HomeMy WebLinkAboutCUP 06-11A; PACIFIC RIDGE SCHOOL EXPANSION; ENVIRONMENTAL NOISE STUDY FOR THE PROPOSED PACIFIC RIDGE SCHOOL EXPANSION; 2008-07-03WIELAND
ACOUSTICS
noise ri vibration consultants
WIELAND ACOUSTICS, INC.
2691 Richter Avenue, Suite 114
Irvine, CA 92606
Tel: 949.474.1222
Fax: 949.474.9122
www.wlelandacoustks.com
Environmental Noise Study for the Proposed
Pacific Ridge School Expansion
In the City of Carlsbad
Project File 08.043.00
July 3, 2008
RECEIVED
Prepared for:
Pacific Ridge School
6269 El Fuerte Street
Carlsbad, CA 92009
Prepared by:
Jonathan Higginson, Senior Consultant
David L. Wieland, Principal Consultant
JUL. 09 2008
CITY OF CARLSBAD
PLANNING DEPT
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WIELAND
ACOUSTICS
noise & vibration consuta,iti
PACIFIC RIDGE SCHOOL Proposed School Expansion Project File 08.043.00 - FINAL
Table of Contents
1 EXECUTIVE SUMMARY........................................................................................................1
2 INTRODUCTION/PROJECT DESCRIPTION ..............................................................................3
3 FUNDAMENTALS OF SOUND ...............................................................................................9
4 NOISE DESCRIPTORS ...........................................................................................................9
4.1 DECIBELS..................................................................................................................................9
4.2 A-WEIGHTING ........................................................................................................................10
4.3 EQUIVALENT SOUND LEVEL (Lw) ................................................................................................10
4.4 COMMUNITY NOISE EQUIVALENT LEVEL (CNEL)...........................................................................10
5 NOISE CRITERIA .................................................................................................................12
5.1 STATE OF CALIFORNIA OFFICE OF PLANNING AND RESEARCH...........................................................12
5.2 CALIFORNIA CODE OF REGULATIONS...........................................................................................12
5.3 CALIFORNIA STREETS AND HIGHWAYS CODE.................................................................................12
5.4 CITY OF CARLSBAD MUNICIPAL CODE .......................................................................................... 12
5.5 CITY OF CARLSBAD GENERAL PLAN .............................................................................................13
5.6 CITY OF CARLSBAD NOISE GUIDELINES MANUAL...........................................................................13
6 THRESHOLDS OF SIGNIFICANCE ..........................................................................................13
7 EXISTING NOISE ENVIRONMENT.........................................................................................14
7.1 NOISE MEASUREMENTS............................................................................................................14
7.2 TRAFFIC .................................................................................................................................16
7.3 MCCLELLAN-PALOMAR AIRPORT................................................................................................16
8 FUTURE NOISE ENVIRONMENT...........................................................................................18
8.1 PROJECT CONSTRUCTION ..........................................................................................................18
8.2 PROJECT OPERATION ........................................................................................... . .................... 20
8.2.1 Traffic.........................................................................................................................20
8.2.2 On-Site Noise Sources.................................................................................................21
9 IMPACTS ON THE PROJECT SITE .......................................................................................... 22
9.1 TRAFFIC NOISE ........................................................................................................................22
9.2 MCCLELLAN-PALOMAR AIRPORT................................................................................................25
10 ASSESSMENT OF IMPACT ...................................................................................................25
11 MITIGATION MEASURES ....................................................................................................25
11.1 MITIGATION OF SIGNIFICANT IMPACTS DUE TO PROJECT OPERATIONS .............................................26
11.2 REDUCTION OF SIGNIFICANT IMPACTS DUE TO PROJECT CONSTRUCTION ..........................................26
11.3 MITIGATION OF SIGNIFICANT IMPACTS AT EXTERIOR PROJECT AREAS ...............................................26
11.4 MITIGATION OF SIGNIFICANT IMPACTS WITHIN PROJECT BUILDINGS................................................27
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WIELAND
ACOUSTICS
noise vibration Conslittilits
PACIFIC RIDGE SCHOOL
Proposed School Expansion Project File 08.043.00 - FINAL
12 IMPACTS AFTER MITIGATION .............................................................................................29
13 PROJECT ALTERNATIVE ......................................................................................................29
14 REFERENCES ......................................................................................................................29
List of Tables
Table 7-1. Summary of Ambient Noise Measurements ......................................................................16
Table 7-2. Summary of Existing Traffic Data........................................................................................16
Table 8-1. Construction Noise Levels ..................................................................................................19
Table 8-2. Summary of Future Traffic Data .........................................................................................20
List of Figures
Figure 2-1. Project Location...................................................................................................................3
Figure 2-2. Existing Campus Layout.......................................................................................................4
Figure 2-3. Phase I Campus Expansion ..................................................................................................6
Figure 2-4. Phase II Campus Expansion .................................................................................................7
Figure 2-5. Campus Master Plan............................................................................................................8
Figure 4-1. Common Noise Sources and A-Weighted Noise Levels ....................................................11
Figure 4-2. Common CNEL Noise Exposure Levels at Various Locations.............................................11
Figure 7-1. Noise Measurement Locations..........................................................................................15
Figure 7-2. McClellan-Palomar Airport Noise Contours and Relative Location of Project Site...........17
Figure 9-1. Unmitigated Traffic Noise Levels at Project Site from El Fuerte, 1s' Floor........................23
Figure 9-2. Unmitigated Traffic Noise Levels at Project Site from El Fuerte, 2nd Floor .......................24
Figure 11-1. Recommended Sound Barrier at South End of Project Site ...........................................28
List of Appendices
Appendix I. Noise Measurements
Appendix II. Traffic Noise Modeling
Appendix Ill. Construction Noise Modeling
Appendix IV. Operational Noise Modeling
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I Executive Summary
This report identifies and assesses the potential noise impacts associated with the construction and
operation of the Pacific Ridge School (PRS) campus expansion in the City of Carlsbad. The expansion
is planned in phases. Phase I includes relocating the sports field south to a new parcel and providing
temporary space (mobile buildings) for increased student enrollment while construction of
permanent buildings is in progress. Permanent buildings to be constructed include a High School
Building and, subject to availability of funding, a gymnasium. Other Phase I site improvements
include implementing a permanent storm water management plan, increasing the surface parking
count, extending an existing fire access lane, and landscaping. Phase II will focus on the opening of
the High School Building, the demounting and removal of the Phase I mobile buildings, interim open
space development, and student enrollment increases. Phase II also includes the permanent
occupancy of the gymnasium (if not deferred), and surface parking expansion. Future Phases will
then include the construction of a Support Building, an icon building at the gateway to the PRS
campus, and a Middle School building, demounting and removing all remaining mobile buildings,
and final landscaping of the Project site. Final student enrollment is projected at 540 students,
comprised of 180 Middle School students and 360 High School students. The exact timing of the
final construction phases is to be determined but will be completed by 2022. It is noted that one of
PRS's goals is to include a number of green building technologies in the permanent school buildings
- technologies such as passive heating and cooling; it is possible that buildings constructed with
such design elements may provide less noise reduction than standard construction (for example if
there are additional ventilation openings for passive airflow).
