HomeMy WebLinkAboutSDP 2023-0012; LEGOLAND PROJECT 2025; UPDATED GEOTECHNICAL INVESTIGATION FOR LEGOLAND CALIFORNIA PROJECT 2025; 2023-08-09
4373 Viewridge Avenue
Suite B
San Diego, California 92123
858.292.7575
944 Calle Amanecer
Suite F
San Clemente, CA 92673
949.388.7710
usa-nova.com
NOVA Project No. 2022239
August 9, 2023
LEGOLAND California Project 2025
One Legoland Drive, Carlsbad, CA 92008
Merlin Entertainment Group
c/o LEGOLAND California, LLC
One Legoland Drive
Carlsbad, California 92008
UPDATE GEOTECHNICAL INVESTIGATION
----I--I
-~~-
,a~ 1■1
NOVA
Services
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION DVBE SBE SDVOSB SLBE
4373 Viewridge Avenue, Suite B
San Diego, CA 92123
P: 858.292.7575
usa-nova.com 944 Calle Amanecer, Suite F
San Clemente, CA 92673
P: 949.388.7710
Mr. Tom Storer, Senior Project Manager August 9, 2023
Merlin Entertainment Group NOVA Project No. 2022239
c/o LEGOLAND California, LLC
One Legoland Drive
Carlsbad, California 92008
Subject: Update Geotechnical Investigation
LEGOLAND California Project 2025
One Legoland Drive
Carlsbad, CA 92008
Dear Mr. Storer:
NOVA Services, Inc. (NOVA) is pleased to present our report describing the updated geotechnical
investigation performed for the LEGOLAND California Project 2025 project. We conducted the
geotechnical investigation in general conformance with the scope of work presented in our change
order dated May 22, 2023.
This site is considered geotechnically suitable for construction of the proposed improvements provided
the recommendations within this report are followed.
NOVA appreciates the opportunity to be of service to LEGOLAND California, LLC on this project. If
you have any questions regarding this report, please call us at 858.292.7575 x 417.
Sincerely,
NOVA Services, Inc.
_____________________________ _________________________
Gillian Carzzarella Dean, PE C87787 W. Lee Vanderhurst, PG, CEG 1125
Senior Engineer Senior Engineering Geologist
___________________________
Tom Canady, PE, 50057
Principal Engineer
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
i
UPDATE GEOTECHNICAL INVESTIGATION
LEGOLAND California Project 2025
One Legoland Drive, Carlsbad, CA 92008
TABLE OF CONTENTS
1. INTRODUCTION ............................................................................................................ 1
2. SCOPE OF WORK ......................................................................................................... 3
2.1. Field Investigation ...............................................................................................................3
2.2. Laboratory Testing ..............................................................................................................4
2.3. Analysis and Report Preparation .........................................................................................4
3. SITE AND PROJECT DESCRIPTION ........................................................................... 5
3.1. Site Description ...................................................................................................................5
3.2. Site History ..........................................................................................................................5
3.3. Proposed Construction ........................................................................................................5
4. GEOLOGY AND SUBSURFACE CONDITIONS ........................................................... 6
4.1. Site-Specific Geology ..........................................................................................................7
5. GEOLOGIC HAZARDS .................................................................................................. 9
5.1. Faulting and Surface Rupture .............................................................................................9
5.2. Site Class ..........................................................................................................................10
5.3. CBC Seismic Design Parameters......................................................................................10
5.4. Landslides and Slope Stability ..........................................................................................10
5.5. Liquefaction and Dynamic Settlement ...............................................................................10
5.6. Flooding, Tsunamis, and Seiches .....................................................................................11
5.7. Subsidence ........................................................................................................................11
5.8. Hydro-Consolidation ..........................................................................................................11
6. CONCLUSIONS ........................................................................................................... 12
7. RECOMMENDATIONS ................................................................................................ 13
7.1. Earthwork ..........................................................................................................................13
7.1.1 Site Preparation ...................................................................................................13
7.1.2 Remedial Grading – Rollercoaster Building .........................................................13
7.1.3 Remedial Grading – Airboat Ride ........................................................................13
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
ii
7.1.4 Remedial Grading – Pedestrian Hardscape .........................................................14
7.1.5 Remedial Grading – Retaining Walls and Site Walls ...........................................14
7.1.6 Remedial Grading – Vehicular Pavements ..........................................................14
7.1.7 Expansive Soil ......................................................................................................14
7.1.8 Compacted Fill .....................................................................................................14
7.1.9 Imported Soil ........................................................................................................15
7.1.10 Subgrade Stabilization .........................................................................................15
7.1.11 Excavation Characteristics ...................................................................................15
7.1.12 Oversized Material ...............................................................................................15
7.1.13 Temporary Excavations .......................................................................................15
7.1.14 Groundwater Seepage .........................................................................................16
7.1.15 Slopes ..................................................................................................................16
7.1.16 Surface Drainage .................................................................................................16
7.1.17 Grading Plan Review ...........................................................................................16
7.2. Foundations .......................................................................................................................17
7.2.1 Spread Footings ...................................................................................................17
7.2.2 Mat Foundations ..................................................................................................17
7.2.3 CIDH Piles ............................................................................................................18
7.2.4 Settlement Characteristics ...................................................................................18
7.2.5 Foundation Plan Review ......................................................................................18
7.2.6 Foundation Excavation Observations ..................................................................18
7.3. Pedestrian Hardscape .......................................................................................................19
7.4. Conventional Retaining Walls and Site Walls ....................................................................19
7.5. Pavement Section Recommendations ..............................................................................21
7.6. Pipelines ............................................................................................................................21
7.7. Corrosivity .........................................................................................................................22
8. CLOSURE .................................................................................................................... 23
9. REFERENCES ............................................................................................................. 24
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
iii
List of Figures
Figure 1-1. Site Vicinity Map
Figure 1-2. Site Location MAPI
Figure 2-1. Subsurface Exploration Map
Figure 4-1. Regional Geologic Map
Figure 4-2. Fill in Boring B-5
Figure 4-3. Old Paralic Deposits in Boring B-4
Figure 5-1. Regional Faulting in the Site Vicinity
Figure 7-1. Typical Conventional Retaining Wall Backdrain Detail
List of Tables
Table 5-1. 2022 CBC and ASCE 7-16 Seismic Design Parameters
Table 7-1. AC and PCC Pavement Sections
List of Plates
Plate 1 Geotechnical Map
Plate 2 Geologic Cross-Section
List of Appendices
Appendix A Use of the Geotechnical Report
Appendix B Boring Logs
Appendix C Laboratory Testing
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
1
1. INTRODUCTION
This report presents the results of the update geotechnical investigation NOVA performed for the
LEGOLAND California Project 2025 project. We understand the project will consist of the design and
construction of an indoor rollercoaster building, an airboat ride, and associated improvements. The
purpose of our work is to provide conclusions and recommendations regarding the geotechnical
aspects of the project. Figure 1-1 presents a site vicinity map. Figure 1-2 presents a site location map.
Figure 1-1. Site Vicinity Map
Carlsbad
Prem,um
Outlets
Carlsbad
Flower
Fields
p
SITE
\\
... ~ I?
... ' lii
\' ';J., ._,
.. ¾. .... -~--·
'
<-\, '-:
Co
p
.-
,'~tilJ~~c-l
-:...-=
.. ~ " Seobnght -1
512
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
2
Figure 1-2. Site Location Map
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
3
2. SCOPE OF WORK
2.1. Field Investigation
NOVA’s current field investigation (NOVA, 2023) consisted of drilling three geotechnical borings (B-3
through B-5) to depths between about 11½ and 21½ feet below the ground surface (bgs) using a
track-mounted, limited-access drill rig equipped with a solid stem auger and a hand auger. NOVA’s
previous field investigation (NOVA, 2021) consisted of drilling two geotechnical borings (B-1 and B-2)
to depths of about 28½ and 31½ feet bgs using a track-mounted, limited-access drill rig equipped with
a hollow stem auger and a hand auger. Figure 2-1 presents the approximate locations of the borings.
Figure 2-1. Subsurface Exploration Map
A NOVA geologist logged the borings and collected samples of the materials encountered for
laboratory testing. Relatively undisturbed samples were obtained using a modified California (CAL)
sampler, a ring-lined split tube sampler with a 3-inch outer diameter and 2½-inch inner diameter.
Standard Penetration Tests (SPT) were performed in the borings using a 2-inch outer diameter and
1⅜-inch inner diameter split tube sampler. The CAL and SPT samplers in borings B-1 and B-2 were
driven using an automatic hammer with a calibrated Energy Transfer Ratio (ETR) of 88.3%. The CAL
and SPT samplers in borings B-3 through B-5 were driven using an automatic hammer with a
calibrated ETR of 95.7%. The number of blows needed to drive the sampler 18 inches is noted in
B-1 ,8
) J
/1
KEY TO SYMBOLS
B-2 8 GEOTECHNICAL BORING
(NOVA, 2021)
8-5 8
-- --=---~-~~-=-
'-----.J::--"""il.,~,:\
GEOTECHNICAL BORING
(NOVA, 2023)
~ i
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
4
three, 6-inch intervals on the logs. Sampler refusal was encountered when 50 blows were applied
during any one of the three 6-inch intervals, a total of 100 blows was applied, or there was no
discernible sampler advancement during the application of ten successive blows. The field blow
counts, N, were corrected to a standard hammer (cathead and rope) with a 60% ETR. The corrected
blow counts are noted on the boring logs as N60. Disturbed bulk samples were obtained from the SPT
sampler and the drill cuttings. Logs of the borings are presented in Appendix B. Soils are classified
according to the Unified Soil Classification System.
2.2. Laboratory Testing
NOVA tested select samples of the materials encountered to evaluate soil classification and
engineering properties and develop geotechnical conclusions and recommendations. The laboratory
tests consisted of particle-size distribution, Atterberg limits, expansion index, R-value, and corrosivity.
The results of the laboratory tests and brief explanations of the test procedures are presented in
Appendix C.
2.3. Analysis and Report Preparation
The results of the field and laboratory testing were evaluated to develop conclusions and
recommendations regarding the geotechnical aspects of the proposed construction. This report
presents our findings, conclusions, and recommendations.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
5
3. SITE AND PROJECT DESCRIPTION
3.1. Site Description
LEGOLAND California consists of a 128-acre property located at One Legoland Drive in Carlsbad,
California. The Project 2025 site is currently occupied by the Driving School track and facilities. This
area slopes slightly to the south, with elevations ranging from about +160 feet to +166 feet National
Geodetic Vertical Datum of 1929 (NGVD 29). In the southwest corner of the site, a 3-foot slope and
an 8- to 9-foot slope descends towards the service road adjacent to Legoland Drive. In the southeast
corner of the site, a 6-foot slope descends towards the Legoland walking path.
3.2. Site History
Review of historic aerial photography indicates that from at least 1947, the date of the earliest available
imagery, until 1997, the area was used for agricultural purposes. The park’s construction began in
1998 and was completed around 2002. The existing park structures have been in place since the park
was opened. Review of historic topography indicates that prior to LEGOLAND development, the
general area consisted of a natural north-northwest trending ridge that rose to an elevation of about
180 feet NGVD 29 in the east.
The project area consisted of an approximately 20-foot-deep natural drainage swale that extended in
a north-south direction below the western portion of the site, with drainage falling toward the south.
This subtle depression is part of the pre-existing canyon system that drained to the large east-west
canyon just south of Palomar Airport Road. It appears that during the relatively recent grading for
LEGOLAND this depression was filled to create the existing, relatively flat configuration of the area.
The historic topography indicates the eastern part of the site was within the ridge discussed above.
This indicates that the site is likely underlain by a cut/fill transition or transitions from shallow fill to
deep fill.
3.3. Proposed Construction
Based on discussions with the design team and our review of provided plans (RWS, 2023), NOVA
understands the proposed construction will consist of design and construction of an indoor
rollercoaster building, an outdoor airboat ride, an outdoor play structure, and an outdoor tot lot. We
anticipate that foundations for the rollercoaster and enclosure building will consist of shallow spread
footings or cast-in-drilled-hole (CIDH) piles. No below-grade building construction is anticipated. Site
improvements are anticipated to consist of pavement, hardscape, underground utilities, and retaining
walls. The limits of work encompass approximately 85,250 square feet (sf) (RWA, 2023), which
includes the proposed rollercoaster building and associated improvements. Based on our review of
the project plans (CDR, 2023), we understand the proposed site grades will generally match current
grades, and that minor site grading will be required. Earthwork is anticipated to consist of remedial
and fine grading, excavations for foundations, backfilling retaining walls and underground utilities, and
subgrade preparation.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
6
4. GEOLOGY AND SUBSURFACE CONDITIONS
The sites are located within the Peninsular Ranges Geomorphic Province of California, which
stretches from the Los Angeles basin to the tip of Baja California in Mexico. This province is
characterized as a series of northwest-trending mountain ranges separated by subparallel fault zones
and a coastal plain of subdued landforms. The mountain ranges are underlain primarily by Mesozoic
metamorphic rocks that were intruded by plutonic rocks of the western Peninsular Ranges batholith,
while the coastal plain is underlain by subsequently deposited marine and nonmarine sedimentary
formations. The site is located within the coastal plain portion of the province and is underlain by old
paralic deposits. Figure 4-1 presents the regional geology in the vicinity of the site.
Figure 4-1. Regional Geologic Map
(Source: Kennedy and Tan 2007)
KEV TO SYMBOLS
~ ALLUVIAL FLOOD-PLAIN I Qop2-4 I OLD PARALIC DEPOSITS, ~ SANTIAGO FORMATION DEPOSITS UNIT 2-4, UNDIVIDED
I OVOP10 I ~ METAMORPHOSED AND ~ YOUNG ALLUVIAL VERY OLD PARALIC UNMETAMORPHOSED VOLCANIC AND FLOOD-PLAIN DEPOSITS DEPOSITS, UNIT 10 SEDIMENTARY ROCKS, UNDIVIDED
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
7
4.1. Site-Specific Geology
As encountered in the borings, the site is underlain by fill and old paralic deposits. Descriptions of the
materials encountered are presented below. The Geotechnical Map (Plate 1) and Geologic Cross-
Section (Plate 2) following the text of the report present the site-specific geology.
