890, Augment the existing riding ri, Studies & ReportsDist. Office 12.02
PCA B372001/A304
Telephone: (626) 458-4925
Tract / Parcel Map
Site Address
Geologist
Soils Engineer
County of Los Angeles Department of Public Works
Geotechnical and Materials Engineering Division
GEOLOGIC AND SOILS ENGINEERING REVIEW SHEET
900 S. Fremont Avenue, Alhambra, CA 91803
1 Middleridge Lane South
Norcal Engineering
Lot(s)
Location
Developer/Owner
Engineer/Arch.
Review of: ROUGH GRADING AND FINAL GEOTECHNICAL REPORTS
Grading P.C. No.:
Rolling Hills
Sheet 1 of 1
Parent Tract
APN 7569-020-007
Popovich
Bolton
1602190004 For: Grading for arena, dressage and lunging ring
Geologic Report(s) Dated:
Soils Engineering Report(s) Dated:
Geotechnical Report(s) Dated:
References:
5/15/17, 12/20/16
Action: Based on the above referenced reports, rough grading is recommended for approval from a geotechnical standpoint for
the issuance of building permits with the following conditions.
1. Do not submit building plans to the Geotechnical and Materials Engineering Division for structures on the pads created
by the subject grading, provided code requirements and the consultant's recommendations are followed.
2. Foundation excavations must be inspected and approved by the consulting geologist/engineer prior to the placing of steel
or concrete.
Prepared by
William Man
Soils Section
ChaFTes Nestle
Geology Section
Date
6/7/17
Please complete a Customer Service Survey at htto://dow.lacountv.aov/ao/amedsurvev
NOTICE: Public safety, relative to geotechnical subsurface exploration, shall be provided in accordance with current codes for excavations, inclusive
of the Los Angeles County Code, Chapter 11.48, and the State of California, Title 8, Construction Safety Orders.
P:\gmepub\Development Review'JCombined Reviews\12.02 City of Rolling Hills\1 Middleridge Ln South, Rolling Hills FGR-2.docx
Dist. Office 12.02
PCA B372001/A304
Telephone: (626) 458-4925
Tract / Parcel Map
Site Address
Geologist
Soils Engineer
County of Los Angeles Department of Public Works
Geotechnical and Materials Engineering Division
GEOLOGIC AND SOILS ENGINEERING REVIEW SHEET
900 S. Fremont Avenue, Alhambra, CA 91803
1 Middleridge Lane South
Norcal Engineering
Lot(s)
Location
Developer/Owner
Engineer/Arch.
Review of: ROUGH GRADING AND FINAL GEOTECHNICAL REPORTS
Rolling Hills
Sheet 1 of 1
Parent Tract
APN 7569-020-007
Popovich
Bolton
Grading P.C. No.: 1602190004 For: Grading for arena, dressage and lunging ring
Geologic Report(s) Dated:
Soils Engineering Report(s) Dated:
Geotechnical Report(s) Dated:
References:
5/15/17, 12/20/16
Action: Based on the above referenced reports, rough grading is recommended for approval from a geotechnical standpoint for
the issuance of building permits with the following conditions.
1. Do not submit building plans to the Geotechnical and Materials Engineering Division for structures on the pads created
by the subject grading, provided code requirements and the consultant's recommendations are followed.
2. Foundation excavations must be inspected and approved by the consulting geologist/engineer prior to the placing of steel
or concrete.
Prepared by1191.59
William Man oF FJ.,
Soils Section
Chafes Nestle
Geology Section
Date
6/7/17
Please complete a Customer Service Survey at htto://dow.lacountv.aov/ao/amedsurvev
NOTICE: Public safety, relative to geotechnical subsurface exploration, shall be provided in accordance with current codes for excavations, inclusive
of the Los Angeles County Code, Chapter 11.48, and the State of Califomia, Title 8, Construction Safety Orders.
P:\ymepub\Development Review\!Combined Reviews\12.02 City of Rolling Hills\1 Middleridge Ln South, Rolling Hills FGR-2.docx
•
•
•
•
•
NorCal Engineering
Soils and Geotechnical Consultants
10641 Humbolt Street Los Alamitos, CA 90720
(562) 799-9469 Fax (562) 799-9459
December 20, 2016 Project Number 18559-15
Gregory and Adriana Popovich
1 Middleridge Lane South
Rolling Hills, California 90274
2ECEVED
JUL U / 2017
City of Rolling Hills
By
RE: Report of Geotechnical Observation and Testing of Rough Grading
Operations - Proposed Equestrian Dressage and Lunging Ring for Single
Family Residence - Located at 1 Middleridge Lane South, in the City of
Rolling Hills, California
• Dear Mr. and Mrs. Popovich:
Pursuant to your request, this firm has provided this geotechnical report to summarize
the observation and testing performed during rough grading operations at the above
referenced project. The geotechnical aspects were conducted in accordance with our
• report titled "Geotechnical Engineering Investigation", dated January 5, 2016, Project
Number 18559-15. Our geotechnical services pertaining to the grading of the project
development are summarized in the subsequent sections of this report.
•
•
•
Site Grading
The purpose of the grading operations was for the placement of fill to provide structural
support of the proposed development. All vegetation and demolition debris was stripped
and removed from the fill area prior to the placement of any fill soils. The upper low
density surface soils area were removed to competent native material, the exposed
surface scarified, moisture conditioned and then recompacted to a minimum of 90%
relative compaction. Soils within the lower slope area were properly benched and
compacted during grading operations.
•
• December 20, 2016 Project Number 18559-15
Page 2
A drain line was installed adjacent to the bench vertical cut located approximately
• halfway up the slope. The drain consisted of 4-inch diameter perforated PVC pipe and
% inch diameter gravel wrapped with filter fabric. Solid PVC pipe was connected to the
drain and extended out to the face of the slope. The approximate location of the drain is
shown on the attached plan.
•
•
Fill soils placed were compacted to a minimum 90% of the laboratory standard in lifts
not in excess of eight inches in thickness. The maximum depth of fill soils placed was
approximately 10 feet. A track mounted loader was utilized for compaction control. A
water hose provided moisture control. Our services did not include any surveying of
excavation bottoms, building corners, or subgrade elevations during grading operations.
• Laboratorv/Field Testing
The relative compaction was determined by Sand Cone Method (ASTM: D1556-07) and
by the Drive Tube Method (ASTM: D 2937-10). The maximum density of the on -site
soils was obtained by the laboratory standard (ASTM: D1557-12) and results are shown
• on Table I. Tests were performed a minimum of every 500 cubic yards placed and
every two feet in depth of fill placed. A summary of the compaction tests of the rough
grading operations are described in Appendix B with locations shown on the
accompanying plan.
•
•
•
•
A. Expansion index tests in accordance with ASTM D 4829-11 were performed on
remolded samples of the upper soils to determine the expansive characteristics
and to provide any necessary recommendations for reinforcement of the slabs -
on -grade and the foundations. Results of these tests are provided on Table II in
Appendix A.
B. Soluble sulfate tests in accordance with California Test Method 417 were
performed on representative soils samples to estimate the potential for corrosion
of concrete in contact with theon-site soils. Results are provided on Table III in
Appendix A.
NorCal Engineering
•
• December 20, 2016 Project Number 18559-15
Page 3
•
•
•
Foundation Design
Any proposed foundations may be designed utilizing an allowable bearing capacity of
1,500 psf for a minimum depth of 24 inches below lowest adjacent grade. A one-third
increase may be used when considering short term loading from wind and seismic
forces. All foundations located near adjacent slopes shall meet all setback criteria per
the latest California Building Code (CBC) standards. All foundations shall have a
minimum 12 inch width for any one story structure. All continuous foundations shall be
reinforced with a minimum of two, No. 4 bars, top and bottom. A representative of this
firm shall inspect all foundation excavations prior to pouring concrete.
Slab Design
All concrete slabs shall be at least four inches in thickness reinforced a minimum of No.
3 bars spaced sixteen inches apart in each direction, positioned in the center of the slab,
and placed on approved subgrade soils. Prior to placement of slabs, the subgrade soils
shall be moisture conditioned to 3% above optimum moisture content to a depth of
eighteen inches.
A vapor barrier (6-mil minimum thickness) should be covered with one inch of approved
sand and underlain by six inches of sand beneath all floor slabs sensitive to the
infiltration of moisture. All concrete slab areas to receive floor coverings should be
• moisture tested to meet all manufacturer requirements prior to placement.
•
•
•
Expansive Soil
Due to the expansive nature of the subsurface soils, special attention should be given to
the project design and maintenance. The attached Expansive Soil Guidelines should be
reviewed by the engineers, architects, owner, maintenance personnel and other
interested parties and considered during the design of the project and future property
maintenance.
