5.5 NOISE SUMMARY INTRODUCTION AND METHODOLOGY

Transcription

1 5.5 NOISE SUMMARY This section of the environmental impact report (EIR) addresses the potential impacts that could result from the Lyons Avenue At-Grade Rail Crossing project (proposed project). Noise prediction modeling conducted in this analysis utilized the Federal Highway Administration (FHWA) Highway Noise Prediction Model (FHWA-RD ). Modeling data referenced in this analysis is provided in Appendix 5.5. Construction of the proposed project would require site preparation, grading, and the construction of the crossing. Each of these construction activities typically involves the use of heavy-duty equipment, all of which could expose off-site residents and other noise sensitive receptors to temporary noise impacts. Section of the City of Santa Clarita Noise Ordinance prohibits construction operations to occur within 300 feet of residentially zoned properties during early morning, evening, and nighttime hours, and all hours on Sundays and major holidays. Nonetheless, project construction noise would intermittently exceed the noise limits adopted for residential zones in Section of the City s Noise Ordinance. Construction would result in vibration impacts that would be less than the Federal Transit Administration s (FTA) published gu idelines for assessing the impacts of groundborne vibration associated with construction activities. After the project is built out, operational traffic using the Lyons Avenue at-grade rail crossing would generate noise. However, the traffic increase due to the proposed project would have a less than significant impact on noise-sensitive receptors located adjacent to or near to affected roadways. No significant unavoidable mobile source noise impacts would occur. Traffic associated with the proposed project would also contribute to cumulative noise increases in the region. Future traffic on the proposed roadway extensions through the site and on existing local roadways would generate noise in the region. However, the traffic increase due to the proposed project during the cumulative (2030) year would have a less than significant impact on noise-sensitive receptors located adjacent to or near to the affected roadways. No significant unavoidable mobile source cumulative noise impacts would occur. INTRODUCTION AND METHODOLOGY This noise impact assessment evaluates the potential for significant noise impacts resulting from the proposed project. The proposed project is located in the Newhall area of the City of Santa Clarita, east of the Santa Susana Mountains in northern Los Angeles County, California. The proposed project analyzed in this Stage I EIR focuses on a request to create a new at-grade rail crossing of the Los Angeles County Metropolitan Transportation Authority (Metro) railroad tracks at the terminus of Lyons Avenue at Railroad Avenue and closure of 13 th Street at-grade rail crossing upon completion of the future extension of Dockweiler Drive as a part of the North Newhall Specific Plan (NNSP). The NNSP project/stage II EIR Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

2 would consist of the proposed conceptual development and implementation of a larger Specific Plan for the entire 213-acre project site. This Stage I EIR does not allow for approval of the future extension of Dockweiler Drive or approval of the Stage II NNSP with its associated development potential. However, assumptions about the eventual extension of this roadway and the implementation of the NNSP have been incorporated into the traffic analysis for the proposed project and are discussed generally in this Stage I EIR. This assessment presents the fundamentals of environmental noise, describes regulatory criteria that would be applicable to the project, summarizes existing noise conditions at noise-sensitive receivers in the vicinity of the project, and discusses the predicted changes in noise levels resulting from the project. Noise increases are evaluated in the impact assessment with respect to significance criteria developed for the project, and noise reduction measures are presented to reduce the effects of project-generated noise. This section of the EIR has been prepared in accordance with California Department of Transportation (Caltrans) policies to address traffic noise impacts. The analysis also has been prepared to comply with the California Environmental Quality Act (CEQA), the City of Santa Clarita General Plan, and local noise ordinances. Noise prediction modeling conducted in this analysis utilized the FHWA Highway Noise Prediction Model (FHWA-RD ). Modeling data referenced in this analysis is provided in Appendix 5.5 of this EIR. Fundamentals of Environmental Noise Noise is usually defined as unwanted sound. It is an undesirable by-product of society s normal day-to-day activities. Sound becomes unwanted when it interferes with normal activities, when it causes actual physical harm, and/or when it has adverse effects on health. The definition of noise as unwanted sound implies that it has an adverse effect on people and their environment. Decibels and Frequency Weighted Metrics Noise is measured on a logarithmic scale of sound pressure level known as a decibel (db). The human ear does not respond uniformly to sounds at all frequencies; for example, it is less sensitive to low and high frequencies than to medium frequencies that more closely correspond with human speech. In response to the sensitivity of the human ear to different frequencies, the A-weighted noise level (or scale), which corresponds better with people s subjective judgment of sound levels, has been developed. This A-weighted sound level, referenced in units of db(a), is measured on a logarithmic scale such that a doubling of sound energy results in a 3 db(a) increase in noise level. In general, changes in a community Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