In order to identify the existing noise environment, measurements were taken at four locations
throughout the study area. The introduction of new noise sources, such as construction activities
and on-site operations, will result in a change to the noise environment at existing properties in the
vicinity of the Project as well as at the Project site itself.
Using the criteria established in this study, it may be concluded that construction and operation of
the proposed Project will create significant impacts at existing residential properties in the study
area. It may also be concluded that there are significant impacts on the Project site due to future
traffic noise exposures, both at exterior areas of the Project site and within the proposed buildings.
The following measures are recommended to mitigate the significant impacts associated with the
Project:
A 6-foot high sound barrier shall be constructed along the south end of the proposed sports
field.
Doors and windows of school buildings shall be kept closed when noise-generating activities are
taking place inside. If non-standard construction techniques are to be used at future school
buildings, including green building technologies, then plans shall be reviewed by a qualified
acoustical consultant in order to ensure the buildings will provide adequate noise reduction. Any
necessary acoustical upgrades shall be incorporated into the final building plans prior to
construction. A mechanical engineer shall verify that the buildings, with acoustical upgrades,
satisfy any applicable ventilation requirements.
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Mechanical designs for the project shall be analyzed by a qualified acoustical consultant as
necessary to verify that noise levels generated by mechanical equipment comply with the City
noise standards. If mechanical noise levels do not comply with the standards as designed,
additional mitigation measures shall be incorporated to provide compliance.
The sound barrier recommended in Item #1, above, shall be constructed as early as possible in
the school expansion process so that it will also help to shield nearby residences from
subsequent construction noise.
Construction activities shall be limited to the hours and days permitted by the City of Carlsbad.
Pile driving shall not be permitted at the Project site.
All construction and demolition equipment shall be fitted with properly sized mufflers.
Noisy construction equipment items shall be located as far as practicable from the residential
properties to the south and west.
No exterior usable areas (e.g., gardens, sports fields/courts, courtyards, seating areas, dining
areas, etc.) of the PRS campus shall be located in areas with an exterior CNEL greater than 65
dB.
Architectural plans for the future Arts Building shall be reviewed by a qualified acoustical
consultant in order to ensure the building will comply with the City's interior noise standard for
school buildings. Any necessary acoustical upgrades shall be incorporated into the final building
plans prior to construction.
If standard construction techniques are to be used at future school buildings, mechanical
ventilation shall be provided since the interior 1-hour Leq standard of 45 dB(A) is to be met with
windows and doors closed.
If non-standard construction techniques are to be used at future school buildings including
green building technologies, then bulding plans shall be reviewed by a qualified acoustical
consultant in order to ensure the building will comply with the City's interior noise standard for
school buildings. Any necessary acoustical upgrades shall be incorporated into the final building
plans prior to construction. A mechanical engineer shall verify that the buildings, with acoustical
upgrades, satisfy any applicable ventilation requirements.
Significant unavoidable impacts related to construction noise will remain, even after mitigation.
These significant unavoidable impacts are a result of temporary increases in the ambient noise of
more than 3 dB at nearby residential properties.
It is not considered practical or feasible to mitigate these impacts to a less than significant level.
However, the noise may be considered acceptable because the construction will occur within the
time periods permitted by the City of Carlsbad and because the City does not specify construction
noise limits.
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Ys/IELAND PACIFIC RIDGE SCHOOL
ACOUSTI CS Proposed School Expansion
noise & vi brat ion consu[tants Project File 08.04100 - FINAL
2 Introduction/Project Description
The purpose of this study is to identify and assess the potential noise impacts associated with the
construction and operation of the proposed expansion of the Pacific Ridge School (PRS) campus (the
Project) in the City of Carlsbad. The Project is located in the Bressi Ranch community immediately
west of El Fuerte Street between Bressi Ranch Way and Greenhaven Drive. Refer to Figure 2-1 for
the Project location.
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Figure 2-1. Project Location
Figure 2-2 provides the site plan for the existing PRS campus. It is noted that the proposed Project
includes the expansion of the PRS campus onto an additional parcel of land (Parcel 4) immediately
south of the existing campus. The school site will be expanded in phases, described as follows:
Phase I - Academic Year (AY) 3 (2009/2010) - The objectives of this initial phase include relocating
the sports field south to Parcel 4 and providing temporary space for increased student enrollment
from 104 to 330 students, while construction of permanent buildings is in progress. An approximate
37,000 sf, two-story High School Building will be constructed for occupancy in AY4 (2010). The plans
also contemplate construction of an approximate 36,000 Sf gymnasium for AY4 occupancy subject to
availability of funding. As an interim measure during the proposed design, permitting and
construction of the new AY4 facilities (i.e., the High School and gymnasium), PRS proposes the
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Te
Parcel 4
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Figure 2-2. Existing Campus Layout
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temporary use of nine mobile buildings in AY3 and interior modifications to the four existing mobile
buildings. PRS estimates that interim mobile classrooms would be needed for 12 months and then
removed from the site following completion of the permanent AY4 facilities. Existing mobile
buildings will remain actively utilized, housing the Middle School, the Resource Center (library), Art,
Music and Athletic programs on an interim basis. Other proposed site improvements include
implementing a permanent storm water management plan, increasing the surface parking count
from 97 to 105 spaces, extending the fire access lane, and landscaping. The Phase I site plan is
provided in Figure 2-3.
Phase II - AY4 (2010/2011) - This phase will focus on the opening of the High School Building, the
demounting and removal of the nine temporary mobile buildings, interim open space development,
and student enrollment increases from 330 to 435 students. Phase II includes the permanent
occupancy of the gymnasium (if not deferred), occupancy of approximately 22,900 sf of the 37,000
sf High School Building, and minor interior modifications to existing mobile buildings to
accommodate the AY4 Middle School enrollment. Interior fit-up of the balance of the High School
Building will be completed during AY4 to accommodate AYS High School enrollment. Existing mobile
buildings will remain actively utilized, housing enrollment expansion for the Middle School, the
Resource Center and Art, and Music programs on an interim basis. The proposed site improvements
include the interim development of student-oriented open space for student recreation south of the
High School Building and permanent landscaping and surface parking expansion from 105 to 128
spaces. The Phase II site plan is provided in Figure 2-4.
Future Phases - Full occupancy of the High School Building is expected to occur in AYS (2011/2012)
with the student population projected to increase from 435 to 480 students. The four existing
mobile buildings will remain actively utilized, housing the Middle School, as described in Phase II.
Subsequent development is anticipated to occur after AY6. The exact timing of the final construction
phases is to be determined but will be completed by 2022. These phases will include, initially, the
expansion of student support space and the creation of an icon building at the gateway to the PRS
campus. The icon building would be an approximate 9,700 sf, two-story structure to house the
Resource Center, a Black Box Theater, Dance Studio and Audiovisual Studio. Further proposed
development includes the permanent construction of an approximately 14,400 sf, two-story Middle
School, and an approximate 13,800 sf, two-story Support Building housing the campus' Multi-
purpose Building, Resource Library, Art Studio and Music Studio. Final student enrollment is
projected at 540 students, comprised of 180 Middle School students and 360 High School students.
By 2022 all existing mobile buildings will be demounted and removed from the site. The former
mobile building site area will be land banked and redeveloped as a new student-oriented outdoor
recreational area. Proposed site improvements include final landscaping of building courtyards and
the creation of separated exterior dining terraces for the Middle and High School students. Parking
count and site improvements are proposed to remain unmodified at 128 spaces. The campus master
plan is provided in Figure 2-5.
