HomeMy WebLinkAbout5208-A; RECYCLED WATER PHASE III PIPELINE EXPANSION SEGMENT 9; GEOTECHNICAL EVALUATION; 2016-06-14GEOTECHNICAL EVALUATION
RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
PREPARED FOR:
Infrastructure Engineering Corporation
14271 Danielson Street
Poway, California 92064
PREPARED BY:
Ninyo & Moore
Geotechnical and Environmental Sciences Consultants
5710 Ruffin Road
San Diego, California 92123
June 14, 2016
Project No. 108153001
5208-A
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TABLE OF CONTENTS
Page
1. INTRODUCTION ....................................................................................................................1
2. SCOPE OF SERVICES ............................................................................................................1
3. PROJECT AND SITE DESCRIPTION ...................................................................................2
4. FIELD EXPLORATION AND LABORATORY TESTING ..................................................2
5. GEOLOGY AND SUBSURFACE CONDITIONS .................................................................3
5.1. Regional and Geologic Setting .....................................................................................3
5.2. Site Geology .................................................................................................................4
5.2.1. Fill .......................................................................................................................4
5.2.2. Old Paralic Deposits ............................................................................................4
5.3. Groundwater .................................................................................................................4
6. GEOLOGIC HAZARDS ..........................................................................................................5
6.1. Faulting and Seismicity ................................................................................................5
6.1.1. Ground Surface Rupture .....................................................................................5
6.1.2. Strong Ground Motions ......................................................................................5
6.1.3. Liquefaction and Seismically Induced Settlement ..............................................6
6.2. Landsliding ...................................................................................................................6
7. CONCLUSIONS ......................................................................................................................7
8. RECOMMENDATIONS ..........................................................................................................8
8.1. Earthwork .....................................................................................................................8
8.1.1. Site Preparation ...................................................................................................8
8.1.2. Excavation Characteristics ..................................................................................8
8.1.3. Temporary Excavations and Shoring ..................................................................9
8.1.4. Excavation Bottom Stability .............................................................................10
8.1.5. Pipe Bedding and Pipe Zone Backfill ...............................................................10
8.1.6. Modulus of Soil Reaction (E') ...........................................................................10
8.1.7. Trench Zone Backfill Materials ........................................................................11
8.1.8. Fill Placement and Compaction ........................................................................11
8.2. Lateral Pressures for Thrust Blocks and Jacking ........................................................12
8.3. Pavement Reconstruction ...........................................................................................12
8.4. Corrosivity ..................................................................................................................12
8.5. Concrete Placement ....................................................................................................13
8.6. Pre-Construction Conference ......................................................................................13
8.7. Plan Review and Construction Observation ...............................................................13
9. LIMITATIONS .......................................................................................................................14
10. REFERENCES .......................................................................................................................16
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Figures
Figure 1 – Site Location
Figure 2 – Boring Locations
Figure 3 – Fault Locations
Figure 4 – Geology
Figure 5 – Lateral Earth Pressures for Braced Excavation
Figure 6 – Thrust Block Lateral Earth Pressure Diagram
Appendices
Appendix A – Boring Logs
Appendix B – Laboratory Testing
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1. INTRODUCTION
In accordance with your request and our proposal dated January 4, 2016, we have performed a
geotechnical evaluation for the proposed Recycled Water Phase III, Pipeline Segment 9 Project
located in Carlsbad, California (Figure 1). This report presents our findings and conclusions
regarding the geotechnical conditions along the subject alignments and our recommendations
for the design and construction of this project.
2. SCOPE OF SERVICES
Ninyo & Moore’s scope of services for this project included review of pertinent background da-
ta, performance of a geologic reconnaissance, subsurface exploration, and engineering analysis
with regard to the proposed project. Specifically, we performed the following tasks:
Reviewing background information including available topographic maps, geologic data, fault
maps, aerial photographs, and a provided alignment figure.
Coordinating and mobilizing for a geotechnical reconnaissance to observe the existing site
conditions and to mark-out the boring locations for utility clearance by Underground Service
Alert (USA).
Obtaining traffic control plans from a traffic control subcontractor and right of way permits
from the City of Carlsbad.
Performing a subsurface exploration program consisting of excavating, logging, and sampling of
four exploratory borings.
Performing geotechnical laboratory testing on representative soil samples to evaluate ge-
otechnical characteristics and design parameters.
Performing geotechnical analysis of the data obtained from our site reconnaissance, subsur-
face exploration, and laboratory testing.
Preparing this report presenting our findings, conclusions, and recommendations regarding
the geotechnical design and construction of the project.
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3. PROJECT AND SITE DESCRIPTION
We understand that the project will consist of expanding the existing recycled water piping sys-
tem for the City of Carlsbad. This project area is referred to as Pipeline Segment 9. Pipeline
Segment 9 will include the installation of 1,420 lineal feet of 8-inch diameter polyvinyl chlo-
ride (PVC) piping along Ponto Drive, 1,460 lineal of 6-inch diameter PVC piping along
Navigator Circle, and 1,750 lineal feet of 8-inch diameter PVC piping along Avenida Encinas.
The invert depths of the piping are anticipated to be approximately 4 1/2 feet below finished
ground surface. The new segments will connect to the existing recycled water line at two inter-
connection vaults, which are to be located at the intersection of Poinsettia Lane and Avenida
Encinas and at the intersection of Ponto Drive and Avenida Encinas.
Surface elevations along Pipeline Segment 9 range from a low of approximately 40 feet above
mean sea level (MSL) near the north end of Ponto Drive to a high of approximately 105 feet
above MSL at the east portion of Navigator Circle.
4. FIELD EXPLORATION AND LABORATORY TESTING
Our subsurface exploration was conducted on May 17, 2016 and consisted of drilling, logging,
and sampling of four small-diameter exploratory borings (B-1 through B-4). The borings were
drilled to depths up to approximately 16 ½ feet using a truck-mounted drill rig equipped with 8-inch
diameter, hollow-stem augers. During the drilling operations, the borings were logged and sampled
by Ninyo & Moore personnel. Representative bulk and in-place soil samples were obtained from
within the borings. The samples were then transported to our in-house geotechnical laboratory for
testing. The approximate locations of the exploratory borings are shown on Figure 2. As depicted on
Figure 2, boring B-1 was performed within the area for the pipeline expansion along Avenida
Encinas, borings B-2 and B-3 were performed within the area for the pipeline expansion along
Ponto Drive, and boring B-4 was performed within the area for the pipeline expansion along
Navigator Circle. Logs of the borings are included in Appendix A.
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The geotechnical laboratory testing that was performed on representative soil samples included
an evaluation of in-situ dry density and moisture content, gradation (sieve) analysis, shear
strength, and soil corrosivity. The results of the in-situ dry density and moisture content tests are
presented on the boring logs in Appendix A. The results of the other laboratory tests are present-
ed in Appendix B.
