404, Construct a tennis court, Studies & Reportsr
GEOTECHNICAL
�A��®ENGINEERING
„_,..,..... CONSULTANTS. INC.
2483 E. ORANGETHORPE AVE. / FULLERTON, CA 92631-5304 / (714) 773-1232 Toll Free: (800) 422-4117
GEOTECHNICAL REVIEW OF GRADING PLANS, #2 MORGAN LANE,
ROLLING HILLS, COUNTY OF LOS ANGELES, CALIFORNIA
LEGAL DESCRIPTION: LOT 8, MORGAN LANE
JOB NO. 5676-pl-A7
June 2, 1987
PREPARED FOR:
Mr. Mike Gray
4125 Miraleste Drive
Rancho Palos Verdes, Ca 90274
Job No. 5676-P1-A7
June 3, 1987
Mr. Mike Gray
4125 Miraleste Drive
Rancho Palos'Verdes, Ca. 90274
Subject: Geotechnical Review of Grading Plans #2 Morgan Lane, Rolling
Hills, County of Los Angeles, California
Legal Description: Lot 8, Tract 33871.
References:
1. AAKO Geotechnical Engineering Consultants, Inc., 1 April
1985, "Grading Compaction Report for the Backfill of the
Storm Drain Trench, Water Line and Utility Trench, Morgan
Lane, Tract 33871, Rolling Hills Estates, California," Job
#4499-C1-85.
2. AAKO Geotechnical Engineering Consultants Inc., 21 November
1984, "Geotechnical Report of Rough Grading Observation for
Morgan Lane, Lots 1-8, Tract 33871, Rolling Hills Estates,
Los Angeles County California, "Job #4499-C2-85.
3. AAKO Geotechnical Engineering Consultants, Inc., 24 October
86, "Addendum Geotechnical Engineering Report of Rough
Grading Evaluation for Development of Morgan Lane, Tract
33871, Rolling Hills Estates, Los Angeles County,
California," Job No. 4499-C1B-A6.
4. County of Los Angeles, "Soils Engineering Section Report
Review Sheet", several dates.
5. Eastman, Ray, Engineering Geologist, 9 September 1986,
"Geologic Inspections, Canyon Cleanout for Compacted Fill
and Separate Subdrain Installation, Lot 8, Morgan Lane,
Rolling Hills, California", Project No: 383.
6. Lockwood -Singh and Associates, 1 June 1978, "Report of
Geotechnical Investigation, Tentative Tract No. 33871,
Located East of Morgan Lane, Rolling Hills, in the County of
Los Angeles California," Project Number 86-122.
7. Norcal Engineering, 8 September 1986, "Inspection of Grading
Operations - Portion of Lot 8, Tract 33871, Located East of
Morgan Lane, Rolling Hills, in the County of Los Angeles,
Calfifornia," Project Number 86-122.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676-p1-A7 June 3, 1987 -2-
8. Sayre -Smith & Nesbit, Inc, undated, "Site Plan," Job No.
8714.
9. South Bay Engineering, 10 August 1981 "Grading Plan for
Tract 33871", Job No. G-0418-5.
10. U.S.G.S., 1964, "Topographic Qudrangle Map -Torrance Sheet,"
7.5 Minute Series, photorevised 1981 at 2000 scale.
Dear Mr. Gray:
In accordance with your request and authorization, a geotechnical
engineering review of the Reference #3 plans has been performed. This
letter presents the findings of the review, plus conclusions, and
recommendations pertaining to the geotechnical engineering aspects of
the project.
This review is based on .the Reference #6 report, and on
inspections made for the grading of Morgan Lane (References #1, #2 and
#3). The subsurface and foundation conditions are discussed and
preliminary recommendations for the soils engineering aspects of the
project are presented.
If you have any questions concerning our findings, please call at
your convenience.
Respectfully submitted,
AAKO GEOTECHNICAL ENGINEERING CONSULTANTS, INC.