It is noted that one of PRS's goals is to include a number of green building technologies in the
permanent school buildings - technologies such as passive heating and cooling. The details and
extent of such technology is to be determined. It is also anticipated that traditional HVAC systems
would be included for periods when passive heating and cooling is not sufficient.
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I ACOUSTICS Proposed School Expansion
noise & vibration consultants Project File 08.043.00 - FINAL
3 Fundamentals of Sound
Sound may be thought of as mechanical energy of a vibrating object transmitted by pressure waves
through a medium to the human ear. The medium of main concern for environmental noise is air.
Noise is most simply defined as unwanted sound.
In its most basic form, a sound can be described by its frequency and its amplitude. As a sound wave
propagates past a point in the air it causes the air to alternate from a state of compression to a state
of rarefaction. The number of times per second that the wave passes from a state of maximum
compression through a period of rarefaction and back to a state of maximum compression is the
frequency. The amplitude describes the maximum pressure disturbance caused by the wave; that is,
the difference between the "resting" pressure in the air when no sound is present and the pressure
during the state of maximum compression or rarefaction caused by the sound wave.
Frequency is expressed in cycles per second, or Hertz (Hz). One Hertz equals one cycle per second.
High frequencies are sometimes more conveniently expressed in units of kilohertz (kHz) or
thousands of Hertz. The extreme range of frequencies that can be heard by the healthiest human
ear spans from 16 to 20 Hz on the low end to about 20,000 Hz on the high end. Frequencies are
heard as the pitch or tone of sound. High frequencies produce high-pitched sounds; low frequencies
produce low-pitched sounds. Very-low-frequency airborne sound of sufficient amplitude may be felt
before it can be heard, and can be confused with ground-borne vibration. For any given frequency,
an increase in amplitude correlates to an increase in loudness and a decrease in amplitude
correlates to a decrease in loudness.
4 Noise Descriptors
The following sections briefly describe the noise descriptors that will be used throughout this study:
4.1 Decibels
The magnitude of a sound is typically described in terms of sound pressure level (SPL) which refers to
the root-mean-square (rms) pressure of a sound wave and can be measured in units called
microPascals (tPa). However, expressing sound pressure levels in terms of i.tPa would be very
cumbersome since it would require a very wide range of numbers (approximately 20 to 20,000,000
i.LPa over the entire range of human hearing). For this reason, sound pressure levels are stated in
terms of decibels, abbreviated dB. The decibel is a logarithmic unit that describes the ratio of the
actual sound pressure to a reference pressure (20 tPa is the standard reference pressure level for
acoustical measurements in air). Specifically, a sound pressure level, in decibels, is calculated as
follows:
SPL = 201ogo[X),
where X is the actual sound pressure and 20 tPa is the reference pressure.
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Since decibels are logarithmic units, sound pressure levels cannot be added or subtracted by
ordinary arithmetic means. For example, if one automobile produces a sound pressure level of 70 dB
when it passes an observer, two cars passing simultaneously would not produce 140 dB. In fact, they
would combine to produce 73 dB.
4.2 A-Weighting
While sound pressure level defines the amplitude of a sound, this alone is not a reliable indicator of
loudness. Human perception of loudness depends on the characteristics of the human ear. In
particular, the frequency (i.e., pitch) of a sound has a substantial effect on how humans will
respond. Human hearing is limited not only to the range of audible frequencies, but also in the way
it perceives sound pressure levels within that range. In general, the healthy human ear is most
sensitive to sounds between 1,000 Hz and 5,000 Hz, and perceives both higher and lower frequency
sounds of the same magnitude as being less loud. In order to better relate noise to the frequency
response of the human ear, a frequency-dependent rating scale, known as the A-Scale, is used to
adjust (or "weight") the sound level measured by a sound level meter. The resulting sound pressure
level is expressed in A-weighted decibels or dB(A). When people make relative judgments of the
loudness or annoyance of most ordinary everyday sounds, their judgments correlate well with the A-
weighted sound levels of those sounds. A range of noise levels associated with common indoor and
outdoor activities is shown in Figure 4-1.
4.3 Equivalent Sound Level (Leq)
Many noise sources produce levels that fluctuate over time; examples include mechanical
equipment that cycles on and off, or construction work which can vary sporadically. The equivalent
sound level (Lu) describes the average acoustical energy content of noise for an identified period of
time, commonly 1 hour. Thus, the Leq of a time-varying noise and that of a steady noise are the same
if they deliver the same acoustic energy over the duration of the exposure. For many noise sources,
the Leq will vary depending on the time of day - a primary example is traffic noise which rises and
falls depending on the amount of traffic on a given street or freeway.
4.4 Community Noise Equivalent Level (CNEL)
It is recognized that a given level of noise may be more or less tolerable depending on the duration
of the exposure experienced by an individual, as well as the time of day during which the noise
occurs. The community noise equivalent level (CNEL) is a measure of the cumulative 24-hour noise
exposure that considers not only the variation of the A-weighted noise level but also the duration
and the time of day of the disturbance. The CNEL is derived from the twenty-four A-weighted 1-hour
L's that occur in a day, with "penalties" applied to the Leq'S occurring during the evening hours (7
p.m. to 10 p.m.) and nighttime hours (10 p.m. to 7 a.m.) to account for increased noise sensitivity
during these hours. Specifically, the CNEL is calculated by adding 5 dB(A) to each of the evening L,'5,
adding 10 dB(A) to each of the nighttime L's, and then taking the average value for all 24 hours. It
is noted that various state and local agencies have adopted CNEL as the measure of community
noise, including the State Department of Aeronautics and the California Commission on Housing and
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ACOUSTICS
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Threshold of pain— —120 dB(A)
Disco— —110 dB(A)
Textile mill— -
Printing plant— —100 dB(A)
Jackhammer at 50— -
Power lawn mower at 5— —90 dB(A)
Heavy truck at 50— -
Concrete mixer at 50— —80 dB(A)
10dB change generally
Inside car at40 mph — - perceleedaslwiccorhaIfaid
Vacuum cleaner at 10— —70 dB(A)
Car, 60 mph at 100— -
Conversational speech— —60 dB(A) 5 dB change generally
perceived as quite noticeable Large transformer at 5ff— -
Urban residence— —50 dB(A) 3 dill change Is generally barely
perceptible
Small town residence— -
— —40 dB(A) l dill change lspner.11ynot
noticeable Soft whisper at 6— -
- —30dB(A)
NorthrlmofGrandCanyon — -
- —20 dB(A)
- —10dB(A)
Threshold of hearing— LO dB(A)
Figure 4-1. Common Noise Sources and
A- Weighted Noise Levels
PACIFIC RIDGE SCHOOL
Proposed School Expansion
Project File 08.0.43.00 - FINAL
- —90 MI
Next to freeway— -
Los Angeles, 3/4 ml. from LAX— -
- —80 dB
Downtown Los Angeles
- 70 dB
Housing on major street
common standard for noise exposure level
- - In exterior residential areas
Los Angeles, 8 ml. from LAX— -
Old suburban residential area— —60dB
Small town cul-de-sac— —50 dB
Common standard for noise exposure level
- - In Interior residential areas
Farm— —40 dB
- 30 dB
Figure 4-2. Common CNEL Noise Exposure
Levels at Various Locations
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® At anytime on Sundays or holidays (New Year's Day, Memorial Day, Independence Day, Labor
Day, Veterans Day, Thanksgiving Day and Christmas Day).