Fill (af): Fill was encountered at the ground surface in borings B-1, B-2, and B-5 and beneath
the existing pavement sections in borings B-3 and B-4 to depths up to about 18 feet bgs. As
encountered in the borings, the fill generally consisted of medium dense to very dense silty
and clayey sand and stiff sandy clay. NOVA has no records regarding the placement and
compaction of the fill; therefore, it is at risk for wide variations in quality. Figure 4-2 presents a
photograph of the fill encountered in Boring B-5.
Figure 4-2. Fill in Boring B-5
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
8
Quaternary Old Paralic Deposits (Qop): Quaternary-aged old paralic deposits were
encountered beneath the fill in the borings and extended to the maximum explored depths of
about 31½ feet. As encountered in the borings, the old paralic deposits consisted of poorly to
moderately cemented, medium dense to very dense silty and clayey sand. Figure 4-3 presents
a photograph of the old paralic deposits encountered in Boring B-4.
Figure 4-3. Old Paralic Deposits in Boring B-4
Groundwater: Groundwater was not encountered in the borings. However, perched groundwater may
be encountered in the future due to rainfall, irrigation, broken pipes, or changes in site drainage.
Because perched groundwater conditions are difficult to predict, such conditions are typically mitigated
if and when they occur.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
9
5. GEOLOGIC HAZARDS
5.1. Faulting and Surface Rupture
The nearest known active fault is the Oceanside section of the Newport-Inglewood-Rose Canyon fault
zone, located about 5 miles to the southwest. The site is not located in the Alquist-Priolo Earthquake
Fault Zone. No active surface faults are mapped across the site. No active faults are known to underlie
or project toward the site. Due to the lack of active faulting, the probability of fault rupture at this site
is considered low. Figure 5-1 presents regional faulting in the site vicinity.
Figure 5-1. Regional Faulting in the Site Vicinity
(Source: Fault Activity Map of California – California Geological Survey)
\ • -\ \\
'~.._,_~i\\
' ~'1
~
\ ~ \ ~ ....
\ \
\ ~
I
1
I
I 1:1,n,,11
\ ~ \ ~ ~
\ ~ \ ~ ~, '"""
' q, 0 ' \ -~ ~~OO~ ~\ 1'~.>-~~ncrn1t••\ -'7
1
'
'% \ ~ \' / •
'I-~ \ ~ i'\1 ) I
<t,,.,Q 1 ~ " -.... " ; ,._. \ ' \ --:. ', \~ / \ / _::_r-Puw"y
' I I
Fault along which . -. KEY TO SYMBOLS •' "'"<""'••or
Late Quaternary~a-:l;;;:-----4
-
years) displac historic (last 200 ement has occurred
Holocene fault d" --------4 (during past 700 ,splacement
11 700 ,splaceme 1 ( 000
-
______ • _ _:Y,~--•l•Ooo<> o °""°°'"" • ~••) ,stone record. p -
------------~Q:u:a:te:rn:a:f:~; ;:-alt uaternary fault (old--------?-ry ault (age und"ff · u without er than 1 6 • : ' erentiated). recognized Quaterna m,U,on years) or ry displacement.
---~
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
10
5.2. Site Class
Site Class is determined by the weighted average of shear-wave velocity or standard penetration
resistance (N-value) within the upper 100 feet of the soil and rock underlying a site. A site underlain
by soil and rock with an average N-value greater than 50 blows per foot within the upper 100 feet is
classified as Site Class C in accordance with Table 20.3-1 of ASCE 7-16. The average penetration
resistances NOVA encountered within the old paralic deposits exceeded 50 blows per foot. Therefore,
the site is classified as Site Class C.
5.3. CBC Seismic Design Parameters
A geologic hazard likely to affect the project is ground shaking caused by movement along an active
fault in the vicinity of the subject site. The site coefficients and maximum considered earthquake
(MCER) spectral response acceleration parameters in accordance with the 2022 California Building
Code (CBC) and ASCE 7-16 are presented in Table 5-1.
Table 5-1. 2022 CBC and ASCE 7-16 Seismic Design Parameters
Site Coordinates
Latitude: 33.12754° Longitude: -117.31376°
Site Coefficients and Spectral Response Acceleration Parameters Value
Site Class C
Site Amplification Factor at 0.2 Second, Fa 1.200
Site Amplification Factor at 1.0 Second, Fv 1.500
Spectral Response Acceleration at Short Period, SS 1.064g
Spectral Response Acceleration at 1-Second Period, S1 0.385g
Spectral Response Acceleration at Short Period, Adjusted for Site Class, SMS 1.277g
Spectral Response Acceleration at 1-Second Period, Adjusted for Site Class, SM1 0.577g
Design Spectral Acceleration at Short Period, SDS 0.851g
Design Spectral Acceleration at 1-Second Period, SD1 0.385g
Peak Ground Acceleration, PGAM 0.563g
5.4. Landslides and Slope Stability
Evidence of landslides, deep-seated landslides, or slope instabilities were not observed at the time of
the field investigation. Additionally, there are no mapped landslides in the vicinity of the project site.
The potential for landslides or slope instabilities to occur at the site is considered very low.
5.5. Liquefaction and Dynamic Settlement
Liquefaction occurs when loose, saturated, generally fine sands and silts are subjected to strong
ground shaking. The soils lose shear strength and become liquid, resulting in large total and differential
ground surface settlements, as well as possible lateral spreading during an earthquake. Due to the
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
11
lack of shallow groundwater and given the relatively dense nature of the materials beneath the site,
the potential for liquefaction and dynamic settlement to occur is considered very low.
5.6. Flooding, Tsunamis, and Seiches
The site is mapped within an area of minimal flood hazard (FEMA, 2019). The site is not located within
a mapped inundation area on the State of California Tsunami Inundation Maps (CGS, 2022); therefore,
damage due to tsunamis is considered negligible. Seiches are periodic oscillations in large bodies of
water such as lakes, harbors, bays, or reservoirs. The site is not located adjacent to any lakes or
confined bodies of water; therefore, the potential for a seiche to affect the site is considered very low.
5.7. Subsidence
The site is not located in an area of known subsidence associated with fluid withdrawal (groundwater
or petroleum); therefore, the potential for subsidence due to the extraction of fluids is considered very
low.
5.8. Hydro-Consolidation
Hydro-consolidation can occur in recently deposited sediments (less than 10,000 years old) that were
deposited in a semi-arid environment. Examples of such sediments are eolian sands, alluvial fan
deposits, and mudflow sediments deposited during flash floods. The pore spaces between the particle
grains can readjust when inundated by groundwater, causing the material to consolidate. The fill and
old paralic deposits underlying the site are not considered susceptible to hydro-consolidation.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
12
6. CONCLUSIONS
Based on the results of NOVA’s investigation, we consider the proposed construction feasible from a
geotechnical standpoint provided the recommendations contained in this report are followed.
Geotechnical conditions exist that should be addressed prior to construction. Geotechnical design and
construction considerations include the following.
There are no known active faults underlying the site. The primary seismic hazard at the site is
the potential for moderate to severe ground shaking in response to large-magnitude
earthquakes generated during the lifetime of the proposed construction. The risk of strong
ground motion is common to all construction in southern California and is typically mitigated
through building design in accordance with the CBC. While strong ground motion could affect
the site, the risk of liquefaction is considered negligible.
The site is underlain by fill and old paralic deposits. The old paralic deposits are considered
suitable for support of structural or fill loads. The fill, however, is potentially compressible and
is not considered suitable for support of structural and fill loads. Recommendations for remedial
grading are provided herein.
The on-site soils tested have a very low expansion potential. These soils are suitable for reuse
as compacted fill. Expansive clays, however, are not considered suitable for direct support of
structures or heave-sensitive improvements. Recommendations for expansive soils are
provided herein.
In general, excavations should be achievable using standard heavy earthmoving equipment in
good working order with experienced operators. However, localized cemented formational
materials and concretions may require extra excavation effort.
The proposed roller coaster building can be supported on spread footings with bottom levels
bearing entirely on aggregate piers or on 3-sack sand/cement slurry that extends down to old
paralic deposits, or it can be supported on cast-in-drilled-hole (CIDH) concrete piles embedded
in old paralic deposits. The proposed airboat ride can be supported on shallow spread footings
or a mat foundation with bottom levels bearing entirely on compacted fill. Site and retaining
walls not connected to buildings can be supported in compacted fill or old paralic deposits.
Recommendations for foundations are provided herein.
Groundwater was not encountered in the borings. However, perched groundwater commonly
occurs where permeable material overlies less permeable materials. Groundwater seepage
may occur in the future due to rainfall, irrigation, broken pipes, or changes in site drainage.
Because groundwater seepage is difficult to predict, such conditions are typically mitigated if
and when they occur.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
13
7. RECOMMENDATIONS
The remainder of this report presents preliminary recommendations regarding earthwork construction
as well as preliminary geotechnical recommendations for the design of the proposed improvements.
These recommendations are based on empirical and analytical methods typical of the standard of
practice in southern California. If these recommendations appear not to address a specific feature of
the project, please contact our office for additions or revisions to the recommendations. The
recommendations presented herein may need to be updated once final plans are developed.
7.1. Earthwork
Grading and earthwork should be conducted in accordance with the CBC and the recommendations
of this report. The following recommendations are provided regarding specific aspects of the proposed
earthwork construction. These recommendations should be considered subject to revision based on
field conditions observed by our offices during grading.
7.1.1 Site Preparation
Site preparation should begin with the removal of existing improvements, vegetation, and debris.
Subsurface improvements that are to be abandoned should be removed, and the resulting excavations
should be backfilled and compacted in accordance with the recommendations of this report. Pipeline
abandonment can consist of capping or rerouting at the project perimeter and removal within the
project perimeter. If appropriate, abandoned pipelines can be filled with grout or slurry as
recommended by and observed by the geotechnical consultant.
7.1.2 Remedial Grading – Rollercoaster Building
Beneath the proposed rollercoaster building pad, the existing soils should be excavated to a depth of
2 feet below planned pad grade elevation. Horizontally, excavations should extend 5 feet outside the
planned perimeter foundations or up to existing improvements or the limits of grading, whichever is
less. NOVA should observe conditions exposed in the bottom of the excavation to determine if
additional excavation is recommended. The resulting surface should then be scarified to a depth of 6
to 8 inches, moisture conditioned to near optimum moisture content, and compacted to at least 90%
relative compaction. The excavation should then be filled to the finished pad grade with compacted fill
having an expansion index (EI) of 50 or less.
7.1.3 Remedial Grading – Airboat Ride
Beneath the proposed airboat ride pad, the existing fill should be excavated in its entirety to expose
competent old paralic deposits. Excavations up to about 4 feet deep are anticipated. Additionally, the
old paralic deposits should be excavated to a depth of at least 3 feet below the proposed finished pad
elevation or 2 feet below the deepest planned foundation bottom, whichever is deeper. Horizontally,
excavations should extend at least 5 feet outside planned perimeter foundations or up to existing
improvements or the limits of grading, whichever is less. NOVA should observe the conditions exposed
in the bottom of excavations to evaluate whether additional excavation is recommended. The resulting
excavation should be filled to finished pad grade with compacted fill having an expansion index (EI)
of 50 or less.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
14
7.1.4 Remedial Grading – Pedestrian Hardscape
Beneath proposed pedestrian hardscape areas, the existing soils should be excavated to a depth of
at least 2 feet below the existing grade or planned subgrade elevation, whichever is deeper.
Horizontally, excavations should extend at least 2 feet outside the planned hardscape or up to existing
improvements or the limits of grading, whichever is less. If competent old paralic deposits are exposed,
excavation need not be performed. NOVA should observe the conditions exposed at the bottom of
excavations to evaluate whether additional excavation is recommended. The excavation should be
filled with compacted fill having an EI of 50 or less.
7.1.5 Remedial Grading – Retaining Walls and Site Walls
Beneath proposed site walls and retaining walls not connected to buildings, the existing soils should
be excavated to a depth of at least 2 feet below the bottom of the footing. Horizontally, the excavations
should extend at least 2 feet outside the planned wall footing, or up to existing improvements or the
limits of grading, whichever is less. If competent old paralic deposits are exposed, excavation need
not be performed. NOVA should observe the conditions exposed at the bottom of excavations to
evaluate whether additional excavation is recommended. Any required fill should have an EI of 50 or
less.
7.1.6 Remedial Grading – Vehicular Pavements
Beneath vehicular pavement areas, existing soils should be excavated to a depth of at least 1 foot
below existing grade or planned subgrade elevation, whichever is deeper. Horizontally, excavations
should extend at least 2 feet outside the planned pavement or up to existing improvements or the
limits of grading, whichever is less. If suitable formational materials are exposed, excavation need not
be performed. NOVA should observe the conditions exposed in the bottom of excavations to evaluate
whether additional excavation is recommended. The excavation should be filled with material suitable
for use as compacted fill.
7.1.7 Expansive Soil
The on-site soils tested have EIs ranging from 0 to 5, classified as very low expansion potential. To
reduce the potential for expansive heave, the top 2 feet of material beneath footings and concrete
slabs should have an EI of 50 or less. Horizontally, the soils having an EI of 50 or less should extend
at least 2 feet outside footings and concrete slabs or up to existing improvements or the limits of
grading, whichever is less. We expect that the on-site silty sand and clayey sand will meet the EI
criterion. Clays, if encountered, are not expected to meet the EI criterion.
7.1.8 Compacted Fill
Excavated soils free of organic matter, construction debris, rocks greater than 6 inches, and expansive
soil as described above should generally be suitable for reuse as compacted fill. Areas to receive fill
should be scarified to a depth of 6 to 8 inches, moisture conditioned to near optimum moisture content,
and compacted to at least 90% relative compaction. If competent old paralic deposits are exposed,
scarification and re-compaction need not be performed. Fill and backfill should be placed in 6- to 8-
inch-thick loose lifts, moisture conditioned to near optimum moisture content, and compacted to at
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
15
least 90% relative compaction. The maximum density and optimum moisture content for the evaluation
of relative compaction should be determined in accordance with ASTM D1557.
7.1.9 Imported Soil
Imported soil should consist of predominately granular soil, free of organic matter and rocks greater
than 6 inches. Imported soil should be observed and, if appropriate, tested by NOVA prior to transport
to the site to evaluate suitability for the intended use.