5. GEOLOGY AND SUBSURFACE CONDITIONS
Our findings regarding regional and site geology along with groundwater conditions at the pro-
ject alignments are provided in the following sections.
5.1. Regional and Geologic Setting
The project area is situated in the coastal foothill section of the Peninsular Ranges Geo-
morphic Province. This geomorphic province encompasses an area that extends
approximately 900 miles from the Transverse Ranges and the Los Angeles Basin south to
the southern tip of Baja California (Harden, 2004; Norris and Webb, 1990). The province
varies in width from approximately 30 to 100 miles. In general, the province consists of rug-
ged mountains underlain by Jurassic metavolcanic and metasedimentary rocks, and
Cretaceous igneous rocks of the Southern California Batholith. The portion of the province
in San Diego County that includes the project area consists generally of Quaternary and Ter-
tiary age sedimentary rock.
The Peninsular Ranges Province is traversed by a group of sub-parallel faults and fault
zones trending roughly northwest. Several of these faults, which are shown on Figure 3, are
considered active faults. The Elsinore, San Jacinto, and San Andreas faults are active fault
systems located northeast of the project area and the Rose Canyon, Coronado Bank, San Di-
ego Trough, and San Clemente faults are active faults located west of the project area. The
Rose Canyon Fault Zone, the nearest active fault system, has been mapped less than 4 miles
west of the project alignments. Major tectonic activity associated with these faults within
this regional tectonic framework consists primarily of right-lateral, strike-slip movement.
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5.2. Site Geology
Geologic units encountered during our reconnaissance and subsurface exploration in-
cluded fill and old paralic deposits (Kennedy and Tan, 2007). Generalized descriptions
of the earth units encountered are provided in the subsequent sections. Additional de-
scriptions of the subsurface units are provided on the boring logs in Appendix A. For
further reference, a geologic map of the region is presented on Figure 4.
5.2.1. Fill
Fill was encountered in each of our exploratory borings beneath the pavement sections
and extending to depths up to approximately 8 feet. As encountered, the fill generally
consisted of various shades of brown and gray, moist, medium dense, silty sand. Gravel
and brick fragments were observed within the encountered fill materials.
5.2.2. Old Paralic Deposits
Quaternary-age old paralic deposits were encountered in our exploratory borings underlying
the fill materials and extending to the total depth explored of approximately 16 ½ feet. As
encountered, the old paralic deposits generally consisted of various shades of brown, moist,
medium dense to very dense, silty sand.
5.3. Groundwater
Groundwater was not encountered during our subsurface exploration. Our review of back-
ground documents indicates that groundwater is present at depths greater than 20 feet.
However, soils above their optimum moisture were encountered in our boring B-2 just be-
low the pavement section. Additionally, existing utility trench lines may act as conduits for
perched water conditions. Due to the site topography, nearby areas of landscaping, and the
potential presence for existing utility trench lines, zones of seepage and/or perched water
should be anticipated. Fluctuations in the groundwater level and perched water conditions
may occur due to variations in ground surface topography, subsurface geologic conditions
and structure, rainfall, irrigation, tidal fluctuations, and other factors.
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6. GEOLOGIC HAZARDS
In general, hazards associated with seismic activity include ground surface rupture, strong ground
motion, liquefaction, and landslides. These considerations are discussed in the following sections.
6.1. Faulting and Seismicity
The project area is considered to be seismically active. Based on our review of the refer-
enced geologic maps and stereoscopic aerial photographs, as well as our geologic field
reconnaissance, the subject alignments are not underlain by known active or potentially ac-
tive faults (i.e., faults that exhibit evidence of ground displacement in the last 11,000 years
and 2,000,000 years, respectively). Major known active faults in the region consist generally
of en-echelon, northwest-striking, right-lateral, strike-slip faults. These include the Rose
Canyon, Coronado Bank, San Diego Trough, and San Clemente faults, located to the west of
the site, and the Elsinore, San Jacinto and San Andreas faults, located to the east of the site.
The locations of these faults are shown on Figure 3.
The closest known active fault is the Rose Canyon fault, which can generate an earthquake
maximum moment magnitude Mmax of up to 7.2 as published for the CGS by Cao et al.
(2003). It is located less than 4 miles west of the project segments.
6.1.1. Ground Surface Rupture
Based on our review of the referenced literature and our site reconnaissance, no active
faults are known to cross the project site or pipeline alignments. Therefore, the potential
for ground rupture due to faulting at the site is unlikely. However, lurching or cracking
of the ground surface as a result of nearby seismic events is possible.
6.1.2. Strong Ground Motions
The 2013 California Building Code (CBC) specifies that the Risk-Targeted, Maximum
Considered Earthquake (MCER) ground motion response accelerations be used to eval-
uate seismic loads for design of buildings and other structures. The MCER ground
motion response accelerations are based on the spectral response accelerations for
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5 percent damping in the direction of maximum horizontal response and incorporate a
target risk for structural collapse equivalent to 1 percent in 50 years with deterministic
limits for near-source effects. The horizontal peak ground acceleration (PGA) that cor-
responds to the MCER for the segments was calculated as 0.47g using the United States
Geological Survey (USGS, 2016) seismic design tool (web-based).
The 2013 CBC specifies that the potential for liquefaction and soil strength loss be
evaluated, where applicable, for the Maximum Considered Earthquake Geometric Mean
(MCEG) peak ground acceleration with adjustment for site class effects in accordance
with the American Society of Civil Engineers (ASCE) 7-10 Standard. The MCEG peak
ground acceleration is based on the geometric mean peak ground acceleration with a
2 percent probability of exceedance in 50 years. The MCEG peak ground acceleration
with adjustment for site class effects (PGAM) was calculated as 0.48g using the USGS
(USGS, 2016) seismic design tool that yielded a mapped MCEG peak ground accelera-
tion of 0.47g for the site and a site coefficient (FPGA) of 1.032 for Site Class D.
6.1.3. Liquefaction and Seismically Induced Settlement
Liquefaction of cohesionless soils can be caused by strong vibratory motion due to
earthquakes. Research and historical data indicate that loose granular soils and non-
plastic silts that are saturated by a relatively shallow groundwater table are susceptible
to liquefaction. Based on the relatively dense nature of the old paralic deposits underly-
ing the pipeline alignments, liquefaction and the resulting seismically induced
settlements are not design considerations.
6.2. Landsliding
No landslides or indications of deep-seated landslides were noted underlying the project site dur-
ing our field exploration or our review of available geologic literature and topographic maps.
Our review of Tan (1995) indicates that the alignment is situated in Landslide Susceptibility Ar-
ea 2, which represents areas that are marginally susceptible to landsliding.
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7. CONCLUSIONS
Based on our review of the referenced background data and the results of our subsurface explora-
tion, it is our opinion that construction of the proposed project is feasible from a geotechnical
standpoint provided that the recommendations of this report are incorporated into the preliminary
design of the project. Geotechnical considerations include the following:
Based on the results of our background review and subsurface exploration, the geologic
units that underlie the project segments include fill and old paralic deposits.
