HomeMy WebLinkAbout20200908_Geotechnical Investigation_8-21-2020601 Glenneyre St• Suite F • Laguna Beach• CA 92651
(949) 494-2122 • FAX {949) 497-0270
August 21, 2020
Kevin and Vicki Coop
c/o Brion Jeannette Architecture
470 Old Newport Blvd.
Newport Beach. California
Attention:
Subject:
Ms. Amy Creager, Architect
Preliminary Geotechnical Investigation
Proposed New Single~Family Residence
408 Via Lido Nord, Lido Island
Newpott Beach, California
INTRODUCTION
Project No: 72514-00
Repo1t No: 20~8758
This report presents findlngs and conclusions of a preliminary geotechnical investigation
undertaken to relate onsite and certain regional geotechnical conditions to the construction of a
new single-family residence on the subject property. Analyses for this investigation arc based
upon a review of conceptual architectural plans for the property prepared by Brion Jeanette
Architecture and the site topographic plan prepared by Forkert Engineering and Surveying.
The conclusions and recommendations of this report are considered preliminary due to the
absence of finalized foundation and grading plans, the formulation of which are partially
dependent upon the recommendations presented herein.
Scope of Investigation
The investigation included the following:
I. Analysis of pertinent reports, maps. aerial photographs, historic laboratory and boring
data, and published literature pertaining to the site and nearby areas, as well as project
plans, in order to relate geotechnical conditions to proposed construction.
2. Advance one cone penetration test {CPT) to approximately l i .5 feet in order to further
evaluate the geotechnical conditions and to perform a llquefaction analysts.
3. Analyses of data and the preparation of this geotechnical report presenting conclusions
and recommendations for site development in accordance \.Vith the 2019 California
Building Code and the City of Newport Beach Building Code Policies. This report is
st1itable for use by your design professionals, contractors, and submittal to the City of
Newport Beach.
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Accompanying Illustrations and Appendices
Figure I
Figure 2
Figure 3
Appendix A
Appendix B
Appendix C
Appendix D -
Appendix E
Plate I
Site Description
USGS Geologic Location Map
CDMG Geologic Hazards Location Map
Typical Retaining Wall Subdrain Detail
References
Cone Penetration Test Boring Log
Liquefaction Analysis
Standard Grading Specifications
Utility Trench Backfill Guidelines
Geotechnical Plot Plan and Sections A-A ' and B-B'
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The generally rectangular-shaped bayfront property fronts 35.0± feet along Via Lido Nord and
extends southwesterly 90.0± feet to the rear property boundary along 35.0± feet of Newport
Bay boardwalk. The lot is generally flat with a 2% gradient sloping from a high point in its
southwest corner of 12.19 feet (NA VD88) to a low point of I 0.36 feet in the northeast corner
against the boardwalk. The northerly property line along Newport Bay is bordered by an
approximately 4± feet tall retaining wall supporting a grade differential of approximately 1.8±
feet. Plans provided to our office by Forkert Engineering indicate that the Newport Bay
bulkhead is approximately 65 ' feet northerly of the existing retaining wall and is buried
underneath bay sand deposits.
The existing 0.07-acre property at 408 Via Lido Nord is improved with a two-story wood-
framed structure built in the I 950's. The residence is separated from neighboring residences
to the east and west by conventional site walls.
Proposed Development
Based on a review of conceptual plans prepared by Brion Jeannette Architecture, proposed site
development generally consists of the demo I it ion of the existing residence to faci I itate
construction of a new two-story, single-family residence of wood and steel framing and
exterior hardscaping. The new residence is anticipated to be supported on a stiffened mat
foundation system constructed in new engineered fill as recommended herein. The proposed
residence first floor elevation will be located approximately 6 to 24 inches above current
grades. Proposed minor grade changes at the rear of the residence will require small amounts
of retaining wall backfill.
GEOTECHNICAL CONDITIONS
Geologic Setting
The property is located on Lido Isle adjacent to Newport Bay as depicted on the USGS
Geologic Index Map, Figure I. It is located 0.6± miles northerly of the Pacific shoreline,
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approximately 0.7± miles northeasterly of the Newport pier and is 0.2± miles southwesterly of
a former sea bluff on the inland side of Lido Isle. Review of old topographic maps indicates
that prior to dredging ofNewpmt Bay, the site location was a low lying, likely intertidal area
adjacent to a shallow channel of the natural bay. The site is underlain at a depth in excess of
50 feet by an accumulation of intertidal bay and beach deposits and subsequent dredge fill
placed during land reclamation. A younger generation of fill from construction of the existing
roads and residence may underlie portions of the property at the surface.
Earth Materials
The bedrock underlying the property at significant depth is assigned to strata of the Monterey
Formation on the basis of regional mapping. Where exposed offsite on local bluffs, strata of
the Monterrey consists of weakly cemented sequences of siltstone and claystone forming a
laminated to thinly bedded shale. This material was not observed during our drilling and is
not anticipated to be encountered during construction at the site.
Based upon nearby studies, review of regional geologic mapping the site is underlain at depth
by 6± inches of intertidal bay deposits, which are successively overlain by dredge fill.
Intertidal bay deposits generally consist of very dark gray, variably silty and clayey, saturated,
medium dense, fine to medium quartzo-feldspathic sand with some organic matter. Dredge
fill overlies the intertidal bay/beach deposits and consists of 7± feet of tan light-brown, moist
to very moist, loose to medium dense, fine to medium grained quartzo-feldspathic sand with
many shell fragments.
Following demolition, the upper 3± feet of fill below existing grade is considered unsuitable in
its present form to support new structural loads but may be removed and recompacted to
produce acceptable engineered fill. Onsite materials are non-expansive on the basis of visual
classification, and laboratory testing from neighboring sites indicates negligible soluble sulfate
concentrations.
Groundwater
Exploratory testing on site and on nearby properties encountered groundwater at depth of 7.0±
feet below ground surface ( elevation 5± feet (NA VD88)). This groundwater level is
anticipated to experience some fluctuation in response to the tidal cycle and/or during periods
of heavy rain. The design groundwater level is recommended to be equal to the maximum
predicted tide elevation during heavy rainfall, which is at an elevation of 8 ± feet (NA VD88).
Surface Runoff and Street Flooding
Proposed development will modify and may increase post-development surficial discharge,
which must be controlled by appropriate civil engineering design. Localized street flooding
associated with heavy rains and high tides has been a recurrent phenomenon in the Newport
Bay communities. The potential for street flooding affecting proposed development should be
evaluated by the project civil engineer.
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Seismic Considerations
Published Studies
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One of the principals of seismic analyses and prediction is the premise that earthquakes are
more likely to occur on geologically younger faults, and less likely to occur on older faults.
For many years studies have described faults with Holocene movement (within the last 11,700
years) as "Active", and faults with documented Pleistocene movement (within the last 1.6
million years) and with undetermined Holocene movement as "Potentially Active".
Informally, many studies have described faults documented to have no Holocene movement as
"Inactive". Recent geologic and seismic publications are attempting to clarify the
nomenclature describing faults to more accurately represent the potential affects from
earthquakes.
Reports by the California Division of Mines and Geology indicate faults with documented
Holocene or Historic (within the last 200 years) movement should be considered Active.
However, Potentially Active faults are more appropriately characterized in terms of the last
period of documented movement. The Fault Activity Map of California (Jennings, C. W.;
20 I 0) defines three categories for onshore Potentially Active faults. The categories are
associated with the time of the last displacement evidenced on a given fault and are
summarized in Table I.
Table 1, Definitions of Fault Activity in California
Activity Category Recency of Movement
Active Historic Within the last 200 years
Holocene Within the last 11,700 years
Late Quaternary Within the last 700,000 years
Potentially Active Quaternary Within the last 1.6 million years
Pre-Quaternary Before the last 1.6 million years
It is important to note these categories embrace all Pre-Holocene faults as Potentially Active,
and provide no methodology to designate a given fault as "Inactive". Although the likelihood
of an earthquake or movement to occur on a given fault significantly decreases with inactivity
over geologic time, the potential for such events to occur on any fault cannot be eliminated
within the current level of understanding.
Local and Regional Faults
The closest published active fault to the site is the offshore extension of the Newport-
Inglewood Fault Zone, approximately 1.0 miles south-southwest, (COS, 2005). Other active
faults in the vicinity of the site include the San Joaquin Hills, approximately 5 .8 miles
northeast, the Palos Verdes Fault, approximately I 2.6 miles to the west-northwest; the
Coronado Bank Fault, approximately 23.6 miles southwest; the Elsinore Fault, approximately
24.3 miles to the east, and the San Andreas Fault, approximately 47.8 miles to the northeast.
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The California Geological Survey updated the Fault Parameters and Earthquake Catalog for
the probabilistic Seismic Hazards Maps in 2002. This update included the addition of the San
Joaquin Hills blind thrust fault indicated above, theorized to exist from Newport Beach to
Dana Point, and ramping up inland to the Irvine area, and essentially underlying the site.