7.1.10 Subgrade Stabilization
Excavation bottoms should be firm and unyielding prior to placing fill. In areas of saturated or yielding
subgrade, a reinforcing geogrid such as Tensar® InterAxTM NX650 or equivalent can be placed on the
excavation bottom, and then at least 12 inches of aggregate base placed and compacted. Once the
surface of the aggregate base is firm enough to achieve compaction, then the remaining excavation
should be filled to finished pad grade with suitable material.
7.1.11 Excavation Characteristics
It is anticipated that excavations can be achieved with conventional earthwork equipment in good
working order with experienced operators. However, localized cemented formational materials and
concretions may require extra excavation effort. Excavations may generate oversized materials that
will require extra effort to screen or export from the site.
7.1.12 Oversized Material
Excavations may generate oversized material. Oversized material is defined as rocks or cemented
clasts greater than 6 inches in largest dimension. Oversized material should be broken down to no
greater than 6 inches in largest dimension for use in fill, use as landscape material, or disposed of off-
site.
7.1.13 Temporary Excavations
Temporary excavations 3 feet deep or less can be made vertically. Deeper temporary excavations in
fill or old paralic deposits should be laid back no steeper than 1:1 (horizontal:vertical) (h:v). The faces
of temporary slopes should be inspected daily by the contractor’s Competent Person before personnel
are allowed to enter the excavation. Any zones of potential instability, sloughing, or raveling should be
brought to the attention of the engineer and corrective action implemented before personnel begin
working in the excavation. Excavated soils should not be stockpiled behind temporary excavations
within a distance equal to the depth of the excavation. NOVA should be notified if other surcharge
loads are anticipated so that lateral load criteria can be developed for the specific situation. If
temporary slopes are to be maintained during the rainy season, berms are recommended along the
tops of slopes to prevent runoff water from entering the excavation and eroding the slope faces.
Slopes steeper than those described above will require shoring. Additionally, temporary excavations
that extend below a plane inclined at 1½:1 (h:v) downward from the outside bottom edge of existing
structures or improvements will require shoring. Soldier piles and lagging, internally braced shoring,
or trench boxes could be used. If trench boxes are used, the soil immediately adjacent to the trench
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
16
box is not directly supported. Ground surface deformations immediately adjacent to the pit or trench
could be greater where trench boxes are used compared to other methods of shoring.
7.1.14 Groundwater Seepage
Seepage from perched groundwater may occur locally in excavations due to conditions not observed
during our investigation. If dewatering is necessary, the dewatering method should be evaluated and
implemented by an experienced dewatering subcontractor.
7.1.15 Slopes
Permanent slopes should be constructed no steeper than 2:1 (h:v). Faces of fill slopes should be
compacted either by rolling with a sheepsfoot roller or other suitable equipment, or by overfilling and
cutting back to design grade. Fills should be benched into sloping ground inclined steeper than 5:1
(h:v). In our opinion, slopes constructed no steeper than 2:1 (h:v) will possess an adequate factor of
safety. An engineering geologist should observe cut slopes during grading to ascertain that no
unforeseen adverse geologic conditions are encountered that require revised recommendations.
Slopes are susceptible to surficial slope failure and erosion. Water should not be allowed to flow over
the top of slope. Additionally, slopes should be planted with vegetation that will reduce the potential
for erosion.
7.1.16 Surface Drainage
Final surface grades around structures should be designed to collect and direct surface water away
from structures, including retaining walls, and toward appropriate drainage facilities. The ground
around the structure should be graded so that surface water flows rapidly away from the structure
without ponding. In general, we recommend that the ground adjacent to the structure slope away at a
gradient of at least 2%. Densely vegetated areas where runoff can be impaired should have a
minimum gradient of at least 5% within the first 5 feet from the structure. Roof gutters with downspouts
that discharge directly into a closed drainage system are recommended on structures. Drainage
patterns established at the time of fine grading should be maintained throughout the life of the
proposed structures. Site irrigation should be limited to the minimum necessary to sustain landscape
growth. Should excessive irrigation, impaired drainage, or unusually high rainfall occur, saturated
zones of perched groundwater can develop.
7.1.17 Grading Plan Review
NOVA should review the grading plans and earthwork specifications to ascertain whether the intent of
the recommendations contained in this report have been implemented, and that no revised
recommendations are needed due to changes in the development scheme.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
17
7.2. Foundations
The foundation recommendations provided herein are considered generally consistent with methods
typically used in southern California. Other alternatives may be available. Our recommendations are
only minimum criteria based on geotechnical factors and should not be considered a structural design,
or to preclude more restrictive criteria of governing agencies or by the structural engineer. The design
of the foundation system should be performed by the project structural engineer, incorporating the
geotechnical parameters described herein and the requirements of applicable building codes.
Foundations for individual structures should not be underlain by cut/fill transitions. The proposed roller
coaster building should be supported on spread footings with bottom levels bearing on aggregate piers
or 3-sack sand/cement slurry that extends down to old paralic deposits or on CIDH concrete piles
embedded in old paralic deposits. The proposed airboat ride should be supported on shallow spread
footings or a mat foundation with bottom levels bearing entirely on compacted fill. Site and retaining
walls not connected to buildings should be supported in compacted fill or old paralic deposits.
7.2.1 Spread Footings
Footings should extend at least 24 inches below lowest adjacent finished grade. A minimum width of
18 inches is recommended for continuous footings and 24 inches for isolated or retaining wall footings.
An allowable bearing capacity of 3,500 psf can be used for spread footings supported on competent
old paralic deposits or on 3-sack sand/cement slurry or aggregate piers extending down to competent
old paralic deposits. An allowable bearing capacity of 2,500 psf can be used for spread footings
supported on compacted fill. The allowable bearing capacity can be increased by 500 psf for each foot
of depth below the minimum and 250 psf for each foot of width beyond the minimum up to a maximum
of 5,000 psf. The bearing value can be increased by ⅓ when considering the total of all loads, including
wind or seismic forces. Footings located adjacent to or within slopes should be extended to a depth
such that a minimum horizontal distance of 10 feet exists between the lower outside footing edge and
the face of the slope.
Lateral loads will be resisted by friction between the bottoms of footings and passive pressure on the
faces of footings and other structural elements below grade. An allowable coefficient of friction of 0.35
can be used. An allowable passive pressure of 350 psf per foot of depth below the ground surface can
be used for level ground conditions. The allowable passive pressure should be reduced for sloping
ground conditions. The passive pressure can be increased by ⅓ when considering the total of all
loads, including wind or seismic forces. The upper 1 foot of soil should not be relied on for passive
support unless the ground is covered with pavements or slabs.
7.2.2 Mat Foundations
The allowable bearing capacity values provided above are also applicable to mat foundations. Mat
foundations typically experience some deflection due to loads placed on the mat and the reaction of
the soils underlying the mat. A design modulus of subgrade reaction, K, of 250 pounds per cubic inch
(pci) can be used for the subgrade soils in evaluating such deflections. This value is based on an area
of 1 square foot and should be adjusted for larger mats. Adjusted values of the modulus of subgrade
reaction, Kv, can be obtained from the following equation for square mats of various widths:
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
18
𝐾 ൌ𝐾B 1
2B ൨
ଶ
ሺ𝑝𝑐𝑖ሻ
Where B is the width of the mat in feet.
Adjusted values of the modulus of subgrade reaction, K’, can be obtained from the following equation
for rectangular mats:
𝐾ᇱ ൌ
𝐾௩ ቆ1 0.5 ቀ𝐵
𝐿ቁቇ
1.5 ሺ𝑝𝑐𝑖ሻ
Where B is the width and L is the length of the mat in feet.
7.2.3 CIDH Piles
CIDH piles should be spaced at least three pile diameters, center to center, and be embedded in
compacted fill and/or formational materials. The axial downward capacity of piles can be obtained from
skin friction and end bearing. An allowable downward skin friction of 300 psf and an allowable end
bearing of 4,000 psf can be used. If end bearing is used, the bottom of drilled holes should be cleaned
of loose soil prior to placing concrete. The axial uplift capacity of piles can be obtained from skin friction
and the weight of the pile. An allowable uplift skin friction of 100 psf can be used. Lateral loads can be
resisted by passive pressure on the piles. An allowable passive pressure of 350 psf per foot of
embedment acting on twice the pile diameter up to a maximum of 5,000 psf can be used, based on a
lateral deflection up to ½ inch at the ground surface and level ground conditions. The axial and passive
pressure values can be increased by ⅓ when considering the total of all loads, including wind or
seismic forces. The upper 1 foot of soil should not be relied on for passive support unless the ground
is covered with pavements or slabs.
7.2.4 Settlement Characteristics
Total foundation settlements are estimated to be less than ¾ inch. Differential settlements are
estimated to be less than ½ inch between adjacent columns and across continuous footings over a
distance of 40 feet. Settlements should be completed shortly after structural loads are applied.
7.2.5 Foundation Plan Review
NOVA should review the foundation plans to ascertain that the intent of the recommendations in this
report has been implemented and that revised recommendations are not necessary as a result of
changes after this report was completed.
7.2.6 Foundation Excavation Observations
A representative from NOVA should observe the foundation excavations prior to forming or placing
reinforcing steel.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
19
7.3. Pedestrian Hardscape
Pedestrian hardscape should be underlain by at least 2 feet of material with an EI of 50 or less. The
top 12 inches of subgrade soils should be scarified, moisture conditioned to near optimum moisture
content, and compacted to at least 90% relative compaction. If suitable formational materials are
exposed, scarification and re-compaction need not be performed. Subgrade preparation should be
performed immediately prior to placement of the hardscape.
Exterior slabs should be at least 4 inches in thickness and reinforced with at least No. 3 bars at 18
inches on center each way. Slabs should be provided with weakened plane joints. Joints should be
placed in accordance with the American Concrete Institute (ACI) guidelines. The project architect
should select the final joint patterns. A 1-inch maximum size aggregate mix is recommended for
concrete for exterior slabs. The corrosion potential of on-site soils with respect to reinforced concrete
will need to be taken into account in concrete mix design. Coarse and fine aggregate in concrete
should conform to the “Greenbook” Standard Specifications for Public Works Construction.
7.4. Conventional Retaining Walls and Site Walls
Conventional retaining walls can be supported on spread footings. The recommendations for spread
footings provided in the foundation section of this report are also applicable to conventional retaining
walls.
The active earth pressure for the design of unrestrained retaining walls with level backfill can be taken
as equivalent to the pressure of a fluid weighing 40 pounds per cubic foot (pcf). The at-rest earth
pressure for the design of restrained retaining wall with level backfill can be taken as equivalent to the
pressure of a fluid weighing 60 pcf. These values assume a granular and drained backfill condition.
Higher lateral earth pressures would apply if walls retain clay soils. An additional 20 pcf should be
added to these values for walls with 2:1 (h:v) sloping backfill. An increase in earth pressure equivalent
to an additional 2 feet of retained soil can be used to account for surcharge loads from light traffic. The
above values do not include a factor of safety. Appropriate factors of safety should be incorporated
into the design. If any other surcharge loads are anticipated, NOVA should be contacted for the
necessary increase in soil pressure.
The seismic earth pressure can be taken as equivalent to the pressure of a fluid pressure weighing
14 pcf. This value is for level backfill and does not include a factor of safety. Appropriate factors of
safety should be incorporated into the design. This pressure is in addition to the un-factored, active
earth pressure. The total equivalent fluid pressure can be modeled as a triangular pressure distribution
with the resultant acting at a height of H/3 up from the base of the wall, where H is the retained height
of the wall. The passive pressure and bearing capacity can be increased by ⅓ in determining the
seismic stability of the wall.
Retaining walls should be provided with a backdrain to reduce the accumulation of hydrostatic
pressures or be designed to resist hydrostatic pressures. Backdrains can consist of a 2-foot-wide zone
of ¾-inch crushed rock. The crushed rock should be separated from the adjacent soils using a non-
woven filter fabric, such as Mirafi 140N or equivalent. A perforated pipe should be installed at the base
of the backdrain and sloped to discharge to a suitable storm drain facility, or weep holes should be
provided. As an alternative, a geocomposite drainage system such as Miradrain 6000 or equivalent
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
20
placed behind the wall and connected to a suitable storm drain facility can be used. The project
architect should provide dampproofing/waterproofing specifications and details. Figure 7-1 presents a
typical conventional retaining wall backdrain detail. Note that the guidance provided on Figure 7-1 is
conceptual. Other options are available.
Wall backfill should consist of granular, free-draining material having an EI of 20 or less. The backfill
zone is defined by a 1:1 plane projected upward from the heel of the wall. Expansive or clayey soil
should not be used. Additionally, backfill within 3 feet from the back of the wall should not contain
rocks greater than 3 inches in dimension. Backfill should be compacted to at least 90% relative
compaction. Backfill should not be placed until walls have achieved adequate structural strength.
Compaction of wall backfill will be necessary to minimize settlement of the backfill and overlying
settlement-sensitive improvements. However, some settlement should still be anticipated. Provisions
should be made for some settlement of concrete slabs and pavements supported on backfill.
Additionally, any utilities supported on backfill should be designed to tolerate differential settlement.
Figure 7-1. Typical Conventional Retaining Wall Backdrain Detail
RETAINING
WALL
FINISHED
GRADE
CONCRETE
BROWDITCH
FOOTING
12"
GROUND SURFACE
WATER PROOFING
PER ARCHITECT
FILTER FABRIC ENVELOPE
(MIRAFI 140N OR APPROVED
EQUIVALENT)
3/4" CRUSHED ROCK
(1 CU .FT./FT.)
FILTER FABRIC
ENVELOPE
MIRAFI 140N OR
EQU IVALENT
4" DIA. SCHEDULE 40
PERFORATED PVC PIPE
OR TOTAL DRAIN
/\'--,~/>/~ EXTENDED TO
APPROVED OUTLET
COMPETENT BEDROCK
OR MATERIAL AS
EVALUATED BY THE
GEOTECHNICAL
CONSULTANT
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
21
7.5. Pavement Section Recommendations
Based on the results of our laboratory testing, an R-value of 16 was assumed for design of preliminary
pavement sections. The actual R-value of the subgrade soils should be determined after grading, and
the final pavement sections provided. Based on an R-value of 16, the following preliminary pavement
structural sections are provided for the assumed Traffic Indexes on Table 7-1.
