HomeMy WebLinkAboutCDP 2018-0020; BUCCOLA ADDITION; GEOTECHNICAL INVESTIGATION; 2018-09-12
GEOTECHNICAL INVESTIGATION
PROPOSED BUCCOLA RESIDENCE ADDITION
5031 TIERRA DEL ORO
CARLSBAD, CALIFORNIA
Prepared for:
MR. ROBERT BUCCOLA
8140 SENTINEL STREET
FAIR OAKS, CALIFORNIA
Prepared by:
CONSTRUCTION TESTING & ENGINEERING, INC.
1441 MONTIEL ROAD, SUITE 115
ESCONDIDO, CALIFORNIA 92026
CTE JOB NO.: 10-14444G SEPTEMBER 12, 2018
TABLE OF CONTENTS
1.0 INTRODUCTION AND SCOPE OF SERVICES ................................................................... 1
1.1 Introduction ................................................................................................................... 1
1.2 Scope of Services .......................................................................................................... 1
2.0 SITE DESCRIPTION ............................................................................................................... 2
3.0 FIELD INVESTIGATION AND LABORATORY TESTING ................................................ 2
3.1 Field Investigation ........................................................................................................ 2
3.2 Laboratory Testing ........................................................................................................ 3
4.0 PERCOLATION TESTING ..................................................................................................... 3
4.1 Percolation Test Methods ............................................................................................. 4
4.2 Calculated Infiltrated Rate ........................................................................................................ 4
5.0 GEOLOGY ............................................................................................................................... 5
5.1 General Setting ............................................................................................................. 5
5.2 Geologic Conditions ..................................................................................................... 6
5.2.1 Quaternary Marine Beach Deposits ............................................................... 6
5.2.2 Quaternary Slopewash ................................................................................... 6
5.2.3 Residual Soil .................................................................................................. 7
5.2.4 Quaternary Old Paralic Deposits ................................................................... 7
5.2.5 Tertiary Santiago Formation .......................................................................... 7
5.3 Groundwater Conditions ............................................................................................... 8
5.4 Geologic Hazards .......................................................................................................... 8
5.4.1 Surface Fault Rupture .................................................................................... 9
5.4.2 Local and Regional Faulting .......................................................................... 9
5.4.3 Liquefaction and Seismic Settlement Evaluation ........................................ 10
5.4.4 Tsunamis, Sea Surface Super Elevation and Seiche Evaluation ................. 10
5.4.5 Landsliding and Slope Stability ................................................................... 11
5.4.6 Compressible and Expansive Soils .............................................................. 13
5.4.7 Corrosive Soils ............................................................................................. 13
6.0 BLUFF EVALUATION ......................................................................................................... 14
6.1 Review of Historic Topography ................................................................................. 14
6.2 Review of Historic Photography ................................................................................. 16
6.2.1 Aerial Photographs ...................................................................................... 16
6.3 Bluff Profiles ............................................................................................................... 17
6.4 Seacliff Recession ....................................................................................................... 18
7.0 CONCLUSIONS AND RECOMMENDATIONS ................................................................. 20
7.1 General ........................................................................................................................ 20
7.2 Site Preparation ........................................................................................................... 21
7.3 Site Excavation ........................................................................................................... 22
7.4 Fill Placement and Compaction .................................................................................. 22
7.5 Fill Materials ............................................................................................................... 23
7.6 Temporary Construction Slopes ................................................................................. 24
7.7 Foundations and Slab Recommendations ................................................................... 24
7.7.1 Foundations .................................................................................................. 25
7.7.2 Foundation Settlement ................................................................................. 26
7.7.3 Foundation Setback ...................................................................................... 26
7.7.4 Interior Concrete Slabs ................................................................................ 26
7.8 Seismic Design Criteria .............................................................................................. 28
7.9 Lateral Resistance and Earth Pressures ...................................................................... 29
7.10 Exterior Flatwork ...................................................................................................... 31
7.11 Vehicular Pavement .................................................................................................. 32
7.12 Drainage .................................................................................................................... 33
7.13 Slopes ........................................................................................................................ 33
7.14 Controlled Low Strength Materials (CLSM) ............................................................ 34
7.15 Plan Review .............................................................................................................. 35
7.16 Construction Observation ......................................................................................... 35
8.0 LIMITATIONS OF INVESTIGATION ................................................................................. 36
FIGURES
FIGURE 1 SITE LOCATION MAP
FIGURE 2 GEOLOGIC/ EXPLORATION LOCATION MAP
FIGURE 2A CROSS SECTION A-A'
FIGURE 3 REGIONAL GEOLOGIC MAP
FIGURE 4 REGIONAL FAULT AND SEISMICITY MAP
FIGURE 5 RETAINING WALL DRAINAGE DETAIL
APPENDICES
APPENDIX A REFERENCES
APPENDIX B FIELD EXPLORATION METHODS AND BORING LOGS
APPENDIX C LABORATORY METHODS AND RESULTS
APPENDIX D STANDARD GRADING SPECIFICATIONS
APPENDIX E SLOPE/W OUTPUT
APPENDIX F PERCOLATION TO INFILTRATION CALCULATIONS AND
FIELD DATA
APPENDIX G I-8 WORKSHEET
APPENDIX H HISTORIC TOPOGRAPHIC MAPS
APPENDIX I HISTORIC OBLIQUE AERIAL PHOTOGRAPHS BY
CALIFORNIA COSTAL PROJECT
APPENDIX J HISTORIC AERIAL PHOTOGRAPHS
Geotechnical Investigation
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1.0 INTRODUCTION AND SCOPE OF SERVICES
1.1 Introduction
Construction Testing and Engineering, Inc. (CTE) has completed a geotechnical investigation and
report providing conclusions and recommendations for the proposed improvements at the subject
site in Carlsbad, California. It is understood that the proposed improvements are to consist of a
second-story addition to the existing residence with associated flatwork, utilities, landscaping and
other minor improvements. CTE has performed this work in general accordance with the terms of
proposal G-4454 dated July 20, 2018. Based on the investigation findings, geotechnical
recommendations for the proposed residential addition are presented herein.
1.2 Scope of Services
The scope of services provided included:
Review of readily available geologic and soils reports.
Coordination of USA utility mark-out and location.
Excavation of exploratory borings and soil sampling utilizing limited-access drilling equipment
consisting of a tripod drill rig and a manually operated auger.
Percolation testing in accordance with County of San Diego Department of Environmental
Health (DEH) procedures.
Laboratory testing of selected soil samples.
Description of the site geology and evaluation of potential geologic hazards.
Engineering and geologic analysis.
Preparation of this geotechnical report.
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2.0 SITE DESCRIPTION
The subject site is located at 5031 Tierra Del Oro in Carlsbad, California (Figure 1). The site is
bounded by existing residential properties to the north and south, by the Pacific Ocean to the west,
and by Tierra Del Oro to the east. The site layout is illustrated on Figure 2. The improvement area
is currently developed with a single-story residential structure (with a partially subterranean lower
floor), associated flatwork, landscaping, utilities, and other minor improvements. Based on
reconnaissance and review of topography, the site descends to the southwest with elevations ranging
from approximately 37 feet above mean sea level (msl) in the northeast adjacent to Tierra Del Oro to
sea level at the southwestern limit of the site. In the western portion of the site an approximately 15
feet high 1.4:1 (horizontal: vertical) slope descends to the southwest with stabilizing rip rap placed at
the toe of slope on the eastern limit of the beach.
3.0 FIELD INVESTIGATION AND LABORATORY TESTING
3.1 Field Investigation
CTE performed the subsurface investigation on August 7 and 8, 2018 to evaluate underlying soil
conditions. This fieldwork consisted of site reconnaissance, and the excavation of four exploratory
soil borings and two percolation test holes. The borings were advanced to a maximum explored
depth of approximately 20 feet below the ground surface (bgs). Bulk samples were collected from
the cuttings, and relatively undisturbed samples were collected by driving Standard Penetration Test
(SPT) and Modified California (CAL) samplers. The borings on the upper portion of the site were
excavated with a tripod-supported, six-inch-diameter, solid-stem auger. Based on limited
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accessibility, the two borings at the base of the existing slope adjacent to the rip rap were advanced
with a manually operated auger. Approximate locations of the soil borings and test holes are shown
on the attached Figure 2.
Soils were logged in the field by a CTE Engineering Geologist, and were visually classified in
general accordance with the Unified Soil Classification System. The field descriptions have been
modified, where appropriate, to reflect laboratory test results. Boring logs, including descriptions of
the soils encountered, are included in Appendix B. The approximate locations of the borings are
presented on Figure 2.
3.2 Laboratory Testing
Laboratory tests were conducted on selected soil samples for classification purposes, and to evaluate
physical properties and engineering characteristics. Laboratory tests included: In-Place Moisture
and Density, Expansion Index, Grain Size Analysis, Direct Shear, and Chemical Characteristics.
Test descriptions and laboratory test results are included in Appendix C.
4.0 PERCOLATION TESTING
The specific stormwater BMP locations were not known at the time of percolation testing.
Therefore, testing was performed in two representative locations in the central portion of the site
west of the existing structure. The percolation test holes were excavated to depths of approximately
3.1 and 5.3 feet bgs. The attached Figure 2 shows the approximate percolation test locations. The
evaluation was performed in accordance with Appendix C of the Model BMP Design Manual for the
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San Diego Region “Geotechnical and Groundwater Investigation Requirements”, dated January
2018.
4.1 Percolation Test Methods
The percolation tests were performed in general accordance with methods approved by the San
Diego Region BMP Design Manual with a presoak period of approximately 18 to 19 hours.
Percolation test results and calculated infiltration rates are presented below in Table 4.2. Field Data
and percolation to infiltration calculations are included in Appendix F.
4.2 Calculated Infiltrated Rate
As per the San Diego Region BMP design documents (2018) infiltration rates are to be evaluated
using the Porchet Method. San Diego BMP design documents utilized the Porchet Method through
guidance of the County of Riverside (2011). The intent of calculating the infiltration rate is to take
into account bias inherent in percolation test borehole sidewall infiltration that would not occur at a
basin bottom where such sidewalls are not present.
The infiltration rate (It) is derived by the equation:
It = ΔH πr2 60 = ΔH 60 r
Δt(πr2 +2πrHavg) Δt(r+2Havg)
Where:
It = tested infiltration rate, inches/hour
ΔH = change in head over the time interval, inches
Δt = time interval, minutes
* r = effective radius of test hole
Havg = average head over the time interval, inches
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Given the measured percolation rates, the calculated infiltration rates are presented with and without
a Factor of Safety applied in Table 4.2 below. The civil engineer of record should determine an
appropriate factor of safety to be applied via completion of Worksheet D.5-1 of County of San
Diego “Best Management Practice Design Manual”, Appendix D or other approved methods. The I-
8 Worksheet is included in Appendix G of this report. CTE does not recommend using a factor of
safety of less than 2.0.
TABLE 4.2
RESULTS OF PERCOLATION TESTING WITH FACTOR OF SAFETY APPLIED
Test
Location
Test Depth
(inches)
Case Geologic Unit Percolation
Rate (inches
per hour)
Infiltration
Rate (inches
per hour)
Infiltration Rate
with FOS of 2
Applied (inches
per hour)
P-1 63 II Qop 15.00 1.27 0.63
P-2 37 II Qop 20.25 3.71 1.85
NOTES Water level was measured from a fixed point at the top of the hole.
Weather was sunny and warm during percolation testing.
Qop = Quaternary Old Paralic Deposits
The test holes were six inches in diameter.
5.0 GEOLOGY
5.1 General Setting
Carlsbad is located within the Peninsular Ranges physiographic province that is characterized by
northwest-trending mountain ranges, intervening valleys, and predominantly northwest trending
regional faults. The greater San Diego Region can be further subdivided into the coastal plain area,
a central mountain–valley area and the eastern mountain valley area. The project site is located
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within the coastal plain area that is characterized by Cretaceous, Tertiary, and Quaternary
sedimentary deposits that onlap an eroded basement surface consisting of Jurassic and Cretaceous
crystalline rocks.
5.2 Geologic Conditions
Based on the regional geologic map prepared by Kennedy and Tan (2007), the near surface geologic
units that underlie the site consist of Quaternary Marine Beach Deposits, Quaternary Old Paralic
Deposits, Unit 6-7 and the Tertiary Santiago Formation (Figure 3). Based on recent explorations,
Quaternary Slopewash and Residual Soil were observed overlying the Old Paralic Deposits. The
Tertiary Santiago Formation was encountered at depth and the Marine Beach Deposits were
observed within the western portion of the site. Descriptions of the geologic units observed during
the recent investigation are presented below. Surficial geologic materials are depicted on Figure 2,
and a generalized geologic cross-section is presented on Figure 2A.
5.2.1 Quaternary Marine Beach Deposits
Where observed, the Marine Beach Deposits generally consist of loose, light gray, poorly
graded fine grained sand. This unit consists of the active beach deposits located on the
western portion of the site.
5.2.2 Quaternary Slopewash
Where observed, the Slopewash generally consists of loose, reddish brown, silty fine to
medium grained sand. This unit is relatively thin and was observed at the base of the west
facing slope.
