Attachment G: Environmental Noise Assessment

Attachment G: Environmental Noise Assessment

IN-N-OUT BURGER, NORTH MAIN STREET ENVIRONMENTAL NOISE ASSESSMENT PLEASANT HILL, CALIFORNIA June 10, 2010 Prepared for: Rebecca Gorton Lamphier-Gregory 1944 Embarcadero Oakland, CA 94606 Prepared by: Jared M. McDaniel ILLINGWORTH & RODKIN, INC. Acoustics Air Quality 505 Petaluma Boulevard South Petaluma, CA 94952 (707) 766-7700 Job No.: 10-053

Introduction This report presents the results of the environmental noise assessment of the In-N-Out Burger project proposed west of North Main Street in Pleasant Hill, California. The project plans to construct a one-story restaurant with a drive-through. Parking will be located adjacent to the building in a surface parking lot. The report evaluates the potential noise impacts from the project with respect to applicable CEQA guidelines and local regulatory criteria. Included in this report is a brief description of the fundamentals of environmental noise, a summary of the applicable regulatory criteria, and the results of the project s noise monitoring survey. Future noise levels at the site and surrounding areas are calculated and summarized. The report then evaluates impacts resulting from the project in terms of noise and land use compatibility, temporary noise level increases resulting from project construction, and permanent noise level increases resulting from the operation of the project. Mitigation is presented to reduce significant impacts resulting from the project to less than significant levels. Fundamentals of Environmental Acoustics Noise may be defined as unwanted sound. Noise is usually objectionable because it is disturbing or annoying. The objectionable nature of sound could be caused by its pitch or its loudness. Pitch is the height or depth of a tone or sound, depending on the relative rapidity (frequency) of the vibrations by which it is produced. Higher pitched signals sound louder to humans than sounds with a lower pitch. Loudness is intensity of sound waves combined with the reception characteristics of the ear. Intensity may be compared with the height of an ocean wave in that it is a measure of the amplitude of the sound wave. In addition to the concepts of pitch and loudness, there are several noise measurement scales, which are used to describe noise in a particular location. A decibel (db) is a unit of measurement, which indicates the relative amplitude of a sound. The zero on the decibel scale is based on the lowest sound level that the healthy, unimpaired human ear can detect. Sound levels in decibels are calculated on a logarithmic basis. An increase of 10 decibels represents a ten-fold increase in acoustic energy, while 20 decibels is 100 times more intense, 30 decibels is 1,000 times more intense, etc. There is a relationship between the subjective noisiness or loudness of a sound and its intensity. Each 10-decibel increase in sound level is perceived as approximately a doubling of loudness over a fairly wide range of intensities. Technical terms are defined in Table 1. There are several methods of characterizing sound. The most common in California is the A- weighted sound level or dba. This scale gives greater weight to the frequencies of sound to which the human ear is most sensitive. Representative outdoor and indoor noise levels in units of dba are shown in Table 2. Because sound levels can vary markedly over a short period of time, a method for describing either the average character of the sound or the statistical behavior of the variations must be utilized. Most commonly, environmental sounds are described in terms of an average level that has the same acoustical energy as the summation of all the time-varying events. This energy-equivalent sound/noise descriptor is called L eq. The most common averaging period is hourly, but L eq can describe any series of noise events of arbitrary duration. 1

The scientific instrument used to measure noise is the sound level meter. Sound level meters can accurately measure environmental noise levels to within about plus or minus 1 dba. Various computer models are used to predict environmental noise levels from sources, such as roadways and airports. The accuracy of the predicted models depends upon the distance the receptor is from the noise source. Close to the noise source, the models are accurate to within about plus or minus 1 to 2 dba. Since the sensitivity to noise increases during the evening and at night -- because excessive noise interferes with the ability to sleep -- 24-hour descriptors have been developed that incorporate artificial noise penalties added to quiet-time noise events. The Community Noise Equivalent Level, CNEL, is a measure of the cumulative noise exposure in a community, with a 5 db penalty added to evening (7:00 pm - 10:00 pm) and a 10 db addition to nocturnal (10:00 pm - 7:00 am) noise levels. The Day/Night Average Sound Level, DNL or L dn, is essentially the same as CNEL, with the exception that the evening time period is dropped and all occurrences during this threehour period are grouped into the daytime period. 2

