PROPOSED MARYWOOD DEVELOPMENT

Transcription

1 ACOUSTICAL ANALYSIS PROPOSED MARYWOOD DEVELOPMENT CITY OF ORANGE, CALIFORNIA PREPARED FOR VCS Environmental RANCH VIEJO ROAD, SUITE 100 SAN JUAN CAPISTRANO, CALIFORNIA PREPARED BY A/E Tech BEVERLY HILLS, CALIFORNIA November 17, 2014

2 Table of Contents 1. INTRODUCTION FUNDAMENTALS OF NOISE APPLICABLE NOISE CRITERIA City of Orange Noise Element of the General Plan City of Orange Municipal Code METHODOLOGY SETTING Existing Noise Environment POTENTIAL FUTURE NOISE IMPACTS CONSTRUCTION NOISE Demolition and Crushing Grading Excavation and Remediation OPERATIONAL NOISE Proposed Project Traffic Noise High School Alternative Traffic Noise MITIGATION CONSTRUCTION NOISE OPERATIONAL NOISE REFERENCES Appendix Appendix A: Acoustical Terminology Appendix B: Photographs of Noise Measurement Locations Appendix C: Construction Noise Calculation Data Sheets List of Figures Figure 1: Project Location..2 Figure 2: Proposed Project Site Plan..8 Figure 3: Noise Monitoring Locations...10 Figure 4: Long-Term Noise Measurement Results, Site LT Figure 5: Long-Term Noise Measurement Results, Site LT Figure 6: Noise Receiver Locations....17

3 1. INTRODUCTION The proposed project is a proposed 40-unit single-family residential development to be constructed on an approximately 15-acre site located along East Villa Real Drive east of North Santiago Boulevard in the City of Orange (see Figure 1). Since the proposed project is adjoining existing residential and other noise-sensitive land uses, a noise study is needed for the environmental documentation being prepared for the project. The purpose of this noise analysis is to quantify the existing noise environment in the vicinity of the project site, determine whether noise levels from construction and future use of the project cause a noticeable increase in the noise environment or exceed acceptable limits as defined by the City's noise regulations, and to provide recommendations for noise mitigation as may be required. The Conditional Use Permit (CUP) for the property also allows for the opportunity of a private high school with a maximum enrollment of 600 students. For comparison purposes, this analysis also evaluates the potential traffic noise effects of the High School Alternative. 2. FUNDAMENTALS OF NOISE Sound pressure can be measured in units of micro Newtons per square meter (µn/m 2 ) called micro Pascals (µpa). One µpa is approximately one-hundred-billionth of the normal atmospheric pressure. The pressure of a very loud sound may be 200,000,000 µpa, or 10,000,000 times the pressure of the weakest audible sound (20 µpa). Expressing sound levels in terms of µpa would be cumbersome because of this wide range. As such, sound pressure levels (SPL) are described in logarithmic units of ratios of actual sound pressures to a reference pressure squared. These units are called bels, named after Alexander G. Bell. To provide a finer resolution, a bel is subdivided into decibels (deci- or tenth of a bel), abbreviated db. Appendix A provides a description of the acoustical terminology used in this report. Unless otherwise stated, all sound levels reported are A-weighted sound pressure levels in decibels (dba). The A-weighting de-emphasizes lower-frequency sounds below 1,000 hertz (1 kilohertz [khz]) and higher-frequency sounds above 4 khz. It emphasizes sounds between 1 khz and 4 khz. A-weighting is the measure most commonly used for traffic and environmental noise throughout the world. Most community noise standards utilize A-weighting because it provides a high degree of correlation with human annoyance and health effects. Table 1 shows the relative A-weighted noise levels of common sounds measured in the environment and in industry for various sound levels. 1