The on-site fill and old paralic deposits should be generally excavatable with conventional
heavy-duty earth moving construction equipment in generally good condition.
Materials derived from on-site excavations are generally considered suitable for reuse as back-
fill, provided they meet the recommendations for backfill materials presented in the following
sections.
Due to the granular nature of the fill and old paralic deposits in the vicinity of our exploratory
borings, the contractor should anticipate encountering caving and/or sloughing conditions when
excavating these materials.
Although groundwater was not encountered, soils above optimum moisture content were en-
countered in boring B-2. Additionally, perched water conditions may be present within the
project alignment areas. The contractor should be prepared to address issues associated with
seepage and perched water conditions such as excavation stability, dewatering, and the pres-
ence of soils above optimum moisture content proposed for reuse as backfill material.
Soils above their optimum moisture content were encountered during our subsurface explo-
ration within boring B-2. Therefore, the contractor should anticipate additional processing of
these materials (including aeration) prior to reuse as backfill.
Based on the soil corrosivity testing presented in Appendix B, test results indicate the soils
along the project alignments are not considered corrosive based on ACI 318 and Caltrans
corrosion criteria (2012).
No active faults are reported underlying or adjacent to the alignments. The active Rose Can-
yon fault has been mapped less than 4 miles west of the segments.
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8. RECOMMENDATIONS
The following sections include our geotechnical recommendations for the design of the proposed
project. These recommendations are based on our evaluation of the site geotechnical conditions
and our understanding of the planned construction.
8.1. Earthwork
In general, earthwork should be performed in accordance with the recommendations pre-
sented in this report. Ninyo & Moore should be contacted for questions regarding the
recommendations or guidelines presented herein.
8.1.1. Site Preparation
Prior to performing site excavations, the site should be cleared of vegetation, surface
obstructions, rubble and debris, abandoned utilities and foundations, and other deleteri-
ous materials. Existing utilities within the project limits, if any, should be re-routed or
protected from damage by construction activities. Obstructions that extend below finish
grade, if any, should be removed and the resulting holes filled with compacted soils.
Materials generated from the clearing operations should be removed from the project
site and disposed of at a legal dumpsite.
8.1.2. Excavation Characteristics
Our evaluation of the excavation characteristics of the on-site materials is based on the
results of our exploratory borings, our site observations, and our experience with similar
materials. In our opinion, the existing fill and old paralic deposits are generally expected
to be rippable with heavy-duty trenching equipment to the anticipated construction
depths. Due to the granular nature of the fill and old paralic deposits in the vicinity of our
exploratory borings, the contractor should anticipate encountering caving and/or sloughing
conditions when excavating these materials.
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8.1.3. Temporary Excavations and Shoring
For temporary excavations, we recommend that the following Occupational Safety and
Health Administration (OSHA) soil classifications be used:
Fill and Old Paralic Deposits Type C
Upon making the excavations, the soil classifications and excavation performance
should be evaluated in the field by the geotechnical consultant in accordance with the
OSHA regulations. Temporary excavations should be constructed in accordance with
OSHA recommendations. For trenches or other excavations, OSHA requirements re-
garding personnel safety should be met using appropriate shoring (including trench
boxes) or by laying back the slopes to no steeper than 1.5:1 (horizontal to vertical) in
fill and old paralic deposits. Temporary excavations that encounter seepage may be
shored or stabilized by placing sandbags or gravel along the base of the seepage zone.
Excavations encountering seepage should be evaluated on a case-by-case basis. On-site
safety of personnel is the responsibility of the contractor.
In areas with limited space for construction where temporary excavations may not be laid
back at the recommended slope inclination, a shoring system with bracing may be incor-
porated to stabilize the excavation sidewalls during construction. The shoring system
should be designed using the magnitude and distribution of lateral earth pressures pre-
sented on Figure 5. The recommended design earth pressures are based on the
assumptions that (a) the shoring system is constructed without raising the ground surface
elevation behind the shoring, (b) that there are no surcharge loads, such as soil stockpiles,
construction materials, construction equipment, or vehicular traffic, and (c) that no loads
act above a 1:1 plane extending up and back from the base of the shoring system. For
shoring subjected to the above-mentioned surcharge loads, the contractor should include
the effect of these loads on lateral earth pressures acting on the shoring wall.
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8.1.4. Excavation Bottom Stability
In general, we anticipate that the bottom of the excavations will be stable and should
provide suitable support to the proposed pipeline. Excavations which are close to or ex-
tend below the water table (if encountered) may be unstable. In general, unstable
bottom conditions may be mitigated by overexcavating the excavation bottom to suita-
ble depths and replacing with a 6 to 12-inch layer of compacted ¾ to 1½-inch crushed
gravel, that is encased in Mirafi® 600X woven geotextile, or an approved equivalent.
Recommendations for stabilizing excavation bottoms should be based on evaluation in
the field by the geotechnical consultant at the time of construction.
8.1.5. Pipe Bedding and Pipe Zone Backfill
We recommend that pipes be supported on 6 inches or more of granular bedding materi-
al. Pipe bedding and pipe zone backfill typically consists of graded aggregate with a
coefficient of uniformity of three or more. Pipe bedding and pipe zone backfill should be
sand that has a Sand Equivalent (SE) of 30 or more with no material larger than
1/2-inch (City of Carlsbad, 2016a). These materials should be placed below, around the
sides, and on top of the pipe. In addition, the pipe zone backfill should extend 1 foot or
more above the top of the pipe (City of Carlsbad, 2016b).
It has been our experience that the voids within a crushed rock material are sufficiently
large to allow fines to migrate into the voids, thereby creating the potential for sinkholes
and depressions to develop at the ground surface. If open-graded gravel is utilized as
pipe zone backfill, this material should be separated from the adjacent trench sidewalls
and overlying trench backfill with a geosynthetic filter fabric.
8.1.6. Modulus of Soil Reaction (E')
The modulus of soil reaction (E') is used to characterize the stiffness of soil backfill placed
at the sides of buried flexible pipes for the purpose of evaluating deflection caused by the
weight of the backfill over the pipe (Hartley and Duncan, 1987). A soil reaction modulus of
1,200 pounds per square inch (psi) may be used for an excavation depth of up to about
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5 feet when backfilled with granular soil compacted to a relative compaction of 90 percent
as evaluated by the ASTM International (ASTM) D 1557. A soil reaction modulus of
1,800 psi may be used for trenches deeper than 5 feet.
8.1.7. Trench Zone Backfill Materials
In general, on-site soils with an organic content of less than approximately 3 percent by
volume (or 1 percent by weight) that meet the following gradations are considered suit-
able for reuse as trench zone backfill. For the purpose of this report, the trench zone is
considered to extend from 1 foot above the top of the pipe to the top of the trench. The
backfill material should not generally contain rocks or lumps larger than approximately
3 inches, and particles not more than approximately 30 percent larger than ¾ inch.