There are no quantitative standards for noise levels generated by construction activities.
5.5 City of Carlsbad General Plan
Section IV.C.5 of the City's General Plan indicates that it is "the policy of the City that 60 dB CNEL is
the exterior noise level to which all residential units should be mitigated. 65 dB(A) CNEL is the
maximum noise level to which residential units subject to noise from McClellan-Palomar Airport
should be permitted." It further states that "interior noise levels should be mitigated to 45 dB CNEL
when openings to the exterior of the residence are open or closed. If openings are required to be
closed to meet the interior noise standard, then mechanical ventilation shall be provided."
5.6 City of Carlsbad Noise Guidelines Manual
The City of Carlsbad Noise Guidelines Manual states the maximum allowable exterior CNEL at
residential units is 60 dB, except at areas impacted by McClellan Palomar Airport where the
maximum allowable exterior CNEL is 65 dB. Interior noise levels for all residential units shall be
mitigated to 45 dB CNEL when openings to the exterior of the residence are closed. If openings are
required to be closed in order to meet the interior noise standard then mechanical ventilation shall
be provided.
The Manual indicates that an exterior CNEL of up to 65 dB is conditionally acceptable for schools. It
is our understanding that the exterior standard is only for "usable areas" where people would spend
extended periods of time, such as sports fields, gardens, courtyards, and dining areas; the standard
would typically not be applied to parking lots or private streets/driveways. At the interior of a
school, an hourly-average noise level (Lq(h)) of up to 45 dB(A) is acceptable.
6 Thresholds of Significance
Based on the noise criteria discussed above, and the CEQA guidelines, a significant impact will be
assessed if the Project will result in:
® Exposure of persons to or generation of noise levels in excess of standards established in the
local general plan or noise ordinance, or applicable standards of other agencies. This impact will
occur if:
The noise levels generated by the Project exceeds 60 dB CNEL at exterior areas of off-site
residences; or,
The CNEL at exterior usable areas of the school campus exceeds 65 dB; or,
The 1-hour average noise level (Leq) exceeds 45 dB(A) inside any school building; or,
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Project construction activities occur outside the hours permitted by the City of Carlsbad
municipal code.
® A substantial permanent increase in ambient noise levels in the Project vicinity above levels
existing without the Project. This impact will occur if:
Project traffic increases the CNEL at any off-site residence by a perceptible amount of 3 dB
or more if the exterior CNEL without Project is 60 dB or less; or
Project traffic increases the CNEL at any off-site residence by any amount if the exterior
CNEL without Project exceeds 60 dB; or
Activity noise levels at the Project site increase the CNEL at any off-site residence by 3 dB or
more.
® A substantial temporary or periodic increase in ambient noise levels in the Project vicinity above
levels existing without the Project. This condition will occur if construction of the proposed
Project increases the CNEL at any off-site residence by 3 dB or more.
® Exposure of persons to, or generation of, excessive groundborne vibration or groundborne noise
levels.
® Exposure of persons residing or working in the study area to excessive noise levels as a result of
activities at McClellan-Palomar Airport.
7 Existing Noise Environment
The nearest sensitive receptors to the Project site are:
® Existing single family homes to the south. These homes are located approximately 15 to 20 feet
below the grade of the Project site. The distance between the property line of the closest home
and the top-of-slope at the Project site is approximately 50 feet.
® Existing single family homes to the west. These homes are located approximately 150 feet above
the grade of the Project site. The distance between the property line of the closest homes and
the school site is approximately 450 feet.
Immediately north of the Project site is an existing RV storage facility and immediately east of the
project site is El Fuerte Street. Further to the north and east are other existing streets (Bressi Ranch
Way and Gateway Road) and undeveloped land. Existing sources of noise that currently affect the
study area are traffic, aircraft operations at McClellan-Palomar Airport and activities at the existing
PRS campus.
7.1 Noise Measurements
In order to document the existing noise environment, measurements were obtained at four
locations throughout the study area. (Refer to Figure 7-1.) At three of the locations, continuous 24-
hour noise measurements were obtained. At the remaining location, the measurement was
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Community Development. Figure 4-2 indicates the typical outdoor CNEL at various locations for
typical noise sources.
5 Noise Criteria
The following sections discuss the various noise criteria that have been considered for this study.
5.1 State of California Office of Planning and Research
The State Office of Planning and Research (OPR) Noise Element Guidelines include recommended
exterior and interior noise level standards for local jurisdictions to identify and prevent the creation
of incompatible land uses due to noise. The OPR Guidelines contain a land use compatibility table
that describes the compatibility of different land uses with a range of environmental noise levels in
terms of CNEL. A noise environment of 50 to 60 dB CNEL is considered to be "normally acceptable"
for residential uses according to those Guidelines. For schools, a CNEL of 50 to 70 dB is considered to
be "normally acceptable." The OPR recommendations also note that, under certain conditions, more
restrictive standards than the maximum levels cited may be appropriate. As an example, the
standards for quiet suburban and rural communities may be reduced by 5 to 10 dB to reflect lower
existing outdoor noise levels.
5.2 California Code of Regulations
Title 5, Division 1, Chapter 13, Subchapter 1, Article 2, Section 14010 of the California Code of
Regulations specifies standards for school site selection. These standards state that the site shall not
be adjacent to a road or freeway that any site-related traffic and sound level studies have
determined will have safety problems or sound levels which adversely affect the educational
program. The regulations do not quantify an adverse sound level.
5.3 California Streets and Highways Code
Section 216 of the California Streets and Highways Code identifies noise standards that must be
achieved at a school site when an adjacent freeway is altered or expanded. These standards specify
that the noise level produced by freeway traffic cannot exceed an Leq of 52 dB(A) within the interior
of any classroom, library, multipurpose room, or space used for pupil personnel services. Although
applicable to freeways, the standards are routinely applied to State highways and major arterials.
5.4 City of Carlsbad Municipal Code
The City's Municipal Code controls construction noise by limiting the hours during which activities
can occur. Specifically, Section 8.48.010 of the code states that construction may not occur:
® Before 7 a.m. or after sunset Monday through Friday; or
® Before 8 a.m. or after sunset on Saturday; or
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Table 7-1. Summary of Ambient Noise Measurements
CNEL tLocation # Location Description Average Noise Level, L,.l
On school site at approximate
1 location of future icon/arts N/A 63.0 dB(A)
building adjacent to El Fuerte.
Rear yard of 2779 Palmetto Drive, Daytime: 48.9-52.9 dB(A)
2 adjacent to EL Fuerte. 51.1 dB Evening: 44.4-49.7 dB(A)
Nighttime: 35.6-46.7 dB(A)
Rear yard of 2736 Palmetto Drive, Daytime: 40.7-52.7 dB(A)
3 south of Project site. 50.2 dB Evening: 39.2-53.1 dB(A)
Nighttime: 34.5-48.2 dB(A)
Rear yard of 6316 Montecito Drive, Daytime: 45.8-48.4 dB(A)
on bluff west of Project site. 48.3 dB Evening: 41.2-45.4 dB(A)
Nighttime: 31.9-45.9 dB(A)
Notes:
1. For 24-hour measurements the range of hourly values are provided. Daytime hours are 7 a.m. to 7
p.m. Evening hours are 7 p.m. to 10 p.m. Nighttime hours are 10 p.m. to 7a.m.