NorCal Engineering
•
•
•
•
December 20, 2016 Project Number 18559-15
Page 4
Corrosion Design Criteria
Representative samples of the surficial soils revealed negligible sulfate concentrations.
Therefore, all concrete in contact with on site soils shall be designed in accordance with
Table 4.3.1 of ACI 318 Building Code and Commentary. Sulfate test results may be
found on the attached Table III.
Limitations
It should be noted that our work does not warrant or guarantee that the contractor
responsible for each phase of the project has performed his work in accordance with the
project specifications.
We appreciate this opportunity to be of service to you. If you have any further
• questions, please do not hesitate to contact the undersigned.
Respectfully submitted,
NORCAL ENGINEERING
Keith D. Tucker
Project Engineer
R.G.E. 841
•
•
•
•
Walter K. Mott
Project Manager
•
NorCal Engineering
• December 20, 2016 Project Number 18559-15
Page 5
Expansive Soil Guidelines
•
The following expansive soil guidelines are provided for your project. The intent of
these guidelines is to inform you, the client, of the importance of proper design and
maintenance of projects supported on expansive soils. You, as the owner or other
interested party, should be warned that you have a duty to provide the
• information contained in the soil report including these guidelines to your design
engineers, architects, landscapers and other design parties in order to enable
them to provide a design that takes into consideration expansive soils.
•
In addition, you should provide the soil report with these guidelines to any property
manager, lessee, property purchaser or other interested party that will have or assume
the responsibility of maintaining the development in the future.
Expansive soils are fine-grained silts and clays which are subject to swelling and
contracting. The amount of this swelling and contracting is subject to the amount of
fine-grained clay materials present in the soils and the amount of moisture either
• introduced or extracted from the soils. Expansive soils are divided into five categories
ranging from "very low" to "very high". Expansion indices are assigned to each
classification. If the expansion index of the soils on your site, is 21 or higher, you have
expansive soils. The classifications of expansive soils are as follows:
•
•
Classification of Expansive Soil*
Expansion Index Potential Expansion
0-20 Very Low
21-50 Low
51-90 Medium
91-130 High
Above 130 Very High
*From Table 18A-I-B of California Building Code (1988)
When expansive soils are compacted during site grading operations, care is taken to
• place the materials at or slightly above optimum moisture levels and perform proper
compaction operations. Any subsequent excessive wetting and/or drying of expansive
soils will cause the soil materials to expand and/or contract. These actions are likely to
cause distress of foundations, structures, slabs -on -grade, sidewalks and pavement over
the life of the structure. It is therefore imperative that even after construction of
• improvements, the moisture contents are maintained at relatively constant levels,
allowing neither excessive wetting or drying of soils.
•
NorCal Engineering
•
• December 20, 2016 Project Number 18559-15
Page 6
•
•
Evidence of excessive wetting of expansive soils may be seen in concrete slabs, both
interior and exterior. Slabs may lift at construction joints producing a trip hazard or may
crack from the pressure of soil expansion. Wet clays in foundation areas may result in
lifting of the structure causing difficulty in the opening and closing of doors and windows,
as well as cracking in exterior and interior wall surfaces. In extreme wetting of soils to
depth, settlement of the structure may eventually result. Excessive wetting of soils in
landscape areas adjacent to concrete or asphaltic pavement areas may also result in
expansion of soils beneath pavement and resultant distress to the pavement surface.
Excessive drying of expansive soils is initially evidenced by cracking in the surface of
the soils due to contraction. Settlement of structures and on -grade slabs may also
eventually result along with problems in the operation of doors and windows.
• Projects located in areas of expansive clay soils will be subject to more movement and
"hairline" cracking of walls and slabs than similar projects situated on non -expansive
sandy soils. There are, however, measures that developers and property owners may
take to reduce the amount of movement over the life the development. The following
guidelines are provided to assist you in both design and maintenance of projects on
expansive soils:
•
•
•
•
• Drainage away from structures and pavement is essential to prevent
excessive wetting of expansive soils. Grades of at least 3% should be
designed and maintained to allow flow of irrigation and rain water to
approved drainage devices or to the street. Any "ponding" of water adjacent
to buildings, slabs and pavement after rains is evidence of poor drainage; the
installation of drainage devices or regrading of the area may be required to
assure proper drainage. Installation of rain gutters is also recommended to
control the introduction of moisture next to buildings. Gutters should
discharge into a drainage device or onto pavement which drains to roadways.
• Irrigation should be strictly controlled around building foundations, slabs and
pavement and may need to be adjusted depending upon season. This
control is essential to maintain a relatively uniform moisture content in the
expansive soils and to prevent swelling and contracting. Over -watering
adjacent to improvements may result in damage to those improvements.
NorCal Engineering makes no specific recommendations regarding
landscape irrigation schedules.
• Planting schemes for landscaping around structures and pavement should
be analyzed carefully. Plants (including sod) requiring high amounts of water
may result in excessive wetting of soils. Trees and large shrubs may actually
extract moisture from the expansive soils, thus causing contraction of the
fine-grained soils.
NorCal Engineering
• December 20, 2016 Project Number 18559-15
Page 7
•
•
•
•
•
•
•
•
•
• Thickened edges on exterior slabs will assist in keeping excessive moisture
from entering directly beneath the concrete. A six-inch thick or greater
deepened edge on slabs may be considered. Underlying interior and exterior
slabs with 6 to 12 inches or more of non -expansive soils and providing
presaturation of the underlying clayey soils as recommended in the soil
report will improve the overall performance of on -grade slabs.
• Increase the amount of steel reinforcing in concrete slabs, foundations and
other structures to resist the forces of expansive soils. The precise amount
of reinforcing should be determined by the appropriate design engineers
and/or architects.
• Recommendations of the soil report should always be followed in the
development of the project. Any recommendations regarding presaturation
of the upper subgrade soils in slab areas should be performed in the field
and verified by the Soil Engineer.
NorCal Engineering
•
•
•
•
•
•
•
APPENDICES
(In order of appearance)
Appendix A — Laboratory Tests
Table 1— Maximum Density Tests
Table II — Expansion Index
Table III - Sulfate Tests
Appendix B — Summary of Compaction Tests
Site Plan
• Summary of Compaction Tests
•
•
•
NorC al Engineering
•
•
•
•
•
Appendix A
•
•
•
•
•
•
NorC al Engineering
•
• December 20, 2016 Project Number 18559-15
Page 8
•
•
•
•
•
•
•
•
•
TABLE I
MAXIMUM DENSITY TESTS
(ASTM: D1557-121
Optimum Maximum"Dry
Sample Classification Moisture Density (Ibs./cu.ft.)
I Clayey SILTSTONE 17.0 97.0
II Silty CLAY 16.5 105.0
III Silty CLAY 19.0 94.0
TABLE II
EXPANSION INDEX TESTS
(U.B.C. STD. 4829-111
Expansion
Sample Classification Index
Pad Subgrade Silty CLAY 83
TABLE III
SULFATE TESTS
Sample Sulfate (% by Weight)
Pad Subgrade 0.010
NorCal Engineering
•
•
•
•
•
•
•
•
•
•
•
Appendix B
NorC al Engineering
•
•
•
•
•
•
•
•
1 "=50'.
