Agenda packet — Santa Ana City Council, May 5, 2026 (part 7 of 13)

Construction staging areas for the proposed project would potentially be located on the following properties: APNs 398-093-13, 398-092-12, and 398-207-01. The disposal site for the proposed project, if needed, will be selected by the contractor. Any environmental clearances related to the EXHIBIT 2
City Council 22 – 454 5/5/2026
Chapter 2. Project Description
Noise Study Report
Santa Ana Boulevard Grade Separation Project
2-2
disposal site will be obtained by the contractor prior to construction. The proposed project is included in the 2008 Regional Transportation Plan (RTP) and 2011 cost-constrained Federal Transportation Improvement Program (FTIP) (federal approval date of December 14, 2010) as project ID ORA082610. The project as proposed is consistent with the 2011 FTIP description.

EXHIBIT 2
City Council 22 – 455 5/5/2026
§¨¦5
§¨¦405
§¨¦5
§¨¦5
§¨¦405
UV55
UV91
UV261
UV73
UV57
UV72
UV22
UV133
UV90
UV133
UV90
UV261
UV UV72 91
UV261
UV57
UV22
Anaheim
Santa Ana
Irvine
Orange
Costa Mesa
Garden Grove
Fullerton
Tustin
Fountain Valley
Newport Beach
Westminster
Tustin Foothills
Placentia
Villa Park Villa Park
Figure 1
Regional Vicinity Map
Santa Ana Boulevard Grade Separation Project
±
Source: ESRI StreetMap
North America (2008)
0 0.5 1 2
Miles
San Bernardino
Riverside
Imperial San Diego
Orange
Los Angeles
Kern
P a c i f i c
O c e a n
K:\Irvine\GIS\Projects\AECOM\00452_11\mapdoc\Fig01_Regional_Vicinity.mxd SM, NB (09-19-11) Project Site
District: 12
County: Orange
Route: Santa Ana Boulevard
Federal Project No.: STPL 5063(136)
EXHIBIT 2
City Council 22 – 456 5/5/2026
EXHIBIT 2
City Council 22 – 457 5/5/2026
Project Location
French
Park
Logan
Park
Mabury
Park
Prentice
Park
P E Railroad
BNSF RR and Amtrak
15Th
Mcclay
Standard
Spurgeon
Elk
Oakmont
Santiago
Main
Parrie
Hardly
Grace
Breeden
Trinidad
Kilson
Obarr
8Th
6Th
Brown
Dresser
Myrtle
Mortimer
Martha
Greenwood
5Th
Penn
Eastside
Porter
11Th
Stafford
12Th
Terminal
Eastwood
Patricia
2Nd
Camile
Court
Hathaway
Dorman
9Th
10Th
Valencia
Palm
Vance
Minnie
18Th
Warren
Cedar
Concord
Custer
Wellington
Fuller
Fruit
Fairmont
19Th
Bush
20Th
21St
Catalina
Logan
16Th
3Rd
Santa Fe
Minter
Garfield Hickory
Civic Center
Bishop
Pine
Lacy
Washington
Chestnut
Walnut
Wright
French
Linwood
Poinsettia
Lyon
Orange
Cypress
Halladay
Oak
14Th
Maple
4Th
Lincoln
Mabury
Santa Ana
17Th
Grand
Mortimer
5Th
4Th
Main
1St
§¨¦5
Figure 2
Project Location Map
Santa Ana Boulevard Grade Separation Project
K:\Irvine\GIS\Projects\AECOM\00452_11\mapdoc\Fig02_Project_Location.mxd SM, NB (09-19-11)) ±
Source: ESRI StreetMap
North America (2008)
0 250 500 1,000
Feet
District: 12
County: Orange
Route: Santa Ana Boulevard
Federal Project No.: STPL 5063(136)
EXHIBIT 2
City Council 22 – 458 5/5/2026
EXHIBIT 2
City Council 22 – 459 5/5/2026

SANTIAGO ST

POINSETTIA ST

METROLINK

SANTA ANA

STATION

STAFFORD ST

CUSTER ST

LOGAN ST

WASHINGTON AVE

LINCOLN AVE

FULLER ST

TERMINAL ST
E 4TH STBREEDEN
I-5 NB
I-5 SB
I-5 SB OFF
I-5 SB ON

PHOENIX HOUSE

REHAB CENTER

FRUIT ST

EASTWOOD AVE

SANTA ANA
BLVD

GRAND AVE
APN
398-093-01 APN 398-194-21
APN
398-194-22
APN
398-194-20
APN
398-194-19
APN
398-194-18
APN
398-092-09
APN
398-092-08
APN
398-092-10
APN
398-092-11
APN
398-092-14
APN
398-092-13
APN
398-092-02
APN
398-093-08
APN
398-093-07
APN
398-093-05
398-093-06
APN
398-093-04
APN
398-194-15
APN
398-194-16
APN
398-194-17
APN
398-194-23
APN
398-194-14
APN
398-093-13
398-205
-07
APN
398-202-01
APN
398-201-11
APN
398-352-10
APN
398-204-04
APN
398-352-07
APN
398-207-01
APN
398-361-07
APN
398-208-01
APN
398-101-16
APN
398-101-15
APN
398-101-14 APN
398-101-13
APN
398-101-02
APN
398-361-01
APN
398-352-06
APN
398-342-12
APN
398-381-01
APN
398-381-04
APN
398-381-02
05 03
04 02
APN
398-381-12
APN
398-461-07
APN
398-461-19
APN
398-461-18
APN
398-361-03
APN
398-361-12
APN
398-093-03
APN
398-202-07
APN
398-202-08
APN
398-202-09
APN
398-202
-10
APN
398-205-01
APN
398-205-02
APN
398-205-03
APN
398-205-04
APN
398-205
-05
APN
398-205-09
APN
398-205-08
APN
398-381-03
APN
398-381-=13
APN
398-362
-01
APN
398-092-15
APN
398-092-12
APN
398-093-02
APN
398-342-18
Figure 3
Proposed Project Area
Santa Ana Boulevard Grade Separation Project
±
Source: ESRI World Imagery
(2010)
K:\Irvine\GIS\Projects\AECOM\00452_11\mapdoc\Fig03_Project_Area.mxd Date: 5/8/2012 26629 Legend
Parcels
Limits of Disturbance
Proposed Full Aquisition
Proposed Partial Aquisition
Temporary Construction Easement
Proposed Improvements
Detour Road
Proposed Temporary Shoofly
District: 12
County: Orange
Route Santa Ana Blvd
Federal Project No: STPL 5063 (136)
0 100 200 50
Feet
EXHIBIT 2
City Council 22 – 460 5/5/2026

EXHIBIT
2 City Council 22 – 461 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-1
Chapter 3 Fundamentals of Traffic Noise
The following is a brief discussion of fundamental traffic noise concepts. For a detailed discussion, please refer to Caltrans’ Technical Noise Supplement (TeNS) (Caltrans 2009), a technical supplement to the Protocol, which is available on the Caltrans web site (<http://www.dot.ca.gov/hq/env/noise/pub/tens_complete.pdf>).

3.1 Sound, Noise, and Acoustics
Sound can be described as the mechanical energy of a vibrating object transmitted by pressure waves through a liquid or gaseous medium (e.g., air) to a hearing organ, such as a human ear.

Noise is defined as loud, unexpected, or annoying sound.

In the science of acoustics, the fundamental model consists of a sound (or noise) source, a receiver, and the propagation path between the two. The loudness of the noise source and obstructions or atmospheric factors affecting the propagation path to the receiver determines the sound level and characteristics of the noise perceived by the receiver. The field of acoustics deals primarily with the propagation and control of sound.

3.2 Frequency
Continuous sound can be described by frequency (pitch) and amplitude (loudness). A lowfrequency sound is perceived as low in pitch. Frequency is expressed in terms of cycles per second, or hertz (Hz) (e.g., a frequency of 250 cycles per second is referred to as 250 Hz). High frequencies are sometimes more conveniently expressed in kilohertz (kHz), or thousands of Hertz. The audible frequency range for humans is generally between 20 Hz and 20,000 Hz.

3.3 Sound Pressure Levels and Decibels
The amplitude of pressure waves generated by a sound source determines the loudness of that source. Sound pressure amplitude is measured in micro-Pascals (mPa). One mPa is approximately one hundred billionth (0.00000000001) of normal atmospheric pressure. Sound pressure amplitudes for different kinds of noise environments can range from less than 100 to 100,000,000 mPa. Because of this huge range of values, sound is rarely expressed in terms of mPa. Instead, a logarithmic scale is used to describe sound pressure level (SPL) in terms of decibels (dB). The threshold of hearing for young people is about 0 dB, which corresponds to 20 mPa.

3.4 Addition of Decibels
Because decibels are logarithmic units, SPLs cannot be added or subtracted through ordinary arithmetic. Under the decibel scale, a doubling of sound energy corresponds to a 3 dB increase.

