HomeMy WebLinkAbout5208; RECYCLED WATER PHASE III PIPELINE EXPANSION SEGMENTS 1A AND 7; GEOTECHNICAL EVALUATION; 2014-11-25
GEOTECHNICAL EVALUATION
CARLSBAD PHASE III
RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
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
November 25, 2014
Project No. 107814001
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
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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. Alluvium .............................................................................................................5
5.2.3. Santiago Formation.............................................................................................5
5.2.4. Granitic Rock......................................................................................................5
5.3. Groundwater.................................................................................................................6
6. GEOLOGIC HAZARDS..........................................................................................................6
6.1. Faulting and Seismicity................................................................................................6
6.1.1. Ground Surface Rupture .....................................................................................7
6.1.2. Strong Ground Motions ......................................................................................7
6.1.3. Liquefaction and Seismically Induced Settlement..............................................8
6.2. Landsliding...................................................................................................................8
7. CONCLUSIONS ......................................................................................................................8
8. RECOMMENDATIONS..........................................................................................................9
8.1. Earthwork ...................................................................................................................10
8.1.1. Site Preparation.................................................................................................10
8.1.2. Excavation Characteristics................................................................................10
8.1.3. Temporary Excavations and Shoring................................................................10
8.1.4. Excavation Bottom Stability.............................................................................12
8.1.5. Construction Dewatering ..................................................................................12
8.1.6. Pipe Bedding and Pipe Zone Backfill...............................................................13
8.1.7. Modulus of Soil Reaction (E')...........................................................................13
8.1.8. Trench Zone Backfill Materials........................................................................14
8.1.9. Fill Placement and Compaction........................................................................14
8.2. Trenchless Piping Installation.....................................................................................14
8.3. Lateral Pressures for Thrust Blocks and Jacking........................................................15
8.4. Pavement Reconstruction ...........................................................................................15
8.5. Corrosivity..................................................................................................................16
8.6. Concrete Placement....................................................................................................16
8.7. Pre-Construction Conference......................................................................................17
8.8. Plan Review and Construction Observation...............................................................17
9. LIMITATIONS.......................................................................................................................17
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10. REFERENCES.......................................................................................................................19
Figures
Figure 1 – Site Locations
Figure 2A – Boring Locations, Pipeline Expansion Segment 1A
Figure 2B – Boring Locations, Pipeline Expansion Segment 7
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 August 29, 2014 as revised by IEC, we
have performed a geotechnical evaluation for the proposed Carlsbad Phase III Recycled Water
Project Pipeline Expansion Segments 1A and 7 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
data, performance of a geologic reconnaissance, and engineering analysis with regard to the pro-
posed 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 encroachment permits from the City of Carlsbad.
Performing a subsurface exploration program consisting of excavating, logging, and sampling of
ten exploratory borings.
Performing geotechnical laboratory testing on representative soil samples to evaluate geo-
technical 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 recycled water piping system for the
City of Carlsbad. This project is separated into two distinct areas referenced as Pipeline Expan-
sion Segments 1A and 7. Pipeline Expansion Segment 1A includes the installation of 2,400 lineal
feet of 8-inch diameter PVC piping, 2,900 lineal of 6-inch diameter PVC piping, and 4,100 lineal
feet of 4-inch diameter PVC piping along with various laterals. This piping will be installed be-
neath the roadways for Corte Del Abeto, Corte Del Cedro, Corte De La Pina, Corte Del Nogal,
Las Palmas Drive, Yarrow Drive, and Cosmos Court. As part of the piping installation within this
segment, two locations will be installed using trenchless piping installation techniques to pass the
pipe under existing storm drain culverts. The anticipated invert depths of the piping at these un-
der crossings are anticipated to be approximately 15 feet. Surface elevations along Pipeline
Expansion Segment 1A range from a low of approximately 180 feet above mean sea level (MSL)
at the intersection between Corte Del Nogal and Camino Vida Roble to a high of approximately
260 feet above MSL at the north end of Yarrow Drive.
Pipeline Expansion Segment 7 includes the installation of 1,800 lineal feet of 8-inch diameter PVC
piping, 5,000 lineal of 6-inch diameter PVC piping, and 700 lineal feet of 4-inch diameter PVC
piping along with various laterals. This piping will be installed beneath the roadways for Andover
Avenue, Bridgeport Lane, Carlsbad Village Drive, Chatham Road, and Tamarack Avenue. Surface
elevations along Pipeline Expansion Segment 7 range from a low of approximately 200 feet above
MSL at the northern portion of the segment on Tamarack Avenue to a high of approximately
350 feet above MSL at the intersection between Carlsbad Village Drive and Glasgow Drive.