7.2 Traffic
In order to estimate existing noise levels due to traffic on El Fuerte Street, a computer noise model
was constructed using SoundPLAN software. This software implements the Federal Highway
Administration's traffic noise model (TNM; 1998) and calculates noise levels based on traffic
volumes, speeds, truck mix, site conditions, and distance from the roadway to the receptor. Table 7-
2 summarizes the traffic data used in the model. The results of the modeling effort, calibrated to the
noise measurements discussed in Section 7.1, indicate that existing traffic noise levels are up to 64
dB CNEL at the school site, and up to 55 dB CNEL at the homes to the south of the Project. Traffic
noise model outputs are provided in Appendix II.
Table 7-2. Summary of ExistiAg Traffic Data
Traffic Parameter
Roadway Type
Value
Collector a
Roadway Configuration 4 lanes, divided
Average Daily Traffic Volume (ADT), 2006 4,100b
Average Daily Traffic Volume (ADT), 2010 6,000 b
Interpolated Existing ADT, 2008 5,050
Speed Limit 35 mph a
% Medium Trucks 1.84% C
% Heavy Trucks 0.74% C
Notes:
Data obtained from San Diego Association of Governments (SANDAG) website:
http://maximus.sandag.org/tficsr11/tfic30.html
Data obtained from SANDAG website:
http: / /www.sandag.org/resources/demographics_and_other_data/transportation/adtv/carlsbad_adt.pdf
Estimated based on truck mix data for typical arterials published by the County of Orange
7.3 McClellan-Palomar Airport
Operations at McClellan-Palomar Airport, located west of the Project site, include both private
aviation and scheduled airline flights. The airport is served by a single 4,600 foot long east-west
runway. Referring to Figure 7-2, the Project site is located well outside the 60 dB CNEL noise contour
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RI
RI
((I
09
ci' RUPIWOY i , , I y
- -
- 7 Site
C~7
----------- 60 dB CNEL
Contour j
:n mow
09, PS
AIRPORT INFLUENCE AREA AIA)
$\ NTH 200 FUTURE CONDITION
NOISE EXPOSURE MAP
Ii '- I ________ -,Ia .,, •r0 150 c,*cicoov us I 31505 riO
(O PM iF PROJ NO 2,an3ao3olo, 10.1
Figure 7-2. McClellan-Palomar Airport Noise Contours and Relative Location of Project Site
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from McClellan-Palomar Airport. However, observations at the Project site indicate that noise from
aircraft overflights is audible in the study area.
8 Future Noise Environment
For ease of presentation, the discussion of future conditions in the study area with the Project has
been divided into two sections: construction and operation. Each is discussed in greater detail in the
following sections. As discussed in Section 2, the exact timing of the phases is yet to be determined,
with elements of the Project subject to the availability of funds. Different elements of the proposed
Project have the potential to either increase or decrease noise levels. For example, commissioning
of the gymnasium (which is dependent on future funding) may help reduce noise levels within the
surrounding community by moving some noise-generating activities from the exterior sports field to
inside a building, whereas parking lot noise will likely continue to increase until completion of the
master plan campus when the school reaches its full enrollment capacity. Therefore, to make an
analysis possible, assumptions have been made to represent the worst-case conditions that will
occur throughout the development process. By analyzing the worst-case conditions for each of the
major noise sources associated with the Project, the assessment of impacts may be considered a
conservative analysis that covers all the development phases.
8.1 Project Construction
In compliancewith City Code requirements, construction of the Project will occur only between 7:00
a.m. and sunset on Monday through Friday and between 8:00 a.m. and sunset on Saturday. There
will be no construction activities on Sundays or legal holidays (New Year's Day, Memorial Day,
Independence Day, Labor Day, Veterans Day, Thanksgiving Day and Christmas Day).
Construction noise levels in the vicinity of the Project will fluctuate depending on the particular
type, number and duration of use of various pieces of construction equipment. The exposure of
persons to the periodic increase in noise levels will be short-term. Table 8-1 shows typical noise
levels associated with various types of construction-related machinery.
Referring to Table 8-1, one of the noisiest pieces of construction equipment to be used at the
Project site is a grader, which is expected to produce a maximum noise level of 85 dB(A) at a
distance of 50 feet. Due to the need for grading activities at the proposed sports field, it is assumed
that this is also the equipment item that will be used closest to the nearest sensitive receptors (i.e.,
the homes to the south). This assumption, along with an assumed usage factor of 40% [41 and an 8-
hour work day, was used to develop a computer noise model using SoundPLAN software. This model
takes a number of significant variables into account, including the distance to the receptors, ground
conditions between the noise source and the receptor, and barrier effects that will be provided by
buildings or terrain. Based on this modeling the construction noise level will be up to 59.5 dB CNEL
at the closest homes south of the Project site and up to 48.5 dB CNEL at the closest homes on the
hill west of the Project site. (Construction noise model outputs are provided in Appendix Ill.)
Referring to Table 7-1, the existing noise levels at these locations are 50.2 and 48.3 dB CNEL,
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respectively. Therefore, construction will increase the ambient noise level by 3 dB or more at the
homes, producing a significant temporary impact. -
Table 8-1. Construction Noise Levels
Equipment Type or
Activity
Backhoe
Typical Maximum Noise Level
at 50 ft. in dB(A)
80
Concrete Mixer 80
Crane 85
Dozer 85
Excavator 85
Grader 85
Compactor 83
Generator 82
Saws 85
Truck (18 wheeL flatbed) 84
Truck (2,500 gallon water) 85
Truck (concrete pump) 82
Truck (concrete transport) 85
Vibrator 83
Welder 74
Source: Federal Highway Administration's Roadway Construction
Noise Model Version 1.0. February 2, 2006
On the PRS campus itself, construction noise will be clearly audible and will, at times, result in hourly
average noise levels (L) of greater than 45 dB(A) at interior locations. This is particularly true when
heavy construction machinery is used within about 550 feet of classroom buildings. However, the
impact is not considered significant because of the short duration of the activity, and because the
campus administration will have the authority to stop the construction during classroom hours if the
noise is affecting educational activities.
Groundborne vibration is measured in terms of the velocity of the vibration oscillations. As with
noise, a logarithmic decibel scale (VdB) is used to quantify vibration intensity. When groundborne
vibration exceeds 72 to 80 VdB, it is usually perceived as annoying to occupants of residential
buildings. For institutional land uses, the threshold is 75 to 83 VdB. The degree of annoyance is
dependent upon individual sensitivity to vibration and the rate of recurrence of the vibration events.
Typically, vibration levels must exceed 100 VdB before building damage occurs.
The primary vibratory source during the construction of the Project will be large bulldozers. Based
on published data 151, typical bulldozer activities generate an approximate vibration level of 87 VdB
at a distance of 25 feet. At the distance of the nearest residence to the Project site (about 90 feet to
the south) the estimated vibration level will be 70 VdB; at the residences to the west of the Project
site (about 450 feet away) the estimated vibration level will be 49 VdB. These vibration levels are
below the threshold at which building damage occurs, and below the annoyance criterion of 72 VdB
for residential buildings; therefore, the impact is not significant.