In other words, when two identical sources are each producing sound of the same loudness, the EXHIBIT 2
City Council 22 – 462 5/5/2026
Chapter 3. Fundamentals of Traffic Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-2
resulting sound level at a given distance would be 3 dB higher than one source under the same conditions. For example, if one automobile produces an SPL of 70 dB when it passes an observer, two cars passing simultaneously would not produce 140 dB—rather, they would combine to produce 73 dB. Under the decibel scale, three sources of equal loudness together produce a sound level 5 dB louder than one source.

3.5 A-Weighted Decibels
The decibel scale alone does not adequately characterize how humans perceive noise. The dominant frequencies of a sound have a substantial effect on the human response to that sound.

Although the intensity (energy per unit area) of the sound is a purely physical quantity, the loudness or human response is determined by the characteristics of the human ear.

Human hearing is limited in the range of audible frequencies as well as in the way it perceives the SPL in that range. In general, people are most sensitive to the frequency range of 1,000– 8,000 Hz and perceive sounds within that range better than sounds of the same amplitude in higher or lower frequencies. To approximate the response of the human ear, sound levels of individual frequency bands are weighted, depending on human sensitivity to those frequencies.

Then, an A-weighted sound level (expressed in units of dBA) can be computed based on this information.

The A-weighting network approximates the frequency response of the average young ear when listening to most ordinary sounds. When people make judgments regarding the relative loudness or annoyance of a sound, their judgments correlate well with the A-scale sound levels of those sounds. Other weighting networks have been devised to address high noise levels or other special problems (e.g., B, C, and D scales), but these scales are rarely used in conjunction with highway traffic noise. Noise levels for traffic noise reports are typically reported in terms of dBA.

Table 3-1 describes typical A-weighted noise levels for various noise sources.

3.6 Human Response to Changes in Noise Levels
As discussed above, doubling sound energy results in a 3 dB increase in sound. However, given a sound level change measured with precise instrumentation, the subjective human perception of a doubling of loudness will usually be different from what is measured.

Under controlled conditions in an acoustical laboratory, the trained healthy human ear is able to discern 1 dB changes in sound levels when exposed to steady single-frequency (pure-tone) signals in the midfrequency (1,000 Hz–8,000 Hz) range. In typical noisy environments, changes in noise of 1 to 2 dB are generally not perceptible. However, it is widely accepted that people are able to begin to detect sound level increases of 3 dB in typical noisy environments. Further, a 5 dB increase is generally perceived as a distinctly noticeable increase, and a 10 dB increase is generally perceived as a doubling of loudness. Therefore, a doubling of sound energy (e.g., doubling the volume of traffic on a highway), which would result in a 3 dB increase in sound, would generally be perceived as barely detectable.

EXHIBIT 2
City Council 22 – 463 5/5/2026
Chapter 3. Fundamentals of Traffic Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-3
Table 3-1. Typical A-Weighted Noise Levels
Common Outdoor Activities Noise Level
(dBA) Common Indoor Activities
— 110 — Rock band
Jet fly-over at 1,000 feet
— 100 —
Gas lawnmower at 3 feet
— 90 —
Diesel truck at 50 feet at 50 mph Food blender at 3 feet — 80 — Garbage disposal at 3 feet
Noisy urban area, daytime
Gas lawnmower, 100 feet — 70 — Vacuum cleaner at 10 feet Commercial area Normal speech at 3 feet
Heavy traffic at 300 feet — 60 —
Large business office
Quiet urban daytime — 50 — Dishwasher (next room)
Quiet urban nighttime — 40 — Theater, large conference room (background) Quiet suburban nighttime
— 30 — Library
Quiet rural nighttime Bedroom at night, concert
— 20 —
Broadcast/recording studio
— 10 —
Lowest threshold of human hearing — 0 — Lowest threshold of human hearing Source: Caltrans 2009.

3.7 Noise Descriptors
Noise in our daily environment fluctuates over time. Various noise descriptors have been developed to describe time-varying noise levels. The noise descriptors most commonly used in traffic noise analysis are listed below.
• Equivalent Sound Level (Leq): Leq represents an average of the sound energy occurring over a specified period. In effect, Leq is the steady-state sound level containing the same acoustical energy as the time-varying sound that actually occurs during the same period. The 1-hour A-weighted equivalent sound level (Leq[h]) is the energy average of A-weighted sound levels occurring during a 1-hour period, and it is the basis for noise abatement criteria (NAC) used by Caltrans and the FHWA. • Percentile-Exceeded Sound Level (Lxx): Lxx represents the sound level exceeded for a given percentage of a specified period (e.g., L10 is the sound level exceeded 10 percent of the time, and L90 is the sound level exceeded 90 percent of the time).
• Maximum Sound Level (Lmax): Lmax is the highest instantaneous sound level measured during a specified period.

EXHIBIT 2
City Council 22 – 464 5/5/2026
Chapter 3. Fundamentals of Traffic Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-4
• Day-Night Level (Ldn): Ldn is the energy average of A-weighted sound levels occurring over a 24- hour period, with a 10 dB penalty applied to A-weighted sound levels occurring during nighttime hours between 10 p.m. and 7 a.m.
• Community Noise Equivalent Level (CNEL): Similar to Ldn, CNEL is the energy average of the Aweighted sound levels occurring over a 24-hour period, with a 10 dB penalty applied to A-weighted sound levels occurring during the nighttime hours between 10 p.m. and 7 a.m. and a 5 dB penalty applied to the A-weighted sound levels occurring during evening hours between 7 p.m. and 10 p.m.

3.8 Sound Propagation
When sound propagates over a distance, it changes in level and frequency content. The manner in which noise reduces with distance depends on the factors listed below.

3.8.1 Geometric Spreading
Sound from a localized source (i.e., a point source) propagates uniformly outward in a spherical pattern. The sound level attenuates (or decreases) at a rate of 6 dB for each doubling of distance from a point source. Highways consist of several localized noise sources on a defined path and, hence, can be treated as a line source, which approximates the effect of several point sources.

Noise from a line source propagates outward in a cylindrical pattern, often referred to as cylindrical spreading. Sound levels attenuate at a rate of 3 dB for each doubling of distance from a line source.

3.8.2 Ground Absorption
The propagation path of noise from a highway to a receiver is usually very close to the ground.

Noise attenuation from ground absorption and reflective-wave canceling adds to the attenuation associated with geometric spreading. Traditionally, the excess attenuation has also been expressed in terms of attenuation per doubling of distance. This approximation is usually sufficiently accurate for distances of less than 200 feet. For acoustically hard sites (i.e., sites with a reflective surface between the source and the receiver, such as a parking lot or body of water), no excess ground attenuation is assumed. For acoustically absorptive or soft sites (i.e., soft dirt, grass, or scattered bushes and trees), an excess ground-attenuation value of 1.5 dB per doubling of distance is normally assumed. When added to the cylindrical spreading, the excess ground attenuation results in an overall drop-off rate of 4.5 dB per doubling of distance.

3.8.3 Atmospheric Effects
Receptors located downwind from a source can be exposed to increased noise levels relative to calm conditions, whereas locations upwind can experience lowered noise levels. Sound levels can be increased at large distances from the highway (e.g., more than 500 feet) due to atmospheric temperature inversion (i.e., increasing temperature with elevation). Other factors such as air temperature, humidity, and turbulence can also have significant effects.

EXHIBIT 2
City Council 22 – 465 5/5/2026
Chapter 3. Fundamentals of Traffic Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-5

3.8.4 Shielding by Natural or Human-Made Features
A large object or barrier in the path between a noise source and a receiver can substantially attenuate noise levels at the receiver. The amount of attenuation provided by shielding depends on the size of the object and the frequency content of the noise source. Natural terrain features (e.g., hills and dense woods) and human-made features (e.g., buildings and walls) can substantially reduce noise levels. Walls are often constructed between a source and a receiver for the specific purpose of noise reduction. A barrier that breaks the line of sight between a source and a receiver will typically result in at least 5 dB of noise reduction. Taller barriers provide increased noise reduction. Vegetation between the highway and receiver is rarely effective in reducing noise because it does not create a solid barrier.

EXHIBIT 2
City Council 22 – 466 5/5/2026
Chapter 3. Fundamentals of Traffic Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
3-6
This page intentionally left blank
EXHIBIT 2
City Council 22 – 467 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
4-1
Chapter 4 Federal Regulations and State
Policies
This section focuses on the requirements of 23 CFR 772.

4.1 Federal Regulations

4.1.1 23 CFR 772
Provided in 23 CFR 772 are procedures for preparing operational and construction noise studies and evaluating noise abatement considered for federal and federal-aid highway projects. Under 23 CFR 772.7, projects are categorized as Type I, Type II or Type III projects. FHWA defines a Type I project as a proposed federal or federal-aid highway project for the construction of a highway at a new location, the physical alteration of an existing highway that significantly changes either the horizontal or vertical alignment, or an increase in the number of through traffic lanes. A Type II project is a noise barrier retrofit project that involves no changes to highway capacity or alignment. Type III projects are projects that do not meet the classifications of either a Type I or Type II project. Type III projects do not require a noise analysis.

