HomeMy WebLinkAboutAttachment 11 Preliminary Water Quality Management Plan
PRELIMINARY
WATER QUALITY MANAGEMENT PLAN
(WQMP)
For:
“Orange Corp Yard Workforce Housing“
637 W. Struck Ave, Orange, CA
Prepared for:
C & C Development Co., LLC
14211 Yorba St., S-200
Tustin, CA 92780
(714) 288-7600
Prepared by:
So Cal Civil Solutions, Inc.
Mike J-S Ma RCE No. C68130
26131 Via Oceano
Mission Viejo, CA 92691
(949) 322-3657
Prepared on 03/30/2020
Revised on “N/A”
____________________________ _________________________
Public Works Director Date
__________________________ ________________________
City Engineer Date
OWNER’S CERTIFICATION
WATER QUALITY MANAGEMENT PLAN
FOR
Orange Corp Yard Workforce Housing
This Water Quality Management Plan (WQMP) for the “Orange Corp Yard Workforce
Housing“ has been prepared for C & C Development Co., LLC . This WQMP is
intended to comply with the requirements of the City of Orange’s [Tract/Parcel Map #
2020-127, and/or Site Development Permit/Application # (to-be-provided)] requiring
preparation of a Water Quality Management Plan.
The undersigned, while it owns the subject property, is responsible for the
implementation of the provisions of this plan and will ensure that this plan is
amended as appropriate to reflect up-to-date conditions on the site consistent with
the City of Orange Local Implementation Plan (LIP), and the intent of NPDES Permit
and Waste Discharge Requirements for the City of Orange, County of Orange,
Orange County Flood Control District and the incorporated Cities of Orange County
within the Santa Ana Region.
This WQMP will be reviewed with the facility operator, facility supervisors,
employees, tenants, maintenance and service contractors, or any other party having
responsibility for implementing portions of this WQMP. Maintenance requirements
within Section V and Appendix D will be adhered to with particular emphasis on
maintaining the BMPs described within Sections IV and V. The Owner’s Annual Self
Certification Statement along with a BMP maintenance implementation table will be
submitted by June 30th every year following project completion. At least one copy of
the approved WQMP shall be available on the subject property in perpetuity.
Once the undersigned transfers its interest in the property, its successors-in-interest
shall bear the aforementioned responsibility to implement and amend the WQMP.
The City of Orange will be notified of the change of ownership and the new owner will
submit a new certification.
Signature: ____________________________Date:
Name: ______________________________
Title: _______________________________
Company: ______________________________________
Address: _______________________________________
Telephone Number: ________________________
Noce of Transfer of Responsibility
Water Quality Management Plan (WQMP)
WQMP Number – As assigned by the City of Orange:
Submission of this No ce of Transfer of Responsibility cons tutes no ce to the City that responsibility
for the Water Quality Management Plan (WQMP) for the subject property iden &ed below, and
implementa on of that plan, is being transferred from the Previous Owner (and his/her agent) of the
site (or por on thereof) to the New Owner, as further described below.
I.Previous Owner/ Responsible Party Informaon
Company/ Individual: Contact Person:
Street Address: Title:
City State Zip Phone:
II.Informaon about Site Relevant to WQMP
Name of Project:
Title of WQMP applicable to site:
Street Address of the site:
Date of Transfer of Responsibility:
III.New Owner/ Responsible Party Informaon
Company/ Individual: Contact Person:
Street Address: Title:
City State Zip Phone:
Preliminary WQMP for
Orange Corp Yard Workforce Housing
Table of Contents
I Discretionary Permit Number(s), Water Quality Condition Number(s) and
Conditions of Approval...............................................................................................1
II Project Description......................................................................................................2
III Site Description.........................................................................................................5
IV Best Management Practices....................................................................................7
IV.1 Site Design and Drainage Characteristics.....................................................8
IV.2 Source Control BMPs....................................................................................9
IV.3 Low Impact Development BMP Selection...................................................14
IV.4 Water Quality Credits...................................................................................24
IV.5 Alternative Compliance Plan.......................................................................24
IV.6 Vector Control..............................................................................................24
IV.7 Drainage Management Area (DMA)............................................................24
IV.8 Calculations.................................................................................................25
V Implementation, Maintenance and Inspection Responsibility for BMPs (O&M
Plan)............................................................................................................................28
VI Location Map, Site Plan, and BMP Details ...........................................................34
VII Educational Materials.............................................................................................37
Appendices
A.Conditions of Approval, City Council Resolution ______ dated ____ (N/A)
B.Educational Material
C.BMP Details
D.BMP Maintenance Information
E.Geotechnical Report
F.Watershed Maps
List of Tables
Table 1 Site Design BMPs
Table 2 Routine Non-Structural BMPs
Table 3 Routine Structural BMPs
Table 4 Hydrologic Source Control BMPs
Table 5 Infiltration BMPs
Table 6 Evapotranspiration, Rainwater Harvesting
Table 7 Biotreatment BMPs
Table 8 Frequency Inspection Matrix
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I Discretionary Permit Number(s), Water Quality Condition Number(s) and
Conditions of Approval
Tract No. 2020-127 Lot No. 2
Water Quality Conditions (WQMP conditions listed below)
A complete copy of the signed Conditions of Approval, City Council Resolution ______
dated _________ are included as Appendix A
(to-be-provided)
Conditions of Approval:
(to-be-provided)
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II Project Description
Planning Area: N/A
Project Size (ac): 2.67
Percent Change in Impermeable Surfaces : +64% (from 19% to 83%)
SIC Code (if applicable): N/A
Project Description
C & C Development Co., LLC is proposing a multi-family residential apartments
application along with lot lines adjustment to be located at 637 West Struck Avenue in
the City of Orange. The current site is vacant land, comprising approximately 2.7 acres
of an irregular-shaped land which is situated in the far east end of the 17.23-acre parcel
(APN 375-291-14) that is located at the northeast corner of the intersection at North
Batavia Street and West Struck Avenue (See Vicinity/Location Map in Section VI). The
site is bound on the north by commercial buildings, on the east by two sets of railroad
tracks with multi-family residential beyond, on the south by West Struck Avenue, a fully
improved roadway, followed by commercial buildings, and on the west by the remainder
of the City of Orange Corporate Yard.
The development proposes 62 affordable apartment homes in two – three story “walk
up” style buildings of similar size. There are 42 three-bedroom units and 20 one-
bedroom units along with a Leasing Office, Community Laundry Facility, 2 Community
Rooms with a common Kitchen, a computer lab and an onsite community service office.
There are a total of 133 parking stalls. The new community is walled & gated for added
security. Access to the site comes from the eastern most end of West Struck via the
existing cul de sac to the North and past Mary’s Kitchen.
In a summary, the net developed site acreage will approximately be 2.67 acres, among
which 2.23 acres will be hardscape (impervious) surfaces and 0.44 acres be softscape
(pervious) surfaces.
Project Purpose and Activities
The purpose of the project is to provide housing for residents. The primary project
activities include demolition, grading, and construction of building and infrastructure for
new multi-family apartment complex.
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Potential Storm Water Pollutants
Per Table 2.1 of the Technical Guidance Document, the expected project pollutants for
“attached residential development” include:
•Suspended-Solid/Sediment: from landscaping
•Nutrients: from landscaping
•Pathogens (Bacteria/Virus): from pavement runoff
•Pesticides: from landscaping
•Oil and Grease: from uncovered parking areas
•Trash and Debris: from trash areas
•Heavy metals: from parking areas
Hydrologic Conditions of Concern
In general, all downstream conveyance channels that will receive runoff from the project
are engineered, stabled and regularly maintained to ensure design flow capacity, and
no sensitive stream habitat areas will be affected. See OC Watershed Susceptibility
Analysis Map included in Appendix F.
The storm water travel path from the project is as:
Project Site => 36” RCP => 48” RCP => Collins Channel (E07) => Santa Ana
River Channel (E01) => Pacific Ocean (Huntington Beach)
In conclusion, an HCOC does not exist for the above receiving water bodies.
Post Development Drainage Characteristics
Under existing conditions, the project area would sheet flow westward to its nearby
warehouse (part of the “Orange Corporate Yard” area) and then drain southerly to the
36” RCP on West Struck Avenue. Therefore, the project will continue to drain its runoff
to the 36” RCP. In the proposed drainage plan, runoffs from development areas will be
conveyed via surface gutters and underground pipes to a storm water quality treatment
device first before discharge into the 36” RCP. And all off-site water will by-pass the
project
Commercial Projects
N/A.
Residential Projects
Yes. See Project Description above.
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Site Ownership and any Easements
The property will be a rental apartment community and therefore no homeowners or
property owner association will exist. The property will be owned by one entity (to be
formed limited liability partnership LLC) and professionally managed by a third party
property management company, to be determined. Long term maintenance of the
project’s stormwater facilities will be performed by the third party property management
and ensured by the Property Owner. There is no planned infrastructure that will be
transferred to any public agency.
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III Site Description
Reference Location Map: See Location Map included in Section V
Site Address: 637 W. Struck Ave, Orange, CA
Zoning: R-3 Residential
Predominant Soil type: D (See Soil Map included in Appendix F )
Pre-project percent pervious: 81% Post-project percent pervious: 17%
Pre-project percent impervious: 19% Post-project percent impervious: 83%
Site Characteristics
The subject site is vacant land. Under existing conditions, it is largely absent of
vegetation, with the exception of dense bushes and trees along the north boundary and
landscaping improvements and grass near the south side along West Struck Avenue.
The ground surface of most of the site is dirt covered in gravel and/or asphalt grindings
and asphalt, with some bare dirt present. Numerous items, trucks, tractors, trailers,
plant trimmings, light standards, k-rails, and other items associated with the site’s
current use as a city yard. In topography, the site area is relatively planar with a gentle
fall towards the west-southwest.
The hydrologic soil type is Group D, per the soil map from 1986 OC hydrology manual.
Per the project's preliminary Geotechnical Report (included in Appendix E), dated
February 25, 2020 and prepared by LOR Geotechnical Group, Inc., the site contains a
depth of 3-feet of fill materials, which consist of asphalt grindings underlain by silty sand
and lean clay with sand. Underlying the fill materials are the older alluvial materials
which consist of lean clay with sand and clayey sand with gravel, and lesser amounts
unit of sandy silt. Thus, the soil characteristics identified by the geotechnical firm
generally supports the presence of Group D soils on site.
Per the project's preliminary Geotechnical Report, groundwater was not encountered
within any of exploratory borings at the site. From the reference of nearby water well
data available from the State of California Department of Water Resources web site,
they concluded that groundwater is anticipated to lie at a depth greater than 100 feet at
the site.
In drainage, current surface runoff cross the site is generally as sheet flow to the west
and southwest. Two outlets are formed on the west edge of the site: one approximately
at the midpoint of the edge and the other at more to the north side. Per the as-built plan
for the Orange Corporate Yard, the project area was programed to drain westward and
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then drain southerly to a 36” RCP on West Struck Avenue. This 36” RCP originates
from the east under the AT&SF Rail Road. It crosses the railroad approximately at the
midpoint of the east edge of the site and then it immediately turns to the south and
traverses the west edge of the railroad right-of-way. Then it turns eastward to West
Struck Avenue and continues to traverse the West Struck Avenue. There is no other
existing drainage facility located within the project area.
Watershed Characteristics
Watershed: Lower Santa Ana River Watershed
Downstream Receiving Waters: Collins Channel (E07), Santa Ana River (E01), Pacific
Ocean – Huntington Beach
Water Quality Impairments (if applicable): Indicator Bacteria
Identify hydromodification susceptibility: No existence (See OC Watershed
Susceptibility Analysis Map included in Appendix F)
Identify Watershed Management Priorities: None
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IV Best Management Practices
Low Impact Development (LID) BMPs are required in addition to site design measures
and source controls to reduce pollutants in storm water discharges. LID BMPs are
engineered facilities that are designed to retain or biotreat runoff on the project site.
The current term MS4 Storm Water Permit requires the evaluation and use of LID
features using the following hierarchy of treatment: infiltration, evapotranspiration,
harvest/reuse, and biotreatment, etc. The following sections summarize the LID BMPs
proposed for the project in accordance with the LID BMPs hierarchy along with site
design and source control BMPS.
For this project, in general, infiltration BMPs should be applied cautiously as they would
potentially result in geotechnical risk to the nearby railroad tracks. Moreover, the site
has Soil Group “D”, which implies very low infiltration rate for on site soils. Thus. the
project will only pursue infiltration BMPs in landscape planting area along with ET from
the plants. In addition, the irrigation demand of the project does not support the harvest
use from rainwater. In conclusion, the project will turn to pursue the biotreatment BMPs
based the LID BMPs hierarchy.
In selecting biotreatment BMPs, considering the proposed site plan and drainage
characteristics of the site, we need a device with small footprint to be located near the
entrance from W. Struck Ave before the water discharging into the 36” RCP. After a
thorough evaluation, we chose the “Modular Wetland System” (MWS) as our structural
treatment BMPs for the project. MWS devices, which are a type of Proprietary
Biotreatment BMPs on the LID BMPs list in TGD, are manufactured to mimic natural
systems such as bio- retention areas by incorporating plants, soil, and microbes
engineered to provide treatment. They have been widely accepted by agencies and
installed in Southern California. The model we plan to use is a vault type unit with
internal by-pass for high flow.
In conclusion, there is one DMA area to be formed for the entire project area and we
chose to use a MWS device as LID BMPS to treat the entire DMA. Please refer to
Section IV.3.4 for further discussion as well as Section IV.8 for sizing calculations. The
design details are included in Appendix C.
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IV.1 Site Design and Drainage Characteristics
Table 1
Site Design BMPs
Technique Included?If no, state justification.Yes No
Minimize Directly Connected Impervious Areas (DCIAs)
(C-Factor Reduction)Yes
Create Reduced or “Zero Discharge” Areas
(Runoff Volume Reduction)1 No Very low infiltration rates on site
Minimize Impervious Area/Maximize Permeability
(C-Factor Reduction)2 Yes
Conserve Natural Areas
(C-Factor Reduction)No No natural area on site
1 Detention and retention areas incorporated into landscape design provide areas for retaining and detaining stormwater flows, resulting in
lower runoff rates and reductions in volume due to limited infiltration and evaporation. Such Site Design BMPs may reduce the size of
Treatment Control BMPs.
2 The “C Factor” is a representation of the ability of a surface to produce runoff. Surfaces that produce higher volumes of runoff are
represented by higher C Factors. By incorporating more pervious, lower C Factor surfaces into a development, lower volumes of runoff
will be produced. Lower volumes and rates of runoff translate directly to lowering treatment requirements.
DCIAs:
For the proposed drainage plan, the roof drains of proposed building structures
(including apartments and townhomes) will tie into the underground storm drain pipes
directly. The reason for this design is to avoid excessive surface water running in a tight
space near the building causing the safety and nuisance issues. Yet to achieve the
best C-Factor reduction, runoffs from other impervious areas will drain to the landscape
areas first where ever feasible prior to entering the storm drain system. Thus, in the
proposed drainage plan, the yard drains are to be constructed around the building
structure in the landscape areas to capture surface runoffs in order to achieve the best
C-Factor reduction for the site.
Minimize Impervious Areas:
The site layout was designed to minimize impervious areas where ever feasible.
Landscaping surrounds most of the buildings and the paving/hardscape has been
limited by creating as many pervious spaces as possible.
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IV.2 Source Control BMPs
IV.2.1 Routine Non-Structural BMPs
Table 2
Routine Non-Structural BMPs
BMP
No. Name
Check One If not applicable,
state brief reason.Included Not
Applicable
N1
Education for Property Owners, Tenants and
Occupants X
N2 Activity Restriction X
N3 Common Area Landscape Management X
N4 BMP Maintenance X
N5 Title 22 CCR Compliance X No Hazardous Materials
N6 Local Water Quality Permit Compliance X
This BMP is not applicable.
The City of Orange does
not issue water quality
permits.
N7 Spill Contingency Plan X No fuel storage
N8 Underground Storage Tank Compliance X
No underground storage
tank
N9 Hazardous Materials Disclosure Compliance X No Hazardous Materials
N10 Uniform Fire Code Implementation X No Hazardous Materials
N11 Common Area Litter Control X
N12 Employee Training X
N13 Housekeeping of Loading Docks X No proposed loading docks
N14 Common Area Catch Basin Inspection X No catch basin
N15 Street Sweeping Private Streets and Parking Lots X
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N1 Education for property owners, tenants and occupants
Practical information materials will be provided to the first residents/occupants/ tenants
on general housekeeping practices that contribute to the protection of stormwater
quality. The materials (included in this WQMP Appendix B) cover the following topics:
•The use of chemicals (including household type) that should be limited to the
property, with no discharge of specified wastes via hosing or other direct discharge
to gutters, catch basins, and storm drains.