3 noise level of less than 3 db(a) are not typically noticed by the human ear. 1 Changes from 3 to 5 db(a) may be noticed by some individuals who are extremely sensitive to changes in noise. A greater than 5 db(a) increase is readily noticeable, while the human ear perceives a 10 db(a) increase in sound level to be a doubling of sound. In order to simplify the measurement and computation of sound loudness levels, frequency weighted networks have obtained wide acceptance. The A-weighting (db(a)) scale has become the most prominent of these scales and is widely used in community noise analysis. Its advantages are that it has shown good correlation with community response and is easily measured. The metrics used in this study are all based upon the db(a) scale. Single Event Noise Exposure Level Single Event Noise Exposure Level (SENEL) or Sound Exposure Level (SEL) is computed from db(a) sound levels, and is used to quantify the total noise associated with a single event, such as an aircraft overflight or a train pass-by. Within Figure 5.5-1, Single and Cumulative Noise Metric Definitions, the shaded area, or the area within 10 db of the maximum noise level, is the area from which the SENEL is computed. The SENEL value is the integration of all the acoustic energy contained within the event. Speech and sleep interference research can be assessed relative to SENEL data. Maximum Noise Level Maximum Noise Level or Lmax is the highest noise level reached during a noise event. For example, as a truck approaches, the sound of the truck begins to rise above ambient noise levels. The closer the truck gets the louder it is until the truck is at its closest point. Then as the truck passes, the sound level decreases until it returns to ambient levels. Such a history of a truck pass-by is plotted in Figure Itis this metric to which people generally instantaneously respond when a loud vehicle like a truck or motorcycle passes by. The SENEL metric takes into account the maximum noise level of the event and the duration of the event. In addition, cumulative noise metrics, which are discussed below, can be computed from SENEL data. Equivalent Noise Level Equivalent Noise Level (Leq) is the sound level corresponding to a steady-state A-weighted sound level containing the same total energy as several SEL events during a given sample period. Leq is the energy average noise level during the period of the sample. It is based on the observation that the potential for 1 U.S. Department of Transportation, Federal Highway Administration, Highway Noise Fundamentals, (1980), 81. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

4 noise annoyance is dependent on the total acoustical energy content of the noise. This is graphically illustrated in the middle graph of Figure Leq can be measured for any period, but is typically measured for 15 minutes, 1 hour or 24-hours. Leq for 1 hour is called Hourly Noise Level (HNL) in the California Airport Noise Regulations and is used to develop Community Noise Equivalent Level (CNEL) values for aircraft operations. Community Noise Equivalent Level Community Noise Equivalent Level, or CNEL, is a 24-hour, time-weighted energy average noise level based on the A-weighted decibel. It is a measure of the overall noise experienced during an entire day. The term time-weighted refers to the penalties attached to noise events occurring during certain sensitive periods. In the CNEL scale, 5 db(a) are added to measured noise levels occurring between the hours of 7:00 PM and 10:00 PM. Ten db(a) are added to measured noise levels occurring between the hours of 10:00 PM to 7:00 AM. These decibel adjustments are an attempt to account for the higher sensitivity to noise in the evening and nighttime hours, and the expected lower ambient noise levels during these periods. CNEL is graphically illustrated in the bottom of Figure Examples of various noise environments in terms of CNEL are presented in Figure 5.5-2, Examples of Typical Outdoor CNEL Levels. L(%), Lmax, and Lmin L(%), Lmax, andlmin are statistical methods to account for variance in noise levels throughout a given measurement period. L(%) is a way of expressing the noise level exceeded for a percentage of time in a given measurement period. For example, 5 minutes is 25 percent of 20 minutes, L(25) is the noise level that is equal to or exceeded for 5 minutes in a 20 minute measurement period. L(%) is typically used in noise ordinances and municipal codes. Lmax represents the loudest measured noise level. It only occurs for a fraction of a second; all other measured noise levels are less than Lmax. Lmin represents the quietest noise level during a noise measurement with all other measured noise levels greater than Lmin. Sound Rating Scales Various rating scales approximate the human subjective assessment to the "loudness" or "noisiness" of a sound. Noise metrics have been developed to account for additional parameters, such as duration and cumulative effect of multiple events. Noise metrics are categorized as single event metrics and cumulative metrics, as summarized below. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

5 SOURCE: Mestre Greve Associates, One Valley One Vision Noise Element of the General Plan - February 2009 FIGURE Single and Cumulative Noise Metric Definitions /10

6 SOURCE: Mestre Greve Associates, One Valley One Vision Noise Element of the General Plan - February 2009 FIGURE Examples of Typical Outdoor CNEL Levels /10

7 Single Event Metrics Single event metrics describe the noise from individual events, such as one aircraft flyover or a large truck passing by. Cumulative Metrics Cumulative metrics describe noise in terms of the total noise exposure throughout the day, and incorporates the loudness of the noise, the duration of the noise, the total number of noise events and the time of day these events occur into one single number rating scale. Adverse Effects of Noise Exposure Noise is known to have several adverse effects on humans, which has led to laws and standards being set to protect public health and safety, and to ensure compatibility between land uses and activities. Adverse effects of noise on people include hearing loss, communication interference, sleep interference, physiological responses, and annoyance. Each of these potential noise impacts on people are briefly discussed below. Hearing Loss Hearing loss is generally not a community noise concern, even very near a major airport or a major freeway. The potential for noise induced hearing loss is more commonly associated with occupational noise exposures in heavy industry, very noisy work environments with long term exposure, or certain very loud recreational activities, such as target shooting or motorcycle or car racing. The Occupational Safety and Health Administration (OSHA) identifies a noise exposure limit of 90 db(a) for 8 hours per day to protect from hearing loss (higher limits are allowed for shorter duration exposures). Noise levels in neighborhoods, even in very noisy neighborhoods, are not sufficiently loud to cause hearing loss. Communication Interference Communication interference is one of the primary concerns in environmental noise problems. Communication interference includes speech interference and interference with activities such as watching television. Noise can also interfere with communications within school classrooms, as well as classroom activities. Normal conversational speech is in the range of 60 to 65 db(a) and any noise in this range or louder may interfere with speech. There are specific methods of describing speech interference as a function of distance between speaker and listener and voice level. Figure 5.5-3, Speech Interference and Noise Levels, shows the relation of quality of speech communication with respect to various noise levels. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