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5.2.3 Residual Soil
Where observed, the Residual Soil generally consists of loose to medium dense, dark brown,
silty to clayey fine to medium grained sand. Exploratory excavations encountered Residual
Soil to a maximum depth of approximately 3.0 feet (bgs). This unit is relatively thin and
blankets the underlying Old Paralic Deposits.
5.2.4 Quaternary Old Paralic Deposits
Quaternary Old Paralic Deposits were observed beneath the surficial soils in all of the
borings. Where observed, these materials generally consist of medium dense to dense,
reddish brown, silty to clayey fine to medium grained sandstone. This unit is a generally
massive flat-lying terrace that unconformably overlies the Santiago formation.
5.2.5 Tertiary Santiago Formation
Tertiary Santiago Formation was observed as the underlying geologic unit beneath the site.
Where observed, these materials generally consist of very dense, light gray, fine grained
sandstone. Based on regional mapping by Kennedy and Tan (2007) and observation of cliff
exposures, this unit is generally thinly to thickly bedded, and dips to the north and east with
dip angles ranging from approximately 4 to 10 degrees, which represents neutral to favorable
geologic structure. Significant jointing was not observed in nearby exposures and is not
anticipated at the site. The Tertiary Santiago Formation is anticipated to underlie the entire
site at depth beneath the Old Paralic Deposits and makes up the wave-cut platform at the toe
of the bluff that extends to the west.
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5.3 Groundwater Conditions
During the recent investigation, minor seepage was encountered at an approximate depth of five feet
bgs in B-1 (approximate elevation 8 feet) at the base of the western facing slope. This water is likely
derived from excess irrigation water locally accumulating on top of the relatively impermeable
Santiago Formation. Groundwater or seepage was not observed in the other borings that extended to
a depth of approximately 20 feet bgs (approximate elevation 9 feet) including Boring B-1A that was
advanced adjacent to Boring B-1 at the same approximate surface elevation of 14 feet. The minor
amount of water locally observed during the recent investigation is not anticipated to impact the
global stability of the slope or adversely affect shallow construction activities, provided proper site
drainage is designed, installed, and maintained as per the recommendations of the project civil
engineer of record. However, if the amount of water discharging into the subgrade beneath the site
is dramatically increased soil softening and erosion may occur, potentially resulting in stability
issues. Recommendations to construct the proposed retention basins with impermeable liners are
presented herein to minimize such potential for subgrade saturation and associated effects.
5.4 Geologic Hazards
Geologic hazards considered to have potential impacts to site development were evaluated based on
field observations, literature review, and laboratory test results. The following paragraphs discuss
geologic hazards considered and associated potential risk to the site.
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5.4.1 Surface Fault Rupture
Based on the site reconnaissance and review of referenced literature, the site is not within a
State of California-designated Alquist-Priolo Earthquake Fault Studies Zone and no known
active fault traces underlie or project toward the site. According to the California Division
of Mines and Geology, a fault is active if it displays evidence of activity in the last 11,000
years (Hart and Bryant, 1997). As such, the potential for surface rupture from displacement
or fault movement beneath the proposed improvements is considered to be low.
5.4.2 Local and Regional Faulting
The California Geological Survey (CGS) and the United States Geological Survey (USGS)
broadly group faults as “Class A” or “Class B” (Cao, 2003; Frankel et al., 2002). Class A
faults are identified based upon relatively well-defined paleoseismic activity, and a fault-slip
rate of more than 5 millimeters per year (mm/yr). In contrast, Class B faults have
comparatively less defined paleoseismic activity and are considered to have a fault-slip rate
less than 5 mm/yr. The nearest known Class B fault is the Rose Canyon Fault, which is
approximately 7.0 kilometers from of the site (Blake, T.F., 2000). The nearest known Class
A fault is the Temecula segment of the Elsinore Fault, which is located approximately 40.6
kilometers from of the site. The attached Figure 4 shows regional faults and seismicity with
respect to the site.
The site could be subjected to significant shaking in the event of a major earthquake on any
of the faults noted above or other faults in the southern California or northern Baja California
area.
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5.4.3 Liquefaction and Seismic Settlement Evaluation
Liquefaction occurs when saturated fine-grained sands or silts lose their physical strengths
during earthquake-induced shaking and behave like a liquid. This is due to loss of
point-to-point grain contact and transfer of normal stress to the pore water. Liquefaction
potential varies with water level, soil type, material gradation, relative density, and probable
intensity and duration of ground shaking. Seismic settlement can occur with or without
liquefaction; it results from densification of loose soils.
The site is underlain at shallow depths by medium dense to very dense Old Paralic Deposits
and Tertiary Santiago Formation. Based on the noted subsurface conditions, the potential for
liquefaction or significant seismic settlement in the site improvement areas is considered to
be low.
5.4.4 Tsunamis, Sea Surface Super Elevation and Seiche Evaluation
Based on emergency planning maps prepared by California Emergency Management Agency
and CGS, the site is not located in a zone of potential tsunami inundation. In addition,
oscillatory waves (seiches) are considered unlikely due to the absence of large nearby
confined bodies of water.
According to McCulloch (1985), the potential in the San Diego County coastal area for
“100-year” and “500-year” tsunami waves is approximately five and eight feet, or less. This
suggests that there is a low probability of a tsunami reaching the developed portion of the
site based on elevation of the improvements at greater than 26 feet above mean sea level
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(msl). However, the lower portion of the western slope may be susceptible to erosion
damage if a tsunami were to reach the site.
The lower portion of the slope could also be potentially subject to erosion if a sea surface
super elevation were to occur during a significant large swell storm event and the waves
were able to overtop the rip rap. This has not occurred in the 32 years the rip rap has been in
place, a period that has included numerous large storm events. Based on the investigation
findings, the likelihood of a tsunami or storm event during a sea surface super elevation
impacting the proposed improvement area of the site is considered to be low but the lower
portion the bluff may be susceptible to erosion.
5.4.5 Landsliding and Slope Stability
The developed portion of the site is set back approximately 30 feet from the top of an
approximately 15 feet high 1.4:1 (horizontal: vertical) slope that descends to the southwest.
According to mapping by Tan (1995), the site is located in area 2.0, which is described as
“Marginally Susceptible” to landsliding. Kennedy and Tan (2007) do not indicate the
presence of mapped landslides at the subject site. In addition, on site field observations did
not indicate the presence of deep gross instabilities, and bedding orientations generally
indicate neutral to favorable bedding with respect to the descending slope. Based on the
investigation findings, the potential for deep seated landslides at the subject site is
considered to be low.
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The final input and output from the limited evaluation of slope stability is presented in
Appendix E. For the analysis, the existing slope was modeled based on site topographic and
geologic conditions. Based on laboratory testing, the minimum soil strength values utilized
for the Quaternary Old Paralic Deposits, which is the primary unit making up the existing
slope, were phi = 38o and cohesion = 100 psf. Strength values for the other units were
conservatively estimated based on previous testing and observations made during the
investigation. The analysis, which was performed utilizing SLOPE/W slope stability
software, yielded a factor of safety of 2.1.
Based on the evaluation, the existing slope condition exhibits a global factor of safety in
excess of 1.5. However, residual and slopewash soils in the western portion of the site are
susceptible to potential erosion and may locally develop shallow slumps and failures.
Currently the rip rap placed at the base of the slope and thick ice plant throughout the
existing slope face appear to be providing adequate erosion protection. Based on the
investigation findings, slope instability is not anticipated to impact the proposed
improvement area of the site provided erosion protection measures are maintained and the
minimum City of Carlsbad Costal Shoreline Development Overlay Zone setbacks are
implemented. In addition, the proposed second story residential addition will not modify the
existing structural footprint and is not anticipated to have a negative impact on the overall
stability of the bluff.
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5.4.6 Compressible and Expansive Soils
The near surface Slope Wash and Residual Soil encountered at the site are considered to be
potentially compressible in their current condition. Therefore, if new foundations are
proposed, it is recommended that these soils be overexcavated and properly compacted
beneath proposed improvement areas as recommended herein and as determined to be
necessary during construction. Alternatively, new footings should be extended to bear
entirely in competent native Old Paralic Deposits. Based on field data, site observations, and
CTE’s experience with similar soils in the vicinity of the site, dense native soils underlying
the site are not considered to be subject to significant compressibility under the proposed
loads.
Laboratory testing results indicate that the granular site exhibit a Very Low expansion
potential (Expansion Index of 20 or less). Therefore, expansive soils are generally not
anticipated to present significant adverse impacts to site development. Additional evaluation
of near-surface soils should be performed based on field observations during grading and
excavation activities.
5.4.7 Corrosive Soils
Testing of representative site soils was performed to evaluate the potential corrosive effects
on concrete foundations and buried metallic utilities. Soil environments detrimental to
concrete generally have elevated levels of soluble sulfates and/or pH levels less than 5.5.
According to the American Concrete Institute (ACI) Table 318 4.3.1, specific guidelines
have been provided for concrete where concentrations of soluble sulfate (SO4) in soil exceed
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0.10 percent by weight. These guidelines include low water: cement ratios, increased
compressive strength, and specific cement type requirements. A minimum resistivity value
less than approximately 5,000 ohm-cm and/or soluble chloride levels in excess of 200 ppm
generally indicate a corrosive environment for buried metallic utilities and untreated
conduits.
Chemical test results indicate that near-surface soils at the site generally present a negligible
corrosion potential for Portland cement concrete. Based on resistivity and chloride testing,
the site soils have been interpreted to have a moderate to severe corrosivity potential to
buried metal improvements.
Based on the results of the limited testing performed, it is likely prudent to utilize plastic
piping and conduits where buried and feasible. However, CTE does not practice corrosion
engineering. Therefore, if corrosion of metallic or other improvements is of more significant
concern, a qualified corrosion engineer could be consulted.
6.0 BLUFF EVALUATION
6.1 Review of Historic Topography
A series of topographic maps of the Oceanside and San Luis Rey Quadrangles were collected from
EDR Environmental Data Resources, Inc. The topographic maps reviewed are presented in the table
below.
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TABLE 1
Quadrangle Year Series Scale
Oceanside 1893 15 minute 1:62500
Oceanside 1898 15 minute 1:62500
Oceanside 1901 15 minute 1:62500
Oceanside 1947 15 minute 1:50000
San Luis Rey 1948 7.5 minute 1:24000
San Luis Rey 1949 7.5 minute 1:24000
San Luis Rey 1968 7.5 minute 1:24000
San Luis Rey 1975 7.5 minute 1:24000
San Luis Rey 1997 7.5 minute 1:24000
San Luis Rey 2012 7.5 minute 1:24000
Based on our review, it appears that the surface elevation of the upper portion of the site is indicated
to be greater than 50 feet msl on the 1893, 1898, and 1901 maps. The 1947 to 2012 maps indicate
the upper surface elevation between approximately 35 to 38 feet msl, which is consistent with
current elevations. The difference in site elevation is likely due to the difference in mapping
precision based on the change in reported elevation occurring between 1901 and 1947 before the
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area was developed. It does not appear that the top of the terrace has been significantly eroded or
excavated in that time frame.
The present surface elevations, as shown on Figure 2, range from sea level on the western limit of
the site to approximately 37 feet msl on the eastern portion of the site adjacent to Tierra Del Oro.
Copies of the topographic maps are presented in Appendix H.
6.2 Review of Historic Photography
Aerial and surface photographs of the site and surrounding area were reviewed to help re-construct
the site development history and provide correlative data for the review of the historic topographic
maps. Aerial photographs were collected from the California Coastal Records Project
(www.californiacoastline.org), (Appendix I), and a data search completed by EDR Environmental
Data Resources Inc., (Appendix J).
6.2.1 Aerial Photographs
Oblique aerial photographs of the Carlsbad area available from the California Coastal Project
included photographs from 1979, 1989, 2008 and 2013. Aerial photographs from the EDR
data search included photographs from 1928, 1939, 1946, 1953, 1964, 1967, 1970, 1979,
1985, 1990, 1994, 2005, 2009, 2012, and 2016.
Review of the aerial photographs shows that Tierra Del Oro was constructed and
development of the area began between the years of 1953 and 1964. The subject site was
developed between 1970 and 1979. Based on review of a previous adjacent investigation
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(GEI 2013) in addition to the aerial photographs, a limited amount of smaller class boulder
rip rap was placed south of the site in the 1970’s in an attempt to stabilize the lower portion
of the bluff. Two significant storm events that occurred in 1978 and 1983 resulted in severe
erosion damage to a nearby recreational area. In response to damage caused by the storms,
the recreation area was closed and the current larger class rip rap (8- to 12- ton class) was
placed at the toe of the existing western slope from 1985 to 1986. This placement of rip-rap
extends the entire length of Tierra Del Oro providing bluff erosion protection for the site and
adjacent areas. Following placement of the larger class rip rap, the coastline along this
portion of bluff has remained relatively unchanged.