• The proper handling of material such as fertilizers, pesticides, cleaning solutions,
pint products, automotive products, and swimming pool chemicals.
•The environmental and legal impacts of illegal dumping of harmful substances into
storm drains and sewers.
•Alternative household products which are safer to the environment.
•Household hazardous waste collection programs.
•Used oil recycling programs.
•Proper procedures for spill prevention and clean up.
•Proper storage of materials which pose pollution risks to local waters.
•Carpooling programs and public transportation alternatives to driving.
N2, Activity Restrictions
•No washing off of pavement. Nozzle sprayers can be used or pressure wash, but
not without containment of water for proper disposal.
•No car washing except in selected areas where designated (covered, clarified zone;
away from trash enclosure/storage).
•No maintenance or repair cars.
•No refueling.
•No washing off of paints into public right of way or on-site storm drains.
•No littering.
•No storage of material where it exposed to storm water.
N3, Common Area Landscape Management
Ongoing maintenance consistent with City Water Conservation Resolution, plus fertilizer
and/or pesticide usage consistent with City Guidelines for Use of Fertilizers and DAMP
Section 5.5. Maintenance includes mowing, weeding, and debris removal on a weekly
basis. Trimming, replanting and replacement of mulch shall be performed on an as-
needed basis. Trimmings, clippings, and other waste shall be properly disposed of on-
site in designated bins, i.e., or hauled off-site in accordance with local regulations.
In addition, the project will use smart irrigation systems in each landscape area to
control the timing and application of irrigation water, therefore to reduce excessive
irrigation runoff. Lastly, the project will choose plants with low irrigation requirements
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with native or drought tolerant species in compliance with local and state wide
ordinances.
N4, BMP Maintenance
The owner or property management firm will be responsible for the implementation and
maintenance of each applicable non-structural BMP, as well as scheduling inspections
and maintenance of all applicable structural BMP facilities through its staff, landscape
contractor, and/or any other necessary maintenance contractors. Details on BMP
Maintenance are provided in Section V of this report and Appendix D.
N11, Common Area Litter Control
Litter patrol, emptying of trash receptacles in common areas, and noting trash disposal
violations by tenants/homeowners and reporting the violations to the owner for
investigation. Outside bins must have solid lids to prevent storm water from entering.
N12, Employee Training
All employees and any contractors will require training to ensure that employees are
aware of maintenance activities that may result in pollutants reaching the storm drain.
Training will include, but not be limited to, spill cleanup procedures, proper waste
disposal, housekeeping practices, etc. Brochures are included in Appendix B.
N15, Street Sweeping Private Streets and Parking Lot
Parking lots and drive aisles must be mechanically swept (brush/vacuum sweeper)
monthly at minimum and more often as needed. Vacuum sweeping must occur just
prior to the rainy season as well. In addition, weekly broom sweep/blower sweep shall
occur as part of landscape maintenance, with visual inspection occurring on this routine
basis as well.
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IV.2.2 Routine Structural BMPs
Table 3
Routine Structural BMPs
Name
Check One If not applicable, state brief
reasonIncludedNot
Applicable
Provide storm drain system stenciling and
signage- “No Dumping – Drains to Ocean”X
Design and construct outdoor material storage
areas to reduce pollution introduction X No outdoor storage
Design and construct trash and waste storage
areas to reduce pollution introduction X
Use efficient irrigation systems & landscape
design X
Protect slopes and channels and provide energy
dissipation X 36” RCB at downstream
Incorporate requirements applicable to individual
project features
a. Dock areas X No dock
b. Maintenance bays X No Maintenance bay
c. Vehicle or community wash areas X No vehicle or community wash
d. Outdoor processing areas X No outdoor processing
e. Equipment wash areas X No equipment wash
f. Fueling areas X No fueling
g. Hillside landscaping X No hillside
h. Wash water control for food preparation
areas X No food preparation
Storm Drain Stenciling and Signage
All storm drain inlets and catch basins, constructed or modified, within the project area
will be stenciled or labeled. Signs which prohibit illegal dumping will be posted at public
access points along channels and creeks within the project area.
Design and Construct Trash and Waste Storage Areas to Reduce Pollution
Introduction
Trash areas will be paved, designed not to allow run-on, screened or walled to prevent
off-site transport of trash; and covered to minimize direct precipitation.
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Use Efficient Irrigation Systems & Landscape Design
Install smart irrigation controllers for common area landscaping including but not limited
to provisions for water sensors and programmable irrigation cycles. The irrigation
systems shall be in conformance with water use efficiency guidelines. Inspect
sprinklers on a regular basis and replace broken sprinklers immediately.
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IV.3 Low Impact Development BMP Selection
IV.3.1 Hydrologic Source Controls
Select from the following table all hydrologic source control BMPs that are used by the
project and identify in Site Plan. See Section 4.2 of Technical Guidance Document for
additional information.
Table 4
Hydrologic Source Control BMPs
Name Check If Used
Localized on-lot infiltration
Impervious area dispersion (e.g. roof top
disconnection)
Street trees (canopy interception)
Residential rain barrels (not actively managed)
Green roofs/Brown roofs
Blue roofs
Other:
Other:
Other:
Other:
Other:
Other:
Other:
Other:
The project will not pursue HSCs due to that all required project’s design capture
volume will be mitigated by biotreatment BMPs.
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IV.3.2 Infiltration BMPs
Table 5
Infiltration BMPs
Name Check If
Used
Bioretention without underdrains
Rain gardens
Porous landscaping
Infiltration planters
Retention swales
Infiltration trenches
Infiltration basins
Drywells
Subsurface infiltration galleries
French drains
Permeable asphalt
Permeable concrete
Permeable concrete pavers
Other:
Other:
Infiltration is not presumed to be feasible for the project site due to the low infiltration
rate of Soil Type “D” and geotechnical hazard. Please see attached “Infiltration BMP
Feasibility Worksheet”. For more details p lease see our discussion in Section IV.1.
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IV.3.3 Evapotranspiration, Rainwater Harvesting BMPs
Table 6
Evapotranspiration, Rainwater Harvesting BMP
Name Check If Used
All HSCs; See Section IV.3.1
Surface-based infiltration BMPs
Biotreatment BMPs
Above-ground cisterns and basins
Underground detention
Other:
Other:
Other:
The project will not pursue evapotranspiration, rainwater harvesting BMPs due to limited
irrigation demand (See attached Worksheet J).
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IV.3.4 Biotreatment BMPs
Describe any biotreatment BMPs used in the project and include separate sections for
selection, suitability, sizing, and infeasibility, as applicable. See Section 4.6 of the
Technical Guidance Document for additional information.
Table 7
Biotreatment BMPs
Bioretention with underdrains
Storm water planter boxes with underdrains
Rain gardens with underdrains
Constructed wetlands
Vegetated swales
Vegetated filter strips
Proprietary vegetated biotreatment systems X
Wet extended detention basin
Dry extended detention basins
Other:
Other:
The project will pursue biotreatment BMPs in the project area. The selected BMPs
device is the “Modular Wetland System” (MWS), which is a type of Proprietary
Biotreatment BMPs on Table 7. For more details in BMPs selection please see our
discussion in Section IV.1.
The MWS has been widely accepted by agencies and installed in Southern California.
MWS devices are manufactured to mimic natural systems such as bio- retention areas
by incorporating plants, soil, and microbes engineered to provide treatment. Its
pollutants removal efficiency per manufacturer's data is summarized in the table below:
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Pollutant Parameter Performance
Suspended-solids (sediment turbidity)H
Nutrients (phosphorus)M
Nutrients (nitrogen compounds)M
Heavy metals M
Pathogens (bacteria/virus)M
Oil and grease H
Dissolved toxic organic compounds H
Trash and debris H
Notes:
H= high (> 70%); M = medium (40-70%); L = low (<40%)
As shown in the above table, the MWS can remove the primary pollutants of concern
with at least M or H level of effectiveness from the project.
In design support, please refer to Section IV.8 for sizing calculations. The MWS design
details and maintenance information are included in Appendices C and D respectively.
IV.3.5 Hydromodification Control BMPs
Describe any hydromodification control BMPs used in project. Refer to Section 5 of the
Technical Guidance Document for additional information. Include sections for selection,
suitability, sizing, and infeasibility, as applicable. Detail compliance with Conditions of
Approval (if applicable).
N/A
IV.3.6 Regional/Sub-Regional LID BMPs
Describe regional/sub-regional LID BMPs in which the project will participate. Refer to
Section 7.II-2.4.3.2 of the Model WQMP for assistance in completing section .
N/A
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IV.3.7 Treatment Control BMPs
Describe any Treatment control BMPs used in project. Treatment control BMPs can
only be considered if the project conformance analysis indicates that it is not feasible to
retain the full design capture volume with LID BMPs. Include sections for selection,
sizing, and infeasibility, as applicable.
N/A
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IV.4 Water Quality Credits
Describe any water quality credits applicable to project (credits can only be taken if
proposed LID BMPs cannot capture entire Design Storm Volume). Refer to Section 7.II-
3.1 of the Model WQMP.
N/A
IV.5 Alternative Compliance Plan
Describe the alternative compliance plan (if applicable). Include alternative compliance
obligations (i.e., gallons, pounds) and describe proposed alternative compliance
measures. Refer to Section 7.II 3.0 in the Model WQMP.
N/A
IV.6 Vector Control
In general no standing water will exist in the proposed MWS unit. The Project will
implement a self-inspection checklist following Manufacturer's recommendation to
address any potential vector control issue. For details please see Section V and
Appendix D.
IV.7 Drainage Management Area (DMA)
Describe each DMA used in project, the BMPs in each DMA and the area treated.
DMA Number BMPs Area Treated
#1 Modular Wetland System
(MWS)
2.667 (ac)
Total Area 2.667 (ac)
Total Project Area = 2.667 (ac)
Prepared on 03/30/2020; Revised on (N/A)24
Preliminary WQMP for
Orange Corp Yard Workforce Housing
IV.8 Calculations
(a) Design Capture Volume (DCV)
Prepared on 03/30/2020; Revised on (N/A)25
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(b) BMPs Sizing
Prepared on 03/30/2020; Revised on (N/A)26
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(c) Design Rainfall Intensity for Flow-based BMPs
Prepared on 03/30/2020; Revised on (N/A)27
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V Implementation, Maintenance and Inspection Responsibility for
BMPs (O&M Plan)
Responsible Party Information (Local Contact Information)
Name: Todd Cottle Title: Owner
Company:C & C Development Co., LLC Phone Number: (714) 288-7600
Complete frequency matrix. Expand or increase each cell box to provide the
information required.
Table 8 - Frequency Inspection Matrix
BMP Responsible Party Maintenance Activity Inspection/Maintenance
Frequency
Source Control BMPs (Structural and Non-structural)
N1, Education for Property
Owners, Tenants and
Occupants
C & C Development
Co., LLC
Owner / Property Management Co. shall
provide education materials to the first
residents/occupants/tenants; thereafter
such materials shall be periodically
provided to all of its members.
Upon lease agreement,
Annually thereafter
N2, Activity Restriction C & C Development
Co., LLC
Owner / Property Management Co. shall
prescribe activity restrictions described in
this report through lease terms or other
equally effective measure for the
property. Restrictions include prohibiting
washing off of pavement, vehicle
washing, vehicle maintenance, refueling,
washing off of paints, littering, outdoor
storage of material, etc.
Daily
N3, Common Area Landscape
Management
C & C Development
Co., LLC
Maintenance shall be consistent with City
requirements, plus fertilizer and/or
pesticide usage shall be consistent with
City guidelines for use of fertilizers and
pesticides (OC DAMP Section 5.5).
Maintenance includes mowing, weeding,
and debris removal on a weekly basis.
Trimming, replanting and replacement of
mulch shall be performed on an as-
needed basis. Trimmings, clippings, and
other waste shall be properly disposed of
off-site in accordance with local
regulations.
Monthly
Prepared on 03/30/2020; Revised on (N/A)28
Preliminary WQMP for
Orange Corp Yard Workforce Housing
BMP Responsible Party Maintenance Activity Inspection/Maintenance
Frequency
Materials temporarily stockpiled during
maintenance activities shall be placed
away from water courses and drain
inlets.
N11, Common Area Litter
Control
C & C Development
Co., LLC
Litter patrol, violations investigation,
reporting and other litter control activities
shall be performed in conjunction with
maintenance activities. Litter collection
and removal shall be performed on a
weekly basis.
Weekly
N12, Employee Training C & C Development
Co., LLC
The owners shall educate all new
employees/managers on storm water
pollution prevention, particularly good
housekeeping practices, prior to the start
of the rainy season (October 1).
Refresher courses shall be conducted
annually. Materials that may be used are
attached to this WQMP.
Annually
N15, Street Sweeping Private
Streets and Parking Lots
C & C Development
Co., LLC
Parking lots and drive aisles must be
mechanically swept (brush/vacuum
sweeper) monthly at minimum and more
often as needed. Vacuum sweeping
must occur just prior to the rainy season
as well. In addition, weekly broom
sweep/blower sweep shall occur as part
of landscape maintenance, with visual
inspection occurring on this routine basis
as well.
Monthly
Storm Drain Stenciling and
Signage
C & C Development
Co., LLC
At minimum, once a year inspect for
restenciling needs; restencil when not
legible/damaged.
Annually
Design and construct trash and
waste SD-32 storage areas to
reduce pollution introduction
C & C Development
Co., LLC
Trash areas will be paved, designed not
to allow run-on, screened or walled to
prevent off-site transport of trash; and
covered to minimize direct precipitation.
Sweep trash area at least once per week
and before October 1st each year. Keep
area clean of trash & debris at all times.
Maintain trash receptacles in accordance
with BMP N11.
Annually
Use efficient irrigation systems
& landscape design
C & C Development
Co., LLC
In conjunction with routine maintenance
activities, verify that landscape design
continues to function properly by
adjusting properly to eliminate overspray
to hardscape areas, and to verify that
irrigation timing and cycle lengths are
adjusted in accordance with water
demands, given time of year, weather,
day or nighttime temperatures based on
system specifications and local climate
Monthly
Prepared on 03/30/2020; Revised on (N/A)29
Preliminary WQMP for
Orange Corp Yard Workforce Housing
BMP Responsible Party Maintenance Activity Inspection/Maintenance
Frequency
patterns.
Low Impact Development and Treatment BMPs
Modular Wetland System (BMP
#1) (See “Manufacturer
Maintenance Manual” in
Appendix D)
C & C Development
Co., LLC
Trash from screening device and
sediment from separation chamber will
be removed after major storms as
necessary but at minimum once a year
before winter season. Cartridge filter and
drain down filter medias will be replaced
once a year, during dry season and after
any chemical spill. Vegetation will be
trimmed once every 6-months. See other
maintenance activities in Appendix D.
Annually, Semi-annually, Monthly &
After Major Storms
Regulatory Permits
N/A
Funding
Long-term funding for BMP maintenance will be provided by the owner and/or Property
Management Company.
Prepared on 03/30/2020; Revised on (N/A)30
Preliminary WQMP for
Orange Corp Yard Workforce Housing
OWNER SELF CERTIFICATION STATEMENT
As the owner representative of the Orange Corp Yard Workforce Housing for which a
Water Quality Management Plan (WQMP) was approved by the City, I hereby certify
under penalty of law that all Best Management Practices contained within the approved
Project WQMP have been maintained and inspected in accordance with the schedule
and frequency outlined in the approved WQMP Maintenance Table.
The maintenance activities and inspections conducted are shown in the attached table
and have been performed by qualified and knowledgeable individuals. Structural
Treatment BMPs have been inspected and certified by a licensed professional engineer.
To the best of my knowledge, the information submitted is true and accurate and
complete. I am aware that there are significant penalties for submitting false
information, including the possibility of fines and citations for violating water quality
regulations.
Signed: ____________________________________
Name: ____________________________________
Title: ____________________________________
Company: __________________________________
Address: __________________________________
Telephone Number: ___________________________
Date: _________________
Prepared on 03/30/2020; Revised on (N/A)31
Preliminary WQMP for
Orange Corp Yard Workforce Housing
BMP Implementation Tracking Table
BMP Activity Completion Dates or
Frequency
Initial
Source Control BMPs (Structural and Nonstructural)
N1, Education for Property
Owners, Tenants and
Occupants
Continuous education
N2, Activity Restriction Continuous activity restriction
N3, Common Area
Landscape Management
Maintenance shall be consistent with City
requirements, plus fertilizer and/or pesticide usage
shall be consistent with County guidelines for use of
fertilizers and pesticides (OC DAMP Section 5.5).
Maintenance includes mowing, weeding, and debris
removal on a weekly basis. Trimming, replanting and
replacement of mulch shall be performed on an as-
needed basis. Trimmings, clippings, and other waste
shall be properly disposed of off-site in accordance
with local regulations. Materials temporarily
stockpiled during maintenance activities shall be
placed away from water courses and drain inlets.