Larger chunks, if generated during excavation, may be broken into acceptably sized
pieces or disposed of offsite. Imported fill material, if needed for the project, should
generally be granular soils. Materials for use as backfill should be evaluated by
Ninyo & Moore’s representative prior to filling or importing.
8.1.8. Fill Placement and Compaction
Fill and trench backfill should be compacted by mechanical methods in horizontal lifts
to a relative compaction of 90 percent as evaluated by the latest edition of
ASTM D 1557. The upper 12 inches of street subgrade and aggregate base materials
beneath pavement areas should be compacted to a relative compaction of 95 percent.
Fill and trench backfill soils should be placed at or above the laboratory optimum mois-
ture content as evaluated by the latest edition of ASTM D 1557. The optimum lift
thickness of fill will depend on the type of compaction equipment used, but generally
should not exceed 8 inches in loose thickness. Successive lifts should be treated in a like
manner until the desired finished grades are achieved. Special care should be taken to
avoid pipe damage when compacting trench backfill above the pipe.
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8.2. Lateral Pressures for Thrust Blocks and Jacking
Thrust restraint for buried pipelines and lateral pressures for jacking may be achieved by trans-
ferring the thrust force to the soil outside the pipe through a thrust block. Thrust blocks may be
designed using the lateral passive earth pressures presented on Figure 6. Thrust blocks should be
backfilled with granular backfill material, compacted as outlined in this report.
8.3. Pavement Reconstruction
Trench excavations in existing pavement areas may involve replacement of pavements as
part of the work. In general, trench pavement repair should include asphalt concrete (AC)
that is 1 inch thicker than the existing AC pavement section, and be 4 inches or more in
thickness. Also the AC and aggregate base materials should conform to the material thick-
nesses and compaction requirements of the adjacent pavement section. Subgrade and
aggregate base materials should be compacted to 95 percent relative compaction as evaluat-
ed by ASTM D 1557. AC should be compacted to 95 percent relative compaction as
evaluated by ASTM D1561 (Hveem density). Actual pavement reconstruction should con-
form to the requirements of the city/agency of jurisdiction.
8.4. Corrosivity
Laboratory testing was performed on representative samples of near-surface soils to evaluate
soil pH, electrical resistivity, water-soluble chloride content, and water-soluble sulfate con-
tent. The soil pH and electrical resistivity tests were performed in general accordance with
California Test (CT) 643. Chloride content tests were performed in general accordance with
CT 422. Sulfate testing was performed in general accordance with CT 417. The laboratory
test results are presented in Appendix B.
The pH values of the tested samples ranged from 6.9 to 7.1. The electrical resistivities of the
tested samples ranged from approximately 3,300 to 18,000 ohm-centimeters. The chloride
contents of the tested samples ranged from approximately 65 to 140 ppm. The sulfate con-
tents of the tested samples ranged from approximately 0.002 to 0.009 percent by weight
(i.e., 20 to 90 ppm). Based on the laboratory test results, as compared to ACI 318 and Cal-
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trans (2012) corrosion criteria, the soils along the project alignments would not be classified
as corrosive, which is defined as having earth materials with an electrical resistivity of less
than 1,000 ohm-centimeters, more than 500 ppm chlorides, more than 0.10 percent sulfates
(i.e., 1,000 ppm), and/or a pH of 5.5 or less.
8.5. Concrete Placement
Concrete in contact with soil or water that contains high concentrations of soluble sulfates can
be subject to chemical deterioration. Laboratory testing indicated sulfate contents ranging
from approximately 0.002 to 0.009 percent, which is considered to represent a negligible po-
tential for sulfate attack (ACI, 318). However, due to the potential for variability of soils, the
proximity of the pipeline segments to the Pacific Ocean, and the potential use of recycled wa-
ter, we recommend using Type II/V or V cement for concrete structures in contact with soil.
8.6. Pre-Construction Conference
We recommend that a pre-construction meeting be held prior to commencement of construc-
tion. The owner or his representative, the agency representatives, the civil engineer, Ninyo &
Moore, and the contractor should be in attendance to discuss the plans, the project, and the
proposed construction schedule.
8.7. Plan Review and Construction Observation
The conclusions and recommendations presented in this report are based on analysis of ob-
served conditions. If conditions are found to vary from those described in this report,
Ninyo & Moore should be notified, and additional recommendations will be provided upon
request. Ninyo & Moore should review the project drawings and specifications prior to the
commencement of construction. Ninyo & Moore should perform the needed observation and
testing services during construction operations.
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The recommendations provided in this report are based on the assumption that Ninyo &
Moore will provide additional geotechnical evaluations during design of the project and ge-
otechnical observation and testing services during construction. In the event that it is
decided not to utilize the services of Ninyo & Moore during construction, we request that
the selected consultant provide the client with a letter (with a copy to Ninyo & Moore) indi-
cating that they fully understand Ninyo & Moore’s recommendations, and that they are in
full agreement with the design parameters and recommendations contained in this report.
Construction of proposed improvements should be performed by qualified subcontractors
utilizing appropriate techniques and construction materials.
9. LIMITATIONS
The field evaluation, laboratory testing, and geotechnical analyses presented in this geotechnical
report have been conducted in general accordance with current practice and the standard of care
exercised by geotechnical consultants performing similar tasks in the project area. No warranty,
expressed or implied, is made regarding the conclusions, recommendations, and opinions pre-
sented in this report. There is no evaluation detailed enough to reveal every subsurface condition.
Variations may exist and conditions not observed or described in this report may be encountered
during construction. Uncertainties relative to subsurface conditions can be reduced through addi-
tional subsurface exploration. Additional subsurface evaluation will be performed upon request.
Please also note that our evaluation was limited to assessment of the geotechnical aspects of the
project, and did not include evaluation of structural issues, environmental concerns, or the pres-
ence of hazardous materials.
This document is intended to be used only in its entirety. No portion of the document, by itself, is
designed to completely represent any aspect of the project described herein. Ninyo & Moore
should be contacted if the reader requires additional information or has questions regarding the
content, interpretations presented, or completeness of this document.
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This report is intended for design purposes only. It does not provide sufficient data to prepare an
accurate bid by contractors. It is suggested that the bidders and their geotechnical consultant per-
form an independent evaluation of the subsurface conditions in the project areas. The independent
evaluations may include, but not be limited to, review of other geotechnical reports prepared for
the adjacent areas, site reconnaissance, and additional exploration and laboratory testing.
Our conclusions, recommendations, and opinions are based on an analysis of the observed site
conditions. If geotechnical conditions different from those described in this report are encountered,
our office should be notified and additional recommendations, if warranted, will be provided upon
request. It should be understood that the conditions of a site could change with time as a result of
natural processes or the activities of man at the subject site or nearby sites. In addition, changes to
the applicable laws, regulations, codes, and standards of practice may occur due to government ac-
tion or the broadening of knowledge. The findings of this report may, therefore, be invalidated over
time, in part or in whole, by changes over which Ninyo & Moore has no control.