Type I projects include those that create a completely new noise source as well as those that increase the volume or speed of traffic or move the traffic closer to a receiver. Type I projects include those that add an interchange, ramp, auxiliary lane, or truck-climbing lane to an existing highway or widen an existing ramp by a full lane width for its entire length. Projects that are unrelated to increased noise levels, such as striping, lighting, signing, and landscaping projects, are not considered Type I projects.

Under 23 CFR 772.11, noise abatement must be considered for Type I projects if the project is predicted to result in a traffic noise impact. In such cases, 23 CFR 772 requires the project sponsor to consider noise abatement before adoption of the final National Environmental Policy Act (NEPA) document. This process involves identification of noise abatement measures that are reasonable, feasible, and likely to be incorporated into the project as well as noise impacts for which no apparent solution is available.

Traffic noise impacts, as defined in 23 CFR 772.5, occur when the predicted noise level in the design year approaches or exceeds the NAC specified in 23 CFR 772, or a predicted noise level substantially exceeds the existing noise level (a substantial noise increase). However, 23 CFR 772 does not specifically define the terms approach or substantial increase; these criteria are defined in the Protocol, as described below.

Table 4-1 summarizes the NAC corresponding to various land use activity categories. Activity categories and related traffic noise impacts are determined according to actual land uses in a given area.

EXHIBIT 2
City Council 22 – 468 5/5/2026
Chapter 4. Federal Regulations and State Policies
Noise Study Report
Santa Ana Boulevard Grade Separation Project
4-2
Table 4-1. Activity Categories and Noise Abatement Criteria Activity
Category
NAC, Hourly A-Weighted
Noise Level (dBA Leq[h])1
(Evaluation Location)
Description of Activities
A 57 (Exterior) Lands on which serenity and quiet are of extraordinary significance and serve an important public need and where the preservation of those qualities is essential if the area is to continue to serve its intended purpose.

B2 67 (Exterior) Residential.

C2 Exterior 67 (Exterior) Active sport areas, amphitheaters, auditoriums, campgrounds, cemeteries, day care centers, hospitals, libraries, medical facilities, parks, picnic areas, places of worship, playgrounds, public meeting rooms, public or nonprofit institutional structures, radio studios, recording studios, recreation areas, Section 4(f) sites, schools, television studios, trails, and trail crossings.

D 52 (Interior) Auditoriums, day care centers, hospitals, libraries, medical facilities, places of worship, public meeting rooms, public or nonprofit institutional structures, radio studios, recording studios, schools, and television studios.

E 72 (Exterior) Exterior Hotels, motels, offices, restaurants/bars, and other developed lands, properties, or activities not included in A–D or F.

F n/a Agriculture, airports, bus yards, emergency services, industrial, logging, maintenance facilities, manufacturing, mining, rail yards, retail facilities, shipyards, utilities (water resources, water treatment, electrical), and warehousing.

G n/a Undeveloped lands that are not permitted.
1 The Leq(h) activity criteria values are for impact determination only and are not design standards for noise abatement measures.

All values are A-weighted decibels (dBA). 2 Includes undeveloped lands permitted for this activity category. n/a – Not applicable. There is no NAC for this activity category.

In identifying noise impacts, primary consideration is given to exterior areas with frequent human use. In situations where there are no exterior activities or where the exterior activities are far from the roadway or physically shielded in a manner that prevents an impact on exterior activities, the interior criterion (Activity Category D) is used as the basis for determining a noise impact.

4.2 State Regulations and Policies

4.2.1 Traffic Noise Analysis Protocol for New Highway Construction and Reconstruction Projects
The Protocol specifies the policies, procedures, and practices to be used by agencies that sponsor new construction or reconstruction of federal or federal-aid highway projects. The NAC specified in the Protocol are the same as those specified in 23 CFR 772. The Protocol defines a noise increase as substantial when the predicted noise levels with project implementation exceed EXHIBIT 2
City Council 22 – 469 5/5/2026
Chapter 4. Federal Regulations and State Policies
Noise Study Report
Santa Ana Boulevard Grade Separation Project
4-3
existing noise levels by 12 dBA. The Protocol also states that a sound level is considered to approach an NAC level when the sound level is within 1 dB of the NAC identified in 23 CFR 772 (e.g., 66 dBA is considered to approach the NAC of 67 dBA but 65 dBA is not).

The TeNS of the Protocol provides detailed technical guidance for the evaluation of highway traffic noise. This includes field measurement methods, noise modeling methods, and report preparation guidance.

4.2.2 Section 216 of the California Streets and Highways Code Section 216 of the California Streets and Highways Code relates to the noise effects of a proposed freeway project on public and private elementary and secondary schools. Under this code, a noise impact occurs if, as a result of a proposed freeway project, noise levels exceed 52 dBA Leq(h) in the interior of public or private elementary or secondary classrooms, libraries, multipurpose rooms, or spaces. This requirement does not replace the “approach” or “exceed” NAC criterion for FHWA Activity Category D for classroom interiors, but it is a requirement that must be addressed in addition to the requirements of 23 CFR 772.

If a project results in a noise impact under this code, noise abatement must be provided to reduce classroom noise to a level that is at or below 52 dBA Leq(h). If the noise levels generated from freeway and non-freeway sources exceed 52 dBA Leq(h) prior to the construction of the proposed freeway project, then noise abatement must be provided to reduce the noise to the level that existed prior to construction of the project.

4.2.3 City of Santa Ana
The City of Santa Ana Noise Control Section 18-314 requires that noise sources associated with construction, repair, remodeling, or grading of any real property, provided said activities do not take place between the hours of 8:00 p.m. and 7:00 a.m. on weekdays, including Saturday, or any time on Sunday or a federal holiday.

EXHIBIT 2
City Council 22 – 470 5/5/2026
Chapter 4. Federal Regulations and State Policies
Noise Study Report
Santa Ana Boulevard Grade Separation Project
4-4
This page intentionally left blank
EXHIBIT 2
City Council 22 – 471 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
5-1
Chapter 5 Study Methods and Procedures

5.1 Methods for Identifying Land Uses and Selecting Noise Measurement and Modeling Receiver Locations
A field investigation was conducted to identify land uses that could be subject to traffic and construction noise impacts from the proposed project. Land uses in the project area were categorized by land use type; Activity Category, as defined in Table 4-1; and the extent of frequent human use. Although all developed land uses are evaluated in this analysis, as stated in the Protocol, the focus of this impact analysis was on locations of frequent human use that would benefit from a lowered noise level—specifically, locations with defined outdoor activity areas.

For this project, the potentially affected noise-sensitive uses with defined outdoor activity areas consist of residential and institutional land uses.

The geometry of the project relative to nearby existing land uses was also identified, and the possibility of planned, programmed, and designed uses occurring on undeveloped land was investigated. According to City of Santa Ana planning documents, there are no planned, programmed, and designed land uses in the vicinity of the project.

Short-term measurement locations were selected to represent the noise-sensitive land uses within the project area. Additionally, one long-term measurement site was selected to capture the diurnal traffic noise level patterns in the project area. Short-term and long-term measurement locations were selected to serve as representative modeling locations. Additional nonmeasurement locations were selected as modeling locations to gain a more complete understanding of the noise environment in the project area.

5.2 Field Measurement Procedures
A field noise study was conducted in accordance with recommended procedures in TeNS. The following is a summary of the procedures that were used to collect short-term and long-term sound level data.

5.2.1 Short-Term Measurements
Short-term monitoring was conducted at four locations on January 11, 2012 using a Larson Davis Type 1 (precision grade) sound-level meter. The measurements were conducted at Activity Category B, C, and F land uses. The short-term measurement locations are identified in Figure 5-

1. During the short-term measurements, the field staff was present. The Leq values collected during each measurement period (10 minutes in duration) were automatically recorded with digital integrating sound-level meters and subsequently logged manually on field data sheets for each EXHIBIT 2
City Council 22 – 472 5/5/2026
Chapter 5. Study Methods and Procedures
Noise Study Report
Santa Ana Boulevard Grade Separation Project
5-2
measurement location. Dominant noise sources observed and other relevant measurement conditions were also identified and logged manually on the field data sheets. The calibration of the meter was checked before and after the measurement using a Larson-Davis Model CAL 200 calibrator.

Temperature, wind speed, and humidity were recorded manually during the short-term monitoring sessions using a Kestrel 3000 portable weather station. During the short-term measurements, wind speeds typically ranged from 0 to 1 mph. Temperatures ranged from 65°F to 68°F, with relative humidity ranging from 34 to 45 percent.

5.2.2 Long-Term Measurements
Long-term monitoring was conducted at one location (LT1) using a Rion Model NL-21 soundlevel meter. The purpose of the measurement was to identify the diurnal traffic noise pattern throughout the typical day/night cycle. The long-term sound level data was collected over a time period of 24 hours, beginning January 11, 2012, and ending January 12, 2012.

Long-term noise monitoring location LT1 is shown in Figure 5-1. LT1 was located in the sports and recreation area of a drug and alcohol rehabilitation center (Phoenix House) at 1207 East Fruit Street, on the southeastern end of the project area. The sound-level meter was located in the sports and recreation area of the facility, approximately 80 feet from the fence line separating the property from Santa Ana Boulevard. The site was selected in order to document the daily traffic noise pattern, with minimal influence from the rail alignment, which was located more than 800 feet away with buildings intervening. This portion of the project area was influenced by traffic noise from the nearby I-5 freeway (which is not part of this project) as well as traffic noise from Santa Ana Boulevard.