N4, BMP Maintenance Maintenance of BMPs implemented at the project
site shall be performed at the frequency prescribed
in this WQMP. Records of inspections and BMP
maintenance shall be maintained by the Owner and
documented with the WQMP, and shall be available
for review upon request.
N11, Common Area Litter
Control
Litter patrol, violations investigation, reporting and
other litter control activities shall be performed in
conjunction with maintenance activities. Litter
collection and removal shall be performed on a
weekly basis.
N12, Employee Training The responsible party shall educate all new
employees/managers on storm water pollution
prevention, particularly good housekeeping
practices, prior to the start of the rainy season
(October 1). Refresher courses shall be conducted
on an as needed basis. Materials that may be used
are attached to this WQMP.
N15, Street Sweeping
Private Streets and Parking
Lots
Parking lots and drive aisles must be swept at least
monthly, including prior to the start of the rainy
season (October 1st).
Storm Drain Stenciling and
Signage
At minimum, once a year inspect for restenciling
needs; restencil when not legible/damaged.
Design and construct trash
and waste SD-32 storage
areas to reduce pollution
introduction
Trash areas will be paved, designed not to allow
run-on, screened or walled to prevent off-site
transport of trash; and covered to minimize direct
precipitation.
Sweep trash area at least once per week and before
October 1st each year. Keep area clean of trash &
Prepared on 03/30/2020; Revised on (N/A)32
Preliminary WQMP for
Orange Corp Yard Workforce Housing
debris at all times. Maintain trash receptacles in
accordance with BMP N11.
Use efficient irrigation
systems & landscape
design
In conjunction with routine maintenance activities,
verify that landscape design continues to function
properly by adjusting properly to eliminate overspray
to hardscape areas, and to verify that irrigation
timing and cycle lengths are adjusted in accordance
with water demands, given time of year, weather,
day or nighttime temperatures based on system
specifications and local climate patterns.
Low Impact Development and Treatment BMPs
Vegetated Swale Regrade swale bottom and reseed to mitigate
ponding of water between storms or excessive
erosion and scouring. Install or replace low flow
channel using pea gravel media to better convey
nuisance flows. Revegetate bare exposed portions
of the swale to restore vegetation to original level of
coverage. De-thatch grass to remove accumulated
sediment and aerate compacted areas to promote
infiltration. Complete maintenance guidelines please
refer to Appendix D.
* This sheet is to be submitted annually with the Owner Self Certification Statement.
** Structural Treatment BMPs should be certified by a Licensed Professional Engineer.
Prepared on 03/30/2020; Revised on (N/A)33
Preliminary WQMP for
Orange Corp Yard Workforce Housing
VI Location Map, Site Plan, and BMP Details
Include a location map that identifies project location and proximity to nearby water
bodies. In an 11X17 sheet Identify land use, cover, feasibility constraints, structures,
buildings, number of units, landscape areas, storm drain inlets, storm drain facilities,
drainage flow direction, structural and treatment BMP locations, dumpsters, trash
enclosures, wash areas, etc.
Delineate drainage management areas showing limits (acreage) of each drainage area
for all structural, treatment and Low Impact Development BMPs used and provide BMP
details on plan or in Appendix C.
Prepared on 03/30/2020; Revised on (N/A)34
Preliminary WQMP for
Orange Corp Yard Workforce Housing
Prepared on 03/30/2020; Revised on (N/A)35
Preliminary WQMP for
Orange Corp Yard Workforce Housing
SITE MAP (W/ PROPOSED LOT LINES)
Prepared on 03/30/2020; Revised on (N/A)36
MWS
T1
Storm Drain Stencile
Storm Drain Stencile
Storm Drain Stencile
Storm Drain Stencile
Storm Drain Stencile
36" RCPOutlet
W. Struck Ave.W. Struck Ave.AT&SF RR
AT&SF RR
Preliminary BMP Site Plan
Date: 03/30/2020
Sheet 1 of 1
Orange Corp Yard Workforce Housing Orange, CA
Notes:
1) Onsite Soil Type = D
2) Roof drain downspouts will tie into SD system
(to avoid excessive surface water ponding).
LEGEND
DMA Drainage Boundary
Pervious Landscaped Area
!Storm Drain Stencile
UV1 BMP ID
BMP Structure
Treatment/Hydromodification BMPs List:
UV1 Proprietary Biotreatment -
Bio Clean Modular Wetland System
0 2010
Feet
Preliminary WQMP for
Orange Corp Yard Workforce Housing
VII Educational Materials
Education Materials
Residential Material
(http://www.ocwatersheds.com)
Check If
Applicable
Business Material
(http://www.ocwatersheds.com)
Check If
Applicable
The Ocean Begins at Your Front Door Tips for the Automotive Industry
Tips for Car Wash Fund-raisers Tips for Using Concrete and Mortar
Tips for the Home Mechanic Tips for the Food Service Industry
Homeowners Guide for Sustainable
Water Use
Proper Maintenance Practices for Your
Business
Household Tips
Other Material Check If
AttachedProper Disposal of Household
Hazardous Waste
Recycle at Your Local Used Oil
Collection Center (North County)Watershed Brochure
Recycle at Your Local Used Oil
Collection Center (Central County)Children's Brochure
Recycle at Your Local Used Oil
Collection Center (South County)
Tips for Maintaining a Septic Tank
System
Responsible Pest Control
Sewer Spill Response
Tips for the Home Improvement
Projects
Tips for Horse Care
Tips for Landscaping and Gardening
Tips for Pet Care
Tips for Pool Maintenance
Tips for Residential Pool, Landscape
and Hardscape Drains
Tips for Projects Using Paint
Prepared on 03/30/2020; Revised on (N/A)37
Preliminary WQMP for
Orange Corp Yard Workforce Housing
Appendix A:
Conditions of Approval
City Council Resolution ______ dated _________
(to-be-provided)
Prepared on 03/30/2020; Revised on (N/A)38
Appendix B:
Educational Material
(to-be-provided)
Appendix C:
BMP Details
STANDARD DETAIL
STORM WATER BIOFILTRATION SYSTEM
MWS-L-8-16-6'-0"-V-UG
GENERAL NOTES
INSTALLATION NOTES
SITE SPECIFIC DATA
INTERNAL BYPASS DISCLOSURE:
PLAN VIEW
ELEVATION VIEW RIGHT END VIEW
LEFT END VIEW
Appendix D:
BMP Maintenance Information
www.modularwetlands.com
Maintenance Guidelines for
Modular Wetland System - Linear
Maintenance Summary
o Remove Trash from Screening Device – average maintenance interval is 6 to 12 months.
(5 minute average service time).
o Remove Sediment from Separation Chamber – average maintenance interval is 12 to 24 months.
(10 minute average service time).
o Replace Cartridge Filter Media – average maintenance interval 12 to 24 months.
(10-15 minute per cartridge average service time).
o Replace Drain Down Filter Media – average maintenance interval is 12 to 24 months.
(5 minute average service time).
o Trim Vegetation – average maintenance interval is 6 to 12 months.
(Service time varies).
System Diagram
Access to screening device, separation
chamber and cartridge filter
Access to drain
down filter
Pre-Treatment
Chamber
Biofiltration Chamber
Discharge
Chamber
Outflow
Pipe
Inflow Pipe
(optional)
www.modularwetlands.com
Maintenance Procedures
Screening Device
1. Remove grate or manhole cover to gain access to the screening device in the Pre-
Treatment Chamber. Vault type units do not have screening device. Maintenance
can be performed without entry.
2. Remove all pollutants collected by the screening device. Removal can be done
manually or with the use of a vacuum truck. The hose of the vacuum truck will not
damage the screening device.
3. Screening device can easily be removed from the Pre-Treatment Chamber to gain
access to separation chamber and media filters below. Replace grate or manhole
cover when completed.
Separation Chamber
1. Perform maintenance procedures of screening device listed above before
maintaining the separation chamber.
2. With a pressure washer spray down pollutants accumulated on walls and cartridge
filters.
3. Vacuum out Separation Chamber and remove all accumulated pollutants. Replace
screening device, grate or manhole cover when completed.
Cartridge Filters
1. Perform maintenance procedures on screening device and separation chamber
before maintaining cartridge filters.
2. Enter separation chamber.
3. Unscrew the two bolts holding the lid on each cartridge filter and remove lid.
4. Remove each of 4 to 8 media cages holding the media in place.
5. Spray down the cartridge filter to remove any accumulated pollutants.
6. Vacuum out old media and accumulated pollutants.
7. Reinstall media cages and fill with new media from manufacturer or outside
supplier. Manufacturer will provide specification of media and sources to purchase.
8. Replace the lid and tighten down bolts. Replace screening device, grate or
manhole cover when completed.
Drain Down Filter
1. Remove hatch or manhole cover over discharge chamber and enter chamber.
2. Unlock and lift drain down filter housing and remove old media block. Replace with
new media block. Lower drain down filter housing and lock into place.
3. Exit chamber and replace hatch or manhole cover.
www.modularwetlands.com
Maintenance Notes
1. Following maintenance and/or inspection, it is recommended the maintenance
operator prepare a maintenance/inspection record. The record should include any
maintenance activities performed, amount and description of debris collected, and
condition of the system and its various filter mechanisms.
2. The owner should keep maintenance/inspection record(s) for a minimum of five
years from the date of maintenance. These records should be made available to
the governing municipality for inspection upon request at any time.
3. Transport all debris, trash, organics and sediments to approved facility for disposal
in accordance with local and state requirements.
4. Entry into chambers may require confined space training based on state and local
regulations.
5. No fertilizer shall be used in the Biofiltration Chamber.
6. Irrigation should be provided as recommended by manufacturer and/or landscape
architect. Amount of irrigation required is dependent on plant species. Some plants
may require irrigation.
www.modularwetlands.com
Maintenance Procedure Illustration
Screening Device
The screening device is located directly
under the manhole or grate over the
Pre-Treatment Chamber. It’s mounted
directly underneath for easy access
and cleaning. Device can be cleaned by
hand or with a vacuum truck.
Separation Chamber
The separation chamber is located
directly beneath the screening device.
It can be quickly cleaned using a
vacuum truck or by hand. A pressure
washer is useful to assist in the
cleaning process.
www.modularwetlands.com
Cartridge Filters
The cartridge filters are located in the
Pre-Treatment chamber connected to
the wall adjacent to the biofiltration
chamber. The cartridges have
removable tops to access the
individual media filters. Once the
cartridge is open media can be
easily removed and replaced by hand
or a vacuum truck.
Drain Down Filter
The drain down filter is located in the
Discharge Chamber. The drain filter
unlocks from the wall mount and hinges
up. Remove filter block and replace with
new block.
www.modularwetlands.com
Trim Vegetation
Vegetation should be maintained in the
same manner as surrounding vegetation
and trimmed as needed. No fertilizer shall
be used on the plants. Irrigation
per the recommendation of the
manufacturer and or landscape
architect. Different types of vegetation
requires different amounts of
irrigation.
www.modularwetlands.com
Inspection Form
Modular Wetland System, Inc.
P. 760.433-7640
F. 760-433-3176
E. Info@modularwetlands.com
For Office Use Only
(city) (Zip Code)(Reviewed By)
Owner / Management Company
(Date)
Contact Phone ( )_
Inspector Name Date / / Time AM / PM
Weather Condition Additional Notes
Yes
Depth:
Yes No
Modular Wetland System Type (Curb, Grate or UG Vault):Size (22', 14' or etc.):
Other Inspection Items:
Storm Event in Last 72-hours? No Yes Type of Inspection Routine Follow Up Complaint Storm
Office personnel to complete section to
the left.
2972 San Luis Rey Road, Oceanside, CA 92058 P (760) 433-7640 F (760) 433-3176
Inspection Report
Modular Wetlands System
Is the filter insert (if applicable) at capacity and/or is there an accumulation of debris/trash on the shelf system?
Does the cartridge filter media need replacement in pre-treatment chamber and/or discharge chamber?
Any signs of improper functioning in the discharge chamber? Note issues in comments section.
Chamber:
Is the inlet/outlet pipe or drain down pipe damaged or otherwise not functioning properly?
Structural Integrity:
Working Condition:
Is there evidence of illicit discharge or excessive oil, grease, or other automobile fluids entering and clogging the
unit?
Is there standing water in inappropriate areas after a dry period?
Damage to pre-treatment access cover (manhole cover/grate) or cannot be opened using normal lifting
pressure?
Damage to discharge chamber access cover (manhole cover/grate) or cannot be opened using normal lifting
pressure?
Does the MWS unit show signs of structural deterioration (cracks in the wall, damage to frame)?
Project Name
Project Address
Inspection Checklist
CommentsNo
Does the depth of sediment/trash/debris suggest a blockage of the inflow pipe, bypass or cartridge filter? If yes,
specify which one in the comments section. Note depth of accumulation in in pre-treatment chamber.
Is there a septic or foul odor coming from inside the system?
Is there an accumulation of sediment/trash/debris in the wetland media (if applicable)?
Is it evident that the plants are alive and healthy (if applicable)? Please note Plant Information below.
Sediment / Silt / Clay
Trash / Bags / Bottles
Green Waste / Leaves / Foliage
Waste:Plant Information
No Cleaning Needed
Recommended Maintenance
Additional Notes:
Damage to Plants
Plant Replacement
Plant Trimming
Schedule Maintenance as Planned
Needs Immediate Maintenance
www.modularwetlands.com
Maintenance Report
Modular Wetland System, Inc.
P. 760.433-7640
F. 760-433-3176
E. Info@modularwetlands.com
For Office Use Only
(city) (Zip Code)(Reviewed By)
Owner / Management Company
(Date)
Contact Phone ( )_
Inspector Name Date / / Time AM / PM
Weather Condition Additional Notes
Site
Map #
Comments:
2972 San Luis Rey Road, Oceanside, CA 92058 P. 760.433.7640 F. 760.433.3176
Inlet and Outlet
Pipe Condition
Drain Down Pipe
Condition
Discharge Chamber
Condition
Drain Down Media
Condition
Plant Condition
Media Filter
Condition
Long:
MWS
Sedimentation
Basin
Total Debris
Accumulation
Condition of Media
25/50/75/100
(will be changed
@ 75%)
Operational Per
Manufactures'
Specifications
(If not, why?)
Lat:MWS
Catch Basins
GPS Coordinates
of Insert
Manufacturer /
Description / Sizing
Trash
Accumulation
Foliage
Accumulation
Sediment
Accumulation
Type of Inspection Routine Follow Up Complaint Storm Storm Event in Last 72-hours? No Yes
Office personnel to complete section to
the left.
Project Address
Project Name
Cleaning and Maintenance Report
Modular Wetlands System
Appendix E:
Geotechnical Report
PRELIMINARY GEOTECHNICAL INVESTIGATION
PROPOSED RESIDENTIAL DEVELOPMENT
EASTERN 2.54 ACRES OF APN 375-291-14
ORANGE, CALIFORNIA
PROJECT NO. 33616.1
FEBRUARY 25, 2020
Prepared For:
C & C Development
14211 Yorba Street, Suite 200
Tustin, California 92780
Attention: Mr. Scott Bering
February 25, 2020
C & C Development Project No. 33616.1
14211 Yorba Street, Suite 200
Tustin, California 92780
Attention: Mr. Scott Bering
Subject: Preliminary Geotechnical Investigation, Proposed Residential Development,
Eastern 2.54 Acres of APN 375-291-14, Orange, California.
LOR Geotechnical Group, Inc., is pleased to present this report summarizing our
geotechnical investigation for the above referenced project. In summary, it is our opinion
that the proposed development is feasible from a geotechnical perspective, provided the
recommendations presented in the attached report are incorporated into design and
construction.
To provide adequate support for the proposed residential structures, we recommend that
a compacted fill mat be constructed beneath footings and slabs. The compacted fill mat
will provide a dense, high-strength soil layer to uniformly distribute the anticipated
foundation loads over the underlying soils. All undocumented fill material and any loose
alluvial materials should be removed from structural areas and areas to receive engineered
compacted fill. The data developed during this investigation indicates that removals on the
order of approximately 5 feet will be required within the currently planned development
areas. The given removal depths are preliminary. The actual depths of the removals should
be determined during the grading operation by observation and/or in-place density testing.
Medium expansive soils and poor R-value quality soils were encountered on the site. A
negligible sulfate content was found for the soils tested. Near completion and/or at the
completion of site grading, additional foundation and subgrade soils should be tested to
verify their expansion potential, soluble sulf ate content, and R-value quality.
LOR Geotechnical Group, Inc.
Table of Contents Page No.