This report is intended exclusively for use by the client. Any use or reuse of the findings, conclu-
sions, and/or recommendations of this report by parties other than the client is undertaken at said
parties’ sole risk.
Recycled Water Phase III, Pipeline Segment 9 Project June 14, 2016
Carlsbad, California Project No. 108153001
108153001 R.doc 16
10. REFERENCES
American Concrete Institute, 2011, ACI 318 Building Code Requirements for Structural Con-
crete (ACI 318) and Commentary (ACI 318R).
American Society of Civil Engineers (ASCE), 2010, Minimum Design Loads for Buildings and
Other Structures, ASCE 7-10.
California Building Standards Commission (CBSC), 2013, California Building Code (CBC), Ti-
tle 24, Part 2, Volumes 1 and 2: dated June.
California Department of Conservation Division of Mines and Geology (CDMG), 1998, Maps of
Known Active Fault Near-Source Zones in California and Adjacent Portions of Nevada:
dated February.
California Department of Transportation (Caltrans), 2012, Corrosion Guidelines, Version 2.0,
Division of Engineering Services, Materials Engineering and Testing Services, Corrosion
and Structural Concrete Field Investigation Branch: dated November.
Cao, T., Bryant, W. A., Rowshandel, B., Branum, D., and Willis, C. J., 2003, The Revised 2002
California Probabilistic Seismic Hazards Maps: California Geological Survey: dated June.
City of Carlsbad, 2016a, Engineering Standards, Volume 2, Potable and Recycled Water Standards.
City of Carlsbad, 2016b, Engineering Standards, Volume 3, Standard Drawings and Specifications.
Geotracker, 2016, http://geotracker.swrcb.ca.gov/: accessed in May.
Google, Inc., 2016, www.googleearth.com: accessed in May.
Harden, D.R., 2004, California Geology, 2nd Edition: Prentice Hall, Inc.
Hartley, J.D., and Duncan, J.M., 1987, E’ and Its Variation with Depth: American Society of Civil
Engineers (ASCE), Journal of Transportation Engineering, Vol. 113, No. 5: dated September.
Jennings, C.W., 2010, Fault Activity Map of California and Adjacent Areas: California Geologi-
cal Survey, California Geologic Data Map Series, Map No. 6, Scale 1:750,000.
Kennedy, M.P., and Tan, S.S., 2007, Geologic Map of the Oceanside 30’ x 60’ Quadrangle, Califor-
nia, Scale 1:100,000.
Ninyo & Moore, In-House Proprietary Data.
Ninyo & Moore, 2016, Revised Proposal for Geotechnical Evaluation, OMWD Recycled Water
Pipeline, Segment 9, Carlsbad, California, Proposal No P02-00429: dated January 4.
Norris, R. M. and Webb, R. W., 1990, Geology of California, Second Edition: John Wiley & Sons, Inc.
Public Works Standards, Inc., 2015, “Greenbook,” Standard Specifications for Public Works Con-
struction.
Recycled Water Phase III, Pipeline Segment 9 Project June 14, 2016
Carlsbad, California Project No. 108153001
108153001 R.doc 17
Tan, S.S., 1995, Landslide Hazards in the Northern Part of the San Diego Metropolitan Area.
Treiman, J.A., 1993, The Rose Canyon Fault Zone, Southern California: California Geological
Survey, Open File Report 93-02.
United States Department of the Interior, Bureau of Reclamation, 1998, Engineering Geology
Field Manual.
United States Geological Survey, 2015, Encinitas Quadrangle, California, San Diego County,
7.5-Minute Series (Topographic): Scale 1:24,000.
United States Geological Survey, 2016, Seismic Design Maps Application,
http://earthquake.usgs.gov/designmaps/us/application.php: accessed in May.
AERIAL PHOTOGRAPHS
Source Date Flight Numbers Scale
United States Department of
Agriculture 4-11-53 AXN-8M 97 and 98 1:20,000
Navigator CrNOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE
1_108153001_SL_93.mxd AOB88
5
15
805805
215215
MAP INDEX
San DiegoCounty
0 1,500 3,000750
SCALE IN FEET
RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
SITE LOCATION FIGURE
1PROJECT NO.DATE
108153001 6/16
SOURCE: USGS, FAO, NPS, EPA, ESRI, DELORME, TANA, OTHER SUPPLIERS
LEGEND
SITE LOCATION
B-3TD=16.5
B-2
TD=15.9
B-1
TD=16.5
5
B-4
TD=16.5
WI N D RO S E CIRCLENAVIGATOR CIRCLECARL
SBAD BOUL
EVARDA
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IN
A
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PO I NS E T T I A L AN E
P
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D
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IV
E
P O N T O R D
NOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE
LEGEND
SITE LOCATION
0 800 1,600400
SCALE IN FEET
BORING LOCATIONS FIGURE
2PROJECT NO.DATE
2_108153001_BL_93.mxd AOBB-4
TD=16.5
SOURCE: GOOGLE EARTH, 2016.
BORING
TD=TOTAL DEPTH IN FEET
RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA1081530016/16
M E X I C OUSAPacific O c e a n
SAN JACINTO
ELSINORE
IM
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WHITTIER SAN ANDREAS
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SAN CLEMENTE
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OFFSHORE ZONE
OF DEFORMATIONGARLOCKWHITE WOLFCLEARWATERS
A
N GABRIEL
SIERRA MADRE
BANNING
MISSION CREEK
BLA
CK
W
ATE
RHARPER
LOCKHART
LEN
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CAMP ROCK
CALIC
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PIS
GAHBULLION MO
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MIRAGE VALLEY
NORTHHELENDALE
FRONTAL
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S A N J O S ECUCAMON G A
MALIBU COAS T SA N T A MONICA
SANCAYETANO
SANTASUSANASIMI-S A N T A
R O S A
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S A W P ITCAN Y O N
SUPERSTITION HILLS
NEVADA
CALIFORNIA
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NYONSan Bernardino County
Kern County
Riverside CountySan Diego County Imperial County
Los Angeles County
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Orange County
Riverside CountySan Bernardino CountyL
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y Kern CountyIndioIrvine
Pomona
Mojave
Anaheim
Barstow
Temecula
Palmdale
El CentroSanDiego
Escondido
Oceanside
SantaAna
Riverside
Tehachapi
Long Beach
Wrightwood
ChulaVista
Los Angeles
Victorville
SanClemente
PalmSprings
Big Bear CityThousandOaksSanBernardino
LakeArrowhead
Twentynine Palms
Baker
DesertCenter
CALIFOR NIA
0 30 60
SCALE IN MILES
LEGEND
HOLOCENE ACTIVE
CALIFORNIA FAULT ACTIVITY
HISTORICALLY ACTIVE
LATE QUATERNARY (POTENTIALLY ACTIVE)
STATE/COUNTY BOUNDARY
QUATERNARY (POTENTIALLY ACTIVE)
SITE
3_108153001_F_93.mxd AOBNOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE.