4. FIELD EXPLORATION AND LABORATORY TESTING
Our subsurface exploration was conducted on October 22 and 23, 2014 and consisted of drilling,
logging, and sampling of seven small-diameter exploratory borings (B-1 through B-10). The bor-
ings were drilled to depths up to approximately 18 feet using a truck-mounted drill rig equipped with
8-inch diameter, hollow-stem augers. Prior to drilling Borings B-2 through B-6, the existing AC sur-
faces were cored to provide access for the drilling operations. During the drilling operations, the
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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. Borings B-1 through B-4 were performed within the area
for Pipeline Expansion Segment 7. The other borings (B-5 through B-10) were performed within
the area for Pipeline Expansion Segment 1A. The approximate locations of the exploratory borings
are shown on Figure 2. Logs of the borings are included in Appendix A.
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 pre-
sented in Appendix B.
5. GEOLOGY AND SUBSURFACE CONDITIONS
Our findings regarding regional and site geology and groundwater conditions at the project site
are provided in the following sections.
5.1. Regional and Geologic Setting
The project area is situated in the Peninsular Ranges Geomorphic Province. This geomor-
phic 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
(Norris and Webb, 1990). The province varies in width from approximately 30 to 100 miles.
In general, the province consists of rugged mountains underlain by Jurassic metavolcanic
and metasedimentary rocks, and Cretaceous igneous rocks of the Southern California Batho-
lith. The portion of the province in San Diego County that includes the project area consists
generally of Quaternary and Tertiary age sedimentary rock.
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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 consid-
ered 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 Diego
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 approximately 6 miles
west of the project segments. Major tectonic activity associated with these faults within this
regional tectonic framework consists primarily of right-lateral, strike-slip movement.
5.2. Site Geology
Geologic units encountered during our reconnaissance and subsurface exploration in-
cluded fill, alluvium, and materials mapped as the Santiago Formation and granitic rock
(Kennedy and Tan, 2007). Generalized descriptions of the earth units encountered are
provided in the subsequent sections. Additional descriptions 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 our exploratory borings B-2 and B-4 within Pipeline Expansion
Segment 7 and in B-5 through B-10 within Pipeline Expansion Segment 1A. The fill ma-
terials were encountered beneath the pavement sections and extending to varying depths.
As encountered, the fill generally consisted of mottled gray and light brown to brown,
moist, medium dense to dense, silty sand and grayish brown, moist, soft to hard, sandy
clay and black, grayish green, and various shades of brown, moist, medium dense to
dense, clayey sand. Pieces of sandstone and claystone along with gravel, cobbles, and or-
ganic debris including wood pieces were observed within the encountered fill materials.
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5.2.2. Alluvium
Alluvium was encountered in our exploratory boring B-9 that was performed within the
area for the Pipeline Expansion Segment 1A. The alluvium in this boring was encountered
underlying the fill materials and extending to the total depth explored of approximately
18 feet for this boring. As encountered, the alluvium generally consisted of various shades
of brown, wet, stiff to very stiff, fine sandy clay and medium dense, clayey sand.
5.2.3. Santiago Formation
Materials of the Eocene-age Santiago Formation have been mapped (Kennedy and
Tan, 2007) and observed along several portions of both the pipeline segments. Within
the Pipeline Expansion Segment 1A, the materials of the Santiago Formation were en-
countered in our exploratory borings B-5, B-7, and B-10 underlying the existing fill
materials and extending to the total depths explored of these borings. Within the Pipe-
line Expansion Segment 7, the materials of the Santiago Formation were encountered in
our exploratory borings B-1 through B-3 beneath the pavement section (borings B-1 and
B-3) or underlying the shallow existing fill materials (boring B-2) and extending to the
total depths explored. As encountered, the Santiago Formation generally consisted of
various shades of brown, gray and green, moist, moderately to strongly cemented,
clayey to silty sandstone and claystone.
5.2.4. Granitic Rock
Materials mapped as granitic rock (Kennedy and Tan, 2007) were encountered in our
exploratory boring B-4 performed within the area for Pipeline Expansion Segment 7.
The granitic rock was encountered underlying the fill materials and extended to the total
depth explored of approximately 7 feet for this boring. As encountered, the granitic rock
consisted of whitish brown, dry, weathered granitic rock. Additionally, refusal to further
drilling was encountered within boring B-4.
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5.3. Groundwater
Groundwater was not encountered during our subsurface exploration. Our background re-
view did indicate that groundwater was encountered at elevations ranging from
approximately 154 to 175 feet above MSL at a site approximately 50 feet west of Pipeline
Expansion Segment 1A (Stantec, 2014). Also, our background review indicates a groundwa-
ter elevation of approximately 108 feet above MSL at a site approximately 1/2-mile north of
Expansion Segment 7 (Brown & Caldwell, 2008). However, seepage was encountered in our
boring B-9 at a depth of approximately 15 feet. 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
should be anticipated. Fluctuations in the groundwater level and perched conditions may oc-
cur due to variations in ground surface topography, subsurface geologic conditions and
structure, rainfall, irrigation, tidal fluctuations, and other factors.
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 site is not underlain by known active or potentially active 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 Can-
yon, 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.
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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 approximately 6 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
evaluate seismic loads for design of buildings and other structures. The MCER ground
motion response accelerations are based on the spectral response accelerations for
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 0.46g using the United States
Geological Survey (USGS, 2013) 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 0.45g using the USGS
(USGS, 2014) seismic design tool that yielded a mapped MCEG peak ground accelera-
tion of 0.42g for the site and a site coefficient (FPGA) of 1.083 for Site Class C.