Earthquakes of Magnitude 7.0+ are presently postulated for this structure. With the Newport-
Inglewood fault's location at approximately 1.1 miles distant, and a calculated possible
magnitude 7.45 event, it is calculated as the most significant seismic source to affect the
subject site.
Historic Ground Motion Analyses
The USGS earthquake catalog indicates that the maximum historic site acceleration from 1800
to 2020 was approximately 0.4g and occurred during the magnitude 6.3 Long Beach
Earthquake 3.6 miles from the site on March 11, 1933.
It is noted that the estimation of historic peak ground acceleration presented above is provided
for the interest of the client and is required by local (City or County) review agencies. The
value derived is not directly utilized in structural design of residential structures. Seismic
parameters for use by the structural engineer in accordance with 2019 California Building
Code in design of the proposed structure(s) are presented in the recommendations portion of
this report.
Site Classification for Seismic Design
For the purposes of determining seismic design parameters provided in the Recommendations
portion of this report pertaining to the new structures, the upper one hundred feet of soil
underlying the subject site has been classified in accordance with Section 1613.2.2 of the 2019
CBC and Section 20.1 of ASCE 7-16. Although the soils underlying the site are liquefiable
and defined as site class F per the 2019 CBC, requiring a site-response analysis, proposed new
structures are anticipated to have fundamental periods of vibration less than 0.5 seconds (to be
verified by the structural engineer). As such, Section 20.3.1 in ASCE 7-16 provides an
exception that indicates such liquefiable sites may be classified in accordance with Tables
11 .4-1 and 11.4-2 without performing a site-specific evaluation.
Given the exception and the results of our onsite and nearby field investigations, which
indicate the site is predominantly underlain by dredge fill and sedimentary deposits with
average N-values between 15 and 50, seismic design criteria may be calculated using a site
classification of D. However, the Site Class remains F.
Appraisal of Liquefaction Potential
Review of the Seismic Hazard Zones Map for the Newport Beach Quadrangle (California
Division of Mines & Geology, 1998) identifies the site and all of the Newport/Balboa
peninsula and harbor within a zone of required investigation for liquefaction. In accordance
with City of Newport Beach Building Code Policies CBC-1803.5 and 1803.5.11-12, our office
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has performed an analysis for liquefaction potential based on the cone penetration test data
collected during our onsite investigation.
Based on the results of our analysis presented in Appendix C, which indicates liquefaction
settlement within the zone IO feet below the proposed foundation level is less than I-inch, a
stiffened foundation system or mat slab designed in accordance with the City's "Shallow
Mitigation Methods" is recommended.
Tsunami Appraisal
No specific tsunami analysis has been undertaken in this investigation. However, the
"Evaluation of Tsunami Risk to Southern California Coastal Cities" (Legg et al, 2003)
provides a framework for understanding the impact of locally seismic and/or landslide
generated tsunamis. Based on the results of this work, typical maximum run-up heights were
estimated to vary from I to 2 meters in the Newpo1t Beach area. Because of unknown
bathymetry on wavefield interactions and irregular coastal configurations, actual maximum
run-up heights could range from 2 to 4 meters, or more.
Secondary Seismic Hazards
Review of the Seismic Hazards Zones Map (California Division of Mines and Geology, 1998)
for the Newpo1t Beach Quadrangle, Figure 2, indicates this lot is not located within a "zone of
required investigation" for earthquake induced landslides, but is located in a liquefaction
hazard zone. Please refer to the Appraisal of Liquefaction Potential above for more
information.
Other secondary seismic hazards can include deep rupture, shallow ground cracking, and
tsunami inundation. With the absence of active faulting onsite, the potential for deep fault
rupture is not present. The potential for shallow ground cracking to occur during an
earthquake is a possibility at any site but does not pose a significant hazard to site
development. Regarding tsunami inundation, please refer to the appropriate section above for
more information.
CONCLUSIONS
I. The proposed development at the subject site is considered geotechnically feasible
providing recommendations herein are integrated into design, construction, and long-
term maintenance. Proposed construction should not affect or be affected by adjacent
properties providing appropriate construction methods and care is utilized during
construction.
2. The property is underlain at a significant depth by bedrock strata of the Monterey
Formation, which are successively overlain by tidal bay/beach deposits, and 7.0± feet
of dredge fill.
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3. The upper 3± feet of existing dredge fill is considered unsuitable in its present form to
support new foundations but may be removed and recompacted to produce acceptable
engineered fill, pending observation by a licensed geologist.
4. Granular onsite soils are non-expansive and are expected to have a negligible soil
soluble sulfate level, and a severe potential for corrosion of buried metal based on
nearby laboratory testing. However, as placed concrete is in a marine environment, a
moderate sulfate exposure may be used for design purposes. The concrete mix should
be designed by a concrete expert in consideration of structural requirements. The
appropriate exposure should be evaluated by the architect and/or structural engineer.
5. No active faults are known to transect the site and therefore the site is not expected to
be adversely affected by surface rupturing. It will, however, be affected by ground
motions from eaithquakes during the design life of the residence.
6. Liquefaction analysis performed in accordance with City Building Code Policies CBC-
1803 .5 and 1803.5.11-12 indicates seismic settlement in the zone IO feet below the
proposed foundation level is less than I-inch. Therefore, a mat slab or stiffened
foundation system designed in accordance with the City's "Shallow Mitigation
Methods" is recommended.
7. Groundwater was recorded at a depth of 7± feet below ground surface. Groundwater
will fluctuate based on tidal conditions and other factors, and likely will be a design
and construction constraint depending on the depth of improvements and excavations.
The design groundwater level is recommended to be equal to the maximum predicted
tide elevation during heavy rainfall and storm surge runup, which is considered to be at
an elevation of 8± feet (NA VD88).
8. The potential for street flooding to affecting the residence during its lifetime is
deferred to the project civil engineer.
9. Surface discharge onto or off the site should be appropriately controlled with proper
engineering design and site grading and are deferred to the project civil engineer.
I 0. The residence should be founded in competent recompacted engineered backfill
utilizing a mat slab or stiffened foundation system.
RECOMMENDATIONS
Site Preparation and Grading
I. General
Grading is anticipated to consist of remedial over-excavation and minor export of soils
to construct proposed building pad and foundation subgrades. Grading should be
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performed in accordance with the recommendations herein and the Standard Grading
Specifications in Appendix D. Processing, over-excavation and re-compaction should
be observed, tested and approved in writing by a representative of this firm.
2. Remedial Grading and Subgrade Preparation
Remedial grading is recommended to include removal and re-compaction of existing
loose dredge fill to a depth of at least 3 feet below existing site grades. Locally deeper
removals may be required pending field review by the geologist.
As groundwater may be a construction nuisance during high tide levels; saturated
conditions may be encountered during over-excavation grading. In this instance,
subgrade stabilization, such as the placement of geotextile filter fabric, crushed rock,
and another layer of filter fabric should be anticipated prior to placement of backfill.
Typically, a crushed rock layer of at least I foot is adequate.
3. Removal of Existing Improvements
Existing vegetation, organic materials and/or construction and demolition debris
should be removed and disposed of offsite.
4. Compaction Standard
Onsite soil materials are anticipated to be suitable for re-use as compacted fill provided
they are free of rubble and debris. Materials should be placed at 120 percent of
optimum moisture content and compacted under the observation and testing of the soil
engineer to at least 90 percent of the maximum dry density as evaluated by ASTM D
1557.
5. Temporary Construction Slopes
Temporary slopes exposing onsite materials should be cut in accordance with
Cal/OSHA Regulations. It is anticipated that the onsite soils may be classified as Type
C soil, and temporary cuts of 1.5: 1 (horizontal: vertical) may be appropriate; however,
the material exposed in temporary excavations should be evaluated by the contractor
during construction.
The safety of temporary construction slopes is deferred to the general contractor, who
should implement the safety practices as defined in Section 1541, Subchapter 4, of
Cal/OSHA T8 Regulations (2006).
Shoring should be anticipated where space limitations preclude temporary slope
layback, or in any location where onsite personnel may be in close proximity to open
excavations. Shoring also should be anticipated where wet materials exist.
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Foundation Design Parameters
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Due to the potential for liquefaction at the site, we recommend that a stiffened foundation or
mat slab be used for the proposed structure in accordance with the City of Newport Beach
Building Code Policy No. CBC-1803.5.11-12. Such a foundation system should be founded
on properly compacted fill derived from onsite materials.
I. Bearing Capacity and Settlement
The allowable bearing capacity for a mat slab placed on approved recompacted fill with
a thickness of 12 inches or more is 2000 pounds per square foot. Foundation settlement
from structural loading is estimated to be ¾ inch total and ½ inch differential over a
distance of 20 feet. Foundation settlement should occur mostly during construction.
2. Lateral Loads
Lateral loads may be resisted by passive pressure forces and friction acting on the
bottom of foundations. Passive pressure may be computed from an equivalent fluid
density of 150 pounds per cubic foot above the groundwater table, not to exceed 1,500
pounds per square foot. A coefficient of friction of 0.25 may be used in computing the
frictional resistance. These values may be combined without reduction.