Due to the construction of jetties, rip rap barriers and other erosion resistant structures
throughout the region, supply of sand to beaches has been reduced by approximately 26%
according to the California Beach Restoration Study performed by Griggs in 2002. This
beach reduction can be observed on the aerial photographs between 1967 and 1979 following
construction of jetty structures associated with the power plant located north of the site.
6.3 Bluff Profiles
A cross section was constructed perpendicular to the bluff, which shows the current surface and
geologic units encountered during the field investigation (Figure 2A). The location of the section is
shown on the site Geologic/ Exploration Location Map (Figure 2). The coastal bluff edge, as
determined by the Coastal Bluffs and Beaches Guidelines, is currently at an approximate elevation
of 27 feet msl. The toe of bluff was interpreted based on information from the westernmost borings
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at the toe of slope and estimated location of the present day abrasion platform based on our aerial
photograph and literature reviews as well as reef exposures observed during the field investigation.
The depth of beach deposits and thickness of rip rap over the Santiago Formation (from which the
wave-cut platform is derived) were based on borings at the toe of slope and reef exposures.
6.4 Seacliff Recession
The coastline in San Diego County has been divided into several different segments that have been
evaluated for seacliff recession with rates based on bedrock type, rock strength, structural
weaknesses, wave energy, and terrestrial processes. As part of our site specific evaluation of seacliff
recession we reviewed two studies performed by Moore, Benumof and Griggs (1999) and Benumof
and Griggs (1999). These studies determined rates of seacliff recession by utilizing a high-
resolution state-of-the-art, soft-copy photogrammetric and geographic information system (GIS)
imaging laboratory to compare aerial photographs collected by the National Oceanic and
Atmospheric Administration (NOAA) in 1994 to historic aerial photographs that were flown in
1932, 1949, 1952 and 1956.
The study performed by Moore, Benumof and Griggs (1999) titled “Erosion Hazards in Santa Cruz
and San Diego Counties, California” determined the Carlsbad area to have a seacliff recession rate
ranging from 3 to 58 cm/year between 1956 and 1994.
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The study performed by Benumof and Griggs (1999) titled “The Dependence of Seacliff Erosion
Rates on Cliff Material Properties and Physical Processes: San Diego County, California”
determined that the Carlsbad area had a recession rate of 43.02 cm per year.
These rates are largely based on geologic composition of the seacliff, significant storm events, and
man-made protection. The wide range in the erosion rates presented above can be explained by the
presence and height of the erosion resistant Santiago Formation material and the presence of man-
made protection “armor” being factored into the duration of time the seacliff was exposed to erosion.
Relatively erodible Old Paralic Deposits (terrace materials) at an elevation that is exposed to the
ocean swell, will typically erode much faster than an area where the erosion resistant Santiago
Formation is present and extends to a higher elevation. The difference in rates can also be impacted
by armoring portions of the erodible material, which would result in unprotected portions of the
seacliff eroding much faster than the armored segments. This difference in erosion rate was also
exaggerated by localized armoring occurring before a number of significant storm events that
occurred between 1978 and 1994, which was a period of accelerated erosion.
Based on review of bluff recession studies and observations of the historic aerial photographs, areas
that have been adequately armored were able to stop or significantly reduce recession of the seacliff.
At the subject site, the rip rap that exists at the toe of the western slope has provided adequate
protection of the bluff since 1986 and, based on recent observation, shows minimal signs of
deterioration and has maintained a configuration that remains interlocked and secure. This rip rap
has been in place during the significant coastal storms of 1988, 1992-1994 and 1997-1998 that
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produced ocean swells up to 20 feet in height and has not been noticeably compromised. In
addition, the entire slope that extends up from the rip rap has been planted with thick vegetation that
should minimize erosion resulting from precipitation and aeolian processes.
Based on the investigation findings, it is CTE’s opinion that the seacliff adjacent to the site is
adequately armored and protected from significant erosion. Provided the City of Carlsbad Costal
Shoreline Development Overlay Zone setbacks are recognized and the rip rap and existing slope are
maintained, the proposed second story addition is considered to be adequately protected from
seacliff recession for the anticipated life of the structure.
7.0 CONCLUSIONS AND RECOMMENDATIONS
7.1 General
CTE concludes that the proposed improvements on the site are feasible from a geotechnical
standpoint, provided the preliminary recommendations in this report are incorporated into the design
and construction of the project. Recommendations for the proposed earthwork and improvements
are included in the following sections and Appendix D. However, recommendations in the text of
this report supersede those presented in Appendix D should conflicts exist. These preliminary
recommendations should either be confirmed as appropriate or updated following removal of
existing improvements and observations during site preparation.
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7.2 Site Preparation
If new foundations or slabs are proposed, areas to receive new footings and/or flatwork should be
cleared of any existing construction debris and vegetation not suitable for structural backfill and be
properly disposed of offsite.
It is anticipated that new structure footings will be extended to the depth of competent native
materials. Beneath other proposed improvements, such as slabs on grade, pavement, and hardscape
areas, existing soils should be excavated to the depth of two feet below proposed grades, or to the
depth of competent underlying materials, whichever is greater.
If encountered, existing below-ground utilities should be redirected around proposed structures.
Existing utilities at an elevation to extend through the proposed footings should generally be sleeved
and caulked to minimize the potential for moisture migration below the building slabs. Abandoned
pipes exposed by grading should be securely capped or filled with minimum two-sack cement/sand
slurry to help prevent moisture from migrating beneath foundation and slab soils.
Overexcavations adjacent to existing structures should generally not extend below a 1:1 plane
extended down from the bottom of the existing footings or as recommended during grading based on
the exposed conditions. Depending on the depth and proximity of the existing building footings to
remain, alternating slot excavations could be required during earthwork.
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A CTE representative should observe the exposed ground surface prior to placement of compacted
fill to document and verify the competency of the encountered subgrade materials. If unsuitable
material is exposed at the base of excavations additional removals may be recommended. After
approval by this office, the exposed subgrades to receive fill should be scarified a minimum of nine
inches, moisture conditioned, and properly compacted prior to additional compacted fill placement.
7.3 Site Excavation
Based on CTE’s observations, shallow excavations at the site should be feasible using well-
maintained heavy-duty construction equipment run by experienced operators. However, excavations
within the Old Paralic Deposits could encounter zones that are sensitive to caving and/or erosion,
and may not effectively remain standing vertical or near-vertical, even at shallow or minor heights
and for short periods of time.
7.4 Fill Placement and Compaction
Following the recommended overexcavation of loose or disturbed soils, areas to receive fills should
be scarified approximately nine inches, moisture conditioned, and properly compacted. Fill and
backfill should be compacted to a minimum relative compaction of 90 percent at a moisture content
of at least two percent above optimum, as evaluated by ASTM D 1557. The optimum lift thickness
for fill soil depends on the type of compaction equipment used. Generally, backfill should be placed
in uniform, horizontal lifts not exceeding eight inches in loose thickness. Fill placement and
compaction should be conducted in conformance with local ordinances, and should be observed and
tested by a CTE geotechnical representative.
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7.5 Fill Materials
Properly moisture-conditioned very low to low expansion potential soils derived from the on-site
excavations are considered suitable for reuse on the site as compacted fill. If used, these materials
should be screened of organics and materials generally greater than three inches in maximum
dimension. Irreducible materials greater than three inches in maximum dimension should generally
not be used in shallow fills (within three feet of proposed grades). In utility trenches, adequate
bedding should surround pipes.
Imported fill beneath structures, flatwork, and pavements should have an Expansion Index of 20 or
less (ASTM D 4829). Proposed import fill soils for use in structural or slope areas should be
evaluated by the geotechnical engineer before being transported to the site.
If retaining walls are proposed, backfill located within a 45-degree wedge extending up from the
heel of the wall should consist of soil having an Expansion Index of 20 or less (ASTM D 4829) with
less than 30 percent passing the No. 200 sieve. The upper 12 to 18 inches of wall backfill should
consist of lower permeability soils, in order to reduce surface water infiltration behind walls. The
project structural engineer and/or architect should detail proper wall backdrains, including gravel
drain zones, fills, filter fabric, and perforated drain pipes. However, a conceptual wall backdrain
detail, which may be suitable for use at the site, is provided as Figure 5.
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7.6 Temporary Construction Slopes
The following recommended slopes should be relatively stable against deep-seated failure, but may
experience localized sloughing. On-site soils are considered Type B and Type C soils with
recommended slope ratios as set forth in Table 7.6.
TABLE 7.6
RECOMMENDED TEMPORARY SLOPE RATIOS
SOIL TYPE SLOPE RATIO
(Horizontal: vertical) MAXIMUM HEIGHT
B (Old Paralic Deposits) 1:1 (OR FLATTER) 10 Feet
C (Undocumented Fill and
Residual Soil) 1.5:1 (OR FLATTER) 10 Feet
Actual field conditions and soil type designations must be verified by a "competent person" while
excavations exist, according to Cal-OSHA regulations. In addition, the above sloping
recommendations do not allow for surcharge loading at the top of slopes by vehicular traffic,
equipment or materials. Appropriate surcharge setbacks must be maintained from the top of all
unshored slopes.
7.7 Foundations and Slab Recommendations
The following recommendations are for preliminary design purposes only. These foundation
recommendations should be re-evaluated after review of the project grading and foundation plans,
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and after completion of rough grading of the building pad areas. Upon completion of rough pad
grading, Expansion Index of near surface soils should be verified, and these recommendations
should be updated, if necessary.
7.7.1 Foundations
Foundation recommendations presented herein are based on the anticipated very low
expansion potential of site soils (Expansion Index of 20 or less).
Following the recommended shallow preparatory grading (as necessary), continuous and
isolated spread footings are anticipated to be suitable for use at this site. Foundation
dimensions and reinforcement should be based on allowable bearing values of 2,500 pounds
per square foot (psf) for minimum 15-inch wide footings embedded a minimum of 24-inches
below lowest adjacent subgrade elevation. Isolated footings should be at least 24 inches in
minimum dimension. The allowable bearing value may be increased by one-third for short-
duration loading, which includes the effects of wind or seismic forces. Based on the
recommendations provided, it is anticipated that all footings will be extended to bear in
competent native materials. Footings should not span cut to fill interfaces.
Minimum reinforcement for continuous footings should consist of four No. 5 reinforcing
bars; two placed near the top and two placed near the bottom, or as per the project structural
engineer. The structural engineer should design isolated footing reinforcement. An
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uncorrected subgrade modulus of 140 pounds per cubic inch is considered suitable for elastic
foundation design.
The structural engineer should provide recommendations for reinforcement of any spread
footings and footings with pipe penetrations. Footing excavations should generally be
maintained above optimum moisture content until concrete placement.
7.7.2 Foundation Settlement
The maximum total static settlement is expected to be on the order of one inch and the
maximum differential settlement is expected to be on the order of 0.5 inch. Due to the
generally dense nature of underlying materials, dynamic settlement is not expected to
adversely affect the proposed buildings.
7.7.3 Foundation Setback
Footings for structures should be designed such that the horizontal distance from the face of
adjacent slopes to the outer edge of the footing is at least 12 feet. In addition, footings
should bear beneath a 1:1 plane extended up from the nearest bottom edge of adjacent
trenches and/or excavations. Deepening of affected footings may be a suitable means of
attaining the prescribed setbacks.
7.7.4 Interior Concrete Slabs
Lightly loaded concrete slabs should be a minimum of 5.0 inches thick. Minimum slab
reinforcement should consist of #4 reinforcing bars placed on maximum 18-inch centers,
each way, at or above mid-slab height, but with proper cover. More stringent
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recommendations per the project structural engineer could be provided.
In moisture-sensitive floor areas, a suitable vapor retarder of at least 15-mil thickness (with
all laps or penetrations sealed or taped) overlying a four-inch layer of consolidated aggregate
base or gravel (with SE of 30 or more) should be installed. An optional maximum two-inch
layer of similar material may be placed above the vapor retarder to help protect the
membrane during steel and concrete placement. This recommended protection is generally
considered typical in the industry. If proposed floor areas or coverings are considered
especially sensitive to moisture emissions, additional recommendations from a specialty
consultant could be obtained. CTE is not an expert at preventing moisture penetration
through slabs. A qualified architect or other experienced professional should be contacted if
moisture penetration is a more significant concern.
Slabs subjected to heavier loads may require thicker slab sections and/or increased
reinforcement. A 110-pci subgrade modulus is considered suitable for elastic design of
minimally embedded improvements such as slabs-on-grade.
Subgrade materials should be maintained or brought to a minimum of two percent or greater
above optimum moisture content until slab underlayment and concrete are placed.
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7.8 Seismic Design Criteria
The seismic ground motion values listed in the table below were derived in accordance with the
ASCE 7-10 Standard and 2016 CBC. This was accomplished by establishing the Site Class based on
the soil properties at the site, and calculating the site coefficients and parameters using the United
States Geological Survey Seismic Design Maps application and site coordinates of 33.13228° north
latitude and -117.33654° longitude. These values are intended for the design of structures to resist
the effects of earthquake ground motions.