TABLE 1 Definitions of Acoustical Terms Used in this Report Term Decibel, db Definitions A unit describing the amplitude of sound, equal to 20 times the logarithm to the base 10 of the ratio of the pressure of the sound measured to the reference pressure. The reference pressure for air is 20. Sound Pressure Level Frequency, Hz A-Weighted Sound Level, dba Sound pressure is the sound force per unit area, usually expressed in micro Pascals (or 20 micro Newtons per square meter), where 1 Pascal is the pressure resulting from a force of 1 Newton exerted over an area of 1 square meter. The sound pressure level is expressed in decibels as 20 times the logarithm to the base 10 of the ratio between the pressures exerted by the sound to a reference sound pressure (e.g., 20 micro Pascals). Sound pressure level is the quantity that is directly measured by a sound level meter. The number of complete pressure fluctuations per second above and below atmospheric pressure. Normal human hearing is between 20 Hz and 20,000 Hz. Infrasonic sound are below 20 Hz and Ultrasonic sounds are above 20,000 Hz. The sound pressure level in decibels as measured on a sound level meter using the A-weighting filter network. The A-weighting filter de-emphasizes 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. Equivalent Noise Level, Leq Day-Night Level, DNL or L dn Community Noise Exposure Level, CNEL L 1, L 10, L 50, L 90 Ambient Noise Level The average A-weighted noise level during the measurement period. The hourly Leq used for this report is denoted as dba L eq[h]. The equivalent noise level for a continuous 24-hour period with a 10-decibel penalty imposed during nighttime and morning hours (10:00 pm to 7:00 am). CNEL is the equivalent noise level for a continuous 24-hour period with a 5-decibel penalty imposed in the evening (7:00 pm to 10:00 pm) and a 10-decibel penalty imposed during nighttime and morning hours (10:00 pm to 7:00am) The A-weighted noise levels that are exceeded 1%, 10%, 50%, and 90% of the time 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. Intrusive That noise which intrudes over and above the existing ambient noise at a given location. The relative intrusiveness of a sound depends upon its amplitude, duration, frequency, and time of occurrence and tonal or informational content as well as the prevailing ambient noise level. Source: Handbook of Acoustical Measurements and Noise Control, Harris, 1998. 3

TABLE 2 Typical Noise Levels in the Environment Common Outdoor Noise Source Noise Level (dba) Common Indoor Noise Source 110 dba Rock band Jet fly-over at 1,000 feet 100 dba Gas lawn mower at 3 feet 90 dba Diesel truck at 50 feet at 50 mph Food blender at 3 feet 80 dba Garbage disposal at 3 feet Noisy urban area, daytime Gas lawn mower, 100 feet 70 dba Vacuum cleaner at 10 feet Commercial area Heavy traffic at 300 feet 60 dba Normal speech at 3 feet Large business office Quiet urban daytime 50 dba Dishwasher in next room Quiet urban nighttime 40 dba Theater, large conference room Quiet suburban nighttime Quiet rural nighttime 0 dba Source: Technical Noise Supplement (TeNS), Caltrans, November 2009. 30 dba Library Bedroom at night, concert hall (background) 20 dba Broadcast/recording studio 10 dba 4

Regulatory Background The State of California, the City of Pleasant Hill, and the City of Walnut Creek establish guidelines, regulations, and policies designed to limit noise exposure at noise sensitive land uses. Appendix G of the State CEQA Guidelines, the City of Pleasant Hill s Noise Element of the General Plan, Zoning Ordinance, and Municipal Code, the City of Walnut Creek s Municipal Code present the following: State CEQA Guidelines. The California Environmental Quality Act (CEQA) contains guidelines to evaluate the significance of impacts attributable to a proposed project. CEQA asks whether the proposed project would result in: Exposure of persons to or generation of noise levels in excess of standards established in the local General Plan or Noise Ordinance, or applicable standards of other agencies? A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project? A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project? CEQA does not define what noise level increase would be considered substantial. Typically, project-generated noise level increases of 3 dba L dn or greater would be considered significant where exterior noise levels would exceed the normally acceptable noise level standard (60 dba L dn for residential land uses). Where noise levels would remain at or below the normally acceptable noise level standard with the project, noise level increases of 5 dba L dn or greater would be considered significant. City of Pleasant Hill General Plan. The Safety and Noise Element of the City of Pleasant Hill s 2003 General Plan identifies noise and land use compatibility standards for various land uses. The City's conditionally acceptable noise level objective for commercial land uses is 75 dba L dn and the City s acceptable noise level objective is 70 dba L dn. The plan also identifies policies to protect persons from noise that interferes with human activity or causes health problems. Safety and Noise Policy 7A. Require new development projects to be designed and constructed to meet acceptable noise level standards adopted by the City. Safety and Noise Policy 7B. Evaluate the noise impacts of development based on the potential for significant increases in noise levels, in addition to acceptability standards. The City of Pleasant Hill Zoning Ordinance. Ordinance No. 18.50.060 states that The following performance standards shall apply to all use classifications in all zoning districts: A. Noise. All uses and activities shall comply with the Pleasant Hill noise regulations, and no use 5