8 Sleep Interference Noise can make it difficult to fall asleep, create momentary disturbances of natural sleep patterns by causing shifts from deep to lighter stages and cause awakening. Noise may even cause awakening that a person may or may not be able to recall. Physiological Responses Physiological responses are those measurable effects of noise on people that are realized as changes in pulse rate, blood pressure, etc. Studies to determine whether exposure to high noise levels can adversely affect human health have concluded that, while a relationship between noise and health effects seems plausible, there is no empirical evidence of the relationship. Annoyance Annoyance is the most difficult of all noise responses to describe. Annoyance is a very individual characteristic and can vary widely from person to person. Noise that one person considers tolerable can be unbearable to another of equal hearing capability. The level of annoyance depends both on the characteristics of the noise (including loudness, frequency, time, and duration), and how much activity interference (such as speech interference and sleep interference) results from the noise. However, the level of annoyance is also a function of the attitude of the receiver. Personal sensitivity to noise varies widely. It has been estimated that 2 to 10 percent of the population is highly susceptible to annoyance from any noise not of their own making, while approximately 20 percent are unaffected by noise. Attitudes may also be affected by the relationship between the person affected and the source of noise, and whether attempts have been made to abate the noise. Noise Attenuation Noise sources occur in two forms: (1) point sources, such as stationary equipment or individual motor vehicles; and (2) line sources, such as a roadway with a large number of point sources (motor vehicles). Sound generated by a point source typically diminishes (attenuates) at a rate of 6 db(a) for each doubling of distance from the source to the receptor at acoustically hard sites and 7.5 db(a) at acoustically soft sites. 2 For example, a 60 db(a) noise level measured at 50 feet from a point source at an acoustically hard 2 U.S. Department of Transportation, Federal Highway Administration, Highway Noise Fundamentals, (1980) 97. Examples of "hard" or reflective sites include asphalt, concrete, and hard and sparsely vegetated soils. Examples of acoustically "soft" or absorptive sites include soft, sand, plowed farmland, grass, crops, heavy ground cover, etc. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

9 Legend: dba = A weighted noise level PSIL = Preferred speech interference level SIL = Speech interference level SOURCE: Mestre Greve Associates, One Valley One Vision Noise Element of the General Plan - February 2009 FIGURE Speech Interference and Noise Levels /10

10 site would be 54 db(a) at 100 feet from the source and 48 db(a) at 200 feet from the source. Sound generated by a line source typically attenuates at a rate of 3 db(a) and 4.5 db(a) per doubling of distance from the source to the receptor for hard and soft sites, respectively. 3 Sound levels can also be attenuated by man-made or natural barriers (e.g., sound walls, berms, ridges), as well as elevational differences, as illustrated in Figure 5.5-4, Noise Attenuation by Barriers and Elevational Differences. Solid walls and berms may reduce noise levels by 5 to 10 db(a) depending on their height and distance relative to the noise source and the noise receptor. 4 Sound levels may also be attenuated 3 to 5 db(a) by a first row of buildings and 1.5 db(a) for each additional row of buildings. 5 The minimum noise attenuation provided by typical structures in California is provided in Table 5.5-1, Outside to Inside Noise Attenuation. Table Outside to Inside Noise Attenuation (db(a)) Open Closed Building Type Windows Windows Hotels/Motels Residences Schools Churches Hospitals/Convalescent Homes Offices Theaters Source: Gordon, C.G., W.J. Galloway, B.A. Kugler, and D.L. Nelson. NCHRP Report 117: Highway Noise: A Design Guide for Highway Engineers. Washington, D.C.: Transportation Research Board, National Research Council, Fundamentals of Environmental Vibration Vibration is a form of noise with energy carried through structures and the earth, whereas noise is simply carried through the air. Thus, vibration is generally felt rather than heard. Some vibration effects can be caused by noise, e.g., the rattling of windows from passing trucks. Typically, ground-borne vibration 3 U.S. Department of Transportation, Federal Highway Administration, Highway Noise Fundamentals, (1980) U.S. Department of Transportation, Federal Highway Administration, Highway Noise Mitigation, (1980) T. M. Barry and J. A. Reagan, FHWA Highway Traffic Noise Prediction Model, (U.S. Department of Transportation, Federal Highway Administration, Office of Research, Office of Environmental Policy, 1978), NTIS, FHWA-RD , 33. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