FAULT LOCATIONS FIGURE
3PROJECT NO.DATE
SOURCE: JENNINGS, C.W., AND BRYANT, W.A., 2010, FAULT ACTIVITY MAP OF CALIFORNIA, CALIFORNIA GEOLOGICAL SURVEY.
RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA1081530016/16
SOURCE: KENNEDY, M.P., ET AL, 2007, GEOLOGIC MAP OF THE OCEANSIDE 30' X 60'QUADRANGLE, CALIFORNIA
GEOLOGY FIGURE
4PROJECT NO.DATE
4_108153001_G_93.mxd AOBDELMAR FORMATION
TORREY SANDSTONE
LEGEND
VERY OLD PARALIC DEPOSITS, UNIT 10-11Qvop10-11
YOUNG ALLUVIAL FLOODPLAIN DEPOSITSQya
Td
0 2,000 4,000
SCALE IN FEET
Qvop2-4
VERY OLD PARALIC DEPOSITS, UNIT 13Qvop13
UD
FAULT - SOLID WHERE ACCURATELYLOCATED, DASHED WHERE APPROXIMATE, DOTTED WHERE CONCEALED. ARROW AND NUMBER INDICATE DIRECTION AND ANGLE OF DIP OF FAULT PLANE
5
OLD PARALIC DEPOSITS, UNIT 2-4Qop2-4
OLD PARALIC DEPOSITS, UNIT 6-7Qop6-7
Tt
STRIKE AND DIP OF BEDS, INCLINED
RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA1081530016/16
Qpe
Qvop10-11
Tsa
Q ya
LANDSLIDE DEPOISTS, UNDIVIDEDQls
PARALIC ESTUARINE DEPOSITSQpe
SANTIAGO FORMATIONTsa
SITE LOCATION
Recycled Water Phase III, Pipeline Segment 9 Project June 14, 2016
Carlsbad, California Project No. 108153001
108153001 R.doc
APPENDIX A
BORING LOGS
Field Procedure for the Collection of Disturbed Samples
Disturbed soil samples were obtained in the field using the following method.
Bulk Samples
Bulk samples of representative earth materials were obtained from the cuttings of the explora-
tory borings. The samples were bagged and transported to the laboratory for testing.
Field Procedure for the Collection of Relatively Undisturbed Samples
Relatively undisturbed soil samples were obtained in the field using a modified split-barrel drive
sampler. The sampler, with an external diameter of 3.0 inches, was lined with 1-inch long, thin
brass rings with inside diameters of approximately 2.4 inches. The sample barrel was driven into
the ground with the weight of a 140-pound hammer, in general accordance with ASTM D 3550.
The driving weight was permitted to fall freely. The approximate length of the fall, the weight of
the hammer, and the number of blows per foot of driving are presented on the boring logs as an
index to the relative resistance of the materials sampled. The samples were removed from the
sample barrel in the brass rings, sealed, and transported to the laboratory for testing.
0
5
10
15
20
XX/XX
SM
CL
Bulk sample.
Modified split-barrel drive sampler.
2-inch inner diameter split-barrel drive sampler.
No recovery with modified split-barrel drive sampler, or 2-inch inner diameter split-barrel
drive sampler.
Sample retained by others.
Standard Penetration Test (SPT).
No recovery with a SPT.
Shelby tube sample. Distance pushed in inches/length of sample recovered in inches.
No recovery with Shelby tube sampler.
Continuous Push Sample.
Seepage.
Groundwater encountered during drilling.
Groundwater measured after drilling.
MAJOR MATERIAL TYPE (SOIL):Solid line denotes unit change.
Dashed line denotes material change.
Attitudes: Strike/Dip
b: Bedding
c: Contact
j: Joint
f: Fracture
F: Fault
cs: Clay Seam
s: Shear
bss: Basal Slide Surface
sf: Shear Fracture
sz: Shear Zone
sbs: Shear Bedding Surface
The total depth line is a solid line that is drawn at the bottom of the boring.
BORING LOG
Explanation of Boring Log Symbols
PROJECT NO. DATE FIGUREDEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.BORING LOG EXPLANATION SHEET
SOIL CLASSIFICATION CHART PER ASTM D 2488
PRIMARY DIVISIONS SECONDARY DIVISIONS
GROUP SYMBOL GROUP NAME
COARSE-
GRAINED
SOILS
more than
50% retained
on No. 200
sieve
GRAVEL more than 50% of coarse
fraction retained on No. 4 sieve
CLEAN GRAVELless than 5% fines
GW well-graded GRAVEL
GP poorly graded GRAVEL
GRAVEL with DUAL
CLASSIFICATIONS
5% to 12% fines
GW-GM well-graded GRAVEL with silt
GP-GM poorly graded GRAVEL with silt
GW-GC well-graded GRAVEL with clay
GP-GC poorly graded GRAVEL with clay
GRAVEL with FINES
more than 12% fines
GM silty GRAVEL
GC clayey GRAVEL
GC-GM silty, clayey GRAVEL
SAND 50% or more
of coarse fraction
passes No. 4 sieve
CLEAN SAND
less than 5% fines
SW well-graded SAND
SP poorly graded SAND
SAND with
DUAL CLASSIFICATIONS 5% to 12% fines
SW-SM well-graded SAND with silt
SP-SM poorly graded SAND with silt
SW-SC well-graded SAND with clay
SP-SC poorly graded SAND with clay
SAND with FINES more than
12% fines
SM silty SAND
SC clayey SAND
SC-SM silty, clayey SAND
FINE-
GRAINED
SOILS
50% or
more passes
No. 200 sieve
SILT and
CLAY liquid limit less than 50%
INORGANIC
CL lean CLAY
ML SILT
CL-ML silty CLAY
ORGANIC OL (PI > 4)organic CLAY
OL (PI < 4)organic SILT
SILT and CLAY liquid limit 50% or more
INORGANIC CH fat CLAY
MH elastic SILT
ORGANIC
OH (plots on or
above “A”-line)organic CLAY
OH (plots below “A”-line)organic SILT
Highly Organic Soils PT Peat
USCS METHOD OF SOIL CLASSIFICATION
Explanation of USCS Method of Soil Classification
PROJECT NO.DATE FIGURE
APPARENT DENSITY - COARSE-GRAINED SOIL
APPARENT
DENSITY
SPOOLING CABLE OR CATHEAD AUTOMATIC TRIP HAMMER
SPT (blows/foot)
MODIFIED SPLIT BARREL (blows/foot)
SPT (blows/foot)
MODIFIED SPLIT BARREL (blows/foot)
Very Loose < 4 < 8 < 3 < 5
Loose 5 - 10 9 - 21 4 - 7 6 - 14
Medium Dense 11 - 30 22 - 63 8 - 20 15 - 42
Dense 31 - 50 64 - 105 21 - 33 43 - 70
Very Dense > 50 > 105 > 33 > 70
CONSISTENCY - FINE-GRAINED SOIL
CONSIS-TENCY
SPOOLING CABLE OR CATHEAD AUTOMATIC TRIP HAMMER
SPT (blows/foot)
MODIFIED SPLIT BARREL
(blows/foot)
SPT (blows/foot)
MODIFIED SPLIT BARREL (blows/foot)
Very Soft < 2 < 3 < 1 < 2
Soft 2 - 4 3 - 5 1 - 3 2 - 3