shall create ambient noise levels measured at the property line which exceed the standards in Schedule 18.50.060. Where noise is measured at the property line of abutting districts, the noise standard for the more restrictive district applies. (Pleasant Hill 2003). Table 3 presents the City s ambient base noise levels. TABLE 3 City of Pleasant Hill Zoning Ordinance SCHEDULE 18.50.060 MAXIMUM NOISE STANDARDS BY ZONING DISTRICT Zone of Property Receiving Noise Maximum Noise Level Ldn or CNEL, db R, NB Residential and Neighborhood Business Districts RB, C Commercial and Retail Business Districts 60 PAO Office District 65 LI Industrial District 70 PUD, PPD Planned Development/Precise Plan District The City of Pleasant Hill Municipal Code. In section 9.15.040 Special noise sources, the Municipal Code states the following regarding noise: H. Machinery, equipment, fans, and air-conditioning. It is unlawful for a person to operate machinery, equipment, a pump, fan, air-conditioning apparatus or similar mechanical device in a manner which creates noise, unless the noise is muffled and the device is equipped with a muffler sufficient to deaden the noise. 6 50 Study Required 1. Duration and timing. The noise standards above shall be modified as follows to account of the effects of time and duration on the impact of noise levels: a. In residential zones, the noise standard shall be five db lower between 10:00 p.m. and 7:00 a.m. b. Noise that is produced for more than a cumulative period of five minutes in any hour may exceed the standards above by five db. c. Noise that is produced for more than a cumulative period of one minute in any hour may exceed the standards above by 10 db. Based on a review of the applicable City of Pleasant Hill regulatory criteria, it was determined that the acoustical descriptors (CNEL or L dn ) cited in Section 18.50.060 of the Pleasant Hill Zoning Ordinance are incorrect. In our estimation, it is nearly impossible for residential zones to adhere to a 50 dba L dn noise limit at the property line when, in reality, very few areas of the City experience such a low L dn noise level. In our experience with other communities, a reasonable interpretation of the noise ordinance would indicate that the intended residential noise limit at the property line would be 50 dba L eq. It is also assumed that in noisier areas of the community, such as this particular site, that the noise standards are adjusted higher to reflect the ambient noise levels.