TABLE 7.8
SEISMIC GROUND MOTION VALUES
PARAMETER VALUE CBC REFERENCE (2016)
Site Class C ASCE 7, Chapter 20
Mapped Spectral Response
Acceleration Parameter, SS 1.176 Figure 1613.3.1 (1)
Mapped Spectral Response
Acceleration Parameter, S1
0.452 Figure 1613.3.1 (2)
Seismic Coefficient, Fa 1.000 Table 1613.3.3 (1)
Seismic Coefficient, Fv 1.348 Table 1613.3.3 (2)
MCE Spectral Response
Acceleration Parameter, SMS 1.176 Section 1613.3.3
MCE Spectral Response
Acceleration Parameter, SM1 0.609 Section 1613.3.3
Design Spectral Response
Acceleration, Parameter SDS 0.784 Section 1613.3.4
Design Spectral Response
Acceleration, Parameter SD1 0.406 Section 1613.3.4
PGAM 0.474 ASCE 7, Equation 11.8-1
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7.9 Lateral Resistance and Earth Pressures
Lateral loads acting against structures may be resisted by friction between the footings and the
supporting soil or passive pressure acting against structures. If frictional resistance is used,
allowable coefficients of friction of 0.30 (total frictional resistance equals the coefficient of friction
multiplied by the dead load) for concrete cast directly against compacted fill is recommended. A
design passive resistance value of 250 pounds per square foot per foot of depth (with a maximum
value of 1,500 pounds per square foot) may be used. The allowable lateral resistance can be taken as
the sum of the frictional resistance and the passive resistance, provided the passive resistance does
not exceed two-thirds of the total allowable resistance.
If proposed, retaining walls backfilled using granular soils may be designed using the equivalent
fluid unit weights given in Table 7.9 below.
Lateral pressures on cantilever retaining walls (yielding walls) over six feet high due to
earthquake motions may be calculated based on work by Seed and Whitman (1970). The total
TABLE 7.9
EQUIVALENT FLUID UNIT WEIGHTS (Gh)
(pounds per cubic foot)
WALL TYPE LEVEL BACKFILL
SLOPE BACKFILL
2:1 (HORIZONTAL:
VERTICAL)
CANTILEVER WALL
(YIELDING) 35 55
RESTRAINED WALL 55 65
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lateral earth pressure against a properly drained and backfilled cantilever retaining wall above
the groundwater level can be expressed as:
PAE = PA + ΔPAE
For non-yielding (or “restrained”) walls, the total lateral earth pressure may be similarly
calculated based on work by Wood (1973):
PKE = PK + ΔPKE
Where PA/b = Static Active Earth Pressure = GhH2/2
PK/b = Static Restrained Wall Earth Pressure = GhH2/2
ΔPAE/b = Dynamic Active Earth Pressure Increment = (3/8) kh γH2/2
ΔPKE/b = Dynamic Restrained Earth Pressure Increment = kh γH2/2
b = unit length of wall (usually 1 foot)
kh = 2/3 PGAm (PGAm given previously Table 5.8)
Gh = Equivalent Fluid Unit Weight (given previously Table 5.9)
H = Total Height of the retained soil
γ = Total Unit Weight of Soil ≈ 135 pounds per cubic foot
The static and increment of dynamic earth pressure in both cases may be applied with a line of
action located at H/3 above the bottom of the wall (SEAOC, 2013).
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These values assume non-expansive backfill and free-draining conditions. Measures should be taken
to prevent moisture buildup behind all retaining walls. Drainage measures should include free-
draining backfill materials and sloped, perforated drains. These drains should discharge to an
appropriate off-site location. Figure 5 shows a conceptual wall backdrain detail that may be suitable
for walls at the subject site. Any waterproofing should be as specified by the project architect.
7.10 Exterior Flatwork
Flatwork should be installed with crack-control joints at appropriate spacing as designed by the
project architect to reduce the potential for cracking in exterior flatwork caused by minor movement
of subgrade soils and concrete shrinkage. Additionally, it is recommended that flatwork be installed
with at least number 4 reinforcing bars at 18-inch centers, each way, at or above mid-height of slab,
but with proper concrete cover, or with other reinforcement per the applicable project designer.
Flatwork that should be installed with crack control joints, includes driveways, sidewalks, and
architectural features. All subgrades should be prepared according to the earthwork
recommendations previously given before placing concrete. Positive drainage should be established
and maintained next to all flatwork. Subgrade materials should be maintained at a minimum of two
percent above optimum moisture content before concrete placement.
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7.11 Vehicular Pavement
If new pavements are proposed, Table 7.11 presents preliminary pavement sections utilizing
estimated Resistance “R” Value and traffic index. Beneath pavement areas, the upper 12 inches of
subgrade and all base materials should be compacted to 95% relative compaction in accordance with
ASTM D1557, and at a minimum of two percent above optimum moisture content.
TABLE 7.11
RECOMMENDED PAVEMENT THICKNESS
Traffic Area
Assumed
Traffic Index
Preliminary
Subgrade
“R”-Value
Asphalt Pavements
Portland Cement
Concrete
Pavements, on
Subgrade Soils
(inches)
AC
Thickness
(inches)
Class II
Aggregate Base
Thickness
(inches)
Automobile
Parking Areas 5.0 30+ 3.0 8.0 6.5
* Caltrans class 2 aggregate base
** Concrete should have a modulus of rupture of at least 600 psi
Following rough site grading, CTE recommends laboratory testing of at-grade soils for as-graded
“R”-Value.
Asphalt paved areas should be designed, constructed, and maintained in accordance with the
recommendations of the Asphalt Institute, or other widely recognized authority. Concrete paved
areas should be designed and constructed in accordance with the recommendations of the American
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Concrete Institute or other widely recognized authority, particularly with regard to thickened edges,
joints, and drainage. The Standard Specifications for Public Works construction (“Greenbook”) or
Caltrans Standard Specifications may be referenced for pavement materials specifications.
7.12 Drainage
Surface runoff should be collected and directed away from improvements and slope areas by means
of appropriate erosion-reducing devices and positive drainage should be established around the
proposed improvements. Positive drainage should be directed away from improvements at a
gradient of at least two percent for a distance of at least five feet. However, the project civil
engineers should evaluate the on-site drainage and make necessary provisions to keep surface water
from affecting the site.
Generally, CTE recommends against allowing water to infiltrate building pads or adjacent to slopes.
CTE understands that some agencies are encouraging the use of storm-water cleansing devices. Use
of such devices tends to increase the possibility of adverse effects associated with high groundwater
including slope instability and liquefaction.
7.13 Slopes
The proposed improvement portion of the site is generally flat and no significant slopes were
observed other than the bluff, located approximately 30 feet west of the existing structure. Based on
anticipated soil strength characteristics, fill slopes if proposed, should be constructed at slope ratios
of 2:1 (horizontal: vertical) or flatter. These fill slope inclinations should exhibit factors of safety
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greater than 1.5.
Although properly constructed slopes on this site should be grossly stable, the soils will be
somewhat erodible. Therefore, runoff water should not be permitted to drain over the edges of
slopes unless that water is confined to properly designed and constructed drainage facilities.
Erosion-resistant vegetation should be maintained on the face of all slopes.
Typically, soils along the top portion of a fill slope face will creep laterally. CTE recommends
against building distress-sensitive hardscape improvements within five feet of slope crests, and
against using thickened edges in this area.
7.14 Controlled Low Strength Materials (CLSM)
Controlled Low Strength Materials (CLSM) may be used in lieu of compacted soils below
foundations, within building pads, and/or adjacent to retaining walls or other structures, provided the
appropriate following recommendations are also incorporated. Minimum overexcavation depths
recommended herein beneath bottom of footings, slabs, flatwork, and other areas may be applicable
beneath CLSM if/where CLSM is to be used, and excavation bottoms should be observed by CTE
prior to placement of CLSM. Prior to CLSM placement, the excavation should be free of debris,
loose soil materials, and water. Once specific areas to utilize CLSM have been determined, CTE
should review the locations to determine if additional recommendations are appropriate.
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CLSM should consist of a minimum three-sack cement/sand slurry with a minimum 28-day
compressive strength of 100 psi (or equal to or greater than the maximum allowable short term soil
bearing pressure provided herein, whichever is higher) as determined by ASTM D4832. If re-
excavation is anticipated, the compressive strength of CLSM should generally be limited to a
maximum of 150 psi per ACI 229R-99. Where re-excavation is required, two-sack cement/sand
slurry may be used to help limit the compressive strength. The allowable soils bearing pressure and
coefficient of friction provided herein should still govern foundation design. CLSM may not be used
in lieu of structural concrete where required by the structural engineer.
7.15 Plan Review
CTE should be authorized to review the project grading and foundation plans prior to
commencement of earthwork in order to provide additional recommendations, if necessary.
7.16 Construction Observation
The recommendations provided in this report are based on preliminary design information for the
proposed construction and the subsurface conditions observed in the soil borings. The interpolated
subsurface conditions should be checked by CTE during construction with respect to anticipated
conditions. Upon completion of precise grading, if necessary, soil samples will be collected to
evaluate as-built Expansion Index. Foundation recommendations may be revised upon completion
of grading, and as-built laboratory test results. Additionally, soil samples should be taken in
pavement subgrade areas upon rough grading to refine pavement recommendations as necessary.
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Recommendations provided in this report are based on the understanding and assumption that CTE
will provide the observation and testing services for the project. All earthwork should be observed
and tested in accordance with recommendations contained within this report. CTE should evaluate
footing excavations before reinforcing steel placement.
8.0 LIMITATIONS OF INVESTIGATION
The field evaluation, laboratory testing and geotechnical analysis presented in this report have been
conducted according to current engineering practice and the standard of care exercised by reputable
geotechnical consultants performing similar tasks in this area. No other warranty, expressed or
implied, is made regarding the conclusions, recommendations and opinions expressed in this report.
Variations may exist and conditions not observed or described in this report may be encountered
during construction. This report is prepared for the project as described. It is not prepared for any
other property or party.
The existing structure was built in the 1970s, and the scope of this report did not include
investigation of the as-built foundation conditions or characteristics of said structure, including
determination of footing dimensions. The recommendations provided herein have been developed in
order to reduce the post-construction movement of site improvements. However, even with the
design and construction recommendations presented herein, some post-construction movement and
associated distress may occur.
Geotechnical Investigation
Proposed Buccola Residence Addition
5031 Tierra Del Oro, Carlsbad, California
September 12, 2018 CTE Job No. 10-14444G
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Page 37
The findings of this report are valid as of the present date. However, changes in the conditions of a
property can occur with the passage of time, whether they are due to natural processes or the works
of man on this or adjacent properties. In addition, changes in applicable or appropriate standards
may occur, whether they result from legislation or the broadening of knowledge. Accordingly, the
findings of this report may be invalidated wholly or partially by changes outside CTE’s involvement.
Therefore, this report is subject to review and should not be relied upon after a period of three years.
CTE’s conclusions and recommendations are based on an analysis of the observed conditions. If
conditions different from those described in this report are encountered, CTE should be notified and
additional recommendations, if required, will be provided subject to CTE remaining as authorized
geotechnical consultant of record. This report is for use of the project as described. It should not be
utilized for any other project.
Geotechnical Investigation
Proposed Buccola Residence Addition
5031 Tierra Del Oro, Carlsbad, California
September 12, 2018 CTE Job No. 10-14444G
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Page 38
CTE appreciates this opportunity to be of service on this project. If you have any questions
regarding this report, please do not hesitate to contact the undersigned.
Respectfully submitted,
CONSTRUCTION TESTING & ENGINEERING, INC.
Dan T. Math, GE #2665 Jay F. Lynch, CEG #1890
Principal Engineer Principal Engineering Geologist
Aaron J. Beeby, CEG #2603 Colm J. Kenny, RCE #84406
Project Geologist Project Engineer
SITE
P-1B-1P-2B-2B-3B-2B-1B-1AAA'QopQswQmbTsaB-3Approximate Boring Location (Current Investigation)LEGENDQuaternary Slope WashQswApproximate Geologic ContactB-2Approximate Boring Location (CTE 2004)P-2Approximate Percolation Test LocationQuaternary Old Paralic Deposits overQopTsaTertiary Santiago FormationApproximate Geologic Cross SectionAA'Quaternary Marine Beach DepositsQmb
20ELEVATION (FEET)100DISTANCE (FEET)CROSS SECTION A-A'0500-10-20101502003040-30200-10-20103040-30AA'Proj.~5' NTD=5.7'TD=20.0'TD=19.9'B-1Proj.~15' SB-3B-2QopTsaResidual SoilRip RapQmbExisting ProfileLEGENDQuaternary Marine Beach DepositsQmbApproximate Geologic ContactQuaternary Old Paralic DepositsQopTertiary Santiago FormationTsa
APPROXIMATE
SITE LOCATION
Tsa
Qmb
NOTE: Base Map by Kennedy and Tan, 2007, Geologic Map of the
Oceanside 30' x 60' Quadrangle, California.