Firm 5 - 8 6 - 10 4 - 5 4 - 6
Stiff 9 - 15 11 - 20 6 - 10 7 - 13
Very Stiff 16 - 30 21 - 39 11 - 20 14 - 26
Hard > 30 > 39 > 20 > 26
LIQUID LIMIT (LL), %PLASTICITY INDEX (PI), %0 10
107
4
20
30
40
50
60
70
0 20 30 40 50 60 70 80 90 100
MH or OH
ML or OLCL - ML
PLASTICITY CHART
GRAIN SIZE
DESCRIPTION SIEVE SIZE GRAIN SIZE APPROXIMATE SIZE
Boulders > 12”> 12”Larger than basketball-sized
Cobbles 3 - 12”3 - 12”Fist-sized to
basketball-sized
Gravel
Coarse 3/4 - 3”3/4 - 3”Thumb-sized to
fist-sized
Fine #4 - 3/4”0.19 - 0.75”Pea-sized to thumb-sized
Sand
Coarse #10 - #4 0.079 - 0.19”Rock-salt-sized to pea-sized
Medium #40 - #10 0.017 - 0.079”Sugar-sized to rock-salt-sized
Fine #200 - #40 0.0029 -
0.017”
Flour-sized to
sugar-sized
Fines Passing #200 < 0.0029”Flour-sized and
smaller
CH or OH
CL or OL
0
10
20
30
40
45
51
84
5.8
4.7
106.7
100.8
SM
SM
ASPHALT CONCRETE:Approximately 6 inches thick.
BASE:Approximately 6 inches thick.
FILL:
Brown, moist, medium dense, silty fine to medium SAND; scattered gravel.
OLD PARALIC DEPOSITS:Dark yellowish brown, moist, medium dense, silty fine SAND; micaceous; cohesionless.
Yellowish brown.
Light brown.
Dense.
Total Depth = 16.5 feet.
Groundwater not encountered.
Backfilled and patched with perma patch shortly after drilling on 5/17/16.
Note: Groundwater, though not encountered at the time of drilling, may rise to a higher
level due to seasonal variations in precipitation and several other factors as discussed in
the report.
The ground elevation shown above is an estimation only. It is based on our interpretations
of published maps and other documents reviewed for the purposes of this evaluation. It is
not sufficiently accurate for preparing construction bids and design documents.
BORING LOG
RECYCLED WATER PHASE III PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
PROJECT NO.
108153001
DATE
6/16
FIGURE
A-1DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 5/17/16 BORING NO.B-1
GROUND ELEVATION 64' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter Hollow Stem Auger (A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY CAT LOGGED BY CAT REVIEWED BY TCS
1
0
10
20
30
40
44
88
50/4"
5.7
10.1
117.3
123.4
SM
SM
ASPHALT CONCRETE:Approximately 3 inches thick (no base).
FILL:Dark brown, moist, medium dense, silty fine SAND; scattered gravel.
Few pockets of clay.Scattered brick fragments.
OLD PARALIC DEPOSITS:Grayish brown, moist to wet, medium dense, silty fine to medium SAND; clayey; some
yellow staining.
Dense; gravelly.
Dark yellowish brown; fine to coarse sand; no clay.
Light gray; very dense; fine sand.
Total Depth = 15.9 feet.
Groundwater not encountered.
Backfilled and patched with perma patch shortly after drilling on 5/17/16.
Note: Groundwater, though not encountered at the time of drilling, may rise to a higher
level due to seasonal variations in precipitation and several other factors as discussed in
the report.
The ground elevation shown above is an estimation only. It is based on our interpretations
of published maps and other documents reviewed for the purposes of this evaluation. It is
not sufficiently accurate for preparing construction bids and design documents.
BORING LOG
RECYCLED WATER PHASE III PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
PROJECT NO.
108153001
DATE
6/16
FIGURE
A-2DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 5/17/16 BORING NO.B-2
GROUND ELEVATION 42' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter Hollow Stem Auger (A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY CAT LOGGED BY CAT REVIEWED BY TCS
1
0
10
20
30
40
90
56
66
4.0
3.5
115.1
106.1
SM
SM
ASPHALT CONCRETE:Approximately 3-1/2 inches thick.
BASE:Approximately 2 inches thick.
FILL:
Reddish brown, moist, medium dense, silty fine to medium SAND.
OLD PARALIC DEPOSITS:Reddish brown, moist, dense, silty fine SAND; scattered pinhole voids.
Yellowish brown; medium dense; fine to medium sand.
Light yellowish brown; fine sand.Fine to coarse sand with gravel up to 1/2 inch.
Total Depth = 16.5 feet.
Groundwater not encountered.
Backfilled and patched with perma patch shortly after drilling on 5/17/16.
Note: Groundwater, though not encountered at the time of drilling, may rise to a higher
level due to seasonal variations in precipitation and several other factors as discussed in
the report.
The ground elevation shown above is an estimation only. It is based on our interpretations
of published maps and other documents reviewed for the purposes of this evaluation. It is
not sufficiently accurate for preparing construction bids and design documents.
BORING LOG
RECYCLED WATER PHASE III PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
PROJECT NO.
108153001
DATE
6/16
FIGURE
A-3DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 5/17/16 BORING NO.B-3
GROUND ELEVATION 46' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter Hollow Stem Auger (A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY CAT LOGGED BY CAT REVIEWED BY TCS
1
0
10
20
30
40
27
54
57
7.3
8.5
97.7
119.7
SM
SM
ASPHALT CONCRETE:Approximately 4 inches thick.
BASE:Approximately 5 inches thick.
FILL:
Reddish brown, moist, medium dense, silty fine to medium SAND; few gravel.@ 2': Gray; fine to coarse sand.@ 2.5': Reddish brown; fine to medium sand.Brown; trace coarse sand and fine gravel.
OLD PARALIC DEPOSITS:Reddish brown, moist, medium dense, silty fine to medium SAND; trace clay.
Some light brown mottling.
Total Depth = 16.5 feet.
Groundwater not encountered.
Backfilled and patched with perma patch shortly after drilling on 5/17/16.