o-
P O S, ,I2-
ytiy S' `r�0
//‘QF
x599.4
• '
•
BRUSH
N�o
y3o
.555
50
EXISTING EASEMENT
EPENTSFOR
ROAD
EXISTING
RESIDENCE
,43.3
54
r
G
� =APPROXIMATE LIMITS OF GRADING
(E),
LUNGING
RING
544. i
CONC
CONC
I
L=349.95'
m r_y
35.7 o
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
POPOV ICH
PROJECT 18559-15 JJ DATE DECEMBER 2016
\l
EXISTING ___TRAVLLED ROADWAY
(At 7-377-150.40
(
EX STING TRAVELED ROAD'
LOCATION OF COMPACTION TESTS
•
• December 20, 2016 Project Number 18559-15
Page 9
SUMMARY OF COMPACTION TEST RESULTS
• Date of Test Percent Unit Wt. Relative Soil Test
Test No. Location Depth Moisture lbs./cu.ft. Compaction Type S/D
7/21/16 101 Site Grading 8.0-8.5 19.0 89.4 92 I D
7/21/16 102 Site Grading 4.0-4.5 18.1 90.2 93 I D
7/21/16 103 Site Grading 4.0-4.5 19.8 92.6 95 I D
• 7/21/16 104 Site Grading 4.0-4.5 17.7 82.3 95 I S
7/21/16 105 Site Grading 6.0-6.5 18.6 87.6 90 I D
7/21/16 106 Site Grading 3.0-3.5 16.9 89.1 92 I D
7/22/16 107 Site Grading 2.0-2.5 18.7 98.6 94 II D
7/22/16 108 Site Grading 2.0-2.5 18.4 95.2 91 II S
• 7/25/16 109 Site Grading 0.0-0.5 14.9 97.5 93 II D
7/25/16 110 Site Grading 0.0-0.5 16.4 97.8 93 II S
7/26/16 111 Site Grading 10.0710.5 18.4 91.2 94 I D
7/26/16 112 Site Grading 10.0-10.5 18.1 91.5 93 I S
7/26/16 113 Site Grading 10.0-10.5 18.7 89.3 92 I D
• 7/27/16 114 Site Grading 8.0-8.5 21.4 86.1 92 III D
7/27/16 115 Site Grading 8.0-8.5 20.6 88.3 94 III D
7/28/16 116 Site Grading 8.0-8.5 19.5 87.8 93 III S
7/28/16 117 Site Grading 8.0-8.5 21.0 88.0 94 III D
7/28/16 118 Site Grading 6.0-6.5 19.3 87.6 93 III S
• 7/29/16 119 Site Grading 4.0-4.5 20.8 86.4 92 III D
7/29/16 120 Site Grading 8.0-8.5 20.6 86.7 92 III S
7/29/16 121 Site Grading 10.0-10.5 17.7 91.3 94 I D
7/29/16 122 Site Grading 8.0-8.5 18.5 89.5 92 I D
8/1/16 123 Site Grading 2.0-2.5 19.0 87.6 90 I D
• 8/1/16 124 Site Grading 2.0-2.5 18.9 88.4 91 I S
8/2/16 125 Site Grading 9.0-9.5 20.1 86.9 92 III D
8/2/16 126 Site Grading 6.0-6.5 20.9 87.9 94 III D
8/2/16 127 Site Grading 0.0-0.5 20.3 86.6 92 III D
8/2/16 128 Site Grading 0.0-0.5 21.0 88.7 94 III S
• 8/4/16 129 Site Grading 6.0-6.5 21.7 85.5 91 III D
8/4/16 130 Site Grading 3.0-3.5 20.5 86.4 92 III D
8/5/16 131 Site Grading 8.0-8.5 18.9 91.6 94 I D
8/5/16 132 Site Grading 8.0-8.5 18.7 89.7 92 I S
•
•
**Retest of failing tests after area reworked
S= Sand Cone Method
D= Drive Tube Method
NorCal Engineering
•
• December 20, 2016 Project Number 18559-15
Page 10
SUMMARY OF COMPACTION TEST RESULTS
• Date of Test Percent Unit Wt. Relative Soil Test
Test No. Location Depth Moisture lbs./cu.ft. Compaction Type S/D
8/5/16 133 Site Grading 8.0-8.5 18.8 90.0 93 I D
8/5/16 134 Site Grading 8.0-8.5 18.6 90.5 93 I S
8/8/16 135 Site Grading 6.0-6.5 21.6 88.8 94 III D
• 8/8/16 136 Site Grading 4.5-5.0 22.0 86.7 96 III S
8/9/16 137 Site Grading 4.0-4.5 23.5 87.4 93 III D
8/9/16 138 Site Grading 3.5-4.0 20.9 82.7 88 III D
8/9/16 138A** Site Grading 3.5-4.0 19.1 86.8 92 III D
8/11/16 139 Site Grading 2.0-2.5 21.2 88.4 94 III S
• 8/11/16 140 Site Grading 2.0-2.5 21.4 89.1 95 III D
8/11/16 141 Site Grading 2.0-2.5 20.5 87.8 93 III S
8/15/16 142 Site Grading 0.0-0.5 16.1 87.5 90 I D
8/15/16 143 Site Grading 0.0-0.5 17.8 91.6 94 I S
8/15/16 144 Site Grading 0.0-0.5 16.9 92.4 95 I D
• 8/15/16 145 Site Grading 0.0-0.5 17.4 87.7 90 I D
8/15/16 146 Site Grading 0.0-0.5 17.6 95.2 91 II D
8/15/16 147 Site Grading 0.0-0.5 17.6 96.2 92 II S
•
•
•
•
•
**Retest of failing tests after area reworked
S= Sand Cone Method
D= Drive Tube Method
NorCal Engineering
•
Geotechnical Engineering Investigation
Proposed Equestrian Dressage and Lunging Rings
for Single Family Residence
1 Middleridge Lane South
Rolling Hills, California
RECNEIVED
JUL 0 7 2016
City of Rolling Hills
By
Gregory and Adriana Popovich
1 Middleridge Lane South
Rolling Hills, California 90274
January 5, 2016
Project Number 18559-15
NorCal Engineering
Soils and Geotechnical Consultants
10641 Humbolt Street Los Alamitos, CA 90720
(562)799-9469 Fax (562)799-9459
January 5, 2016 Project Number 18559-15
Gregory and Adriana Popovich
1 Middleridge Lane South
Rolling Hills, California 90274
RE: Geotechnical Engineering Investigation - Proposed Equestrian
Dressage and Lunging Rings for Single Family Residence - Located at 1
Middleridge Lane South, in the City of Rolling Hills, California
Dear Mr. and Mrs. Popovich:
Pursuant to your request, this firm has performed a Geotechnical Engineering
Investigation for the above referenced project in accordance with your approval of
proposal dated October 30, 2015. The purpose of this investigation is to evaluate the
subsurface conditions of the subject site and to provide recommendations for the
proposed equestrian dressage and lunging rings for single family residence.
The scope of work included the following: 1) site reconnaissance; 2) review of available
geologic literature and city building files 3) subsurface geotechnical exploration and
sampling; 4) laboratory testing; 5) engineering analysis of field and laboratory data; and
6) preparation of a geotechnical engineering report. It is the opinion of this firm that the
proposed development is feasible from a geotechnical standpoint provided that the
recommendations presented in this report are followed in the design and construction of
the project.
J 1 January 5, 2016 Project Number 18559-15
Page 2
1.0 Project Description
It is proposed to construct equestrian dressage ring and lunging ring for a single family
residence as shown on the attached Site Plan (Figure 1). The (66' x 198') dressage and
(60' diameter) lunging rings will consist of grading a relatively level pad by constructing 2
to 1 (horizontal to vertical) cut and fill slopes ranging in height from 10 to 30 in height
(Figures 2 and 3). The lunging ring may consist of a prefabricated covered metal
structure. Other improvements will include horse trails, wood fencing and landscaping.
Final building plans shall be reviewed by this firm prior to submittal for city approval to
determine the need for any additional study and revised recommendations pertinent to
the proposed development, if necessary.
2.0 Site Description
The site consists of a 6.33-acre residential property located at the southwest corner of
Middleridge Lane South and Middleridge Road, in the City of Rolling Hills. The generally
triangular shaped lot is elongated in a northeast to southwest direction with topography
of the gently rolling natural hillside descending from north to south. The property is
currently occupied by single family residence, horse stables and corrals with associated
improvements.
3.0 Site Exploration
The investigation consisted of the placement of five (5) subsurface exploratory trenches
by a backhoe to depths ranging between 4 and 13 feet below current ground elevations.
The explorations were visually classified and logged by a geologist with locations of the
subsurface explorations shown on the attached Site Plan. The exploratory borings
revealed the existing earth materials to consist of a colluvium and Altamira Formation
bedrock. A detailed description of the subsurface conditions is listed on the excavation
logs in Appendix A. It should be noted that the transition from one soil type to another
as shown on the borings logs is approximate and may in fact be a gradual transition.
The soils encountered are described as follows:
NorCal Engineering
I I January 5, 2016 Project Number 18559-15
Page 3
Colluvium: An undisturbed native soil classifying as a dark brown, silty CLAY with
bedrock fragments were encountered directly at the surface. These soils were
noted to be firm and moist. The upper 1 to 3 feet was noted to be disturbed and
soft.
Bedrock: The Altamira Shale member of the Monterey Formation was
encountered below the colluvium at a depth ranging between 1% and 12 feet below
ground surface. This bedrock consists of moderately to well bedded Diatomaceous
Shale to clayey Siltstone which was noted to be moderately hard to hard and moist.
The overall engineering characteristics of the earth material were relatively uniform with
each excavation. No groundwater was encountered and no caving occurred to the
depth of our excavations.
4.0 Laboratory Tests
Relatively undisturbed samples of the subsurface soils were obtained to perform
laboratory testing and analysis for direct shear, consolidation tests, and to determine in -
place moisture/densities. These relatively undisturbed ring samples were obtained by
driving a thin -walled steel sampler lined with one inch long brass rings with an inside
diameter of 2.42 inches into the undisturbed soils. Bulk bag samples were obtained in
the upper soils for expansion index tests and maximum density tests. All test results are
included in Appendix B, unless otherwise noted.