INTRODUCTION......................................................1
PROJECT CONSIDERATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
EXISTING SITE CONDITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
AERIAL PHOTOGRAPH ANALYSIS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
FIELD EXPLORATION PROGRAM.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
LABORATORY TESTING PROGRAM.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
GEOLOGIC CONDITIONS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Regional Geologic Setting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Site Geologic Conditions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Fill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Older Alluvium.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Groundwater Hydrology.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Surface Runoff.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Mass Movement.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Faulting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Historical Seismicity.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Secondary Seismic Hazards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Liquefaction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Seiches/Tsunamis.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Flooding (Water Storage Facility Failure). . . . . . . . . . . . . . . . . . . . . . . . . 9
Seismically-Induced Landsliding.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Rockfalls. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Seismically-Induced Settlement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
SOILS AND SEISMIC DESIGN CRITERIA (California Building Code 2019). . . . . . 10
Site Classification.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
CBC Earthquake Design Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
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CONCLUSIONS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
General. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Foundation Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Soil Expansiveness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Sulfate Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Geologic Mitigations.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Seismicity.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
RECOMMENDATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Geologic Recommendations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
General Site Grading.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Initial Site Preparation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Preparation of Fill Areas. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Preparation of Foundation Areas.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Engineered Compacted Fill. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Short-Term Excavations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Slope Construction.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Slope Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Foundation Design.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Settlement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Building Area Slab-On-Grade. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Exterior Flatwork. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Wall Pressures.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Sulfate Protection. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Preliminary Pavement Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
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LIMITATIONS.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
TIME LIMITATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
CLOSURE...........................................................25
REFERENCES........................................................26
APPENDICES
Appendix A
Index Map.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-1
Architectural Site Plan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-2
Regional Geologic Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-3
Historical Seismicity Maps. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A-4 and A-5
Appendix B
Field Investigation Program. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B
Boring Logs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-1 through B-6
Boring Log Legend. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-L
Soil Classification Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B-ii
Appendix C
Laboratory Testing Program.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C
Gradation Curves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-1
Atterberg Limits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . C-2
Appendix D
Seismic Design Spectra. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . D
LOR GEOTECHNICAL GROUP, INC.
C & C Development Project No. 33616.1
February 25, 2020
INTRODUCTION
During February of 2020, a Preliminary Geotechnical Investigation was performed by LOR
Geotechnical Group, Inc., for proposed residential development of the eastern 2.54 acres
of APN 375-291-14 in the City of Orange, California. The purpose of this investigation was
to conduct a technical evaluation of the geologic setting of the site and to provide
geotechnical design recommendations for the proposed improvements. The scope of our
services included:
•Review of available pertinent geotechnical literature, reports, maps, and agency
information pertinent to the study area;
•Interpretation of aerial photographs of the site and surrounding regions dated 1946
through 2018;
•Geologic field reconnaissance mapping to verify the areal distribution of earth units
and significance of surficial features as compiled from documents, literature, and
reports reviewed;
•A subsurface field investigation to determ ine the physical soil conditions pertinent
to the proposed dev elopment;
•Laboratory testing of selected soil samples obtained during the field investigation;
•Development of geotechnical recommendations for site grading and foundation
design; and
•Preparation of this report summarizing our findings, and providing conclusions and
recommendations for site development.
The approximate location of the site is shown on the attached Index Map, Enclosure A-1,
within Appendix A.
To orient our investigation at the site, you provided us with an Architectural Site Plan,
prepared by IDE Arc Architecture & Planning, dated September 12, 2019, that showed the
proposed development. As noted on that map, the site will be developed with a total of 62
apartment units within two, three-story structures and the associated improvements. The
Architectural Site Plan was utilized as a base map for our field investigation and is
presented as Enclosure A-2, w ithin Appendix A.
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PROJECT CONSIDERATIONS
The proposed two structures will be three stories in height and are anticipated to be of
wood frame construction with an exterior plaster veneer. Light to moderate foundation
loads are anticipated with such structures. Cuts and fills on the order of a few feet are
anticipated to create the planar building pads.
EXISTING SITE CONDITIONS
The subject site is vacant land, comprising approximately 2.5 acres of an irregular-shaped
portion of a larger 17.23-acre parcel of land which comprises the City of Orange Corporate
Yard and Police Department building, located at the northeast corner of the intersection
at North Batavia Street and W est Struck Avenue. The subject site is situated in the far east
end of the 17.23-acre parcel. The subject site is largely absent of vegetation, with the
exception of dense bushes and trees along the north bound ary and landscaping
improvements consisting of pine trees, ornamental plants, and grass near and/or within the
south side of the subject site along the north side of W est Struck Avenue. The ground
surface of most of the subject site is dirt covered in gravel and/or asphalt grindings and
asphalt, with some bare dirt present. The site is relatively planar with a very gentle fall
towards the south-southwest to W . Struck Avenue. A concrete v-ditch traverses the eastern
site boundary from offsite to the northwest.
Numerous items, trucks, tractors, trailers, plant trimmings, light standards, k-rails, and other
items associated with the site’s current use as a city yard.
The site is bound on the north by commercial buildings, on the east by two sets of railroad
tracks with multi-family residential beyond, on the south by W . Struck Avenue, a fully
improved roadway, followed by commercial buildings, and on the west by the remainder
of the city yard for various departm ents.
AERIAL PHOTOGRAPH ANALYSIS
The aerial photographs reviewed consisted of vertical aerial stereoscopic photographs of
varying scales. W e reviewed imagery available from Google Earth (2020) and from Historic
Aerials (2020).
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The site consisted of groves with surrounding properties from 1946, the earliest photograph
available, to 1963 when the groves were removed. The site remained vacant until the 1980
photograph when it was a part of the city yard to present day. The southern approximately
half of the site contained asphalt concrete paving in 2002. Photographs from 1980 to 2018
showed the site was used f or storage, similar to that seen today.
Our review of the aerial photographs did not reveal any adverse geologic conditions, such
as possible f aults or landslides, as being present at or within close proximity to the site.
FIELD EXPLORATION PROGRAM
Our subsurface field exploration program was conducted on February 4, 2020 and
consisted of drilling 6 exploratory borings with a truck-mounted Mobile B-61 drill rig
equipped with 8-inch diameter hollow stem augers. The borings were drilled to depths of
approximately 15 to a refusal depth of 41 feet below the existing ground surface. The
approximate locations of our exploratory borings are presented on the attached
Architectural Site Plan, Enclosure A-2 w ithin Appendix A.
The subsurface conditions encountered in the exploratory borings were logged by a
geologist from this firm. Relatively undisturbed and bulk samples were obtained at a
maximum depth interval of 5 feet and returned to our geotechnical laboratory in sealed
containers for further testing and evaluation. A detailed description of the field exploration
program and the boring logs are presented in Appendix B.
LABORATORY TESTING PROGRAM
Selected soil samples obtained during the field investigation were subjected to laboratory
testing to evaluate their physical and engineering properties. Laboratory testing included
in-place moisture content and dry density, laboratory compaction characteristics, direct
shear, sieve analysis, sand equivalent, R-value, expansion index, Atterberg limits, and
soluble sulfate content. A detailed description of the laboratory testing program and the test
results are presented in Appendix C.
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GEOLOGIC CONDITIONS
Regional Geologic Setting
The subject site is located within northeastern Orange County between the Santa Ana
River to the west and the Peralta Hills to the east. These small hills form a series of low
hills that extend as a northwest trending flank of the larger Santa Ana Mountains to the
east and southeast. The Santa Ana Mountains are in turn one of the several mountain
ranges that form the interior portion of southern California known as the Peninsular Ranges
geomorphic province. This province consists of a series of northwest trending mountains
that extend from the Los Angeles Basin south, to the Mexican border and beyond. The
Santa Ana Mountains themselves form the eastern boundary of Orange County and
contain some of the oldest rocks within the County, the Triassic to Jurassic aged
metasedimentary rocks of the Bedford Canyon formation that formed around 225 million
years ago. Underlying the Bedf ord Canyon formation are units of relatively younger
igneous rocks of Cretaceous age that form the core of the mountains from intrusion of
magma into this area around 65 million years ago. Especially along the western flanks of
the Santa Ana mountains, these older metamorphic and igneous rocks are overlain by
younger rocks of sedimentary and volcanic origin that documents the fluctuating history of
this region from shallow continental sea to near shore continental environments, with
periodic volcanic eruptions.
Erosion of the Santa Ana Mountains to the east and southeast, as well as the hills to the
east, by the Santa Ana Rivera and its tributaries, such as the Santiago Creek to the
east-southeast, has deposited a relatively thick sequence of relatively unconsolidated
alluvium of varies ages and levels in a series of terraces along this broad valley. In their
regional geologic map of the area, the USGS indicated that the site is situated upon older
alluvial materials (Morton and Miller, 2006). This unit was described as composed of
indurated, reddish brown, silty sand alluvial fan deposits. This deposit is considered to
have been deposited in the late to middle Pleistocene age, or on the order of about 11,000
years or slightly older. This older unit has been slightly incised, and replaced with similar,
unconsolidated, m aterials along the active creek beds.
The region, like much of southern California, has numerous faults. These are all associated
with the San Andreas fault zone, located approximately 63 kilometers (39 miles) to the
northeast, that results from the area's location and history as a major plate boundary with
various types of relative motion. Many of these faults have been inactive for millions of
years and are noted only by abrupt changes of rock types. Other faults show evidence that
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they have been active in geologically recent times, since the Pleistocene Epoch within the
last 11,000 years, but not within the recorded history of Orange County, while other faults
have documented historical activity.
The San Andreas fault, noted above, is the largest known active fault in the region in terms
of anticipated events. The closest known fault, as seen on the Regional Geologic Map,
Enclosure A-3, is the Peralta Hills-El Modeno fault location, approximately 5.5 kilometers
(3.5 miles) to the east. The Peralta Fault may tie into the El Modeno Fault, located
approximately 2.8 kilometers (1.8 miles) northeast of the site. W hile little data is available
on the activity and potential of these faults, these reportedly break late Pleistocene (11,000
to 700,000 years old ) materials and may fault Holocene (from 0 to 11,000 years in age)
alluvial materials which would indicate these f aults are active.
The closest known active fault in relation to the site which data is readily available, is the
W hittier-Elsinore fault, which lies approximately 12.7 kilometers (7.8 miles) to the
northeast. The W hittier fault zone extends along the southwestern base of the Puente Hills.
The W hittier fault joins the Chino fault near Prado Dam, and they merge into the Elsinore
fault zone which trends along the eastern base of the Santa Ana Mountains. The 5.9
magnitude W hittier Narrows earthquake of October 1, of 1987, occurred on a previously
unknown concealed thrust fault approximately 20 kilometers east of downtown Los Angeles
that is now associated as part of the W hittier fault system.
Another well known active fault zone is Newport-Inglewood fault zone, located
approximately 16 kilometers (10 miles) to the west-southwest of the site, extends northwest
from offshore Newport Beach to Inglewood (distance of 40 miles) and, like the W hittier fault
and Elsinore faults, has had documented historical activity. The very destructive 1933 Long
Beach earthquake resulted f rom movement along this fault.
Located approximately 37 kilometers (23 miles) to the north is the Cucamonga-Sierra
Madre fault zone, which marks the southern boundary of the San Gabriel Mountains. This
system is comprised of steeply, north-dipping, thrust, range-front faults along which most
of the uplift of the San Gabriel Mountains, has occurred. The Cucamonga fault marks the
eastern portion of the Sierra Madre fault system, which the San Fernando fault marks the
western portion. It is believed that the Cucamonga fault is capable of producing an
earthquake on the order of 7.0 or greater.
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Associated with the San Andreas fault zone, the San Jacinto fault zone lies approximately
55 kilometers (34 miles) to the northeast. The San Jacinto fault zone is a sub-parallel
branch of the San Andreas fault zone, extending from the northwestern San Bernardino
area, southward to the El Centro region. This fault has been active in recent times, with
several large magnitude events. It is believed that the San Jacinto fault is capable of
producing an earthquake magnitude on the order of 6.5 or greater.
Site Geologic Conditions
Fill: As encountered within our exploratory boring placed at the site, fill materials to a depth
of 3 feet are present. These materials mainly consisted of asphalt grindings underlain by
silty sand and lean clay with sand.
Older Alluvium: Underlying the fill materials at the site, older alluvial materials were
encountered within all of our exploratory borings to the maximum depths explored. These
units were noted to consist of lean clay with sand and clayey sand with gravel, and lesser
amounts unit of sandy silt. The older alluvial materials were in a relatively stiff to very stiff
and dense state upon first encounter, becoming very dense/very stiff with depth based on
our equivalent Standard Penetration Test (SPT) data and in-place density testing. Refusal
was experienced at depth of approximately 41 feet due to gravel and possible cobbles.
A detailed description of the subsurface soil conditions as encountered within our
exploratory borings is presented on the Boring Logs within Appendix B.
Groundwater Hydrology
Groundwater was not encountered within our exploratory borings advanced to a maximum
depth of approximately 41 feet below the existing ground surface.
Records for nearby wells which were readily available from the State of California
Department of W ater Resources online database (CDW R, 2020) were reviewed as a part
of this investigation.
This database indicates that the nearest water well is state well number 04S09W 19G001S
which is located approximately 0.7 kilometers (0.4 miles) to the north. This well lies at an
elevation of approximately 179 feet above mean sea level (m.s.l.). Recorded groundwater
measurements were available from 1991 to 2010. The records indicate that groundwater
in this well has fluctuated in depth between approximately 170 feet in November of 1992
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to a high of approximately 91 feet in July of 2006. This results in an approximate elevation
range of 9 feet below m.s.l. to 87 feet above m.s.l. The latest groundwater measurement
of approximately 128 feet was in October of 2010.
As illustrated on Enclosure A-1, the elevation of the site is approximately 180 feet above
mean sea level. Based on the information above, groundwater is anticipated to lie at a
depth greater than 100 f eet in the general site area.
Surface Runoff
Current surface runoff of precipitation waters across the site is generally as sheet flow to
the south-southwest.
Mass Movement
Mass movement features such as landslides, rockfalls, or debris flows within the site
vicinity are not known to exist and no ev idence of mass movement was observed on the
site or in the vicinity during our review of aerial photographs or our site reconnaissance.
Faulting
No active or potentially active faults are known to exist at the subject site. In addition, the
subject site does not lie within a current State of California Earthquake Fault Zone (Hart
and Bryant, 2003).
As previously noted, the nearest known fault is the Peralta/El Modeno faults located
approximately 5.5 kilometers (3.5 miles) to the northeast. However, the activity rating of
these faults is not known. The nearest known active fault in relation to the site is the
W hittier fault. The W hittier fault runs along the base of the Puente Hills to the north. At the
closest approach, this fault lies approximately 12.7 kilometers (7.8 miles) to the
north-northeast. According to a study conducted by Cao et al. (2003), the W hittier fault
within the Elsinore fault system has a slip rate of 2.5 mm per year and is anticipated to be
capable of generating an earthquake with a moment magnitude on the order of 6.8. Other
known active faults in the region include the Newport-Inglewood fault located approximately
16 kilometers (10 miles) to the west-southwest. According to the study conducted by Cao
et al. (2003) the Newport-Inglewood fault has a slip rate of 1 mm per year and an
anticipated magnitude of 7.1.
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The Department of Conservation, California Geological Survey, formerly known as the
Department of Conservation, Division of Mines and Geology, has prepared seismic hazard
zone maps, in accordance with Seismic Hazards Mapping Act for various areas of northern
and southern California. The site and immediate surrounding region are shown on Seismic
Hazard Zone Map of the Orange 7.5 Quadrangle, released April 15, 1998. According to this
map, the site does not lie within an area where historic occurrence of liquefaction, or local
geological, geotechnical, and groundwater conditions indicate a potential for permanent
ground displacements, including earthquake induced landslides, such that mitigation as
defined in Public Resources Code Section 2693(c) w ould be required. Public Resources
Code Section 2693(c) states that "mitigation" means those measures that are consistent
with established practice and that will reduce seismic risk to acceptable levels. An
"acceptable level" is that level that provides reasonable protection of public safety, though
it does not necessarily ensure continued structural integrity and functionality of the project.
Current standards of practice often include a discussion of all potential earthquake sources
within a 100 kilometer (62 mile) radius. However, while there are other large earthquake
faults within a 100 kilometer (62 mile) radius of the site, none of these are considered as
relevant to the site due to the ir greater distance and/or sm aller anticipated magnitudes.
Historical Seismicity
In order to obtain a general perspective of the historical seismicity of the site and
surrounding region a search was conducted for seismic events at and around the area
within various radii. This search was conducted utilizing the historical seismic search
website of the USGS. This website conducts a search of a user selected cataloged seismic
events database, within a specified radius and selected magnitudes, and then plots the
events onto a map. At the time of our search, the database contained data from January
1, 1932 through February 16, 2020.