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On the PRS campus itself, it is possible that vibration will be perceived by occupants of the existing
buildings if bulldozers or other heavy equipment operate within about 35 to 65 feet of them.
However, the impact is not considered significant because of the short duration of the activity,
because the vibration levels are well below the threshold of building damage, and because the
campus administration will have the authority to stop the construction during classroom hours if the
vibration is affecting educational activities.
8.2 Project Operation
The two main types of noise sources associated with the operation of the Project are traffic and on-
campus activities. These are discussed in the following sections.
8.2.1 Traffic
The primary roadway affected by Project-related traffic will be El Fuerte Street. In order to estimate
future (2030) noise levels due to traffic on El Fuerte, computer noise models were constructed using
SoundPLAN software for both the future-without- and future-with-Project conditions. This software
implements the Federal Highway Administration's traffic noise model (TNM; 1998) and calculates
noise levels based on traffic volumes, speeds, truck mix, site conditions, and distance from the
roadway to the receptor. Table 8-2 summarizes the traffic data used in the model.
Table 8-2. Summary of Future Traffic Data
_I_________
Roadway Type Collector a
Roadway Configuration 4 lanes, divided
ADT, 2030, With Project 9,600 b
Project Generated ADT 743
North/South Split for Project Generated ADT 50%/50% b
ADT, 2030, Without Project 9,229
Speed Limit 35 mph a
% Medium Trucks 1.84% C
% Heavy Trucks 0.74% C
Notes:
Data obtained from San Diego Association of Governments (SANDAG) website:
http://maximus.sandag.org/tficsrl1/tfic30.html
Obtained from traffic engineer's Traffic Analysis Update Letter (101.
Estimated based on truck mix data for typical arterials published by the County of Orange
The results of the modeling effort indicate that future traffic noise levels at the homes to the south
of the Project site are up to 57.5 dB CNEL without the Project and up to 58 dB CNEL with the Project.
(Traffic noise model outputs are provided in Appendix II.) The 0.5 dB increase in traffic noise due to
the Project is less than significant because the overall noise exposure at the homes will remain
below 60 dB CNEL.
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8.2.2 On-Site Noise Sources
The primary on-site noise sources that will affect the homes in the vicinity of the PRS campus are
activities that occur outside the school buildings. In order to assess potential impacts with respect to
the thresholds of significance for this study (i.e., the 24-hour CNEL metric), it was necessary to
analyze a full day of activity at the Project site. An operational scenario was developed based on
information provided by school staff, the Project planner, and the Project traffic engineer. The
following points summarize the operational scenario used in the analysis:
® At the parking lot, the morning peak hour of activity will occur between 7 a.m. and 8 a.m. as
students are dropped off at school; during this hour, 113 vehicles will enter the parking lot and
60 vehicles will leave.
® At the parking lot, the afternoon peak hour of activity will occur between 3 p.m. and 4 p.m. as
students are picked up from school; during this hour, 28 vehicles will enter the parking lot and
44 vehicles will leave.
® At the parking lot, throughout the remainder of the day, there will be 498 additional trips to or
from the school. It has been assumed that these will be evenly spread throughout the remaining
daytime and evening hours (i.e., 8 a.m. to 3 p.m., and 4 p.m. to 10 p.m.). It is noted that parking
lot activities were included in the evening hours to represent attendance at sporting events (see
below) or community activities (meetings, adult education classes, etc.) that may utilize Project
buildings during the evenings.
® Mechanical equipment (air conditioners, etc.) will operate at the school buildings from 7 a.m. to
8 p.m. and will operate 50% of the time between 8 p.m. and 10 p.m.
® To account for noise generated by students during lunch break it was assumed that all 540
students will spend 30 minutes outside, during which time the primary noise will be students
talking.
® Physical education classes will take place at the sports field from 10 a.m. to 2 p.m.
® School sporting events (team practices, soccer matches, lacrosse matches, etc.) will take place at
the sports field from 3:30 p.m. to 6 p.m.
® Community sporting events will take place at the sports field from 6:30 p.m. to 8 p.m.
® No outside activities will occur at the Project site before 7 a.m. or after 10 p.m.
® With the exception of parking lot use related to activities occurring within the school buildings,
no outside activities will occur at the Project site after 8 p.m.
® Noise generated inside school buildings is not anticipated to contribute appreciably to the
overall noise exposure at nearby residences. This is based on the observations that the school
buildings are approximately 500 feet from the nearest homes and that typical classroom noise
levels are relatively low, and on the assumption that exterior doors and windows at the school
buildings will be closed during noisy events (sporting events, student gatherings, etc.)
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Based on discussions with school staff, it is our understanding that the above scenario represents
worst-case conditions at the Project site and that weekend activity levels at the site will be less than
described in this scenario.
A computer noise model was then constructed using SoundPLAN software to represent the scenario
described above. This model included all the noise sources in order to evaluate the total noise
exposure at nearby homes due to operations at the Project site. The results of the analysis indicate
that the noise levels at the closest homes to the south of the Project site will be up to 52 dB CNEL
and the noise level at the closest homes to the west of the Project site will be up to 47.5 dB CNEL.
(Operational noise model outputs are provided in Appendix IV.) These noise levels are below the
City standards of 60 dB CNEL; therefore, the impact is less than significant relative to this threshold.
Referring to Table 7-1, the existing noise levels at the homes to the south and west are 50.2 and
48.3 dB CNEL, respectively. Therefore, on-campus activities will increase the ambient noise level by
more than 3 dB at the homes to the south, producing a significant impact at this location. On-
campus activities will increase the ambient noise level by less than 3 dB at the homes to the west;
therefore, the impact is less than significant at these locations.
9 Impacts on the Project Site
9.1 Traffic Noise
The primary off-site source of noise that will affect the Project site is traffic on El Fuerte Street.
Using the traffic noise model described in Section 8.2.1., future traffic noise contour maps were
calculated for the Project Site. These maps are illustrated in Figures 9-1 and 9-2, which provide the
unmitigated exterior noise exposure (CNEL) at first floor and second floor elevations, respectively.
Based on the noise measurement obtained adjacent to El Fuerte, it is estimated that the 1-hour
average noise level (Leq) during the peak noise hour for the street is 2 dB higher than the CNEL level
(i.e., the 1-hour average noise level at the Project site can be estimated by adding 2 dB to the values
shown in Figures 9-1 and 9-2).
Referring to Figure 9-1, the estimated future noise exposure at exterior areas of the Project site is up
to 67 dB CNEL. This is a potentially significant impact; specifically, a significant impact will occur if
useable outdoor spaces are located in areas with a CNEL in excess of 65 dB.
Referring to Figure 9-2, and adding the 2 dB correction (described above), the peak 1-hour L at the
closest building to the street (the future Arts Building) is up to 68 dB(A). Assuming standard
construction techniques for permanent school buildings (with windows and doors closed) provide 20
dB of noise reduction, the interior peak 1-hour Leq at the building will be up to 48 dB(A), which
exceeds the City's standards for school buildings. Therefore, this is a significant impact. At the
remaining buildings, the exterior peak 1-hour L will be 57 dB(A) or less. Assuming mobile
classrooms and permanent school buildings provide minimum noise reductions of 15 dB and 20 dB,
respectively (with windows and doors closed), the noise levels within the remaining school buildings
will be below 45 dB(A). However, as noted previously, one of PRS's goals is to include a number of
green building technologies, such as passive heating and cooling, in the permanent school buildings.