L. Construction of buildings and projects. 1. It is unlawful for a person within a residential land use district to operate or perform construction or repair work on a building, structure or project, or to operate a pile driver, steam shovel, pneumatic hammer, derrick, steam or electric hoist, or other construction-type device on city-recognized holidays as designated by city council resolution, and on Monday through Friday, prior to 7:30 a.m. and after 7:00 p.m. on each day and on Saturdays and Sundays, prior to 9:00 a.m. and after 6:00 p.m. The above prohibition does not apply to emergency work. City of Walnut Creek Municipal Code. In Title 4, Article 2 Noise, the Municipal Code states the following regarding noise: f. Construction or Repair of Buildings. The erection, construction, demolition, alteration or repair of any building, structure or residence that requires a permit, or the excavation of any earth, fill, streets or highways that requires a grading permit, other than between the hours of 7:00 a.m. and 6:00 p.m. on weekdays which are not holidays, or those precise hours of operation enumerated in individual building and grading permits. g. Maintenance Equipment. The use and operation of any noise-creating commercial or residential landscaping or home maintenance equipment or tools including, but not limited to, hammers, blowers, trimmers, mowers, chainsaws, power fans or any engine, the operation of which causes noise due to the explosion of operating gases or fluids, other than between the hours of 8:00 a.m. and 7:00 p.m. on weekdays and 9:00 a.m. and 7:00 p.m. on weekends and holidays. Existing Noise Environment The project site is located near the intersection of Oak Park Boulevard and North Main Street in Pleasant Hill, California and is bordered by single-family residences to the west, a mortuary to the south, commercial uses to the north, and North Main Street and Interstate 680 (I-680) to the east. The existing noise environment at the site and in the vicinity results primarily from traffic on I-680. A noise monitoring survey was conducted from May 20, 2010 to May 24, 2010 to quantify the existing noise environment at the project site and in the project vicinity. The noise monitoring survey in Pleasant Hill included one long-term noise measurement (LT-1), and three short-term measurements (ST-1 through ST-3), as shown in Figure 1. Long-term noise measurement LT-1 was located on the property line of homes located on Pleasant Court, approximately 240 feet from the center of North Main Street and about 12 feet above the ground. Noise levels measured at this site were primarily the result of traffic along I- 680. Hourly average noise levels typically ranged from 60 to 65 dba L eq during the day, and from 58 to 67 dba L eq at night. The calculated day-night average noise level at this location was 7

69 dba L dn during a weekday and ranged from 66 to 67 dba L dn on the weekend. Appendix 1 summarizes the data collected at the long-term measurement site. Short-term noise measurement ST-1 was approximately 240 feet from the center of North Main Street, at the property line of homes on Pleasant Court. The ten-minute average noise level was 57 dba L eq. Short-term noise measurement ST-2 was approximately 120 feet from the center of North Main Street, adjacent to the Oak Park Hills Chapel Mortuary. The ten-minute average noise level at this location was 59 dba L eq. Short-term noise measurement ST-3 was approximately 15 feet from the residential property line, at the end of Pleasant Court. This measurement location was shielded by a 6 foot masonry barrier. The ten-minute average noise level at this location was 54 dba L eq. Table 4 summarizes the results of these measurements. TABLE 4 Summary of Short-Term Noise Measurement Data Noise Measurement Location L max L (1) L (10) L (50) L (90) L eq L dn ST-1: ~240 feet from the center of North Main Street. 60 60 59 57 56 57 61 (5/20/2010, 14:30-14:40) ST-2: ~120 feet from the center of North Main Street, adjacent to the 66 64 61 59 57 59 63 Mortuary. (5/24/2010, 11:50-12:00) ST-3: ~15 feet from the residential property line, shielded by a 6 foot noise barrier. (5/24/2010, 12:10-12:20) 59 57 55 54 53 54 60 Note: L dn approximated by correlating to corresponding period at long-term site. An additional noise monitoring survey was conducted on May 24, 2010 at an existing In-N-Out Burger restaurant located near the intersection of Blossom Hill Road and Santa Teresa Boulevard in San Jose, California. The purpose of this noise survey was to quantify existing noise levels resulting from typical site operations at an equivalent restaurant. Noise measurements were conducted in the parking lot directly adjacent to the drive-through speaker for a period of 30 minutes, from 3:20 p.m. to 3:50 p.m. During that period approximately 25 separate orders were measured at a distance of 20 feet from the speaker. Typical noises associated with the drivethrough included amplified speech emanating from the speaker, idling cars, cars circulating along the drive-through aisle, and less frequently, engines starting. During busy periods, the restaurant prefers to place an attendant near the site entrance to take orders, and the intercom system is not used. Customers placing orders using the intercom system typically resulted in noise levels of about 62 to 67 dba L max. Vehicle circulation and cars idling typically generated maximum noise levels of 56-58 dba L max. Occasionally a particularly loud vehicle (diesel pickup truck, or loud exhaust) traveled through the drive thru and generated maximum noise levels of about 70 to 72 dba L max. Drive thru operations generated an average noise of 63 dba L eq at a distance of 20 feet. 8

Figure 1. Noise Measurement Locations and Site Vicinity Nearest Residences ST-3 LT-1 Proposed Parking Area North Main Street I-680 ST-1 Proposed Restaurant Site ST-2 Oak Park Hills Chapel 9