5.3 Traffic Noise Levels Prediction Methods
Traffic noise levels were predicted using FHWA Traffic Noise Model (TNM), version 2.5. TNM is a computer model based on two FHWA reports: FHWA-PD-96-009 and FHWA-PD-96-010 (FHWA 1998a; FHWA 1998b). Key inputs to the traffic noise model were the locations of roadways, shielding features (e.g., topography and buildings), noise barriers, and receivers as well as ground type. Three-dimensional representations of these inputs were developed using CAD drawings, aerials, and topographic contours provided by the project engineer.

Traffic volume data for the project was provided in December 2011 (AECOM 2011). Traffic noise was evaluated under existing conditions, Design Year (2035) No Build conditions, and Design Year (2035) Build conditions. AM traffic volumes were utilized because these were generally slightly higher than PM traffic volumes. Tables A-1 and A-2 in Appendix A summarize the traffic volumes and assumptions used for modeling the existing and design-year conditions with and without the project.

EXHIBIT 2
City Council 22 – 473 5/5/2026
!> !>!>
!>
!> !>
!>
!>
!>
!>
!>
!>
!>
!>
!>
!>
!>
Area A
Area D
Area C
Area B NB-2
NB-1
Santa Ana Blvd
Santiago St
Logan St
Lincoln Ave
Fuller St
Grand Ave
E Fruit St
§¨¦5
Santa Ana Regional
Transportation Center
ST1
ST2
ST4
ST3
LT1
M11
M10
M12 M9
M4
M5
M1 M8
M3
M2
M7
M6
BNSF RR and Amtrak
Figure 5-1
Analysis Areas, Noise Monitoring and Modeling Locations, and Locations of Evaluated Noise Barriers Santa Ana Boulevard Grade Separation Project
K:\Irvine\GIS\Projects\AECOM\00452_11\mapdoc\Noise\Fig05-1_noise_measurement_locs.mxd Date: 10/2/2012 26629 Legend
!> Short Term Location
!> Long Term Location
!> Modeled Location
Noise Barrier (NB)
Noise Analysis Area
Project Site
Railroad
SOURCE: Bing Maps Aerial
(2010)
±
0 50 100 200
Feet
EXHIBIT 2
City Council 22 – 474 5/5/2026

EXHIBIT
2 City Council 22 – 475 5/5/2026
Chapter 5. Study Methods and Procedures
Noise Study Report
Santa Ana Boulevard Grade Separation Project
5-3

5.4 Methods for Identifying Traffic Noise Impacts and Consideration of Abatement
Traffic noise impacts occur at receiver locations where predicted design-year noise levels approach or exceed the NAC for the applicable Activity Category, or where substantial noise increases above existing noise levels would occur. Where traffic noise impacts are identified, noise abatement must be considered for reasonableness and feasibility, as required by 23 CFR 772 and the Protocol.

According to the Protocol, abatement measures are considered acoustically feasible if a minimum noise reduction of 5 dB at affected receiver locations is predicted with implementation of the abatement measures. In addition, barriers should be designed to intercept the line of sight from the exhaust stack of a truck to the first tier of receivers, as required by the Caltrans Highway Design Manual, Chapter 1100 (Caltrans 2006). Other factors that affect feasibility include topography, access requirements for driveways and ramps, the presence of local cross streets, utility conflicts, other noise sources in the area, and safety considerations. The overall reasonableness of noise abatement is determined by considering factors such as cost, and the opinions of affected property owners and residents. Additionally, the barrier must provide at least 7 dB of noise reduction at one or more benefited receptors. This design goal applies to any receptor and is not limited to impacted receptors.

The Protocol defines the procedure for assessing reasonableness of noise barriers from a cost perspective. A cost-per-residence allowance is calculated for each benefited residence (i.e., residences that receive at least 5 dB of noise reduction from a noise barrier). The allowance currently is $55,000 per benefited residence. Total allowances are calculated by multiplying the cost per residence by the number of benefited residences.

EXHIBIT 2
City Council 22 – 476 5/5/2026
Chapter 5. Study Methods and Procedures
Noise Study Report
Santa Ana Boulevard Grade Separation Project
5-4
This page intentionally left blank
EXHIBIT 2
City Council 22 – 477 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-1
Chapter 6 Existing Noise Environment

6.1 Existing Land Uses
A field investigation was conducted to identify land uses that could be subject to traffic and construction noise impacts from the proposed project. Single-family residences and a drug and alcohol rehabilitation center were identified as Activity Category B and C land uses in the project area.

Although all developed land uses are evaluated in this analysis, as required by the Protocol, noise abatement was considered only for areas of frequent human use that would benefit from a lowered noise level. Accordingly, this impact analysis focuses on locations with defined outdoor activity areas, such as residential backyards and recreation areas.

6.2 Noise Measurement Results
The existing noise environment in the project area is characterized below based on the short- and long-term noise monitoring conducted.

6.2.1 Short-Term Monitoring
Table 6-1 summarizes the results of the short-term noise monitoring conducted in the project area. Table 6-1 lists the receptor name, address, land use/Activity Category, measurement start time date and duration, measured Leq, and estimated peak noise hour (using the corresponding long-term noise monitoring data).

6.2.2 Long-Term Monitoring
Long-term monitoring was conducted at one location (LT1). The purpose of the long-term noise measurement was to determine the changes in noise levels within the project area throughout a typical day. Using the difference, or offset, in the simultaneous noise levels between the shortterm and long-term data, the long-term measurement at LT1 was used to estimate existing peaknoise-hour levels at the representative short-term receivers. The long-term sound level data were collected from Wednesday, January 11, 2012, to Thursday, January 12, 2012. The long-term monitoring location is shown in Figure 5-1.
• LT1: Long-term monitoring site LT1 is located at Phoenix House Rehabilitation Center, 1207 East Fruit Street (same location as ST-1) in the southeastern portion of the project area.

The loudest-hour noise level measured was 69.2 dBA Leq(h) during the 8 p.m. – 9 p.m. hour.

Table 6-2 and Figure 6-1 summarize the results of the LT-1 data.

EXHIBIT 2
City Council 22 – 478 5/5/2026
Chapter 6. Existing Noise Environment
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-2
Table 6-1. Summary of Short-Term Measurements
Receptor Address
Land Uses/
Activity
Category
Start
Date/
Time
Duration
(minutes) Leq Lmax Lmin L90 L50 L10
PeakNoiseHour
Leq1
ST1 1207 East Fruit
Street
Phoenix
House
Rehabilitation
Center / C
1/11/12
10:04 a.m.
10:00 65.9 72.4 61.5 63.3 65.3 68 68.4
1/11/12
10:15 a.m.
10:00 67.2 74.4 63.7 65.4 66.8 68.5 69.7
ST2 926 Lincoln
Street
Residential /
B
1/11/12
11:50 a.m.
10:00 64.5 79.2 49.5 54.3 62 68 65.5
1/11/12
12:10
10:00 63.1 72.6 49.6 52.5 59.6 67.4 63.8
ST3 SE corner,
Santa Ana
Boulevard /
Santiago Street
Train
Station
Parking
Area / F
1/11/12
1:40 p.m.
10:00 70.8 83.9 57.3 62.8 67.9 74.1 73.2
1/11/12
1:50 p.m.
10:00 69.6 81.9 54.3 59.9 67 72.3 72
ST4 Adjacent to 917
Logan Street2 Residential / B
1/11/12
2:25 p.m.
10:00 66.6 75.2 48.5 56.6 63.5 70.9 69
1/11/12
2:35 p.m.
10:00 66.1 76.1 46.5 55.1 63 70.5 68.5
Note: Refer to Figure 5-1 for measurement locations. 1 Measured existing noise level, adjusted to the peak-noise-hour level using diurnal noise data from LT-1. 2 Acoustically equivalent to the rear and side yard areas.

Table 6-2. Summary of Long-Term Monitoring at Location LT-1 Date Time
(hour beginning) 1-Hour Leq (dBA) Difference from Loudest Hour (dB) January 11, 2012 11:00:00 68.2 -1.0
12:00:00 68.6 -0.6
13:00:00 66.8 -2.4
14:00:00 66.9 -2.3
15:00:00 65.9 -3.3
16:00:00 66.8 -2.4
17:00:00 65.1 -4.1
18:00:00 64.2 -5.0
19:00:00 66.0 -3.2
20:00:00 69.2 0.0
21:00:00 67.7 -1.5
22:00:00 65.8 -3.4
23:00:00 64.7 -4.5
January 12, 2012 0:00:00 63.0 -6.2
EXHIBIT 2
City Council 22 – 479 5/5/2026
Chapter 6. Existing Noise Environment
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-3
Date Time
(hour beginning) 1-Hour Leq (dBA) Difference from Loudest Hour (dB) January 12, 2012 1:00:00 62.1 -7.1
2:00:00 61.6 -7.6
3:00:00 60.4 -8.8
4:00:00 62.6 -6.6
5:00:00 66.9 -2.3
6:00:00 68.8 -0.4
7:00:00 68.7 -0.5
8:00:00 67.3 -1.9
9:00:00 66.3 -2.9
10:00:00 66.7 -2.5
Maximum 69.2
Minimum 60.4
Note: Worst-case noise hours are bolded.