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6.1.3. Liquefaction and Seismically Induced Settlement
Liquefaction of cohesionless soils can be caused by strong vibratory motion due to earth-
quakes. 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 formational and bedrock materials as well as the clayey
nature of the fills and alluvium underlying the segments, liquefaction and the resulting seis-
mically induced settlement are not design considerations.
6.2. Landsliding
Based on our review of published geologic maps (Kennedy and Tan, 2007) and aerial photo-
graphs, there is the presence of a potential landslide within the northern portion of Pipeline
Expansion Segment 7. Specifically, the portion of the segment along Tamarack Avenue,
north of its intersection with Chatham Road, is mapped within a potential landslide.
Although not specifically evaluated as part of this study, aerial photo review does not
indicate evidence of recent movement. Furthermore, based on the residential development of
the area along this portion of Pipeline Expansion Segment 7, especially the presence of
Hope Elementary School constructed in 1986-1987, it is reasonable to conclude that this is
not a design consideration for the proposed utility pipeline installation.
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, alluvium, materials of the Santiago For-
mation, and granitic rock.
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Although groundwater was not encountered, seepage was encountered at a depth of approxi-
mately 15 feet in Boring B-9. Additionally, perched water conditions may be present within
the project segment 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 wet soils proposed for reuse as backfill material.
The on-site fill and alluvium should be generally excavatable with conventional heavy-duty
earth moving construction equipment in generally good condition. However, difficult exca-
vating conditions should be anticipated due to concretions or strongly cemented zones
within the Santiago Formation and the presence of granitic rock or corestones. Drilling re-
fusal was encountered in our boring B-4 in granitic rock.
Materials derived from on-site excavations are generally considered suitable for reuse as back-
fill. However, on-site excavations may produce oversize materials. This material should be
broken up to be included or screened from materials to be reused as trench backfill and dis-
posed of off-site.
Wet and clayey soils were encountered during our subsurface exploration. Therefore, the
contractor should anticipate remediating soft and yielding trench bottom conditions that will
require stabilization efforts. Furthermore, additional processing of these materials (including
aeration) should be expected by the contractor.
Based on the soil corrosivity testing presented in Appendix B, test results indicate the project
alignment is considered corrosive based on ACI 318 and Caltrans corrosion criteria (2012).
The site soils are considered corrosive to ferrous metals and provide a potential for sulfate
attack on concrete structures.
No active faults are reported underlying or adjacent to the alignments. The active Rose Can-
yon fault has been mapped approximately 6 miles west of the segments.
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.
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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 alluvial soils are generally expected to be
rippable with heavy-duty trenching equipment.
During the performance of our subsurface exploration, drilling refusal was encountered
within boring B-4. Due to the potential presence of concretions and/or strongly ce-
mented zones within the Santiago Formation, as well as the presence of granitic rock in
some portions of the segments, the contractor should expect to encounter difficulty
when performing the trench excavations for the project.
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:
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Fill and Alluvium Type C
Santiago Formation and Granitic Rock Type B
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 regu-
lations. Temporary excavations should be constructed in accordance with OSHA
recommendations. For trench or other excavations, OSHA requirements regarding person-
nel 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 alluvium and 1:1
in materials of the Santiago Formation and granitic rock. Temporary excavations that en-
counter 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.
Settlement of the ground surface may occur behind the shoring wall during excavation.
The amount of settlement depends on the type of shoring system, the quality of contrac-
tor’s workmanship, and soil conditions. Settlement may cause distress to adjacent
structures, if present. To reduce the potential for distress to adjacent structures, we rec-
ommend that the shoring system be designed to limit the ground settlement behind the
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shoring to ½ inch or less. Possible causes of settlement that should be addressed include
vibration during installation of the sheet piling, excavation for construction, construction
vibrations, dewatering, and removal of the support system. We recommend that the poten-
tial settlement distress be evaluated carefully by the contractor prior to construction.
The contractor should retain a qualified and experienced engineer to design the shoring sys-
tem. The shoring parameters presented in this report are preliminary design criteria, and the
contractor should evaluate the adequacy of these parameters and make appropriate modifi-
cations for their design. We recommend that the contractor take appropriate measures to
protect workers. OSHA requirements pertaining to worker safety should be observed. We
further recommend that the construction methods provided herein be carefully evaluated by
a qualified specialty contractor prior to commencement of the construction.
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 suit-
able depths and replacing with a 6 to 12-inch layer of compacted ¾ to 1½-inch crushed
gravel, and encased in Mirafi® 600X geotextile, or approved equivalent. Recommenda-
tions for stabilizing excavation bottoms should be based on evaluation in the field by
the geotechnical consultant at the time of construction. However, as a general guideline,
overexcavation of approximately 2 to 3 feet may be appropriate to develop a stable ex-
cavation bottom, if groundwater is encountered.