LEGEND
Young Alluvial Flood Plain DepositsQya
Qmb Marine Beach Deposits
Old Alluvial Flood Plain DepositsQoa
Very Old Paralic DepositsQvop
Santiago FormationTsa
Qop Old Paralic Deposits
Metasedimentary and MetavolcanicMzuRocks
APPROXIMATESITE LOCATIONLEGENDHISTORIC FAULT DISPLACEMENT (LAST 200 YEARS)HOLOCENE FAULT DISPLACEMENT (DURING PAST 11,700 YEARS)LATE QUATERNARY FAULT DISPLACMENT (DURING PAST 700,000 YEARS) QUATERNARY FAULT DISPLACEMENT (AGE UNDIFFERENTIATED)PREQUATERNARY FAULT DISPLACEMENT (OLDER THAN 1.6 MILLION YEARS)>7.06.5-6.95.5-5.95.0-5.4PERIOD1800- 1869- 1932-1868 1931 2010LAST TWO DIGITS OF M > 6.5EARTHQUAKE YEARMAGNITUDE
1
1
SELECT GRANULAR WALL
BACKFILL COMPACTED
TO 90% RELATIVE COMPACTION
3/4" GRAVEL SURROUNDED
BY FILTER FABRIC (MIRAFI
140 N. OR EQUIVALENT)
-OR-
PREFABRICATED
DRAINAGE BOARD
FINISH GRADE
SPECIFIED BY ARCHITECT
RETAINING WALL
WATERPROOFING TO BE
12" TO 18" OF LOWER PERMEABILITY MATERIAL
COMPACTED TO 90% RELATIVE COMPACTION
1' MIN
4" DIA. PERFORATED PVC
PIPE (SCHEDULE 40 OR
EQUIVALENT). MINIMUM
1% GRADIENT TO SUITABLE
OUTLET
WALL FOOTING
*CONCEPTUAL DRAWING
APPENDIX A
REFERENCES
REFERENCES
1. American Society for Civil Engineers, 2005, “Minimum Design Loads for Buildings and
Other Structures,” ASCE/SEI 7-05.
2. ASTM, 2002, “Test Method for Laboratory Compaction Characteristics of Soil Using
Modified Effort,” Volume 04.08.
3. Benumof, Benjamin T., and Griggs, Gary B., 1999, The Dependence of Seacliff Erosion
Rates on Cliff Material Properties and Physical Processes: San Diego County, California.
4. Benumof, Benjamin T., Storlazzi, Curt D., Seymour, Richard J., and Griggs, Gary B., 2000,
The Relationship Between Incident Wave Energy and Seacliff Erosion Rates: San Diego
County, California.
5. Blake, T.F., 2000, “EQFAULT,” Version 3.00b, Thomas F. Blake Computer Services and
Software.
6. California Building Code, 2016, “California Code of Regulations, Title 24, Part 2, Volume 2
of 2,” California Building Standards Commission, published by ICBO, June.
7. California Division of Mines and Geology, CD 2000-003 “Digital Images of Official Maps
of Alquist-Priolo Earthquake Fault Zones of California, Southern Region,” compiled by
Martin and Ross.
8. California Emergency Management Agency/California Geological Survey, “Tsunami
Inundation Maps for Emergency Planning."
9. Construction Testing and Engineering, 2004, Preliminary Geotechnical Investigation,
Proposed Improvements to McGuire Residence, 5035 Tierra Del Oro Street, Carlsbad,
California, Job No. 10-6766, dated March 2.
10. Geotechnical Exploration, Inc., 2013, Report of Geotechnical Investigation and Costal Bluff
Edge Evaluation, Tierra Del Oro, Carlsbad, California, Job No. 13-10316, dated November
12.
11. Hart, Earl W., Revised 1994, Revised 2007, “Fault-Rupture Hazard Zones in California,
Alquist Priolo, Special Studies Zones Act of 1972,” California Division of Mines and
Geology, Special Publication 42.
12. Jennings, Charles W., 1994, “Fault Activity Map of California and Adjacent Areas” with
Locations and Ages of Recent Volcanic Eruptions.
13. Kennedy, M.P. and Tan, S.S., 2007, “Geologic Map of the Oceanside 30’ x 60’ Quadrangle,
California”, California Geological Survey, Map No. 2.
14. Moore, Laura J., Benumof, Benjamin T., and Griggs, Gary B., 1999, Costal Erosion Hazards
in Santa Cruz and San Diego Counties, California.
15. Reichle, M., Bodin, P., and Brune, J., 1985, The June 1985 San Diego Bay Earthquake
swarm [abs.]: EOS, v. 66, no. 46, p.952.
16. Seed, H.B., and R.V. Whitman, 1970, “Design of Earth Retaining Structures for Dynamic
Loads,” in Proceedings, ASCE Specialty Conference on Lateral Stresses in the Ground and
Design of Earth-Retaining Structures, pp. 103-147, Ithaca, New York: Cornell University.
17. Tan, S. S., and Giffen, D. G., 1995, “Landslide Hazards in the Northern Part of the San
Diego Metropolitan Area, San Diego County, California: Oceanside and San Luis Rey
Quadrangles, Landslide Hazard Identification Map No. 35”, California Department of
Conservation, Division of Mines and Geology, Open-File Report 95-04, State of California,
Division of Mines and Geology, Sacramento, California.
18. Wood, J.H. 1973, Earthquake-Induced Soil Pressures on Structures, Report EERL 73-05.
Pasadena: California Institute of Technology.
APPENDIX B
EXPLORATION LOGS
DEFINITION OF TERMS
PRIMARY DIVISIONS SYMBOLS SECONDARY DIVISIONS
WELL GRADED GRAVELS, GRAVEL-SAND MIXTURES
LITTLE OR NO FINES
POORLY GRADED GRAVELS OR GRAVEL SAND MIXTURES,
LITTLE OF NO FINES
SILTY GRAVELS, GRAVEL-SAND-SILT MIXTURES,
NON-PLASTIC FINES
CLAYEY GRAVELS, GRAVEL-SAND-CLAY MIXTURES,
PLASTIC FINES
WELL GRADED SANDS, GRAVELLY SANDS, LITTLE OR NO
FINES
POORLY GRADED SANDS, GRAVELLY SANDS, LITTLE OR
NO FINES
SILTY SANDS, SAND-SILT MIXTURES, NON-PLASTIC FINES
CLAYEY SANDS, SAND-CLAY MIXTURES, PLASTIC FINES
INORGANIC SILTS, VERY FINE SANDS, ROCK FLOUR, SILTY
OR CLAYEY FINE SANDS, SLIGHTLY PLASTIC CLAYEY SILTS
INORGANIC CLAYS OF LOW TO MEDIUM PLASTICITY,
GRAVELLY, SANDY, SILTS OR LEAN CLAYS
ORGANIC SILTS AND ORGANIC CLAYS OF LOW PLASTICITY
INORGANIC SILTS, MICACEOUS OR DIATOMACEOUS FINE
SANDY OR SILTY SOILS, ELASTIC SILTS
INORGANIC CLAYS OF HIGH PLASTICITY, FAT CLAYS
ORGANIC CLAYS OF MEDIUM TO HIGH PLASTICITY,
ORGANIC SILTY CLAYS
PEAT AND OTHER HIGHLY ORGANIC SOILS
GRAIN SIZES
GRAVEL SAND
COARSE FINE COARSE MEDIUM FINE
12" 3" 3/4" 4 10 40 200
CLEAR SQUARE SIEVE OPENING U.S. STANDARD SIEVE SIZE
ADDITIONAL TESTS
(OTHER THAN TEST PIT AND BORING LOG COLUMN HEADINGS)
MAX- Maximum Dry Density PM- Permeability PP- Pocket Penetrometer
GS- Grain Size Distribution SG- Specific Gravity WA- Wash Analysis
SE- Sand Equivalent HA- Hydrometer Analysis DS- Direct Shear
EI- Expansion Index AL- Atterberg Limits UC- Unconfined Compression
CHM- Sulfate and Chloride RV- R-Value MD- Moisture/Density
Content , pH, Resistivity CN- Consolidation M- Moisture
COR - Corrosivity CP- Collapse Potential SC- Swell Compression
SD- Sample Disturbed HC- Hydrocollapse OI- Organic Impurities
REM- Remolded
FIGURE: BL1
GW
SILTS AND CLAYS
LIQUID LIMIT ISLESS THAN 50
SILTS AND CLAYS
LIQUID LIMIT IS
GREATER THAN 50
SANDS
MORE THAN
HALF OF
COARSE
FRACTION IS
SMALLER THAN
NO. 4 SIEVE
GRAVELS
MORE THAN
HALF OF
COARSE
FRACTION IS
LARGER THAN
NO. 4 SIEVE
CLEAN
GRAVELS
< 5% FINES
GRAVELS WITH FINES
CLEAN
SANDS
< 5% FINES
SANDSWITH FINESCOARSE GRAINED SOILSMORE THAN HALF OF MATERIAL IS LARGER THAN NO. 200 SIEVE SIZEGP
GM
GC
SW
SP
SM
SC
ML
CL
OL
MH
CH
OH
PTFINE GRAINED SOILSMORE THAN HALF OF MATERIAL IS SMALLER THAN NO. 200 SIEVE SIZEHIGHLY ORGANIC SOILS
SILTS AND CLAYSCOBBLESCOBBLESBOULDERS
PROJECT:DRILLER:SHEET:of
CTE JOB NO:DRILL METHOD:DRILLING DATE:
LOGGED BY:SAMPLE METHOD:ELEVATION:Depth (Feet)Bulk SampleDriven TypeBlows/FootDry Density (pcf)Moisture (%)U.S.C.S. SymbolGraphic LogBORING LEGEND Laboratory Tests
DESCRIPTION
Block or Chunk Sample
Bulk Sample
Standard Penetration Test
Modified Split-Barrel Drive Sampler (Cal Sampler)
Thin Walled Army Corp. of Engineers Sample
Groundwater Table
Soil Type or Classification Change
???????
Formation Change [(Approximate boundaries queried (?)]
"SM"Quotes are placed around classifications where the soilsexist in situ as bedrock
FIGURE: BL2
PROJECT:SHEET: of
CTE JOB NO: DRILL METHOD: DRILLING DATE:
LOGGED BY: SAMPLE METHOD: ELEVATION:Depth (Feet)Bulk SampleDriven TypeBlows/6"Dry Density (pcf)Moisture (%)U.S.C.S. SymbolGraphic LogDESCRIPTION
SM
SM
Total Depth: 5.7' (Refusal on gravel)Seepage Encountered at Approximatly 5'
1
10-14444G HAND AUGER 8/7/2018
BUCCOLA RESIDENCE DRILLER: AJB 1
AJB BULK ~14 FEET
BORING: B-1 Laboratory Tests
QUATERNARY SLOPE WASH:Loose, moist to very moist, reddish brown, silty fine to mediumgrained SAND.
QUATERNARY OLD PARALIC DEPOSITS:Medium dense, moist, reddish brown, silty fine to medium grainedSAND, oxidized, massive.
Fine gravelSeepageTERTIARY SANTIAGO FORMATION:Dense to very dense, slightly moist, light gray, silty fine grainedSANDSTONE with trace gravel.
B-1
0
5
10
15
20
25
PROJECT:SHEET: of
CTE JOB NO: DRILL METHOD: DRILLING DATE:
LOGGED BY: SAMPLE METHOD: ELEVATION:Depth (Feet)Bulk SampleDriven TypeBlows/6"Dry Density (pcf)Moisture (%)U.S.C.S. SymbolGraphic LogDESCRIPTION
SM
SM
Total Depth: 5.1' (Refusal in dense formational material)No Groundwater Encountered
B-1A
Dense to very dense, slightly moist, light gray, silty fine grainedSANDSTONE with trace gravel.
TERTIARY SANTIAGO FORMATION:
Medium dense, moist, reddish brown, silty fine to medium grainedSAND, oxidized, massive.
grained SAND.
QUATERNARY OLD PARALIC DEPOSITS:
QUATERNARY SLOPE WASH:Loose, moist, reddish brown, silty fine to medium
AJB BULK ~14 FEET
BORING: B-1A Laboratory Tests
BUCCOLA RESIDENCE DRILLER:AJB 1 1
10-14444G HAND AUGER 8/7/2018
0
5
10
15
20
25
PROJECT:SHEET: of
CTE JOB NO: DRILL METHOD: DRILLING DATE:
LOGGED BY: SAMPLE METHOD: ELEVATION:Depth (Feet)Bulk SampleDriven TypeBlows/6"Dry Density (pcf)Moisture (%)U.S.C.S. SymbolGraphic LogDESCRIPTION
SC/SM
SM
6
7
12
14
SM/SP
4
12
20
16
51
Total Depth: 20'No Groundwater Encountered
B-2
Dense to very dense, slightly moist, light gray, silty fine grainedSANDSTONE with trace gravel.
MD, DS
TERTIARY SANTIAGO FORMATION:
Becomes light gray with abundant medium grained sand.
GS
MD, DS
Medium dense, moist, light reddish brown, silty fine to mediumgrained SAND, oxidized, massive, friable.MD
grained SAND, oxidized, massive.