Figure 6-1. Long-Term Monitoring at Location LT1, January 11-12, 2012 EXHIBIT 2
City Council 22 – 480 5/5/2026
Chapter 6. Existing Noise Environment
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-4

6.2.3 Traffic Noise Model Calibration
TNM 2.5 was used to compare measured traffic noise levels to modeled noise levels at field measurement locations using traffic count data collected at the time of the noise measurements.

Four sets of traffic counts and four measurements (ST1, ST2, ST3, and ST4) were gathered on January 11, 2012 to calibrate the TNM model.

TNM Version 2.5 was used to compare measured traffic noise levels to modeled noise levels at field measurement locations using traffic count data collected at the time of the noise measurements. Table 6-3 compares measured and modeled noise levels at each measurement location. Appropriate agreement (less than four decibels) was achieved between the measured and modeled results.

Calibration results that did not agree to the tenth of a decibel with measured noise levels were adjusted by the use of K-factors for the subsequent modeling of existing and future peak-noisehour traffic noise. Table 6-3 shows which adjustment factors were applied to each modeling receiver.

Receivers ST1, ST-2, ST3, and ST4 were found to have differences in measured versus modeled existing sound levels of -3.3, 1.6, 3.5, and 3.1 decibels, respectively. These K-factors were applied to the modeled results for ST1, ST2, ST3, and ST4, as shown in Table 6-3. Modeled existing peak-hour traffic noise levels at all modeling receivers are listed in Table 7-1.

Table 6-3. Comparison of Measured with Modeled Peak-Noise-Hour Sound Levels Measurement
Location
Measured Existing
Sound Level (dBA)
Modeled Existing
Sound Level (dBA)
Measured minus
Modeled (dBA)
ST1 65.9 69.2 -3.3
ST2 64.5 62.9 1.6
ST3 70.8 67.3 3.5
ST4 66.6 63.5 3.1

6.2.4 Existing Modeled Noise Levels
To more accurately model Santa Ana Boulevard and the surrounding area, the existing and future alignments were divided into four areas, as shown on Figure 5-1:
• Area A, north of Santa Ana Boulevard, east of Santiago Street and west of the rail alignment. • Area B, north of Santa Ana Boulevard and east of the rail alignment. • Area C, south of Santa Ana Boulevard, east of Santiago Street and west of the rail alignment. • Area D, south of Santa Ana Boulevard and east of the rail alignment.

EXHIBIT 2
City Council 22 – 481 5/5/2026
Chapter 6. Existing Noise Environment
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-5
Table 6-4 presents additional information for the measured and modeled receivers including area designation, land use/activity category, number of dwelling units or dwelling unit equivalents, address, and the K-factor used for the subsequent TNM modeling analysis.

Table 7-1 presents the existing modeled noise levels at each receiver (ST1 through ST4 and modeled-only receivers M1 through M12). As shown in Table 7-1, existing peak-noise-hour traffic noise levels range from 54.2 to 74.1 dBA Leq(h). FHWA/Caltrans NAC are currently approached or exceeded at six of the modeled receptors (ST2, M3, ST4, M4, M11, and M12), which are representative of six residential or otherwise noise-sensitive uses.

Table 6-4. Measured and Modeled Receiver Information
Receiver
I.D. Area
Land Use / Activity
Category
Number of
Dwelling
Units or
Equivalent Address
K-Factor Used
for TNM
Modeling (dBA)
M1 A Commercial Industrial / F 0 953 E. Santa Ana Blvd. 3.5 M2 A Residential / B 1 922 N. Logan St. 3.1
M3 A Residential / B 1 920 N. Logan St. 3.1
ST4 A Residential / B 1 917 N. Logan St. 3.1
M4 A Residential / B 1 917 N. Logan St. 3.1
M5 A Residential / B 1 925 N. Logan St. 3.1
ST2 A Residential / B 1 926 Lincoln St. 1.6
M9 B Commercial Industrial / F 0 1006 Fuller St. 1.6
ST3 C Transportation (Rail Station)
/ F
0 SE corner, Santa Ana
Boulevard / Santiago St.

3.5 M6 C Transportation (Rail Station)
/ F
0 1000 E. Santa Ana
Blvd.

1.6 M7 C Transportation (Rail Station)
/ F
0 1000 E. Santa Ana
Blvd.

1.6 M8 D Commercial Industrial / F 0 973 Fuller St. 1.6 M10 D Recreation / C 1 1207 East Fruit St. -3.3
M11 D Recreation / C 1 1207 East Fruit St. -3.3
ST1 D Recreation / C 1 1207 East Fruit St. -3.3
M12 D Recreation / C 1 1207 East Fruit St. -3.3
EXHIBIT 2
City Council 22 – 482 5/5/2026
Chapter 6. Existing Noise Environment
Noise Study Report
Santa Ana Boulevard Grade Separation Project
6-6
This page intentionally left blank
EXHIBIT 2
City Council 22 – 483 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-1
Chapter 7 Future Noise Environment, Impacts,
and Considered Abatement

7.1 Future Noise Environment and Impacts
Table 7-1 summarizes the traffic noise modeling results for existing conditions and Design Year (2035) Build and No Build conditions.

The results in Table 7-1 indicate that predicted traffic noise levels for the Design Year Build conditions would approach or exceed the NAC of 67 dBA Leq(h) for Activity Category B (residential) land uses at three receivers (M3, ST4 and M4). Additionally, traffic noise levels for the Design Year Build conditions would approach or exceed the NAC of 67 dBA Leq(h) for Activity Category C land uses at three receivers (M11, ST1 and M12). Modeled Design Year Build noise levels range from 55.5 dBA Leq(h) at receiver M7 to 77.5 dBA Leq(h) at receiver ST3.

Ten receivers (M1, M2, M3, ST4, M4, M5, ST2, M9, M6 and M8) would experience decreases in project noise (compared with Design Year No Build) due to the change in roadway/receptor geometry; construction of the proposed project would result in a decrease in roadway elevation relative to the adjacent receivers. The height of the retaining wall structure would provide structural shielding to receivers from future traffic noise. Nonetheless, traffic noise impacts are predicted to occur at Activity Category B and C land uses within the project area, and noise abatement must be considered.

7.2 Preliminary Noise Abatement Analysis
In accordance with 23 CFR 772, noise abatement is considered where noise impacts are predicted in areas of frequent human use that would benefit from a lowered noise level. Potential noise abatement measures identified in the Protocol include the following:
 Avoiding the impact by using design alternatives, such as altering the horizontal and vertical alignment of the project;
 Constructing noise barriers;
 Acquiring property to serve as a buffer zone;
 Using traffic management measures to regulate types of vehicles and speeds; and  Acoustically insulating public-use or nonprofit institutional structures.

EXHIBIT 2
City Council 22 – 484 5/5/2026
Chapter 7. Future Noise Environment, Impacts, and Considered Abatement Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-2
Table 7-1. Noise Levels and Noise Barrier Modeling
Noise
Barrier
No. Area
Receptor
No. Existing
Future
No
Build
Future
Build
Activity Category (NAC)Future Build Impact Type (None, or A/E) With Barrier With Barrier With Barrier With Barrier With Barrier H = 8 ft H = 10 ft H = 12 ft H = 14 ft H = 16 ft
Leq I.L.1 Leq I.L. Leq I.L. Leq I.L. Leq I.L.
n/a A M1 70.5 74.5 74.4 F (n/a) None --2 -- -- -- -- -- -- -- -- -- NB-1 M2 63.2 66.1 65.1 B (67) None 63.8 1.3 63.4 1.7 63.0* 2.1 63.2 1.9 63.2 1.9 NB-1 M3 66.7 69.3 67.6 B (67) A/E 64.1 3.5 63.3 4.3 63.0* 4.6 62.8 4.8 62.6 5.0 NB-1 ST4 70.0 71.6 67.2 B (67) A/E 64.0* 3.2 63.9 3.3 63.7 3.5 63.4 3.8 63.2 4.0 NB-1 M4 72.4 73.4 66.9 B (67) A/E 61.0* 5.9 59.9 7.0 59.2 7.7 58.6 8.3 58.0 8.9 NB-1 M5 63.8 64.5 58.1 B (67) None 57.8* 0.3 57.7 0.4 57.5 0.6 57.4 0.7 56.6 1.5 NB-1 ST2 67.2 67.9 59.7 B (67) None 57.4* 2.3 56.8 2.9 56.6 3.1 56.5 3.2 55.8 3.9 n/a B M9 67.8 68.6 65.9 F (n/a) None -- -- -- -- -- -- -- -- -- -- n/a C ST3 74.1 77.4 77.5 F (n/a) None -- -- -- -- -- -- -- -- -- -- n/a M6 58.6 61.5 61.1 F (n/a) None -- -- -- -- -- -- -- -- -- -- n/a M7 54.2 54.4 55.5 F (n/a) None -- -- -- -- -- -- -- -- -- -- n/a D M8 63.9 64.4 62.6 F (n/a) None -- -- -- -- -- -- -- -- -- -- NB-2 M10 64.8 65.2 65.3 C (67) None 62.4 2.9 61.5 3.8 61.0* 4.3 59.3 6.0 58.5 6.8 NB-2 M11 67.9 68.7 68.7 C (67) A/E 63.5 5.2 61.8 6.9 60.0* 8.7 59.1 9.6 58.3 10.4 NB-2 ST1 67.4 68.0 68.1 C (67) A/E 63.9 4.2 62.4 5.7 61.0* 7.1 59.7 8.4 58.9 9.2 NB-2 M12 68.3 69.0 69.1 C (67) A/E 63.7 5.4 61.7 7.4 60.2 8.9 60.0* 9.1 58.3 10.8 1 I.L.: Insertion Loss.
2 Either no barrier was analyzed at this location because the modeled receptor would not approach or exceed the NAC or this receptor would be removed as part of the project. 3 Numbers in bold represent noise levels that approach or exceed the NAC. 4 Underlined noise levels have been attenuated by at least 5 dBA (i.e., feasible barrier height). * Minimum height needed to break the line of sight between 11.5 foot truck stack and first row receivers. dBA Leq = equivalent continuous sound level measured in A-weighted decibels ft = feet
H = height
NAC = Noise Abatement Criteria
n/a = not applicable
EXHIBIT 2
City Council 22 – 485 5/5/2026
Chapter 7. Future Noise Environment, Impacts, and Considered Abatement Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-3
All of these abatement options have been considered. However, because of the configuration and location of the project, abatement in the form of noise barriers is the only abatement that is considered to be practical.