CEQA Assessment Significance Criteria Appendix G of the CEQA Guidelines states that a project would normally be considered to have a significant impact if noise levels conflict with adopted environmental standards or plans, or if noise levels generated by the project would substantially increase existing noise levels at noisesensitive receivers on a permanent or temporary basis. A substantial permanent noise increase would occur if the noise level increase resulting from the project is 3 dba L dn or greater, with a future noise level of 60 dba L dn or greater. Construction noise is evaluated somewhat differently than operational noise, as its effects are temporary. When construction activities are predicted to cause prolonged interference (greater than one construction season) with normal activities at noise-sensitive receiver locations, generate noise levels in excess of 60 dba L eq, and exceed ambient noise levels by 5 dba L eq or more, the impact would be considered significant. Impact: Noise and Land Use Compatibility. Noise levels on the site would not exceed those considered conditionally acceptable for the intended use according to the City of Pleasant Hill s Noise Element of the General Plan. This is a less-thansignificant impact. The future noise environment at the site would continue to result primarily from vehicular traffic along I-680. Future noise levels are calculated to be about 75 dba L dn at the facade of the restaurant building proposed along North Main Street (approximately 100 feet from the center of the roadway). The City of Pleasant Hill considers office buildings, business commercial, and professional land uses (category most similar to a fast-food restaurant) conditionally acceptable in noise environments up of 75 dba L dn. As such, the proposed land use would be compatible with the noise environment expected at the site. Mitigation: Impact: None Operational Noise. The operation of the project would increase ambient noise levels at nearby noise-sensitive land uses. This is a significant noise impact. Mechanical Equipment Noise Mechanical equipment associated with the restaurant will likely include heating, ventilating, airconditioning, and refrigeration units that could be located on the roof of the building or in unshielded areas. Residential uses, at their nearest point, would be about 70 feet from the proposed building. The noise from this equipment, if not designed and located correctly, could exceed the City s Municipal noise standard at the adjacent residential property line. Trash Compactor Noise The trash and recycling enclosure will be located in the loading dock and drive-through area approximately 80 feet from the nearest noise-sensitive residential outdoor use area with the wall enclosure positioned between the compactor and the residences. Because of its placement, noise 10

generated by the trash compactor will be attenuated by the wall surrounding the loading dock. Additionally, there is an 8 foot screen wall proposed along the western property line of the project site. Trash compactors typically generate maximum noise levels of 52 to 57 dba at 80 feet, depending on the power rating and enclosure characteristics. It is not known at this time what the specific characteristics are for the compactor to be used. Noise levels resulting from the trash compactor, taking into account the shielding provided by the trash enclosure wall and the 8 foot property screen wall, are calculated to be approximately 32 to 37 dba at the nearest singlefamily residential land uses. The operation of the trash compactor would generally be inaudible and will not measurably increase the day-night average noise levels at nearby sensitive land uses. Loading Dock Noise Truck deliveries can result in intermittent noises during loading/unloading activities and circulation. The site plan indicates that the loading area would be near the drive-through, about 80 feet from the residential outdoor use areas located to the west. Loading dock noise (from unloading of products) would be shielded by the 8 foot screen wall that runs along the western perimeter of the site. Intermittent noises emanating from the loading dock would be 57 dba and less than ambient noise levels at the adjacent residences. Noise generated by intermittent loading/unloading activities would not substantially increase hourly average or daily-average noise levels at the nearest noise-sensitive receptors. It is assumed that site access would be from North Main Street or Oak Park Blvd, which could bring delivery trucks within about 50 feet of the residences. Trucks circulating through the site would generate typical maximum noise levels of about 65 to 70 dba during passby when measured at 50 feet. Accounting for noise propagation due to distance and shielding provided by the 8 foot noise barrier, maximum noise levels would be about 50 to 55 dba L max at the closest residential outdoor use area. These noise levels would generally be lower than existing maximum noise levels at the site resulting from I-680, and would therefore be in compliance with the City s Municipal Code standards. Parking Lot and Outdoor Patio Noise The proposed surface parking lot and outdoor dining patio will be located on the northern portion of the project site bordered by residential land uses to the west. The major noise sources attributed to parking lot activities is the sound of vehicles as they drive by, noise generated when vehicles start their engines, door slams and the occasional sound of car alarms. Sounds of voices generally produce less noise. Based on data contained in I&R files, typical parking lot activities generate maximum noise levels of 50 to 60 dba L max when measured at 50 feet from the source. Car alarms generate maximum noise levels of 63 to 70 dba L max at 50 feet. The hourly average noise level resulting from all these noise-generating activities in a small parking lot would reach 40 dba L eq at a distance of 50 feet from the parking area. Residential units at the end of Pleasant Court (approximately 15 feet from active parking areas, at their nearest point) will experience hourly average noise levels of 50 dba L eq and would not exceed the ambient base noise levels currently experienced at the site. Maximum noise levels would range from about 60 to 70 dba L max as a result of typical activities and could reach 80 dba L max when car alarms are sounded. Parking lot activities could result in intermittent, loud noises on adjoining residential 11