4.1 Field moisture content (ASTM: D 2216-10) and the dry density of the ring samples
were determined in the laboratory. This data is listed on the logs of explorations.
4.2 Maximum density tests (ASTM: D-1557-12) were performed on typical samples of the
upper soils. Results of these tests are shown on Table I.
4.3 Expansion index tests (ASTM: D 4829-11) were performed on remolded samples of
the upper soils. Results of these tests are provided on Table II.
NorCal Engineering
1 January 5, 2016 Project Number 18559-15
Page 4
4.4 Atterberg Limits (ASTM: D 4318-10) consisting of liquid limit, plastic limit and plasticity
index were performed on representative soil samples. Results are shown on Table III.
4.5 Corrosion tests consisting of sulfate, pH, resistivity and chloride analysis to determine
potential corrosive effects of soils on concrete and underground utilities were performed
in the laboratory. Test results are provided on Table IV.
4.6 Direct Shear tests (ASTM: D 3080-11) were performed on undisturbed and disturbed
samples of the subsurface soils. The test is performed under saturated conditions at
loads of 1,000 lbs./sq.ft., 2,000 lbs./sq.ft., and 3,000 lbs./sq.ft. with results shown on
Plates A and B.
4.7 Consolidation tests (ASTM: D 2435-11) were performed on undisturbed samples to
determine the differential and total settlement which may be anticipated based upon the
proposed loads. Water was added to the samples at a surcharge of one KSF and the
settlement curves are plotted on Plates C and D.
5.0 Geologic Conditions
The property is located within the Peninsular Ranges geomorphic province of California.
The Peninsular Ranges province extends from the Los Angeles Basin southeast to Baja
California and from the Pacific Ocean eastward to the Coachella Valley and Colorado
Desert. The province consists of numerous northwest to southeast -trending mountain
ranges and valleys that are geologically controlled by several major active faults. More
specifically, the subject property is situated on a northeast -trending flat ridgeline
between Agua Manga Canyon to the northwest and Sepulveda Canyon to the
southeast.
NorCal Engineering
! T
January 5, 2016 Project Number 18559-15
Page 5
Geologic mapping by Dibblee (1999) indicates that the area is underlain by Miocene
Altamira Shale of the Monterey Formation. Dibblee describes the bedrock as mostly
light gray shale and mudstone with tuffaceous and dolomitic strata throughout. Our site -
specific subsurface exploration encountered colluvium (slope wash) overlying the
Altamira Shale.
The colluvium encountered in our trenches ranged in thickness from about 2 feet to
about 12 feet, and consists of dark brown silty clays with siltstone fragments. The
bedrock consists of thinly bedded, moderately hard siltstone. Bedding orientations
measured in our test pits are about horizontal to dipping gently to the northwest and
northeast. Bedding orientations are more varied on the slope descending to Agua
Magna Canyon, indicating local gentle folding of the siltstone. No signs of instability
were observed in the areas of the proposed improvements. The Seismic Hazards Zone
Map for the Torrance Quadrangle does not classify the slope as having the potential for
ground displacement.
The most prominent geologic structural elements in the Palos Verdes Peninsula are the
northwest -trending Palos Verdes and Cabrillo faults with reported Holocene offshore
surface rupture and Late Quaternary onshore surface rupture. The Palos Verdes fault is
mapped roughly one and one half miles to the northeast of the property. A queried
branch of the Cabrillo fault is shown terminating roughly three quarters of a mile
southwest of the site.
6.0 Seismicity Evaluation
The site is located in an area of high regional seismicity and a maximum horizontal
ground acceleration may occur from a Magnitude 7.1 earthquake along the Palos
Verdes fault zone, which is located Tess than 2 kilometers away. Ground shaking
originating from earthquakes along other active faults in the region is expected to induce
lower horizontal accelerations due to smaller anticipated earthquakes and/or greater
distances to other faults.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 6
The seismic design of the project has been updated to the latest 2010 ASCE 7-10 (with
July 2013 errata) standards and the mapped seismic ground motions were provided by
using the Java based program available from the United States Geological Survey
(USGS) website: htto://aeohazards.uses.aov/desianmaps/us/application.php. The site
is categorized as Seismic Design Category D in accordance the 2013 California Building
Code (CBC). The earthquake design parameters are on the following page.
Seismic Desian Parameters
Site Location Latitude 33.775°
Longitude -118.350°
Site Class D
Risk Category I/II/III
Maximum Spectral Response Acceleration Ss 1.609g
Si 0.620g
Adjusted Maximum Acceleration SMs 1.609g
SM, 0.930g
Design Spectral Response Acceleration Parameters SDS 1.073g
SD1 0.620g
7.0 Liquefaction Evaluation
Our analysis indicates the potential for liquefaction at this site is considered to be very
low due to shallow bedrock and the depth of groundwater in excess of 50 feet. The site
is not located in an area which is mapped by the State of California Seismic Hazards
Mapping Act as potentially susceptible to liquefaction. Thus, no additional investigation
regarding liquefaction was performed and the design of the proposed construction in
conformance with the latest Building Code provisions for earthquake design and the
following recommendations are expected to provide mitigation of ground shaking
hazards that are typical to Southern California.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 7
8.0 Conclusions and Recommendations
Based upon our evaluations, the proposed residential development is acceptable from a
geotechnical engineering standpoint. By following recommendations and guidelines set
forth in this report, the proposed structures and minor grading across the building pad
area will be safe from landslides, slippage or settlements under the anticipated design
loadings and conditions. The proposed development and grading shall meet all
requirements of the City Building Ordinance and will not impose any adverse effect on
property outside of the subject site.
The following recommendations are based upon geotechnical conditions encountered in
our field investigation and laboratory data. Therefore, these surface and subsurface
conditions could vary across the site. Variations in these conditions may not become
evident until the commencement of grading operations and any unusual conditions
which may be encountered in the course of the project development may require the
need for additional study and revised recommendations. Adequate drainage away from
the structures, pavement and slopes should be provided at all times.
It is recommended that site inspections be performed by a representative of this firm
during all grading and construction of the development to verify the findings and
recommendations documented in this report. The following sections present a
discussion of geotechnical related requirements for specific design recommendations of
different aspects of the project.
8.1 Site Grading Recommendations
All vegetation and/or demolition debris shall be removed and hauled from proposed
building area prior to the start of grading operations. Existing vegetation shall not be
mixed or disced into the soils. Any removed soils may be reutilized as compacted fill
once any deleterious material or oversized materials (in excess of eight inches) is
removed. Grading operations shall be performed in accordance with the attached
"Specifications for Compacted Fill Operations".
NorCal Engineering
•
January 5, 2016 Project Number 18559-15
Page 8
All disturbed surface soils (about 1% to 3 feet below existing ground surface) shall be
removed to competent colluvium and/or bedrock, the exposed surface scarified to a
depth of 12 inches, brought to within 2% of optimum moisture content and compacted to
a minimum of 90% of the laboratory standard (ASTM: D-1557-07) prior to placement of
any additional compacted fill soils, foundations, slabs -on -grade and pavement. Grading
may need to extend a minimum of five horizontal feet outside the edges of foundations
or equidistant to the depth of fill placed, whichever is greater.
If building areas with foundations encounter transition between the underlying bedrock
and colluvium/engineered fill, additional overexcavation of the bedrock to provide a two
feet thick blanket of engineered fill will be required to mitigate the potential of differential
settlement. Otherwise, all foundations will require to be deepened entirely into the
underlying bedrock material.
It is possible that isolated areas of undiscovered fill not described in this report are
present on site. If found, these areas should be treated as discussed earlier. A diligent
search shall also be conducted during grading operations in an effort to uncover any
underground structures, irrigation or utility lines. If encountered, these structures and
lines shall be either removed or properly abandoned prior to the proposed construction.
8.2 Temporary Excavations
Temporary unsurcharged excavations in the existing site materials up to 4 feet high may
be made at a vertical gradient unless cohesionless soils are encountered. In areas
where soils with little or no binder are encountered, where adverse geological conditions
are exposed, or where excavations are adjacent to existing structures, shoring, slot -
cutting, or flatter excavations may be required. Additional recommendations regarding
specific excavations may be calculated once typical detail sections are made available.
All excavations shall be made in accordance with the requirements of CAL -OSHA and
other public agencies having jurisdiction. Care should be taken to provide or maintain
adequate lateral support for all adjacent improvements and structures at all times during
the grading operations and construction phase.
NorCal Engineering
> January 5, 2016 Project Number 18559-15
Page 9
8.3 Foundation Design
Any proposed foundations may be designed utilizing an allowable bearing capacity of
1,500 psf for a minimum depth of 24 inches below lowest adjacent grade. A one-third
increase may be used when considering short term loading from wind and seismic
forces. All foundations located near adjacent slopes shall meet all setback criteria per
the latest California Building Code (CBC) standards. All foundations shall have a
minimum 12 inch width for any one story structure. All continuous foundations shall be
reinforced with a minimum of two, No. 4 bars, top and bottom. A representative of this
firm shall inspect all foundation excavations prior to pouring concrete.