Table 7-1. AC and PCC Pavement Sections
Traffic Type Traffic Index Asphalt Concrete
(inches)
Portland Cement Concrete
(inches)
Parking Stalls 4.5 3 AC / 7 AB 6½ PCC / 4 AB
Driveways 6.0 4 AC / 10 AB 7 PCC / 4 AB
Fire Lanes 7.5 5 AC / 14 AB 7½ PCC / 4 AB
AC: Asphalt Concrete
AB: Aggregate Base
PCC: Portland Cement Concrete
Subgrade preparation should be performed immediately prior to placement of the pavement section.
The top 12 inches of subgrade should be scarified, moisture conditioned to near optimum moisture
content, and compacted to at least 95% relative compaction. All soft or yielding areas should be
stabilized or removed and replaced with compacted fill or aggregate base. Aggregate base and asphalt
concrete should conform to the Caltrans Standard Specifications or the “Greenbook” and should be
compacted to at least 95% relative compaction. Aggregate base should have an R-value of not less
than 78. All materials and methods of construction should conform to good engineering practices and
the minimum local standards.
7.6. Pipelines
For level ground conditions, a passive earth pressure of 350 psf per foot of depth below the lowest
adjacent final grade can be used to compute allowable thrust block resistance. A value of 150 psf per
foot should be used below groundwater level, if encountered.
A modulus of soil reaction (E’) of 1,500 psi can be used to evaluate the deflection of buried flexible
pipelines. This value assumes that granular bedding material is placed adjacent to the pipe and is
compacted to at least 90% relative compaction.
Pipe bedding as specified in the “Greenbook” Standard Specifications for Public Works Construction
can be used. Bedding material should consist of clean sand having a sand equivalent not less than
20 and should extend to at least 12 inches above the top of pipe. Alternative materials meeting the
intent of the bedding specifications are also acceptable. Samples of materials proposed for use as
bedding should be provided to the engineer for inspection and testing before the material is imported
for use on the project. The on-site materials are not expected to meet “Greenbook” bedding
specifications. The pipe bedding material should be placed over the full width of the trench. After
placement of the pipe, the bedding should be brought up uniformly on both sides of the pipe to reduce
the potential for unbalanced loads. No voids or uncompacted areas should be left beneath the pipe
haunches. Ponding or jetting the pipe bedding should not be allowed.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
22
Where pipeline inclinations exceed 15%, cutoff walls are recommended in trench excavations. Open
graded rock should not be used for pipe bedding or backfill due to the potential for piping erosion. The
recommended bedding is clean sand having a sand equivalent not less than 20 or 2-sack sand/cement
slurry. If sand/cement slurry is used for pipe bedding to at least 1 foot over the top of the pipe, cutoff
walls are not considered necessary. The need for cutoff walls should be further evaluated by the
project civil engineer designing the pipeline.
7.7. Corrosivity
Representative samples of the on-site soils were tested to evaluate corrosion potential. The test
results are presented in Appendix C. The project design engineer can use the sulfate results in
conjunction with ACI 318 to specify the water/cement ratio, compressive strength, and cementitious
material types for concrete exposed to soil. The project design engineer should review and consider
the resistivity levels in the project design. A corrosion engineer should be contacted to provide specific
corrosion control recommendations.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
23
8. CLOSURE
NOVA should review project plans and specifications prior to bidding and construction to check that
the intent of the recommendations in this report has been incorporated. Observations and tests should
be performed during construction. If the conditions encountered during construction differ from those
anticipated based on the subsurface exploration program, the presence of personnel from our offices
during construction will enable an evaluation of the exposed conditions and modifications of the
recommendations in this report or development of additional recommendations in a timely manner.
NOVA should be advised of changes in the project scope so that the recommendations contained in
this report can be evaluated with respect to the revised plans. Changes in recommendations will be
verified in writing. The findings in this report are valid as of the date of this report. Changes in the
condition of the site can, however, occur with the passage of time, whether they are due to natural
processes or work on this or adjacent areas. In addition, changes in the standards of practice and
government regulations can occur. Thus, the findings in this report may be invalidated wholly or in part
by changes beyond our control. This report should not be relied upon after a period of two years
without a review by us verifying the suitability of the conclusions and recommendations to site
conditions at that time.
In the performance of our professional services, we comply with that level of care and skill ordinarily
exercised by members of our profession currently practicing under similar conditions and in the same
locality. The client recognizes that subsurface conditions may vary from those encountered at the
boring locations and that our data, interpretations, and recommendations are based solely on the
information obtained by us. We will be responsible for those data, interpretations, and
recommendations, but shall not be responsible for interpretations by others of the information
developed. Our services consist of professional consultation and observation only, and no warranty
whatsoever, express or implied, is made or intended in connection with the work performed or to be
performed by us, or by our proposal for consulting or other services, or by our furnishing of oral or
written reports or findings.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
24
9. REFERENCES
American Concrete Institute, 2014, Building Code Requirements for Structural Concrete (ACI 318-14)
and Commentary, dated September.
American Society of Civil Engineers (ASCE), 2023, ASCE 7 Hazard Tool: found at
https://asce7hazardtool.online/, accessed August 2023.
California Department of Transportation (Caltrans) 2018, Standard Specifications.
California Geological Survey (CGS), 2002, California Geomorphic Provinces Note 36, Electronic
Copy, Revised December 2002.
, 2008, Guidelines for Evaluating and Mitigating Seismic Hazards in California, Special
Publication 117A, September 2008.
, 2010, Fault Activity Map of California, California Geologic Data Map Series, Map No. 6.
, 2011, Susceptibility to Deep-Seated Landslides in California.
, 2018, Earthquake Fault Zones, Special Publication 42, Revised 2018.
, 2022, Tsunami Hazard Area Map, County of San Diego; Produced by the California
Governor’s Office of Emergency Services; dated October 7, mapped at 1:72,000 scale.
California State Water Resources Control Board, GeoTracker website:
https://geotracker.waterboards.ca.gov/, accessed July 2023.
Commercial Development Resources (CDR), 2023, Combined Topographic Survey, Legoland, Driving
School, Carlsbad, CA 92008, Topo-22156.dwg, dated February 16.
Federal Emergency Management Agency, 2019, FIRM Flood Insurance Rate Map, City of Carlsbad,
Firm Panels 06073C0764H, https://msc.fema.gov/portal/search, effective December 20; accessed
July 2023.
Google Earth Pro, found at: http://www.google.com/earth/index.html, accessed July 2023.
Historic Aerials Website, https://www.historicaerials.com/, accessed July 2023.
International Code Council, 2021, 2022 California Building Code, California Code of Regulations, Title
24, Part 2, Volume 2 of 2, Based on the 2021 International Building Code, Effective 1/1/23.
Kennedy, M.P. and Tan, S.S., 2007, Geologic Map of the Oceanside 30’ x 60’ Quadrangle, California,
California Geological Survey, Scale 1:100,000.
NOVA, 2021, Geotechnical Investigation, SDP 2021-0020 LEGOLAND Project 2023, One Legoland
Drive, Carlsbad, CA, Project No. 2021170, November 22.
Public Works Standards, Inc., 2018, “Greenbook” Standard Specifications for Public Works
Construction, 2018 Edition.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
25
R.W. Apel Landscape Architects Inc. (RWA), 2023, Area Development Illustrative Plan, 50%
Construction Documents, Project 2025, One Legoland Drive, Carlsbad, California 92008 USA, Project
No. 4139.00, Sheet L-101, dated April 28.
Tan, S.S., 1995, Landslide Hazards in San Diego County, California, California Division of Mines and
Geology.
United States Geological Survey (USGS), USGS Geologic Hazards Science Center, U.S. Quaternary
Faults, accessed July 2023.
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
PLATES
EX.SITELIGHT
EX. BUILDING TO REMAIN(+-166.30FF)
(164.65FS)
STEPS
(162.84FS)MIGHT BE
REMOVED SAFETY SURFACE
2% MAX
162.77FS (162.71FS)
(165.10FS)
(162.99FS)
(165.10FS)
162.88
FS
162.71FS
EX. RAMP
TO REMAIN
162.50TG(163.20FS)
(164.52TW)
162.10FS-BW(163.20EG)
164.57TW
162.60FS-BW(163.15EG)
167.00TW
162.55FS-BW
EX. SDCB
TO REMAIN
162.00
PROP.
SDMH RIM
(161.54TC)
(161.52FS)
7.2%
(161.52TC)
(161.02FS)
2.0%
1.5%
166.75TW
162.20FS-BW
162.55FS
162.75DOOR
162.75DOOR
162.30TG
162.75
DOOR
2.0%
162.33
TG
162.75DOOR
162.75FFE
162.33PAD
161.95TG 162.75
DOOR
162.20FL-HP
162.75
DOOR
162.00TG
161.88TG 162.30TG
162.75FFE
162.33PAD(5" CONC SLAB)
162.30TG
1.1%
(161.21FS)
EX. PRIVATE 24" STORM
DRAIN TO REMAIN(PENDING
CAMERA/INSPECTION/CITYAPPROVAL)
ADJUST
EX. SDMH TO GRADE OF
SLAB/GRAVEL
156.92RIM(162.53RIM)
(161.54TC)
(161.04FS)
161.95TG
2.0%
162.25FS
161.86TG
161.80TS(4) 6-3/4"
RISERS
159.55
FS-BS
2.0%162.25
FS
162.50TC
162.09TG
162.00FG
162.62TW162.29FS
161.00FG-BW
162.87TW
162.54FS
161.00FG-BW
162.75
DOOR
162.25FS 162.25FS 162.25FS
1621611.0%160158.80TG 159
160
164
165166
164 163 163
164
162
160 160 160
161 162 162163
161
EX LANDSCAPING
(N.A.P.)
EX LANDSCAPING(N.A.P.)
163
162
161.47FL-HP
(158.05.FS)1.0%161 1621.0%
162.75
DOOR
1.0%
162.75FFE
162.33PAD(5" CONC SLAB)
162.75
DOOR
162.75
DOOR
161.07TG
(158.85FS)
161.95-TG
LOW
POINT
2.0%
161.57
FG-HP
161.95TG
2.0%162.50FS
156.92FFE156.42PAD
(6" GRAVEL)
2.0%
(160.15FS)
162.75
DOOR
162.70
FS162.62
FS 162.90FFE
162.62
FS-HP
165.50TW
162.62FS-BW(163.53EG)
2.0%
1.2%
(164.91FS)(164.52TW)
162.10FS-BW(163.10EG)
162.34FS 162.62FS
(164.52TW)
162.70FS-BW(163.20EG)
162.62FS
162.62FS 1.2%
164.36TW
162.67FS-BW(163.17BW)
1.5%
163.00
DOOR
162.76FS
162.50FS
162.21TG
161.90TG163.00
DOOR
163.00FFE
162.58PAD(5" CONC SLAB)162.75
DOOR 162.75
DOOR
(162.53FS)
MATCH
162.82TC
(162.49FS)
162.00TG
162.64FS
162.48
FS162.44RIM
162.18TG
162.33FS
162.25TG
(162.57FS)
MATCH
(162.57FS)
MATCH
(162.70FS)
162.66FS
162.56FS
162.98FS
162.55FS 162.40TG 162.48FS
(164.40FS)
(164.20FS)
162.54FS
1.4%
1.0
%
162
2:1 MA
X
2.0
%
2.0
%
2.0
%
2:1 MA
X 2:1
2.0
%
MA
X
2.0
%
2.0
%
161
1.
5
%
2.0
%2.
0
%
16
2
16
2
162
161
1.0%
162
159
2.0%
1.8
%
161
162
2.0%
16
1
161
163
162
1.5%
162
162
16
1
16
0
164
16
3
1.
0
%
16
0
1.5%
2.0%
2.
0
%
1.0%
1.5%
162 161
1.0%
1.0%
1.8
%
1.8
%
2.0
%
1.0
%
1.0%
1.0%
1.
0
%
1.
0
%
16
2
162
16
2
1.9
%
B-1
af
Qop
B-5
B-3
B-4
A
A'
B-2
4373 Viewridge Avenue, Suite B
San Diego, CA 92123
P: 858.292.7575
944 Calle Amanecer, Suite F
San Clemente, CA 92673
P: 949.388.7710
NOVA
LE
G
O
L
A
N
D
C
A
L
I
F
O
R
N
I
A
P
R
O
J
E
C
T
2
0
2
5
ON
E
L
E
G
O
L
A
N
D
D
R
I
V
E
CA
R
L
S
B
A
D
,
C
A
9
2
0
0
8
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
DVBE
www.usa-nova.com
PROJECT NO.:
DATE:
DRAWN BY:
REVIEWED BY:
2022239
AUG 2023
DTJ
GD
GEOTECHNICAL MAP
DRAWING TITLE:
SCALE:1"=40'
PLATE NO.1 OF 2
SBE SDVOSB SLBE
0 40'80'
NW E
N
S
*BASE MAP: CDR, 2023
*NOTE: ALL LOCATIONS APPROXIMATE
KEY TO SYMBOLS
af FILL
Qop OLD PARALIC DEPOSITS
GEOTECHNICAL BORING
(NOVA, 2023)
B-5
GEOLOGIC CROSS-SECTIONAA'
GEOLOGIC CONTACT,
QUERIED WHERE UNCERTAIN?
LIMITS OF REMEDIAL GRADING
GEOTECHNICAL BORING
(NOVA, 2021)
B-2
I
"'
' I
7
I ....
~ ,;½
J
V) .. • ..
' { .q,
r-; . ., • /. ,• ____,,,-• J ..
•
L.....J
i
160
200
A
0 40 80 120 160 200 240 280 320120
El
e
v
a
t
i
o
n
,
f
e
e
t
(
N
G
V
D
2
9
)
360 400
TD=21½'
TD=11½'
B-4
TD=28½'TD=31½'
B-1(PROJECTED
32' NORTH)B-2
PROPOSED ROLLERCOASTER BUILDING
QopQop
af
af 160
200
A'
120
El
e
v
a
t
i
o
n
,
f
e
e
t
(
N
G
V
D
2
9
)
PROPOSED AIRBOAT RIDE
????????