8.1.5. Construction Dewatering
Seepage conditions were encountered in Boring B-9 at a depth of approximately
15 feet. Dewatering measures during excavation operations should be prepared by the
contractor’s engineer and reviewed by the design engineer. Considerations for con-
struction dewatering should include anticipated drawdown, piping of soils, volume of
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pumping, potential for settlement, and groundwater discharge. Disposal of groundwa-
ter should be performed in accordance with guidelines of the Regional Water Quality
Control Board (RWQCB).
8.1.6. Pipe Bedding and Pipe Zone Backfill
We recommend that pipes be supported on 6 inches or more of granular bedding mate-
rial. Pipe bedding and pipe zone backfill typically consists of graded aggregate with a
coefficient of uniformity of three or greater. Pipe bedding and pipe zone backfill should
have a Sand Equivalent (SE) of 30 or greater with no material larger than 1/2-inch (City
of Carlsbad, 2004a). These materials should be placed below, around the sides, and 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, 2004b).
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.
8.1.7. 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
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.
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8.1.8. 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 greater than approxi-
mately 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.
8.1.9. Fill Placement and Compaction
Fill and trench backfill should be compacted by mechanical methods in uniform 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 beneath pave-
ment 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 moisture content as
evaluated by the latest edition of ASTM D 1557. The optimum lift thickness of fill will de-
pend 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 fin-
ished grades are achieved. Special care should be taken to avoid pipe damage when
compacting trench backfill above the pipe.
8.2. Trenchless Piping Installation
We understand that trenchless piping installation methods such as microtunneling and/or
jack-and-bore methods may be used at two locations within Pipeline Expansion Seg-
ment 1A. Specifically, trenchless piping installation may used at the southern ends of Corte
Del Abeto and Yarrow Drive to pass under existing storm drain culverts. Entry and receiving
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 15
pits will be installed at each end of the trenchless piping installation areas. Based on infor-
mation provided by the client, we understand that the trenchless piping installation
operations may extend to invert depths of approximately 15 feet (below the existing ground
surface). Due to the depth of the pits and potential for seepage or perched water conditions
as encountered in our boring, the pits may require dewatering during excavation.
Although our borings encountered medium dense to stiff consistency, the contractor should
take appropriate measures to reduce the loss of soil material at the drilling or casing head.
Pipe friction can be reduced by over-drilling, excavating a slightly larger diameter than the
pipe size, and by using drilling mud or other lubricants. We recommend that an experienced
specialty contractor be used for the microtunnel or jack-and-bore operations.
Minor ground surface settlements may occur from the pipe jacking operations. However,
due to the diameter of the proposed pipeline, settlements are not anticipated to impact
surface improvements and underground utilities, provided an experienced contractor per-
forms the work.
8.3. 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.
8.4. Pavement Reconstruction
Trench excavations in existing pavement areas may involve replacement of pavements at the com-
pletion of work. In general, pavement repair should be one inch thicker than the existing pavement
section conform to the material thicknesses and compaction requirements of the adjacent pave-
ment section. Subgrade and aggregate base materials should be compacted to 95 percent relative
compaction as evaluated by ASTM D 1557. Asphalt concrete (AC) should be compacted to 95
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 16
percent relative compaction as evaluated by ASTM D1561 (Hveem density). Actual pavement re-
construction should conform to the requirements of the city/agency of jurisdiction.
8.5. 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 content. 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 test-
ing was performed in general accordance with CT 417. The laboratory test results are presented in
Appendix B.
The pH of the tested samples were from 5.1 to 6.9. The electrical resistivities of the tested sam-
ples ranged from approximately 700 to 1,200 ohm-centimeters. The chloride contents of the
tested samples ranged from approximately 110 to 950 ppm. The sulfate contents of the tested
samples were from approximately 0.015 to 1 percent by weight (i.e., 150 to 10,000 ppm). Based
on the laboratory test results, ACI 318, and Caltrans (2012) corrosion criteria, the project align-
ment would 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.
8.6. 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 at a sulfate content to
be approximately 1.000 percent, which is considered to represent a severe potential for sul-
fate attack (ACI, 318). Due to the potential for variability of soils, we recommend using
Type IV cement for concrete structures in contact with soil Per ACI 318, the concrete should
possess a compressive strength of 4,500 pounds per square inch (psi) and a water-to-cement
ratio of no more than 0.45.
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 17
8.7. Pre-Construction Conference
We recommend that a pre-construction meeting be held prior to commencement of grading.
The owner or his representative, the agency representatives, the architect, the civil engineer,
Ninyo & Moore, and the contractor should be in attendance to discuss the plans, the project,
and the proposed construction schedule.
8.8. 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 final project drawings and specifications prior to
the commencement of construction. Ninyo & Moore should perform the needed observation
and testing services during construction operations.
The recommendations provided in this report are based on the assumption that Ninyo &
Moore will provide additional geotechnical evaluations during final design of the project
and geotechnical 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-
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 18
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.
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.
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 19
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.
Brown & Caldwell, 2008, Report of 2nd Quarter 2008 Groundwater and Status of Site Remedia-
tion Activities Hanson America - Carlsbad Facility, 3701 Haymar Drive, Carlsbad,
California, DEH Case Number H02509-001: dated August 1.