=Z -tee/ ��n
t•REbtkit: CURI 1S, C.t.ti. 1044
Engineering Geologist
FC/JRG/rlh
FREDERICK CURTIS
NO. 1044
CERTIFIED
ENGINEE.ING
• GEOLOGIST
EXP.
FESSIONry
��NR G'F�Ft
m
No. 24711
Exp. 12.31.89
CIV1���
FOFCA1.\O
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676-P1-A7 June 3, 1987 -3-
SCOPE
The findings, conclusions, and recommendations reflect our best
estimate of 'soil conditions based on the data obtained from a limited
subsurface exploration performed during the previous field
investigations and inspections performed at the site. The conclusions
and recommendations are based on generally accepted engineering
principles and practices. No further warranties are implied nor made.
Due to the possible variability of soils and subsurface
conditions within the site, conditions may be encountered during
grading and development that may differ from those presented herein.
Should any variations or unusual conditions become apparent during
grading and development, this office shall be contacted to evaluate
these conditions prior to continuation of work and to make any
necessary revisions to the recommendations.
This office shall be notified if changes of ownership occur or if
final plans for the site development indicate structure areas, type of
structures, or structural loading conditions differing from those
presented in this report.
If the site is not developed or grading does not begin within 24
months following the date of this report, further investigation may be
required to ensure that the surface or subsurface conditions have not
changed.
Any charges for necessary review or updates will be at the
prevailing rate at the time the review work is performed.
PROPOSED DEVELOPMENT
A one and two story dwelling is planned for the subject site.
The structure is proposed to be supported on continuous and spread
footings. Loads on the footings are unknown at this time but are not
anticipated to exceed 2000 plf for continuous footings and 50 kips for
column loads. Anticipated grading will include cuts and fills of up
to 12 feet.
SITE CONDITIONS
The subject site is roughly triangular, with an area of
approximately 2.2 acres.
The property is situated on a gentle southwest facing natural
slope with slopes ranging from 5:1 to 10:1 (horizontal to vertical).
The property is covered with seasonal weeds and grasses.
Natural drainage is by sheet flow into a natural swale draining
southwesterly through the center of the property.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676-P1-A7 June 3, 1987 -4-
The western mid section of the site in the natural swale area
contains fill placed under the observation of others. The fill has
subsequently .been observed by the undersigned and appears adequately
compacted. See the plot plan and the Reference #3, 5, and 7 reports for
approximate limits of fill and description of fill placement.
Adjoining the property are the following:
N'ly--Vacant Property E'ly--Morgan Lane
S'ly--Morgan Lane W'ly--Residences
EARTH MATERIALS
Earth materials on the site include fill, slopewash and bedrock.
Earth materials are briefly described.
Fill (Symbols-af and afe)
Fill comprise of clayey silt derived from the natural slopewash (i.e.,
topsoil) at the site with varying amount of siltstone and sandstone
bedrock fragments. The limits of loose fill (af) less than 1' in
thickness, and engineered fill (afe) are shown in the attached Site
Plan/Geologist Map.
Slopewash (Symbol-Qsw)
Slopewash is composed of clayey silt with moderate to abundant amounts
of siliceous siltstone, poorly consolidated, porous, and prone to
downslope creep.
Bedrock (Symbol-Tma)
Bedrock belonging to the Miocene age Alamira member of the Monterey
formation is moderately hard to hard and comprises interbedded
siltstone and sandstone. Bedding planes of within the bedrock
generally closely parallel the existing topography.
No groundwater was encountered. However, very moist to wet
bedrock was encountered in the canyon cleanout for the Morgan Lane
road fill near the southerly margin of the site, per Reference #2
Expansion Characteristics
Results of previous laboratory expansion tests indicate the
typical on -site slopewash and fill soils as being moderately to highly
expansive with expansion index values ranging from 61 to 113. Visual
examination and classification indicate the bedrock to be moderately
to highly expensive.