11 generated by manmade activities attenuates rapidly as distance from the source of the vibration increases. The ground motion caused by vibration is measured as peak particle velocity (PPV) in inches per second. PPV is the speed at which a particle of earth moves and is expressed in units of inches per second. Vibration also is measured as the root mean square amplitude of a motion over a 1-second period. For convenience, the logarithmic decibel scale is used to describe vibration velocity level relative to a reference level of 10-6 inches per second and is expressed as vibration decibels (VdB). The vibration velocity level threshold of perception for humans is approximately 65 VdB. 6 Avibration velocity of 75 VdB is considered the approximate dividing line between barely and distinctly perceptible levels for many people. 7 Most perceptible indoor vibration is caused by sources within buildings such as operation of mechanical equipment, movement of people, or the slamming of doors. Typical outdoor sources of perceptible ground-borne vibration include construction equipment, steel-wheeled trains, and traffic on rough roads. If a roadway is smooth, the ground-borne vibration from traffic is barely perceptible. 8 The range of interest is from approximately 50 VdB, which is the typical background vibration velocity, to 100 VdB, which is the general threshold where minor damage can occur in fragile buildings. Figure 5.5-5, Typical Levels of Ground-Borne Vibration, identifies the typical ground-borne vibration levels in VdB and human response to different levels of vibration. Project Study Area The project study area includes the roadways and intersections near the project site and those locations where project-generated traffic could be reasonably expected to cause noise impacts. The study area was determined based on the City of Santa Clarita s Traffic Model and the Intersection Capacity Utilization (ICU) methodology as well as input from City staff. The project study area is located in the Downtown Newhall Specific Plan (DNSP) area and the proposed NNSP area. The Lyons Avenue component is bound to the north by 12 th Street, to the east by Newhall Creek, to the south by 9 th Street, and to the west by Main Street. 6 U.S. Department of Transportation, Federal Transit Administration, Office of Planning and Environment, Transit Noise and Vibration Impact Assessment (FTA-VA ), (2006) U.S. Department of Transportation, Transit Noise and Vibration Impact Assessment, 7-6 and U.S. Department of Transportation, Transit Noise and Vibration Impact Assessment, 7-9. Rubber tires and suspension systems provide vibration insulation. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

12 Source 8' Deflected Noise Roadway Barrier Line-of-Sight Receptor "Barrier Effect" Resulting from Differences in Elevation. Source Deflected Noise Line-of-Sight Receptor 8' Roadway Barrier "Barrier Effect" Resulting from Typical Soundwall. SOURCE: Impact Sciences, Inc. October 2004 FIGURE Noise Attenuation by Barriers and Elevational Differences /10

13 HUMAN/STRUCTURAL RESPONSE PPV AMPLITUDE IN INCHES PER SECOND 1 VELOCITY LEVEL IN VdB RMS VELOCITY AMPLITUDE IN INCHES/SECOND 2 TYPICAL SOURCES 50 FEET FROM SOURCE THRESHOLD, MINOR COSMETIC DAMAGE TO FRAGILE BUILDINGS BLASTING FROM CONSTRUCTION PROJECTS 0 DIFFICULTY WITH TASKS SUCH AS READING A VDT SCREEN BULLDOZER AND OTHER HEAVY-TRACKED CONSTRUCTION EQUIPMENT RESIDENTIAL ANNOYANCE, INFREQUENT EVENTS (E.G., COMMUTER RAIL) COMMUTER RAIL, UPPER RANGE RAPID TRANSIT, UPPER RANGE RESIDENTIAL ANNOYANCE, FREQUENT EVENTS (E.G., RAPID TRANSIT) COMMUTER RAIL, TYPICAL BUS OR TRUCK OVER BUMP RAPID TRANSIT, TYPICAL LIMIT FOR VIBRATION-SENSITIVE EQUIPMENT APPROXIMATE THRESHOLD FOR HUMAN PERCEPTION OF VIBRATION BUS OR TRUCK, TYPICAL AVERAGE RESIDENCE WITHOUT STEREO PLAYING AVERAGE WHISPER TYPICAL GROUND VIBRATION 1 2 PPV is typically a factor 1.7 to 6 times greater than RMS vibration velocity. A factor of 4 was used to calculate noise levels. Vibration levels in terms of velocity levels are defined as: V=20 x log 10 (a/r) V=velocity levels in decibels a=rms velocity amplitude r=reference amplitude (accepted reference quantities for vibration velocity are 1 x 10-6 inches/second in the United States) FIGURE Typical Levels of Ground-Borne Vibration /10

14 The 13 th Street component of the proposed project is bound to the north by vacant, undeveloped land, to the east by commercial buildings, to the south by Railroad Avenue, and to the west by commercial buildings and Railroad Avenue. Potential future extensions through the project study area include the extension of Dockweiler Drive as a part of the NNSP Stage II EIR. All of these roadways are consistent with the City s Circulation Element. Motor vehicle noise on roadways is the primary noise source in the project area. The following roadways provide the main access to the project area: Railroad Avenue (formerly San Fernando Road) is a north-south major highway from Magic Mountain Parkway to Lyons Avenue and a secondary highway from Lyons Avenue to Newhall Avenue. This roadway provides two lanes in each direction and limited parking through the project area. Newhall Avenue is a north-south secondary highway from 16 th Street to Railroad Avenue with one lane in each direction. From Railroad Avenue to State Route 14 (SR-14), Newhall Avenue is designated as a major highway with three northbound lanes and three southbound lanes south of Railroad Avenue. Lyons Avenue is an east-west major highway in the project area. Two to three lanes in each direction are provided with traffic signals and left turn channelization at major intersections. 13 th Street is an east-west unimproved local roadway. This roadway provides access to The Master's College and the Placenta Canyon neighborhood via its intersection with Railroad Avenue. One lane is provided in each direction. As part of the Master's College Master Development plan, the future main access to the college will be moved from 13 th Street/Placerita Canyon Road to the extended Dockweiler Drive along the south side of the campus. Dockweiler Drive is designated as an east-west secondary highway from Sierra Highway to Railroad Avenue. The existing portion of Dockweiler Drive currently extends from Sierra Highway to Leonard Tree Lane. The Metro railroad tracks, which run parallel to Railroad Avenue along the western border of the NNSP, are also a significant source of noise. The Metro railroad tracks handle two types of trains in the Santa Clarita area: Metrolink commuter rail and freight. Of the two, freight rail noise is the more dominant noise source. Based on 2009 train schedules, 24 Metrolink trains traverse Santa Clarita Valley each day. Approximately eight freight trains pass through the study area per day. The major freeways serving the region include Interstate 5 (I-5) and SR-14. Full access to the I-5 is provided from Lyons Avenue approximately 2 miles west of the project area. SR-14 is located approximately 2 miles southeast of the project site with full access provided from Newhall Avenue. The proposed project is not expected to directly alter traffic conditions on I-5 or SR-14. Therefore, noise impacts are not assessed for I-5 or SR-14. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