3. Reinforcement
Foundations and slabs should be reinforced in conformance with the requirements of the
structural engineer. From a geotechnical viewpoint, a minimum of two No. 5 bars
should be incorporated at the top and bottom of continuous footings in order to reduce
the potential for cracking during seismic shaking or as a result of subsurface
imperfections.
Structural Design of Retaining Walls
I . Lateral Loads
Minor retaining walls to a maximum retained height of under two feet are proposed.
Active pressure forces acting on un-surcharged retaining walls above the groundwater
table which are backfilled with level, free draining granular material may be computed
based on an equivalent fluid pressure of 35 pounds per cubic foot. Structural surcharges
from adjacent structures or improvements, if applicable, should also be considered in
retaining wall design.
The site is classified as being in Seismic Design Category D (Type II occupancy, SDs ::_
0.5g, SDI::_ 0.2g). Seismic design of retaining walls 6 feet or higher may be based on
the Mononobe-Okabe method, as updated by Atik and Sitar (20 I 0), using an additional
dynamic load of 32 pounds per cubic foot equivalent fluid pressure, acting at 1/3 H
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above the base of the wall. Final design requirements should be determined by the
structural engineer.
Retaining Wall Foundations
Bearing capacity and lateral resistance may be computed using the parameters presented
in the foundation sections above.
3. Subdrains
The drainage scheme depicted on Figure 3, or an approved alternative should be used to
reduce the potential for seepage forces behind retaining walls.
4. Wall Excavations
Please refer to the Temporary Construction Slopes section above.
Monitoring
Complete documentation of the pre-and post-construction conditions of adjacent
improvements should be undertaken. In addition, monitoring of ground movement and
construction vibrations should be made as an integral part of the construction. Such
documentation should include:
I. A sufficient number of photographs to establish the existing condition of nearby
structures.
2. Establishment of a sufficient number of ground elevation control stations so that
potential subsidence or heave associated with grading and lateral movement can be
detected. Monitoring of such points should be accomplished during all grading,
shoring (if any) and excavation work, and continued until retaining walls are backfilled
or site grading is complete.
3. Ground vibration monitoring during construction to capture peak particle velocities of
drilling, tracking, and excavation activities is recommended. Vibration monitors
should be Sigicom model C-22 tri-axial geophones or equivalent.
Hardscape Design and Construction
Hardscape improvements may utilize conventional foundations embedded in recompacted fill
designed in accordance with the foundation recommendations presented above. Foundations
should have a design depth of 18 inches or more.
Concrete flatwork should be divided into as nearly square panels as possible. Joints should be
provided at maximum 6 feet intervals to give articulation to the concrete panels. Landscaping
and planters adjacent to concrete flatwork should be designed in such a manner as to direct
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drainage away from concrete areas to approved outlets. Planters located adjacent to principal
foundation elements should be sealed and drained.
Flatwork elements should be a minimum 5 inches thick (actual} and reinforced with No. 4 bars
16 inches on center both ways.
Seismic Design
Based on the geotechnical data and site parameters, the following is provided by the USGS
(ASCE 7-16) to satisfy the 2019 CBC design criteria:
Table 2, Site and Seismic Design Criteria
for 2019 CBC
Design Recommended
Parameters Values
Site Class F
Site Longitude (degrees) -117.9191
Site Latitude (degrees) 33.6144
Ss (g) B 1.384
SI (g) B 0.493
SMs (g) D 1.661
SM! (g) D 1.232
SDs (g) D 1.108
SDI (g) D 0.822
Fa 1.2
Fv 2.5
Seismic Design Category D
This evaluation assumes the jzmdamental period of vibration of proposed
structures does not exceed 0.5 second. The structural consultant should
review the above parameters and the California Budding code to evaluate
the seis1nic design.
Finished Grade and Surface Drainage
Finished grades should be designed and constructed so that no water ponds in the vicinity of
footings. Drainage design in accordance with the 2019 California Building Code, Section
1804.4 is recommended. Roofs should be guttered and discharge conducted away from the
house in a non-erosive manner as specified by the project civil engineer or landscape architect.
Proper interception and disposal of all onsite surface discharge is presumed to be a matter of
civil engineering or landscape architectural design.
Concrete
Soil soluble sulfate testing indicates negligible sulfate content. On-site concrete may be
exposed to seawater. It is recommended that a concrete expert be retained to design an
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appropriate concrete mix to address the structural and exposure requirements. In lieu of
retaining a concrete expe11, it is recommended that the 2019 California Building Code, Section
1904.1 be utilized, which refers to AC! 318, Table 4.3. The appropriate exposure should be
evaluated by the architect and/or structural engineer.
Foundation Plan Review
In order to help assure conformance with recommendations of this report and as a condition of
the use of this report, the undersigned should review final foundation plans and specifications
prior to submission of such to the building official for issuance of permits. Such review is to
be performed only for the limited purpose of checking for conformance with the design
concept and the information provided herein. This review shall not include review of the
accuracy or completeness of details, such as quantities, dimensions, weights or gauges,
fabrication processes, construction means or methods, coordination of the work with other
trades or construction safety precautions, all of which are the sole responsibility of the
Contractor. Geofirm's review shall be conducted with reasonable promptness while allowing
sufficient time in our judgment to permit adequate review. Review of a specific item shall not
indicate that Geofirm has reviewed the entire system of which the item is a component.
Geofirm shall not be responsible for any deviation from the Construction Documents not
brought to our attention in writing by the Contractor. Geofirm shall not be required to review
partial submissions or those for which submissions of correlated items have not been received.
Utility Trench Backfill
Utility trench backfill should be placed in accordance with Appendix E, Utility Trench
Backfill Guidelines. It is the owners and contractors responsibility to inform subcontractors of
these requirements and to notify Geofinn when backfill placement is to begin.
Jobsite Safety
Neither the professional activities ofGeofirm, nor the presence ofGeofirm's employees and
subconsultants at a construction/project site, shall relieve the General Contractor of its
obligations, duties and responsibilities including, but not limited to, construction means,
methods, sequence, techniques or procedures necessary for performing, superintending and
coordination the work in accordance with the contract documents and any health or safety
precautions required by any regulatory agencies. Geofirm and its personnel have no authority
to exercise any control over any construction contractor or its employees in connection with
their work or any health or safety programs or procedures. The General Contractor shall be
solely responsible for jobsite safety.
Pre-Grade Meeting
A pre-job conference should be held with representative of the owner, contractor, architect,
civil engineer, soils engineer, engineering geologist, and building official prior to
commencement of construction to clarify any questions relating to the intent of these
recommendations or additional recommendations.
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Observation and Testing
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The 2019 California Building Code, Section 1705.6 requires geotechnical observation and
testing during construction to verify proper removal of unsuitable materials, that foundation
excavations are clean and founded in competent material, to test for proper moisture content
and proper degree of compaction of fill, to test and observe placement of wall and trench
backfill materials, and to confirm design assumptions. It is noted that the CBC requires
continuous verification and testing during placement of fill, pile driving, and pier/caisson
drilling.
A Geofirm representative shall visit the site at intervals appropriate to the stage of
construction, as notified by the Contractor, in order to observe the progress and quality of the
work completed by the Contractor. Such visits and observation are not intended to be an
exhaustive check or a detailed inspection of the Contractor's work but rather are to allow
Geofirm, as an experienced professional, to become generally familiar with the work in
progress and to determine, in general, if the work is proceeding in accordance with the
recommendations of this repmt.
Geofirm shall not supervise, direct, or have control over the Contractor's work nor have any
responsibility for the construction means, methods, techniques, sequences, or procedures
selected by the Contractor nor the Contractor's safety precautions or programs in connection
with the work. These rights and responsibilities are solely those of the Contractor.
Geo firm shall not be responsible for any acts or omission of the Contractor, subcontractor, any
entity performing any portion of the work, or any agents or employees of any of them.
Geofirm does not guarantee the performance of the Contractor and shall not be responsible for
the Contractor's failure to perform its work in accordance with the Contractor documents or
any applicable law, codes, rules or regulations.
These observations are beyond the scope of this investigation and budget and are conducted
on a time and material basis. The responsibility for timely notification of the start of
construction and ongoing geotechnically involved phases of construction is that of the owner
and his contractor. Typically, at least 24 hours' notice is required.
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LIMITATIONS
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This investigation has been conducted in accordance with generally accepted practice in the
engineering geologic and soils engineering field. No further warranty is offered or implied.
Conclusions and recommendations presented are based on subsurface conditions encountered
and are not meant to imply a control of nature. As site geotechnical conditions may alter with
time, the recommendations presented herein are considered valid for a time period of one year
from the report date. The recommendations are also specific to the current proposed
development. Changes in proposed land use or development may require supplemental
investigation or recommendations. Also, independent use of this report in any form cannot be
approved unless specific written verification of the applicability of the recommendations is
obtained from this firm.
Thank you for this opportunity to be of service. If you have any questions, please contact this
office.