AAKO�NE`"N"AL
ONS<J ERING
LTANTS. INC
Job No. 5676-P1-A7 June 3, 1987 -5-
SEISMICITY
The subject property is situated in earthquake prone Southern
California. 'Proximally, as well as regionally, there is evidence of
geologically youthful fault movement. Moreover, earthquakes
associated with historic events have been qualified by nonlinear
measure (intensity) and quantified by linear measure
(seismograph/magnitude).
No active faults (i.e., having ruptured the surface within the
last 11,000 years) known to be present within or in the near vicinity
of the property. Accordingly, the site is not within an Alquist-
Priolo Special Studies Zone and, therefore, does not require a
comprehensive subsurface exploratory fault investigation.
Significant faults, historic earthquake epicenters and their
location relative to the site are delineated on Drawing S-1 fault
location map in Appendix F. Of the regional faults shown, those
considered to be causative faults (i.e., active faults having the
potential for a Richter magnitude 5.0 or greater earthquake that could
affect the site) are listed on Table S-1 in Appendix F.
Numerous lesser faults have been mapped in the nearby foothill
and mountainous terrain of the Palos Verdes Hills and San Monica
Mountains. Public and private investigators have obtained limited,
but not necessarily conclusive, evidence of Quaternary displacement
for some.
Based on the presented data on Table S-1, the design earthquake
for the site is a 6.8 Richter magnitude event along the Newport -
Inglewood fault which underlies the northeasterly portion of the site.
The following seismic parameters can be assumed at the site:
Peak Bedrock Acceleration
Repeatable Ground Acceleration
Peak Event Period of Bedrock Acceleration
Estimated Duration of Strong Ground Shaking
CONCLUSIONS AND RECOMMENDATIONS
0.32g
0.21g
.35 sec
15-24 sec
In the opinion of the undersigned, the subject property is
suitable for the proposed residential development from a soils
engineering and engineering geologic standpoint, provided the
recommendations contained hereinafter are incorporated in the project
designs and specifications. Earth materials on the site will be
adequate for the support of proposed structures and compacted fills.
The proposed structures, grading, and other site improvements will not
cause adverse safety hazards or instability to adjacent properties or
structures. Conversely, the adjacent properties or their structures
will not cause adverse safety hazards or instability to the proposed
AAKOGEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676+ 1-A7 June 3, 1987 -6-
development. The site is stable and there is no risk of land failure
resulting from the planned development.
o There are no known active or potentially active faults that
transect the subject property or proximity.
o Existing loose fill, slopewash deposits, and near surface
weathered bedrock deposits are deemed unsuitable for the
support of compacted fill and structures. Moreover, these
materials extend 5' to 7' or more below existing site grade.
o Competent bedrock and engineered fill are deemed suitable
for the support of structures and fill.
o Data obtained from grading inspections site reconnaissance
suggest that the bedrock underlying the site will be stable
for support of the planned dwelling and appurtanances.
o Surficial instability is limited to minor erosion features
and creep of the outer surface of the weathered bedrock and
soil mantle on the natural slope.
o Excavation and trenching in bedrock should be readily
accomplished with slight to moderate difficulty using
conventional earthmoving equipment.
o Anticipated subgrade earth materials are classified
moderately to highly expansive.
o All natural materials are suitable for use in fills when
compacted in accordance with the recommendations contained
herein.
o Geologic conditions at the site are consistent with those
described in Reference 3.
o A subdrain must be constructed above the existing canyon
fill to intercept potential subsurface water seepage.
o Being located in Southern California, the site is subject to
strong ground shaking by nearby or distant earthquakes.