4 Figure 1 Project Loca0on Project Site N

5 TABLE 1 TYPICAL SOUND LEVELS MEASURED IN THE ENVIRONMENT Noise Source At a Given Distance A-Weighted Sound Level (dba) Noise Environments Shotgun 140 Carrier flight deck Subjective Impression Civil defense siren (100 ft) 130 Jet Takeoff (200 ft) 120 Threshold of pain Loud rock music 110 Rock music concert Pile driver (50 ft) 100 Very loud Ambulance siren (100 ft) Freight cars (50 ft) Pneumatic drill (50 ft) Freeway (100 ft) 90 Boiler room Printing press plant 80 Noisy restaurant Busy traffic; hair dryer 70 Moderately loud Normal conversation (5 ft) 60 Data processing center Air conditioning unit (100 ft) Department store Light traffic (100 ft); rainfall 50 Private business office Large transformer (200 ft) Bird calls (distant) 40 Average living room library Soft whisper (5 ft); rustling leaves 30 Quiet bedroom 20 Recording studio Quiet Normal breathing Threshold of hearing The actual impact of noise is not a function of loudness alone. The time of day noise occurs and its duration of the noise are also important. In addition, most noise that lasts for more than a few seconds is variable in its intensity. Consequently, a variety of noise descriptors have been used such as L10, L50, and Ldn. The noise descriptor used for this study is the Leq. 3

6 The Leq is the equivalent steady-state sound level that, within a stated period of time, would contain the same acoustical energy as the time-varying sound level during the same period. The Leq (h) is the energy-average of the A-weighted sound levels, occurring during a 1-hour period, in decibels (i.e., a 1-hour Leq). From the source to the receiver, noise changes both in level and frequency spectrum. The most obvious is the decrease in noise as the distance from the source increases. The manner in which noise decreases with distance depends on: Geometric spreading from point and line sources Ground absorption Atmospheric effects and refraction Shielding by natural and man-made features, noise barriers, diffraction, and reflection Sounds from a small localized source (approximating a point source) radiates uniformly outward as it travels away from the source in a spherical pattern. The sound level decreases or drops-off at a rate of 6 dba for each doubling of the distance (6 dba/dd). However, highway traffic noise is not a single, stationary point source of sound. The movement of the vehicles makes the source of the sound appear to emanate from a line (line source) rather than a point when viewed over some time interval. Changes in noise levels are typically perceived by the human ear as follows: A 3-dBA change is barely perceptible A 5-dBA change is readily perceptible A 10-dBA change is perceived as a doubling or halving of noise 3. APPLICABLE NOISE CRITERIA 3.1 City of Orange Noise Element of the General Plan The City of Orange Noise Element of the General Plan (City of Orange, 2010) establishes land use compatibility criteria in terms of the Community Noise Equivalent Level (CNEL) and average noise level (Leq) for noise-sensitive developments, including residential uses. The City has adopted a land use compatibility threshold of 65 db CNEL for exterior noise levels in outdoor activity areas of residential developments (refer to Table N-3 of the Noise Element). The CNEL limit is essentially employed for transportation noise sources, such as vehicular 4

7 traffic noise. The City s stationary noise source limit for noise-sensitive land uses is 55 db hourly Leq during daytime hours of 7 a.m. to 10 p.m. and 45 db hourly Leq during nighttime hours between 10 p.m. to 7 a.m. (Table N-4 of the Noise Element). The City has also established maximum (Lmax) limits for noise from stationary sources of 70 and 65 db during daytime and nighttime hours, respectively, at noise-sensitive land uses. The intent of the exterior noise level requirements of the Noise Element is to provide an acceptable noise environment for outdoor activities and recreation. For analysis of noise impacts and determining appropriate mitigation under the California Environmental Quality Act (CEQA), in addition to the allowable noise level standards outlined above, an increase in ambient noise levels is assumed to be a significant noise impact if a project causes ambient noise levels to exceed the following: Where the existing ambient noise level is less than 65 db, a project related permanent increase in ambient noise levels of 5 db CNEL or greater. Where the existing ambient noise level is greater than 65 db, a project related permanent increase in ambient noise levels of 3 db CNEL or greater. 3.2 City of Orange Municipal Code Chapter 8.24 of the City of Orange Municipal Code (updated 2014) pertains to noise control within the City s boundaries. The purpose of this chapter of the Municipal Code is that in order to control unnecessary, excessive and annoying sounds emanating from the City, it is the policy of the City to regulate such sounds generated from all sources as specified in this chapter. The intent of this chapter is to protect residential land uses from unnecessary, excessive and annoying sounds. Table of the Municipal Code shows fixed source exterior noise standards for noise-sensitive land uses. The established standards in the Municipal Code are 55 db hourly Leq for hours of 7 a.m. to 10 p.m. and 50 db hourly Leq for hours between 10 p.m. to 7 a.m. The Municipal Code has also established maximum (Lmax) limits for noise from fixed sources of 70 and 65 db during daytime and nighttime hours, respectively, at noise-sensitive land uses. Subsection of the Municipal Code further clarifies that: In the event the ambient noise level exceeds the noise standards identified in Table of this section, the adjusted ambient noise level shall be applied as the noise 5