In our first search, the general seismicity of the region was analyzed by selecting an
epicenter map listing all events of magnitude 4.0 and greater, recorded since 1932, within
a 100 kilometer (62 mile)radius of the site, in accordance with guidelines of the California
Division of Mines and Geology. This map illustrates the regional seismic history of
moderate to large events. As depicted on Enclosure A-4, w ithin Appendix A, the site lies
within a relatively quiet region lying east of the more active region to the west associated
with the Newport-Inglewood fault zone to the west.
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In the second search, the micro seismicity of the area lying within a 15 kilometer (9.3 mile)
radius of the site was examined by selecting an epicenter map listing events on the order
of 2.0 and greater since 1978. In addition, only the “A” events, or most accurate events
were selected. Caltech indicates the accuracy of the “A” events to be approximately 1 km.
The results of this search is a map that presents the seismic history around the area of the
site with much greater detail, not permitted on the larger map. The reason for limiting the
events to the last 40± years on the detail map is to enhance the accuracy of the map.
Events recorded prior the mid 1970's are generally considered to be less accurate due to
advancements in technology. As depicted on this map, Enclosure A-5, while not distinct,
the Newport-Inglewood fault is conspicuous as a northwest trending lineation of small
seismic events located southwest of the site. In addition to these events there is a distinct
band of seismic events north of the site, roughly trending with the W hittier fault zone.
In summary, the historical seismicity of the site entails numerous small to medium
magnitude earthquake events occurring around the subject site, predominately associated
with the presence of the San Jacinto fault zone. Any future developments at the subject
site should anticipate that moderate to large seismic events could occur very near the site.
Secondary Seismic Hazards
Other secondary seismic hazards generally associated with severe ground shaking during
an earthquake include liquefaction, seiches and tsunamis, earthquake induced flooding,
landsliding and rockfalls, and seismic-induced settlement.
Liquefaction: The potential for liquefaction generally occurs during strong ground shaking
within granular loose sediments where the groundwater is usually less than 50 feet. As the
site is underlain by relatively dense/stif f to dense/very stiff deposits of older alluvium and
the depth to groundwater is considered to be greater than 50 feet, the possibility of
liquefaction within these units is considered nil.
Seiches/Tsunamis: The potential for the site to be affected by a seiche or tsunami
(earthquake generated wave) is considered nil due to the absence of any large bodies of
water near the site.
Flooding (W ater Storage Facility Failure): There are no large water storage facilities
located on or upstream near the site which could possibly rupture during an earthquake
and af fect the site by flooding.
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Seismically-Induced Landsliding: Since the site is situated on a relatively flat plain, the
potential f or seismically induced mass movement is considered nil.
Rockfalls: No large, exposed, loose or unrooted boulders that could affect the integrity of
the site are present abov e the site.
Seismically-Induced Settlement: Settlement generally occurs within areas of loose,
granular soils with relatively low density. Since the site is underlain by dense/stif f to
dense/very stiff older alluvial materials, the potential for settlement is considered low. In
addition, the earthwork operations recommended to be conducted during the development
of the site will mitigate any near surface loose soil conditions.
SOILS AND SEISMIC DESIGN CRITERIA (California Building Code 2019)
Design requirements for structures can be found within Chapter 16 of the 2019 California
Building Code (CBC) based on building type, use and/or occupancy. The classification of
use and occupancy of all proposed structures at the site, and thus the design
requirements, shall be the responsibility of the structural engineer and the building official.
For structures at the site to be designed in accordance with the provisions of Chapter 16,
the subject site specif ic criteria is provided below:
Site Classification
Chapter 20 of the ASCE 7-16 defines six possible site classes for earth materials that
underlie any given site. Bedrock is assigned one of three of these six site classes and
these are: A, B, or C. Per ASCE 7-16, Site Class A and Site Class B shall be measured
on-site or estimated by a geotechnical engineer, engineering geologist or seismologist for
competent rock with moderate fracturing and weathering. Site Class A and Site Class B
shall not be used if more than 10 feet of soil is between the rock surface and bottom of the
spread footing or mat foundation. Site Class C can be used for very dense soil and soft
rock with values greater than 50 blows per foot. Site Class D can be used for stiff soil with
values ranging from 15 to 50 blows per foot. Site Class E is for soft clay soils with values
less than 15 blows per foot. Our Standard Penetration Test (SPT) data indicate that the
materials beneath the site are considered Site Class D soils.
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CBC Earthquake Design Summary
As determined in the previous section, earthquake design criteria have been formulated
for the site. However, these values should be reviewed and the final design should be
performed by a qualified structural engineer familiar with the region. Our design values are
provided in Appendix E.
CONCLUSIONS
General
This investigation provides a broad overview of the geotechnical and geologic factors which
are expected to influence future site planning and development. On the basis of our field
investigation and testing program, it is the opinion of LOR Geotechnical Group, Inc., that
the proposed development is feasible from a geotechnical standpoint, provided the
recommendations presented in this report are incorporated into design and implemented
during grading and construction.
The subsurface conditions encountered in our exploratory borings are indicative of the
locations explored. The subsurface conditions presented here are not to be construed as
being present the same everywhere on the site. If conditions are encountered during the
construction of the project which differ significantly from those presented in this report, this
firm should be notified immediately so we may assess the impact to the recommendations
provided.
Foundation Support
Based upon the field investigation and test data, it is our opinion that the existing fill/topsoil
and fill soils will not, in their present condition, provide uniform and/or adequate support
for the proposed improvements. Lef t as is, this condition could cause unacceptable
differential and/or overall settlements upon application of the anticipated foundation loads.
To provide adequate support for the proposed structural improvements, we recommend
that a compacted f ill mat be constructed beneath f ootings and slabs. T his compacted fill
mat will provide a dense, high-strength soil layer to uniformly distribute the anticipated
foundation loads over the underlying soils. In addition, the construction of this compacted
fill mat will allow for the removal of the undocumented fill soils that are present within the
proposed building areas. Conventional foundation systems, using either individual spread
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footings and/or continuous wall footings, will provide adequate support for the anticipated
downward and lateral loads w hen utilized in conjunction with the recommended f ill mat.
Soil Expansiveness
Our laboratory testing found the soils tested to have a medium expansion potential.
Therefore, recommendations for low expansive soils are given in the Foundation Design,
Building Area Slab-on-Grade, and Ex terior Flatwork sections of this report.
Careful evaluation of on-site soils and any import fill for their expansion potential should
be conducted during the grading operation.
Sulfate Protection
The results of the soluble sulfate tests conducted on selected subgrade soils expected to
be encountered at foundation levels indicate that there is a negligible sulfate exposure to
concrete elements in contact with the on site soils per the 2019 CBC. Therefore, no
specific recommendations are given for concrete elements to be in contact with the onsite
soils.
Geologic Mitigations
No special geologic recommendation methods are deemed necessary at this time, other
than the geotechnical recommendations provided in the f ollowing sections.
Seismicity
Seismic ground rupture is generally considered most likely to occur along pre-existing
active faults. Since no known faults are known to exist at, or project into the site, the
probability of ground surf ace rupture occurring at the site is considered nil.
Due to the site’s close proximity to the faults described above, it is reasonable to ex pect
a strong ground motion seismic event to occur during the lifetime of the proposed
development on the site. Large earthquakes could occur on other faults in the general
area, but because of their lesser anticipated magnitude and/or greater distance, they are
considered less significant than the faults described above from a ground motion
standpoint.
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The effects of ground shaking anticipated at the subject site should be mitigated by the
seismic design requirements and procedures outlined in Chapter 16 of the California
Building Code. However, it should be noted that the current building code requires the
minimum design to allow a structure to remain standing after a seismic event, in order to
allow for safe evacuation. A structure built to code m ay still sustain damage which might
ultimately result in the dem olishing of the structure (Larson and Slosson, 1992).
RECOMMENDATIONS
Geologic Recommendations
No special geologic recommendation m ethods are deemed necessary at this time, other
than the geotechnical recommendations provided in the f ollowing sections.
General Site Grading
It is imperative that no clearing and/or grading operations be performed without the
presence of a qualified geotechnical engineer. An on-site, pre-job meeting with the owner,
the developer, the contractor, and geotechnical engineer should occur prior to all grading
related operations. Operations undertaken at the site without the geotechnical engineer
present may result in exclusions of affected areas from the final compaction report for the
project.
Grading of the subject site should be performed in accordance with the following
recommendations as well as applicable portions of the California Building Code, and/or
applicable local ordinances.
All areas to be graded should be stripped of significant vegetation and other deleterious
materials.
It is our recommendation that any existing fills under any proposed flatwork and/or paved
areas be removed and replaced with engineered compacted fill. If this is not done,
premature structural distress (settlement) of the flatwork and pavement may occur. Any
undocumented fills encountered during grading should be completely removed and
cleaned of significant deleterious materials. These may then be reused as compacted fill.
Cavities created by removal of undocumented fill soils and/or subsurface obstructions
should be thoroughly cleaned of loose soil, organic matter and other deleterious materials,
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shaped to provide access for construction equipment, and backfilled as recommended in
the following Engineered Compacted Fill section of this report.
Initial Site Preparation
Any and all existing uncontrolled fills and any loose/soft native alluvial soils should be
removed from structural areas and areas to receive structural fills. The data developed
during this investigation indicates that removals on the order of 5 feet from existing grades
will be required to encounter competent older alluvium. However, deeper removals may be
required locally. Removals should extend horizontally at a distance equal to the depth of
the removals plus proposed fill and at least a minimum of 5 feet. The actual depths of
removals should be determined during the grading operation by observation and/or by in-
place density testing.
Preparation of Fill Areas
After completion of the removals described above and prior to placing fill, the surfaces of
all areas to receive fill should be scarified to a depth of at least 6 inches. The scarified soil
should be brought to near optimum moisture content and compacted to a relative
compaction of at least 90 percent (AST M D 1557).
Preparation of Foundation Areas
All footings should rest upon a minimum of 24 inches of properly compacted fill material
placed over competent natural alluvial soils. In areas where the required fill thickness is not
accomplished by the removal of unsuitable soils, the footing areas should be further
subexcavated to a depth of at least 24 inches below the proposed footing base grade, with
the subexcavation extending at least 5 feet beyond the footing lines. The bottom of this
excavation should then be scarified to a depth of at least 6 inches, brought to between 2
to 4 percent optimum moisture content, and recompacted to at least 90 percent relative
compaction (ASTM D 1557) prior to refilling the excavation to grade as properly compacted
fill. Fill areas should not be constructed so as to place structures across any area where
the maximum depth of fill to minimum depth of fill is greater than a 3:1 ratio.
To provide adequate support, concrete slabs-on-grade should bear on a minimum of 24
inches of compacted soil. The remedial grading recommended above is anticipated to
accomplish the minimum 24 inches of compacted fill. The final pad surfaces should be
rolled to provide smooth, dense surf aces upon which to place the concrete.
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Engineered Compacted Fill
Based upon our preliminary observations and laboratory results, most of the upper site
soils consist of lean clays which have a medium expansion potential. In general, these soils
can be used as structural fills, below foundations, provided that reinforcement measures
are incorporated in the desig n to counteract expansive soil behavior.
Unless approved by the geotechnical eng ineer, rock or similar irreducible material with a
maximum dimension greater than 6 inches should not be buried or placed in f ills.
Import fill, if required, should be inorganic, non-expansive granular soils free from rocks or
lumps greater than 6 inches in maximum dimension. Sources for import fill should be
approved by the geotechnical engineer prior to their use.
Fill should be spread in maximum 8-inch uniform, loose lifts, with each lift brought to 2 to
4 percent above optimum moisture content prior to, during and/or after placement, and
compacted to a relative compaction of at least 90 percent in accordanc e with ASTM D
1557.
Based upon the relative compaction of the near surface soils determined during this
investigation and the relative compaction anticipated for compacted fill soil, we estimate
a compaction shrinkage factor of approximately 10 to 15 percent. Therefore, 1.10 to 1.15
cubic yards of in-place materials would be necessary to yield one cubic yard of properly
compacted fill material. Subsidence is anticipated to be 0.10 feet. These values are for
estimating purposes only, and are exclusive of losses due to stripping or the removal of
subsurface obstructions.
These values may vary due to differing conditions within the project boundaries and the
limitations of this investigation. Shrinkage should be monitored during construction. If
percentages vary, provisions should be made to revise final grades or adjust quantities of
borrow or export.
As previously noted, the on-site clayey soils have potential for expansion. Therefore, a
careful evaluation of on-site and any imported soils for their expansion potential should be
conducted during the grading operation.
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Short-Term Excavations
Following the California Occupational and Safety Health Act (CAL-OSHA) requirements,
excavations 5 feet deep and greater should be sloped or shored. All excavations and
shoring should conf orm to CAL-OSHA requirements.
Short-term excavations 5-feet deep and greater shall conform to Title 8 of the California
Code of Regulations, Construction Safety Orders, Section 1504 and 1539 through 1547.
Based on our exploratory borings, it appears that Type C soil is the predominant type of
soil on the project and all short-term excavations should be based on this type of soil.
Deviation from the standard short-term slopes are permitted using Option 4, Design by a
Registered Professional Engineer (Section 1541.1).
Short-term slope construction and maintenance are the responsibility of the contractor, and
should be a consideration of his methods of operation and the actual soil conditions
encountered.
Slope Construction
Preliminary data indicates that cut and fill slopes should be constructed no steeper than
two horizontal to one vertical. Fill slopes should be overfilled during construction and then
cut back to expose fully compacted soil. A suitable alternative would be to compact the
slopes during construction, then roll the final slopes to provide dense, erosion-resistant
surfaces.
Slope Protection
Since the site soils are susceptible to erosion by running water, measures should be
provided to prevent surface water from flowing over slope faces. Slopes at the project
should be planted with a deep rooted ground cover as soon as possible after completion.
The use of succulent ground covers such as iceplant or sedum is not recommended. If
watering is necessary to sustain plant growth on slopes, the watering system should be
monitored to assure proper operation and to prev ent over watering.
Foundation Desig n
Since the site is underlain by medium expansive soils, we recommend that the planned
buildings be supported on reinforced, stiffened slab foundations resting over 24 inches of
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engineered compacted fill placed over competent older alluvium. The design of the slab
foundation could be performed in conformance to the Wire Reinforcement Institute (WRI)
method or the Post-Tensioning Institute (PTI) method.
For the application of the WRI method, an average, effective plasticity index of 18 is
recommended for foundation design. The slab thickness should be a minimum of 4 inches
and should have a reinforcement of at least Asfy equal to 2,900 pounds. This could consist
of #3 reinforcing bars of 60-grade steel placed at a maximum spacing of 18 inches on
center, each way or equivalent. Interior stiffening concrete beams should be placed at a
spacing not to exceed 17 feet. External concrete beams should be provided around the
perimeter of the slab. The minimum beam dimensions should be 24 inches high and 12
inches wide, and embedded approximately 18 inches below the lowest adjacent grade. The
beams should be properly reinforced to resist the moment and shears caused by the
differential heave of the expansive soil. Minimum beam reinforcement should be two #5
rebars at top of beam and two #5 rebars at bottom. Stirrups may be added, particularly in
the perimeter beams, to account for concentrated and exterior wall loads. These
reinforcement, depth, and spacing recommendations should be considered minimum. The
actual requirements for slab-on-grade foundations design and construction should be
provided by a structural engineer experienced in these matters.
The above recommendations were developed for medium expansive soils with an average,
effective plasticity index of 18. These conditions should be verified during the site grading
by additional evaluation of on-site and any imported soils for their expansion potential and
plasticity characteristics.
If slab-on-grade foundations per the PTI method are proposed, the following geotechnical
parameters should be used for design:
• Edge Moisture Variation Distance, em:
Center Lift Loading Conditions:9.0 ft
Edge Lift Loading Conditions:7.5 ft
• Differential Swell, ym:
Center Lift 0.3 in
Edge Lift 0.65 in
• Subgrade Soil Friction Coefficient, µ: 0.30
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The above design parameters are based upon the data collected during our site
investigation and are in accordance with Design of Post-Tensioned Slabs-on-Ground, third
edition, published by the Post-Tensioning Institute.
For preliminary sizing of foundations, we recommend an allowable bearing pressure of
1,500 pounds per square foot (psf) to be utilized for foundations with a minimum width of
12 inches and a m inimum depth of 18 inches below lowest adjacent grade. This bearing
pressure may be increased by 200 psf for each additional foot of width, and by 400 psf for
each additional f oot of depth, up to a m aximum of 4,000 psf .
The above values are net pressures; therefore, the weight of the foundations and the
backfill over the foundations may be neglected when computing dead loads. The values
apply to the maximum edge pressure for foundations subjected to eccentric loads or
overturning. The recommended pressures apply for the total of dead plus frequently
applied live loads, and incorporate a factor of safety of at least 3.0. The allowable bearing
pressures may be increased by one-third for temporary wind or seismic loading. The
resultant of the combined vertical and lateral seismic loads should act within the middle
one-third of the footing width. The maximum calculated edge pressure under the toe of
foundations subjected to eccentric loads or overturning should not exceed the increased
allowable pressure.