Respectfully submitted,
~~~-~;~ GEOFIRM l 7·· '?),,,_~ ,,----~<o '\~ .,,,, / l0% "-.G''
.,, , / • i t;; \W ~. ..., \ /J . <. ,/ '.. ~"V-'7 / Q' KEVIN A TRIGG \ ;.,. -,\ ., .,,. • . _,.--,...,_ / '"-..,/-,/_-_· .. · .. · ,,,...,.-;:7·;::.,,_.-". / · ' . ,, I NO 1619 ' , ' ~ '-
/ -/ -~ '. ' 1 * \ CERTIFIED ) * !
K . /:' . " ,~ / ' \ ENGINEERING / / C ev1n ( Tngg. P.u. \ \fl_,GEOLOG1S7:/~/4 z, Wang, R .. E ·
Chief Engineering Geologi}t:\ ~>l-0J..!.k~0~~:J Senior Engineer. R.C.E. ~--°-~!3!-_:~-~J Date Signed: 5 / 8 / 202
;'\,, ~~'\..
_. . ..:;~; -....
James A. Stewart-Moore, M.Sc.
KAT/ZW/JSM:hsm
Distribution: Addressee Via Email
PA2020-259
-Newport"-~each
--
:::::8:::: ~ c:;;; C= C::J -Fi,-.--,--, JOB NO.
Coop Property
408 Via Lido Nord
Newport Beach
USGS Geologic Location Map, Santa Ana 30' x 60' Quadrangle
DATE:
72514-00 August 2020
PA2020-259
~ ~ c::::;;; ca c:::1 -Fir-rr, JOB NO.:
NEWPORT_ BEACH\)
•,. "'
Coop Property
408 Via Lido Nord
Newport Beach
--:~ ~tt:;:· .. ·
'-.. /4~~~~.
MAP EXPLANATION
Zones of Required Investigation:
Liquefaction
Areas where historic occurrence of liquefaction. or local geological,
geotechnical and groundwater conditions indicate a potential for
permanent ground displacements such that mitigation as defined in
Public Resources Code Section 2693(c) would be required.
Earthquake-Induced Landslides
Areas where previous occurrence of landslide movement, or local
topographic. geological, geotechnical and subsurface water conditions
indicate a potential for permanent ground displacements such that
mitigation as defined in Public ~sources Code Section 2693[cJ would
be required.
~ .... .:,,~_t< ''1,'• .. / -.,_ -+Xoi·' ~-(...... '' ~ I'
' ·<.. . / '<':...j~· ·~-l ?, , , ', ,_/-,: _/' ~ . -")2'$:; ·; /,.:i:)¥-:_ 1 .. -,, , ', _· I (
. ...,g?··· -~· ·~ ~ ,;·r.:;. r,Jt ~ . "'1 .. ,:"' cl.·;~';(: i i-.
, _. .... _ --~. , • -J ~ ;;-,... ,,......-..:::=i.__~.ai..;..,_ ......... :_ }·~;'./·p
-: • ,.-'~ ~--.. pi;.r· / =,_:;-_ --, . 26 ~;._•::,;; I · ,:,_,. :. ~ -... /1/ 1, ... ·--...._~~u.r,t11 NIQ..
/1 ·-. Ce,~
.J • .. ~.: _.. ~ i ,-u .... ~ ~•f-E ,,.' I
.......... , Miwl ; __ ;, ... !'-.... ii~---I* I f. ,,, ;. I_;, '.;-'
.. {r~.< ~
}·•_;:;t~i
/·~ _; ~--~~.~;-~i
~ > • _,
··. 4<i.s..., ·,._
-"< .. i:1-t~i~< :·:1_.;~---·_:_::-_·_·:~_~,~ -I }-""""" 36 _,.
--.... ;r &{,..;,,.,_~ ",\. ~.-. '. -,, 1.1.L,1,1
CDMG Geologic Hazards Location Map, Newport Beach Quadrangle
DATE: FIGURE:
72514-00 August 2020 2
PA2020-259
Typical O . N . S 'IC f Retaining n~1te at1~e ~• ap ~r
Wall ~xterior; (1.5-2.0 MAX. thick) ~ Select Noncohesive
Granular Backfill
SE~ 30)
C)Ef.:l
t;µl,!'~
Geotextile Filter Fabric ~?fl. .. · ·
Alternative Weep Hole{s)
for Exterior Applications,
Design per Architect or
Civil Engineer
Finish Grade -Design May
Vary per Architect or Civil
Engineer
Limit of Wall Excavation -
See Report for
Recommended Geometery
J---Single-sized 1/2"-3/4" Drain Rock
(1 cubic foot per lineal foot)
4" Perforated Plastic Collector Pipe
(Below Adjacent Finish Grade)
Notes: This system consists of a geotextile fabric-wrapped gravel envelope. Collection is with a
4-inch diameter perforated plastic pipe embedded in the gravel envelope and tied to a 4-inch
·diameter non-perforated plastic pipe which discharges at convenient locations. The outlet pipe
should be placed such that the flow gradient is not less than 2.0 percent. The geotextile fabric-
wrapped gravel envelope should be placed at a similar gradient
All drain pipes should be Schedule 40 PVC or ABS SDR-35. Perforations may be either bored
1 /4-inch diameter holes or 3/16-inch slots placed on the bottom one-third of the pipe perimeter. If the
pipe is to be bored, a minimum of 10 holes should be uniformly placed per foot of length. If slots are
made, they should not exceed 2-1/2 inches in length and should not be closer than 2 inches. Total
length of slots should not be less than 50 percent of the pipe length and should be uniformly spaced.
The fabric pore spaces should not exceed equivalent 30 mesh openings or be less than equivalent
100 mesh openings. The fabric should be placed such that a minimum lap of 8-inches exists at all
splices.
Typical Retaining Wall Subdrain Detail ~ c;;;;l=lc::J-Fir--r-r, 1-:J=os.....,.,,NO"'".-: ----------.... D"'"A'""T""E-: -----------,""Ft""U,.,,R""E.,..: ------1
72514-00 August 2020 3
PA2020-259
APPENDIX A
REFERENCES
PA2020-259
APPENDIX A
REFERENCES
I. Al Atik, Linda, M. ASCE, and Sitar, Nicholas, M.ASCE, 20 I 0, Seismic Earth Pressures
on Cantilever Retaining Structures, ASCE Journal of Geotechnical and
Geoenvironmental Engineering, dated October.
2. California Building Code, 2019 Edition.
3. California Division of Mines & Geology, 1998, "Seismic Hazards Zones Map, Newport
Beach Quadrangle."
4. California Geological Survey, 2008, "Guidelines for Evaluating and Mitigating Seismic
Hazards in California," Special Publication 117 A.
5. Geofirm, 1992, "Final As-built Rep011 34135 Calle la Primavera"; dated September 25,
Project No. 71052-00, Report No. 2-1087.
6. Geofirm, 2004, "Final Geotechnical Report, Single Family Residence Construction";
dated October 26, Project No: 71290-00, Report No: 04-5458.
7. Geofinn, 2005, "Geotechnical Investigation for Foundation Design, Proposed Single
Family Residence, 80 I Via Lido Saud, Newport Beach, California", dated August 29,
Project No. 71561-00, Report No. 05-5549.
8. Geofirm, 2007, "Preliminary Geotechnical Investigation for Foundation Design, Single
Family Residence, 149 Via Venezia, Newport Beach, California", dated January 24,
Project No. 71702-00, Report No. 07-5967.
9. Geofirm, 2020, "Preliminary Geotechnical Investigation, Proposed New Single-Family
Residence, 205 Via Karon, Newpo11 Beach, California", dated March 31, Project No.
72489-00, Report No. 20-8686.
I 0. Geofinn, 2020, "Preliminary Geotechnical Investigation, Proposed New Single-Family
Residence, 115 & 119 Via Mentone, Newport Beach, California", dated April 7, Project
No. 72488-00, Report No. 20-8683.
11. Grant et al, 1999, "Late Quaternary Uplift and Earthquake Potential of the San Joaquin
Hills, South Los Angeles Basin, California."
12. Jennings, C.W., and Bryant, W.A., 2010, Fault activity map of California: California
Geological Survey Geologic Data Map No. 6, map scale I :750,000.
PA2020-259
13. Legg, Mark R., et al, 2003, "Evaluation of Tsunami Risk to Southern California Coastal
Cities," Earthquake Engineering Research Institute. January
14. Morton, P.K., et al, 1973, "Geo-Environmental Maps of Orange County," California
Division of Mines and Geology, Preliminary Repo1t 15.
15. United States Geological Survey, 2002, "Preliminary Digital Geologic Map of the Santa
Ana 30' x 60' Quadrangle, southern California, Version 1.0".