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, 2004a, Engineering Standards, Volume 2, Potable and Recycled Water Standards.
City of Carlsbad, 2004b, Engineering Standards, Volume 3, Standard Drawings and Specifications.
County of San Diego, 1974, Orthotopographic Survey Map, Sheet 366-1677, Scale 1”=2,400’.
County of San Diego, 1975, Orthotopographic Survey Map, Sheet 346-1683, Scale 1”=2,400’.
County of San Diego, 1975, Orthotopographic Survey Map, Sheet 350-1683, Scale 1”=2,400’.
County of San Diego, 1963, Topographic Survey Map, Sheet 346-1683, Scale 1”=2,400’.
County of San Diego, 1963, Topographic Survey Map, Sheet 350-1683, Scale 1”=2,400’.
Geotracker, 2014, http://geotracker.swrcb.ca.gov/.
Google, Inc., 2014, www.googleearth.com.
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.
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 R.doc 20
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, 2014, Proposal for Geotechnical Evaluation, Carlsbad Phase III Recycled water
Project, Pipeline Expansion Segments 1A and 7, Carlsbad, California, Proposal No
P-21593: dated August 29.
Norris, R. M. and Webb, R. W., 1990, Geology of California, Second Edition: John Wiley & Sons, Inc.
Public Works Standards, Inc., 2012, “Greenbook,” Standard Specifications for Public Works Con-
struction.
Stantec, 2014, Semi-Annual Status Report, Former ARCO Facility No. 5792, 1991 Palomar Air-
port Road, Carlsbad, California: dated April 30.
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, 1997, San Luis Rey Quadrangle, California, San Diego County,
7.5-Minute Series (Topographic): Scale 1:24,000.
United States Geological Survey, 2014, Seismic Design Maps Application,
http://earthquake.usgs.gov/designmaps/us/application.php: accessed November 11.
AERIAL PHOTOGRAPHS
Source Date Flight Numbers Scale
United States Department of
Agriculture 4-11-53 AXN-8M 71. 72,
103 and 104 1:20,000
NOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE
1_107814001_SL.mxd AOBPIPELINE EXPANSIONSEGMENT 7
88
55
15
805805
215215
MAP INDEX
San DiegoCounty
0 3,000 6,0001,500
SCALE IN FEET
SITE LOCATIONS FIGURE
1PROJECT NO.DATE
SOURCE: USGS, FAO, NPS, EPA, ESRI, DeLorme, TANA, other suppliers
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA10781400111/14
PIPELINE EXPANSIONSEGMENT 1A
CAMINO
VI
DA
R
OBL
E YARROW DRIVEPALOMAR AIRPORT ROADLAS PALMAS DRIVEEL CAMINO REALCORTE DEL NOGALC
O
R
T
E
D
E
L
A
B
E
T
O CORTE DEL CEDROCORTE DE LA PINA
COSMOS COURT
OLEA LN
NOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE
0 500 1,000250
SCALE IN FEET
BORING LOCATIONS PIPELINE EXPANSION SEGMENT 1A FIGURE
2APROJECT NO.DATE
2A_107632001_SP.mxd AOBSOURCE: 2012 SAN DIEGO IMAGERY ACQUISITION PARTNERSHIP (FLIGHT DATES: MAY 20 - JUNE 6, 2012)
107814001 11/14
LEGEND
PIPELINE EXPANSION SEGMENT 1A
BORING
TD=TOTAL DEPTH IN FEETB-10
TD=15.9'
B-5
TD=15.5'
B-6
TD=18.0'
B-7
TD=16.0'
B-8
TD=16.5'
B-9
TD=18.0'
B-10
TD=15.9'
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA
HARWICH D
RI
VE
ANDOVER AVEN
U
E
BRI
D
G
E
P
O
R
T
L
A
N
E
CARLSBAD VILLA
G
E
D
RI
V
E GLASGOW
DR
IVE
CHATHAM ROAD
CHESHIRE AVENU
E
SANFORD LANETAMARACK AVENUEBE
N
N
I
N
G
T
O
N
C
O
U
R
T
TAMARACK AVENUENOTE: DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE
0 500 1,000250
SCALE IN FEET
BORING LOCATIONSPIPELINE EXPANSION SEGMENT 7 FIGURE
2BPROJECT NO.DATE
2B_107814001_BL.mxd AOBSOURCE: 2012 SAN DIEGO IMAGERY ACQUISITION PARTNERSHIP (FLIGHT DATES: MAY 20 - JUNE 6, 2012)
107814001 11/14
LEGEND
PIPELINE EXPANSION SEGMENT 7
BORING
TD=TOTAL DEPTH IN FEET
B-1
TD=15.2'
B-2
TD=16.5'
B-3
TD=15.5'
B-4
TD=7.0'
B-4
TD=7.0'
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA
M E X I C OUSAP a c i f i c O c e a n
SAN JACINTO
ELSINORE
IM
P
E
RIA
L
WHITTIER SAN ANDREAS
NEW
PORT-INGLEWOOD
C
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A
D
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S
A
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T
R
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SAN CLEMENTE
S
A
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A C
RUZ-SANTA CATALINA RIDGE
P
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F
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OF
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F
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NGARLOCKWHITE WOLFCLEARWATERS
A
N GABRIEL
SIERRA MADRE
BANNING
MISSION CREEK
BLA
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K
W
A
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RHARPER
LOCKHART
LEN
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CAMP ROCK
CALIC
O LUDLOW
PIS
GAHBULLION M
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EM
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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
N O R T H R ID G E
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S A W P ITCAN Y O N
SUPERSTITION HILLS
NEVADA
CALIFORNIA
R
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YONSan Bernardino County
Kern County
Riverside CountySan Diego County Imperial County
Los Angeles County
V
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o
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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
CALIFORNIA
0 30 60
SCALE IN MILES
LEGEND
HOLOCENE ACTIVE
CALIFORNIA FAULT ACTIVITY
HISTORICALLY ACTIVE
LATE QUATERNARY (POTENTIALLY ACTIVE)
STATE/COUNTY BOUNDARY
QUATERNARY (POTENTIALLY ACTIVE)
SITES
3_107814001_F.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.