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It is possible that buildings constructed with such design elements may provide less noise reduction
than standard construction (for example if there are additional ventilation openings for passive
airflow). Therefore the impact is potentially significant at the remaining buildings (beyond the future
Arts Building).
9.2 McClellan-Palomar Airport
Referring to Figure 7-2, the Project site is located well outside the 60 dB CNEL noise contour from
McClellan-Palomar Airport. Therefore, the impact of aircraft noise on students and staff at the
Project site is less than significant. It is noted that, based on observations at the Project site, noise
from aircraft overflights will be audible at the Project site.
10 Assessment of Impact
Using the criteria established in this study, the following may be concluded regarding the impact of
the proposed Project:
® The Project will expose persons to noise levels in excess of standards established in the local
general plan or noise ordinance, or applicable standards of other agencies. This significant
impact will occur within the future Arts Building at the Project site due to traffic noise from El
Fuerte Street. A potentially significant impact may occur within other school buildings,
depending on the final architectural designs and the possible inclusion of green building
technologies. A significant impact may also occur at usable exterior areas of the campus near El
Fuerte Street.
® The Project will produce a substantial permanent increase in ambient noise levels in the Project
vicinity above levels existing without the Project. This significant impact will occur at the homes
to the south of the Project site due to on-campus activities.
® Construction of the Project will produce a substantial temporary or periodic increase in ambient
noise levels in the Project vicinity above levels existing without the Project. This significant
impact will occur at the homes to the south and west of the Project site.
® The Project will not generate excessive groundborne vibration or groundborne noise levels.
Therefore, the impact is not significant.
® The Project will not result in the exposure of persons residing or working in the study area to
excessive noise levels as a result of activities at McClellan-Palomar Airport. Therefore, the
impact is not significant.
11 Mitigation Measures
The following sections provide measures that shall be considered in the Project's design in order to
mitigate the significant impacts.
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11.1 Mitigation of Significant Impacts Due to Project Operations
A sound barrier shall be constructed along the south end of the sports field as illustrated in
Figure 11-1. The barrier shall have a minimum height of 6 feet relative to the top-of-slope
elevation at the field. The noise barrier shall be a continuous structure without gaps or gates,
and shall be constructed of materials that provide a minimum surface density of 4 pounds per
square foot; such materials include block walls, stucco walls, tempered glass, Plexiglas, or any
combination of these materials. (It is noted that the minimum thickness required to achieve the
necessary 4 pounds per square foot will vary depending on the specific material selected.)
Doors and windows of school buildings shall be kept closed when noise-generating activities
(sporting events, student gatherings, etc.) are taking place inside. If non-standard construction
techniques are to be used at future school buildings, including green design features such as
passive heating and cooling, then architectural and mechanical plans shall be reviewed by a
qualified acoustical consultant in order to ensure the buildings will provide adequate noise
reduction. Any necessary acoustical upgrades (sound rated windows, wall construction details,
etc.) shall be incorporated into the final building plans prior to construction. A mechanical
engineer shall verify that the buildings, with acoustical upgrades, satisfy any applicable
ventilation requirements.
Once mechanical designs for the project have been prepared, analyses shall be performed by a
qualified acoustical consultant as necessary to verify that noise levels generated by mechanical
equipment at the Project site comply with the City noise standards. If mechanical noise levels do
not comply with the standards as designed, additional mitigation measures shall be
incorporated to provide compliance. (Typical mitigation measures include selecting quieter
equipment, adding or upgrading silencers, improving the design of mechanical penthouses,
raising the height of rooftop parapet walls, and/or installing screen walls around individual
equipment items.)
11.2 Reduction of Significant Impacts Due to Project Construction
The sound barrier recommended in Item #1, above, shall be constructed as early as possible in
the school expansion process so that it will also help to shield nearby residences from
subsequent construction noise.
S. Construction activities shall be limited to the hours and days permitted by the City of Carlsbad.
Pile driving shall not be permitted at the Project site.
All construction and demolition equipment shall be fitted with properly sized mufflers.
Noisy construction equipment items shall be located as far as practicable from the residential
properties to the south and west.
11.3 Mitigation of Significant Impacts at Exterior Project Areas
No exterior usable areas (e.g., gardens, sports fields/courts, courtyards, seating areas, dining
areas, etc.) of the PRS campus shall be located in areas with an exterior CNEL greater than 65
dB, as illustrated in Figure 9-1.
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11.4 Mitigation of Significant Impacts Within Project Buildings
Architectural plans for the future Arts Building shall be reviewed by a qualified acoustical
consultant in order to ensure the building will comply with the City's interior noise standard for
school buildings. Any necessary acoustical upgrades (sound rated windows, wall construction
details, etc.) shall be incorporated into the final building plans prior to construction.
If standard construction techniques are to be used at future school buildings, mechanical
ventilation shall be provided since the interior 1-hour Leq standard of 45 dB(A) is to be met with
windows and doors closed.
If non-standard construction techniques are to be used at future school buildings, including
green design features such as passive heating and cooling, then architectural and mechanical
plans shall be reviewed by a qualified acoustical consultant in order to ensure the building will
comply with the City's interior noise standard for school buildings. Any necessary acoustical
upgrades (sound rated windows, wall construction details, etc.) shall be incorporated into the
final building plans prior to construction. A mechanical engineer shall verify that the buildings,
with acoustical upgrades, satisfy any applicable ventilation requirements.
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12 Impacts after Mitigation
The proper implementation of the mitigation measures provided in Section 11 will mitigate
significant impacts due to Project operations. They will also help to reduce construction noise levels.
However, some impacts related to construction noise will remain, even after mitigation. These
significant unavoidable impacts are a result of temporary increases of 3 dB or more in the ambient
noise level at nearby residential properties during project construction.
It is not considered practical or feasible to mitigate these impacts to a less than significant level.
However, the noise may be considered acceptable because the construction will occur within in the
time periods permitted by the City of Carlsbad and because the City does not specify construction
noise limits.
13 Project Alternative
Only the "No Project" alternative has been considered in this study. Under this alternative, the
status quo would be maintained and the proposed Project would not be built. However,
development in the area would continue in accordance with the City's General Plan and zoning map.
Traffic volumes on the streets, and hence traffic noise levels, would increase as the area grows, as
discussed in Section 8.2.1 regarding future-without-Project traffic noise levels. New noise sources
associated with the Project would not be introduced into the study area.
14 References
McClellan-Palomar Airport FAR Part 150 Noise Study Update, Noise Compatibility Program, Draft
Version 4. URS. December 9, 2005.
Series 112030 Traffic Volume Forecast - http://maximus.sandag.org/tficsr11/tfic30.html. San
Diego Association of Governments (SANDAG). February 2008 Update.
City of Carlsbad Average Weekday Traffic Volumes -
http://www.sandag.org/resources/demographics and other data/transportation/adtv/carlsba
d adt.pdf. SANDAG.
FHWA Roadway Construction Noise Mode! (RCNM), Version 1.0. Federal Highway
Administration. February 2, 2006.
Transit Noise and Vibration Impact Assessment. U.S. Department of Transportation/Federal
Transit Administration (FTA-VA-90-1003-06). May 2006.