(PROJECTED
6' SOUTH)B-5(PROJECTED
69' NORTH)FSE=162.3
FFE=156.92
EXISTING GRADE
4373 Viewridge Avenue, Suite B
San Diego, CA 92123
P: 858.292.7575
944 Calle Amanecer, Suite F
San Clemente, CA 92673
P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
DVBE
www.usa-nova.com
GEOLOGIC
CROSS-SECTION
PLATE NO.2 OF 2
SBE SDVOSB SLBE
KEY TO SYMBOLS
af FILL
0 40'80'
*NOTE: ALL LOCATIONS APPROXIMATE
Qop OLD PARALIC DEPOSITS
GEOTECHNICAL BORING
(NOVA, 2023)
GEOLOGIC CONTACT,
QUERIED WHERE UNCERTAIN?
B-5
GEOTECHNICAL BORING
(NOVA, 2021)
B-2
LE
G
O
L
A
N
D
C
A
L
I
F
O
R
N
I
A
P
R
O
J
E
C
T
2
0
2
5
ON
E
L
E
G
O
L
A
N
D
D
R
I
V
E
CA
R
L
S
B
A
D
,
C
A
9
2
0
0
8
PROJECT NO.:
DATE:
DRAWN BY:
REVIEWED BY:
2022239
AUG 2023
DTJ
GD
DRAWING TITLE:
SCALE:1"=40'
FFE=FINISH FLOOR ELEVATION
FSE=FINISHED SURFACE ELEVATION
,a~ , __
. . .
,__ -
~ -
r ,__ =
1----1---'--
-
--------------L-----
L---
---'---
I I I I I I I I I I I I I I I I I I I
1
1
- -
L
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
APPENDIX A
USE OF THE GEOTECHNICAL REPORT
Im ortant Information About Your
Geotechnical Engineering Report
Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.
The following information is provided to help you manage your risks.
Geotechnical Services Are Performed for
Specific Purposes, Persons, and Projects
Geotechnical engineers structure their services to meet the specific needs of
their clients. A geotechnical engineering study conducted for a civil engi-
neer may not fulfill the needs of a construction contractor or even another
civil engineer. Because each geotechnical engineering study is unique, each
geotechnical engineering report is unique, prepared solelyfor the client. No
one except you should rely on your geotechnical engineering report without
first conferring with the geotechnical engineer who prepared it. And no one
-not even you -should apply the report for any purpose or project
except the one originally contemplated.
Read the Full Report
Serious problems have occurred because those relying on a geotechnical
engineering report did not read it all. Do not rely on an executive summary.
Do not read selected elements only.
A Geotechnical Engineering R~port Is Based on
A Unique Set of Project-Specific Factors
Geotechnical engineers consider a number of unique, project-specific fac-
tors when establishing the scope of a study. Typical factors include: the
client's goals, objectives, and risk management preferences: the general
nature of the structure involved, its size, and configuration: the location of
the structure on the site: and other planned or existing site improvements,
such as access roads, parking lots, and underground utilities. Unless the
geotechnical engineer who conducted the study specifically indicates oth-
erwise, do not rely on a geotechnical engineering report that was:
• not prepared for you,
• not prepared for your project.
• not prepared for the specific site explored, or
• completed before important project changes were made.
Typical changes that can erode the reliability of an existing geotechnical
engineering report include those that affect:
• the function of the proposed structure, as when it's changed from a
parking garage to an office building , or from a light industrial plant
to a refrigerated warehouse,
• elevation, configuration, location, orientation, or weight of the
proposed structure,
• composition of the design team, or
• project ownership.
As a general rule, always inform your geotechnical engineer of project
changes-even minor ones-and request an assessment of their impact.
Geotechnical engineers cannot accept responsibility or liability for problems
that occur because their reports do not consider developments of which
they were not informed
Subsurface Conditions Can Change
A geotechnical engineering report is based on conditions that existed at
the time the study was performed. Do not rely on a geotechnical engineer-
ing reportwhose adequacy may have been affected by: the passage of
time; by man-made events, such as construction on or adjacent to the site;
or by natural events, such as floods, earthquakes, or groundwater fluctua-
tions. Always contact the geotechnical engineer before applying the report
to determine if it is still reliable. A minor amount of additional testing or
analysis could prevent major problems.
Most Geotechnical Findings Are Professional
Opinions
Site exploration identifies subsurface conditions only at those points where
subsurface tests are conducted or samples are taken. Geotechnical engi-
neers review field and laboratory data and then apply their professional
judgment to render an opinion about subsurface conditions throughout the
site. Actual subsurface conditions may differ-sometimes significantly-
from those indicated in your report. Retaining the geotechnical engineer
who developed your report to provide construction observation is the
most effective method of managing the risks associated with unanticipated
conditions.
A Report's Recommendations Are Not Final
Do not overrely on the construction recommendations included in your
report. Those recommendations are not final, because geotechnical engi-
neers develop them principally from judgment and opinion. Geotechnical
engineers can finalize their recommendations only by observing actual
subsurface conditions revealed during construction. The geotechnical
engineer who developed your report cannot assume responsibility or
liability for the report's recommendations if that engineer does not perform
construction observation.
A Geotechnical Engineering Report Is Subject to
Misinterpretation
Other design team members' misinterpretation of geotechnical engineering
reports has resulted in costly problems. Lower that risk by having your geo-
technical engineer confer with appropriate members of the design team after
submitting the report. Also retain your geotechnical engineer to review perti-
nent elements of the design team's plans and specifications. Contractors can
also misinterpret a geotechnical engineering report. Reduce that risk by
having your geotechnical engineer participate in prebid and preconstruction
conferences, and by providing construction observation.
Do Not Redraw the Engineer's Logs
Geotechnical engineers prepare final boring and testing logs based upon
their interpretation of field logs and laboratory data. To prevent errors or
omissions, the logs included in a geotechnical engineering report should
never be redrawn for inclusion in architectural or other design drawings.
Only photographic or electronic reproduction is acceptable, but recognize
that separating logs from the report can elevate risk.
Give Contractors a Complete Report and
Guidance
Some owners and design professionals mistakenly believe they can make
contractors liable for unanticipated subsurface conditions by limiting what
they provide for bid preparation. To help prevent costly problems, give con-
tractors the complete geotechnical engineering report, but preface it with a
clearly written letter of transmittal. In that letter, advise contractors that the
report was not prepared for purposes of bid development and that the
report's accuracy is limited; encourage them to confer with the geotechnical
engineer who prepared the report (a modest fee may be required) and/or to
conduct additional study to obtain the specific types of information they
need or prefer. A prebid conference can also be valuable. Be sure contrac-
tors have sufficient time to perform additional study. Only then might you
be in a position to give contractors the best information available to you,
while requiring them to at least share some of the financial responsibilities
stemming from unanticipated conditions.
Read Responsibility Provisions Closely
Some clients, design professionals, and contractors do not recognize that
geotechnical engineering is far less exact than other engineering disci-
plines. This lack of understanding has created unrealistic expectations that
have led to disappointments, claims, and disputes. To help reduce the risk
of such outcomes, geotechnical engineers commonly include a variety of
explanatory provisions in their reports. Sometimes labeled "limitations"
many of these provisions indicate where geotechnical engineers' responsi-
bilities begin and end, to help others recognize their own responsibilities
and risks. Read these provisions closely Ask questions. Your geotechnical
engineer should respond fully and frankly.
Geoenvironmental Concerns Are Not Covered
The equipment. techniques, and personnel used to perform a geoenviron-
mental study differ significantly from those used to perform a geotechnical
study. For that reason, a geotechnical engineering report does not usually
relate any geoenvironmental findings, conclusions, or recommendations;
e.g., about the likelihood of encountering underground storage tanks or
regulated contaminants. Unanticipated environmental problems have led
to numerous project failures. If you have not yet obtained your own geoen-
vironmental information, ask your geotechnical consultant for risk man-
agement guidance. Do not rely on an environmental report prepared for
someone else.
Obtain Professional Assistance To Deal with Mold
Diverse strategies can be applied during building design, construction,
operation, and maintenance to prevent significant amounts of mold from
growing on indoor surfaces. To be effective, all such strategies should be
devised for the express purpose of mold prevention, integrated into a com-
prehensive plan, and executed with diligent oversight by a professional
mold prevention consultant. Because just a small amount of water or
moisture can lead to the development of severe mold infestations, a num-
ber of mold prevention strategies focus on keeping building surfaces dry.
While groundwater, water infiltration, and similar issues may have been
addressed as part of the geotechnical engineering study whose findings
are conveyed in this report, the geotechnical engineer in charge of this
project is not a mold prevention consultant; none of the services per-
formed in connection with the geotechnical engineer's study
were designed or conducted for the purpose of mold preven-
tion. Proper implementation of the recommendations conveyed
in this report will not of itself be sufficient to prevent mold
from growing in or on the structure involved.
Rely, on Your ASFE-Member Geotechncial
Engineer for Additional Assistance
Membership in ASFE/The Best People on Earth exposes geotechnical
engineers to a wide array of risk management techniques that can be of
genuine benefit for everyone involved with a construction project. Confer
with you ASFE-member geotechnical engineer for more information.
ASFE
The Best People 10 larlh
8811 Colesville Road/Suite G106, Silver Spring, MD 20910
Telephone: 301/565-2733 Facsimile: 301/589-2017
e-mail: info@asfe.org www.asfe.org
Copyright 2004 by ASFE, Inc. Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with ASFE'S
specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of ASFE, and only for
purposes of scholarly research or book review. Only members of ASFE may use this document as a complement to or as an element of a geotechnical engineering report. Any other
firm, individual, or other entity that so uses this document without being an ASFE member could be commiling negligent or intentional (fraudulent) misrepresentation.
IIGER06045.0M
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
APPENDIX B
BORING LOGS
SUBSURFACE EXPLORATION LEGEND
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
SBEDVBE SDVOSB
4373 Viewridge Ave., Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
MAJOR DIVISIONS TYPICAL NAMES
GRAVEL
MORE THAN HALF
COARSE FRACTION
IS LARGER THAN
NO. 4 SIEVE GRAVEL WITH
15% OR MORE
FINES
CLEAN GRAVEL
WITH LESS THAN
15% FINES
CLEAN SAND
SAND
MORE THAN HALF
COARSE FRACTION
IS FINER THAN NO.
4 SIEVE SIZE
SAND WITH 15%
OR MORE FINES
WITH LESS THAN
15% FINES
SILTS AND CLAYS
LIQUID LIMIT 50% OR LESS
SILTS AND CLAYS
LIQUID LIMIT GREATER THAN 50%
HIGHLY ORGANIC SOILS
GW
GP
GM
GC
SW
SP
SM
SC
ML
CL
OL
MH
CH
OH
PT
WELL-GRADED GRAVEL WITH OR WITHOUT
SAND
POORLY GRADED GRAVEL WITH OR
WITHOUT SAND
SILTY GRAVEL WITH OR WITHOUT SAND
CLAYEY GRAVEL WITH OR WITHOUT SAND
WELL-GRADED SAND WITH OR WITHOUT
GRAVEL
POORLY GRADED SAND WITH OR WITHOUT
GRAVEL
SILTY SAND WITH OR WITHOUT GRAVEL
CLAYEY SAND WITH OR WITHOUT GRAVEL
SILT WITH OR WITHOUT SAND OR
GRAVEL
ELASTIC SILT WITH OR WITHOUT SAND OR
GRAVEL
FAT CLAY WITH OR WITHOUT SAND OR
GRAVEL
ORGANIC SILT OR CLAY OF HIGH
PLASTICITY WITH OR WITHOUT SAND OR
GRAVEL
PEAT AND OTHER HIGHLY ORGANIC SOILS
FI
N
E
-
G
R
A
I
N
E
D
S
O
I
L
S
CO
A
R
S
E
-
G
R
A
I
N
E
D
S
O
I
L
S
MO
R
E
T
H
A
N
H
A
L
F
I
S
F
I
N
E
R
T
H
A
N
N
O
.
2
0
0
S
I
E
V
E
MO
R
E
T
H
A
N
H
A
L
F
I
S
C
O
A
R
S
E
R
T
H
A
N
N
O
.
2
0
0
S
I
E
V
E
LEAN CLAY WITH OR WITHOUT SAND OR
GRAVEL
ORGANIC SILT OR CLAY OF LOW TO
MEDIUM PLASTICITY WITH OR WITHOUT
SAND OR GRAVEL
RELATIVE DENSITY OF
COHESIONLESS SOILS
RELATIVE DENSITY
VERY LOOSE
LOOSE
MEDIUM DENSE
DENSE
VERY DENSE
SPT N60
BLOWS/FOOT
0 - 4
5 - 10
11 - 30
31 - 50
OVER 50
CONSISTENCY OF COHESIVE SOILS
CONSISTENCY
VERY SOFT
SOFT
MEDIUM STIFF
STIFF
VERY STIFF
HARD
SPT N60
BLOWS/FOOT
0 - 2
3 - 4
5 - 8
9 - 15
16 - 30
OVER 30
NUMBER OF BLOWS OF 140 LB HAMMER FALLING 30 INCHES TO DRIVE A 2 INCH O.D.
(1-3/8 INCH I.D.) SPLIT-BARREL SAMPLER THE LAST 12 INCHES OF AN 18-INCH DRIVE
(ASTM-1586 STANDARD PENETRATION TEST).
IF THE SEATING INTERVAL (1st 6 INCH INTERVAL) IS NOT ACHIEVED, N IS REPORTED AS REF. IF
MORE THAN 50 BLOWS ARE RECORDED IN ANY 6-INCH INTERVAL, N60 IS REPORTED AS REF.
POCKET PENETROMETER
MEASUREMENT (TSF)
0 - 0.25
0.26 - 0.50
0.51 - 1.0
1.1 - 2.0
2.1 - 4.0
OVER 4.0
DIRECT SHEAR
EXPANSION INDEX
ATTERBERG LIMITS
SIEVE ANALYSIS
RESISTANCE VALUE
CONSOLIDATION
SAND EQUIVALENT
CORROSIVITY
MAXIMUM DENSITYMD
DS
EI
AL
SA
RV
CN
SE
LAB TEST ABBREVIATIONS
CR
REFUSALREF
LOG ABBREVIATIONS
BULK SAMPLE
SPT SAMPLE (ASTM D1586)
MOD. CAL. SAMPLE (ASTM D3550)
UNRELIABLE BLOW COUNTS
GEOLOGIC CONTACT
SOIL TYPE CHANGE
*
GROUNDWATER / STABILIZED
GROUNDWATER SEEPAGE
2 /Y
~
181
IZI
□
-
I I
a I ..