107814001 11/14
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA
NOTES: ALL DIRECTIONS, DIMENSIONS AND LOCATIONS ARE APPROXIMATE 0 2,900 5,800
SCALE IN FEET
GEOLOGY FIGURE
4PROJECT NO.DATE4_107814001_G.mxd AOBSOURCE: KENNEDY, M.P., AND TAN, S.S., 2007, GEOLOGIC MAP OF THE OCEANSIDE 30' X 60' QUADRANGLE, CALIFORNIA
PIPELINE EXPANSIONSEGMENT 7
PIPELINE EXPANSIONSEGMENT 1A
107814001 11/14
METASEDIMENTARY AND METAVOLCANICROCKS UNDIVIDED
U
D
FAULT - SOLID WHERE ACCURATELY
LOCATED, DASHED WHERE APPROXIMATE, DOTTED WHERE CONCEALED. ARROW AND NUMBER INDICATE DIRECTION AND ANGLE OF DIP OF FAULT PLANE
LEGEND
65
LANDSLIDE DEPOSITS
MZu
OLD ALLUVIAL FLOOD PLAIN DEPOSITS
Qls
OLD PARALIC DEPOSITS, UNIT 2-4Qop2-4
VERY OLD PARALIC DEPOSITS, UNIT 10-11Qvop10-11
POINT LOMA FORMATIONKp
LUSARDI FORMATIONKl
ALLUVIAL FLOOD PLAN DEPOSITSQa
Qoa
SANTIAGO FORMATIONTsa
Kt TONALITE
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA
Qvop10-11
Qls
Qls
Qls
pP
D
H
CONSTRUCTION MATERIALS ARE NOT INCLUDED
5. SURCHARGES FROM EXCAVATED SOIL OR
4. ASSUMES GROUNDWATER IS NOT PRESENT
3. PASSIVE LATERAL EARTH PRESSURE, P
P = 350 D psf
2.
P = 120 psf
CONSTRUCTION TRAFFIC INDUCED SURCHARGE PRESSURE, P
1.
P = 26 H psf
APPARENT LATERAL EARTH PRESSURE, P
NOTES:
Pa Ps
a
a
s
s
p
p
6. H AND D ARE IN FEET
+
FIGURE
5PROJECT NO.
107814001
DATE
11/14
LATERAL EARTH PRESSURES FOR
BRACED EXCAVATION
SHORING
BRACES
5 107814001 d-beg.dwgCARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA
NOTES:
GROUNDWATER BELOW BLOCK
GROUNDWATER ABOVE BLOCK2.
1.
P = 180p (D -d )2 2 lb/ft
THRUST
BLOCK
d (VARIES)
P
Pp
p
D (VARIES)
3.ASSUMES BACKFILL IS GRANULAR MATERIAL
4.ASSUMES THRUST BLOCK IS ADJACENT TO COMPETENT MATERIAL
FIGURE
6PROJECT NO.DATE
THRUST BLOCK LATERAL EARTH PRESSURE DIAGRAM
1
Pp2
pP = 1.5 ( D - d )[ 124.8h + 57.6 ( D+d )]
GROUNDWATER TABLE6.
D, d AND h ARE IN FEET5.
h
lb/ft
6 107814001 d-tb.dwg107814001
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7
CARLSBAD, CALIFORNIA11/14
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 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 methods.
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.