properties, but would not normally produce noise levels louder than existing traffic along North Main Street and I-680. Outdoor patio seating will be located on the northern and eastern portion of the restaurant building. The major noise sources attributed to outdoor patio seating is the sound of voices while people are eating. Sounds of voices generally produce less noise than that produced by other parking lot activities (vehicle engine starts, door slams, and car alarms). Outdoor patio activities could result in intermittent, audible noises on adjoining residential properties, but would not normally produce noise levels louder than existing traffic along North Main Street and I-680. The project plans indicate that a screen wall is proposed along the western boundary of the project site. Construction of an 8 foot barrier along the common property line would attenuate noise levels generated from vehicle engines, alarms, and horns at the adjacent residential receivers. This wall would effectively reduce noise from parking lot activities, and in addition, serve to reduce traffic noise from North Main Street and I-680. Activities occurring outside the restaurant near the parking lot would result in hourly average noise levels of 40 dba L eq or less in the outdoor use areas of adjacent residential uses. Drive-Through Noise Currently, most In-N-Out restaurants are open from 10:30 a.m. to 1:00 a.m. Sunday through Thursday and from 10:30 a.m. to 1:30 a.m. on Friday and Saturday. The proposed drive-through will be located on the western and southern perimeter of the project site, adjacent to residences along Pleasant Court and the Oak Park Hills Chapel. The major noise sources attributed to the drive-through include amplified speech emanating from the speaker, idling cars, cars circulating along the drive-through aisle, and less frequently, engines starting. Based on the measurements conducted at the existing In-N-Out Burger in San Jose, the drivethrough speaker and patron voices would result in maximum sound levels ranging from 58 to 65 dba L max at the residential property line (approximately 30 feet from the drive-through speaker). Considering the attenuation provided by the property line screen wall at the residences behind the project site, the noise level produced by the drive-through speaker and patron voices would result in maximum noise levels ranging from 45 to 50 dba in the rear yard of the residences along Pleasant Court. The drive-through lane will also result in noise from vehicles idling while within the drivethrough lane. Idling vehicles typically produce noise levels of between 52 to 54 dba L max at 30 feet from the source. Considering the attenuation received from the property line noise barrier at the residences west of the project site, the noise level produced by vehicles idling while in the drive-through lane would result in maximum noise levels of between 39 and 41 dba in the rear yards of the nearest residences. Maximum noise generated by restaurant activities would be audible during periods with low ambient traffic noise or during occasional loud activities such as circulating vehicles with loud stereos or engines. Noise levels generated by loud vehicles on the site would be similar to noise 12