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
5
10
15
20
25
30
0
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
FILL (af): CLAYEY SAND; BROWN WITH ORANGE STAINING, MOIST, MEDIUM DENSE, FINE TO
MEDIUM GRAINED, SCATTERED ROOTLETS
SC
29
37
SILTY SAND; DARK BROWN, MOIST, DENSE, FINE TO MEDIUM GRAINED, SCATTERED WHITE
MINERALIZATION
CLAYEY SAND; DARK BROWN WITH GRAY MOTTLING, MOIST, DENSE, FINE TO MEDIUM
GRAINED, SCATTERED GRAVEL
SC
SILTY SAND; BROWN, MOIST, MEDIUM DENSE, FINE TO MEDIUM GRAINEDSM
BORING TERMINATED AT 28½ FT DUE TO AUGER REFUSAL ON VERY DENSE OLD PARALIC
DEPOSITS. NO GROUNDWATER ENCOUNTERED.
SILTY SAND; ORANGE BROWN, MOIST, VERY DENSE, FINE GRAINED, MODERATELY
CEMENTED
SC
35
29
35
REF
81
TRACE ROOTLETS
SM
ORANGE BROWN
CLAYEY SAND; ORANGE BROWN, MOIST, DENSE, FINE TO MEDIUM GRAINED
SM
OLD PARALIC DEPOSITS (Qop): SILTY SAND; BROWN, MOIST, MEDIUM DENSE, FINE TO
MEDIUM GRAINED, POORLY CEMENTED
SM
EI
SA
AL
RV
CR
613
17
12
13
12
13
19
18
10
9
11
8
1113
4150/5"
21
25
30
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
APPENDIX: B.1
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
PROJECT: 2022239DRAFTED BY: AR
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~88.3%, N60 ~ 88.360*N~1.47*N
LOGGED BY:
LOG OF BORING B-1
AUG 13, 2021
± 162 NGVD 29
N/A
FRASTE PL-G HAMMER: 140 LBS., DROP: 30 IN (AUTO)
6-INCH HOLLOW STEM AUGER AR
MS/GD
J -
-➔-+-•-----------------------------------------------------~--/ -
-~-+-•-----------------------------------------------------~--
J_
' / -----------------------------------------------------~---
-----------------------------------------------------~--
z
7
5
10
15
20
25
30
0 FILL (af): CLAYEY SAND; DARK BROWN, MOIST, MEDIUM DENSE, FINE TO MEDIUM GRAINED,
SCATTERED ROOTLETS
SC
22
54
DARK BROWN WITH GRAY MOTTLING, VERY DENSE
DARK BROWN WITH LIGHT AND DARK GRAY MOTTLING, MEDIUM DENSE, TRACE GRAVEL
ORANGE BROWN, VERY DENSE, FINE GRAINED, MODERATELY CEMENTED
25
25
32
51
ORANGE BROWN
DARK ORANGE BROWN, DENSE
BROWN
LIGHT GRAY
OLD PARALIC DEPOSITS (Qop): SILTY SAND; ORANGE BROWN, MOIST, MEDIUM DENSE,
FINE TO MEDIUM GRAINED, POORLY CEMENTED
SM
SA
AL
EI
CR
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
APPENDIX: B.2
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
PROJECT: 2022239DRAFTED BY: AR
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~88.3%, N60 ~ 88.360*N~1.47*N
LOGGED BY:
LOG OF BORING B-2
AUG 13, 2021
± 165 NGVD 29
N/A
FRASTE PL-G HAMMER: 140 LBS., DROP: 30 IN (AUTO)
6-INCH HOLLOW STEM AUGER AR
MS/GD
55
10
10
24
33
7
8
9
5
8
9
15
10
12
7
16
19
-
--
-
-
-z -
-
-
-
--
-
-
-
J l.
-
-
-
'
-/
--
-
-z -
-
-
-
-7 -
--
-
-
A4~1 ~--. • •
35
40
45
50
55
60
30
62
OLD PARALIC DEPOSITS CONTINUED (Qop): SILTY SAND; ORANGE BROWN, MOIST, VERY
DENSE, FINE GRAINED, MODERATELY CEMENTED
SM
BORING TERMINATED AT 31½ FT. NO GROUNDWATER ENCOUNTERED.
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
APPENDIX: B.3
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
PROJECT: 2022239DRAFTED BY: AR
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~88.3%, N60 ~ 88.360*N~1.47*N
LOGGED BY:
CONTINUED LOG OF BORING B-2
AUG 13, 2021
± 165 NGVD 29
N/A
FRASTE PL-G HAMMER: 140 LBS., DROP: 30 IN (AUTO)
6-INCH HOLLOW STEM AUGER AR
MS/GD
1718
24
-
--
-I
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
A4~1 ~--. • •
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
5
10
15
20
25
30
0
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
BORING TERMINATED AT 16½ FT. NO GROUNDWATER ENCOUNTERED
3 IN OF ASPHALT CONCRETE
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~95.7%, N60 ~ 95.760*N~1.6*N
LOGGED BY:
LOG OF BORING B-3
MAY 24, 2023
± 162½ NGVD 29
N/A
WARHAWK LAR HAMMER: 140 LBS., DROP: 30 IN (AUTO)
4½-INCH SOLID FLIGHT AUGER DM
GD
910
14 38
14
21
28 78
DARK YELLOWISH BROWN AND BROWN, VERY DENSE
APPENDIX: B.4
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
PROJECT: 2022239DRAFTED BY: GN
OLD PARALIC DEPOSITS (Qop): SILTY SAND; DARK YELLOWISH BROWN, MOIST, DENSE,
FINE TO MEDIUM GRAINED
SM
6
8
8 26
CL FILL (af): SANDY CLAY; DARK GRAY AND LIGHT GRAY, MOIST, STIFF, FINE TO MEDIUM
GRAINED SAND
SILTY SAND; BROWN, MOIST, MEDIUM DENSE, FINE TO MEDIUM GRAINEDSM
CLAYEY SAND; GRAY TO BLACK, MOIST, MEDIUM DENSE, FINE TO COARSE GRAINEDSC
SILTY SAND; PALE OLIVE AND GRAY, MOIST, MEDIUM DENSE, FINE TO MEDIUM GRAINEDSM
SA
,-. -.... -x '1--- - - - -....
'I-------
- --
- --
-----------------------------------------------------~--
--
7
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
5
10
15
20
25
30
0
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
BORING TERMINATED AT 11½ FT. NO GROUNDWATER ENCOUNTERED
2 IN OF ASPHALT CONCRETE OVER 10 IN OF AGGREGATE BASE
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~95.7%, N60 ~ 95.760*N~1.6*N
LOGGED BY:
LOG OF BORING B-4
MAY 24, 2023
± 162 NGVD 29
N/A
WARHAWK LAR HAMMER: 140 LBS., DROP: 30 IN (AUTO)
4½-INCH SOLID FLIGHT AUGER DM
GD
13
1830 77
APPENDIX: B.5PROJECT: 2022239DRAFTED BY: GN
SILTY SAND; DARK YELLOWISH BROWN, MOIST, VERY DENSE, FINE TO MEDIUM GRAINEDSM
CL FILL (af): SANDY CLAY; GRAY BROWN AND DARK GRAY, MOIST, STIFF, FINE TO MEDIUM
GRAINED SAND
OLD PARALIC DEPOSITS (Qop): CLAYEY SAND; DARK YELLOWISH BROWN, MOIST, DENSE,
FINE TO MEDIUM GRAINED, TRACE GRAVEL
SC
SA
AL
EI
9
1011 34
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
--
---
-
-
-J 7 -)
'
--
---- - -- - ----- - - - - --------------------------------------->-- -
-
-[7 -
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
A4~1 ~--. • •
DE
P
T
H
(
F
T
)
N60
BL
O
W
S
P
E
R
6
I
N
N
5
10
15
20
25
30
0
BU
L
K
S
A
M
P
L
E
SUMMARY OF SUBSURFACE CONDITIONS
(USCS; COLOR, MOISTURE, DENSITY, GRAIN SIZE, OTHER)
LA
B
T
E
S
T
S
CA
L
/
S
P
T
S
A
M
P
L
E
SOIL DESCRIPTION
MO
I
S
T
U
R
E
(%
)
SO
I
L
C
L
A
S
S
(U
S
C
S
)
DR
Y
D
E
N
S
I
T
Y
(p
c
f
)
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
DRILLING EQUIPMENT:
ELEVATION (FT):
GROUNDWATER DEPTH (FT):
DRILLING METHOD:
DATE DRILLED:SAMPLE METHOD:
NOTES:REVIEWED BY:ETR~95.7%, N60 ~ 95.760*N~1.6*N
LOGGED BY:
LOG OF BORING B-5
MAY 24, 2023
± 162 NGVD 29
N/A
WARHAWK LAR HAMMER: 140 LBS., DROP: 30 IN (AUTO)
4½-INCH SOLID FLIGHT AUGER DM
GD
7
810 29
9
13
15 45
APPENDIX: B.6PROJECT: 2022239DRAFTED BY: GN
OLD PARALIC DEPOSITS (Qop): SILTY SAND; DARK YELLOWISH BROWN, MOIST, DENSE,
FINE TO MEDIUM GRAINED
SM
5
67 21
SC FILL (af): CLAYEY SAND; BROWN, MOIST, MEDIUM DENSE, FINE TO COARSE GRAINED SAND,
SCATTERED FINE GRAVEL, SCATTERED ROOTS
SILTY SAND; DARK GRAYISH BROWN, MOIST, MEDIUM DENSE, FINE TO MEDIUM GRAINED,
TRACE FINE GRAVEL
SM
SA
BORING TERMINATED AT 21½ FT. NO GROUNDWATER ENCOUNTERED
15
2133 86
SANDY CLAY; LIGHT GRAY, MOIST, STIFF, FINE TO MEDIUM GRAINED SANDCL
CLAYEY SAND; MOTTLED DARK GRAY BROWN AND LIGHT GRAY, MOIST, MEDIUM DENSE,
FINE TO COARSE GRAINED, TRACE GRAVEL
CL
CLAYEY SAND; BROWN, MOIST, VERY DENSE, FINE GRAINEDSC
SCATTERED 3 IN COARSE GRAVEL, SMALL COBBLE
SA
CR
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
---x --------------------------------------------------------~---x-- - - - --~---------------------------------------------
~
--------------------------------------------------------~--
--
/__
-----------------------------------------------------~--
Update Geotechnical Investigation
LEGOLAND California Project 2025, Carlsbad, CA 92008
NOVA Project No. 2022239
August 9, 2023
APPENDIX C
LABORATORY TESTING
Laboratory tests were performed in accordance with the generally accepted American Society for Testing and Materials (ASTM) test methods or suggested
procedures. Brief descriptions of the tests performed are presented below:
LAB TEST SUMMARY
·CLASSIFICATION: Field classifications were verified in the laboratory by visual examination. The final soil classifications are in accordance with the
Unified Soils Classification System and are presented on the exploration logs in Appendix B.
·GRADATION ANALYSIS (ASTM D6913): Gradation analyses were performed on representative soil samples in general accordance with ASTM
D422. The grain size distributions of the samples were determined in accordance with ASTM D6913.
·ATTERBERG LIMITS (ASTM D4318): Tests were performed on selected representative fine-grained soil samples to evaluate the liquid limits, plastic
limits, and plasticity indexes in general accordance with ASTM D4318. These test results were utilized to evaluate the soil classification in accordance
with the Unified Soil Classification System.
·EXPANSION INDEX (ASTM D4829): The expansion indexes of selected materials were evaluated in general accordance with ASTM D4829. The
specimens were molded under a specified compactive energy at approximately 50 percent saturation (plus or minus 1 percent). The prepared 1-inch
thick by 4-inch diameter specimens were loaded with a surcharge of 144 pounds per square foot and were inundated with distilled water. Readings of
volumetric swell were made for a period of 24 hours.
·R-VALUE (CT 301 and ASTM D 2844): The resistance value, or R-Value, for near-surface site soils was evaluated in general accordance with California
Test (CT) 301 and ASTM D2844. The sample was prepared and evaluated for exudation pressure and expansion pressure. The equilibrium R-Value is
reported as the lesser or more conservative of the two calculated results.
·CORROSIVITY TEST (CAL. TEST METHOD 417, 422, 643): Soil pH and minimum resistivity tests were performed on representative soil samples in
general accordance with test method CT 643. The sulfate and chloride contents of the selected samples were evaluated in general accordance with
CT 417 and CT 422, respectively.Soil samples not tested are now stored in our laboratory for future reference and evaluation, if needed. Unless
notified to the contrary, samples will be disposed of 60 days from the date of this report.
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
www.usa-nova.com
SBEDVBE SDVOSB SLBE
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.1
A,a~I ~--. . •
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
B-1
0 - 5
SC
37
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.2
28
14
14
Atterberg Limits (ASTM D4318):
Liquid Limit, LL:
Plastic Limit, PL:
Plasticity Index, PI:
<E----Size (Inches) ~.;:: '/ Hydrometer Analysis ' U.S. Standard Sieve Sizes ,.,. '-/
0 0 ~ 0 0 0 ~ 0 "' ?5 ~ ~ ... N ... <O N -- -"' 0 0 0 0 0 0 0
100.0 -z z z z z z z -.-c;c -... I
--~
I I I I
I I I I I I
I I I I I I I
90.0 I I I ) I I I
I I I I I I I
I I I I \ I I I
I I I I \ I I I
I I I I I I I
80.0
I I I I \' I I
I I I I I I I
I I I I I I
Cl 70.0 I I I I I \ I I
C: "iii I I I I I \ I I
1/) I I I I I I I
n:s I I I I I I~ I I ll. 60.0 -I I I I I \ I I
C: I I I I I I I Q) \ u I I I I I I I ... I I I I I I I Q) 50.0 ll. I I I I ,, I I
I I I I I ,, I
I I I I I I
40.0 I I I I I '-I
II T I I ,, I I II
I I I I I • I I I I I
I I I I I
30.0 I I I I I
I I I I I
I I I I I
I I I I I 20.0
I I I I I
I I I I I
I I I I I
10.0 I I I I I
I I I I I
I I I I I
I I I I I
I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
26
13
13
Atterberg Limits (ASTM D4318):
Liquid Limit, LL:
Plastic Limit, PL:
Plasticity Index, PI:
B-2
10 - 15
SC
36
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.3
<E----Size (Inches) ~.;:: '/ Hydrometer Analysis ' U.S. Standard Sieve Sizes ,.,. '-/
0 0 ~ 0 0 0 ~ 0 "' ?5 ~ ~ ... N ... <O N --0 0 0 0 0 0 0
100.0 z z z z z z z .-= -.,.... -...... I I I I I
I I I ll I I I
I I I I I I I
90.0 I I I I \ I I I
I I I I \ I I I
I I I I I I I
I I I I I I I
I I I I \ I I I
80.0
I I I I I I
I I I I I I I
I I I I : , I I
Cl 70.0 I I I I I I
C: \
"iii I I I I I I I
1/) I I I I I I. I I
n:s I I I I I \ I I ll. 60.0 -I I I I I I I
C: I I I I I \ I I Q) u I I I I I \ I I ... I I I I I I I Q) 50.0 I\
ll. I I I I I ,, I
I I I I I -I
I I I I I I
40.0 I I I I I ' I
II T I I ,, I I ~" I I I I I
I I I I I
I I I I I
30.0 I I I I I
I I I I I
I I I I I
I I I I I 20.0
I I I I I
I I I I I
I I I I I
10.0 I I I I I
I I I I I
I I I I I
I I I I I
I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
B-3
2½ - 4
SC
30
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.4
<E---Size (Inches) ~ ~ ' / Hydrometer Analysis ' U.S. Standard Sieve Sizes ,.,., ,.,.