8.4 Settlement Analysis
Resultant pressure curves for the consolidation tests are shown on Plates C and D.
Computations utilizing these curves and the recommended safe bearing capacities
reveal that the foundations will experience settlements on the order of 3/ inch and
differential settlements of Tess than % inch.
8.5 Lateral Resistance
The following values may be utilized in resisting lateral Toads imposed on the structure.
Requirements of the California Building Code should be adhered to when the coefficient
of friction and passive pressures are combined.
Coefficient of Friction - 0.35
Equivalent Passive Fluid Pressure = 200 lbs./cu.ft.
Maximum Passive Pressure = 2,000 lbs./sq.ft.
The passive pressure recommendations are valid only for approved compacted fill soils
and/or native soils/bedrock.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 10
8.6 Retaining Wall Design Parameters
Active earth pressures against retaining walls will be equal to the pressures developed
by the following fluid densities. These values are for granular backfill material placed
behind the walls at various ground slopes above the walls.
Surface Slope of Retained Materials Equivalent Fluid
(Horizontal to Vertical) Density (Ib./cu.ft.)
Level 30
5 to 1 35
4 to 1 38
3to 1 40
2to 1 45
Any applicable short-term construction surcharges and seismic forces should be added
to the lateral pressure values. An equivalent fluid pressure of 45 pcf may be utilized for
the restrained wall condition with a level grade behind the wall.
All walls shall be waterproofed as needed and protected from hydrostatic pressure by a
reliable permanent subdrain system. The granular backfill to be utilized immediately
adjacent to the basement walls shall consist of an approved granular soils with a sand
equivalency greater than 30. The subsurface drainage system shall consist of 4-inch
diameter perforated PVC pipe encased with gravel and wrapped with filter fabric.
The seismic -induced lateral soil pressure may be computed using a triangular pressure
distribution with the maximum value at the top of the wall. The maximum lateral
pressure of (20 pcf) H, where H is the height of the retained soils above the wall footing
should be utilized in final design of retaining walls. Sliding resistance values and
passive fluid pressures given in our referenced report may be increased by 1/3 during
short-term wind and seismic loading conditions.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 11
8.7 Slab Design
All concrete slabs shall be at least four inches in thickness reinforced a minimum of No.
3 bars spaced sixteen inches apart in each direction, positioned in the center of the slab,
and placed on approved subgrade soils. Prior to placement of slabs, the subgrade soils
shall be moisture conditioned to 3% above optimum moisture content to a depth of
eighteen inches.
A vapor barrier (6-mil minimum thickness) should be covered with one inch of approved
sand and underlain by six inches of sand beneath all floor slabs sensitive to the
infiltration of moisture. All concrete slab areas to receive floor coverings should be
moisture tested to meet all manufacturer requirements prior to placement.
8.8 Corrosion Design Criteria
Representative samples of the surficial soils, typical of the subgrade soils expected to
be encountered within foundation excavations and underground utilities were tested for
corrosion potential. The minimum resistivity value obtained for the samples tested is
representative of an environment that may be severely corrosive to metals. The soil pH
value was considered mildly alkaline and may have a significant effect on soil
corrosivity. Consideration should be given to corrosion protection systems for buried
metal such as protective coatings, wrappings or the use of PVC where permitted by
local building codes.
According to Table 4.3.1, ACI 318 Building Code and Commentary, these contents
revealed negligible levels of sulfate exposure. Therefore, a Type II cement according to
latest CBC specifications may be utilized for building foundations at this time. Additional
sulfate tests shall be performed at the completion of site grading to assure that these
soils are consistent with the recommendations stated in this design. Test results may
be found on the attached Table III.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 12
8.9 Utility Trench and Excavation Backfill
Trenches from installation of utility lines and other excavations may be backfilled with
on -site soils or approved imported soils compacted to a minimum of 90% relative
compaction. All utility lines shall be properly bedded with clean sand having a sand
equivalency rating of 30 or more. This bedding material shall be thoroughly water jetted
around the pipe structure prior to placement of compacted backfill soils.
8.10 Expansive Soil
Due to the expansive nature of the subsurface soils, special attention should be given to
the project design and maintenance. The attached Expansive Soil Guidelines should be
reviewed by the engineers, architects, owner, maintenance personnel and other
interested parties and considered during the design of the project and future property
maintenance.
9.0 Closure
The recommendations and conclusions contained in this report are based upon the soil
conditions uncovered in our test excavations. No warranty of the soil condition between
our excavations is implied. NorCal Engineering should be notified for possible further
recommendations if unexpected to unfavorable conditions are encountered during
construction phase.
It is the responsibility of the owner to ensure that all information within this report is
submitted to the Architect and appropriate Engineers for the project. This firm should
have the opportunity to review the final plans to verify that all our recommendations are
incorporated.
This report and all conclusions are subject to the review of the controlling authorities for
the project. Our representative should be present during the grading operations and
construction phase to certify that such recommendations are complied within the field.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 13
A preconstruction conference should be held between the developer, general contractor,
grading contractor, city inspector, architect, and soil engineer to clarify any questions
relating to the grading operations and subsequent construction. Our representative
should be present during the grading operations and construction phase to certify that
such recommendations are complied within the field.
This geotechnical investigation has been conducted in a manner consistent with the
level of care and skill exercised by members of our profession currently practicing under
similar conditions in the Southern California area. No other warranty, expressed or
implied is made.
We appreciate this opportunity to be of service to you. If you have any further
questions, please do not hesitate to contact the undersigned.
Respectfully submitted,
NORCAL ENGINEER
Keith D. Tucker
Project Engineer
R.G.E. 841
Scott D. Spensiero
Project Manager
No. 841
Exp. 12/31/1 O
GAIO
NorCal Engineering
Andrew St
Project Geologi
C.E.G. 1648
,sokED GE'04
<4,Q�f.
W R. So����
a No.1648 t'
CERTIFIED
ENGINEERING
GEOLOGIST
\�'9i OF CAUF(�'e.
January 5, 2016 Project Number 18559-15
Page 14
References
1. State of California Seismic Hazard Zones, Torrance Quadrangle, Official Map
Released: March 25, 1999, compiled by California Geological Survey
2. Geologic Map of the Palos Verdes Peninsula and Vicinity, Redondo Beach,
Torrance and San Pedro Quadrangles, Los Angeles County, California,
published by the Dibblee Geologic Formation, by Thomas W. Dibblee, Jr., 1999
3. Geologic Map of California Long Beach Sheet, published by the California
Division of Mines and Geology, 1962
4. California Division of Mines and Geology, 2008, Guidelines for Evaluating and
Mitigating Seismic Hazards in California: Special Publication 117A.
5. California Building Code, 2013.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 15
SPECIFICATIONS FOR PLACEMENT OF COMPACTED FILL
Excavation
Any existing low density soils and/or saturated soils shall be removed to competent
natural soil under the inspection of the Soils Engineering Firm. After the exposed
surface has been cleansed of debris and/or vegetation, it shall be scarified until it is
uniform in consistency, brought to the proper moisture content and compacted to a
minimum of 90% relative compaction (in accordance with ASTM: D-1557-07).
In any area where a transition between fill and native soil or between bedrock and soil
are encountered, additional excavation beneath foundations and slabs will be necessary
in order to provide uniform support and avoid differential settlement of the structure.
Material for Fill
The on -site soils or approved import soils may be utilized for the compacted fill provided
they are free of any deleterious materials and shall not contain any rocks, brick,
asphaltic concrete, concrete or other hard materials greater than eight inches in
maximum dimensions. Any import soil must be approved by the Soils Engineering firm
a minimum of 24 hours prior to importation of site.
Placement of Compacted Fill Soils
The approved fill soils shall be placed in layers not excess of six inches in thickness.
Each lift shall be uniform in thickness and thoroughly blended. The fill soils shall be
brought to within 2% of the optimum moisture content, unless otherwise specified by the
Soils Engineering firm. Each lift shall be compacted to a minimum of 90% relative
compaction (in accordance with ASTM: D-1557-07) and approved prior to the placement
of the next layer of soil. Compaction tests shall be obtained at the discretion of the Soils
Engineering firm but to a minimum of one test for every 500 cubic yards placed and/or
for every 2 feet of compacted fill placed.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 16
The minimum relative compaction shall be obtained in accordance with accepted
methods in the construction industry. The final grade of the structural areas shall be in
a dense and smooth condition prior to placement of slabs -on -grade or pavement areas.
No fill soils shall be placed, spread or compacted during unfavorable weather conditions.