15 Methodology The analysis for future noise levels presented in this section is based on noise monitoring, published guidance, noise prediction modeling, empirical observations, and traffic volume data provided in the traffic analysis for the proposed project. The Caltrans Technical Noise Analysis Protocol recommends that projects evaluate both construction and operational noise in accordance with CEQA. 9 Existing ambient noise levels were monitored at selected locations in the project area corresponding to representative land uses that would potentially be impacted by the project. The measurements were taken using Larson Davis Model 820 sound level meters, which satisfy the American National Standards Institute (ANSI) for general environmental noise measurement instrumentation. The sound meters were equipped with an omni-directional microphone, calibrated before the day s measurements, and set at approximately 5 feet above ground. Noise levels for the operation of construction equipment were estimated using guidance provided by the United States Environmental Protection Agency (U.S. EPA). Potential construction noise sources were identified and noise levels were estimated along with reasonably anticipated distances between the construction noise sources and nearby noise sensitive land uses. Noise levels were estimated in accordance with the guidance documents previously identified and impacts were evaluated with respect to the established significance thresholds discussed later in this section. Roadway noise levels were modeled using the FHWA Highway Traffic Noise Prediction Model (FHWA-RD ). This model calculates the average noise level in db(a) CNEL along a given roadway segment based on traffic volumes, vehicle mix, average speeds, roadway geometry, and site conditions. The model calculates noise associated with a specific line source and the results characterize noise generated only by motor vehicle traffic along the specific roadway segment and do not reflect other noise sources in the project area. The model calculates noise associated with a specific line source and the results characterize noise generated only by motor vehicle traffic along the specific roadway segment and do not reflect other noise sources in the project area. The model incorporates a factor that characterizes the surface conditions of the area. This is called an alpha factor. An acoustically hard site uses an alpha factor of zero while an acoustically soft site uses an alpha factor of 0.5. The greater the alpha factor, the greater noise attenuates with increasing distance. The site is characterized as an acoustically hard site since the area is predominantly paved. Therefore, the model utilized an alpha factor value of 0. 9 California Department of Transportation, Division of Environmental Analysis, Traffic Noise Analysis Protocol, (2006). Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

16 Average vehicle noise rates (energy rates) utilized in the FHWA model have been modified to reflect average vehicle noise rates identified for California by Caltrans. 10 According to data collected by Caltrans, California automobile noise is 0.8 to 1.0 db(a) louder than national levels while medium and heavy truck noise is 0.3 to 3.0 db(a) quieter than national levels. 11 Traffic volumes utilized as data inputs to the noise prediction model were based on information provided by the traffic analysis for the proposed project. Noise levels were evaluated with respect to the established significance thresholds discussed later in this section. Ground-borne vibration impacts were evaluated using the FTA s Transit Noise and Vibration Impact Assessment guidance document. 12 Potential vibration sources in the project include the Metrolink and freight trains as well as construction equipment in operation during project construction. Vibration levels were estimated for these sources given reasonably anticipated distances between the vibration sources and nearby vibration sensitive land uses. Vibration levels were estimated in accordance with the FTA guidance and impacts were evaluated with respect to the established significance thresholds discussed later in this section. EXISTING CONDITIONS Predominance Noise Sources The project area is located in the DNSP and the proposed NNSP within the Santa Clarita Valley. Vehicular access to the project study area includes Railroad Avenue, Lyons Avenue, and Newhall Avenue. Vehicular access to Placerita Canyon, The Master's College, Deputy Jake and Vista Valencia Neighborhoods, and the North Newhall and Downtown Newhall area is currently limited to the 13 th Street roadway connection at Railroad Avenue and Sierra Highway. The 13 th Street roadway east of Railroad Avenue is unimproved and physically restricted by an active, antiquated at-grade railroad crossing. 13 th Street is classified as a local two-lane roadway and provides the only east-west access to the area currently developed with residential, institutional, and limited commercial uses. In addition, Placerita Canyon Road, a private two-lane roadway, connects to 13 th Street via Arch Street and extends easterly to Sierra Highway. Placerita Canyon Road has been closed to non-residents via controlled gates west of Sierra Highway. 10 Rudolf W. Hendriks, California Vehicle Noise Emission Levels, (Sacramento, California: California Department of Transportation, January 1987), NTIS, FHWA/CA/TL-87/ Rudolf W. Hendriks, California Vehicle Noise Emission Levels. 12 Federal Transit Administration, Office of Planning and Environment, Transit Noise and Vibration Impact Assessment, (2006). Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