levels generated by circulation of the same or similar vehicles on the roadway network and along North Main Street. Maximum noise levels resulting from the drive-through would fall below the Walnut Creek regulatory criteria and would typically be lower than maximum noise levels generated by traffic on North Main Street and on I-680. Although the operation of the restaurant will, at times, create intermittent, audible noises at adjacent residences, these noises will not measurably (less than 1 dba L dn ) increase existing L dn noise levels experienced in the outdoor use areas of nearby residences. The existing noise environment resulting from traffic from I-680 will continue to be the dominant noise source. Mitigation: The following mitigation measure shall be included in the project to reduce the impact to a less-than-significant level: Mechanical equipment shall be designed to minimize impacts on surrounding uses, particularly residences located west of the site. This can be accomplished by locating noise-generating equipment on the easternmost portion of the building, adjacent to North Main Street or by providing acoustical shielding. If rooftop-mounted equipment is used, it should be shielded from the adjacent residential land uses by rooftop screens or perimeter parapet walls. An acoustical specialist should review the mechanical equipment plans prior to construction to confirm the City s Municipal Code standards would be met at the residential property line. Impact: Project-Generated Street Traffic Noise. The proposed project will not substantially increase traffic noise levels along roadways in the project vicinity. This is a less-than-significant impact. Project traffic data was reviewed to calculate the relative change in noise levels expected with the operation of the project. The project would result in an additional 188 peak hour vehicle trips. The majority of trips would be along North Main Street. Very few vehicles would access the site from Oak Pak Boulevard. Vehicular traffic generated by the project would not increase noise levels substantially because the project traffic makes up a small percentage of the total traffic along area roadways. Vehicular traffic noise levels are not expected to increase measurably above existing levels as a result of the project (increase would be less than 1 dba L dn ). Mitigation: Impact: None Required. Construction Noise. Project-generated construction noise would temporarily increase noise levels at adjacent residential receivers. This is a less-thansignificant impact. The construction of the project would generate noise and would temporarily increase noise levels at adjacent residential receivers. Noise impacts resulting from construction depend on the noise generated by various pieces of construction equipment operating on site, the timing and duration of noise generating activities, the presence of intervening terrain or noise barriers, and the distance between construction noise sources and noise sensitive receptors. Where noise from construction activities exceeds 60 dba L eq and exceeds the ambient noise environment by at 13

least 5 dba L eq at noise-sensitive uses in the project vicinity for a period of more than one construction season, the impact would be considered significant. Construction activities generate considerable amounts of noise, especially during demolition activities and when project infrastructure improvements are made with the use of heavy construction equipment. Table 5 depicts the range of A-weighted noise levels generated by specific pieces of construction equipment at a distance of 50 feet. Table 6 presents typical ranges in hourly average noise levels at a distance of 50 feet generated different phases of construction. The highest maximum noise levels generated by project construction would typically range from about 90 to 95 dba at a distance of 50 feet from the noise source. Typical hourly average construction generated noise levels are about 78 dba to 89 dba measured at a distance of 50 feet from the center of the site during busy construction periods (e.g., earth moving equipment, impact tools, etc.). Construction generated noise levels drop off at a rate of about 6 dba per doubling of distance between the source and receptor. Shielding by buildings or terrain often result in lower construction noise levels at distant receptors. Construction noise impacts primarily result when construction activities occur during noisesensitive times of the day (early morning, evening, or nighttime hours), the construction occurs in areas immediately adjoining noise sensitive land uses, or when construction durations last over extended periods of time. Limiting the hours when construction can occur to daytime hours is often a simple method to reduce the potential for noise impacts. In areas immediately adjacent to construction, controls such as constructing temporary noise barriers and utilizing quiet construction equipment can also reduce the potential for noise impacts. It is anticipated that the project would be constructed over a period of less than one construction season (approximately 4 months). Construction phases would include grading of the site, placement of underground utilities, paving of the parking lot, construction of the foundation, columns, components, framing and exterior wall envelop. Project construction would be expected to generate worst-case hourly average noise levels of about 78 dba to 89 dba L eq at the nearest noise-sensitive receivers when construction occurs at the perimeter of the site adjoining the residences to the south. Given the proximity of the singlefamily residences, construction noise levels would generally exceed 60 dba L eq and the ambient noise environment by at least 5 dba L eq when activities are occurring outside during noisy construction phases. Noise generated by grading, infrastructure improvements, parking lot construction, and the construction of restaurant would not be expected to exceed ambient noise levels at receivers to the west by more than 5 dba L eq for a period of greater than one construction season. Significant noise impacts do not normally occur when standard construction noise control measures are enforces at the project site and when the duration of the noise generating construction period at a particular receiver or group of receivers is limited to one construction season (typically one year) or less. Reasonable regulation of the hours of construction, as well as regulation of the arrival and operation of heavy equipment and the delivery of construction material, are necessary to protect the health and safety of persons, promote the general welfare of the community, and maintain the quality of life. 14