Pacific Ridge School, Bressi Ranch, Planning Area 13, Parcels 2 and 3, Conditional Use Permit -
CUP-06-11. Project Design Consultants. July 31, 2006.
"FUTURE BUILDINGS.dxf', "LEVEL 1 FOOTPRlNTS.dxf', and "PRS-EXTO.dxf' - 3-D CAD files
showing study area topography and Project building footprints. Hofman Planning & Engineering.
Provided June 17, 2008. -
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"PRS-PRPN.pdf' - plan of existing and proposed site development and surrounding topography.
Pacific Ridge School, Bressi Ranch, Carlsbad, CA - Site Plans (Phase 1 South; Phase 1 North;
Phase 2 South; Phase 2 North; and Campus Master Plan). Carrier Johnson + Culture. June 20,
2008.
Pacific Ridge School! Bressi Ranch Planning Area 13) TIA-CUP 06-11 - Traffic Analysis Update
Letter. RBF Consulting. June 27, 2008.
Preliminary Review, Pacific Ridge School - Project description narrative. Provided by Hofman
Planning & Engineering. April 16, 2008.
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APPENDIX I
Noise Measurements
75
70
5.65
45
Table 1- 1. Noise Survey
Project: Pacific Ridge School Expansion
Position: #1 - On school site, at approximate Location
of future icon/arts building
Date: June 16, 2008
Time: Noted
Noise Source: Ambient traffic and aircraft
Distance: Vanes
SLM Height: 5•
LD 820 S/N: 0996
LD CAL200
Calibrator S/N: 2916
Operator: Jonathan Higginson
I I
- - - - - - --- -
- - - -
- - - - - - - - - - - - - - -
40
35
0 20 40 60 80 100
Percent of Time Noise Level is Exceeded
Measurement Period
5:27 PM
to
2:47 PM
to to
Ln Ln Ln
2 71.6
8 69.1
25 63.1
50 51.9
90 40.3
99 38.6
Leq 63.0
Lmax 75.6
Lmin 37.7
* Leq is the average sound level during the measurement period.
Ln is the sound level exceeded n% of the time during the measurement period.
Lmax and Lmin are the maximum and minimum sound levels during the measurement period.
WIELAND ACOUSTICS, INC.
50
40
0
30
1::
Table 1-2. Measured Community Noise Equivalent Level, CNEL
Project: Pacific Ridge School Expansion
Location: #2 - Rear Yard, 2779 Palmetto Drive - Adjacent to El Fuerte Street
Date: June 16-17, 2008
Measurement Period
Hourly Noise
Level, dB(A)
-. -
MeasurementPerlod
Hourly Noise
Level, dB(A)
12:00 am- 1:00 am 37.6 12:00pm- 1:00 pm 52.9
1:00 am - 2:00 am 35.6 1:00 pm - 2:00 pm 51.9
2:00 am - 3:00 am 36.9 2:00 pm - 3:00 pm 50.9
3:00 am - 4:00 am 37.1 3:00 pm - 4:00 pm 49.4
4:00 am - 5:00 am 36.8 4:00 pm - 5:00 pm 52.1
5:00 am - 6:00 am 42.4 5:00 pm - 6:00 pm 50.9
6:00 am - 7:00 am 46.7 6:00 pm - 7:00 pm- 50.1
7:00 am - 8:00 am 50.6 7:00 pm - 8:00 pm 47.5
8:00 am - 9:00 am 50.0 8:00 pm - 9:00 pm 49.7
9:00 am - 10:00 am 49.0 9:00 pm - 10:00 pm 44.4
10:00 am -11:00 am 48.9 10:00 pm - 11:00 pm 41.5
11:00am - 12:00 pm 49.2 11:00 pm - 12:00am 41.2
CNEL: 51.1
60
I I I I I I I I I I I I I I I I I I
I IL
L - - - -- - - - J L
10
0
Time of Day
WIELAND ACOUSTICS, INC.
Table 1-3. Measured Community Noise Equivalent Level, CNEL
Project: Pacific Ridge School Expansion
Location: #3 - Rear Yard, 2736 Palmetto. Drive
Date: June 16-17, 2008
Measurement Period
Hourly Noise
Level, dB(A). . MeasürémeñtPèrlód
Hourly Noise
Level, .dB(A)
12:00 am - 1:00 am 34.9 12:00 pm- 1:00 pm 49.6
1:00 am - 2:00am 34.5 1:00 pm - 2:00 pm 48.8
2:00 am - 3:00 am 34.9 2:00 pm - 3:00 pm 44.1
3:00 am - 4:00 am 34.8 . 3:00pm - 4:00 pm 43.5
4:00 am - 5:00 am 34.6 4:00 pm- 5:00 pm 50.4
5:00am - 6:00 am 39.8 5:00 pm - 6:00 pm 48.9
6:00 am - 7:00 am 48.2 6:00 pm - 7:00 pm 49.4
7:00 am - 8:00 am 40.7 7:00 pm - 8:00 pm 53.1
8:00 am - 9:00 am 52.7 8:00 pm - 9:00 pm 45.4
9:00 am - 10:00 am 45.8 9:00 pm - 10:00 pm 39.2
10:00am -11:00 am 44.9 10:00pm - 11:00 pm 35.6
11:00 am - 12:00pm . 44.6 11:00pm - 12:00 am 35.2
CNEL: 50.2
60
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 I
50
.40
30
1::
10
0
. I.'. %. 0• •\ 'b ,
Time of Day
WIELAND ACOUSTICS, INC.
50
Table 1-4. Measured Community Noise Equivalent Level, CNEL
Project: Pacific Ridge School Expansion
Location: #4 - Rear Yard, 6316 Montecito Drive
Date: June 16-17, 2008
Measurement Period
Hourly N oise
Level, dB(A) :
.
Measurement Period
is Hourly Noe
Level, dB(A)
12:00am- 1:00 am 36.1 12:00pm- 1:00 pm 47.9
1:00am - 2:00am 32.3 1:00pm - 2:00 pm 48.2
2:00 am - 3:00 am 32.7 2:00 pm - 3:00 pm 46.8
3:00 am - 4:00 am 31.9 3:00 pm - 4:00 pm . 47.8
4:00 am - 5:00 am 34.2 4:00 pm - 5:00 pm 48.0
5:00 am - 6:00 am 38.0 5:00 pm - 6:00 pm 45.8
6:00am - 7:00 am 45.9 6:00 pm - 7:00 pm 47.4
7:00 am - 8:00 am 47.6 7:00 pm - 8:00 pm 45.4
8:00 am - 9:00 am 45.9 8:00 pm - 9:00 pm 44.3
9:00 am - 10:00 am 47.9 9:00 pm - 10:00 pm 41.2
10:00am -11:00 am 47.5 10:00 pm - 11:00 pm 38.5
11:00 am - 12:00pm 48.4 11:00 pm - 12:00am 37.9
CNEL: 48.3
60
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 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'll I'll, 11-11, .......... ............
10
0
. '. I\•. fl) b• ,. \. %. . . . . . . ,. . \. . . . . ,'. -
Time of Day
WIELAND ACOUSTICS, INC.
APPENDIX II
Traffic Noise Modeling
APPENDIX III
Construction Noise Modeling
APPENDIX IV
Operational Noise Modeling