Resistance to lateral loads will be provided by passive earth pressure and base friction. For
foundations bearing against compacted fill, passive earth pressure may be considered to
be developed at a rate of 300 pounds per square foot per foot of depth. Base friction may
be computed at 0.30 times the normal load. Base friction and passive earth pressure may
be combined without reduction. These values are for dead load plus live load and may be
increased by one-third f or wind or seismic loading.
Settlement
Total settlement of individual foundations will vary depending on the width of the foundation
and the actual load supported. Maximum settlement of shallow foundations designed and
constructed in accordance with the preceding recommendations are estimated to be on the
order of 0.5 inch. Differential settlements between adjacent footings should be about one-
half of the total settlement. Settlement of all foundations is expected to occur rapidly,
primarily as a result of elastic compression of supporting soils as the loads are applied, and
should be essentially completed shortly after initial application of the loads.
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Building Area Slab-On-Grade
To provide adequate support, concrete slabs-on-grade should bear on a minimum of 24
inches of compacted soil placed and maintained at 2 to 4 percent above optimum moisture
content. The final pad surfaces should be rolled to provide smooth, dense surfaces.
Concrete slabs-on-grade should be a minimum of 5 inches in thickness with No. 4 bars
spaced 12 inches on center each way. A 4-inch rock base should also be installed beneath
the slab.
Slabs to receive moisture-sensitive coverings should be provided with a moisture vapor
retarder/barrier. W e recommend that a vapor retarder/barrier be designed and constructed
according to the American Concrete Institute 302.1R, Concrete Floor and Slab
Construction, which addresses moisture vapor retarder/barrier construction. At a minimum,
the vapor retarder/barrier should comply with ASTM E1745 and have a nominal thickness
of at least 10 mils. The vapor retarder/barrier should be properly sealed, per the
manufacturer's recommendations, and protected from punctures and other damage. Per
the Portland Cement Association (www.cement.org/tech/cct_con_vapor_retarders.asp),
for slabs with vapor-sensitive coverings, a layer of dry, granular material (sand) should be
placed under the vapor retarder/barrier. For slabs in humidity-controlled areas, a layer of
dry, granular material (sand) should be placed abov e the vapor retarder/barrier.
The slabs should be protected from rapid and excessive moisture loss which could result
in slab curling. Careful attention should be given to slab curing procedures, as the site area
is subject to large temperature extremes, humidity, and strong winds.
Exterior Flatwork
To provide adequate support, exterior flatwork improvements should rest on a minimum
of 12 inches of soil compacted to at least 90 percent (AST M D 1557).
If medium expansive soils are found underlying flatwork areas, these areas should be
pre-soaked to approximately 4 percent above the optimum moisture content to a minimum
depth of 18 inches.
General flatwork such as sidewalk, patios, curbs, etc., should have a thickness of at least
4 inches, with saw cuts every 10 feet or less. Driveways should be at least 6-inch thick,
with saw cuts every 15 feet or less.
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Reinforcement should be provided for all sidewalks, patio slabs, and driveways with a
minimum dimension greater than 5 feet. This should consist of #3 rebars of 60-grade steel
placed at a maximum spacing of 18 inches on center, each way Reinforcement for curbing
should be one continuous #4 rebars at top and bottom .
Flatwork surface should be sloped a minimum of 1 percent away from buildings and
slopes, to approved drainage structures.
W all Pressures
The design of footings for retaining structures should be performed in accordance with the
recommendations described earlier under Preparation of Foundation Areas and
Foundation Design. For design of retaining wall footings, the resultant of the applied loads
should act in the middle one-third of the footing, and the maximum edge pressure should
not exceed the basic allowable value without increase.
For design of retaining walls unrestrained against movement at the top, we recommend an
equivalent fluid density of 37 pounds per cubic foot (pcf) be used. This assumes level
backfill consisting of recompacted, non-expansive, soils placed against the structures and
with the backcut slope extending upward from the base of the stem at 35 degrees from the
vertical or flatter.
To avoid overstressing or excessive tilting during placement of backfill behind walls, heavy
compaction equipment should not be allowed within the zone delineated by a 45 degree
line extending from the base of the wall to the f ill surface.
The backfill directly behind the walls should be compacted using light equipment such as
hand operated vibrating plates and rollers. No material larger than 3-inches in diameter
should be placed in direct contact w ith the wall.
W all pressures should be verified prior to construction, when the actual backfill materials
and conditions have been determined. Recommended pressures are applicable only to
level, non-expansive, properly drained backf ill (with no additional surcharge loadings).
If inclined backfills are proposed, this firm should be contacted to develop appropriate
active earth pressure parameters. Toe bearing pressure for non-structural walls on soils,
not prepared as described earlier under Preparation of Foundation Areas, should not
exceed Calif ornia Building Code values.
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The parameters given above are based on the assumption that granular, non-expansive,
compacted sandy soils will be used as wall backfills. The preceding parameters were
developed assuming that the sandy backfill material may have a friction angle of
approximately 32 degrees and a compacted moist unit weight of approximately 120 pcf.
These materials may likely will require importation to the site. Much of the surficial site soils
are expansive clayey materials which normally have low permeability, uncertain behavior,
and exert higher lateral earth pressures on retaining structures. Therefore, we recommend
that these soils do not be used w ithin wall backfill areas.
Sulfate Protection
The results of the soluble sulfate tests conducted on selected subgrade soils expected to
be encountered at f oundation levels are presented on Enclosure C.
Based on the test results it appears that there is a negligible sulfate exposure to concrete
elements in contact with on site soils. T he CBC, therefore, does not recommend special
design criteria f or concrete elements in conduct with such materials.
Preliminary Pavement Design
Testing and design for preliminary on-site pavement was conducted in accordance with the
California Highway Design Manual. Based upon our preliminary sampling and testing, and
upon a Traffic Index typical for such projects, it appears that the structural section
tabulated below should provide satisfactory pavement for the subject pavement
improvements:
AREA T.I.DESIGN
R-VALUE PRELIMINARY SECTION
Parking and Drive Areas (light
vehicular traffic and occasional
truck traffic)
6.0 5 0.25’ AC/1.15' AB
AC - Asphalt Concrete
AB - Class 2 Aggregate Base
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The above structural section is predicated upon 90 percent relative compaction (ASTM D
1557) of all utility trench backfills and 95 percent relative compaction (ASTM D 1557) of
the upper 12 inches of pavement subgrade soils and of any aggregate base utilized. In
addition, the aggregate base should meet Caltrans specifications for Class 2 Aggregate
Base.
In areas of the pavement which will receive high abrasion loads due to start-ups and stops,
or where trucks will move on a tight turning radius, consideration should be given to
installing concrete pads. Such pads should be a minimum of 0.5-foot thick concrete, with
a 0.35-foot thick aggregate base. Concrete pads are also recommended in areas adjacent
to trash storage areas where heavier loads will occur due to operation of trucks lifting trash
dumpsters. The recommended 0.5 feet thick portland cem ent concrete (PCC) pavement
section should have a minimum modulus of rupture (MR) of 550 pounds per square inch
(psi).
It should be noted that all of the above pavement design was based upon the results of
preliminary sampling and testing, and should be verified by additional sampling and testing
during construction when the actual subg rade soils are exposed.
Construction Monitoring
Post investigative services are an important and necessary continuation of this
investigation. Project plans and specifications should be reviewed by the project
geotechnical consultant prior to construction to confirm that the intent of the
recommendations presented herein have been incorporated into the design. Additional
expansion index, R-value, and soluble sulfate testing may be required during site rough
grading.
During construction, sufficient and timely geotechnical observation and testing should be
provided to correlate the findings of this investigation with the actual subsurface conditions
exposed during construction. Items requiring observation and testing include, but are not
necessarily limited to, the f ollowing:
1.Site preparation-stripping and removals.
2.Excavations, including approval of the bottom of excavation prior to filling.
3.Scarifying and recompacting prior to fill placement.
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4.Subgrade preparation f or pavements and slabs-on-g rade.
5.Placement of engineered compacted fill and backfill, including approval of fill
materials and the performance of sufficient density tests to evaluate the degree of
compaction being achieved.
6.Foundation ex cavations.
LIMITATIONS
This report contains geotechnical conclusions and recommendations developed solely for
use by C & C Development, and their design consultants, for the purposes described
earlier. It may not contain sufficient information for other uses or the purposes of other
parties. The contents should not be extrapolated to other areas or used for other facilities
without consulting LOR Geotechnical Group, Inc.
The recommendations are based on interpretations of the subsurface conditions concluded
from information gained from subsurface explorations and a surficial site reconnaissance.
The interpretations may differ from actual subsurface conditions, which can vary
horizontally and vertically across the site. If conditions are encountered during the
construction of the project which differ significantly from those presented in this report, this
firm should be notified immediately in order that we may assess the impact to the
recommendations provided.
Due to possible subsurface variations, all aspects of field construction addressed in this
report should be observed and tested by the project geotechnical consultant.
If parties other than LOR Geotechnical Group, Inc., provide construction monitoring
services, they must be notified that they will be required to assume responsibility for the
geotechnical phase of the project being completed by concurring with the
recommendations provided in this report or by providing alternative recommendations.
The report was prepared using generally accepted geotechnical engineering practices
under the direction of a state licensed geotechnical engineer. No warranty, expressed or
implied, is made as to conclusions and prof essional advice included in this report.
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Any persons using this report for bidding or construction purposes should perform such
independent investigations as deemed necessary to satisfy themselves as to the surface
and subsurface conditions to be encountered and the procedures to be used in the
performance of work on this project.
TIME LIMITATIONS
The findings of this report are valid as of this date. Changes in the condition of a property
can, however, occur with the passage of time, whether they be due to natural processes
or the work of man on this or adjacent properties. In addition, changes in the Standards-of-
Practice and/or Governmental Codes may occur. Due to such changes, the findings of this
report may be invalidated wholly or in part by changes beyond our control. Therefore, this
report should not be relied upon after a significant amount of time without a review by LOR
Geotechnical Group, Inc., verifying the suitability of the conclusions and recommendations.
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REFERENCES
American Society of Civil Engineers, 2016, Minimum Design Load for Buildings and other
Structures, ASCE 7-16.
California Building Standards Commission, 2019, Calif ornia Building Code.
C a l i f o r n i a D e p a r t m e n t o f W a t e r R e s o u r c e s , 2 0 2 0 ,
http://www.water.ca.gov/waterdatalibrary/.
California Division of Mines and Geology, 1998, Seismic Hazards Zone Map, Orange
Quadrangle.
Google Earth, 2020, Im agery from various years, www.google.com/earth.
Hart, E.W . and W .A. Bryant, 1997, revised 2003, Fault-Rupture Hazard Zones in California,
Alquist-Priolo Earthquake Fault Zoning Act with Index to Earthquake Fault Zones Maps:
California Dept. of Conservation Division of Mines and Geology Special Publication 42,
Revised Edition with Supplements 1, 2 and 3.
Historic Aerials, 2020, Im agery from various years, www.historicaerials.com.
IDE Arc Architecture and Planning, 2019, Architectural Site Plan, City Yard, dated
September 12, 2019.
Larson, R., and Slosson, J., 1992, The Role of Seismic Hazard Evaluation in Engineering
Reports, in Engineering Geology Practice in Southern California, AEG Special Publication
Number 4, pp 191-194.
Morton, D.M. and Matti, J.C., 2006, Geologic Map of the San Bernardino and Santa Ana
30' X 60' Quadrang les, California, Open-File Report 2006-1217.
OSPHD, 2020 ,US Seism ic Design Maps, https://seism icmaps.org.
U.S.G.S., 2020, https://earthq uake.usgs.gov/earthquakes/search/.
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APPENDIX A
Index Map, Architectural Site Plan,
Regional Geologic Map,
and
Historical Seismicity Maps
LOR GEOTECHNICAL GROUP, INC.
APPENDIX B
Field Investigation Program and Boring Logs
LOR GEOTECHNICAL GROUP, INC.
APPENDIX B
FIELD INVESTIGATION
Subsurface Exploration
The site was investigated on February 4, 2020 and consisted of advancing 6 exploratory
borings to depths from approximately 15 feet and 41 feet below the existing ground
surface. The approximate locations of the borings are shown on Enclosure A-2, within
Appendix A.
The drilling exploration was conducted using a truck-mounted Mobile B-61 drill rig equipped
with 8-inch diameter hollow stem augers. The soils were continuously logged by our
geologist who inspected the site, created detailed logs of the borings, obtained
undisturbed, as well as disturbed, soil samples for evaluation and testing, and classified
the soils by visual examination in accordance with the Unified Soil Classification System.
Relatively undisturbed samples of the subsoils were obtained at a maximum interval of 5
feet. The samples were recovered by using a California split barrel sampler of 2.50 inch
inside diameter and 3.25 inch outside diameter or a Standard Penetration Sampler (SPT)
from the ground surface to the total depth explored. The samplers were driven by a 140
pound automatic trip hammer dropped from a height of 30 inches. The number of hammer
blows required to drive the sampler into the ground the final 12 inches were recorded and
further converted to an equivalent SPT N-value. Factors such as efficiency of the automatic
trip hammer used during this investigation (80%), borehole diameter (8"), and rod length
at the test depth were considered for further computing of equivalent SPT N-values
corrected for field procedures ( N60) which are included in the boring logs, Enclosures B-1
through B-6.
The undisturbed soil samples were retained in brass sample rings of 2.42 inches in
diameter and 1.00 inch in height, and placed in sealed containers. Disturbed soil samples
were obtained at selected levels within the borings and placed in sealed containers for
transport to the laboratory.
All samples obtained were taken to our geotechnical laboratory for storage and testing.
Detailed logs of the borings are presented on the enclosed Boring Logs, Enclosures B-1
through B-6. A Boring Log Legend and Soil Classification Chart are presented on
Enclosures B-L and B-ii, respectively.
B
LOR *(27(&+1,&$/*5283,1&
CONSISTENCY OF SOIL
SANDS
SPT BLOW S CONSISTENCY
0 -4 V ery Loose
4 -1 0 Loose
1 0 -3 0 M edium Dense
3 0 -5 0 Dense
Ov er 5 0 V ery Dense
COHESIV E SOILS
SPT BLOW S CONSISTENCY
0 -2 V ery Sof t
2 -4 Sof t
4 -8 M edium
8 -1 5 St if f
1 5 -3 0 V ery St if f
3 0 -6 0 Hard
Ov er 6 0 V ery Hard
SAM PLE KEY
Symbol Descript ion
INDICA TES CA LIFORNIA
SPLIT SPOON SOIL
SA M PLE
INDICA TES BULK SA M PLE
INDICA TES SA ND CONE
OR NUCLEA R DENSITY
TEST
INDICA TES STA NDA RD
PENETRA TION TEST (SPT)
SOIL SA M PLE
TYPES OF LABORATORY TESTS
1 A t t erberg Limit s
2 Consolidat ion
3 Direc t Shear (undist urbed or remolded)
4 Ex pansion Index
5 Hy drom et er
6 Organic Cont ent
7 Proct or (4 ", 6 ", or Cal2 1 6 )
8 R-v alue
9 Sand Equiv alent
1 0 Siev e A naly sis
1 1 Soluble Sulf at e Cont ent
1 2 Sw ell
1 3 W ash 2 0 0 Siev e
BORING LOG LEGEND
PROJECT:637 W. STRUCK AVENUE, ORANGE, CALIFORNIA PROJECT NO.: 33616.1
CLIENT:C & C DEVELOPMENT ENCLOSURE:B-i
LOR Geotechnical Group, Inc.DATE:FEBRUARY 2020
PA RTICLE SIZE LIM ITS
BOULDERS COBBLES
GRAV EL SAND
SILT OR CLAY
COARSE FINE COARSE M EDIUM FINE
1 2" 3" 3/4 " No. 4 No. 10 No. 40 20 0
(U.S. STANDARD SIEVE SIZE)
SOIL CLASSIFICATION CHART
PROJECT 637 W. STRUCK AVENUE, ORANGE, CALIFORNIA PROJECT NO. 33616.1
CLIENT:C & C DEVELOPMENT ENCLOSURE:B-ii
LOR Geotechnical Group, Inc.DATE:FEBRUARY 2020
113.3
121 for 9"
124
121
15.7
5.2
4.2
16.7
3.4
14.7
5.7
3.2
5.5
@ 1 foot, OLDER ALLUVIUM: LEAN CLAY with SAND,
approximately 15% fine grained sand, 85% clayey fines of
low to medium plascitity, red brown, damp, some pinhole
porosity.
16
@ 5 feet, CLAYEY SAND with GRAVEL, approximately 15%
gravel to 2", 20% coarse grained sand, 20% medium grained
sand, 25% fine grained sand, 20% clayey fines of low
plasticity, red brown, damp.