The Standard Penetration Test (SPT) Sampler
Disturbed drive samples of earth materials were obtained by means of a Standard Penetra-
tion Test sampler. The sampler is composed of a split barrel with an external diameter of 2
inches and an unlined internal diameter of 1-3/8 inches. The sampler was driven into the
ground 12 to 18 inches with a 140-pound hammer free-falling from a height of 30 inches in
general accordance with ASTM D 1586. The blow counts were recorded for every 6 inches
of penetration; the blow counts reported on the logs are those for the last 12 inches of pene-
tration. Soil samples were observed and removed from the sampler, bagged, sealed 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
TYPICAL NAMES
GW Well graded gravels or gravel-sand mixtures, little or
no fines
GP Poorly graded gravels or gravel-sand mixtures, little
or no fines
GM Silty gravels, gravel-sand-silt mixtures
GC Clayey gravels, gravel-sand-clay mixtures
SW Well graded sands or gravelly sands, little or no fines
SP Poorly graded sands or gravelly sands, little or no
fines
SM Silty sands, sand-silt mixtures
SC Clayey sands, sand-clay mixtures
ML Inorganic silts and very fine sands, rock flour, silty or
clayey fine sands or clayey silts with slight plasticity
CL Inorganic clays of low to medium plasticity, gravelly
clays, sandy clays, silty clays, lean clays
OL Organic silts and organic silty clays of low plasticity
MH Inorganic silts, micaceous or diatomaceous fine sandy
or silty soils, elastic silts
CH Inorganic clays of high plasticity, fat clays
OH Organic clays of medium to high plasticity, organic
silty clays, organic silts
Pt Peat and other highly organic soils
U.S. Standard
Sieve Size
Grain Size in
Millimeters
BOULDERS Above 12" Above 305
COBBLES 12" to 3" 306 to 76.2
GRAVEL 3" to No. 4 76.2 to 4.76
Coarse 3" to 3/4" 76.2 to 19.1
Fine 3/4" to No. 4 19.1 to 4.76
SAND No. 4 to No. 200 4.76 to 0.075
Coarse No. 4 to No. 10 4.76 to 2.00
Medium No. 10 to No. 40 2.00 to 0.420
Fine No. 40 to No. 200 0.420 to 0.075
SILT & CLAY Below No. 200 Below 0.075
SYMBOL
U.S.C.S. METHOD OF SOIL CLASSIFICATION
FINE-GRAINED SOILS(More than 1/2 of soil < No. 200 sieve size)U.S.C.S. METHOD OF SOIL CLASSIFICATIONCOARSE-GRAINED SOILS(More than 1/2 of soil > No. 200 Sieve Size)MAJOR DIVISIONS
HIGHLY ORGANIC SOILS
GRAVELS
(More than 1/2 of coarse
fraction > No. 4 sieve size
SANDS
(More than 1/2 of coarse
fraction < No. 4 sieve size
SILTS & CLAYS
Liquid Limit <50
SILTS & CLAYS
Liquid Limit >50
GRAIN SIZE CHART
RANGE OF GRAIN
CLASSIFICATION
PLASTICITY CHART
CH
CL MH & OH
ML & OLCL - ML
0
10
20
30
40
50
60
70
0 102030405060708090100
LIQUID LIMIT (LL), %PLASTICITY INDEX (PI), %Updated Nov. 2011
0
10
20
30
40
50/7"
50/4"
50/3"
6.2 93.1
GM ASPHALT CONCRETE:Approximately 7 inches thick.
BASE:Brown, dry to moist, dense, silty GRAVEL with sand; approximately 9 inches thick.
SANTIAGO FORMATION:Grayish brown, dry to moist, moderately cemented, silty fine-grained SANDSTONE.
Moist.Total Depth = 15.2 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/22/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-1DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/22/14 BORING NO.B-1
GROUND ELEVATION 212' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
50/6"
65
48
15.8
14.9
110.0
113.7
GM
SM
ASPHALT CONCRETE:Approximately 5 inches thick.
BASE:Brown, dry to moist, dense, silty GRAVEL with sand; approximately 9 inches thick.
FILL:Mottled gray and light brown, moist, medium dense to dense, silty fine SAND; scattered
silty sandstone pieces; scattered clay pieces.
SANTIAGO FORMATION:Whitish brown, moist, moderately cemented, clayey fine-grained SANDSTONE.
Grayish green.
Iron-oxide staining.
Whitish gray; moist.Total Depth = 16.5 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/22/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-2DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/22/14 BORING NO.B-2
GROUND ELEVATION 231' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
50/6"
50/6"
50/6"
11.6 105.8
GM ASPHALT CONCRETE:Approximately 5 inches thick.
BASE:Brown, dry to moist, dense, silty GRAVEL with sand; approximately 8 inches thick.
SANTIAGO FORMATION:Whitish brown to gray, moist, moderately cemented, silty fine-grained SANDSTONE.
Total Depth = 15.5 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/22/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-3DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/22/14 BORING NO.B-3
GROUND ELEVATION 270' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
GM
CL
ASPHALT CONCRETE:Approximately 5 inches thick.
BASE:Grayish brown, moist, dense, silty GRAVEL with sand; approximately 19 inches thick.
FILL:Mottled brown and gray, moist, firm, sandy CLAY; scattered gravel and cobbles.
GRANITIC ROCK:Whitish brown, dry, weathered GRANITIC ROCK. (Refusal on granitic rock at 7 feet.)