0 0 ... 0 0 0 0 ~ 0
"' ~ ~ ~ -N ... <O N - -
g 0 0 0 0 0 0
100.0 z z z z z z -I I ' 'I I I I I
I I ._ I I I I
I I I I I I
90.0 I I I I I I I
I I I \ I I I I
I I I I I I I
I I I \ I I I I
I I I \' I I I
80.0 ~ I I I I I I
I I I ,, I I I
I I I I I I I
C> 70.0 I I I I I I I
C: "iii I I I I ,, I I I
f/l I I I I I I I ra I I I I I [\ I I I 11. 60.0 -I I I I I I I I I C: I I I I I I I I Cl) u I I I I I ,, I I ... I I I I I I I I Cl) 50.0 11. I I I I I ,\ I I
I I I I I I 1. I I
I I I I I I ' I I
40.0 I I I I I I ' I I
II T I I ,, I ,, II
I I I I I I t-., I
I I I I I I I
I I I I I I ,-I
30.0 I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I 20.0
I I I I I I I
I I I I I I I
I I I I I I I
10.0 I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
26
11
15
Atterberg Limits (ASTM D4318):
Liquid Limit, LL:
Plastic Limit, PL:
Plasticity Index, PI:
B-4
4 - 8
SC
37
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.5
<E---Size (Inches) ~ ~ ' / Hydrometer Analysis ' U.S. Standard Sieve Sizes ,.,., ,.,.
0 0 ... 0 0 0 0 ~ 0
"' ~ ~ ~ -N ... <O N - -
-CC> 0 0 0 0 0 0 0
100.0 -z z z z z z z -... ----.. I --. I I I I
I I ~-. I I I
I I I I I I
90.0 I I I I I I I
I I I I ~ I I
I I I I :, I I
I I I I I I
I I I I I \1 I I
80.0 • I I I I I \ I I
I I I I I I I
I I I I I \' I
C> 70.0 I I I I I ,, I
C: "iii I I I I I ·~ I
f/l I I I I I ,, I ra I I I I I I I I 11. 60.0 -I I I I I I ~ I C: I I I I I I I Cl) u I I I I I I \ I ... I I I I I I \ I Cl) 50.0 11. I I I I I
---.
I I
I I I I I I I
I I I I I I ' I
40.0 I I I I I I ' I
II T I I ,, I I ~. I I I I I I
I I I I I I
I I I I I I
30.0 I I I I I I
I I I I I I
I I I I I I
I I I I I I 20.0
I I I I I I
I I I I I I
I I I I I I
10.0 I I I I I I
I I I I I I
I I I I I I
I I I I I I
I I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
B-5
1 - 3
SC
37
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.6
~ Size (Inches) -----?..,:: ' ~ Hydrometer Analysis ' U.S. Standard Sieve Sizes ,,., ,,.
0 0 ~ 0 0 0 ~ 0
"' :,;!: S! ~ .,. N .,. co N
~ ~ "' g ci ci ci ci ci ci
100.0 z z z z z z -I I ... ~ I I I I I
I I I ,, I I I I
I I I .. , I I I I
90.0 I I I I I I I I
I I I I ~ I I I
I I I I I I I
I I I I 1\ I I I
I I I I I \ I I I
80.0 • I I I I I \ I I I
I I I I I I I I
I I I I I ,, I I
Cl 70.0 I I I I I I I
C: II
'iii I I I I I ,, I I
VI I I I I I I ' I I
cu I I I I I I I I a. 60.0 1, I, I I II I It I 1,
'E I I I I I I \ I I
Cl) I I I I I I \ I I
() I I I I I I I I ... I I I I I I ' I I Cl) 50.0 a. ._ I I I I I I I
I I I I I I I I
I I I I I I ,, I
40.0 I I I I I I I ' I
II ~ I I II I I ~II
I I I I I I I • I I I I I I I
I I I I I I I
30.0 I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I 20.0
I I I I I I I
I I I I I I I
I I I I I I I
10.0 I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
CLASSIFICATION TEST RESULTS
Gravel Sand
Coarse FineMediumCoarseFine
Silt or Clay
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample Location:
Depth (ft):
USCS Soil Type:
Passing No. 200 (%):
B-5
9 - 12
SC
26
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.7
<E----Size (Inches) -----;;> .:: ~ ~ Hydrometer Analysis ~ U.S. Standard Sieve Sizes , ' ,
0 0
"' ~ 0 0 0 ~ 0
~ '1: ~ ~ N "' <D N
~ ~ (') ~ (') 0 0 0 0 0 0 0
100.0 -z z z z z z z ------... I I I I I I
I -....._ I I I I I
I I I I I I
90.0 I I ' I I I I I
I I ,1 I I I I
I I .. I I I I
I I I I I I I
I I I I I I 80.0
I I I I \ I I I
I I I I • I I I
I I I I I I I
Cl 70.0 I I I I I I I
C: II T I I , I II
"iii I I I I I~ I I
Ill I I I I I I I I
Ill I I I I I I I Q. 60.0 I, ' I I ' ' I, -I I I I I \ I I C: I I I I I I I QI \ (,) I I I I I I I ... I I I I I ~ I I QI 50.0 Q. \ I I I I I I I
I I I I I t\ I
I I I I I I
40.0 I I I I I I I
II I I I I 11
I I I I I I \ I
I I I I I I I
I I I I I I I
30.0 I I I I I I I
I I I I I I
I I I I I I
I I I I I I I 20.0
I I I I I I I
I I I I I I I
I I I I I I I
10.0 I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
I I I I I I I
0.0
100 10 1 0.1 0.01 0.001
Grain Size (mm)
I I I I I I I
j,a~I ~--. . .
LAB TEST RESULTS
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
Sample
Location
Expansion
Index
Expansion Index (ASTM D4829)
Sample Depth
(ft.)
Expansion
Potential
Expansion
Potential
Classification of Expansive Soil (ASTM D4829)
Expansion
Index
0-20
21-50
51-90
91-130
>130
Very Low
Low
Medium
High
Very High
B-1 00 - 5 Very Low
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.8
B-2 210 - 15 Very Low
B-4 54 - 8 Very Low
j,a~I ~--. . .
LAB TEST RESULTS
Corrosivity (Cal. Test Method 417,422,643)
Sample
Location
Sample Depth
pH
Resistivity Sulfate Content Chloride Content
(ppm)(%)(Ohm-cm)(ft.)(ppm)(%)
Water-Soluble Sulfate Exposure (ACI 318 Table 19.3.1.1 and Table 19.3.2.1)
Water-Soluble Sulfate (SO4)
in Soil (% by Weight)
Exposure
Class
Cement Type
(ASTM C150)
Exposure
Severity
Max.
W/C
Min. fc'
(psi)
SO4 < 0.10
0.10 ≤ SO4 < 0.20
0.20 ≤ SO4 ≤ 0.20
SO4 > 2.00
N/A
Moderate
Severe
Very Severe
S0
S1
S2
S3
No type restriction
II
V
V plus pozzolan or slag cement
N/A
0.50
0.45
0.45
2,500
4,000
4,500
4,500
NOVA
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION
4373 Viewridge Avenue, Suite BSan Diego, CA 92123P: 858.292.7575
www.usa-nova.com
944 Calle Amanecer, Suite FSan Clemente, CA 92673P: 949.388.7710
SBEDVBE SDVOSB SLBE
10 - 15 8.0 1500 42B-1 0.004 32 0.003
DRAFTED BY: GN PROJECT: 2022239
LEGOLAND CALIFORNIA PROJECT 2025
ONE LEGOLAND DRIVE
CARLSBAD, CA 92008
REVIEWED BY: GD APPENDIX: C.9
10 - 15 7.7 990 110B-2 0.011 85 0.009
9 - 12 7.4 1990 24B-5 0.002 72 0.007
Sample
Location R-Value
Sample
Depth
(ft.)
R-Value (Cal. Test Method 301 & ASTM D2844)
B-1 160 - 5
j,a~I ~--. . .
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION DVBE SBE SDVOSB SLBE
4373 Viewridge Avenue, Suite B
San Diego, CA 92123
P: 858.292.7575
usa-nova.com 16610 Aston Street
Irvine, CA 92606
P: 949.388.7710
Flora Liu, Senior Project Manager July 19, 2024
Merlin Entertainment Group NOVA Project No. 2022239
c/o LEGOLAND California LLC
One Legoland Drive
Carlsbad, California 92009
Subject: Geotechnical Addendum
Update Grading and Foundation Recommendations
LEGOLAND Rollercoaster/Airboats
One Legoland Drive
Carlsbad, California
References: NOVA (2023), Update Geotechnical Investigation, LEGOLAND California Project 2025,
One Legoland, Carlsbad, CA, NOVA Project No. 2022239, August 9.
Leighton and Associates, Inc. (1998), Final As-Graded Report of Rough-Grading, LEGO
Family Park, Carlsbad, California, Project No. 4960151-003, February 10.
Dear Ms. Liu:
NOVA Services, Inc. (NOVA) is pleased to present this geotechnical addendum to provide updated
grading and foundation recommendations for the LEGOLAND Rollercoaster/Airboats project. Based
on our review of the reference as-graded geotechnical report for the site (Leighton, 1998), it is NOVA’s
understanding that the existing fill beneath the proposed roller coaster and airboat ride was placed as
engineered, compacted fill. Revised grading and foundation recommendations are provided below.
Proposed Airboat Ride
As indicated in the project geotechnical report, the proposed airboat ride can be supported on shallow
spread footings or a mat foundation with bottom levels bearing entirely on compacted fill. The
foundation recommendations provided in our geotechnical report for the airboat ride remain
applicable. Remedial grading recommendations for the various building elements are provided below.
Remedial Grading – Slabs-on-Grade
Existing soils should be excavated to a depth of 2 feet below planned pad grade elevation.
Horizontally, excavations should extend 5 feet outside the planned perimeter foundations or up to
existing improvements or the limits of grading, whichever is less. NOVA should observe conditions
exposed in the bottom of the excavation to determine if additional excavation is recommended. The
resulting surface should then be scarified to a depth of 6 to 8 inches, moisture conditioned to near
optimum moisture content, and compacted to at least 90% relative compaction. The excavation should
then be filled to the finished pad grade with compacted fill having an expansion index (EI) of 50 or
less.
Geotechnical Addendum – Update Grading and Foundation Recommendations
LEGOLAND Rollercoaster/Airboats
NOVA Project No. 2022239
July 19, 2024
2
Remedial Grading- Spread Footings Supported on Compacted Fill
Existing soils should be excavated to a depth of 1 foot below bottom of footing. Horizontally,
excavations should extend the width of the footing. NOVA should observe conditions exposed in the
bottom of the excavation to determine if additional excavation is recommended. The resulting surface
should then be scarified to a depth of 6 to 8 inches, moisture conditioned to near optimum moisture
content, and compacted to at least 90% relative compaction. The excavation should then be filled to
the finished pad grade with compacted fill having an expansion index (EI) of 50 or less.
Remedial Grading - Mat Foundations Supported on Compacted Fill
Existing soils beneath the bottom of mat should be excavated to a depth of 1 foot below bottom of
mat. Horizontally, excavations should extend 5 feet outside the planned perimeter of the mat or up to
existing improvements or the limits of grading, whichever is less. NOVA should observe conditions
exposed in the bottom of the excavation to determine if additional excavation is recommended. The
resulting surface should then be scarified to a depth of 6 to 8 inches, moisture conditioned to near
optimum moisture content, and compacted to at least 90% relative compaction. The excavation should
then be filled to the finished pad grade with compacted fill having an expansion index (EI) of 50 or
less.
Proposed Rollercoaster Building
The proposed rollercoaster building can be supported on shallow spread footings or a mat foundation
with bottom levels bearing entirely on compacted fill. The foundation recommendations provided in
our geotechnical report for spread footings and mat foundations are applicable to the roller coaster
building. Based on the results of our field investigation, a transition from shallow fill to deep fill exists
beneath the proposed rollercoaster building pad. Remedial grading recommendations for the portions
of the building pad underlain by shallow fill and deep fill are provided below.
Remedial Grading - Spread Footings or Mat Foundations Underlain by Shallow Fill
To mitigate the potential for adverse settlement due to transitions from shallow fill to deep fill, the old
paralic deposits should be excavated and replaced with compacted fill to provide a relatively uniform
thickness of compacted fill beneath the entire building and reduce the potential for adverse differential
settlement. The depth of formation excavation should be at least 5 feet below finished pad grade, at
least 3 feet below the deepest footing/mat foundation bottom elevation, or to a depth of H/2, whichever
is deeper, where H is the greatest depth of fill beneath the building. Horizontally, excavations should
extend at least 5 feet outside the planned perimeter building foundations or up to existing
improvements, whichever is less. Where practical, the bottom of excavations should be sloped toward
the fill portion of the site and away from its center. NOVA should observe the conditions exposed in
the bottom of excavations to evaluate whether additional excavation is recommended. The excavation
should then be filled to the finished pad grade with suitable compacted fill.