When the grading is interrupted by heavy rains, compaction operations shall not be
resumed until approved by the Soils Engineering firm.
Grading Observations
The controlling governmental agencies should be notified prior to commencement of any
grading operations. This firm recommends that the grading operations be conducted
under the observation of a Soils Engineering firm as deemed necessary. A 24 hour
notice must be provided to this firm prior to the time of our initial inspection.
Observation shall include the clearing and grubbing operations to assure that all
unsuitable materials have been properly removed; approve the exposed subgrade in
areas to receive fill and in areas where excavation has resulted in the desired finished
grade and designate areas of overexcavation; and perform field compaction tests to
determine relative compaction achieved during fill placement. In addition, all foundation
excavations shall be observed by the Soils Engineering firm to confirm that appropriate
bearing materials are present at the design grades and recommend any modifications to
construct footings.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 17
Expansive Soil Guidelines
The following expansive soil guidelines are provided for your project. The intent of
these guidelines is to inform you, the client, of the importance of proper design and
maintenance of projects supported on expansive soils. You, as the owner or other
interested party, should be warned that you have a duty to provide the
information contained in the soil report including these guidelines to your design
engineers, architects, landscapers and other design parties in order to enable
them to provide a design that takes into consideration expansive soils. In
addition, you should provide the soil report with these guidelines to any property
manager, lessee, property purchaser or other interested party that will have or assume
the responsibility of maintaining the development in the future.
Expansive soils are fine-grained silts and clays which are subject to swelling and
contracting. The amount of this swelling and contracting is subject to the amount of
fine-grained clay materials present in the soils and the amount of moisture either
introduced or extracted from the soils. Expansive soils are divided into five categories
ranging from "very low" to "very high".
Expansion indices are assigned to each classification and are included in the laboratory
testing section of this report. If the expansion index of the soils on your site, as stated in
this report, is 21 or higher, you have expansive soils. The classifications of expansive
soils are as follows:
Classification of Expansive Soil*
Expansion Index Potential Expansion
0-20 Very Low
21-50 Low
51-90 Medium
91-130 High
Above 130 Very High
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 18
When expansive soils are compacted during site grading operations, care is taken to
place the materials at or slightly above optimum moisture levels and perform proper
compaction operations. Any subsequent excessive wetting and/or drying of expansive
soils will cause the soil materials to expand and/or contract. These actions are likely to
cause distress of foundations, structures, slabs -on -grade, sidewalks and pavement over
the life of the structure. It is therefore imperative that even after construction of
improvements, the moisture contents are maintained at relatively constant levels,
allowing neither excessive wetting or drying of soils.
Evidence of excessive wetting of expansive soils may be seen in concrete slabs, both
interior and exterior. Slabs may lift at construction joints producing a trip hazard or may
crack from the pressure of soil expansion. Wet clays in foundation areas may result in
lifting of the structure causing difficulty in the opening and closing of doors and windows,
as well as cracking in exterior and interior wall surfaces. In extreme wetting of soils to
depth, settlement of the structure may eventually result. Excessive wetting of soils in
landscape areas adjacent to concrete or asphaltic pavement areas may also result in
expansion of soils beneath pavement and resultant distress to the pavement surface.
Excessive drying of expansive soils is initially evidenced by cracking in the surface of
the soils due to contraction. Settlement of structures and on -grade slabs may also
eventually result along with problems in the operation of doors and windows.
Projects located in areas of expansive clay soils will be subject to more movement and
"hairline" cracking of walls and slabs than similar projects situated on non -expansive
sandy soils. There are, however, measures that developers and property owners may
take to reduce the amount of movement over the life the development. The following
guidelines are provided to assist you in both design and maintenance of projects on
expansive soils:
• Drainage away from structures and pavement is essential to prevent
excessive wetting of expansive soils. Grades should be designed to the
latest Building Code and maintained to allow flow of irrigation and rain water
to approved drainage devices or to the street.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 19
• Any "ponding" of water adjacent to buildings, slabs and pavement after rains
is evidence of poor drainage; the installation of drainage devices or regrading
of the area may be required to assure proper drainage. Installation of rain
gutters is also recommended to control the introduction of moisture next to
buildings. Gutters should discharge into a drainage device or onto pavement
which drains to roadways.
• Irrigation should be strictly controlled around building foundations, slabs and
pavement and may need to be adjusted depending upon season. This
control is essential to maintain a relatively uniform moisture content in the
expansive soils and to prevent swelling and contracting. Over -watering
adjacent to improvements may result in damage to those improvements.
NorCal Engineering makes no specific recommendations regarding
landscape irrigation schedules.
• Planting schemes for landscaping around structures and pavement should
be analyzed carefully. Plants (including sod) requiring high amounts of water
may result in excessive wetting of soils. Trees and large shrubs may actually
extract moisture from the expansive soils, thus causing contraction of the
fine-grained soils.
• Thickened edges on exterior slabs will assist in keeping excessive moisture
from entering directly beneath the concrete. A six-inch thick or greater
deepened edge on slabs may be considered. Underlying interior and exterior
slabs with 6 to 12 inches or more of non -expansive soils and providing
presaturation of the underlying clayey soils as recommended in the soil
report will improve the overall performance of on -grade slabs.
• Increase the amount of steel reinforcing in concrete slabs, foundations and
other structures to resist the forces of expansive soils. The precise amount
of reinforcing should be determined by the appropriate design engineers
and/or architects.
NorCal Engineering
January 5, 2016 Project Number 18559-15
Page 20
• Recommendations of the soil report should always be followed in the
development of the project. Any recommendations regarding presaturation
of the upper subgrade soils in slab areas should be performed in the field
and verified by the Soil Engineer.
NorCal Engineering
ET LOT AREA
1.
.s8p0=- _- _= _•;n`�_ =xssnuG w62S: tRntL.���
!;oc E ��� ,-i' •-, �- / .
57 �i�� - f--:.r-•_'` Yam-, - �,a /� /•�
%.— 1543.E r . 6 J / / //�+"r -..f
-
� — FIi'1'( A.._,..0,
Qf��' t)�� �/ — _________/"'
'` J •' I'—/ ' k� t,,.,
,..i �EX{STING DIRT PATHWAY-,... �- , i y._: -- - 'y�''� t
'� ti / i 733 # pia. .,ARE:JA. ACCESS flASI `i^'L=jam
r' r' `Y—(E) mAr.rEns - .�"- „j '`
PAD NO. I
EXISTING
STABLE
•saga j,
' (E) POWER POLE— •`~^ �C�.'._ �cs_
-
Qom
i
a.
1 I I i
PFU tJO, t�
S"=
-``J c,� E7n51�J0 FOUN LAIN
/ 1/
(EOVERHEAD POWER LINE�
/ \\ %I1 1 1,—
£xiSTING cAZEBQ/
120 SO. rr, maH
�£ W\EF NorCal Engineering
�� _ SOILS AND GEOTECHNICAL CONSULTANTS
PROJECT
DATE
b. 35
— (E) UMW VAULT
Qcol
Tm
/11) �rl� " I
E} (//
STORM DRAIN
tt 7-/
EX!.
15/
LEGEND
CoU uvium
Monterey Formation
Geologic Contact
Strike and Dip of Bedding
Horizontal Bedding
Exploratory Trench
1 INCH = 60 FEET
GRAPHIC SCALE
0 30 SO
90
SITE PLAN
z
FIGURE 1
. EXISTING
RESIDENCE
-580
-540
EXISTING GRADE
0 40'
I }
Tm
LESTIMATED BEDDING
T-2
DRESSAGE RING
PROPOSED GRADE
Qcol
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
T13
SECTION A -A'
PL
MIDDLERIDGE LANE SOUTH
FIGURE 2
PROJECT 18559-15 DATE DECEMBER 2015
PL
••580
>540
40'
PROPOSED GRADE
Tm
-ESTIMATED BEDDING
DRESSAGE RING
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
EXISTING GRADE
SECTION B-B'
B'
FIGURE 3
PROJECT 18559-15 I DATE
DECEMBER 2015
-580
-540
PL
0
40'
LUNGING RING
PROPOSED GRADE
EXISTING GRADE
..✓-��f"mil
----� Tm
Qcol
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
ESTIMATED BEDDING
SECTION C-C'
FIGURE 4
PROJECT 18559-15 I DATE DECEMBER 2015
January 5, 2016 Project Number 18559-15
Page 21
List of Appendices
(in order of appearance)
Appendix A - Loa of Excavations
• Log of Trenches T-1 to T-5
Appendix B - Laboratory Tests
• Table I - Maximum Dry Density
• Table II — Expansion
• Table III — Atterberg Limits
• Table IV — Corrosion
• Plates A and B - Direct Shear
• Plates C and D - Consolidation
NorCal Engineering
January 5, 2016 Project Number 18559-15
Appendix A
NorCal Engineering
COARSE
GRAINED
SOILS
MORE THAN
50% OF
MATERIAL
IS LARGER
THAN NO.