Each noise barrier evaluated has been evaluated for feasibility based on achievable noise reduction. For each noise barrier found to be acoustically feasible, reasonable cost allowances were calculated. Worksheets provided in Appendix B summarize the reasonable cost allowance calculations at the critical design receiver based on the allowance calculation procedure identified in the Protocol. Table 7-1 summarizes results at receiver locations for the two noise barriers (Barrier NB-1 and Barrier NB-2) that have been evaluated in detail for this project.

For any noise barrier to be considered reasonable from a cost perspective, the estimated cost of the noise barrier should be equal to or less than the total cost allowance calculated for the barrier.

The cost calculations of the acoustically feasible noise barriers were prepared by AECOM Technical Services (January 2012) and include all items appropriate and necessary for construction of the barrier, such as traffic control, drainage modification, and retaining walls.

The design of noise barriers presented in this report is preliminary and has been conducted at a level appropriate for environmental review and not for final design of the project. Preliminary information on the physical location, length, and height of noise barriers is provided in this report. If pertinent parameters change substantially during the final project design, preliminary noise barrier designs may be modified or eliminated from the final project. A final decision on the construction of the noise abatement will be made upon completion of the project design.

The following is a discussion of noise abatement considered for each evaluation area where traffic noise impacts are predicted.

7.2.1 Area A
The traffic noise modeling results in Table 7-1 indicate that traffic noise levels at residences in Area A are predicted to be in the range of 58.1 to 67.6 dBA Leq (h) in the design year. The results also indicate that the change in traffic noise between existing conditions and the Design Year Build conditions is predicted to range from -7.5 dB at receiver ST-2 to 1.9 dB at receiver M2.1 Because the predicted noise level in the design year is predicted to approach or exceed the noise abatement criterion (67 dBA Leq[h]), traffic noise impacts are predicted at residences in this area, and noise abatement must be considered. Receivers M2, M3, ST4, M4, M5 and ST2 represent a total of 6 residences in Area A. Detailed modeling analysis was conducted for a barrier located at the top of the retaining wall. The barrier evaluated is identified as Barrier NB-1 in Figure 5-1.

Barrier heights in the range of 8 to 16 feet were evaluated in 2-foot increments. Table C-1 in Appendix C summarizes the results of the barrier analysis for each receiver location in Area A.

Reasonable allowance calculation sheets for this barrier are provided in Worksheets B-1 through B-5 in Appendix B.

1 A 3.9 dB increase would occur at receiver M1, but this location is classified as Activity Category F, and therefore is not an affected noise-sensitive land use.

EXHIBIT 2
City Council 22 – 486 5/5/2026
Chapter 7. Future Noise Environment, Impacts, and Considered Abatement Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-4
Table 7-2 summarizes the calculated noise reductions and reasonable allowances for each feasible barrier height (in this case, barriers ranging from 8 feet to 16 feet in height were determined to be feasible). Table 7-3 summarizes the estimated cost to construct Barrier NB-1, by wall height. As shown in Table 7-3, the cost of NB-1 would exceed the reasonable allowance for all of the feasible barrier heights. Barrier NB-1 was estimated to cost between $77,400 and $206,400 vs. a reasonable allowance of $55,000 to $110,000. Therefore, NB-1 was found to be not reasonable to construct.

Table 7-2. Summary of Reasonableness Determination Data—Area A – Barrier NB-1 Barrier I.D. & Location: NB-1 - Top of Retaining Wall WB Lanes Predicted Sound Level without Barrier
Critical Design Receiver: M4
Design Year Noise Level, dBA Leq(h): 66.9 dBA*
Design Year Noise Level Minus Existing
Noise Level:
-5.5 dBA*
Design Year with Barrier
8-Foot
Barrier
10-Foot
Barrier
12-Foot
Barrier
14-Foot
Barrier
16-Foot
Barrier
Barrier Noise Reduction 5.9 dBA * 7.0 dBA * 7.7 dBA * 8.3 dBA * 8.9 dBA * Number of Benefited Residences 1 1 1 1 2
Reasonable Allowance Per Benefited
Residence
$55,000 $55,000 $55,000 $55,000 $55,000
Total Reasonable Allowance $55,000 $55,000 $55,000 $55,000 $110,000 * at Critical Design Receiver
Table 7-3. Noise Barrier NB-1 Cost Estimate
Noise Barrier No. NB-1
Height (feet) 6 8 10 12 14 16
Length (feet) 430 430 430 430 430 430
Area (square feet) 2,580 3,440 4,300 5,160 6,020 6,880
Unit Cost* ($/square foot) $30 $30 $30 $30 $30 $30
Cost* $ $77,400 $103,200 $129,000 $154,800 $180,600 $206,400 *Total Cost: Averages about $30 per square foot.

Type of Wall: Masonry Block
Footings: Trench, spread or pile footings are used as appropriate.

Typical Height: 6 to 16 feet, depending on specific design needs.

Aesthetic Treatment: Decorative concrete block, e.g., color split face, slumpstone, fluted is used (consistent with City’s Planning Department Requirements.)
Engineering of Plans: Typically one month.

Construction Project: Typically two months.

7.2.2 Area D
The traffic noise modeling results in Table 7-1 indicate that traffic noise levels at noise-sensitive receivers (the recreational and classroom land uses at the rehabilitation center) in Area D are predicted to be in the range of 65.3 to 69.1 dBA Leq(h) in the design year. The results also EXHIBIT 2
City Council 22 – 487 5/5/2026
Chapter 7. Future Noise Environment, Impacts, and Considered Abatement Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-5
indicate that the increase in traffic noise between existing conditions and the design year is predicted to range from 0.5 dB at receiver M10 to 0.8 dB at receivers M11 and M12.2 Because the predicted noise level in the design year is predicted to approach or exceed the noise abatement criterion (67 dBA Leq[h]), traffic noise impacts are predicted at noise-sensitive uses in this area, and noise abatement must be considered. Receivers ST1, M10, M11 and M12 represent a total of four noise-sensitive uses in Area D3. Detailed modeling analysis was conducted for a barrier located at the right-of-way. The barrier evaluated is identified as Barrier NB-2 in Figure 5-1. Barrier heights in the range of 8 to 16 feet were evaluated in 2-foot increments. Table C-2 in Appendix C summarizes the results of the barrier analysis for each receiver location in Area D.

Reasonable allowance calculation sheets for this barrier are provided in Worksheets B-6 through B-8 in Appendix B. Table 7-4 summarizes the calculated noise reductions and reasonable allowances for each feasible barrier height (in this case, barriers ranging from 12 feet to 16 feet in height were determined to be feasible4) and the estimated cost to construct Barrier NB-2, by wall height. Barrier NB-2 was estimated to cost between $147,600 and $196,800 vs. a reasonable allowance of $$220,000. As shown in Table 7-4, NB-2 would not exceed the reasonable allowance for all of the feasible barrier heights. Therefore, Barrier NB-2 was found to be reasonable to construct at heights of 12 to 16 feet.