B-1
@ 12 feet, difficult drilling
@ 15 feet, LEAN CLAY with SAND, approximately 5% coarse
grained sand, 10% medium grained sand, 15% fine grained
sand, 70% clayey fines of low plasticity, light red brown,
moist.
@ 20 feet, CLAYEY SAND with GRAVEL, approximately 30%
gravel to 3", 15% coarse grained sand, 15% medium grained
sand, 20% fine grained sand, 20% clayey fines of low
plasticity, red brown, dry.
@ 25 feet, some 2 to 3" thick LEAN CLAY with SAND layers,
increase in overal moisture content.
@ 30 feet, some 4 to 6" thick SILTY SAND with trace clay
layers , decrease in overall moisture content.
@ 35 feet, remains difficult to drill.
END OF BORING @ 41' due to refusal on gravel and possible
cobbles
Fil to 1'
No groundwater
No bedrock
@ 0 feet, 3/4" gravel with silt and some asphalt concrete debris.
111.0
117.4
112.0
113.8
108.7
CL
SC
CL
SC
24
68
11
37
77 @ 10 feet, increase in gravel to approximately 35% and to 3",
dry.SPT33616.1
DESCRIPTIONLABORATORY TESTSGEOTECHNICAL GROUP INC.BLOW COUNTSCLIENT:
February 4, 2020
C & C Development Co., LLC(%)MOISTURE CONTENT0
5
10
15
20
25
30
35
40
45
@ 2 feet, contains trace coarse and medium grained sand, no
visible porosity, moist.(PCF)1, 3, 4,
7, 8, 9,
10, 11
TEST DATA
LOG OF BORING B-1
Mobile B-61DRY DENSITYSAMPLE TYPEEQUIPMENT:
PROJECT NUMBER:
8"ENCLOSURE:HOLE DIA.:
Proposed Apartment ComplexU.S.C.S.DATE DRILLED:
ELEVATION:DEPTH IN FEETPROJECT:LITHOLOGY
@ 0.66 feet, OLDER ALLUVIUM: LEAN CLAY with SAND,
approximately 10% medium grained sand, 15% fine grained
sand, 75% clayey fines of low plasticity, red brown, damp.
90
51
15.9
4.7
6.2
5.3
17.4
16.1
3.1
1.4
13
@ 0.30 feet, AGGREGATE BASE, 0.33' thick.
16
@ 2 feet, becomes moist.
111.2
@ 7 feet, rings disturbed.
B-2
@ 15 feet, no visible porosity.
@ 19 feet, CLAYEY SAND with GRAVEL, approximately 30%
gravel to 3", 15% coarse grained sand, 15% medium grained
sand, 20% fine grained sand, 20% clayey fines of low
plasticity, red brown, dry.
@ 25 feet, rings disturbed, cobble in tip of sampler.
END OF BORING @ 25.5'
No fill
No groundwater
No bedrock
@ 0 feet, ASPHALT CONCRETE, 0.30' thick.
121.7
110.5
109.7
114.8
116.6
CL
SC
CL
SC
25
@ 12 feet, LEAN CLAY with SAND, trace coarse grained sand,
trace medium grained sand, 10% fine grained sand, 90%
clayey fines of low plasticity, red brown, moist, some pinhole
porosity.
10
23
22 LABORATORY TESTSDESCRIPTIONBLOW COUNTSGEOTECHNICAL GROUP INC.
CLIENT:
@ 5 feet, CLAYEY SAND with GRAVEL, approximately 25%
gravel to 3", 15% coarse grained sand, 15% medium grained
sand, 20% fine grained sand, 25% clayey fines of low
plasticity, red brown, damp.SPTFebruary 4, 2020MOISTURE CONTENT0
5
10
15
20
25
30
33616.1(%)LITHOLOGYTEST DATA
LOG OF BORING B-2
Mobile B-61
HOLE DIA.:DRY DENSITY(PCF)U.S.C.S.C & C Development Co., LLC
Proposed Apartment Complex PROJECT NUMBER:
8"SAMPLE TYPEENCLOSURE:
PROJECT:
EQUIPMENT:
DATE DRILLED:
ELEVATION:DEPTH IN FEET
@ 0 feet, ASPHALT CONCRETE GRINDINGS.
18
30
17
15
16
90
51 for 4"
17.4
15.9
7.1
7.0
16.8
4.1
111.7 @ 1 foot, ASPHALT CONCRETE GRINDINGS.
B-3
@ 5 feet, trace gravel to 1.5".
@ 7 feet, CLAYEY SAND with GRAVEL, approximately 25%
gravel to 2", 15% coarse grained sand, 15% medium grained
sand, 25% fine grained sand, 20% clayey fines of low
plasticity, red brown, damp.
@ 10 feet, WELL GRADED SAND layer, 0.25' thick.
@ 12 feet, LEAN CLAY with SAND, approximately 5%
medium grained sand, 10% fine grained sand, 85% clayey
fines of low plasticity, red brown, moist.
@ 20 feet, CLAYEY SAND with GRAVEL, approximtely 30%
gravel to 2", 15% coarse grained sand, 15% medium grained
sand, 20% fine grained sand, 20% clayey fines of low
plasticity, red brown, damp.
@ 25 feet, no recovery.
END OF BORING @ 26.33'
Fill to 2'
No groundwater
No bedrock
12.1
115.8
121.0
115.0
104.5
116.5
123.0
SM
CL
SC
SW
SC
CL
SC
17
@ 2 feet, OLDER ALLUVIUM: LEAN CLAY with SAND,
approximately 5% medium grained sand, 10% fine grained
sand, 85% clayey fines of low plasticity, red brown, moist.
CLIENT:
February 4, 2020
C & C Development Co., LLCLABORATORY TESTSBLOW COUNTS33616.1SPT(%)0
5
10
15
20
25
30 MOISTURE CONTENT@ 0.5 feet, FILL: SILTY SAND, approximately 25% coarse
grained sand, 25% medium grained sand, 25% fine grained
sand, 25% silty fines with trace clay, red brown, damp.(PCF)TEST DATA
LOG OF BORING B-3
Mobile B-61GEOTECHNICAL GROUP INC.DRY DENSITYDESCRIPTION
PROJECT NUMBER:
8"ENCLOSURE:
Proposed Apartment Complex
HOLE DIA.:
DATE DRILLED:SAMPLE TYPEELEVATION:DEPTH IN FEETPROJECT:LITHOLOGYU.S.C.S.EQUIPMENT:
END OF BORING @ 21.5'
Fill to 3'
No groundwater
No bedrock
15.1
16.3
11.9
3.9
4.6
9.6
@ 0 feet, ASPHALT CONCRETE GRINDINGS.
@ 1.5 feet, FILL: LEAN CLAY with SAND, approximately 10%
gravel to 1", 25% coarse grained sand, 25% medium grained
sand, 25% fine grained sand, 15% clayey fines of low
plasticity, gray brown.
@ 3 feet, OLDER ALLUVIUM: LEAN CLAY with SAND,
approximately 5% coarse grained sand, 10% medium
grained sand, 10% fine grained sand, 75% clayey fines of low
plasticity, red brown, moist, trace pinhole porosity.
@ 7 feet, CLAYEY SAND with GRAVEL, approximately 20%
gravel to 1.5", 15% coarse grained sand, 15% medium
grained sand, 15% fine grained sand, 35% clayey fines of low
plasticity, red brown, moist.
@ 18.5 feet, LEAN CLAY with SAND layer, approximately 5%
coarse grained sand, 10% medium grained sand, 15% fine
grained sand, 70% clayey fines of low plasticity, red brown,
damp.
46
114.1
B-4
9, 10, 11
TEST DATA
LOG OF BORING B-4
Mobile B-61
@ 10 feet, increase in gravel, rings disturbed, damp.
110.7
111.5
126.1
125.5
CL
SC
CL
SC46
52
17
19
44
February 4, 2020BLOW COUNTS(%)DESCRIPTIONMOISTURE CONTENTGEOTECHNICAL GROUP INC.LABORATORY TESTS0
5
10
15
20
25
33616.1
CLIENT:
HOLE DIA.:DRY DENSITY(PCF)SAMPLE TYPEU.S.C.S.LITHOLOGYPROJECT:SPTELEVATION:C & C Development Co., LLCDEPTH IN FEETDATE DRILLED:
PROJECT NUMBER:
8"ENCLOSURE:
Proposed Apartment Complex
EQUIPMENT:
TEST DATA
U.S.C.S.@ 7 feet, some gravel.
@ 10 feet, CLAYEY SAND with GRAVEL, approximately 25%
gravel to 3", 15% coarse grained sand, 15% medium grained
sand, 20% fine grained sand, 25% clayey fines of low
plasticity, red brown, dry, somewhat difficult drilling.
@ 15 feet, no recovery, cobble in tip of sampler.
END OF BORING @ 15.25'
Fill to 2'
No groundwater
No bedrock
@ 0.25 feet, FILL: SILTY SAND, approximately 15% coarse
grained sand, 25% medium grained sand, 25% fine grained
sand, 35% silty fines, black.
@ 0 feet, ASPHALT GRINDINGS.
LOG OF BORING B-5
Mobile B-61
128.3
B-5HOLE DIA.:DRY DENSITY(PCF)SAMPLE TYPE118.3
109.6
SM
CL
SC
@ 2 feet, OLDER ALLUVIUM: LEAN CLAY with SAND, trace
gravel to 1/2", approximately 5% coarse grained sand, 10%
medium grained sand, 10% fine grained sand, 75% clayey
fines of low plasticity, red brown, moist.
20
27
55
46 for 4"
15.3
13.0
4.1MOISTURE CONTENTLITHOLOGY33616.1(%)0
5
10
15
20
February 4, 2020
CLIENT:
GEOTECHNICAL GROUP INC.
DESCRIPTIONDEPTH IN FEETENCLOSURE:
EQUIPMENT:SPTDATE DRILLED:
Proposed Apartment Complex
ELEVATION:
8"
PROJECT:
C & C Development Co., LLCLABORATORY TESTSBLOW COUNTSPROJECT NUMBER:
DRY DENSITY4.4
@ 0 feet, ASPHALT GRINDINGS.
@ 0.33 feet, OLDER ALLUVIUM: CLAYEY SAND with
GRAVEL, approximately 25% gravel to 2",15% coarse
grained sand, 15% medium grained sand, 25% fine grained
sand, 20% clayey fines of low plasticity, red brown, damp.
@ 15 feet, LEAN CLAY with SAND, approximately 5% coarse
grained sand, 10% medium grained sand, 15% fine grained
sand, 70% clayey fines of low plasticity, red brown, moist.
@ 20 feet, SANDY SILT, approximately 40% fine grained sand,
60% silty fines with trace clay.
@ 25 feet, some gravel, dry.
END OF BORING @ 25.5'
No fill
No groundwater
No bedrock
17.2
4.9
SC
B-6
LOG OF BORING B-6
Mobile B-61
HOLE DIA.:
CL
ML15.3
TEST DATA
40
30
53
13
20
73
5.0
6.0 (%)MOISTURE CONTENT0
5
10
15
20
25
30 (PCF)7SPT
33616.1
February 4, 2020
CLIENT:
GEOTECHNICAL GROUP INC.
DESCRIPTIONLITHOLOGY
ELEVATION:
DATE DRILLED:DEPTH IN FEETBLOW COUNTSProposed Apartment ComplexPROJECT:
ENCLOSURE:
EQUIPMENT:U.S.C.S.LABORATORY TESTSC & C Development Co., LLC
PROJECT NUMBER:
8"SAMPLE TYPE
APPENDIX C
Laboratory Testing Program and Test Results
LOR GEOTECHNICAL GROUP, INC.
APPENDIX C
LABORATORY TESTING
General
Selected soil samples obtained from our borings were tested in our geotechnical laboratory
to evaluate the physical properties of the soils affecting foundation design and construction
procedures. The laboratory testing program performed in conjunction with our investigation
included in-place moisture content and dry density, laboratory compaction characteristics,
direct shear, sieve analysis, sand equivalent, R-value, expansion index, Atterberg limits,
and soluble sulfate content. Descriptions of the laboratory tests are presented in the
following paragraphs:
Moisture Density Tests
The moisture content and dry density information provides an indirect measure of soil
consistency for each stratum, and can also provide a correlation between soils on this site.
The dry unit weight and field moisture content were determined for selected undisturbed
samples, in accordance with ASTM D 2922 and ASTM D 2216, respectively, and the
results are shown on the Boring Logs, Enclosures B-1 through B-6 for convenient
correlation with the soil profile.
Laboratory Compaction
Selected soil samples were tested in the laboratory to determine compaction
characteristics using the ASTM D 1557 compaction test method. The results are presented
in the following table:
LABORATORY COMPACTION
Boring
Number
Sample
Depth
(feet)
Soil Description
(U.S.G.S.)
Maximum
Dry Density
(pcf)
Optimum
Moisture
Content
(percent)
B-1 1-4 (CL) Lean Clay with Sand 126.5 11.0
B-6 6-9 (SC) Clayey Sand 134.5 6.5
C
LOR*(27(&+1,&$/*5283,1&
Direct Shear Tests
Shear tests are performed with a direct shear machine in general accordance with ASTM
D 3080 at a constant rate-of-strain (usually 0.04 inches/minute). The machine is designed
to test a sample partially extruded from a sample ring in single shear. Samples are tested
at varying normal loads in order to evaluate the shear strength parameters, angle of
internal friction and cohesion. Samples are tested in a remolded condition (90 percent
relative compaction per ASTM D 1557) and soaked, to represent the worst case conditions
expected in the field.
The results of the shear tests are presented in the following table:
DIRECT SHEAR TESTS
Boring
Number
Sample Depth
(feet)
Soil Description
(U.S.G.S.)
Angle of
Internal Friction
(degrees)
Apparent
Cohesion
(psf)
B-1 1-4 (CL) Lean Clay with Sand 31 700
Sieve Analysis
A quantitative determination of the grain size distribution was performed for selected
samples in accordance with the ASTM D 422 laboratory test procedure. The determination
is performed by passing the soil through a series of sieves, and recording the weights of
retained particles on each screen. The results of the sieve analyses are presented
graphically on Enclosure C-1.
Sand Equivalent
The sand equivalent of selected soils were evaluated using the California Sand Equivalent
Test Method, Caltrans Number 217. The results of the sand equivalent tests are presented
with the grain size distribution analyses on Enclosure C-1.
R-Value Test
Soil samples were obtained at probable pavement subgrade level and was tested to
determine its R-value using the California R-Value Test Method, Caltrans Number 301. The
results of the R-value test is presented on Enclosure C-1.
C
LOR *(27(&+1,&$/*5283,1&
Expansion Index Tests
Remolded samples are tested to determine their expansion potential in accordance with
the Expansion Index (EI) test. The test is performed in accordance with the Uniform
Building Code Standard 18-2. The test results are presented in the following table:
EXPANSION INDEX TESTS
Boring
Number
Sample
Depth
(feet)
Soil Description
(U.S.C.S.)
Expansion
Index
(EI)
Expansion
Potential
B-1 1-4 (CL) Lean Clay with Sand 56 Medium
Expansion Index: 0-20 21-50 51-90 91-130
Expansion Potential: Very low Low Medium High
Atterberg Limits
Selected samples of the fine-grained soil units encountered at the site are tested for their
Atterberg limits in accordance with ASTM D 4318. The results of these tests are presented
on Enclosure C-2.
Soluble Sulfate Content Tests
The soluble sulfate content of selected subgrade soils was evaluated and the
concentration of soluble sulfates in the soils was determined by measuring the optical
density of a barium sulfate precipitate. The precipitate results from a reaction of barium
chloride with water extractions from the soil samples. The measured optical density is
correlated with readings on precipitates of known sulfate concentrations. The test results
are presented on the following table:
&
LOR GEOTECHNICAL GROUP, INC.
SOLUBLE SULFATE CONTENT TESTS
Boring
Number
Sample Depth
(feet)
Soil Description
(U.S.G.S.)
Sulfate
Content
(percent by
weight)
B-1 1-4 (CL) Lean Clay with Sand < 0.005
B-4 3-6 (SC) Clayey Sand < 0.005
LOR*(27(&+1,&$/*5283,1&
&
1003/8 70 140
D30
30
0
20
40
50
60
70
80
90
10
100
0.0010.010.1110100
11.1
16 20 30 50640
COBBLES
3
16.7
SILT OR CLAY
18
B-1
B-4
@ 1-4 ft
@ 3-6 ft
4
DATE
%Clay
RV
HYDROMETER
ENCLOSURE C-1
Proposed Apartment Complex
D10
PROJECT NO.33616.1
2/17/20
PROJECT
%Silt%Sand
8 10 14
(CL) Lean Clay with Sand
(CL) Lean Clay with Sand
RV
4.2
7.9
GRADATION CURVES
GRAVEL
D60
P
E
R
C
E
N
T
F
I
N
E
R
B
Y
W
E
I
G
H
T
GRAIN SIZE IN MILLIMETERS
finemediumcoarse
SAND
6
79.1
81.0
200
U.S. SIEVE NUMBERS
fine
B-1
B-4
SE
U.S. SIEVE OPENING IN INCHES
1/2
coarse
4 3 2 1.5 3/4
5
Specimen Identification
Specimen Identification
Cc Cu
D100
LOR Geotechnical Group, Inc.