Total Depth = 7 feet. (Refusal)
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/22/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-4DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/22/14 BORING NO.B-4
GROUND ELEVATION 333' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
67
50/4"
50/6"
10.9 109.2
SM
CL
ASPHALT CONCRETE:Approximately 6 inches thick.
FILL:Brown, moist, dense, silty fine to coarse SAND.Brownish gray, moist, soft to firm, fine sandy CLAY; micaceous.Greenish brown.
SANTIAGO FORMATION:Grayish brown, moist, moderately cemented, clayey fine-grained SANDSTONE.
Iron-oxide staining.
Total Depth = 15.5 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-5DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-5
GROUND ELEVATION 236' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
24
27
16
19
26.7
25.9
94.2
90.9
SM
CL
SC
CL
SC
ASPHALT CONCRETE:Approximately 6 inches thick.
FILL:Brown, moist, dense, silty fine to coarse SAND; micaceous.Grayish brown, moist, firm, fine to coarse sandy CLAY; scattered gravel.
Black, moist, dense, clayey fine SAND; scattered organics (wood debris); organic odor.
Mottled greenish gray and brown, moist, very stiff, fine to medium sandy CLAY.
Mottled brown and grayish green, moist, medium dense, clayey fine SAND.
Total Depth = 18 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-6DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-6
GROUND ELEVATION 201' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
50/5"
50
50/6"
16.1 110.2
SM
SC
ASPHALT CONCRETE:Approximately 6 inches thick.
FILL:Brown, moist, dense, silty fine to coarse SAND; micaceous.Light brown, moist, medium dense, clayey fine SAND.
SANTIAGO FORMATION:Light grayish brown, moist, moderately to strongly cemented, SANDSTONE.
Iron-oxide staining.
Brownish.
Mottled yellow and brown.Total Depth = 16 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-7DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-7
GROUND ELEVATION 215' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
76
54
87
10.9 107.3
SM
SC
CL
ASPHALT CONCRETE:Approximately 6 inches thick.
FILL:Brown, moist, dense, silty fine to coarse SAND; micaceous.Light brown, moist, dense, clayey fine SAND; scattered sandstone pieces; scattered iron-
oxide staining.
Grayish brown, moist, very stiff, fine sandy CLAY; iron-oxide staining.
Total Depth = 16.5 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-8DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-8
GROUND ELEVATION 247' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
29
9
21
17
21.0
24.0
100.3
98.5
SM
SC
CL
CL
SC
CL
ASPHALT CONCRETE:Approximately 7 inches thick.
FILL:Brown, dry to moist, dense, silty fine to coarse SAND; micaceous.Light brown, moist, medium dense, clayey fine SAND; scattered sandstone pieces.Mottled brown and greenish gray, moist, soft to firm, fine to medium sandy CLAY.
Hard.
Stiff.
ALLUVIUM:Dark brown, moist to wet, stiff, fine sandy CLAY; pinhole porosity.
Brown, wet, medium dense, clayey fine SAND.
Grayish brown, wet, stiff to very stiff, fine sandy CLAY.
Total Depth = 18 feet.
Seepage encountered at approximately 15 feet during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-9DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-9
GROUND ELEVATION 211' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
0
10
20
30
40
31
53
50/3"
18.2 106.9
SM
SC
CL
ASPHALT CONCRETE:Approximately 6 inches thick.
FILL:Brown, moist, dense, silty fine to coarse SAND; micaceous.Light brown, moist, dense, clayey fine SAND; scattered sandstone pieces; scattered iron-
oxide staining.Mottled brown and gray, moist, firm to stiff, fine to coarse sandy CLAY; iron-oxide
staining; scattered organics (leaves).
Hard.
SANTIAGO FORMATION:Dark gray, moist, moderately indurated, CLAYSTONE; some iron-oxide staining.
Total Depth = 15.9 feet.
Groundwater not encountered during drilling.
Backfilled and patched shortly after drilling on 10/23/14.
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
CARLSBAD PHASE III RECYCLED WATER PROJECT
PIPELINE EXPANSION SEGMENTS 1A AND 7, CARLSBAD, CALIFORNIA
PROJECT NO.
107814001
DATE
11/14
FIGURE
A-10DEPTH (feet)BulkSAMPLESDrivenBLOWS/FOOTMOISTURE (%)DRY DENSITY (PCF)SYMBOLCLASSIFICATIONU.S.C.S.DESCRIPTION/INTERPRETATION
DATE DRILLED 10/23/14 BORING NO.B-10
GROUND ELEVATION 244' (MSL)SHEET 1 OF
METHOD OF DRILLING 8" Diameter HSA (Ingersoll Rand A-300) (Scott's Drilling)
DRIVE WEIGHT 140 lbs. (Cathead)DROP 30"
SAMPLED BY AQP LOGGED BY AQP REVIEWED BY FOM
1
Carlsbad Phase III Recycled Water Project November 25, 2014
Pipeline Expansion Segments 1A and 7, Carlsbad, California Project No. 107814001
107814001 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 accor-
dance with ASTM D 422. The grain-size distribution curves are shown on Figures B-1 through B-4.
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-5 and B-6.
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-7.