Although the noise impact is less-than-significant, the following measures should be included in the project to reduce construction noise levels as low as feasible: Noise-generating activities at the construction site or in areas adjacent to the construction site associated with the project in any way should be restricted to the hours of 8:00 a.m. to 7:00 p.m. on weekdays and 9:00 a.m. to 7:00 p.m. on weekends. Equip all internal combustion engine driven equipment with intake and exhaust mufflers that are in good condition and appropriate for the equipment. Locate stationary noise generating equipment as far as possible from sensitive receptors when sensitive receptors adjoin or are near a construction project area. Construct temporary noise barriers to screen stationary noise generating equipment when located near adjoining sensitive land uses. Temporary noise barriers could reduce construction levels by 5 dba. Utilize "quiet" air compressors and other stationery noise sources where technology exists. The contractor shall prepare a detailed construction plan identifying the schedule for major noise-generating construction activities. The construction plan shall identify a procedure for coordination with the adjacent noise sensitive facilities so that construction activities can be scheduled to minimize noise disturbance. Designate a "disturbance coordinator" who would be responsible for responding to any local complaints about construction noise. The disturbance coordinator will determine the cause of the noise complaint (e.g., starting too early, bad muffler, etc.) and will require that reasonable measures warranted to correct the problem be implemented. Conspicuously post a telephone number for the disturbance coordinator at the construction site and include it in the notice sent to neighbors regarding the construction schedule. Control noise from construction workers radios to a point where they are not audible at existing residences bordering the project site. With the incorporation of these standard construction noise control best management practices, the noise impact resulting from project construction would be considered less-than-significant. Mitigation Measures: No additional measures are required. 15

TABLE 5 Noise Level Range of Typical Construction Equipment A-Weighted Noise Level (db) at 50 Feet 60 70 80 90 100 110 Earth Moving: Compactors (Rollers) Front Loaders Backhoes Bulldozers Scrapers, Graders Pavers Trucks Materials Handling: Concrete Mixers Concrete Pumps Cranes (Movable) Cranes (Derrick) Stationary: Pumps Generators Compressors Impact Equipment: Pneumatic Wrenches Jackhammers & Rock Drill Pile Drivers (Peak) Others: Vibrators Saws Source: Handbook of Noise Control, Cyril M. Harris, 1979 16

TABLE 6 Noise Levels by Construction Phase Typical Ranges of Energy Equivalent Noise Levels at 50 Feet, L eq in dba, at Construction Sites Domestic Housing Office Building, Hotel, Hospital, School, Public Works Industrial Parking Garage, Religious Amusement & Recreations, Store, Service Station Public Works Roads & Highways, Sewers, and Trenches I II I II I II I II Ground Clearing 83 83 84 84 84 83 84 84 Excavation 88 75 89 79 89 71 88 78 Foundations 81 81 78 78 77 77 88 88 Erection 81 65 87 75 84 72 79 78 Finishing 88 72 89 75 89 74 84 84 I - All pertinent equipment present at site. II - Minimum required equipment present at site. Source: U.S.E.P.A., Legal Compilation on Noise, Vol. 1, p. 2-104, 1973. 17

Appendix 1: Daily Trend in Noise Levels Noise Levels at LT-1 At Property Line of Homes on Pleasant Court Thursday May 20, 2010 90 85 80 75 Noise Level (dba) 70 65 60 55 Leq L(1) L(10) L(50) L(90) 50 45 40 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 Hour Beginning Noise Levels at LT-1 At Property Line of Homes on Pleasant Court Friday May 21, 2010 90 85 80 75 Noise Level (dba) 70 65 60 55 50 Leq L(1) L(10) L(50) L(90) Ldn = 69 dba 45 40 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 Hour Beginning 18

Noise Levels at LT-1 At Property Line of Homes on Pleasant Court Saturday May 22, 2010 90 85 80 75 Noise Level (dba) 70 65 60 55 50 Leq L(1) L(10) L(50) L(90) Ldn = 67 dba 45 40 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 Hour Beginning Noise Levels at LT-1 At Property Line of Homes on Pleasant Court Sunday May 23, 2010 90 85 80 75 Noise Level (dba) 70 65 60 55 50 Leq L(1) L(10) L(50) L(90) Ldn = 66 dba 45 40 0:00 2:00 4:00 6:00 8:00 10:00 12:00 14:00 16:00 18:00 20:00 22:00 Hour Beginning 19