Note: Groundwater, though not encountered at the time of drilling, may rise to a higher
level due to seasonal variations in precipitation and several other factors as discussed in
the report.
The ground elevation shown above is an estimation only. It is based on our interpretations
of published maps and other documents reviewed for the purposes of this evaluation. It is
not sufficiently accurate for preparing construction bids and design documents.
BORING LOG
RECYCLED WATER PHASE III PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
PROJECT NO.
108153001
DATE
6/16
FIGURE
A-4DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 5/17/16 BORING NO.B-4
GROUND ELEVATION 99' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter Hollow Stem Auger (A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY CAT LOGGED BY CAT REVIEWED BY TCS
1
Recycled Water Phase III, Pipeline Segment 9 Project June 14, 2016
Carlsbad, California Project No. 108153001
108153001 R.doc
APPENDIX B
LABORATORY TESTING
Classification
Soils were visually and texturally classified in accordance with the Unified Soil Classification
System (USCS) in general accordance with ASTM D 2488. Soil classifications are indicated on
the logs of the exploratory borings in Appendix A.
In-Place Moisture and Density Tests
The moisture content and dry density of relatively undisturbed samples obtained from the ex-
ploratory borings were evaluated in general accordance with ASTM D 2937. The test results are
presented on the logs of the exploratory borings in Appendix A.
Gradation Analysis
Gradation analysis tests were performed on selected representative soil samples in general accord-
ance with ASTM D 422. The grain-size distribution curves are shown on Figures B-1 through B-3.
The test results were utilized in evaluating the soil classifications in accordance with the USCS.
Direct Shear Tests
Direct shear tests were performed on representative samples in general accordance with ASTM
D 3080 to evaluate the shear strength characteristics of the selected material. The samples were
inundated during shearing to represent adverse field conditions. The test results are shown on
Figures B-4 and B-5.
Soil Corrosivity Tests
Soil pH and electrical resistivity tests were performed on representative samples in general ac-
cordance with CT 643. The chloride contents of the selected samples were evaluated in general
accordance with CT 422. The sulfate contents of the selected samples were evaluated in general
accordance with CT 417. The test results are presented on Figure B-6.
Coarse Fine Coarse Medium SILT CLAY
3" 2"¾"½" ⅜"4 8 3050
PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422
USCS
--
D60
SM-- -- -- 12
Passing
No. 200
(%)
CcCu
B-1 4.0-8.0 -- -- -- --
GRAVEL SAND FINES
Symbol Plasticity
Index
Plastic
Limit
Liquid
Limit
1½" 1"
Depth
(ft)D30
Fine
Sample
Location
100
D10
16 200
108153001 6/16
B-1RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS
U.S. STANDARD SIEVE NUMBERS HYDROMETER
GRADATION TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_SIEVE B-1 @ 4.0-8.0.xls
Coarse Fine Coarse Fine Silt Clay
3" 1-1/2" 1" 3/4" 1/2" 3/8" 4 8 16 30 50 100 200
PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422
Symbol Plasticity
Index
Plastic
Limit
Liquid
Limit
Depth
(ft)CcCu USCSD60
Medium
GRAVEL SAND FINES
D30D10
Passing
No. 200
(%)
Sample
Location
B-2 2.0-5.0 -- -- -- -- -- -- -- -- 19 SM
RECYCLED WATER PHASE III B-2PIPELINE SEGMENT 9 PROJECT
108153001 6/16 CARLSBAD, CALIFORNIA
0
10
20
30
40
50
60
70
80
90
100
0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS
U.S. STANDARD SIEVE NUMBERS HYDROMETER
GRADATION TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_SIEVE B-2 @ 2.0-5.0.xls
Coarse Fine Coarse Medium SILT CLAY
3" 2"¾"½" ⅜"4 8 3050
PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 422
USCS
--
D60
SM-- -- -- 22
Passing
No. 200
(%)
CcCu
B-4 5.0-6.5 -- -- -- --
GRAVEL SAND FINES
Symbol Plasticity
Index
Plastic
Limit
Liquid
Limit
1½" 1"
Depth
(ft)D30
Fine
Sample
Location
100
D10
16 200
108153001 6/16
B-3RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
0.0
10.0
20.0
30.0
40.0
50.0
60.0
70.0
80.0
90.0
100.0
0.00010.0010.010.1110100PERCENT FINER BY WEIGHTGRAIN SIZE IN MILLIMETERS
U.S. STANDARD SIEVE NUMBERS HYDROMETER
GRADATION TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_SIEVE B-4 @ 5.0-6.5.xls
X
6/16
PIPELINE SEGMENT 9 PROJECT
RECYCLED WATER PHASE III
CARLSBAD, CALIFORNIA
Ultimate5.0-6.5B-1
B-4
PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080
Silty SAND
108153001
Cohesion, c
(psf)
Friction Angle,
(degrees)Soil Type
SM33
40
0
SM
Description Symbol
Sample
Location
0
Depth
(ft)
Shear
Strength
5.0-6.5Silty SAND B-1 Peak
0
1000
2000
3000
4000
0 1000 2000 3000 4000SHEAR STRESS (PSF)NORMAL STRESS (PSF)
DIRECT SHEAR TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_DIRECT SHEAR B-1 @ 5.0-6.5.xls
X
6/16
PIPELINE SEGMENT 9 PROJECT
RECYCLED WATER PHASE III
CARLSBAD, CALIFORNIA
Ultimate5.0-6.5B-3
B-5
PERFORMED IN GENERAL ACCORDANCE WITH ASTM D 3080
Silty SAND
108153001
Cohesion, c
(psf)
Friction Angle,
(degrees)Soil Type
SM32
38
0
SM
Description Symbol
Sample
Location
0
Depth
(ft)
Shear
Strength
5.0-6.5Silty SAND B-3 Peak
0
1000
2000
3000
4000
0 1000 2000 3000 4000SHEAR STRESS (PSF)NORMAL STRESS (PSF)
DIRECT SHEAR TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_DIRECT SHEAR B-3 @ 5.0-6.5.xls
1 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 643
2 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 417
3 PERFORMED IN GENERAL ACCORDANCE WITH CALIFORNIA TEST METHOD 422
108153001
140
90
65
18,000
2.0-5.0 3,300
5.0-10.0
B-3
B-4
CHLORIDE
CONTENT 3
(ppm)
pH 1SAMPLE DEPTH
(FT)
SAMPLE
LOCATION (Ohm-cm)
RESISTIVITY 1 SULFATE CONTENT 2
(%)(ppm)
B-1
5,900
4.0-8.0 7.1
7.0
6.9
6/16 B-6RECYCLED WATER PHASE III
PIPELINE SEGMENT 9 PROJECT
CARLSBAD, CALIFORNIA
0.009
0.005
20 0.002
90
50
CORROSIVITY TEST RESULTS
PROJECT NO. DATE
FIGURE
108153001_CORROSIVITY Page 1.xls