200 SIEVE
SIZE
FINE
GRAINED
SOILS
MORE THAN
50% OF
MATERIAL
IS SMALLER
THAN NO.
200 SIEVE
SIZE
MAJOR DIVISION
GRAVEL
AND
GRAVELLY
SOILS
MORE THAN
50% OF
COARSE
FRACTION
RETAINED ON
NO. 4 SIEVE
SAND
AND
SANDY
SOILS
MORE THAN
50% OF
COARSE
FRACTION
PASSING ON
NO. 4 SIEVE
SILTS
AND
CLAYS
SILTS
AND
CLAYS
CLEAN GRAVELS
(LITTLE OR NO
FINES)
GRAVELS
WITH FINES
(APPRECIABLE
AMOUNT OF
FINEST
CLEAN SAND
(LITTLE OR NO
FINES)
SANDS WITH
FINE
(APPRECIABLE
AMOUNT OF
FINES)
LIQUID LIMIT
I FSS THAN .rift
LIQUID LIMIT
GREATER THAN
50
HIGHLY ORGANIC SOILS
GRAPHIC
SVMRf
0 00
0 106
IMMO
•
LETTER
RVManI
GW
GP
GM
GC
SW
SP
SM
SC
ML
CL
OL
MH
CH
OH
PT
TYPICAL. DESCRIPTIONS
WELL -GRADED GRAVELS, GRAVEL.
SAND MIXTURES, LITTLE OR NO FINES
POORLY -GRADED GRAVELS,
GRAVEL -SAND MIXTURES, LITTLE
OR NO FINES
SILTY GRAVELS, GRAVEL -SAND -
SILT MIXTURES
CLAYEY GRAVELS, GRAVEL -SAND -
CLAY MIXTURES
WELL -GRADED SANDS, GRAVELLY
SANDS, LITTLE OR NO FINES
POORLY -GRADED SANDS, GRAVEL-
LY SANDS, LITTLE OR NO FINES
SILTY SANDS, SAND -SILT
MIXTURES
CLAYEY SANDS, SAND -CLAY
MIXTURES
INORGANIC SILTS AND VERY FINE
SANDS, ROCK FLOUR, SILTY OR
CLAYEY FINE SANDS OR CLAYEY
SILTS WITH SLIGHT PLASTICITY
INORGANIC CLAYS OF LOW TO
MEDIUM PLASTICITY, GRAVELLY
CLAYS, SANDY CLAYS, SILTY
CLAYS. LEAN CLAYS
ORGANIC SILTS AND ORGANIC
SILTY CLAYS OF LOW PLASTICITY
INORGANIC SILTS, MICACEOUS OR
DIATOMACEOUS FINE SAND OR
SILTY SOILS
INORGANIC CLAYS OF HIGH
PLASTICITY, FAT CLAYS
ORGANIC CLAYS OF MEDIUM TO
HIGH PLASTICITY, ORGANIC SILTS
PEAT. HUMUS, SWAMP SOILS WITH
HIGH ORGANIC CONTENTS
NOTE: DUAL SYMBOLS ARE USED TO INDICATE BORDERLINE SOIL CLASSIFICATIONS
UNIFIED SOIL CLASSIFICATION SYSTEM
NorCal Engineering
KEY:
■
m
EI
Indicates 2.5-inch Inside Diameter. Ring Sample.
Indicates 2-inch OD Split Spoon Sample (SPT).
Indicates Shelby Tube Sample.
Indicates No Recovery.
Indicates SPT with 140# Hammer 30 in. Drop.
Indicates Bulk Sample.
Indicates Small Bag Sample.
Indicates Non -Standard
Indicates Core Run.
COMPONENT DEFINITIONS
COMPONENT
Boulders
Cobbles
Gravel
Coarse gravel
Fine gravel
Sand
Coarse sand
Medium sand
Fine sand
Silt and Clay
SIZE RANGE
Larger than 12 in
3into 12in
3 in to No 4 (4.5mm )
3into3/4in
3/4 in to No 4 ( 4,5mm )
No. 4 (4.5mm ) to No, 200 ( 0.074mm )
No. 4 ( 4,5 mm ) to No. 10 ( 2.0 mm )
No. 10 ( 2.0 mm ) to No. 40 ( 0.42 mm )
No, 40(0.42mm)toNo, 200(0.074mm)
Smaller than No. 200 ( 0.074 mm )
COMPONENT PROPORTIONS
DESCRIPTIVE TERMS RANGE OF PROPORTION
Trace
Few
Little
Some
And
1-5%
5 - 10%
10 - 20%
20 - 35%
35 - 50%
MOISTURE CONTENT
DRY
DAMP
MOIST
WET
Absence of moisture, dusty,
dry to the touch.
Some perceptible
moisture; below optimum
No visible water; near optimum
moisture content
Visible free water, usually
soil is below water table.
RELATIVE DENSITY OR CONSISTENCY VERSUS SPT N -VALUE
Density
Very Loose
Loose
Medium Dense
Dense
Very Dense
COHESIONLESS SOILS
N ( blows/ft )
NorCal Engineering
0 to 4
4 to 10
10 to 30
30 to 50
over 50
Consistency
COHESIVE SOILS
N (blows/ft) Approximate
Undrained Shear
Strength (psf)
Very Soft 0 to 2
Soft 2 to 4
Medium Stiff 4 to 8
Stiff 8 to 15
Very Stiff 15 to 30
Hard over 30
< 250
250 - 500
500 - 1000
1000 - 2000
2000 - 4000
'> 4000
Gregory and Adriana Popovich
18559-15
Log of Trench T-1
Boring Location: 1 Middleridge Lane South
Date of Drilling: 12/1/15
Drilling Method: Backhoe
Hammer Weight:
Surface Elevation: Not Measured
Depth Lith-
(feet) ology
— o
— 5
re —I
ILL
— 20
E
0
a
0
• — • 25
f,
d
F
U
0I
— 30
a
0
• _
— 35
Material Description
Groundwater Depth: Not Encountered
Drop:
COLLUVIUM
Silty CLAY
Dark brown, firm, moist with bedrock fragments
Upper foot disturbed and soft
Boring completed at depth of 6'
NorCal Engineering
Samples Laboratory
w L w C �-
a c� w zc 0
I— m o 'o ❑ y a o
ci ❑ N
1
Gregory and Adriana Popovich
18559-15
Log of Trench T-2
Boring Location: 1 Middleridge Lane South
Date of Drilling: 12/1/15
Drilling Method: Backhoe
Hammer Weight:
Surface Elevation: Not Measured
Depth Lith-
(feet) ology
• — 1 0
0
0
✓ i
'
co
W
o —15
a
• —
0
0
O —
o.
0)
O _
lL
— 20
E
0
O —
0
0
O
• —25
�_
0
— 30
— 35
Material Description
Groundwater Depth: Not Encountered
Drop:
COLLUVIUM
Silty CLAY
Dark brown, soft, moist with siltstone fragments
BEDROCK
Clayey SILTSTONE
Grey -brown, moderately hard, moist, thinly bedded, siliceous
B-N55E, 18NW
\B-N40E, 15NW
Boring completed at depth of 6'
NorCal Engineering
Samples
co
d OQ.
H co
0
Laboratory
L. C
7 G>
• e0 —
0 p0 a. c
N .
22.7 73.3
23.4 83.3
2
Gregory and Adriana Popovich
18559-15
Log of Trench T-3
Date: 1/4/2016
0
N
Boring Location: 1 Middleridge Lane South
Date of Drilling: 12/1/15
Drilling Method: Backhoe
Hammer Weight:
Surface Elevation: Not Measured
Depth Lith-
(feet) ology
— o
— 5
—10
'o —15
re
a-
0
0.
U
5i
W — 20
E
O
.0
0
tn
▪ — 25
• -
— 35
GWi not encountered
Material Description
Groundwater Depth: Not Encountered
Drop:
COLLUVIUM
Silty CLAY
Dark brown, firm, moist with bedrock fragments
Upper one foot disturbed and soft
Highly weathered and partially reworked siltstone below 10'
BEDROCK
\ClaySILTSTONE
ey
Light brown, hard, moist, moderately bedded
B-N40E, 15-18NW
Boring completed at depth of 13'
NorCal Engineering
Samples Laboratory
d 3 c • w = y.
a c . Z'� m m
H mo 0 05 D.