However, the performance of wood -frame structures built in
compliance with current building codes and founded in firm
ground, such as occurs within the underlying bedrock, has
generally proven to be satisfactory under conditions of
earthquake -induced strong ground shaking.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 56764:1-A7 June 3, 1987 -7-
Seismic Design Criteria
A repeatable ground acceleration of 0.21g may be expected to
affect the 'subject site within the economic lifetime of the planned
dwelling. If this value is used for structural design of the dwelling,
a design earthquake can be expected to cause very little or no damage to
the structure. However, to design a building for this acceleration
would impact considerable, and possibly unnecessary, expense to the
design. Based on empirical data, if one or two story wood frame
structures are designed for potential acceleration of 50% to 60% of the
repeatable ground acceleration, minor to moderate damage will be
sustained by the structure. However, in total structural failure or
collapse would be likely. It is the responsibility of the structural
engineer to evaluate the allowable degree of structural damage from a
design earthquake, and design the dwelling accordingly.
Rough Grading Recommendations
All existing vegetation and debris shall be removed from areas to
receive compacted fill. Man-made obstructions shall be overexcavated
and exported from the site. Trees and their root systems shall be
overexcavated down to competent soils, ensuring that at least 95% of
the roots are removed.
In areas to receive fill, all existing loose fill, slopewash, and
unsuitable weathered bedrock should be overexcavated down to competent
bedrock, which may require overexcavation to depths of 5' to 7' or
more below existing site grade.
In fill areas where the natural slope exceeds 5:1 (horizontal to
vertical), fill shall be properly keyed and benched into competent
bedrock. Keys and benches shall be sloped back into the hillside at a
minimum 2% gradient. Minimum fill key width shall be 15'.
The cut portion of shall building pads shall be overexcavated a
minimum depth of 3' below finish grade. This blanket fill will; 1)
support structures and minimize the potential for excessive
differential settlements due to differing compressibility of the fill
and bedrock, and; 2) minimize the potential for infiltration of
surface water into the bedrock.
The project Engineering Geologist shall inspect all
overexcavation areas prior to placement of fill.
All overexcavation bottoms and areas to receive fill shall be
scarified a minimum of six(6) inches, watered or aerated as necessary
to obtain near optimum moisture content, mixed to a uniform
consistency, and compacted to a minimum of 90% of the laboratory
maximum density.
AAKO
GEOTECHNICAL
NEERING
'ONSULTANTS.INC.
Job No. 5676-P.1-A7 June
1987 -8-
A shrinkage factor of 16 to 17 percent for soil and slopewash and
1 to 2 percent for bedrock may be assumed in estimating earthwork
quantities. Minimal subsidence of the bedrock due to grading is
anticipated:
All fill soil, whether natural or import, shall be approved by
the soils engineer or his representative prior to placement as
compacted fill. All fill soil shall be free from vegetation, organic
material, and debris. Approved fill soil shall be placed in
horizontal lifts not exceeding 6 inches in thickness, and watered or
aerated and mixed as necessary to obtain a uniform near -optimum
mixture content.
Following placement, each lift shall be completely and uniformly
compacted to not less than 90% of the laboratory maximum density as
determined be ASTM test method D-1557-78. The soil►engineer or his
representative shall observe the placement of fill and shall take
sufficient tests to verify the moisture content, and uniformity and
degree of compaction obtained. In -place soil density should be
determined by the sand -cone method, in accordance with ASTM test
method D-1556-64 (74), or equivalent test method acceptable to the
local building authority.
Finish fill and cut slopes shall not be inclined steeper than 2:1
(horizontal to vertical). Fill slope surfaces shall be compacted to
90% of the laboratory maximum density by either overfilling and
cutting back to expose a compacted core or by approved mechanical
methods.
If southerly or westerly facing cut slopes are planned, they may
expose unsupported bedding planes (i.e., daylighted bedding). Any
such slopes must be inspected during grading to provide timely
recommendations for safe construction.
Foundation Recommendations
A foundation system consisting of continuous and spread footings
is recommended for the support of the proposed dwelling structure.
Footings shall be founded into competent bedrock or properly compacted
fill.