16. United States Geological Survey -Earthquake Hazards Program, 2019, "Unified Hazards
Tool". Retrieved from https://earthquake.usgs.gov /hazards/interactive/index.php
17. United States Geological Survey -Earthquake Hazards Program, 2019, "Earthquake
Catalog" Retrieved from https://earthquake.usgs.gov/earthquakes/search/
PA2020-259
APPENDIX B
CONE PENETRATION TEST BORING LOG
PA2020-259
SUMMARY
OF
CoNE PENETRATION TEST DATA
Project:
Coop
408 Via Lido Nord
Newport Beach, CA
July 9, 2020
Prepared for:
Mr. James Stewart
Geofirm
14 Hughes, Ste B-101
Irvine, CA 92618
Office (949) 380-4886 / Fax (949) 455-9371
Prepared by: K1'T
KEHOE TESTING & ENGINEERING
5415 Industrial Drive
Huntington Beach, CA 92649-1518
Office (714) 901-7270 I Fax (714) 901-7289
www.kehoetesting.com
PA2020-259
TABLE OF CONTENTS
1. INTRODUCTION
2. SUMMARY OF FIELD WORK
3. FIELD EQUIPMENT & PROCEDURES
4. CONE PENETRATION TEST DATA & INTERPRETATION
APPENDIX
• CPT Plots
• CPT Classification/Soil Behavior Chart
· • CPT Data Files (sent via email)
PA2020-259
SUMMARY
OF
CONE PENETRATION TEST DATA
1. INTRODUCTION
This report presents the results of a Cone Penetration Test (CPT) program carried out for the
Coop project located at 408 Via Lido Nord in Newport Beach, California. The work was
performed by Kehoe Testing & Engineering (KTE) on July 9, 2020. The scope of work was
performed as directed by Geofirm personnel.
2. SUMMARY OF FIELD WORK
The fieldwork consisted of performing CPT soundings at one location to determine the soil
lithology. A summary is provided in TABLE 2.1 .
DEPTH OF
LOCATION CPT (ft) COMMENTS/NOTES:
CPT-1 11 Refusal
TABLE 2.1 -Summary of CPT Soundings
3. FIELD EQUIPMENT & PROCEDURES
The CPT soundings were carried out by KTE using an integrated electronic cone system
manufactured by Vertek. The CPT soundings were performed in accordance with ASTM
standards (05778). The cone penetrometers were pushed using a direct push rig anchored
with 3/4-inch concrete anchors. This rig has a pushing capacity of approximately 15 tons. The
cone used during the program was a 1 0 cmA2 and recorded the following parameters at
approximately 2.5 cm depth intervals:
• Cone Resistance (qc) • Inclination
• Sleeve Friction (fs) • Penetration Speed
• Dynamic Pore Pressure (u)
The above parameters were recorded and viewed in real time using a laptop computer. Data is
stored at the KTE office for up to 2 years for future analysis and reference. A complete set of
baseline readings was taken prior to each sounding to determine temperature shifts and any
zero load offsets. Monitoring base line readings ensures that the cone electronics are operating
properly.
PA2020-259
4. CONE PENETRATION TEST DATA & INTERPRETATION
The Cone Penetration Test data is presented in graphical form in the attached Appendix. These
plots were generated using the CPeT-IT program. Penetration depths are referenced to ground
surface. The soil behavior type on the CPT plots is derived from the attached CPT SBT plot
(Robertson, "Interpretation of Cone Penetration Test ... ", 2009) and presents major soil lithologic
changes. The stratigraphic interpretation is based on relationships between cone resistance
(qc), sleeve friction (fs), and penetration pore pressure (u). The friction ratio (Rf), which is
sleeve friction divided by cone resistance, is a calculated parameter that is used along with cone
resistance to infer soil behavior type. Generally, cohesive soils (clays) have high friction ratios,
low cone resistance and generate excess pore water pressures. Cohesionless soils (sands)
have lower friction ratios, high cone bearing and generate little (or negative) excess pore water
pressures.
The CPT data files have also been provided. These files can be imported in CPeT-IT (software
by Geologismiki) and other programs to calculate various geotechnical parameters.
It should be noted that it is not always possible to clearly identify a soil type based on qc, fs and
u. In these situations, experience, judgement and an assessment of the pore pressure data
should be used to infer the soil behavior type.
If you have any questions regarding this information, please do not hesitate to call our office at
(714) 901-7270.
Sincerely,
KEHOE TESTING & ENGINEERING
Steven P. Kehoe
President
07/14/20-kk-1937
PA2020-259
APPENDIX
PA2020-259
Z' ~
..c 0. (I)
0
Project: Geofirm
Kehoe Testing and Engineering
714-901-7270
steve@kehoetesting.com
www.kehoetesting.com
Location: 408 Via Lido Nord, Newport Beach, CA
Cone resista nee Sleeve friction
0 o~---------~
0.5 0.5
1 1 ---------
1.5 1.5 .... : ·----··--·--------·----------
2 2 . . ------·-·-·-··-··.· -·-··· -·-, ---··--·-······---
2.5
3 3
3 .5 3.5
4 4
4.5 4.5
5 5
5 .5 --5.5 ...,
~
6 -5 6 0.
6.5 Q.> 6.5 0
7 7 ···---·· -· --------------------
7.5 7.5
8 8
8.5
9
9.5
I - . · 1
8.5
9
9.5
10 10
10.5 10.5
11 11
11.5 11.5
Z' ~
-5 0. (I)
0
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7 .5·
8
8.5
9
9.5
10
10 .5
11
11.5
Pore pressure u
--------· --· .. -
12 12 12-+-----r-..--,---,---,--,--,----1
0 100 200 300
Tip resistance (tsf)
400 0 1 2 3 4
Friction (tsf)
-20 -10 0 10
Pressure (psi)
CPeT-ITv.2.3.1.9-CPTU data presentation & interpretation software-Report created on: 7/10/2020, 11:15:25 AM
Project file: C:\CPT ProJect Data\Geofirm-NewportBeach(408ViaUdoNord)7-20\CPT Report\Plots.cpt
20
Z' ~
..c ...,
0. Q.>
0
Friction ratio
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7 ..
7 .5 · --·-··,-·---·-·---·
8
8.5
9
9.5
10
10 .5
11
11.5
12-+---.--,--,--,---.--,-..-~
0 2 4 6 8
Rf(%)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
~ 5.5 ..., -~
..c 6 ...,
0.
(I) 6.5 0
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
0
CPT-1
Total depth: 11.31 ft, Date: 7/9/2020
Soil Behaviour Type
Silty sand & saooy silt
·Sitty s.nd· &-saooy-silt ···
Clay & silty clay
"Clay & silty clay·
Sand & s~ty sarv;I
Sand
2 4 6 8 10 12 14 16 18
SBT (Robertson, 2010)
PA2020-259
K
,i;,
(j
C
,1) ..... v,
T
E
0 .1
Kehoe Testing & Engineering
714-901-7270
steve@kehoetesting.com
www.kehoetesting.com
SOT plot
1
Friction R-::1ti o J Rf ('=·/~-)
SBT legend
II 1. Sensitive Ar,e grained LI 2, Org.:mi: mateti..:11
■ 3, Clay to ,lty cl,y
0 4. Clayey sit to <ii~/ cl,y
0 5, Si►.y sand to sandy silt
0 f,, Clean sand to siky sand
0 7. Gt~vely sM,i M sand
0 8. Vety stiff sand to clayey sand
0 9. Ver1 stiff Ane 9rained
10
PA2020-259
APPENDIXC
LIQUEFACTION ANALYSIS
PA2020-259
~r--
Geofirm/Stoney-Miller Consultants, Inc.