V N
■
■
18.3 86.9
22.2 91.3
■ 23.9 88.0
3
Gregory and Adriana Popovich
18559-15
Log of Trench T-4
Boring Location: 1 Middleridge Lane South
Date of Drilling: 12/1/15
Drilling Method: Backhoe
Hammer Weight:
Surface Elevation: Not Measured
Depth Lith-
(feet) ology
— 0
— 5
0
N
0'
0
N -
N
-
0
W
2-15
re
a
a
0
0
0 —
0
N _
0
u _
LL
— 20
E
O
O -
O _
0
• —25
0
N -
F -
.5
0 —
0
O
— 30
— 35
Material Description
COLLUVIUM
Silty CLAY
Dark brown, soft, moist with bedrock fragments
BEDROCK
Clayey SILTSTONE
Light brown, moderately hard to hard, moist, moderately bedded
B-N3OW, 4SW
B-Horizontal
Boring completed at depth of 4'
Groundwater Depth: Not Encountered
Drop:
NorCal Engineering
■
Laboratory
w ° agi
QC cu c
5 a) 0. o
5
12.3 84.6
4
s
Gregory and Adriana Popovich
18559-15
Boring Location: 1 Middleridge Lane South
Date of Drilling: 12/1/15
Drilling Method: Backhoe
Hammer Weight: 1 Drop:
Surface Elevation: Not Measured
Depth Lith-
(feet) ology
—0
—5
-
—10
0
YI
01
to —
N
co
—
U
o' —15
0.
0.
0
0
t
a
0)
N
5 _
IL
— 20
E
0
o —
0
CO
— 25
o
0
—
a
—
V _
rn
— 30
— 35
GWT not encountered
Material Description
Groundwater Depth: Not Encountered
COLLUVIUM
Silty CLAY
Dark brown, firm, moist with bedrock fragments
Upper one foot disturbed and soft
BEDROCK
Diatomaceous Shale
Light grey, hard, moist
NB -Horizontal
Boring completed at depth of 10.5'
NorCal Engineering
Log of Trench T-5
Samples Laboratory
m 3 c w c>
T o y �'C rya
F- m o 5 0 0 a o
C.)N
■
0
15.6 86.3
18.7 88.4
■ 28.6 72.3
5
January 5, 2016 Project Number 18559-15
Appendix B
NorCal Engineering
. • January 5, 2016 Project Number 18559-15
TABLE I
MAXIMUM DENSITY TESTS
Optimum
Sample Classification Moisture
T-2 @ 2' Silty CLAY 16.5
T-2 @ 5' Clayey Siltstone 17.0
TABLE II
EXPANSION INDEX TESTS
Maximum Dry
Density (lbs./cu.ft.)
105.0
97.0
Expansion
Soil Type Classification Index
T-2 @ 2' Silty CLAY 85
T-2 @ 5' Clayey Siltstone 91
TABLE III
ATTERBERG LIMITS
Sample Liquid Limit Plastic Limit Plasticity Index
T-3 @ 2' 44 24 20
T-3 @ 5' 42 25 17
T-3 @ 12' 47 26 21
TABLE IV
CORROSION TESTS
Sample pH Electrical Resistivity (ohm -cm) Sulfate (%' Chloride (Dom)
T-2 @ 2' 6.8 697 0.013 237
T-2 @ 5' 6.7 986 0.006 203
% by weight
NorCal Engineering
Sample No. T2@2'
Sample Type: Undisturbed/Saturated
Soil Description: Silty Clay w/ Some Bedrock Fragments
Normal Stress
Peak Stress
Displacement
Residual Stress
Displacement
In Situ Dry Density
In Situ Water Content
Saturated Water Content
Strain Rate
4000
3500
3000
N 2500
a
to
,� 2000
1)
L
cc
1500
1000
500
0
1 2 3
(psf) 1000 2000 3000
(psf) 816 1320 1656
(in) 0.150 0.200 0.225
(psf) 792 1308 1656
(in.) 0.250 0.250 0.250
(pcf) 73.3 73.3 73.3
(%) 22.7 22.7 22.7
(%) 47.8 47.8 47.8
(in/min) 0.020 0.020 0.020
3000
2500
N 2000
a
0
1500
`a
1000
1
I
III
I
I
/--
I
,----13
I
I
I
I
I
Peak Strt
Residual
3 ksf
2 ksf
-11 ksf
4 0 6 0 8.0 10.0 12.0
Axial Strain (%)
• Peak Stress
• Residual Stress
0 (Degree) C (psf)
ss 22 420
Stress 23 390
0 500 1000 1500 2000 2500 3000 3500 4000
Normal Stress (psf)
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
Gregory & Adrian Popovich
PROJECT NUMBER: 18559-15 DATE: 12/15/2015
DIRECT SHEAR TEST
ASTM D3080
Plate A
Sample No. T4@3'
Sample Type: Undisturbed/Saturated
Soil Description: Clayey Siltstone
1 2 3
Normal Stress (psf) 1000 2000 3000
Peak Stress (psf) 840 1296 1956
Displacement (in.) 0.100 0.200 0.200
Residual Stress (psf) 744 1284 1932
Displacement (in.) 0.250 0.250 0.250
In Situ Dry Density (pef) 84.6 84.6 84.6
In Situ Water Content (%) 12.3 12.3 12.3
Saturated Water Content (%) 36.6 36.6 36.6
Strain Rate (in/min) 0.020 0.020 0.020
Shear Stress (psfl
4000
3500
3000
2500
2000
1500
1000
500
d/
I
I
I/
V I
0
0 500
3000
2500
ca 2000
x 1500
N
w 1000
500
3 ksf
2 ksf
1 ksf
0
0.0 2.0 4.0 6.0 8.0 10.0 12.0
Axial Strain (%)
♦ Peak Stress
• Residual Stress
0 (Degree) C (psf)
Peak Stress 29 250
Residual Stress 30 130
1000 1500 2000 2500 3000 3500 4000
Normal Stress (psf)
NorCal Engineering DIRECT SHEAR TEST
SOILS AND GEOTECHNICAL CONSULTANTS ASTM D3080
Gregory & Adrian Popovich Plate B
PROJECT NUMBER: 18559-15 DATE: 12/15/2015
Vertical Pressure
(kips/sq.ft.)
Sample Height (inches)
Consolidation
(percent)
0.125 1.0000 0.0
0.25 0.9960 0.4
0.5 0.9930 0.7
1 0.9890 1.1
1 0.9895 1.1 .,z3
2 0.9825 1.8
cs
4 0.9705 3.0 l
8 0.9540 4.6 ccn
0.25 0.9690 3.1
Sample No.
1.02
1.01
1.00 -�
0.99
0.98
0.97
0.96
0.95
0.94
in'
i 0.93
Date Tested: 12/7/2015 c
Sample: T2 " 0.92
Z
Depth: 5' 0'
= 0.91
a)
oa
E 0.90
m
to
0.89
0.88
0.87
0.86
0.85
0.84
T2 Depth 5'
0.83•Clayey Siltstone
Dry Density: 83.3 pcf
Initial Moisture Content: 23.4 %
0.82 • Saturated Moisture Content: 37.6 %
Saturated at 1 kip/sq.ft.
0.81 .
0.1
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
Gregory & Adrian Popovich
PROJECT NUMBER: 18559-15 DATE: 12/15/2015
FI
I I
I �
I I
Date 12/15/2015
• In -Situ Moisture Content
0 Saturated
_
1 10
Vertical Pressure (kips/sq.ft.)
CONSOLIDATION TEST
ASTM D2435
Plate C
Vertical Pressure
(kips/sq.ft.)
Sample Height (inches)
Consolidation
(percent)
0.125 1.0000 0.0
0.25 0.9960 0.4
0.5 0.9920 0.8
1 0.9860 1.4
1 1.0030 -0.3 .S
2 0.9945 0.6 -412
cs
4 0.9775 2.3
8 0.9520 4.8 ea
0.25 0.9880 1.2
Sample No. T5 Depth 10'
1.02
1.01 1
1.00 --■
0.99
0.98
0.97
0.96
a)
a)
Date Tested: 12/7/2015 5
Sample: T5
t
Depth: 10'
x
a)
E
m
0
0.95
0.94
0.93
0.92
0.91
0.90
0.89
0.88
0.87
0.86
0.85
0.84
0.83 -
0.82 •
0.81
0.1
Diatomaceous Siltstone
Dry Density: 72.3 pcf
Initial Moisture Content: 28.6 %
Saturated Moisture Content: 48.7 %
Saturated at 1 kip/sq.ft.
NorCal Engineering
SOILS AND GEOTECHNICAL CONSULTANTS
Gregory & Adrian Popovich
PROJECT NUMBER: 18559-15 DATE: 12/15/2015
Date 12/15/2015
■ In -Situ Moisture Content
O Saturated
I '
1 10
Vertical Pressure (kips/sq.ft.)
CONSOLIDATION TEST
ASTM D2435
Plate D