QUATERNARY OLD PARALIC DEPOSITS:Medium dense, moist, reddish brown, clayey to silty fine to medium
AJB RING, SPT and BULK ~30 FEET
BORING: B-2 Laboratory Tests
BUCCOLA RESIDENCE DRILLER:MANSOFF DRILLING 1 1
10-14444G SOLID-STEM AUGER 8/7/2018
0
5
10
15
20
25
PROJECT:SHEET: of
CTE JOB NO: DRILL METHOD: DRILLING DATE:
LOGGED BY: SAMPLE METHOD: ELEVATION:Depth (Feet)Bulk SampleDriven TypeBlows/6"Dry Density (pcf)Moisture (%)U.S.C.S. SymbolGraphic LogDESCRIPTION
SC/SM
SC
7
7
8
SM
10
15
SM/SP
10
12
16
15
30
30/4"
Total Depth: 19.9'No Groundwater Encountered
B-3
GS, CHEM
Becomes light gray with abundant medium grained sand.
MD
medium grained SAND, oxidized, massive, friable.Medium dense, slightly moist, light reddish brown, silty fine to
grained SAND, oxidized, massive.
QUATERNARY OLD PARALIC DEPOSITS:Medium dense, slighly moist, reddish brown, clayey fine to medium
fine to medium graiend SAND.
EI
RESIDUAL SOIL:Loose to medium dense, slightly moist, dark brown, silty to clayey
AJB RING, SPT and BULK ~37 FEET
BORING: B-3 Laboratory Tests
BUCCOLA RESIDENCE DRILLER:MANSOFF DRILLING 1 1
10-14444G SOLID-STEM AUGER 8/7/2018
0
5
10
15
20
25
APPENDIX C
LABORATORY METHODS AND RESULTS
LABORATORY METHODS AND RESULTS
Laboratory Testing Program
Laboratory tests were performed on representative soil samples to detect their relative engineering
properties. Tests were performed following test methods of the American Society for Testing
Materials or other accepted standards. The following presents a brief description of the various test
methods used.
Classification
Soils were classified visually according to the Unified Soil Classification System. Visual
classifications were supplemented by laboratory testing of selected samples according to ASTM
D2487. The soil classifications are shown on the Exploration Logs in Appendix B.
In-Place Moisture and Density
To determine the moisture and density of in-place site soils, a representative sample was tested
for the moisture and density at time of sampling.
Modified Proctor
Laboratory maximum dry density and optimum moisture content were evaluated according to ASTM
D 1557, Method A. A mechanically operated rammer was used during the compaction process.
Particle-Size Analysis
Particle-size analyses were performed on selected representative samples according to ASTM D 422.
Consolidation
To assess their compressibility and volume change behavior when loaded and wetted, relatively
undisturbed samples of representative samples from the investigation were subject to consolidation
tests in accordance with ASTM D 2435.
Chemical Analysis
Soil materials were collected with sterile sampling equipment and tested for Sulfate and Chloride
content, pH, Corrosivity, and Resistivity.
LOCATION EXPANSION INDEX EXPANSION
POTENTIAL
B-3 3VERY LOW
LOCATION % MOISTURE DRY DENSITY
B-2 4.0 98.0
B-2 5.0 91.4
B-2 18.5 108.6
B-3 5.4 106.0
LOCATION RESULTS
ppm
B-2 501
LOCATION RESULTS
ppm
B-2 440.9
LOCATION RESULTS
B-2 7.26
LOCATION RESULTS
ohms-cm
B-2 28870-15
RESISTIVITY
CALIFORNIA TEST 643
DEPTH
(feet)
CALIFORNIA TEST 643
DEPTH
(feet)
0-15
p.H.
CHLORIDE
CALIFORNIA TEST 422
DEPTH
(feet)
0-15
SULFATE
CALIFORNIA TEST 417
DEPTH
(feet)
0-15
DEPTH
(feet)
5
10
19
10.5
EXPANSION INDEX TEST
ASTM D 4829
DEPTH
(feet)
0-5
IN-PLACE MOISTURE AND DENSITY
LABORATORY SUMMARY CTE JOB NO. 10-14444G
PARTICLE SIZE ANALYSISSample Designation Sample Depth (feet) Symbol Liquid Limit (%) Plasticity Index ClassificationB-215-- SM/SPB-315-- SM/SPCTE JOB NUMBER: 10-14444GFIGURE: C-101020304050607080901000.0010.010.1110100PERCENT PASSING (%)PARTICLE SIZE (mm)U. S. STANDARD SIEVE SIZE2"1"3/4"1/2"3/8"481016203040501002001.5"
SHEAR STRENGTH TEST - ASTM D3080
Job Name:
Project Number:10-14444G
Lab Number:28723
Sample Location:Tested by:
Sample Description:
RCV
8/15/2018
Angle Of Friction:38.0
Cohesion:
Buccola Residence Addition
100 psf
Initial Dry Density (pcf):91.4
Initial Moisture (%):5.0
Final Moisture (%):28.3
B-2 @ 10'
Sample Date:
Test Date:
8/7/2018
light brown SW
0.038
0.038
0.039
0.039
0.040
0.040
0.1 1 10 100STRAIN (inches) TIME (minutes)
PRECONSOLIDATION
0
1000
2000
3000
4000
5000
0 2 4 6 8 10 12 14 16 18 20SHEAR STRESS (psf) STRAIN (%)
SHEARING DATA
0
1000
2000
3000
4000
5000
0 1000 2000 3000 4000 5000SHEARING STRESS (psf) VERTICAL STRESS (psf)
FAILURE ENVELOPE
dr=0.1200 mm./min
VERTICAL STRESS
1000 psf 3000 psf 5000 psf
SHEAR STRENGTH TEST - ASTM D3080
Job Name:
Project Number: 10-14444G
Lab Number: 28723
Sample Location: Tested by:
Sample Description:
RCV
8/14/2018
Angle Of Friction: 43.3
Cohesion:
Buccola Residence Addition
130 psf
Initial Dry Density (pcf): 18.5
Initial Moisture (%): 108.6
Final Moisture (%): 19.5
B-2 @ 19'
Sample Date:
Test Date:
8/7/2018
Light brown SW-SM
0.034
0.034
0.035
0.035
0.036
0.036
0.037
0.1 1 10 100STRAIN (inches)TIME (minutes)
PRECONSOLIDATION
0
1000
2000
3000
4000
5000
02468101214161820SHEAR STRESS (psf)STRAIN (%)
SHEARING DATA
0
1000
2000
3000
4000
5000
0 1000 2000 3000 4000 5000SHEARING STRESS (psf)VERTICAL STRESS (psf)
FAILURE ENVELOPE
dr=0.1200 mm./min
VERTICAL STRESS
1000 psf
3000 psf
5000 psf
APPENDIX D
STANDARD SPECIFICATIONS FOR GRADING
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 1 of 26
Page D-1
Section 1 - General
Construction Testing & Engineering, Inc. presents the following standard recommendations for
grading and other associated operations on construction projects. These guidelines should be
considered a portion of the project specifications. Recommendations contained in the body of
the previously presented soils report shall supersede the recommendations and or requirements as
specified herein. The project geotechnical consultant shall interpret disputes arising out of
interpretation of the recommendations contained in the soils report or specifications contained
herein.
Section 2 - Responsibilities of Project Personnel
The geotechnical consultant should provide observation and testing services sufficient to general
conformance with project specifications and standard grading practices. The geotechnical
consultant should report any deviations to the client or his authorized representative.
The Client should be chiefly responsible for all aspects of the project. He or his authorized
representative has the responsibility of reviewing the findings and recommendations of the
geotechnical consultant. He shall authorize or cause to have authorized the Contractor and/or
other consultants to perform work and/or provide services. During grading the Client or his
authorized representative should remain on-site or should remain reasonably accessible to all
concerned parties in order to make decisions necessary to maintain the flow of the project.
The Contractor is responsible for the safety of the project and satisfactory completion of all
grading and other associated operations on construction projects, including, but not limited to,
earth work in accordance with the project plans, specifications and controlling agency
requirements.
Section 3 - Preconstruction Meeting
A preconstruction site meeting should be arranged by the owner and/or client and should include
the grading contractor, design engineer, geotechnical consultant, owner’s representative and
representatives of the appropriate governing authorities.
Section 4 - Site Preparation
The client or contractor should obtain the required approvals from the controlling authorities for
the project prior, during and/or after demolition, site preparation and removals, etc. The
appropriate approvals should be obtained prior to proceeding with grading operations.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 2 of 26
Page D-2
Clearing and grubbing should consist of the removal of vegetation such as brush, grass, woods,
stumps, trees, root of trees and otherwise deleterious natural materials from the areas to be
graded. Clearing and grubbing should extend to the outside of all proposed excavation and fill
areas.
Demolition should include removal of buildings, structures, foundations, reservoirs, utilities
(including underground pipelines, septic tanks, leach fields, seepage pits, cisterns, mining shafts,
tunnels, etc.) and other man-made surface and subsurface improvements from the areas to be
graded. Demolition of utilities should include proper capping and/or rerouting pipelines at the
project perimeter and cutoff and capping of wells in accordance with the requirements of the
governing authorities and the recommendations of the geotechnical consultant at the time of
demolition.
Trees, plants or man-made improvements not planned to be removed or demolished should be
protected by the contractor from damage or injury.
Debris generated during clearing, grubbing and/or demolition operations should be wasted from
areas to be graded and disposed off-site. Clearing, grubbing and demolition operations should be
performed under the observation of the geotechnical consultant.
Section 5 - Site Protection
Protection of the site during the period of grading should be the responsibility of the contractor.
Unless other provisions are made in writing and agreed upon among the concerned parties,
completion of a portion of the project should not be considered to preclude that portion or
adjacent areas from the requirements for site protection until such time as the entire project is
complete as identified by the geotechnical consultant, the client and the regulating agencies.
Precautions should be taken during the performance of site clearing, excavations and grading to
protect the work site from flooding, ponding or inundation by poor or improper surface drainage.
Temporary provisions should be made during the rainy season to adequately direct surface
drainage away from and off the work site. Where low areas cannot be avoided, pumps should be
kept on hand to continually remove water during periods of rainfall.
Rain related damage should be considered to include, but may not be limited to, erosion, silting,
saturation, swelling, structural distress and other adverse conditions as determined by the
geotechnical consultant. Soil adversely affected should be classified as unsuitable materials and
should be subject to overexcavation and replacement with compacted fill or other remedial
grading as recommended by the geotechnical consultant.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 3 of 26
Page D-3
The contractor should be responsible for the stability of all temporary excavations.
Recommendations by the geotechnical consultant pertaining to temporary excavations (e.g.,
backcuts) are made in consideration of stability of the completed project and, therefore, should
not be considered to preclude the responsibilities of the contractor. Recommendations by the
geotechnical consultant should not be considered to preclude requirements that are more
restrictive by the regulating agencies. The contractor should provide during periods of extensive
rainfall plastic sheeting to prevent unprotected slopes from becoming saturated and unstable.
When deemed appropriate by the geotechnical consultant or governing agencies the contractor
shall install checkdams, desilting basins, sand bags or other drainage control measures.
In relatively level areas and/or slope areas, where saturated soil and/or erosion gullies exist to
depths of greater than 1.0 foot; they should be overexcavated and replaced as compacted fill in
accordance with the applicable specifications. Where affected materials exist to depths of 1.0
foot or less below proposed finished grade, remedial grading by moisture conditioning in-place,
followed by thorough recompaction in accordance with the applicable grading guidelines herein
may be attempted. If the desired results are not achieved, all affected materials should be
overexcavated and replaced as compacted fill in accordance with the slope repair
recommendations herein. If field conditions dictate, the geotechnical consultant may
recommend other slope repair procedures.
Section 6 - Excavations
6.1 Unsuitable Materials
Materials that are unsuitable should be excavated under observation and
recommendations of the geotechnical consultant. Unsuitable materials include, but may
not be limited to, dry, loose, soft, wet, organic compressible natural soils and fractured,
weathered, soft bedrock and nonengineered or otherwise deleterious fill materials.
Material identified by the geotechnical consultant as unsatisfactory due to its moisture
conditions should be overexcavated; moisture conditioned as needed, to a uniform at or
above optimum moisture condition before placement as compacted fill.
If during the course of grading adverse geotechnical conditions are exposed which were
not anticipated in the preliminary soil report as determined by the geotechnical consultant
additional exploration, analysis, and treatment of these problems may be recommended.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 4 of 26
Page D-4
6.2 Cut Slopes
Unless otherwise recommended by the geotechnical consultant and approved by the
regulating agencies, permanent cut slopes should not be steeper than 2:1 (horizontal:
vertical).
The geotechnical consultant should observe cut slope excavation and if these excavations
expose loose cohesionless, significantly fractured or otherwise unsuitable material, the
materials should be overexcavated and replaced with a compacted stabilization fill. If
encountered specific cross section details should be obtained from the Geotechnical
Consultant.
When extensive cut slopes are excavated or these cut slopes are made in the direction of
the prevailing drainage, a non-erodible diversion swale (brow ditch) should be provided
at the top of the slope.