8 standard. In cases where the noise standard is adjusted due to a high ambient noise level, the noise standard shall not exceed the adjusted ambient noise level, or 70 db (A), whichever is less. In cases where the ambient noise level is already greater than 70 db (A), the ambient noise level shall be applied as the noise standard. The Municipal Code exempts noise sources associated with construction, repair, remodeling, or grading of any real property, provided said activities take place between the hours of 7:00 a.m. and 8:00 p.m. on any day except for Sunday or a Federal holiday, or between the hours of 9:00 a.m. and 8:00 p.m. on Sunday or a Federal holiday. Noise generated outside of the hours specified by the Code would be subject to the City s noise standards described above. 4. METHODOLOGY To quantify the existing noise environment in the vicinity of the project site, a noise measurement survey consisting of long-term (24-hour) and short-term (20-minute) noise measurements was conducted at eight locations representative of noise-sensitive receivers nearest to the project site. The noise monitoring locations include two 24-hour measurement sites located near the northeast and southeast parts of the project site, and six short-term sites representing other noise-sensitive uses surrounding the project site. For assessment of potential future noise impacts due to the proposed project, temporary noise exposure during the construction phase and permanent noise effects due to traffic generated by the project were evaluated. Noise levels due to construction of the proposed project are estimated based upon available reference noise level data from construction equipment (FHWA, 2006), distance between construction activities and nearest identified noise-sensitive receiver locations, and shielding effects of local terrain, where applicable. Traffic noise levels were evaluated using the Federal Highway Administration (FHWA) Traffic Noise Model (TNM) version 2.5 computer program. TNM is the latest analytical method developed for roadway traffic noise prediction. The model is based upon reference energy emission levels for automobiles, medium trucks (2 axles), heavy trucks (3 or more axles), buses and motorcycles, with consideration given to vehicle volume, speed, roadway configuration, distance to the receiver, atmospheric conditions, and the acoustical characteristics of the site. TNM was developed to predict hourly Leq values for free-flowing and interrupted-flow traffic conditions. 6

9 Traffic data used in the noise model were developed from the traffic impact study data provided by the project traffic consultant (RK Engineering Group, 2014). Opening year (2017) peak-hour traffic volumes on East Villa Real Drive and North Santiago Boulevard with and without the project were utilized in TNM to assess potential increases in traffic noise levels due to the proposed project. 5. SETTING The project site is located east of State Route 55 (SR-55) and North Santiago Boulevard, along East Villa Real Drive in City of Orange. Figure 1 is a current aerial of the project site, showing the subject property, currently the Marywood Pastoral Center, and the surrounding properties. Figure 2 is the proposed project site plan. The Marywood Pastoral Center is currently developed with 14 buildings totaling approximately 102,000 square feet of religious, educational, and office uses. The property was originally developed by the Sisters of Providence of Saint Mary-of-the-Woods, Indiana, as a high school (Marywood High School), completed in The high school was sold to the Diocese of Orange in 1979, closed after graduation in 1981, and converted to a pastoral center for the diocese. The buildings and facilities within the project site are currently vacated and not in use, however, the site grounds are being maintained regularly. Inspection of the site environs indicated that the project site is mostly flat with a slight north-to-south slope. The northeast portion of the site is elevated above the rest of the site by more than 45 feet. The adjoining land uses around the project site are primarily single-family residential. Other adjacent land uses include the Child Time Day Care, located east of the project site, and municipal land uses where the City s water tanks are located (see Figure 1). Residential uses to the east and southeast of the project site, along East Villa Real Drive and North Maple Grove Road, are at approximately the same elevation as the project site. Homes located northeast of the project site, at the end of East Marywood Lane, are elevated in excess of 50 feet above the project site, and residences to the west and north of the project site are between approximately 20 to 150 feet below the existing project grade. 7