Table 7-4. Summary of Reasonableness Determination Data and Cost Estimate—Area D – Barrier NB-2
Barrier I.D. & Location: NB-2 – Right-of-Way Wall EB Lanes Predicted Sound Level without Barrier
Critical Design Receiver: M11
Design Year Noise Level, dBA Leq(h): 67.9 dBA*
Design Year Noise Level Minus Existing
Noise Level:

0.8 dBA*
Design Year with Barrier 12-Foot Barrier 14-Foot Barrier 16-Foot Barrier Barrier Noise Reduction 8.7 dBA * 9.6 dBA * 10.4 dBA *
Number of Benefited Residences 4 4 4
Reasonable Allowance Per Benefited
Residence
$55,000 $55,000 $55,000
Total Reasonable Allowance $220,000 $220,000 $220,000
Height (feet) 12 14 16
Length (feet) 410 410 410
Area (square feet) 4,920 5,740 6,560
Unit Cost** ($/square foot) $30 $30 $30
Cost* $ $147,600 $172,200 $196,800
Reasonable Yes/No Yes Yes Yes
Note: * at Critical Design Receiver
**Total Cost: Averages about $30 per square foot.

Type of Wall: Masonry Block
Footings: Trench, spread or pile footings are used as appropriate.

Typical Height: 6 to 16 feet, depending on specific design needs.

Aesthetic Treatment: Decorative concrete block, e.g., color split face, slumpstone, fluted is used (consistent with City’s Planning

2 A 1 dB decrease would occur at receiver M8, but this location is classified as Activity Category F, and therefore is not affected.
3 The number of sensitive receivers was determined based on the frontage length of 400 feet along Santa Ana Boulevard.
4 Barrier heights of less than 12 feet would not be feasible because they would not break the line-of-sight between the modeled receiver and an 11.5 foot high truck exhaust stack.

EXHIBIT 2
City Council 22 – 488 5/5/2026
Chapter 7. Future Noise Environment, Impacts, and Considered Abatement Noise Study Report
Santa Ana Boulevard Grade Separation Project
7-6
Department Requirements.)
Engineering of Plans: Typically one month.

Construction Project: Typically two months.

7.2.3 Nonacoustical Factors Relating to Feasibility
Factors not relating to acoustics that must be considered during the construction of noise barriers include: Safety, Maintenance, Security, and Utility Relocations. Additional factors to consider include opinions of affected residents, and input from the public and public agencies. Social, economic, legal, and technological factors also must be taken into consideration. • Geometric Standards. The presence of Barrier NB-2 would introduce potential sight distance issues for eastbound traffic traveling on Santa Ana Boulevard. The minimum horizontal stopping sight distance for 45 miles per hour (mph) is 360 feet, which cannot be provided due to the 652 feet radius curve of the centerline of Santa Ana Boulevard. • Safety. The considered noise barriers would constitute a rigid fixed object behind the sidewalk for both Barriers NB-1 and NB-2, as the leading edge for both walls would be exposed to oncoming traffic in both directions along Santa Ana Boulevard. The vehicles could jump over the curb and impact the wall head on.
• Maintenance. Both noise barriers would have a high probability of vandalism, which would then require more maintenance. Access to private property would not be required for future maintenance because the proposed sound wall is located along the right-of-way of Santa Ana Boulevard.
• Security. The proposed noise barrier does propose a potential security risk if there is a space between the wall and the existing chain link fence.
• Utility Relocations. The noise barriers would require no special utility relocation and would not cross or interfere with any existing or planned utilities.

7.2.4 Preliminary Recommendation and Decision
As shown in Sections 7.2.1 and 7.2.2, NB-1 was found to be not reasonable to construct and NB-2 was found to be reasonable to construct at heights of 12 to 16 feet.. This is the preliminary noise abatement decision.

The preliminary noise abatement decision presented in this report is based on preliminary project alignments and profiles, which may be subject to change. As such, the physical characteristics of noise abatement described herein also may be subject to change. If pertinent parameters change substantially during the final project design, the preliminary noise abatement decision may be changed or eliminated from the final project design. A final decision to construct noise abatement will be made upon completion of the project design. The preliminary noise abatement decision presented here will be included in the draft environmental document, which will be circulated for public review.

EXHIBIT 2
City Council 22 – 489 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
8-1
Chapter 8 Construction Noise
Two types of short-term noise impacts would occur during project construction. The first type would be from construction crew commutes and the transport of construction equipment and materials to the project site and would incrementally raise noise levels on access roads leading to the site. The pieces of heavy equipment for grading and construction activities would be moved on site, would remain for the duration of each construction phase, and would not add to the daily traffic volume in the project vicinity. A high single-event noise exposure potential at a maximum level of 87 dBA Lmax from trucks passing at 50 feet would exist. However, the projected construction traffic would be minimal when compared to existing traffic volumes on Santa Ana Blvd. and other affected streets, and its associated long-term noise level change would not be perceptible. Therefore, construction-related worker commutes and equipment transport noise impacts would be short-term and would not be adverse.

The second type of short-term noise impact would be from construction activities. Construction is performed in discrete steps, each of which has its own mix of equipment and consequently its own noise characteristics. These various, sequential phases would change the character of the noise generated and the noise levels as well along the project alignment as construction progresses. Despite the variety in the type and size of construction equipment, similarities in the dominant noise sources and patterns of operation allow construction-related noise ranges to be categorized by work phase. Table 8-1 lists typical construction equipment noise levels (Lmax) recommended for noise impact assessments, based on a distance of 50 feet between the equipment and a noise receptor.

Typical noise levels at 50 feet from an active construction area range up to 91 dBA Lmax during the noisiest construction phases. The site preparation phase, which includes grading and paving, tends to generate the highest noise levels because the noisiest construction equipment is earthmoving equipment. Earthmoving equipment includes excavating machinery such as backfillers, bulldozers, and front loaders. Earthmoving and compacting equipment includes compactors, scrapers, and graders. Typical operating cycles for these types of construction equipment may involve one or two minutes of full power operation followed by three or four minutes at lower power settings.

Construction of the proposed project is expected to require the use of earthmovers, bulldozers, water trucks, and pickup trucks. Noise associated with the use of construction equipment is estimated between 79 and 89 dBA Lmax at a distance of 50 feet from the active construction area for the grading phase. As seen in Table 8-1, the maximum noise level generated by each earthmover is assumed to be approximately 86 dBA Lmax at 50 feet from the earthmover in operation. Each bulldozer would generate approximately 85 dBA Lmax at 50 feet. The maximum noise level generated by water trucks and pickup trucks is approximately 86 dBA Lmax at 50 feet from these vehicles. Each doubling of the sound source with equal strength increases the noise level by 3 dBA. Each piece of construction equipment operates as an individual point source. The worst-case composite noise level at the nearest residence during this phase of construction would be 91 dBA Lmax (at a distance of 50 feet from an active construction area).

EXHIBIT 2
City Council 22 – 490 5/5/2026
Chapter 8. Construction Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
8-2
Table 8-1. Typical Construction Equipment Noise Levels
Type of Equipment
Range of Maximum Sound
Levels
(dBA Lmax at 50 feet)
Suggested Maximum Sound
Levels for Analysis
(dBA Lmax at 50 feet)
Pile Drivers 81 to 96 93
Rock Drills 83 to 99 96
Jackhammers 75 to 85 82
Pneumatic Tools 78 to 88 85
Pumps 74 to 84 80
Scrapers 83 to 91 87
Haul Trucks 83 to 94 88
Cranes 79 to 86 82
Portable Generators 71 to 87 80
Rollers 75 to 82 80
Dozers 77 to 90 85
Tractors 77 to 82 80
Front-End Loaders 77 to 90 86
Hydraulic Backhoe 81 to 90 86
Hydraulic Excavators 81 to 90 86
Graders 79 to 89 86
Air Compressors 76 to 89 86
Trucks 81 to 87 86
Source: Noise Control for Buildings and Manufacturing Plants, Bolt, Beranek & Newman, 1987. dBA = A-weighted decibels
Lmax = maximum instantaneous noise level
In addition to the standard construction equipment, the project may require the use of pile drivers. As shown in Table 8-1, pile driving generates noise levels of up to 96 dBA Lmax at 50 feet.

The closest sensitive receiver locations are located 50 feet from the project construction areas.

Therefore, these receptor locations may be subject to short-term noise reaching 95 dBA Lmax or higher generated by construction activities along the project alignment. Compliance with the construction hours specified in the City of Santa Ana Municipal Code, Noise Control Section 18- 314, would be required. See Section 4.2.3 on page 4-3 of this report. To minimize construction noise impacts on sensitive land uses adjacent to the project site, construction noise is regulated by the Caltrans Standard Specifications in Section 14-8.02, “Noise Control,” and also by Standard Special Provision S5-310, “Noise Control.” Noise control will conform to the provisions in Section 14-8.02 and Standard Special Provision S5-310. The noise level from the contractor’s operations between the hours of 9:00 p.m. and 6:00 a.m. will not exceed 86 dBA Leq(h) at a distance of 50 feet. This requirement in no way relieves the contractor from responsibility for complying with local ordinances regulating noise levels. The contractor should use an alternative warning method instead of a sound signal unless required by safety laws. In EXHIBIT 2
City Council 22 – 491 5/5/2026
Chapter 8. Construction Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
8-3
addition, the contractor will equip all internal combustion engines with the manufacturerrecommended mufflers and will not operate any internal combustion engine on the job site without the appropriate muffler.