949-380-4886
~1....::::11& c::::, Mr-r-r-, www.stoneymiller.com
Project title : Geofirm
CPT file: CPT-1
Location : 408 Via Lido Nord, Newport Beach, CA
Input parameters and analysis data
Anaffsis me1hod: NCEER (1998)
Fines correction method: NCE!:R (1998)
Points to test: Based on le value
EarthQ.J;!ke magnitt.de M w: 7.30
Peak ground aa:eleration: 0.73
G.W.T. (in-situ]:
G.W.T. (earthq.):
Average results interval:
le cut·off value:
Unit weight calculation:
7.00 ft
7.00 ft
1
2.60
Based on SBT
Use fill:
Fill height:
Fil weigit:
Trans. detect. applied:
K0 applied:
No
N/A
N/A
No
Yes
Clay like behavior
applied:
Limit depth applied:
Limit depth:
MSF method:
Sands on!y
No
N/A
Method based
Cone resistance Friction Ratio SBTn Plot CRR plot FS Plot
0.5
1.5
2
2.5
3.5
4
4.5
----5 ~ ..c:: 5.5
'5. 6 ~ 6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
85
9
9.5
10
10.5
11 +-,-.,.....,,-,.,~....,.. ..... -,-i
0.5
1.5
2
2.5
3
3.5
4
45
5
5.5
6
6.5
7
7.5
8
8.5
9
9-5
10
10.5
11
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.S
7
7.5
8
8.5
9
9.5
10
10.5
11
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.S
11
'
~~i --· -· •• L. -~•, I ·. j
' ' --I .... ,. ·.• ++~ ~.,
' ' -:n ---~ -r-----~-t ~ L •-~-r •-• z ••
--tL--~~Lr~----
, ' --•---~--,-~ --' ' ' ' --i--,_ -' -~ ----
' ' I , . ~~:M~"M"'~r-~--••
nt,.-• .. • •t-.. •••: •
·-t-.. ·f·---,
I :
100
qt (tsf)
0 2 4 6 8 10
Rf(%)
1 2 3 4 0 0.2 0.4
CRR &CSR
O.E 0 0.5 1 1.5
--• x Jl ~ • 0 .;;
"' c£
"' VI ~ ~
',:' u >-:..J
Ic (Robertson 1990) Factor of safety
Mw=711~, sigmc1'= 1 atm base curve
0.8 -~--+----..... --+-------..... --+--+--..... --+--._,,t-
Liquefuction
0.7
0.6
0.5
0.4
0.3
0.2
0.1
NJ Li<Juefa<;tion
o+-~~-~-~~~~-~-~~~~-~~~~~~.-1-
0 20 40 60 80 100 120 140 160 180 200
Qtn,cs
Summary of liquefaction potential
0.1 1 10
Normalized friction ratio(%)
Zone A,: C-,.chc liqiJGfaction hlelydepending on size and du'a1ionof cy:licloading
Zone A2· C~lic liquefacfon and slrength loss. li'1ely depending on iooding aod grOU"ld
geon-etry
Zone 8. Liquefaction and post-earthquake strength I ass unlikely, check cy;,lic softerii ng
Zone C: Cy.:;lic liquefaction and strepgth loss possible depending on soil pasticity,
bf"ittl enessfsensiti\4 ty. slra.in to peak undrained slreng th ~nd g rO\.lnd geometry
Cliq v.3.D.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Uquefaction\72514-00.clq
PA2020-259
This software is licensed to: Stoney-Miller Consultants, Inc
CPT basic interpretation plots
Cone resistance Friction Ratio Pore pressure
0.5 0.5 . - --. ·--.. ------·-· ------0.5 0.5
1 1 -···-·-·· . ---1
1.5 1.5 1.5 1.5
2 2 2 2
2.5 2.5 2.5 2.5
3 3 3 3
3.5 3.5 3.5 3.5
4 4 4 4
4.5 4.5 4.5 4.5
5 5 5 5 g ~ ~ ~ ~ ~
5.5 5.5 -.. --·-,·--·--""' ""' 5.5 ""' ""' 5.5 0. 0. ~ 0. 6 <>. (lJ (lJ (lJ 6 (lJ 0 0 6 0 0 6
6.5 6.5
6.5 6.5
7 7
7 :\ 7
7.5 7.5 . --: \--
7.5 . \ 7.5
8 8 ·-\
8 \ B
8.5 8.5 \ 8.5 \ 8.5
9 9 ·\ 9 9
9.5 9.5 '
9.5 ···.-----· ·······"\. 9.5 10 10
10 . \ 10 10.5 10.5 \" 10.5 I 10.S 11 11 .... \
11 \ 11
50 100 150 0 2 4 6 8 10 ·l 0 1
qt (tsf} Rf(%) u (psi)
Input parameters and analysis data
A naff sis me1hod: NCEER (1998) Depth to water table (erthq.J: 7.00 ft Fil weiglt: N/A
F ines correction method: NCEER (1998) Average results interval: 1 Transition detect. applied: No
Points to test: Based on le value le cut-off value: 2.60 K0 applied: Yes
Earthcl)ake magnittde M w' 7.30 Unit weight calculation: Based on SBT Clay like behav br appled: Sands only
Peak ground acceleration: 0.73 use fill: No Limit depth applied:
Depth to water table (instu): 7.00 ft Fill height: N/A Limt depth:
Cliq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\]2450-72999\72514 Coop2\Liquefaction\72514-00.clq
No
N/A
CPT name: CPT-1
SBT Plot Soil Behaviour Type
0
0.5
,Silty ~nd: & :sandy silt
1.5
2
2.5
3
3.5
4 Saner& s[ty:sand
4.5
5
~ ~ 5.5 -5 Cl. 6 OJ 0
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
1 2 3 4 0 234567891011UDM~IBVIB
Ic(SBl) SBT (Robertson et al. 1986)
ssr legend
■ 1. Sensitive fine grained 0 4. Clayey silt to silty E] 7. Gravely sand to sand
■ 2. Org,mic material □ 5. Silty sand to sandy silt Im 8. Very stfff sand to
■ 3. Clay ID silty clay □ 6. Clean sand to silty sand □ 9. Very stiff fine grained
2
PA2020-259
This software is licensed to: Stoney·Miller Consultants, Inc
CPT basic interpretation plots (normalized)
Norm. cone resistance
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5 g 5.5 ~
.c .c 0. .... C. ., .,
0 0
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
D 100 200
Qtn
Input parameters and analysis data
A na~sis melhod: NCEER (1998)
Fines correction method: NCEER (1998)
Points to test: Based on le value
EarthQ.Jake magnitlde M w=
Peak ground acceleration:
Depth to water table (insitu):
7.30
0.73
7.00 ft
Norm. friction ratio
0.5 · ... --··--· ··--
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
D 2 4 6
Fr(%)
Depth to water table ( erthQ. ):
Average results interval;
Jc cut-off value:
Unit weight calculation:
Use fill:
Fill height:
8
7.00 ft
1
2.60
10
~ .c 0. .,
0
Based on SBT
No
N/A
Nom. pore pressure ratio
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
-0.2 0 0.2 0.4 0.6 0.8
Bq
Fil weight:
Transtion detect. applied:
K0 applied:
N/A
No
Yes
I
~ .... --£ Cl. .,
0
Clay like behav br appled:
Limit depth applied:
Sands only
No
Limit depth: N/A
CLiq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Liquefaction\72514-00.clq
SBTn Plot
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
B
8.5
9
9.5
10
10.5
11
1 2 3
le (Robertson 1990)
SBrnlegend
■ 1. Sensitive fine grained • 2. Organic material
■ 3. Clay to silty clay
CPT name: CPT-1
Norm. Soil Behaviour Type a
0.5
:Silty sand & :sandy silt
1
1.5
2
2.5
3
3.5
4 Sand & silty :sand
4.5
5 g 5.5 :5 Cl. 6 "' 0
6.5
7
7.5
8
8.5 ;~i:::: !:~: ::::
9
9.5 :Sand & siity :sand
10
10.5 :Sand
11
4 0 2 3 4 5 6 7 8 9101112131415161718
SBTn (Robertson 1990)
0 4. Clayey silt to silty [] 7. Gravely sand to sand
□ s'. Silty sand to sandy silt IE! 8. Very stiff sand to
El 6. Clean sand to silty sand □ 9. Very stiff fine grained
3
PA2020-259
This software is licensed to: Stoney-Miller Consultants, Inc
Liquefaction analysis overall plots (intermediate results)
Total cone resistance
0.5
1.5
2
2.5
3
3.5
4
4.5
: I 5
~ ,._
~ 5.5 £ Cl. cu 0 6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
so 100 150
qt {tsf)
Input parameters and analysis data
Anavsis method: NCEER (1998)
Fines rorrection method: NCEER (1998)
Points to test: Based on Ic value
Earthq.Jake magnitu:le M w'
Peak ground acceleration:
Depth to water table (insitu):
7.30
0.73
7.00 ft
SBTn Index
0.5
1.5
2
2.5
3
3.5
4
4.5
5 ~ ,._
~
£ 5.5
Cl. Cl) 0 6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
1 2 3
Ic {Robertson 1990)
Depth to water table ( erthq.):
Average results interval:
le cut-off value:
Unit weight calculation:
Use fill:
Fill height:
7.00 ft
1
2.60
Based on SBT
No
N/A
4
Norm. cone resistance
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5 g 5.5 £ Cl. 6 cu 0
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
0 100 200
Qtn
Fil weiglt:
Transition detect. applied:
N/A
No
Yes K~applied:
Clay like behav or appled:
Limt depth applied:
Limt depth:
Sands only
No
N/A
Cliq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Liquefaction\72514-00.clq
Grain char. factor
0.5 ........ ----·-·--•. - -. , -
1.5
2
2.5
3
3.5
4
4.5
5
~ :S 5.5 .s:::;
15. 6 (lJ 0
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
0 1 2 3 4 5 6 7 8
Kc
CPT name: CPT-1
Corrected norm. cone resistanc
0.5
1 ·-
1.5
2
I
2.5
I 3
_I
3.5
4
4.5
5 ~ :S 5.5 .s:::; 15.
I
Cl) 6 0
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
9 10 0 100 200
Qtn,cs
4
PA2020-259
This software is licensed to: Stoney-Miller Consultants, Inc
Liquefaction analysis overa ll plots
0.5
CRR plot
-----►-----·------' .
··-· --· -·r -----·f
' .