10 N Figure 2 Proposed Project Site Plan

11 5.1 Existing Noise Environment The sources of noise currently affecting the project site include sparse local vehicular traffic on Villa Real Drive, distant traffic on Santiago Boulevard and SR-55, occasional distant aircraft overflights, and gardening activities that are typical of a residential setting. Existing ambient noise levels in the project environs were quantified based upon two long-term (24-hour) and six short-term (20-minute) noise level measurements conducted at locations representative of the nearest noise-sensitive uses adjoining the project site. The noise monitoring locations are depicted on Figure 3. Long-term noise monitoring locations are shown as LT-1 and LT-2, and short-term noise monitoring locations are shown as location ST-1 through ST-6. Following are brief descriptions of the noise monitoring locations: LT-1: This 24-hour noise monitoring site is located within the project site at a location nearest to and representative of the existing residences at the end of East Marywood Lane. LT-2: This 24-hour noise monitoring site is located at the southeast part of the project site, and represents background noise levels at existing residences along East Villa Real Drive and North Maple Grove Road nearest to the project site. ST-1: This short-term location is at the north fence line of the project site overlooking the residences north of the project site along East Denise Avenue. ST-2: This short-term location is at the northwest property fence of the project overlooking the residences along East Denise Avenue, west of the project site. ST-3: This short-term monitoring site is located adjacent to the east property fence next to the Child Time Day Care parking area. The background noise levels at this location were obtained at a quiet time when the children were inside the Day Care building. ST-4: This short-term monitoring location is at the top of the west project site slope overlooking and representative of the homes west of the project site. ST-5: This short-term monitoring site is located at the end of East Altura Avenue cul-de-sac, and represents the homes located to the southwest of the project site. ST-6: This short-term monitoring site is located in front of the home at 6228 East Denise Avenue, and represents the nearest homes located to the north of the project site. 9

12 Figure 3 Noise Monitoring Loca0ons ST - 6 LT - 1 ST - 1 ST - 2 ST - 3 ST - 5 ST - 4 LT - 2 N LT - # ST - # Long- Term Noise Monitoring Loca6ons Short- Term Noise Monitoring Loca6ons

13 Instrumentation utilized for the measurement of existing noise levels included two Bruel & Kjaer (B&K) Model 2238 sound level meters equipped with B&K Type 4188 ½" microphones. The instrumentation was calibrated prior to each measurement with a B&K Type 4240 acoustical calibrator to ensure the accuracy of the measurements. All measurement equipment complies with applicable specifications of the American National Standards Institute (ANSI) and the International Electrotechnical Commission (IEC) for the Type I (precision) sound level meters. The microphone was located on a tripod at 5 feet above the ground. The noise level measurements were conducted on Friday, August 22, and Thursday and Friday, August 28 and 29, 2014 at the locations noted on Figure 3. The noise measurements at the long-term monitoring locations included hourly average background noise level (Leq), L10 (level exceeded 10 percent of the time) and L90 (level exceeded 90 percent of the time). At each of the short-term monitoring locations, the measurements included one 20-minute continuous sample of background noise, for which Leq, Lmin (minimum sound level), and Lmax (maximum sound level) were recorded. Appendix B depicts photographs of the noise monitors at each of the eight monitoring locations. Table 2 and Figures 4 and 5 summarize the measured background noise levels at long-term sites LT-1 and LT-2. For each of these locations, the 24-hour CNEL is also calculated and shown in Table 2. The measured background sound levels reported in Table 2 may be compared to the noise level standards of the City to determine if existing noise levels exceed the City's applicable noise level criteria. From the measured background sound level data at these two long-term locations, it is apparent that hourly average sound levels during both daytime and nighttime hours at location LT-1 are below the City s exterior noise standards of 55 and 50 db, respectively. Therefore, the City s standards are applicable without adjustment at the nearest residential locations northeast of the project site that represented by site LT-1. At location LT-2, the highest hourly average measured background sound levels during both daytime and nighttime hours are 59 db. Therefore, the City s standards may be adjusted to this level for homes located southeast of the project along East Villa Real Drive. The measured CNEL values are also well below the City s exterior standard of 65 db CNEL for exterior areas of noise-sensitive land uses. 11