Noise from construction activities are exempt from the City of Santa Ana Municipal Code noise ordinance, provided that construction work takes place between the hours of 7:00 a.m. and 8:00 p.m. on weekdays and Saturdays.

Construction noise would be short-term, intermittent, and overshadowed by local traffic noise.

Further, implementing the following measure would further minimize the temporary noise impacts from construction:
• The contractor will implement appropriate additional noise mitigation measures, including changing the location of stationary construction equipment, turning off idling equipment, rescheduling construction activity, notifying adjacent residents in advance of construction work, and installing acoustic barriers around stationary construction noise sources.

EXHIBIT 2
City Council 22 – 492 5/5/2026
Chapter 8. Construction Noise
Noise Study Report
Santa Ana Boulevard Grade Separation Project
8-4
This page intentionally left blank
EXHIBIT 2
City Council 22 – 493 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
9-1
Chapter 9 References
AECOM. 2011. Traffic Data. December. Orange, CA.

Bolt, Beranek & Newman. 1987. Noise Control for Buildings and Manufacturing Plants.

California Department of Transportation. 2009. Technical Noise Supplement. November.

Sacramento, CA: Division of Environmental Analysis. Available:
<http://www.dot.ca.gov/hq/env/noise/pub/tens_complete.pdf>. ———. 2006. Highway Design Manual. Publications Unit.
———. 2010. 2010 Standard Specifications and Special Provisions. ———. 2011. Traffic Noise Analysis Protocol for New Highway Construction, Reconstruction, and Retrofit Barrier Projects. Division of Environmental Analysis. May. Available:
<http://www.dot.ca.gov/hq/env/noise/pub/ca_tnap_may2011.pdf>.

Federal Highway Administration (Anderson, Grant S., Cynthia S. Y. Lee, Gregg G. Fleming). 1998a. FHWA Traffic Noise Model, Version 1.0: User's Guide. Report No. FHWA-PD96-009 and DOT-VNTSC-FHWA-98-1. Cambridge, MA: John A. Volpe National Transportation Systems Center, Acoustics Facility, January. ——— (Menge, Christopher W., Christopher J. Rossano, Grant S. Anderson, Christopher J.

Bajdek). 1998b. FHWA Traffic Noise Model, Version 1.0: Technical Manual. Report No.

FHWA-PD-96-010 and DOT-VNTSC-FHWA-98-2. Cambridge, MA: John A. Volpe National Transportation Systems Center, Acoustics Facility, February. ———. 2004. FHWA Traffic Noise Model, Version 2.5. Office of Environment and Planning.

Washington, D.C. February.

Santa Ana, City of. Municipal Code. November 28, 2011 (Supp. No. 7) Santa Ana, CA.

Available: < http://library.municode.com/index.aspx?clientId=14452> EXHIBIT 2
City Council 22 – 494 5/5/2026
Chapter 9 References
Noise Study Report
Santa Ana Boulevard Grade Separation Project
9-2
This page intentionally left blank
EXHIBIT 2
City Council 22 – 495 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
A-1
Appendix A Traffic Data
This appendix contains tables that present traffic data for the existing conditions, Design Year No Build, and Design Year Build.

EXHIBIT 2
City Council 22 – 496 5/5/2026
EXHIBIT 2
City Council 22 – 497 5/5/2026
Table A1: Santa Ana Boulevard Grade Separation Weekday AM Peak Hour Traffic Volumes

NB EB SB WB

ID INTERSECT SCENARIO L T R L T R L T R L T R
2 Santiago St/Santa Ana Blvd Existing 21 43 62 29 326 19 220 122 83 114 836 241 2016 Baseline 22 44 64 41 373 19 239 125 94 117 917 2692016 Baseline1 22 44 64 41 373 19 248 125 98 108 909 2732035 Baseline2 69 291 106 177 701 44 352 306 332 148 1086 6062035 + Project 69 291 106 177 701 44 361 306 336 139 1078 610 3 Logan St/Santa Ana Blvd Existing 0 0 0 0 616 0 0 0 21 0 1197 8 2016 Baseline1 0 0 0 0 683 0 0 0 22 0 1309 82016 + Project 0 0 0 0 683 0 0 0 0 0 1317 02035 Baseline3 0 0 0 0 742 0 0 0 24 0 1423 92035 + Project 0 0 0 0 742 0 0 0 0 0 1432 0 4 SARTC Dwy/Santa Ana Blvd Existing 0 0 35 0 581 39 0000 1201 0 2016 Baseline1 0 0 35 0 1323 39 0000 2633 0
2016 + Project 0 0 35 0 1384 39 0000 2702 0
2035 Baseline3 0 0 39 0 703 44 0000 1427 0
2035 + Project 0 0 39 0 712 44 0000 1414 0
5 Fuller St‐Fruit St/Santa Ana Blvd Existing 22 0 23 4 583 25 1 0 1 32 1148 6 2016 Baseline1 23 0 24 4 650 26 1 0 1 33 1259 6
2016 + Project 23 0 24 4 659 26 1 0 1 33 1259 6
2035 Baseline3 25 0 26 4 705 28 1 0 1 36 1368 7
2035 + Project 25 0 26 4 714 28 1 0 1 36 1368 7
6I‐5 SB Ramps/SanAna Blvd Existing 0 0 0 230 393 0 378 0 84 0 1114 264 2016 Baseline1 0 0 0 251 440 0 387 0 103 0 1207 2712016 + Project 0 0 0 251 449 0 387 0 103 0 1207 2712035 Baseline2 0 0 0 340 841 0 508 0 122 0 1203 2192035 + Project 0 0 0 340 850 0 508 0 122 0 1203 219 Source: AECOM. 2011 `
1 2016 Baseline traffic volumes developed by adding cumulative projects trip assignmentand application of 2 2035 Baseline traffic volumes referenced from Santa Ana Renaissanc Specific Plan Traffic Study (KOA 3 2035 Baseline traffic volumes developed by adding cumulative projects trip assignmentand application of

EXHIBIT
2 City Council 22 – 498 5/5/2026
Table A2: Santa Ana Boulevard Grade Separation Weekday PM Peak Hour Traffic Volumes

ID INTERSECT SCENARIO L T R L T R L T R L T R
Santiago St/Santa Ana Blvd Existing 42 77 104 240 128 61 43 750 16 103 439 142 2016 Baseline1 43 79 107 281 131 75 61 861 16 106 495 1572016 + Project 43 79 107 286 131 78 61 861 16 101 489 1622035 Baseline2 55 291 115 461 369 308 295 1018 126 148 907 5062035 + Project 55 291 115 466 369 311 295 1018 126 143 901 511 Logan St/Santa Ana Blvd Existing 0 0 0 0 0 14 0 1166 0 0 660 8 2016 Baseline1 0 0 0 0 0 14 0 1322 0 0 732 8
2016 + Project 0000000 1327 0 0 740 0
2035 Baseline3 0 0 0 0 0 16 0 1433 0 0 794 9
2035 + Project 0000000 1438 0 0 803 0
SARTC Dwy/Santa Ana Blvd Existing 0 0 97 0000 1076 33 0 680 0 2016 Baseline1 0 0 99 0000 1230 34 0 752 02016 + Project 0 0 99 0000 1235 34 0 760 02035 Baseline3 0 0 109 0000 1332 37 0 817 02035 + Project 0 0 109 0000 1337 37 0 826 0 Fuller St‐Fruit St/Santa Ana Blvd Existing 24 0 82 16 1 6 7 1149 15 14 648 3 2016 Baseline1 25 0 84 16 1 6 7 1305 15 14 719 32016 + Project 25 0 84 16 1 6 7 1310 15 14 719 32035 Baseline3 27 0 92 18 1 7 8 1414 17 16 781 32035 + Project 27 0 92 18 1 7 8 1419 17 16 781 3 I‐5 SB Ramps/SanAna Blvd Existing 0 0 0 296 0 83 663 608 0 0 571 193 2016 Baseline1 0 0 0 304 0 95 719 711 0 0 630 1992016 + Project 0 0 0 304 0 95 719 716 0 0 630 1992035 Baseline2 0 0 0 351 0 305 527 943 0 0 1324 2732035 + Project 0 0 0 351 0 305 527 948 0 0 1324 273 Source: AECOM. 2011
1 2016 Baseline traffic volumes developed by adding cumulative projects trip assignmentand application of 0.50% annual 2 2035 Baseline traffic volumes referenced from Santa Ana Renaissanc Specific Plan Traffic Study (KOA Corporatio 2010) 3 2035 Baseline traffic volumes developed by adding cumulative projects trip assignmentand application of 0.50% annual

EXHIBIT
2 City Council 22 – 499 5/5/2026
Noise Study Report
Santa Ana Boulevard Grade Separation Project
B-1
Appendix B Noise Barrier Reasonableness
Analysis Worksheet
WORKSHEET B-1

CALCULATION OF REASONABLE ALLOWANCE
PROJECT: SANTA ANA BOULEVARD GRADE