---·--.-• --r . '
1.5
2
2.5
3
3.5
4
4.5
_ .. -_________ .. _ ---------
_' ---· _____ J _______ ___I
~ ~ 5.5
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
0 0.2 0.4
CRR &CSR
Input parameters and analysis data
A nat{sis melhod: NCEER ( 1998)
Fines correction method: NCEER (1998)
O.E
Points to test: Based on le value
E arthQJake magnitl.de M w: 7.30
Peak ground acceleration: 0.73
Depth to water table (insitu): 7.00 ~
FS Plot
' ' ' 0.5 ---~-----.. ~ ' '. --! .1-.. ---1---,--...... -7_ .. __ .,.,.. ........
:J ::::-=t ·-_::=
1.5
2
2.5 ---i-......... -.. -~ .. ,.r~ .-
: l --~--.,._..,, .. .....,,:,.. ..... __ _
! i' --l _____ _.__r-----__,.
3
3.5
4 ---1----·i----~-
1 : ----:-------,------.. , 4.5 ' . ' ' ' ' --1---.-----r-----
----:------....;...:.-· .., ... I : ~ ! .. --,:----... --f-•---..
i f
5
~ ~ 5.5 ..c: Q. 6 QJ 0
6.5 ---r-----➔ .. ------
7
7.5
8
8.5
9
9.5
10
10.5 •--• •-•T••--.•-,••• ' .
11 i : : .. -.. -r .. ------
0 0.5 1 LS
Factor of safety
Depth to water table (erthq.): 7.00 ft
Average results interval: 1
le cut-off value: 2.60
Unit weight calculation: Based on SBT
Use fill: No
Fill height: N/A
Liquefaction potent ial
0.5
1.5
2 , ..........
2.5 , ..........
3 ·----
3.5 ·------
4
4.5
5
5.5 ~
..c:
6 C. ........... QJ 0
6.5 ...........
7 ·----
7.5 ·-
8
8.5
9
9.5
10
10.5
11
0 5 10 15 20
LPI
Fil weigit: N/A
Transition detect. applied: No
K0 applied: Yes
Clay like behav br appied: Sands only
Limit depth applied: No
Limit depth: N/A
0.5
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
Vertical settlements
! .. ' .. ' :---.. --------,----,•-·1··--..· ·r
I c:-t ~:t:r::::--:--., __
! . :
I •••I-•• . •• I •• • .... •---~•-••••• •••••••
l : ' : ! : ' : . ' .
I ' • • • • :::tr.:::-r-r:r-::: ;·· r:1
I : ! ' ! ! ! : ! I :--·:· t -r·-1 r-r-· ··r ··1
• • ' ' ' ' ' I !--+--:---:--+-+ ·+--,-f : : : : ' :
I ' • ' ◄ I • ·-----_______ .. ________ ----·--. ---.. ---' . ' ' ' ' ' I I i I 0 i...;--+-:·-++-i---: __ r->·
'.---~--o -+--~---1••• ; __ •T• .,. •r-• •
; t I I ; : : : : ~ . : ; . tt: ; rj : : -,-,--
r~::;:_;~r ·I _: __
I : : , , •
t-l--:-. : .. ;. _; __ ~--~-+ -~--_1
_; -~ ~ ·1-: :. : : --i--I
·i __ ; ::: ;-,-I
' ' . -4.-.J •• -J ........ ..
0 0.1 0.2 0.3 0.4 0.5 0.60.7 0.80.9
Settlement (in)
~ ._
..c:
C. QJ 0
F.S. color scheme
□ Almost certain it will liquefy
□ Very likely to liquefy
□ Liquefaction and no liq. are equally likely
□ Unlike to liquefy
□ Almost certain it will not liquefy
CPT name: CPT-1
Lateral displacements
0.5 · ···-------·--·· ----------------
1 ... -·-------------------
2 ·-----------------
2.5 ·-------------------------
3
3.5
4
4.5
5
5.5
6
7 ------------
7.5
8
8.5
9
10 ··-----------------
10.5 ----· ------·------
11 ------------
0
Displacement (in)
LPI color scheme
E] Very high risk
□ High risk D Low risk
Cliq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on : 8/18/2020, 3:39:27 PM 5
Project file: V:\72450· 72999\72514 Coop2\Liquefaction\72514·00.clq
PA2020-259
This software is licensed to: Stoney-Miller Consultants, Inc
~ C: ~ ·.;;
~
C: 0 :u ~ .;
C: .,
0.
l-o.. u
"O .,
.!::!
"' E 0 z
0.1 1
Normalized friction ratio(%)
Input parameters and analysis data
10
A naff sis method: NCEER (1998) Depth to water table { erthq.):
fines correction method: NCEER (1998}
Points to test: Based on le value
7.30
0.73
EarthQJake magnitu:le M ,.:
Peak ground acceleration:
Depth to water table (insitu): 7.00 ft
Average results interval:
le cut-off value:
Unit weight calculation:
Use fill:
Fill height:
Liquefaction analysis summary plots
0 .8 +--'--L---'----'-'--.L-.L-...,__...,_.......___,___.__,_.__.__-'-...,__-'-....._....+-
~ *
0.7
0.6
Bi 0.5 ~
* 0 ~ O: 0.4
~ ~
in '5 0.3
Ci
0.2
0.1
l.iqOefaction
•••
N:J Liquefad:ion
0 -+-,r,,r.,--.-,....-,......-rrT"T-.-r....-,......-T"T"T""T.....,,..,...,...,..T""T"T""T--r,-r-,-,-...-t-
7.00 ft
1
2.60
0
Based on SBT
No
N/A
20 40 60 80 100 120 140 160 180
Qtn,cs
Fil weight:
Transition detect. applied:
K0 applied:
C lay like behav i:Jr appled:
Limit depth applied:
Limit depth:
N/A
No
Yes
Sands only
No
N/A
200
Cliq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Liquefaction\72514-00.clq
I
N I
.;
>-.!!!
"O C: "' "' .,
:0 "' ~ Cl> :::, -~ --0
"' "' Cl> C: -"" u ~
CPT name: CPT-1
12.0 .. --.. Al)alysis PGft: 0.73
11.0
10.0
9.0
8.0
7.0
6.0
5.0
4.0
3.0
2.0
1.0
0.0 -,--.--.~-,-,r-.--r--r---r--.-~---r~r--.-.--.----,--,---.---1
0 2 3 4 5 6 7 8
Thickness of surface layer, Hl {m)
9 10
6
PA2020-259
This software is licensed to: Stoney-Miller consultants, Inc
Check for strength loss plots (Robertson (2010))
Norm. cone resistance
0.5
1
1.5
2
2.5
3
3.5
4
4.5
s
~ ~ 5.5 ..c 0. QJ 6 Cl
6.5
7.5
8
8.5
9
9.5
10
10.5
11
0 100 200
Qtn
Input parameters and analysis data
Anavsis me1hod: NCEER (1998)
F\nes correction method: NCEER (1998)
Points to test: Based on le value
7.30
0.73
Earthq,ake magnib.Jje M w:
Peak ground acceleration:
Depth to water table (insitu): 7.00 ft
Grain char. factor
0.5
1
1.5
2 ---·
2.5
3
3.5
4
4.5
s
~ ~ 5.5 ..c 0. 6 QJ Cl
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
o 1 2 3 4 5 6 7 B 9 10
Kc
Depth to water table ( erthq. ):
Average results inte,,,al:
re cut-off value:
Unit weight calculation:
Use fill:
Fill height:
7.00 ft
1
2.60
Based on SBT
No
N/A
Corrected norm. cone resistanc
0.5
3.5
4 ; ~ '
4.5 ·:-··--· ----·----~----------------------
7
7.5
8
8.5
9
9.5
10
10.5
0
Fil weig:it:
100
Qtn,cs
200
Transition detect. applied:
N/A
No
Yes K0 applied:
Clay like behav br appied:
Limit depth applied:
Limit depth:
Sands only
No
N/A
Cliq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Liquefaction\72514-00.clq
0.5
1
1.5
2
2.5
3
3.5
4
4.5
~ 5 ~ ..c 5.5 ..... Q. ~ 6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
SBTn Index
7
7.1
7.2
7.3
7.4
7.5
7.6
7.7
7.8
7.9
8
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8 ~ 8.9 ..c 9 0. "' 9.1 0 9.2
9.3
9.4
9.5
9.6
9.7
9.8
9.9
10
10.1
10.2
10.3
10.4
10.5
10.6
10.7
10.8
10.9
2 3 4
le {Robertson 1990)
0
CPT name: CPT-1
Liquefied Su/Sig'v
0.5
i· ... i '
<~ ~--~
1 1.5
Su/Sig'v
2 2.5
7
PA2020-259
This software is licensed to: Stoney-Miller Consultants, Inc
Estimation of post·earthquake settlements
Cone resistance SBTn Plot
0.5 0.5 0.5
1
1.5 1.5 1.5
2 2 2
2.5 2.5 2.5
3 3 3
3.5 3.5 3.5
4 4 4
4.5 4.5 4.5
5 5 5 -~ ~ ~ !!::, ~ -5.5 :=.. 5.5 .<: .<: 5.5 .<: 'o. 0. 'o. ., 6 ., ., 6 0 0 6 0
6.5 6.5
6.5
7 7
7
7.5 7.5
7.5
8 8
8
8.5 8.5
8.5
9 9
9
9.5 9.5
9.5
10 10
10 10.5 10.5
10.5 11 11
50 100 150 2 3 4 0
qt (tsf) le (Robertson 1990)
Abbreviations
q,: Total cone resistance (cone resistance q ccorrected for pore water effects)
I,: Soil Behaviour Type Index
FS: Cat:ulated Factor of Safety agairrt liquefaction
Volurnentric strain: Post-liquefaction volurnentric strain
CLiq v.3.0.2.4 -CPT Liquefaction Assessment Software -Report created on: 8/18/2020, 3:39:27 PM
Project file: V:\72450-72999\72514 Coop2\Liquefaction\72514-00.clq
FS Plot
' --+-r-.......... -. r·· ......... -,--_ 0.5
---~--------... ~ .-.. -------
--!··.