14 Measurement Start Time Table 2 Marywood 24-hour Noise Monitoring Results August 28-29, 2014 Measured Sound Levels, dba Site LT-1 Site LT-2 Leq L10 L90 Leq L10 L90 10: : : : : : : : : : : : : : : : : : : : : : : : CNEL Source: A/E Tech 12

15 Sound Level, dba Figure 4 Long-Term Noise Measurement Results Site LT-1 August 28-29, 2014 Time Leq L10 L90 Sound Level, dba Figure 5 Long-Term Noise Measurement Results Site LT-2 August 28-29, 2014 Time Leq L10 L90 13

16 Summary of the noise levels measured during the short-term sampling effort is shown in Table 3. The results of short-term background noise measurements indicate that existing daytime noise levels at the noise-sensitive receivers represented by these measurements are below the noise standard of 55 db hourly Leq applied by the City of Orange Municipal Code and General Plan Noise Element for residential and other noise-sensitive areas. Therefore, the City s noise level limits may be applied to the Day Care and homes along the west and north sides of the project site. TABLE 3 Monitoring Location Summary of Measured Short-Term Background Noise Levels (db) Marywood Development Project Measurement Date Measurement Start Time Duration (minutes) Leq Lmax Lmin ST-1 8/22/14 11:46 a.m ST-2 8/22/14 12:09 p.m ST-3 8/22/14 12:39 p.m ST-4 8/29/14 10:38 a.m ST-5 8/29/14 11:09 a.m ST-6 8/29/14 11:39 a.m Source: A/E Tech 6. POTENTIAL FUTURE NOISE IMPACTS Potential future noise impacts from the proposed project would include short-term, temporary effects during the construction phase of the project and permanent effects resulting from increased traffic brought on the local roadway system by the proposed project. This section describes the methods, data, and findings of the construction and traffic noise analyses performed to determine the level of impacts, and whether predicted noise exposure would be in compliance with the City s applicable noise criteria. 14

17 6.1 CONSTRUCTION NOISE During the construction of the proposed project, overall noise levels would vary based on the level of construction activity, the types of equipment used, when the equipment is being operated, and the distance from construction activities to noise-sensitive receivers. Construction of the proposed project will take place in several distinct phases, including demolition of existing structures and removal of concrete hardscape and pavement, followed by excavation and remedial grading of the site, then final grading, and ultimately final construction of buildings and roadways within the project site. The City of Orange encourages recycling of construction materials. Therefore, as an option, the demolition phase of construction may include creating a temporary aggregate plant on the project site to crush the existing concrete and asphalt into suitable sizes of rocks to use as base. The aggregate plant would be located near the center of the project site Demolition and Crushing Demolition of buildings and hardscape within the project site is currently proposed to take place in August and September The hardscape and building demolition activities will be non-overlapping, with the hardscape demolition occurring in 10 working days of 8-hour shifts, followed by 20 work days of 8-hour shifts to demolish the buildings within the project site. Crushing operations would occur immediately after the demolition phase, and is expected to last for 10 days, operating for 8 hours each day. Construction equipment utilized for demolition of buildings and hardscape will include loaders, dozers, articulated hauler, excavators, and other industrial equipment. The crushing and screening plant will include a crusher, screen, conveyors, receiving hopper, grizzly, and jaw crusher. Typical construction equipment noise level data were obtained from the Roadway Construction Noise Model developed by FHWA (FHWA, 2006). The noise database utilized for estimating construction noise levels includes maximum noise levels from each piece of machinery at a reference distance of 50 feet and usage factors of equipment as percentages during a typical activity hour. For each construction equipment, the Leq is estimated using its reference noise level and usage factor combined with the distance to the receiver and local shielding factors, if applicable. Distance attenuation effect on noise levels from a construction point source is 6 db per doubling of distance. 15

18 Five receivers at neighboring noise-sensitive locations near the noise monitoring sites were selected for the construction noise analysis. Figure 6 shows the selected noise-sensitive receivers where construction noise levels are predicted. Construction noise levels in terms of hourly Leq and Lmax were estimated for the demolition and crushing phase of the proposed project at these locations. For each receiver location, a range of noise levels was estimated to show noise levels from demolition at its nearest to farthest distances to the given receiver. Appendix C shows the construction noise calculation data and Table 4 summarizes the noise estimation results for the demolition and crushing phase. TABLE 4 Estimated Construction Noise Levels (db) Marywood Development Project Demolition and Crushing Operations Receiver Location Nearest Measurement Location Estimated Leq Demolition Hardscape Buildings Crushing Lmax (Crushing & Demolition) 1 LT ST LT ST ST Source: A/E Tech From the data in Table 4 it is apparent that construction noise levels during the demolition and crushing phase would exceed the existing background noise levels at the neighboring noise-sensitive receivers. Construction noise levels would be clearly audible at the exterior areas of adjoining homes and the day care, however, construction activities would occur only during daytime hours and for a limited duration. These construction activities are exempt from the City s noise ordinance. 16