17 As described above in Project Study Area, the major sources of noise would consist of vehicular noise along Railroad Avenue, Lyons Avenue, Newhall Avenue, and 13 th Street. The Metro railroad tracks, which run parallel to Railroad Avenue along the western border of the proposed project, are also a significant source of noise. Off-Site Measured Ambient Noise Levels Short-term noise monitoring was conducted on September 15, 2009, (weekday) at four locations in the study area in order to characterize the ambient 13 noise environment. Figure 5.5-6, Noise Monitoring Locations, depicts the four short-term noise monitoring locations. Weather conditions were fair with generally calm to low wind speeds, with gusts up to 13 miles per hour. The resulting short-term noise levels are provided in Table 5.5-2, Short-Term Monitored Noise Levels. Monitoring was conducted between the hours of approximately 8:40 AM to 10:05 AM with a sampling duration of approximately 15 minutes at each location. Table Short-Term Monitored Noise Levels Noise Level Map Ref. Location (db(a) Leq,15) 1 9 th Street and Chestnut Street th Street and Spruce Street th Street and Walnut Street Pine Street and Market Street 68.4 Source: Impact Sciences. Inc., (2009). The short-term noise measurements are provided in Appendix 5.5 of this EIR. The first short-term monitoring location was located near the intersection of 9 th Street and Chestnut Street, approximately 1,075 feet southwest of the Lyons Avenue and Railroad Avenue intersection. The noise monitor was placed adjacent to a residential land use on the southwest corner, approximately 27 feet from the centerline of Chestnut Street. The primary sources of noise at this location include traffic traveling northbound and southbound along Chestnut Street and eastbound and westbound along 9 th Street and Lyons Avenue, which lies one block to the north. 13 Ambient noise level is the level of existing noise occurring in the surrounding area, sometimes referred to as background noise. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

18 3 2 n Legend: X Project Site Noise Measurement Locations APPROXIMATE SCALE IN FEET 1 4 Pine ine ine St St SOURCE: Image: Google Earth - May 2006; Impact Sciences, Inc. January 2010 FIGURE Noise Monitoring Locations /10

19 The second short-term monitoring location was located near the intersection of 11 th Street and Spruce Street, just west of the Lyons Avenue and Railroad Avenue intersection. The noise monitor was placed adjacent to a residential land use on the southeast corner, approximately 26 feet from the centerline of 11 th Street and 49 feet from the centerline of Spruce Street. The primary sources of noise at this location include traffic traveling northbound and southbound along Spruce Street and eastbound and westbound along 11 th Street. In addition, traffic along Lyons Avenue and commuter and freight trains traveling along the Metro railroad tracks, which are located one block to the east, are primary sources of noise. During the monitoring period, noise due to a trainwithitshornblowingwassampled. The third short-term monitoring location was located near the intersection of 11 th Street and Walnut Street, just west of the Lyons Avenue and Railroad Avenue intersection. The noise monitor was placed adjacent to a residential land use on the northeast corner, approximately 23 feet from the centerline of Walnut Street and 179 feet from the centerline of 11 th Street. The Newhall Elementary School is located across Walnut Street. The primary sources of noise at this location include traffic traveling northbound and southbound along Walnut Street and eastbound and westbound along 11 th Street. Lyons Avenue is located about two blocks to the south while Railroad Avenue and the Metro railroad tracks are located about two blocks to the east. The fourth short-term monitoring location was located near the intersection of Pine Street and Market Street, approximately 1,400 feet southeast of the Lyons Avenue and Railroad Avenue intersection. The noise monitor was placed adjacent to residential land uses along the eastern side of Pine Street, approximately 30 feet from the centerline of Pine Street and 198 feet from Market Street. The Metro railroad tracks run parallel to Pine Street to the west, approximately 87 feet from the noise monitoring location. The primary sources of noise at this location include traffic traveling northbound and southbound along Pine Street and Railroad Avenue, which lies one block to the west, and eastbound and westbound along Market Street. In addition, commuter and freight trains traveling along the Metro railroad tracks are primary sources of noise. During the monitoring period, noise due to a train with its horn blowing was sampled in addition to noise from the railroad crossing guards being activated on Market Street. Roadway Noise Levels In order to characterize the ambient roadway noise environment in the study area, noise prediction modeling was conducted based on vehicular traffic volumes along nearby roadway segments. Noise levels were modeled using the FHWA Highway Traffic Noise Prediction Model (FHWA-RD ). This model calculates the average noise level in db(a) CNEL along a given roadway segment based on traffic Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