1.5
---~------. f__ .-. -·---2
---]--------t .·· -_-.. --2.5
' ' ' ' ___ i _____ ----1-----.. -. --3
---~---. -·-.+ · ____ -· -3.5
---➔---------. "{ ·--· ... ---4
' . : -: -... -.. --...... _ .... ._ _,,__.,. .. -._,_..,._ 4.5
:::L: --f ·. -·: 5
5.5
6
6.5
7
7.5
B
8.5
9
9.5
10
10.5
11
0.5 1 1.5 2
Factor of safety
CPT name: CPT-1
Strain plot Vertical settlements
I
0.5 i: I I r !
1.5 r !:
2 ! ,--r
2.5 /:
3 I i· :
3.5 ,. ,.
4 I ;·
I. 4.5 j:
I
5 .:
~ ! !!::, 5.5 I £ I a. 6 <IJ 0
6.5
7 7 7.5
8
8.5
9
9.5
10
10.5
11
0 1 2 3 4 5 6 0 0.1 0.2 0.3 0.4 0.5 0.6 0. 7 0.8 0.9
Volumentric strain (%) Settlement (in}
8
PA2020-259
APPENDIXD
STANDARD GRADING SPECIFICATIONS
PA2020-259
APPENDIX D
STANDARD GRADING SPECIFICATIONS
GENERAL
These specifications present the usual and minimum requirements for grading operations
observed by Geofirm or its designated representative. No deviation from these specifications
will be allowed, except where specifically superseded in the geotechnical report signed by a
registered geotechnical engineer.
The placement, spreading, mixing, watering and compaction of the fills in strict accordance with
these guidelines shall be the sole responsibility of the contractor. The construction, excavation,
and placement of fill shall be under the direct observation of the soils engineer signing the soils
report. If unsatisfactory soil-related conditions exist, the soils engineer shall have the authority
to reject the compacted fill ground and, if necessary, excavation equipment will be shut down to
permit completion of compaction. Conformance with these specifications will be discussed in
the final report issued by the soils engineer.
SITE PREPARATION
All brush, vegetation and other deleterious material such as rubbish shall be collected, piled and
removed from the site prior to placing fill, leaving the site clear and free from objectionable
material.
Soil, alluvium, or rock materials determined by the soils engineer as being unsuitable for
placement in compacted fills shall be removed from the site. Any material incorporated as part
of a compacted fill must be approved by the soils engineer.
The surface shall then be plowed or scarified to a minimum depth of 6 inches until the surface is
free from uneven features that would tend to prevent uniform compaction by the equipment used.
After the area to receive fill has been cleared and scarified, it shall be diced or bladed by the
contractor until it is uniform and free from large clods, brought to the proper moisture content
and compacted to minimum requirements. If the scarified zone is greater than 12 inches in
depth, the excess shall be removed and placed in lifts restricted to 6 inches.
Any underground structures such as cesspools, cisterns, mining shafts, tunnels, septic tanks,
wells, pipe lines or others not located prior to grading are to be removed or treated in a manner
prescribed by the soils engineer.
MATERIALS
Materials for compacted fill shall consist of materials approved by the soils engineer. These
materials may be excavated from the cut area or impo11ed from other approved sources, and soils
from one or more sources may be blended. Fill soils shall be free from organic vegetable matter
and other unsuitable substances. Normally, the material shall contain no rocks or hard lumps
PA2020-259
greater than 6 inches in size and shall contain at least 50 percent of material smaller than 1/4-
inch in size. Materials greater than 4 inches in size shall be placed so that they are completely
surrounded by compacted fines; no nesting of rocks shall be permitted. No material of a
perishable, spongy, or otherwise of an unsuitable nature shall be used in the fill soils.
Representative samples of materials to be utilized as compacted fill shall be analyzed in the
laboratory by the soils engineer to determine their physical properties. If any material other than
that previously tested is encountered during grading, the appropriate analysis of this material
shall be conducted by the geotechnical engineer as soon as possible.
PLACING, SPREADING, AND COMPACTING FILL MATERIAL
The material used in the compacting process shall be evenly spread, watered, processed and
compacted in thin lifts not to exceed 6 inches in thickness to obtain a uniformly dense layer.
When the moisture content of the fill material is below that specified by the soils engineer, water
shall be added by the contractor until the moisture content is near optimum as specified.
When the moisture content of the fill material is above that specified by the geotechnical
engineer, the fill material shall be aerated by the contractor by blading, mixing, or other
satisfactory methods until the moisture content is near optimum as specified.
After each layer has been placed, mixed, and spread evenly, it shall be thoroughly compacted to
90 percent of the maximum laboratory density in compliance with ASTM D: 1557-70 (five
layers). Compaction shall be accomplished by sheepsfoot rollers, vibratory rollers, multiple-
wheel pneumatic-tired rollers, or other types of acceptable compacting equipment. Equipment
shall be of such design that it will be able to compact the fill to the specified density.
Compaction shall be continuous over the entire area and the equipment shall make sufficient
passes to obtain the desired density uniformly.
A minimum relative compaction of90 percent out to the finished slope face of all fill slopes will
be required. Compacting of the slopes shall be accomplished by backrolling the slopes in
increments of 2 to 5 feet in elevation gain or by overbuilding and cutting back to the compacted
inner core, or by any other procedure which produces the required compaction.
OBSERVATIONS AND TESTING
The geotechnical engineer shall observe the placement of fill during the grading process and will
file a written report upon completion of grading stating his observations as to compliance with
these specifications.
One density test shall be required for each 2 vertical feet of fill placed, or one for each 1,000
cubic yards of fill, whichever requires the greater number of tests.
PA2020-259
Any cleanouts and processed ground to receive fill must be observed by the soils engineer and/or
engineering geologist prior to any fill placement. The contractor shall notify the geotechnical
engineer when these areas are ready for observation.
PROTECTION OF WORK
During the grading process and prior to the complete construction of permanent drainage
controls, it shall be the responsibility of the contractor to provide good drainage and prevent
ponding of water and damage to adjoining properties or to finished work on the site.
After the geotechnical engineer has terminated his observations of the completed grading, no
further excavations and/or filling shall be performed without the approval of the soils engineer, if
it is to be subject to the recommendations of this report.
PA2020-259
APPENDIXE
UTILITY TRENCH BACKFILL GUIDELINES
PA2020-259
APPENDIX E
UTILITY TRENCH BACKFILL GUIDELINES
The following guidelines pe11inent to utility trench backfills have been adopted by the County of
Orange, Environmental Management Agency Grading Section, effective March 31, 1986. The
application of the guidelines is strictly enforced by the County reviewers and inspectors.
I. Each utility subcontractor (gas, electric, water, sewer, telephone, cable TV, irrigation,
drainage, etc.) shall submit to the developer for dissemination to his consultants (civil
engineer, geotechnical engineer, and utility contractor) a plot plan of utility lines installed
under his purview which identifies line type, material, size, depth, and approximate
location.
2. The developer or his agent shall provide a composite plot plan of all utilities or a copy of
l!.!l individual utility plot plans to his geotechnical engineer for use in evaluating whether
all utility trench backfills are suitable for the intended use.
3. The geotechnical engineer shall provide the County with a repo11 which includes a plot
plan showing the location of l!.!l utility trenches which:
A. Are located within the load influence zone ofa structure (I :I projection)
B. Are located beneath any hardscape
C. Are parallel and in close proximity to the top or toe of a slope and may adversely
impact slope stability if improperly backfilled
D. Are located on the face of a slope in a trench 18 or more inches in depth.
Typically, trenches that are less than 18 inches in depth will not be within the load
influence zone if located next to a structure, and will not have a significant effect on
slope stability if constructed near the top or toe of a slope and need not be shown on the
plot plan unless determined to be significant by the geotechnical engineer. This plot plan
may be prepared by someone other than the soil engineer, but must meet his approval.
4. Backfill compaction test locations must be shown on the plot plan described in No. 3
above, and a table of test data provided in the geotechnical report.
5. The geotechnical report (utility trench backfill) must state that l!.!l utility trenches within
the subject lots have been backfilled in a manner suitable for the intended use. This
includes the backfill of all trenches shown on the plot plan described in No. 3 and the
backfill of those trenches which did not need to be plotted on this plan.
PA2020-259