Footings in bedrock shall extend a minimum depth of 18 or 24
inches (for 1 or. 2 story structure respectively) into competent
bedrock as determined by Engineering Geologist. Notwithstanding,
embedment of all footings on or near existing or proposed slopes
should be determined by a minimum 5' horizontal edge distance measured
from the bottom ouside edge of the footing to the slope face or the
soil/bedrock interface. Continuous footings shall be a minimum of 15"
wide and shall be reinforced with a least two (2) #4 reinforcing bars
at the top and two (2) #4 reinforcing bars at the bottom of the
footings.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676-.1-A7 Juhe 3, 1987 -9-
A safe allowable soil bearing value of 2,000 p.s.f. is
recommended for the design of the continuous and spread footings at a
typical 18" depth into the bedrock and a typical 15" footing width.
This value may be increased by 15% for each additional foot of depth
and/or width, to a maximum of 3,500 p.s.f.. A 1/3 increase in the
above bearing value may be used when considering short term loading
from wind or seismic sources. Using this bearing value, settlement of
the proposed structure is not anticipated to exceed a maximum of 1/2"
or a differential settlement of 1/4" between foundation elements.
Footings in properly compacted fill comprised of onsite slope
wash and bedrock earth maerials, shall be founded a minimum depth of
24" below lowest adjacent finished grade. Continuous footings shall
be a minimum width of 15" and be reinforced with at least two (2) #4
reinforcing bar at the top and two (2) #4 reinforcing bars at the
bottom of the footings.
A safe allowable bearing value of 1,800 p.s.f. is recommended for
the design of the continuous and spread footings at a typical 18"
depth into fill soils, and a typical 15" footing width. This value
may be increased 10% for each additional foot of depth and/or width,
to a maximum of 3,500 p.s.f. A 1/3 increase in the above bearing
value may be used when considering short term loading from wind or
seismic sources. Using this bearing value, settlement of the proposed
structure is not anticipated to exceed a maximum of 1/2" or a
differential settlement of 1/4" between foundations elements.
The proposed dwelling should be designed in accordance with
applicable earthquake standards contained in Chapter 23 of the Uniform
Building Code.
Retaining Wall Recommendations
Retaining walls supporting compacted fill shall be designed to
support the following active lateral soil pressures:
o Equivalent Fluid Pressure: 40 p.c.f. - Level Backfill
45 p.c.f. - 3:1 Sloping Backfill
55 p.c.f. - 2:1 Sloping Backfill
Other surcharge loads acting on the backfill shall also be
considered in the design. The footings shall be found to the same
depths as for standard foundations and may be designed for the same
allowable bearing value.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676- 1-A7 June 3, 1987 -10-
Due to the shallow angle of bedding planes encountered in the
exploratory test pits, additional surcharge due to geologic planes of
weakness need not be considered in the design of retaining walls.
This conclusion shall be confirmed by geologic mapping by the
Engineering Geologist during site grading. Additional retaining wall
design parameters. will be provided in the final rough grading
observation report.
For lateral restraint the following soil design parameters may be
used when all foundation recommendations are followed:
o Passive Lateral Pressure:
Bedrock: 350 p.c.f. equivalent fluid pressure
Fill: 250 p.c.f. equivalent fluid pressure
o Coefficient of Friction: 0.35
An adequate subdrain system shall be constructed behind and at
the base of all retaining walls to allow adequate drainage and to
prevent buildup of excessive hydrostatic pressures.
Backfill directly behind retaining walls may consist of self
compacting 3/8" maximum diameter pea -gravel or clean sand water jetted
into place to obtain proper compaction. If other types of soil are
used for backfill, mechanical compacting methods will be necessary to
obtain a relative compaction of at least 90% of maximum density.
Backfill directly behind retaining walls shall not be compacted by
wheel, track or other rolling unless the wall is designed for the
surcharge loading from the compaction equipment.
If gravel, clean sand, or other imported granular backfill is
used behind the retaining wall, the upper 18 inches of backfill shall
consist of typical on -site soils to prevent the influx of surface
runoff into the granular backfill and into the subdrain system.