6.3 Pad Areas
All lot pad areas, including side yard terrace containing both cut and fill materials,
transitions, located less than 3 feet deep should be overexcavated to a depth of 3 feet and
replaced with a uniform compacted fill blanket of 3 feet. Actual depth of overexcavation
may vary and should be delineated by the geotechnical consultant during grading,
especially where deep or drastic transitions are present.
For pad areas created above cut or natural slopes, positive drainage should be established
away from the top-of-slope. This may be accomplished utilizing a berm drainage swale
and/or an appropriate pad gradient. A gradient in soil areas away from the top-of-slopes
of 2 percent or greater is recommended.
Section 7 - Compacted Fill
All fill materials should have fill quality, placement, conditioning and compaction as specified
below or as approved by the geotechnical consultant.
7.1 Fill Material Quality
Excavated on-site or import materials which are acceptable to the geotechnical consultant
may be utilized as compacted fill, provided trash, vegetation and other deleterious
materials are removed prior to placement. All import materials anticipated for use on-site
should be sampled tested and approved prior to and placement is in conformance with the
requirements outlined.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 5 of 26
Page D-5
Rocks 12 inches in maximum and smaller may be utilized within compacted fill provided
sufficient fill material is placed and thoroughly compacted over and around all rock to
effectively fill rock voids. The amount of rock should not exceed 40 percent by dry
weight passing the 3/4-inch sieve. The geotechnical consultant may vary those
requirements as field conditions dictate.
Where rocks greater than 12 inches but less than four feet of maximum dimension are
generated during grading, or otherwise desired to be placed within an engineered fill,
special handling in accordance with the recommendations below. Rocks greater than
four feet should be broken down or disposed off-site.
7.2 Placement of Fill
Prior to placement of fill material, the geotechnical consultant should observe and
approve the area to receive fill. After observation and approval, the exposed ground
surface should be scarified to a depth of 6 to 8 inches. The scarified material should be
conditioned (i.e. moisture added or air dried by continued discing) to achieve a moisture
content at or slightly above optimum moisture conditions and compacted to a minimum
of 90 percent of the maximum density or as otherwise recommended in the soils report or
by appropriate government agencies.
Compacted fill should then be placed in thin horizontal lifts not exceeding eight inches in
loose thickness prior to compaction. Each lift should be moisture conditioned as needed,
thoroughly blended to achieve a consistent moisture content at or slightly above optimum
and thoroughly compacted by mechanical methods to a minimum of 90 percent of
laboratory maximum dry density. Each lift should be treated in a like manner until the
desired finished grades are achieved.
The contractor should have suitable and sufficient mechanical compaction equipment and
watering apparatus on the job site to handle the amount of fill being placed in
consideration of moisture retention properties of the materials and weather conditions.
When placing fill in horizontal lifts adjacent to areas sloping steeper than 5:1 (horizontal:
vertical), horizontal keys and vertical benches should be excavated into the adjacent slope
area. Keying and benching should be sufficient to provide at least six-foot wide benches
and a minimum of four feet of vertical bench height within the firm natural ground, firm
bedrock or engineered compacted fill. No compacted fill should be placed in an area
after keying and benching until the geotechnical consultant has reviewed the area.
Material generated by the benching operation should be moved sufficiently away from
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 6 of 26
Page D-6
the bench area to allow for the recommended review of the horizontal bench prior to
placement of fill.
Within a single fill area where grading procedures dictate two or more separate fills,
temporary slopes (false slopes) may be created. When placing fill adjacent to a false
slope, benching should be conducted in the same manner as above described. At least a
3-foot vertical bench should be established within the firm core of adjacent approved
compacted fill prior to placement of additional fill. Benching should proceed in at least
3-foot vertical increments until the desired finished grades are achieved.
Prior to placement of additional compacted fill following an overnight or other grading
delay, the exposed surface or previously compacted fill should be processed by
scarification, moisture conditioning as needed to at or slightly above optimum moisture
content, thoroughly blended and recompacted to a minimum of 90 percent of laboratory
maximum dry density. Where unsuitable materials exist to depths of greater than one
foot, the unsuitable materials should be over-excavated.
Following a period of flooding, rainfall or overwatering by other means, no additional fill
should be placed until damage assessments have been made and remedial grading
performed as described herein.
Rocks 12 inch in maximum dimension and smaller may be utilized in the compacted fill
provided the fill is placed and thoroughly compacted over and around all rock. No
oversize material should be used within 3 feet of finished pad grade and within 1 foot of
other compacted fill areas. Rocks 12 inches up to four feet maximum dimension should
be placed below the upper 10 feet of any fill and should not be closer than 15 feet to any
slope face. These recommendations could vary as locations of improvements dictate.
Where practical, oversized material should not be placed below areas where structures or
deep utilities are proposed. Oversized material should be placed in windrows on a clean,
overexcavated or unyielding compacted fill or firm natural ground surface. Select native
or imported granular soil (S.E. 30 or higher) should be placed and thoroughly flooded
over and around all windrowed rock, such that voids are filled. Windrows of oversized
material should be staggered so those successive strata of oversized material are not in
the same vertical plane.
It may be possible to dispose of individual larger rock as field conditions dictate and as
recommended by the geotechnical consultant at the time of placement.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 7 of 26
Page D-7
The contractor should assist the geotechnical consultant and/or his representative by
digging test pits for removal determinations and/or for testing compacted fill. The
contractor should provide this work at no additional cost to the owner or contractor's
client.
Fill should be tested by the geotechnical consultant for compliance with the
recommended relative compaction and moisture conditions. Field density testing should
conform to ASTM Method of Test D 1556-00, D 2922-04. Tests should be conducted at
a minimum of approximately two vertical feet or approximately 1,000 to 2,000 cubic
yards of fill placed. Actual test intervals may vary as field conditions dictate. Fill found
not to be in conformance with the grading recommendations should be removed or
otherwise handled as recommended by the geotechnical consultant.
7.3 Fill Slopes
Unless otherwise recommended by the geotechnical consultant and approved by the
regulating agencies, permanent fill slopes should not be steeper than 2:1 (horizontal:
vertical).
Except as specifically recommended in these grading guidelines compacted fill slopes
should be over-built two to five feet and cut back to grade, exposing the firm, compacted
fill inner core. The actual amount of overbuilding may vary as field conditions dictate. If
the desired results are not achieved, the existing slopes should be overexcavated and
reconstructed under the guidelines of the geotechnical consultant. The degree of
overbuilding shall be increased until the desired compacted slope surface condition is
achieved. Care should be taken by the contractor to provide thorough mechanical
compaction to the outer edge of the overbuilt slope surface.
At the discretion of the geotechnical consultant, slope face compaction may be attempted
by conventional construction procedures including backrolling. The procedure must
create a firmly compacted material throughout the entire depth of the slope face to the
surface of the previously compacted firm fill intercore.
During grading operations, care should be taken to extend compactive effort to the outer
edge of the slope. Each lift should extend horizontally to the desired finished slope
surface or more as needed to ultimately established desired grades. Grade during
construction should not be allowed to roll off at the edge of the slope. It may be helpful
to elevate slightly the outer edge of the slope. Slough resulting from the placement of
individual lifts should not be allowed to drift down over previous lifts. At intervals not
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 8 of 26
Page D-8
exceeding four feet in vertical slope height or the capability of available equipment,
whichever is less, fill slopes should be thoroughly dozer trackrolled.
For pad areas above fill slopes, positive drainage should be established away from the
top-of-slope. This may be accomplished using a berm and pad gradient of at least two
percent.
Section 8 - Trench Backfill
Utility and/or other excavation of trench backfill should, unless otherwise recommended, be
compacted by mechanical means. Unless otherwise recommended, the degree of compaction
should be a minimum of 90 percent of the laboratory maximum density.
Within slab areas, but outside the influence of foundations, trenches up to one foot wide and two
feet deep may be backfilled with sand and consolidated by jetting, flooding or by mechanical
means. If on-site materials are utilized, they should be wheel-rolled, tamped or otherwise
compacted to a firm condition. For minor interior trenches, density testing may be deleted or
spot testing may be elected if deemed necessary, based on review of backfill operations during
construction.
If utility contractors indicate that it is undesirable to use compaction equipment in close
proximity to a buried conduit, the contractor may elect the utilization of light weight mechanical
compaction equipment and/or shading of the conduit with clean, granular material, which should
be thoroughly jetted in-place above the conduit, prior to initiating mechanical compaction
procedures. Other methods of utility trench compaction may also be appropriate, upon review of
the geotechnical consultant at the time of construction.
In cases where clean granular materials are proposed for use in lieu of native materials or where
flooding or jetting is proposed, the procedures should be considered subject to review by the
geotechnical consultant. Clean granular backfill and/or bedding are not recommended in slope
areas.
Section 9 - Drainage
Where deemed appropriate by the geotechnical consultant, canyon subdrain systems should be
installed in accordance with CTE’s recommendations during grading.
Typical subdrains for compacted fill buttresses, slope stabilization or sidehill masses, should be
installed in accordance with the specifications.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 9 of 26
Page D-9
Roof, pad and slope drainage should be directed away from slopes and areas of structures to
suitable disposal areas via non-erodible devices (i.e., gutters, downspouts, and concrete swales).
For drainage in extensively landscaped areas near structures, (i.e., within four feet) a minimum
of 5 percent gradient away from the structure should be maintained. Pad drainage of at least 2
percent should be maintained over the remainder of the site.
Drainage patterns established at the time of fine grading should be maintained throughout the life
of the project. Property owners should be made aware that altering drainage patterns could be
detrimental to slope stability and foundation performance.
Section 10 - Slope Maintenance
10.1 - Landscape Plants
To enhance surficial slope stability, slope planting should be accomplished at the
completion of grading. Slope planting should consist of deep-rooting vegetation
requiring little watering. Plants native to the southern California area and plants relative
to native plants are generally desirable. Plants native to other semi-arid and arid areas
may also be appropriate. A Landscape Architect should be the best party to consult
regarding actual types of plants and planting configuration.
10.2 - Irrigation
Irrigation pipes should be anchored to slope faces, not placed in trenches excavated into
slope faces.
Slope irrigation should be minimized. If automatic timing devices are utilized on
irrigation systems, provisions should be made for interrupting normal irrigation during
periods of rainfall.
10.3 - Repair
As a precautionary measure, plastic sheeting should be readily available, or kept on hand,
to protect all slope areas from saturation by periods of heavy or prolonged rainfall. This
measure is strongly recommended, beginning with the period prior to landscape planting.
If slope failures occur, the geotechnical consultant should be contacted for a field review
of site conditions and development of recommendations for evaluation and repair.
If slope failures occur as a result of exposure to period of heavy rainfall, the failure areas
and currently unaffected areas should be covered with plastic sheeting to protect against
additional saturation.
Appendix D
Standard Specifications for Grading
STANDARD SPECIFICATIONS OF GRADING
Page 10 of 26
Page D-10
In the accompanying Standard Details, appropriate repair procedures are illustrated for
superficial slope failures (i.e., occurring typically within the outer one foot to three feet of
a slope face).