19 Figure 6 Noise Receiver Loca1ons N # Noise Receiver Loca-ons

20 6.1.2 Grading Excavation and Remediation The grading phase of construction will include remedial grading of the existing project site fills located along the western side of the project site near the City water tanks, and final grading throughout the property to prepare the site for construction of buildings and roadways. Grading activities are anticipated to occur between October 2015 and February 2016, and would include 45 days of peak activity followed by 15 construction days of smaller spreads and 15 days of finishing activities. The equipment to be utilized during the peak grading activities period include six (6) scrapers, three dozers, one motor grader, and two water trucks. Similar to the demolition phase, noise levels for the peak grading phase of construction were estimated by using the equipment reference noise levels, and applying distance attenuation and local shielding effects. Data sheets in Appendix C show the results of the noise level calculations. Table 5 shows summaries of the noise level estimates from peak grading operations. TABLE 5 Receiver Location Estimated Construction Noise Levels (db) Marywood Development Project Peak Grading Operations Nearest Measurement Location Estimated Highest Hourly Leq Estimated Lmax 1 LT ST LT ST ST Source: A/E Tech From the data in Table 5 it is apparent that construction noise levels during the grading phase would also exceed existing background noise levels at the neighboring noise-sensitive receivers. Noise levels from grading activities would be clearly audible at the exterior areas of adjoining homes and the day care, however, such activities would occur only during daytime hours and are also exempted by the City. 18

21 Noise would also be generated during the construction phase by increased truck traffic associated with transport of materials and equipment on area roadways. This noise increase would be of short duration and would occur only during daytime hours, consistent with the City s noise ordinance. The City of Orange exempts construction activities from its noise level limits between the hours of 7 a.m. and 8 p.m. on weekdays and between 9 a.m. and 8 p.m. on Sundays and holidays. It is recommended that construction of the proposed project be limited to the exempted daytime hours on weekdays. 6.2 OPERATIONAL NOISE Long-term noise effects of the proposed project on nearby noise-sensitive uses would only be due to increased vehicular traffic on the local roadways generated by the proposed project. The High School Alternative would result in potential noise effects due to traffic, outdoor activities of students, and occasional loudspeaker announcements. For comparison purposes, this analysis quantifies noise effects of increased traffic on local roadways due to the proposed project and the High School Alternative Proposed Project Traffic Noise The proposed project will add traffic to the local roadway system on a daily basis. Future vehicular traffic generated by the project would utilize the entry gate on East Villa Real Drive as the only access to the project site. Potential increases in traffic noise exposure due to vehicle trips generated by the proposed project were evaluated using forecast traffic volumes on local roadways in the project opening year (2017) with and without the proposed project. The traffic data were utilized in the FHWA TNM version 2.5 to evaluate the differences in hourly average traffic noise level (Leq) between the with- and without-project scenarios. Table 6 summarizes the comparison of calculated 2017 AM peak-hour Leq values between the with-project and without-project scenarios. As shown in Table 6, the proposed project would only cause less than a 1-dB increase during AM peak hour along East Villa Real Drive near the project entry gate, and no increase in traffic noise levels at locations farther from the project site. Therefore, project traffic would not result in adverse effects on any nearby noise-sensitive uses. On a daily basis, the proposed project would increase the average daily traffic (ADT) volume on East Villa Real Drive by 343 vehicles. In project buildout year (2017), the ADT would increase from approximately 2,300 vehicles to approximately 2,600 vehicles. Noise effect of such an 19