Retaining Wall Construction Cut Recommendations
Construction cuts for retaining walls will be a maximum of 20
feet in height. The following are our recommendations to ensure
construction safety and stability of the unsupported, temporary
construction cuts:
1. Temporary construction cuts in fill made during the dry
seasons (when precipitation is not anticipated) should be
inclined at 3/4:1 (horizontal to vertical). If unseasonal
rainfall is encountered, the protection methods in
recommendation #2 (below) should be followed.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676e 1-A7 June 3, 1987 -11-
2. Temporary construction cuts in fill made during the wet
seasons (when precipitation is anticipated) should be
inclined at 1/2:1 (horizontal to vertical). In addition,
during rains, and overnight, the open cut shall be
adequately protected from precipitation and/or erosion, by
plastic sheeting and adequate temporary drainage to carry
runoff away from the cut slopes.
3 Temporary cuts in bedrock may require flatter back cuts.
Recommendation for bedrock back cuts will be provided by the
Engineering Geologist during site grading.
4. Where more restrictive, the safety requirements of OSHA
regulations shall be followed.
5. Workers should not be allowed to stand or walk behind
retaining walls (i.e, between the retaining wall and the
back cut area) at any time during construction due to the
possibility of injury by falling rock fragments or back cut
failures.
Floor Slab Recommendations
Concrete floor slabs shall be constructed for high
expansive soil conditions in accordance with the following section:
o 5 inches of concrete reinforced with #4 reinforcing bars at
18 inches on -center, in each direction, at the vertical
center of the slab, and structrually tied to the footings
with #4 reinforcing bar at 18 inches o.c.
o 6 inches of sand or approved granular soil over natural
subgrade.
In living areas or where moisture sensitive floor coverings are
anticipated over the slab, a 6 mil plastic moisture barrier should be
placed beneath the concrete slabs. The plastic moisture barrier shall
be overlain with a minimum of 2 inches of sand to aid in concrete
curing and to minimize the potential for punctures during
construction.
The slab subgrade shall be presaturated to a least 125% of
optimum moisture content to a depth of 24 inches prior to pouring
concrete.
As an alternate to the above, a post tensioned slab is highly
recommended. The post tensioned slab must be designed by a qualified
engineer.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 56761,1-A7 June 3, 1987 -12-
Finish Grading Recommendations
To provide positive site drainage, finish lot grading should
include a minimum positive gradient of 3% away from structures for a
minimum distance of six (6) feet, and a minimum gradient of 2% to the
street or other approved drainage course. Where drainage is over
paved surfaces or V-drains, only a 1% drainage gradient is necessary.
All roof or canopy runoff and pad drainage shall be conducted to
the street or off the site in an approved non -erosive manner.
Drainage off the property shall be accomplished in an approved manner
to prevent erosion or instability.
Water from off -site sources should not be allowed to discharge
onto the subject property.
The watering of slopes on the site should be limited to the
minimum amount required for plant growth.
Trench Backfill Recommendations
Utility trench excavations in slope areas or within the zone of
influence of structures should be properly backfilled in accordance
with the following recommendations: •
Pipes shall be bedded and backfilled with self compacting
backfill, or approved granular soil, to a depth of at least 1 foot
over the pipe. This backfill shall be uniformly compacted, by
mechanical means, to a firm and unyielding condition. Water jetting
of the granular soils is not recommended due to the impermeable nature
of the on -site soils.
The remainder of the backfill may be fine grained non -granular
soils, which shall be placed in lifts not exceeding 12 inches in
thickness, watered or aerated to near optimum moisture content, and
mechanically compacted to a minimum of 90% of the laboratory maximum
density.
Where utility trenches are within 5 feet of a top of slope or on a
slope, the trench shall be bedded with clean sand or approved granular
soil to a depth of 1 foot over the pipe. The remainder of the backfill
shall consist of typical on -site suricial soil and shall be mechanically
compacted as noted above, not water jetted, to achieve compaction.