20 volumes, vehicle mix, average speeds, roadway geometry, and site conditions. The project site is characterized as an acoustically hard site since the area is predominantly paved. As shown in Table 5.5-3, Existing Roadway Noise Levels, the roadway segments near the proposed project range from a low of 63.6 db(a) CNEL to a high of 69.5 db(a) at a distance of 75 feet from the roadway centerline. Levels less than 70 db(a) CNEL are considered conditionally acceptable for singleand multi-family residences in accordance with the City of Santa Clarita City Land Use Compatibility Guidelines, which are discussed below in the Regulatory Setting section. Levels above 70 db(a) CNEL are considered normally unacceptable for single- and multi- family residences. Refer to the traffic analysis for the project for a detailed discussion of existing traffic levels. 14 Noise model calculations are available in Appendix 5.5. Table Existing Roadway Noise Levels CNEL in db(a) at 75 Feet from Roadway Segment Roadway Centerline Railroad Avenue North of 13 th Street th Street East of Railroad Avenue 63.6 Railroad Avenue North of Newhall Avenue 67.7 Newhall Avenue Northwest of Railroad Avenue 66.3 Lyons Avenue West of Railroad Avenue 64.1 Lyons Avenue West of Newhall Avenue 68.2 Newhall Avenue Southeast of Railroad Avenue 69.5 Sources: Impact Sciences, Inc. (2009). Calculations are provided in Appendix 5.5. REGULATORY SETTING Noise Criteria Federal Federal regulations address highway noise and are defined in the Code of Federal Regulations, Title 23, Part 772 (23 CFR 772), which provides procedures for the preparation of construction and operational noise studies and evaluating noise abatement considered for federal-aid highway projects. All highway 14 Overland Traffic Consultants, Traffic Analysis for the Relocation of the 13 th Street Railroad Crossing to Lyons Avenue in the City of Santa Clarita, (2010) 9. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

21 projects that are developed in conformance with 23 CFR 772 are deemed to be in conformance with the FHWA noise standards. Under 23 CFR 772.7, projects are categorized as Type I or Type II federal or federal-aid highway projects. A Type I project is defined as the construction of a highway on a new location, or the physical alteration of an existing highway which significantly changes either the horizontal or vertical alignment, or increases 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. The proposed project is not a Type I or a Type II federal or federal-aid highway project. State California Department of Health Services In 1972, the U.S. EPA determined that a yearly average day-night sound level of 45 db(a) would permit adequate speech communication in the home. The U.S. EPA also identified an indoor day/night level of 45 db(a) as necessary to protect against sleep interference. 15 Using this information and knowing that residential construction can attenuate noise by at least 25 db(a) with windows and doors closed (see Table 5.5-1), the State of California, Department of Health Services, Environmental Health Division (DHS), developed and published recommended guidelines for noise and land use compatibility, referred to as the State Land Use Compatibility Guidelines (see Figure 5.5-7, State Land Use Compatibility Guidelines for Noise). The DHS does not mandate application of this compatibility matrix to development projects; however, each jurisdiction is required to consider the State Land Use Compatibility Guidelines when developing its general plan noise element and when determining acceptable noise levels within its community. 16 The State Land Use Compatibility Guidelines identify an exterior (outdoor) noise level of 60 db(a) CNEL to be an acceptable level for single family, duplex, and mobile homes involving normal, conventional construction, without any special noise insulation requirements (normally acceptable noise levels). Exterior noise levels up to 65 db(a) CNEL/Ldn are typically considered acceptable for multi-family units and transient lodging without any special noise insulation requirements because interior noise levels will typically be reduced to acceptable levels (to at least 45 db(a) CNEL/Ldn) through conventional construction, but with closed windows and fresh air supply systems or air conditioning. Between these 15 Dr. Alice H. Suter, Administrative Conference of the United States: Noise and Its Effects, (November 1991), These guidelines are also published by the Governor s Office and Planning and Research in the State of California General Plan Guidelines (2003). Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

22 values and 70 db(a) CNEL/Ldn, exterior noise levels are typically considered acceptable only if the buildings are conditioned to include noise insulation features (conditionally acceptable noise levels) to achieve the 45 db(a) CNEL/Ldn interior noise level. An exterior noise level of 70 db(a) CNEL/Ldn is typically the dividing line between an acceptable and unacceptable exterior noise environment for all noise sensitive uses, including schools, libraries, places of worship, hospitals, day care centers, and nursing homes of conventional construction. Noise levels above 75 db(a) CNEL/Ldn may be considered normally unacceptable for office, commercial, and industrial uses. California Noise Insulation Standards The California Noise Insulation Standards of 1988 (California Code of Regulations Title 24, Section 3501 et seq.) require that interior noise levels from exterior sources be 45 db(a) or less in any habitable room of a multi-residential use facility (e.g., hotels, motels, dormitories, long-term care facilities, and apartment houses and other dwellings, except detached single-family dwellings) with doors and windows closed. Measurements are based on CNEL or Ldn, whichever is consistent with the noise element of the local general plan. Where exterior noise levels exceed 60 db(a) CNEL/Ldn, an acoustical analysis for new development is required to show that the proposed construction will reduce interior noise levels to 45 db(a) CNEL/Ldn. If the interior 45 db(a) CNEL/Ldn limit can be achieved only with the windows closed, the residence design must include mechanical ventilation that meets applicable Uniform Building Code (UBC) requirements. In unacceptable interior noise environments, additional noise insulation features, such as extra batting or resilient channels 17 in exterior walls, double paned windows, air conditioners to enable occupants to keep their windows closed, solid wood doors, noise baffles on exterior vents, etc., are typically needed to provide acceptable interior noise levels. The best type of noise insulation for a land use should be based on detailed acoustical analyses that identify all practical noise insulation features and that confirms their effectiveness. 17 A resilient channel is a pre-formed section of sheet metal approximately 0.5 inch deep by 2.5 inches wide by 12 inches long that is installed between wallboard panels and framing to reduce sound transmission through walls. By preventing the wallboard from lying against the studs, the channel inhibits the transmission of sound through the framing. Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