APPENDIX E
SLOPE/W OUTPUT
20ELEVATION (FEET)100DISTANCE (FEET)CROSS SECTION A-A'0500-10-20101502003040-30200-10-20103040-30AA'Proj.~5' NTD=5.7'TD=20.0'TD=19.9'B-1Proj.~15' SB-3B-2QopTsaResidual SoilRip RapQmbExisting Profile123456123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354552.11112345678910111213141516171819202122232425262728293031323334353637383940414243444546474849505152535455Description: QmbModel: MohrCoulombWt: 120Cohesion: 0Phi: 37Piezometric Line: 1Description: Rip RapModel: MohrCoulombWt: 140Cohesion: 100Phi: 45Piezometric Line: 1Description: Residual SoilModel: MohrCoulombWt: 120Cohesion: 400Phi: 35Piezometric Line: 1Description: QswModel: MohrCoulombWt: 120Cohesion: 250Phi: 37Piezometric Line: 1Description: QopModel: MohrCoulombWt: 120Cohesion: 100Phi: 38Piezometric Line: 1Description: TsaModel: MohrCoulombWt: 120Cohesion: 500Phi: 38Piezometric Line: 1Name: Entry Exit.gszMethod: SpencerDirection of movement: RightToLeftSlip Surface Option: EntryAndExitHorz Seismic Load: 0Vert Seismic Load: 0Factor of Safety: 2.111
APPENDIX F
PERCOLATION TO INFILTRATION CALCULATIONS AND FIELD DATA
CHANGE YELLOW ONLYAsk RJ QuestionsJob Name:Buccola ResidenceJob No.:10‐14444GTest Hole Name:P‐1Time Test Interval TimeTest RefillWater Level Initial/StartWater Level End/FinalIncremental Water Level ChangePercolation RatePercolation Rate(minutes) Feet InchesInches Depth /Inches Feet InchesDepth /Inches (inches) inches/minute inches/hourStart Time:12:20 12:20 PM Initial 3 10 7 / 8 46.875 46.875 3 10 7 / 8 initial‐Reading Increment (min): 0:10 12:30 PM10 3 10 7 / 8 46.875 46.875 4 1 1 / 4 49.250 2.3750 0.238 14.250Total Depth:63 12:40 PM10 3 10 0 / 16 46.000 46.875 4 1 5 / 8 49.625 2.7500 0.275 16.500Test Hole Radius (in):3 12:50 PM10 3 9 1 / 2 45.500 46.000 4 1 1 / 4 49.250 3.2500 0.325 19.500Test Hole Diameter (in):6 1:00 PM10 3 9 1 / 2 45.500 45.500 4 0 1 / 4 48.250 2.7500 0.275 16.5001:10 PM10 3 9 1 / 2 45.500 45.500 4 0 0 / 16 48.000 2.5000 0.250 15.0001:20 PM10 0 0 0 / 16 NO 45.500 4 0 0 / 16 48.000 2.5000 0.250 15.000P‐2Time Test Interval TimeTest RefillWater Level Initial/StartWater Level End/FinalIncremental Water Level ChangePercolation RatePercolation Rate(minutes) Feet InchesInches Depth /Inches Feet InchesDepth /Inches (inches) inches/minute inches/hourStart Time:12:22 12:22 PM Initial 2 5 0 / 16 29.000 29.000 2 5 0 / 16 initial‐Reading Increment (min): 0:10 12:32 PM10 2 5 0 / 16 29.000 29.000 2 8 5 / 8 32.625 3.625 0.363 21.750Total Depth:37 12:42 PM10 2 5 0 / 16 29.000 29.000 2 8 3 / 8 32.375 3.375 0.338 20.250Test Hole Radius (in):3 12:52 PM10 2 5 0 / 16 29.000 29.000 2 8 1 / 2 32.500 3.500 0.350 21.000Test Hole Diameter (in):6 1:02 PM10 2 4 3 / 4 28.750 29.000 2 9 1 / 4 33.250 4.250 0.425 25.5001:12 PM10 2 4 5 / 8 28.625 28.750 2 8 0 / 16 32.000 3.250 0.325 19.5001:22 PM10 0 0 0 / 16 NO 28.625 2 8 0 / 16 32.000 3.375 0.338 20.250FractionFractionFractionTest Refill InputFractionWater Level Final DepthWater Level Final DepthTest Refill Input
APPENDIX G
I-8 WORKSHEET
I-8
I-8
X
The NRCS soil mapped at the soil consists of a Type B soil with medium surface runoff. The site
soils are consistent with the NRCS mapped soil types based on site explorations and percolation
testing. Three soil types were present in the area of the proposed improvements, Residual Soil,
Quaternary Old Paralic Deposits and Tertiary Santiago Formation.
Two percolation tests were completed within the Old Paralic Deposits. The calculated infiltration
rates (with an applied factor of safety of 2) ranged from approximately 0.63 to 1.85 inches per
hour.
X
Any water infiltrating on the western portion of the site would likely migrate to and discharge
from the existing slope face and could result in piping, oversteepening and destabilizing the slope.
I-8
I-8 X
According to Geotracker, the nearest known "Open" LUST cleanup site is over 2,000 feet away
from the site.
X
The nearest down gradient surface waters are the Pacific Ocean which is located at the base of the
existing site slope. Due to the close proximity of the Pacific Ocean infiltrating water could
potentially have a impact.
No Full
I-8
X
Based on the working draft version of Appendix C, it is CTE's understanding that the lower limit
of partial infiltration is 0.05 inches/hour. Which is less than the rate that was determined by
testing therefore partial infiltration is possible.
X
Any water infiltrating on the western portion of the site would likely migrate to and discharge
from the existing slope face and could result in piping, oversteepening and destabilizing the slope.
I-8
X
According to Geotracker, the nearest known "Open" LUST cleanup site is over 2,000 feet away
from the site.
X
The nearest down gradient surface waters are the Pacific Ocean which is located at the base of the
existing site slope. Due to the close proximity of the Pacific Ocean infiltrating water could
potentially have a impact.
No Inf.
APPENDIX H
HISTORIC TOPOGRAPHIC MAPS
EDR Historical Topo Map Report
Inquiry Number:
6 Armstrong Road, 4th floor
Shelton, CT 06484
Toll Free: 800.352.0050 www.edrnet.com
with QuadMatch™
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
August 24, 2018
5404232.1
EDR Historical Topo Map Report
EDR Inquiry #
Search Results:
P.O.#
Project:
Maps Provided:
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EDR and its logos (including Sanborn and Sanborn Map) are trademarks of Environmental Data Resources, Inc. or its affiliates. All other trademarks used herein
are the property of their respective owners.
page-
Coordinates:
Latitude:
Longitude:
UTM Zone:
UTM X Meters:
UTM Y Meters:
Elevation:
Contact:
Site Name: Client Name:
2012
1997
1975
1968
1949
1948
1947
1901
1898
1893
08/24/18
Buccola Residence Addition Construction Testing & Eng.
5031 Tierra Del Oro 1441 Montiel Rd
Carlsbad, CA 92008 Escondido, CA 92026
5404232.1 Brandon Alderson
EDR Topographic Map Library has been searched by EDR and maps covering the target property location as provided by
Construction Testing & Eng. were identified for the years listed below. EDR’s Historical Topo Map Report is designed to
assist professionals in evaluating potential liability on a target property resulting from past activities. EDRs Historical Topo
Map Report includes a search of a collection of public and private color historical topographic maps, dating back to the late
1800s.
10-14444G 33.132212 33° 7' 56" North
Buccola Residence Addition -117.336702 -117° 20' 12" West
Zone 11 North
468593.62
3665994.57
23.80' above sea level
This Report contains certain information obtained from a variety of public and other sources reasonably available to Environmental Data Resources, Inc. It cannot
be concluded from this Report that coverage information for the target and surrounding properties does not exist from other sources. NO WARRANTY
EXPRESSED OR IMPLIED, IS MADE WHATSOEVER IN CONNECTION WITH THIS REPORT. ENVIRONMENTAL DATA RESOURCES, INC. SPECIFICALLY
DISCLAIMS THE MAKING OF ANY SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE
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WHETHER ARISING OUT OF ERRORS OR OMISSIONS, NEGLIGENCE, ACCIDENT OR ANY OTHER CAUSE, FOR ANY LOSS OF DAMAGE, INCLUDING,
WITHOUT LIMITATION, SPECIAL, INCIDENTAL, CONSEQUENTIAL, OR EXEMPLARY DAMAGES. ANY LIABILITY ON THE PART OF ENVIRONMENTAL
DATA RESOURCES, INC. IS STRICTLY LIMITED TO A REFUND OF THE AMOUNT PAID FOR THIS REPORT. Purchaser accepts this Report "AS IS". Any
analyses, estimates, ratings, environmental risk levels or risk codes provided in this Report are provided for illustrative purposes only, and are not intended to
provide, nor should they be interpreted as providing any facts regarding, or prediction or forecast of, any environmental risk for any property. Only a Phase I
Environmental Site Assessment performed by an environmental professional can provide information regarding the environmental risk for any property.
Additionally, the information provided in this Report is not to be construed as legal advice.
Copyright 2018 by Environmental Data Resources, Inc. All rights reserved. Reproduction in any media or format, in whole or in part, of any report or map of
Environmental Data Resources, Inc., or its affiliates, is prohibited without prior written permission.
5404232 1 2
page
Topo Sheet Key
This EDR Topo Map Report is based upon the following USGS topographic map sheets.
-
2012 Source Sheets
2012
San Luis Rey
7.5-minute, 24000
2012
Encinitas
7.5-minute, 24000
1997 Source Sheets
1997
Encinitas
7.5-minute, 24000
Aerial Photo Revised 1997
1997
San Luis Rey
7.5-minute, 24000
Aerial Photo Revised 1997
1975 Source Sheets
1975
Encinitas
7.5-minute, 24000
Aerial Photo Revised 1975
1975
San Luis Rey
7.5-minute, 24000
Aerial Photo Revised 1975
1968 Source Sheets
1968
Encinitas
7.5-minute, 24000
Aerial Photo Revised 1967
1968
San Luis Rey
7.5-minute, 24000
Aerial Photo Revised 1967
5404232 1 3
page
Topo Sheet Key
This EDR Topo Map Report is based upon the following USGS topographic map sheets.
-
1949 Source Sheets
1949
San Luis Rey
7.5-minute, 24000
Aerial Photo Revised 1946
1949
Encinitas
7.5-minute, 24000
Aerial Photo Revised 1947
1948 Source Sheets
1948
San Luis Rey
7.5-minute, 24000
Aerial Photo Revised 1946
1948
Encinitas
7.5-minute, 24000
Aerial Photo Revised 1947
1947 Source Sheets
1947
OCEANSIDE
15-minute, 50000
1901 Source Sheets
1901
Oceanside
15-minute, 62500
5404232 1 4
page
Topo Sheet Key
This EDR Topo Map Report is based upon the following USGS topographic map sheets.
-
1898 Source Sheets
1898
Oceanside
15-minute, 62500
1893 Source Sheets
1893
Oceanside
15-minute, 62500
5404232 1 5
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
2012
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 2012, 7.5-minute
S, Encinitas, 2012, 7.5-minute
5404232 1 6
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1997
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 1997, 7.5-minute
S, Encinitas, 1997, 7.5-minute
5404232 1 7
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1975
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 1975, 7.5-minute
S, Encinitas, 1975, 7.5-minute
5404232 1 8
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1968
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 1968, 7.5-minute
S, Encinitas, 1968, 7.5-minute
5404232 1 9
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1949
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 1949, 7.5-minute
S, Encinitas, 1949, 7.5-minute
5404232 1 10
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1948
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, San Luis Rey, 1948, 7.5-minute
S, Encinitas, 1948, 7.5-minute
5404232 1 11
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1947
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, OCEANSIDE, 1947, 15-minute
5404232 1 12
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1901
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, Oceanside, 1901, 15-minute
5404232 1 13
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1898
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, Oceanside, 1898, 15-minute
5404232 1 14
Historical Topo Map
page
SITE NAME:
ADDRESS:
CLIENT:
This report includes information from the
following map sheet(s).
-
EW
SW S SE
NW N NE
1893
0 Miles 0.25 0.5 1 1.5
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Construction Testing & Eng.
TP, Oceanside, 1893, 15-minute
5404232 1 15
APPENDIX I
HISTORIC OBLIQUE AERIAL PHOTOGRAPHS FROM
CALIFORNIA COASTAL PROJECT
APPENDIX J
HISTORIC AERIAL PHOTOGRAPHS
The EDR Aerial Photo Decade Package
Buccola Residence Addition
5031 Tierra Del Oro
Carlsbad, CA 92008
Inquiry Number:
August 24, 2018
5404232.2
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2016 1"=500'Flight Year: 2016 USDA/NAIP
2012 1"=500'Flight Year: 2012 USDA/NAIP
2009 1"=500'Flight Year: 2009 USDA/NAIP
2005 1"=500'Flight Year: 2005 USDA/NAIP
1994 1"=500'Acquisition Date: June 01, 1994 USGS/DOQQ
1990 1"=500'Flight Date: September 06, 1990 USDA
1985 1"=500'Flight Date: September 13, 1985 USDA
1979 1"=500'Flight Date: January 27, 1979 EDR Proprietary Landiscor
1970 1"=500'Flight Date: March 06, 1970 EDR Proprietary Landiscor
1967 1"=500'Flight Date: May 07, 1967 USGS
1964 1"=500'Flight Date: April 09, 1964 USDA
1953 1"=500'Flight Date: April 14, 1953 USDA
1946 1"=500'Flight Date: December 30, 1946 USGS
1939 1"=500'Flight Date: April 16, 1939 USDA
1928 1"=500'Flight Date: November 01, 1928 USGS
EDR Aerial Photo Decade Package 08/24/18
Buccola Residence Addition
Site Name:Client Name:
Construction Testing & Eng.
5031 Tierra Del Oro 1441 Montiel Rd
Carlsbad, CA 92008 Escondido, CA 92026
EDR Inquiry #5404232.2 Contact:Brandon Alderson
Environmental Data Resources, Inc. (EDR) Aerial Photo Decade Package is a screening tool designed to assist
environmental professionals in evaluating potential liability on a target property resulting from past activities. EDR’s
professional researchers provide digitally reproduced historical aerial photographs, and when available, provide one photo
per decade.
Search Results:
Year Scale Details Source
When delivered electronically by EDR, the aerial photo images included with this report are for ONE TIME USE
ONLY. Further reproduction of these aerial photo images is prohibited without permission from EDR. For more
information contact your EDR Account Executive.
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5404232 2-page 2
5404232.2
2016
= 500'
5404232.2
2012
= 500'
5404232.2
2009
= 500'
5404232.2
2005
= 500'
5404232.2
1994
= 500'
5404232.2
1990
= 500'
5404232.2
1985
= 500'
5404232.2
1979
= 500'
5404232.2
1928
= 500'
5404232.2
1964
= 500'
5404232.2
1953
= 500'
5404232.2
1946
= 500'
5404232.2
1939
= 500'
5404232.2
1970
= 500'
5404232.2
1967
= 500'