22 increase in daily volumes on the CNEL at locations along the roadway would be a 0.5 db increase. Therefore, increase in daily average traffic noise levels would also be insignificant High School Alternative Traffic Noise The High School Alternative would generate a total of 1,488 trip-ends per day, with 486 vehicle trips during the AM peak hour and 102 vehicle trips during the PM peak hour. Compared to the proposed residential development, the private high school would generate an additional 1,107 trip-ends per day, with an additional 455 vehicle trips during the AM peak hour and an additional 62 vehicle trips during the AM peak hour. Similar to traffic noise calculations, 2017 buildout traffic noise levels were estimated for the High School Alternative using the AM peak hour traffic volumes in the TNM model. The results of the hourly traffic Leq estimations with and without the High School Alternative are compared in Table 6. From the data presented in Table 6 it is apparent that the High School Alternative would result in a clearly noticeable increase in traffic noise during the AM peak hour along the segment of East Villa Real Drive between North Santiago Boulevard and the project entry gate. Under the High School Alternative, increases in traffic noise levels elsewhere would be insignificant but greater than those caused by the proposed project. In terms of CNEL, the High School Alternative would result in an increase of approximately 1.3 db in traffic noise levels along East Villa Real Drive. 20

23 Table 6 Comparison of AM Peak-Hour Traffic Leq (db) Between With Project and Without Project Buildout (2017) Proposed Marywood Development Project and High School Alternative Roadway Segment Buildout (2017) AM Peakhour Traffic Volume Without Project With Project Predicted Peak-hour Traffic Noise Level at 100 ft from Roadway Centerline Without Noise Level Project With Project Increase Proposed Project Villa Real Drive - SB Just North of Entry Gate Villa Real Drive - NB Just North of Entry Gate Villa Real Drive - SB Just South of Entry Gate Villa Real Drive - NB Just South of Entry Gate Villa Real Drive - WB East of Santiago Boulevard Villa Real Drive - EB East of Santiago Boulevard Santiago Boulevard - SB Just South of Villa Real Drive Santiago Boulevard - NB Just South of Villa Real Drive Santiago Boulevard - SB Just North of Villa Real Drive Santiago Boulevard - NB Just North of Villa Real Drive High School Alternative Villa Real Drive - SB Just North of Entry Gate Villa Real Drive - NB Just North of Entry Gate Villa Real Drive - SB Just South of Entry Gate Villa Real Drive - NB Just South of Entry Gate Villa Real Drive - WB East of Santiago Boulevard Villa Real Drive - EB East of Santiago Boulevard Santiago Boulevard - SB Just South of Villa Real Drive Santiago Boulevard - NB Just South of Villa Real Drive Santiago Boulevard - SB Just North of Villa Real Drive Santiago Boulevard - NB Just North of Villa Real Drive

24 7. MITIGATION 7.1 CONSTRUCTION NOISE Estimated noise exposure due to construction of the proposed project would exceed the existing background sound levels during daytime hours. The City exempts construction activities from its Municipal Code noise requirements between the hours of 7 a.m. and 8 p.m. on weekdays and Saturdays and between 9 a.m. and 8 p.m. on Sundays and holidays. Therefore, it is recommended that the project construction times be limited to weekdays during the exempted hours. Further, to minimize annoyance of neighboring noise-sensitive uses, it is recommended that the contractors develop construction noise mitigation plans that include: Using equipment engines fitted with mufflers, Placing construction staging and equipment storage areas at locations as far away from noise-sensitive locations as possible. 7.2 OPERATIONAL NOISE Future project-generated traffic on local area roadways would not cause a significant increase in noise levels. Therefore, noise mitigation will not be required for permanent effects of the proposed project. 22

25 8. REFERENCES City of Orange General Plan, Noise Element, Adopted March Available at: < Municipal Code, Chapter 8.24, Noise Control, April Federal Highway Administration FHWA Traffic Noise Model (FHWA TNM ) Technical Manual, February Roadway Construction Noise Model. February 15, Available at: < RK Engineering Group Marywood Development Traffic Impact Study. October 20, Marywood Alternative Development Summary Letter. October 20,