1
25.40
%Gravel
PL PI
@ 1-4 ft 19.00
16
Soil Classification
3
3
--
@ 3-6 ft
0
10
20
30
40
50
60
0 20 40 60 80 100
CH
MH
LIQUID LIMIT (LL)
B-1 34 16 18 79.1@ 1-4 ft
ATTERBERG LIMITS' RESULTS
CL-ML
Project:Project No.:
Date:
33616.1
2/17/20
Proposed Apartment Complex
ENCLOSURE: C - 2LOR Geotechnical Group, Inc.
(CL) Lean Clay with Sand
ML
CL
Specimen Identification LL PL PI Fines Classification
P
L
A
S
T
I
C
I
T
Y
I
N
D
E
X
APPENDIX D
Seismic Design Spectra
LOR GEOTECHNICAL GROUP, INC.
Project:APN 375-291-14
Project Number:33616.1
Client:C & C Development
Site Lat/Long;33.8070/-117.8575
Controlling Seismic Source:Puente Hills
REFERENCE NOTATION VALUE REFERENCE NOTATION VALUE
Site Class A, B, C, D, E or F D (Site Class D (Measured) only)Fv (Table 11.4-2)[Used for General Spectrum]Fv 1.8
Site Class D - 21.2.2.(ii)Fa 1 Design Maps SMS 1.412
Site Class D - 21.2.2.(ii)Fv 2.5 Design Maps SDS 0.941
0.2*(SD1/SDS)T0 0.127 Design Maps S1 0.501
SD1/SDS TS 0.637 Design Maps FPGA 1.1
Fundamental Period (12.8.2)T Period Design Maps PGA 0.593
Seismic Design Maps or Fig 22-14 TL 8 Equation 11.8-1 PGAM 0.652
2/3*SM1 SD1 0.599 Section 21.5.3 80% of PGAM 0.522
FV*S1 SM1 0.899 Design Maps CR1 0.923
Design Maps Crs 0.926
Cr - At Perods <=0.2, Cr=CRS Cr 0.926
Cr - At Periods >=1.0, Cr=Cr1 Cr 0.923
Cr - At Periods between 0.2 and 1.0 Period Cr
use trendline formula to complete 0.200 0.926
0.300 0.926
0.400 0.925
0.500 0.925
0.600 0.925
0.680 0.924
1.000 0.923
RISK COEFFICIENT
y = -0.0038x + 0.9268
0.9225
0.923
0.9235
0.924
0.9245
0.925
0.9255
0.926
0.9265
0.000 0.200 0.400 0.600 0.800 1.000 1.200
Cr Interpolation 0.2 to 1.0
LOR Geotechnical Group, Inc.
0.005 0.74 0.70 0.76 0.73 0.926 0.679
0.020 0.75 0.70 0.77 0.74 0.926 0.688
0.030 0.78 0.73 0.81 0.77 0.926 0.716
0.040 0.82 0.78 0.85 0.82 0.926 0.758
0.050 0.85 0.83 0.92 0.86 0.926 0.801
0.060 0.93 0.91 0.99 0.94 0.926 0.871
0.080 1.06 1.05 1.12 1.08 0.926 0.998
0.090 1.13 1.12 1.19 1.15 0.926 1.060
0.100 1.19 1.19 1.25 1.21 0.926 1.120
0.120 1.29 1.29 1.38 1.32 0.926 1.220
0.136 1.36 1.36 1.45 1.39 0.926 1.289
0.200 1.51 1.49 1.58 1.53 0.926 1.416
0.300 1.54 1.43 1.54 1.50 0.926 1.392
0.400 1.48 1.33 1.42 1.41 0.925 1.306
0.500 1.45 1.26 1.30 1.34 0.925 1.241
0.600 1.35 1.18 1.20 1.25 0.925 1.157
0.680 1.30 1.13 1.15 1.20 0.924 1.105
1.000 1.04 0.97 0.97 1.00 0.923 0.919
1.200 0.90 0.84 0.83 0.86 0.923 0.794
2.000 0.59 0.57 0.51 0.56 0.923 0.515
3.000 0.40 0.39 0.33 0.38 0.923 0.348
4.000 0.30 0.30 0.24 0.28 0.923 0.260
5.000 0.25 0.27 0.18 0.24 0.923 0.217
B-A - Boore-Atkinson (2008) NGA USGS 2008 MRC 0.679
C-B - Campbell-Bozorgnia (2008) NGA USGS 2008 MRC
C-Y - Chiou-Youngs (2007) NGA USGS 2008 MRC
Project No:33616.1
Probabilistic PGA:
PROBABILISTIC SPECTRA
2% in 50 year Exceedence
B - A C - B C - Y Mean Risk Coefficient
(CR)
Probabilistic
MCEPeriod
LOR Geotechnical Group, Inc.
33616.1Project No:
0.00
0.50
1.00
1.50
2.00
0.000 1.000 2.000 3.000 4.000 5.000 Acceleration (g) Period (seconds)
PROBABILISTIC MCER
SPECTRAL RESPONSE ACCELERATIONS
Boore-Atkinson (2008) NGA USGS 2008 MRC
Campbell - Bozorgnia (2008) NGA USGS 2008 MRC
Chiou-Youngs (2007) NGA USGS 2008 MRC
Probabilistic MCE
Analysis Information
Spectral Response @ 5 % Damping
with Maximum Rotated
Component.
Probability of Exceedence:
2% in 50 years
LOR Geotechnical Group, Inc.
Puente Hills
0.005 0.646 0.623 0.646
0.020 0.655 0.692 0.692
0.030 0.680 0.739 0.739
0.040 0.714 0.785 0.785
0.050 0.748 0.831 0.831
0.060 0.803 0.877 0.877
0.080 0.915 0.970 0.970
0.090 0.974 1.016 1.016
0.100 1.032 1.062 1.062
0.120 1.129 1.154 1.154
0.136 1.196 1.228 1.228
0.200 1.358 1.500 1.500
0.300 1.392 1.500 1.500
0.400 1.376 1.500 1.500
0.500 1.334 1.500 1.500
0.600 1.241 1.500 1.500
0.680 1.179 1.500 1.500
1.000 1.030 1.500 1.500
1.200 0.941 1.250 1.250
2.000 0.678 0.750 0.750
3.000 0.499 0.500 0.500
4.000 0.381 0.375 0.381
5.000 0.309 0.300 0.309
Deterministic PGA:0.646
Boore - Atkinson (2008) NGA USGS 2008 MRC
Campbell - Bozorgnia (2008) NGA USGS 2008 MRC
Chiou - Youngs (2007) NGA USGS 2008 MRC Project No:33616.1
*Attenuation Equations
DETERMINISTIC SPECTRUM AND LOWER LIMIT
Largest Amplitudes of Ground Motions Considering All Sources Calculated using Weighted Mean of Attenuation Equations*.
DETERMINISTIC
LOWER LIMIT
DETERMINISTIC
MCE 84 FRACTILE
DETERMINISTIC
(RAW)Period
Controlling Source:
LOR Geotechnical Group, Inc.
33616.1Project No:
0.00
0.50
1.00
1.50
2.00
0.000 1.000 2.000 3.000 4.000 5.000 Acceleration (g) Period (seconds)
DETERMINISTIC MCER
SPECTRAL RESPONSE ACCELERATIONS Deterministic Lower Limit
Deterministic (Raw)
Deterministic MCE
LOR Geotechnical Group, Inc.
0.005 0.679 0.646 0.646 0.430 0.005 0.399 0.319
0.020 0.688 0.692 0.688 0.459 0.010 0.421 0.337
0.030 0.716 0.739 0.716 0.478 0.030 0.509 0.408
0.040 0.758 0.785 0.758 0.505 0.040 0.554 0.443
0.050 0.801 0.831 0.801 0.534 0.050 0.598 0.478
0.060 0.871 0.877 0.871 0.581 0.060 0.642 0.514
0.080 0.998 0.970 0.970 0.646 0.080 0.731 0.585
0.090 1.060 1.016 1.016 0.677 0.090 0.775 0.620
0.100 1.120 1.062 1.062 0.708 0.100 0.820 0.656
0.120 1.220 1.154 1.154 0.770 0.110 0.864 0.691
0.136 1.289 1.228 1.228 0.819 0.120 0.908 0.727
0.200 1.416 1.500 1.416 0.944 0.136 0.941 0.753
0.300 1.392 1.500 1.392 0.928 0.150 0.941 0.753
0.400 1.306 1.500 1.306 0.870 0.160 0.941 0.753
0.500 1.241 1.500 1.241 0.827 0.170 0.941 0.753
0.600 1.157 1.500 1.157 0.771 0.180 0.941 0.753
0.680 1.105 1.500 1.105 0.737 0.190 0.941 0.753
1.000 0.919 1.500 0.919 0.613 0.200 0.941 0.753
1.200 0.794 1.250 0.794 0.529 0.300 0.941 0.753
2.000 0.515 0.750 0.515 0.343 0.400 0.941 0.753
3.000 0.348 0.500 0.348 0.232 0.500 0.941 0.753
4.000 0.260 0.381 0.260 0.174 0.600 0.941 0.753
5.000 0.217 0.309 0.217 0.145 0.640 0.936 0.749
0.680 0.881 0.705
0.850 0.705 0.564
Calculated Design 0.900 0.666 0.533
Value Value 0.950 0.631 0.505
SDS:0.850 0.850 1.000 0.599 0.479
SD1:0.724 0.724 1.200 0.499 0.400
SMS:1.274 1.274 2.000 0.300 0.240
SM1:1.086 1.086 3.000 0.200 0.160
4.000 0.150 0.120
Site Specfic MCEg:0.646 5.000 0.120 0.096
Site Class:D - measured
Project No:33616.1
ASCE 7-16: Section 21.4
SITE SPECIFIC SPECTRA
Probabilistic
MCE
Deterministic
MCEPeriod Site-Specific
MCE Period 80% General
Response Spectrum
ASCE 7 SECTION 11.4.6
General SpectrumDesign Response
Spectrum (Sa)
LOR Geotechnical Group, Inc.
33616.1Project No:
0.00
0.50
1.00
1.50
2.00
0.000 1.000 2.000 3.000 4.000 5.000 Acceleration (g) Period (seconds)
SPECTRAL RESPONSE ACCELERATIONS Probabilistic MCE
Deterministic MCE
Site-Specific MCE
Design Response Spectrum
ASCE 7 Section 11.4.6 General Spectrum
80% General Response Spectrum
LOR Geotechnical Group, Inc.
Appendix F:
Watershed Maps
"Proj Site
JSoil Group Map
ORANGE
COUN
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YORANGE
COUN
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YRI
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ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORANGE COUNTYORANGE COUNTYLOS ANGELES COUNTYLOS ANGELES COUNTY1.05
0.7
10.950.90.850.80.750.70.650.
9
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0.70.90.9
0.
7
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P:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-1_RainfallZones_20110215.mxdFIGUREJOBTITLESCALE1" = 1.8 milesDESIGNEDDRAWINGCHECKEDBMP04/22/10DATEJOB NO.9526-ETHTHORANGE COUNTYTECHNICAL GUIDANCEDOCUMENTORANGE CO.CARAINFALL ZONESSUBJECT TO FURTHER REVISION
03.67.21.8
Miles
06123
Kilometers
LEGEND
Orange County Precipitation Stations
24 Hour, 85th Percentile Rainfall (Inches)
24 Hour, 85th Percentile Rainfall (Inches) - Extrapolated
City Boundaries
Rainfall Zones
Design Capture Storm Depth (inches)
0.65"
0.7
0.75
0.80
0.85
0.90
0.95
1.00
1.10"
Note: Events defined as 24-hour periods (calendar days) with greater
than 0.1 inches of rainfall.
For areas outside of available data coverage, professional judgment
shall be applied.
XVI-1
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ORANGE COUNTYORANGE COUNTY
LOS ANGELES COUNTYLOS ANGELES COUNTY
ORANGE COUNTYORANGE COUNTYLOS ANGELES COUNTYLOS ANGELES COUNTYP:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-2e_DepthToGroundwaterLt5ft_20110215.mxdFIGURE
XVI-2eJOBTITLESCALE1" = 1.25 milesDESIGNEDDRAWINGCHECKEDBMP02/09/11DATEJOB NO.9526-ETHTHORANGE COUNTYINFILTRATION STUDYORANGE CO.CANORTH ORANGE COUNTYMAPPED SHALLOW GROUNDWATERSUBJECT TO FURTHER REVISION
Note: Data are not available for South Orange County at this time.
Source:
Sprotte, Fuller and Greenwood, 1980.
California Division of Mines and Geology;
California Geological Survey
!I
02.551.25
Miles
0482
Kilometers
LEGEND
City Boundaries
OCWD Groundwater Basin Protection Boundary
Depth To Groundwater
<= 5'
5-10'
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LOS ANGELES COUNTYLOS ANGELES COUNTY
ORANGE COUNTYORANGE COUNTYLOS ANGELES COUNTYLOS ANGELES COUNTYP:\9526E\6-GIS\Mxds\Reports\InfiltrationFeasability_20110215\9526E_FigureXVI-2f_NorthOCGroundwaterProtectionAreasStreetMap_20110215.mxdFIGURE
XVI-2fJOBTITLESCALE1" = 1.25 milesDESIGNEDDRAWINGCHECKEDBMP04/22/10DATEJOB NO.9526-ETHTHORANGE COUNTYINFILTRATION STUDYORANGE CO.CANORTH ORANGE COUNTYGROUNDWATER PROTECTIONAREASSUBJECT TO FURTHER REVISION
Note: Individual contamination sites are not plotted.
See State Water Resources Control Board Geotracker database
(http://geotracker.waterboards.ca.gov),
Department of Toxic Substance Control Envirostor database
(http://www.envirostor.dtsc.ca.gov) and other applicable sources
for current listing of active contaminated sites.
Groundwater basin and plume protection boundaries for
South Orange County are not shown on this exhibit
at this time
!I
02.551.25
Miles
0482
Kilometers
LEGEND
City Boundaries
OCWD Groundwater Basin Protection Boundary
Plume Protection Boundaries
North Basin Groundwater Protection Project
South Basin Groundwater Protection Project
El Toro Marine Base
Tustin Marine Air Base
Approximate Selenium Contamination Area
P:\9526E\6-GIS\Mxds\SuceptabilityMaps_20100505\9526E_SantaAnaRiverSusceptibility_20100430.mxdCleveland
National Forest
San Bernardino
County
Riverside County
South Orange
County
Newport Bay
Watershed
Stabilized by
Grade Control
Structure
San Gabriel-Coyote Creek
Watershed
Anaheim Bay-
Huntington Harbor
Watershed
Peters
Canyon
Reservoir
Olive
Hills
Kraemer
Basin
Carbon
Canyon
Walnut
Canyon
Reservoir
Irvine
Lake
Anaheim
Lake
Warner
Basin
Miller
Retarding
Basin
Bartlett
Retarding
Basin
Fletcher
Retarding
Basin
SOUTHPARK
PUMP
STATION
Villa
Park Dam
Yorba Linda
Reservoir
Sources: Esri, DeLorme, NAVTEQ, TomTom, USGS, Intermap, iPC, NRCAN, Esri Japan, METI, Esri China (Hong Kong), Esri (Thailand)
FIGURE
3JOBTITLESCALE1" = 12000'DESIGNEDDRAWINGCHECKEDBMP04/30/10DATEJOB NO.9526-ETHTHORANGE COUNTYWATERSHEDMASTER PLANNINGORANGE CO.CASUSCEPTIBILITY ANALYISSANTA ANA RIVER0 12,000 24,000
Feet
Susceptibility
Potential Areas of Erosion, Habitat, &
Physical Structure Susceptibility
Channel Type
Earth (Unstable)
Earth (Stabilized)
Stabilized
Tidel Influence
<= Mean High Water Line (4.28')
Water Body
Basin
Dam
Lake
Reservoir
Forest Areas
Cleveland National Forest
Federal Lands
Amarus Salt Marsh
Sources: Esri, DeLorme, NAVTEQ,
TomTom, USGS, Intermap, iPC,
NRCAN, Esri Japan, METI, Esri
China (Hong Kong), Esri (Thailand)
PRELIMINARY MAP – SUBJECT TO FURTHER REVISION
686&(37,%,/,7<0$383'$7( '(&