These trenches should have a minimum of 2' of soil backfill over the
sand to minimize the potential for washout.
AAKO
GEOTECHNICAL
CCONSULTANTS, INC
Job No. 5676i)1-A7 June
1987 -13-
Inspection
Subsequent to formulation of final development plans and
specifications, but prior to construction, grading and foundtion plans
should be reviewed by the project Soils Engineer and Engineering
Geologist to verify compatibility with site geotechnical conditions,
and conformance with recommendations contained herein.
All rough grading of the property must be performed under the
observation and testing of the Geotechnical Consultant. Rough grading
pertains to, but is not limited to, overexcavation cuts, fill
placement, and temporary and permanent cut slopes.
The project Soils Engineer and/or Engineering Geologist should
inspect all foundation excavations. Inspections should be made prior
to installation of concrete forms and reinforcing steel, to verify or
modify, if necessary, conclusions and recommendations in this report.
If any or all of these inspections to verify site geotechnical
conditions are not performed by this firm, liability for the safety
and stability of the project cannot be accepted by the undersigned.
In order to provide timely inspections, this firm should be
notified at least 48 hours in advance of excavation.
CLOSURE
The undersigned warrant that this report was prepared in
accordance with generally accepted principles and practice in the
field of engineering geology and soils engineering. This warranty is
in lieu of all other warranties, either expressed or implied.
The findings conclusions and recommendations reflect our best
estimate of soil and bedrock conditions based on the data obtained
from a limited subsurface exploration performed during the field
investigation. The conclusions and recommendations are based on
generally accepted engineering principles and practices. No further
warranties are implied nor made.
Due to the possible variability of soil and subsurface conditions
within the site, conditions may be encountered during grading and
development that differ from those presented herein. Should any
variations or unusual conditions become apparent during grading and
development, this office shall be contacted to evaluate these
conditions prior to continuation of work and to make any necessary
revisions to the recommendations.
This office shall be notified if changes of ownership occur of if
final plans for the site development indicate structure areas, type of
structures, or structural loading conditions differing from those
presented in this report.
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
Job No. 5676-P1-A7 June 3, 1987 -14-
If the site is not developed or grading does not begin within 24
months following the date of this report, further investigation may be
required to ensure that the surface or subsurfce conditions have not
changed.
Any charges for necessary review or updates will be at the
prevailing rate at the time the review work is performed.
-o0o-
AAKO
GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
APPENDIX A
TECHNICAL REFERENCES
AAKO;TBANC.
Job No. 5676-P1-A7 June 3, 1987 -15-
TECHNICAL REFERENCES
1. Barrows, Allen G., 1974, "A Review of the Geology and Earthquake
History of the Newport -Inglewood Structural Zone, Southern
California," Division of Mines and Geology, Special Report 114.
2. California Division of Mines and Geology, 3 February 1975,
"Recommended Guidelines for Determining the Maximum Credible and
Maximum Probable Earthquakes", C.D.M.G. Note Number 43.
3. Cleveland, George B., 1976, "Geology of the Northeast Part of the
Palos Verdes Hills, Los Angeles, California," Map Sheet 27,
Published by the California Division of Mines and Geology.
4. Greensfelder, R.W., "Maximum Credible Rock Acceleration From
Earthquakes in California", California Division of Mines and
Geology, Map Sheet 23.
5. Jennings, C.W., 1962, "Geologic Map of California, Olaf P.
Jenkins Edition, Long Beach Sheet", 1:250,000 scale, California
Division of Mines and Geology.
6. Jennings, C.W., 1968, "Geologic Map of California, Olaf P.
Jenkins Edition, Santa Ana Sheet", 1:250,000 scale, California
Division of Mines and Geology.
7. Jennings, C.W., 1962,"Geologic Map of California, Olaf P. Jenkins
Edition, Los Angeles Sheet", 1:250,000 scale, California Division
of Mines and Geology.