26 Appendix A Acoustical Terminology List of Technical Terms Decibel, db Term Frequency, Hz A-Weighted Sound Level, dba Definitions A unit describing the amplitude of sound, equal to 20 times the logarithm to the base of 10 of the ratio of the pressure of the sound measured to the reference pressure, which is 20 micropascals (20 micronewtons per square meter). The number of complete pressure fluctuations per second above and below the atmospheric pressure. The sound pressure level in decibels as measured on a sound level meter using the A-weighting filter network. The A-weighting filter deemphasizes the very low and very high frequency components of the sound in a manner similar to the frequency response of the human ear and correlates well with subjective reactions to noise. All sound levels in this report are A-weighted, unless reported otherwise. L01, L10, L50, L90 The A-weighted noise levels that are exceeded 1, 10, 50 and 90 percent of the time during the measurement period. Equivalent Noise Level, Leq Community Noise Equivalent Level, CNEL Lmax, Lmin Ambient Noise Level The average A-weighted noise level during the measurement period. The average A-weighted noise level during a 24-hour day, obtained after addition of 5 decibels in the evening from 7:00 p.m. to 10:00 p.m. and after the addition of 10 decibels to sound levels measured in the night between 10:00 p.m. and 7:00 a.m. The maximum and minimum A-weighted noise level during the measurement period. The composite of noise from all sources near and far. The normal or existing level of environmental noise at a given location.

27 Appendix B Noise Monitors Photographs

28 B-1. Noise Measurement Photographs at Site LT-1

29 B-2. Noise Measurement Photographs at Site LT-2

30 B-3. Noise Measurement Photographs at Site ST-1

31 B-4. Noise Measurement Photographs at Site ST-2

32 B-5. Noise Measurement Photographs at Site ST-3

33 B-6. Noise Measurement Photographs at Site ST-4

34 B-7. Noise Measurement Photographs at Site ST-5

35 B-8. Noise Measurement Photographs at Site ST-6

36 Appendix C Construction Noise Level Calculations

37 C-1 Building Demolition Nearest Distances 1 Distance 340 Usage Receiver Shielding 10 Factor 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 410 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 200 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 550 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 295 Usage Receiver Shielding 10 Factor 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50%

38 C-2 Building Demolition Longest Distances 1 Distance 920 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 710 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 680 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 885 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 870 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50%

39 C-3 Hardscape Demolition Nearest Distances 1 Distance 285 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 120 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 75 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 490 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 200 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50%

40 C-4 Hardscape Demolition Longest Distances 1 Distance 985 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 775 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 740 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 1170 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50% Distance 980 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Loader 1 40% Dozer 1 40% Excavator 1 50%

41 C-5 Crushing Operations 1 Distance 665 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Jaw Crusher 1 70% Cone Crusher 1 70% Screens 1 100% Conveyors 1 100% Distance 520 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Jaw Crusher 1 70% Cone Crusher 1 70% Screens 1 100% Conveyors 1 100% Distance 335 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Jaw Crusher 1 70% Cone Crusher 1 70% Screens 1 100% Conveyors 1 100% Distance 760 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Jaw Crusher 1 70% Cone Crusher 1 70% Screens 1 100% Conveyors 1 100% Distance 650 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Jaw Crusher 1 70% Cone Crusher 1 70% Screens 1 100% Conveyors 1 100%

42 C-6 Grading Operations Nearest Location Distance 120 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 120 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 75 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 360 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 200 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 1 50% Water Truck 1 100%

43 C-7 Grading Operations Center Location Distance 565 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Dozer 4 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 490 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Dozer 4 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 455 Usage Receiver Shielding 0 Factor 50 ft Lmax Hourly Leq Leq Lmax Dozer 4 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 770 Usage Receiver Shielding 5 Factor 50 ft Lmax Hourly Leq Leq Lmax Dozer 4 40% Scraper 1 40% Grader 1 50% Water Truck 1 100% Distance 590 Usage Receiver Shielding 10 Factor 50 ft Lmax Hourly Leq Leq Lmax Dozer 4 40% Scraper 1 40% Grader 1 50% Water Truck 1 100%

44 C-8 Grading Operations Farthest Location Distance 565 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 0 0% Water Truck 0 0% Distance 490 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 0 0% Water Truck 0 0% Distance 455 Usage Source Receiver Shielding 0 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 0 0% Water Truck 0 0% Distance 770 Usage Source Receiver Shielding 5 50 ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 0 0% Water Truck 0 0% Distance 590 Usage Source Receiver Shielding ft Lmax Hourly Leq Leq Lmax Dozer 1 40% Scraper 1 40% Grader 0 0% Water Truck 0 0%