Geotechnical Addendum – Update Grading and Foundation Recommendations
LEGOLAND Rollercoaster/Airboats
NOVA Project No. 2022239
July 19, 2024
3
Remedial Grading - Spread Footings or Mat Foundations Underlain by Deep Fill
Slabs on Grade
Existing soils should be excavated to a depth of 2 feet below planned pad grade elevation.
Horizontally, excavations should extend 5 feet outside the planned perimeter foundations or
up to existing improvements or the limits of grading, whichever is less. NOVA should observe
conditions exposed in the bottom of the excavation to determine if additional excavation is
recommended. The resulting surface should then be scarified to a depth of 6 to 8 inches,
moisture conditioned to near optimum moisture content, and compacted to at least 90%
relative compaction. The excavation should then be filled to the finished pad grade with
compacted fill having an expansion index (EI) of 50 or less.
Spread Footings Supported on Compacted Fill
Existing soils should be excavated to a depth of 1 foot below bottom of footing. Horizontally,
excavations should extend the width of the footing. NOVA should observe conditions exposed
in the bottom of the excavation to determine if additional excavation is recommended. The
resulting surface should then be scarified to a depth of 6 to 8 inches, moisture conditioned to
near optimum moisture content, and compacted to at least 90% relative compaction. The
excavation should then be filled to the finished pad grade with compacted fill having an
expansion index (EI) of 50 or less.
Mat Foundations Supported on Compacted Fill
Existing soils beneath the bottom of mat should be excavated to a depth of 1 foot below bottom
of mat. Horizontally, excavations should extend 5 feet outside the planned perimeter of the mat
or up to existing improvements or the limits of grading, whichever is less. NOVA should
observe conditions exposed in the bottom of the excavation to determine if additional
excavation is recommended. The resulting surface should then be scarified to a depth of 6 to
8 inches, moisture conditioned to near optimum moisture content, and compacted to at least
90% relative compaction. The excavation should then be filled to the finished pad grade with
compacted fill having an expansion index (EI) of 50 or less.
As an alternative to supporting the rollercoaster building on shallow foundations (spread footings
and/or mat foundations) with bottom levels bearing on compacted fill as described above, the
proposed roller coaster building can be supported on spread footings with bottom levels bearing on
aggregate piers or 3-sack sand/cement slurry that extends down to old paralic deposits or on CIDH
concrete piles embedded in old paralic deposits as detailed in our geotechnical report (NOVA, 2023).
Geotechnical Addendum – Update Grading and Foundation Recommendations
LEGOLAND Rollercoaster/Airboats
NOVA Project No. 2022239
July 19, 2024
4
If you have any questions, please call us at 858.292.7575 x 417.
Sincerely,
NOVA Services, Inc.
__________________________ ___________________________
Gillian Carzzarella Dean, PE, GE Thomas B. Canady, PE
Senior Geotechnical Engineer Principal Engineer
GEOTECHNICAL
MATERIALS
SPECIAL INSPECTION DVBE SBE SDVOSB SLBE
4373 Viewridge Avenue, Suite B San Diego, CA 92123 P: 858.292.7575
usa-nova.com 16610 Aston Street Irvine, CA 92606 P: 949.388.7710
Flora Liu, Senior Project Manager July 22, 2024
Merlin Entertainment Group NOVA Project No. 2022239
c/o LEGOLAND California LLC
One Legoland Drive
Carlsbad, California 92009
Subject: Responses to City of Carlsbad Geotechnical Report Review Comments (1st Review)
LEGOLAND Roller Coaster/Airboats
One Legoland Drive
Carlsbad, California
References: City of Carlsbad (2024), Geotechnical Report Review, LEGOLAND Roller Coaster/
Airboats (1st Review), Project ID SDP2023-0012, Grading Permit No. GR2024-0009,
May 14.
NOVA Services, Inc. (NOVA) (2023), Update Geotechnical Investigation, LEGOLAND
California Project 2025, One Legoland Drive, Carlsbad, CA 92008, NOVA Project No.
2022239, August 9.
NOVA Services, Inc. (NOVA) (2024), Update Grading and Foundation
Recommendations, LEGOLAND Rollercoaster/Airboats, One Legoland Drive,
Carlsbad, California, NOVA Project No. 2022239, July 19.
Commercial Development Resources (CDR) (2024), Private Grading Plans, Legoland California Project 2025, July 22.
Dear Flora Liu:
NOVA Services, Inc. (NOVA) prepared this letter to respond to the referenced geotechnical report
review comments from the City of Carlsbad (2024) for the LEGOLAND California Roller Coaster/
Airboat project. NOVA is retained by the Merlin Entertainment Group as the geotechnical consultant
of record for the project. The review comments and our responses are provided below.
Comment 1: Please review the most current grading and building plans for the project and provide any
additional and/or revised recommendations for the proposed project as necessary.
Response: NOVA reviewed the current grading plans (CDR, 2024). NOVA’s review was limited to the
geotechnical aspects of the plans. Based on our review, it is NOVA’s opinion that the plans have been
prepared in accordance with the recommendations contained in the project’s geotechnical reports
(NOVA, 2023; 2024). Additional analysis and/or recommendations are not necessary at this time.
Responses to City of Carlsbad Geotechnical Report Review Comments (1st Review) LEGOLAND Roller Coaster/Airboats, Carlsbad, CA NOVA Project No. 2022239
July 22, 2024
2
Comment 2: The results of strength (direct shear) testing of the on-site soils is not provided in the
report. Please provide the appropriate laboratory testing to substantiate the values for bearing
capacity, passive pressure, coefficient of friction, and active/at-rest earth pressures that are presented
in the report (as they exceed values of Class 4 and 5 soils presented in Tables 1806.2 and 1610.1 of
the 2022 California Building Code). If presumptive values are being recommended by the consultant,
please state the reference and use values consistent with the appropriate soil type in Tables 1806.2
and 1610.1 of the 2022 California Building Code. As it appears that the on-site soils area generally
consistent with the Class 4 soils per Table 1806.2, please provide a thorough description and support
of the basis and /or results of laboratory (strength) testing to justify the use of any geotechnical design
parameters that exceed the values of Class 4 soils in Table 1806.2.
Response: The passive pressure provided is based on the recorded blow counts of the fill encountered
during exploration of the entire LEGOLAND amusement park. The fill beneath the site generally
consists of medium dense to very dense silty and clayey sand and stiff sandy clay. The recorded SPT
blow counts were corrected to a 60% energy transfer ratio (N60). The corrected SPT value was then
utilized to obtain equivalent friction angles after Meyerhof (1956). Table 1 summarizes the relationship
between SPT N Value, relative density, and effective stress friction angle (Meyerhof, 1956).
Table 1. Relationship between SPT N Value, Relative Density, and Effective Friction Angle (Meyerhof, 1956)
State of Packing
Relative Density
(%)
N60
(blows/ft)
Static Cone Tip Resistance, qc
(tsf)
Effective Stress Friction Angle (degrees)
Very Loose < 20 < 4 < 20 < 30
Loose 20 – 40 4 – 10 20 – 40 30 – 35
Medium 40 – 60 10 – 30 40 – 120 35 – 40
Dense 60 – 80 30 – 50 120 – 200 40 – 45
Very Dense > 80 > 50 > 200 > 45
Passive pressures provided for conventional foundations were based on foundations embedded into
compacted fill. Based on NOVA’s experience with compacted fill at LEGOLAND, a minimum 90%
relative compaction would typically result in dense soil with a relative density greater than 50%, which
correlate to a friction angle greater than 35 degrees. A friction angle of 33 degrees and unit weight of
120 pounds per cubic foot (pcf) were used in conjunction with Rankine’s theory to calculate passive
pressure. It should be noted the fills will have some cohesion due to the fines content; however,
cohesion was conservatively ignored in the calculations. Utilizing a conservative friction angle of 33
degrees and a unit weight of 120 pcf, the calculated passive pressure is 407 pcf, greater than the
recommended value of 350 pcf. Based on NAVFAC DM-7.02, page 7.2-63, Table 1: Ultimate Friction
Factors and Adhesion for Dissimilar Materials, the coefficient of friction, or friction factor, for silty of
clayey sand ranges from 0.35 to 0.45. Accordingly, a coefficient of friction value of 0.35 was selected
for footings and mat foundations bearing on compacted fill.
To calculate allowable bearing capacity, a conservative friction angle of 33 degrees, a unit weight of
120 pcf, and a factor of safety of 3 were used. The allowable bearing capacities for the minimum footing
Responses to City of Carlsbad Geotechnical Report Review Comments (1st Review) LEGOLAND Roller Coaster/Airboats, Carlsbad, CA NOVA Project No. 2022239
July 22, 2024
3
depth (18 inches) and width (24 inches) per the Terzaghi and Vesic and methods are 3,265 psf and
3,289 psf, respectively. Note that the calculated bearing capacities are greater than the provided
allowable bearing pressure of 2,500 psf for footings supported on compacted fill.
Comment 3: Please provide revised CIDH pile parameters as necessary based on the results of the strength testing request in Comment #2 above.
Response: The selected friction angle, unit weight and cohesion values provided above are applicable
to CIDH piles and were used to develop the CIDH pile recommendations provided in our geotechnical
report. Accordingly, it is NOVA’s opinion that revised CIDH pile parameters/recommendations are not
necessary.
Comment 4: The text of the report under “Conclusions” (page 12) and Expansive Soil (page 14) indicates the on-site soils are considered to have a “Very Low” expansion potential (EI = 0 to 5),
however other pages in the report under Remedial Grading and Pedestrian Hardscape (pages 14 and
19) provide grading and foundation recommendations for soils with an Expansion Index less than 50 (“Low” expansion potential). As soils with expansion index (EI) over 20 are considered expansive and
require mitigation in accordance with Sections 1803.5.3 and 1808.6 of the 2022 CBC, please revise
the report as necessary to recommend the use of soils with an Expansion Index less than 20 or provide foundation and floor slab recommendations to address expansive soils (for soils with an EI between
20 and 50) in accordance with Section 1808.6 and the 2022 California Building Code. Please provide
the methods (1806.1 through 1806.4) and any geotechnical parameters (Effective Plasticity Index, etc.) that are being recommended to address expansive soils (for soils with an EI between 20 and 50) and
satisfy Section 1808.6 of the 2022 California Building Code for the proposed slab-on-ground
construction; and provide a statement that the foundations system for the proposed structure will meet the requirements of Section 1808.6 of the 2022 California Building Code.
Response: The report recommendations conservatively account for expansive soils up to an EI of 50,
despite the on-site soils having a very low expansion potential. The foundation recommendations will
meet the requirements of Section 1808.6 of the 2022 California Building Code (CBC).
Comment 5: There are currently no recommendations in the report for interior concrete floor slab and
underlayment. Please provide geotechnical recommendations as necessary for interior concrete floor
slabs and associated underlayment/vapor retarder based on the results of comment #4 above to
address expansive soils.
Response: Interior concrete slabs-on-grade should be underlain by at least 2 feet of material with an
EI of 50 or less. The top 12 inches of subgrade soils should be scarified, moisture conditioned to near
optimum moisture content, and compacted to at least 90% relative compaction. If competent very old
paralic deposits are exposed, scarification and recompaction need not be performed. Subgrade
preparation should be performed immediately prior to placement of the concrete slab.
We recommend that concrete slabs-on-grade be at least 5 inches thick and reinforced with at least
No. 4 bars at 18 inches on center each way. To reduce the potential for excessive cracking, concrete
slabs should be provided with construction or ‘weakened plane’ joints at frequent intervals. The project
structural engineer should design on-grade building slabs and joint spacing.
Responses to City of Carlsbad Geotechnical Report Review Comments (1st Review) LEGOLAND Roller Coaster/Airboats, Carlsbad, CA NOVA Project No. 2022239
July 22, 2024
4
Moisture protection should be installed beneath slabs where moisture-sensitive floor coverings will be
used. The project architect should review the tolerable moisture transmission rate of the proposed floor
covering and specify an appropriate moisture protection system. Typically, a plastic vapor barrier is
used. Minimum 15-mil plastic is recommended. The plastic should comply with ASTM E1745. The
vapor barrier installation should comply with ASTM E1643. The slab can be placed directly on the
vapor barrier.
Comment 6: Please provide the minimum reinforcement requirements for new foundations from a geotechnical standpoint.
Response: Minimum one No. 4 bar at top and bottom are recommended. However, the project
structural engineer should design the actual reinforcement of foundations.
Comment 7: Please provide the Seismic Design Category for the project in accordance with Section 1613 of the 2022 California Building Code and ASCE 7-16.
Response: The Seismic Design Category for the project is ‘D’ in accordance with Section 1613 of the 2022 CBC and ASCE 7-16.
Comment 8: Please provide a complete summery list of the geotechnical observation/testing services
that should be performed as part of the construction of this proposed development.
Response: The geotechnical observation and testing services during the construction of the proposed
development should conform to the local jurisdictional agency and Chapter 17 of the 2022 CBC. We
recommend that the following geotechnical observation and testing services be performed during site
grading and earthwork construction:
• Attend the grading preconstruction meeting.
• Observe ground preparation prior to fill placement.
• Observe and map the geologic conditions exposed during grading.
• Observe placement and compaction of fill, backfill, and paving materials and perform field
density testing.
• Perform laboratory tests on fill, backfill, and paving materials.
• Observe foundation excavations to evaluate conformance with the project plans and
geotechnical recommendations.
• Prepare daily field reports summarizing the day's activity with regard to earthwork.
• Prepare supplemental reports and letters as needed and a final report upon completion of the
earthwork summarizing the results of our geotechnical observation and testing and our
conclusions regarding conformance with the project plans and specifications.
Responses to City of Carlsbad Geotechnical Report Review Comments (1st Review) LEGOLAND Roller Coaster/Airboats, Carlsbad, CA NOVA Project No. 2022239
July 22, 2024
5
Closure
NOVA appreciates the opportunity to be of continued service to Merlin Entertainment Group on this
project. If you have any questions regarding this letter, please call us at 858.292.7575 x 406.
Sincerely, NOVA Services, Inc.
_________________________ _________________________
Gillian Carzzarella Dean, PE, GE Tom Canady, PE
Senior Geotechnical Engineer Principal Engineer