8. Jennings, C.W., 1962, "Geologic Map of California, Olaf P.
Jenkins Edition, Los Angeles Sheet", 1:250,000 scale, California
Division of Mines and Geology.
9. Ploessel, M.R., and Slosson, J.E., September 1974, "Repeatable
High Ground Accelerations from Earthquakes", California Geology.
10. Schnabel, P.B. and Seed, P.B., April, 1973, "Accelerations in
Rock for Earthquakes in the Western United States", Bulletin of
the Seismological Society of America, Vol. 63, No. 2, pp. 501-516
11. U.S.G.S., 1972 Revision, "Torrance, California" Quadrangle Map 7
Minute Series, Scale 1"=2000'.
12. Ziony, J.I., et. al., 1974, "Preliminary Map Showing Recency of
Faulting in Coastal Southern California," at 1:500,000 Scale,
Unite States Geological Survey Miscellaneous Field Studies Map
MF-585.
AAKO
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ENGINEERING
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APPENDIX B
DRAWINGS
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GEOTECHNICAL
ENGINEERING
CONSULTANTS. INC.
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GEOTECHNICAL
ENGINEERING
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APPENDIX C
FAULT LOCATION MAP
TABLE S-1
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LOCATION OF MAJOR FAULTS IN SOUTHERN CALIFORNIA
AND
EPICENTERS OF EARTHQUAKES OF MAGNITUDE 6.0 OR GREATER
Maximum
Credible
Fault Name Magnitude
Raymond 6.5
Sierra Madre 6.6
Yerdugo 6.5
Workman Hill 6.2
Malibu -Santa Monica 7.8
Whittier -Elsinore 7.6
San Fernando 6.6
Newport -Inglewood 7.1
Simi -Northridge 6.5
San Jacinto (Punch Bowl) 7.5
San Andreas (Central) 8.5
(Table S-1)
SELECTION OF MAXIMUM PROBABLE EARTHQUAKE MAGNITUDES AND
SITE SPECIFIC PEAK AND REPEATABLE BEDROCK ACCELERATIONS
Geologic and (1)
Seismologic Evidence
Estimated Maximum Recurrence Interval(2)
Magnitude Historic Design Magnitude
Range Magnitude 58 Year 188 Year
Distance Peak(3+5) Repeatable(3+6)
From Bedrock Bedrock
Site Acceleration Acceleration
3.4 - 6.8 3.8 5.5 6.8 29 Miles -NE 8.87g
6.8 - 6.5(4) None 6.8 6.5 34 Miles -NE 8.88g
4.5 - 6.8 3.8 5.5 6.8 29 Miles-N 8.87g
3.5 - 5.5 3.8 5.8 6.8 26 Miles -NE 1.889
4.6 - 6.8 3.8 5.5 6.8 21 Miles -SW 8.18g
5.5 - 6.5 5.8 6.8 6.5 25 Miles -NE 8.13g
6.8 - 6.5 6.4 6.8 6.5 41 Miles-N 8.83g
6.8 - 6.7 6.3 6.8 6.5 11 Miles -NE 8.32g
4.5 - 6.8 4.3 5.5 6.8 36 Miles -NW 8.84g
6.8 - 7.5 7.8 6.5 7.8 53 Miles -NE 8.87g
7.5 - 8.5 8.8+ 7.5 8.8 55 Miles -NE 8.12g
(1) From historic data and judgmental determination based on
geologic relationships of fault type, trace, length,
and recurrence interval data.
(2) Based an data presented combined with judgment.
(3) Acceleration based on 58 year interval design magnitude.
(4) Larger magnitude event associated with reverse fault.
(5) Fro. Schnable and Seed, 1978.
(6) Fro. Ploessel and Slosson, 1974.
0.859
8.85g
8.85g
8.85g
8.17g
8.88g
8.82g
8.21g
8.83g
8.85g
8.88g
TABLE S-1
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APPENDIX D
PLOT PLAN
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CONSULTANTS. INC.