to furnish owner a
certification by the Civil Engineer stating that the lots are graded
to within 0.1+ foot vertically of elevations shown on the grading
plan and that all tops and toes of slopes are wi thin 0.5 foot
horizontally of the positions shown on the grading plans. After
installation of the subdrain, the project civil engineer should
survey its location and prepare "as-builtll plans of the subdrain
location. The project civil engineer should verify the proper outlet
for the sub drains and the contractor should ensure that the drain
system is free of obstructions.
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9.2 Owner is also to furnish a final as-graded soils and geologic report
satisfactory to the appropriate governing or accepting agencies and
signed by a duly licensed Civil Engineer qualified in soil
engineering and by a Certified Engineering Geologist, indicating that
the work was done in substantial conformance with the Specifications
or approved changes to the Specifications as authorized under
Paragraph 1.4 of these Specifications.
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10.0 STREETS, STORM DRAINS, SEWERS AND LOTS IN ROCK AREAS
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10.1 Considerations should be given to undercutting all streets in rock
areas 10 feet and the storm drains, sewerlines and sewer laterals
installed. The spoil from the sewer trench is to be left in the
street and the sewer trench is to be backfilled with material as
described in Paragraph 3.1.1 of these Specifications and to City of
Encinitas requirements.
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10.2 The lots in the rock areas shall be undercut 2 feet and material as
described in Paragraph 3.1.1 is to be placed on the lots. When the
lots are fine-graded, the spoil from the lots is to be placed in the
street and the streets brought up to within 1.5 feet of top of curb
with material described in Paragraph 3.1.1 of these Specifications.
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10.3 Storm drains in rock areas are to be backfilled with material as
described in Paragraph 3.1.1 of these Specifications and to City of
Encinitas requirements. All spoil from the storm drain trenches is
to be hauled and placed in the fill area at Contractor's expense as
specified in Paragraph 6.0 of these Specifications.
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File No. D-3983-M02
I November 30, 1987
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STRIP AS SPECIFIED
ORIGINAL GROUND
" N
"" 1M SLOPE RATIO' ~
""
~"~"'" "-
----..:.. . "~ PROPERLY COMPACTED
SLOPE TO BE SUCH TH~T i~.. .:. . " FILL SOIL
SLOUGHING OR SLIDING L-_~,..:.7.. ........
DOES NOT OCCUR ~'~ ' ........
L_~~ "
~\. .~. "
REMOVE ALL L '~7. " L
UNSUITABLE MATERIAL I I' ~~.
, VAi1IES ,L- . . ]
I SE~BN"OTE I S::'
li0TES
NO SCAL E
The minimum width "B" of key shall be 2 feet wider
than the compaction equipment, and not less than 10
feet.
The outside edge of bottom key shall be below top-
sailor loose surface material.
Keys are required where the natural slopes are
steeper than 6 horizontal to 1 vertical, or where
specified by Soil Engineer.
TYPICAL BENCHING DETAIL
LONE JACK ROAD PROPERTY
ENCINITAS, CALIFORNIA
I Figure C-1
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"'0' () <J '0'00 '()"'/";"o"O",,'O,O':
cQ .0", 0,' '00 'i) 00 " V 'h', 0.. '
. 0 ' '0 0, c> w, '
'0'" ' 0' () , 00",',.:.. 1//~'0-'-...~
. OD " "0-
o '(J 0 00' " , , 0
'W (J, ' ; ','000 0 "
, 0 '0' (J, ' ' ,
(] 0 0..", 0' 0 ' ',0:
'0" 0 ' (J, ' '~ ,00,'
",Va ,0',' ·
~ ," 0, (l 0: <:7, '0.
o . 0 ' 0' .---' , (J, 0 '
<<: D' . C7 I' " ' , " oD
" '<> ,Q ,/ , 0
\ I ' '
,0 ' '0 ' / 00'0'
l' 0" o' .......~. ~.' . .
///A-';;::V I
21 I
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File No. D-3983-MD2
November'3D, 1987
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-r-
_ 6"
o-i:i-.\'\<( t
".....
BEDROCK
( FORMATIONAL SOIL)
'"
,
NOTE'
4'
r APPROVEO FILTER FA8RIC
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OPEN -GRADEO I" MAX, AGGREGATE
2'
6" PERFORATED A8S PIPE,
I" TO 2" CLEAR FROM BOTTOM
OF TR ENCH ,
USE SDR 35 FOR UPTO 30' FILL COVER
, USE SDR 21 FOR UP TO 100' FILL COVEF
IF CLAS~ 2 PERMEABLE MATERIAL ( PER SEC, 6B-1.025
CALTRANS STANDARD SPECIFICATIONS) IS USED THE
FILTER FABRIC MAY 8E DELETED
Figure C-2
NO SCALE
RECOMMENDED CANYON SUBDRAIN DETAIL
LONE JACK ROAD PROPERTY
ENCINITAS, CALIFORNIA
NoText