23 LAND USE CATEGORY COMMUNITY NOISE EXPOSURE Ldn or CNEL, db Residential - Low Density Single Family, Duplex, Mobile Homes Residential - Multi Family Transient Lodging - Motels, Hotels Schools, Libraries Churches, Hospitals, Nursing Homes Auditoriums, Concert Halls, Amphitheatres Sports Arena, Outdoor Spectator Sports Playgrounds, Neighborhood Parks Golf Courses, Riding Stables, Water Recreation, Cemeteries Office Buildings, Business Commercial and Professional Industrial, Manufacturing Utilities, Agriculture NORMALLY ACCEPTABLE Specified land use is satisfactory, based upon the assumption that any buildings involved are of normal conventional construction, without any special noise insulation requirements. CONDITIONALLY ACCEPTABLE New construction or development should be undertaken only after a detailed analysis of the noise reduction requirements is made and needed noise insulation features included in the design. Conventional construction, but with closed windows and fresh air supply systems or air conditioning will normally suffice. NORMALLY UNACCEPTABLE New construction or development should generally be discouraged. If new construction or development does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise reduction features included in the design. CLEARLY UNACCEPTABLE New construction or development should generally not be undertaken. SOURCE: California Governor s Office of Planning and Research, State of California General Plan Guidelines, Appendix C: Guidelines for the Preparation and Content of Noise Elements of the General Plan, October FIGURE State Land Use Compatibility Guidelines for Noise /10

24 Local City of Santa Clarita Noise Element The City has incorporated a slightly modified version of the State Land Use Compatibility Guidelines into its Noise Element, as well as noise level control standards that directly affect the proposed project. 18 These are used in this impact analysis as standards (measured in db(a) CNEL) to measure noise impacts; therefore, application of these guidelines to both on- and off-site project-related noise would meet the City s impact analysis requirements. The guidelines in the City s Noise Element are referred to as the City Land Use Compatibility Guidelines (see Figure 5.5-8, City Land Use Compatibility Guidelines for Noise). The Noise Element is herein incorporated by reference and is available for review at the City of Santa Clarita Planning and Community Development Department. Draft One Valley One Vision Noise Element One Valley One Vision (OVOV) is a joint effort between the County of Los Angeles, the City of Santa Clarita and Valley residents and businesses to create a single vision and guidelines for the future growth of the Valley and the preservation of natural resources. The result of this project will be a General Plan document for the buildout of the entire Santa Clarita Valley. The draft Noise Element was released in February The Noise Element is a comprehensive program for including noise management in the planning process, providing a tool for local planners to use in achieving and maintaining land uses that are compatible with existing and future environmental noise levels in the Santa Clarita Valley. The Draft OVOV Noise Element incorporates a slightly modified version of the State Land Use Compatibility Guidelines, which is identical to the City Land Use Compatibility Guidelines in the existing City of Santa Clarita General Plan Noise Element. City of Santa Clarita Noise Ordinance The City has also adopted an ordinance to control point source noise. This ordinance is also incorporated herein by reference and is available for review at the City s Web site. 19 Three sections of the ordinance are particularly pertinent to the proposed project: Sections , , and , as amended. 18 City of Santa Clarita, General Plan, Noise Element Amendment, (2000) N-6 and N-7. The General Plan Noise Element may be found at the City of Santa Clarita Planning Department. The Noise Ordinance is found at 19 The City of Santa Clarita Noise Ordinance may be viewed at the following Web site: Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

25 Section Section sets the following noise levels for residential, commercial, and manufacturing uses taking place on private property and for construction activities on private property outside of the hourly limits provided in Section The levels are shown in Table 5.5-4, City Ordinance Noise Limits. Table City Ordinance Noise Limits Region Time Exterior Sound Level (db) Residential Zone Day 65 Residential Zone Night 55 Commercial and Manufacturing Day 80 Commercial and Manufacturing Night 70 Source: City of Santa Clarita. Note: Wherever a boundary line occurs between a residential property and a commercial/manufacturing property, the noise level of the quieter zone is to be used. Section Section states, any noise level from the use or operation of any machinery, equipment, pump, fan, air conditioning apparatus, refrigerating equipment, motor vehicle, or other mechanical or electrical device, or in repairing or rebuilding any motor vehicle, which exceeds the noise limits as set forth in Section at any property line, or, if a condominium or rental units, within any condominium or rental unit within the complex, shall be a violation of this chapter. Construction work performed in conformance with Section (below) is exempt from Section Section , as Amended Section , as amended by Ordinance No and No. 00-3, prohibits construction work requiring a building permit on sites within 300 feet of a residentially zoned property from operating except between the hours of 7:00 AM and 7:00 PM Monday through Friday, and between 8:00 AM and 6:00 PM on Saturday. Construction work is prohibited on Sundays, New Year s Day, Independence Day, Thanksgiving Day, Christmas Day, Memorial Day, and Labor Day. The Community Development 20 Telephone conversation with Jeff Hogan, City of Santa Clarita Department of Community Development, Santa Clarita, California, December Impact Sciences, Inc Lyons Avenue At-Grade Rail Crossing: Stage I Draft EIR

26 SOURCE: City of Santa Clarita General Plan Update Noise Element FIGURE City Land Use Compatibility Guidelines for Noise /10