Many methods have been developed for evaluating community noise to account for, among other things:

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1 5.5 NOISE The purpose of this section is to analyze project-related noise source impacts on-site and to surrounding land uses. Mitigation measures are also recommended to avoid or lessen the project s impacts. This section evaluates short-term construction-related impacts as well as long-term buildout operational conditions. Information in this section is based on the Lancaster General Plan, Lancaster Municipal Code, and traffic information contained in the Downtown Lancaster Specific Plan Traffic Impact Analysis, prepared by RBF Consulting, dated April 2, 2008; refer to Appendix E, Data, for the assumptions utilized in this analysis ENVIRONMENTAL SETTING NOISE SCALES AND DEFINITIONS Sound is described in terms of the loudness (amplitude) of the sound and frequency (pitch) of the sound. The standard unit of measurement of the loudness of sound is the decibel (db). Since the human ear is not equally sensitive to sound at all frequencies, a special frequencydependent rating scale has been devised to relate noise to human sensitivity. The A-weighted decibel scale (dba) performs this compensation by differentiating among frequencies in a manner approximating the sensitivity of the human ear. Decibels are based on the logarithmic scale. The logarithmic scale compresses the wide range in sound pressure levels to a more usable range of numbers in a manner similar to the Richter scale is used to measure earthquakes. In terms of human response to noise, a sound 10 dba higher than another is perceived to be twice as loud and 20 dba higher is perceived to be four times as loud, and so forth. Everyday sounds normally range from 30 dba (very quiet) to 100 dba (very loud). Examples of various sound levels in different environments are illustrated on Exhibit 5.5-1, Common Environmental Levels. Many methods have been developed for evaluating community noise to account for, among other things: The variation of noise levels over time; The influence of periodic individual loud events; and The community response to changes in the community noise environment. Table 5.5-1, Descriptors, provides a listing of methods to measure sound over a period of time. HEALTH EFFECTS OF NOISE Human response to sound is highly individualized. Annoyance is the most common issue regarding community noise. The percentage of people claiming to be annoyed by noise generally increases with the environmental sound level. However, many factors also influence people s response to noise. The factors can include the character of the noise, the variability of the sound level, the presence of tones or impulses, and the time of day of the occurrence. Additionally, non-acoustical factors, such as the person s opinion of the noise source, the ability to adapt to the noise, the attitude towards the source and those associated with it, and the Final August

2 Source: Melville C. Branch and R. Dale Beland, Outdoor in the Metropolitan Environment, Environmental Protection Agency, Information on Levels of Environmental Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety (EPA/ONAC 550/ ), March /08 JN ENVIRONMENTAL IMPACT REPORT DOWNTOWN LANCASTER SPECIFIC PLAN Common Environmental Levels Exhibit 5.5-1

3 Term Table Descriptors Definition Decibel (db) The unit for measuring the volume of sound equal to 10 times the logarithm (base 10) of the ratio of the pressure of a measured sound to a reference pressure (20 micropascals). A-Weighted Decibel (dba) A sound measurement scale that adjusts the pressure of individual frequencies according to human sensitivities. The scale accounts for the fact that the region of highest sensitivity for the human ear is between 2,000 and 4,000 cycles per second (hertz). Equivalent Sound Level (Leq) The sound level containing the same total energy as a time varying signal over a given time period. The Leq is the value that expresses the time averaged total energy of a fluctuating sound level. Maximum Sound Level (Lmax) The highest individual sound level (dba) occurring over a given time period. Minimum Sound Level (Lmin) The lowest individual sound level (dba) occurring over a given time period. Community Equivalent Level (CNEL) A rating of community noise exposure to all sources of sound that differentiates between daytime, evening, and nighttime noise exposure. These adjustments are +5 dba for the evening, 7:00 PM to 10:00 PM, and +10 dba for the night, 10:00 PM to 7:00 AM. Day/Night Average (Ldn) The Ldn is a measure of the 24-hour average noise level at a given location. It was adopted by the U.S. Environmental Protection Agency for developing criteria for the evaluation of community noise exposure. It is based on a measure of the average noise level over a given time period called the Leq. The Ldn is calculated by averaging the Leq s for each hour of the day at a given location after penalizing the sleeping hours (defined as 10:00 PM to 7:00 AM) by 10 dba to account for the increased sensitivity of people to noises that occur at night. Exceedance Level (Ln) The A-weighted noise levels that are exceeded 1%, 10%, 50%, and 90% (L01, L10, L50, L90, respectively) of the time during the measurement period. Source: Cyril M. Harris, Handbook of Control, predictability of the noise, all influence people s response. As such, response to noise varies widely from one person to another and with any particular noise, individual responses will range from not annoyed to highly annoyed. When the noise level of an activity rises above 70 dba, the chance of receiving a complaint is possible, and as the noise level rises, dissatisfaction among the public steadily increases. The effects of noise are often only transitory, but adverse effects can be cumulative with prolonged or repeated exposure. The effects of noise on the community can be organized into six broad categories: -Induced Hearing Loss; Interference with Communication; Effects of on Sleep; Effects on Performance and Behavior; Extra-Auditory Health Effects; and Annoyance. Final August

4 Although it often causes discomfort and sometimes pain, noise-induced hearing loss usually takes years to develop. -induced hearing loss can impair the quality of life through a reduction in the ability to hear important sounds and to communicate with family and friends. Hearing loss is one of the most obvious and easily quantified effects of excessive exposure to noise. While the loss may be temporary at first, it could become permanent after continued exposure. When combined with hearing loss associated with aging, the amount of hearing loss directly caused by the environment is difficult to quantify. Although the major cause of noiseinduced hearing loss is occupational, substantial damage can be caused by non-occupational sources. According to the United States Public Health Service, nearly ten million of the estimated 21 million Americans with hearing impairments owe their losses to noise exposure. can mask important sounds and disrupt communication between individuals in a variety of settings. This process can cause anything from a slight irritation to a serious safety hazard, depending on the circumstance. can disrupt face-to-face communication and telephone communication, and the enjoyment of music and television in the home. It can also disrupt effective communication between teachers and pupils in schools, and can cause fatigue and vocal strain in those who need to communicate in spite of the noise. Interference with communication has proved to be one of the most important components of noise-related annoyance. -induced sleep interference is one of the critical components of community annoyance. Sound level, frequency distribution, duration, repetition, and variability can make it difficult to fall asleep and may cause momentary shifts in the natural sleep pattern, or level of sleep. It can produce short-term adverse effects on mood changes and job performance, with the possibility of more serious effects on health if it continues over long periods. can cause adverse effects on task performance and behavior at work, and nonoccupational and social settings. These effects are the subject of some controversy, since the presence and degree of effects depends on a variety of intervening variables. Most research in this area has focused mainly on occupational settings, where noise levels must be sufficiently high and the task sufficiently complex for effects on performance to occur. Recent research indicates that more moderate noise levels can produce disruptive after-effects, commonly manifested as a reduced tolerance for frustration, increased anxiety, decreased incidence of helping behavior, and increased incidence of hostile behavior. has been implicated in the development or exacerbation of a variety of health problems, ranging from hypertension to psychosis. As with other categories, quantifying these effects is difficult due to the amount of variables that need to be considered in each situation. As a biological stressor, noise can influence the entire physiological system. Most effects seem to be transitory, but with continued exposure some effects have been shown to be chronic in laboratory animals. Annoyance can be viewed as the expression of negative feelings resulting from interference with activities, as well as the disruption of one s peace of mind and the enjoyment of one s environment. Field evaluations of community annoyance are useful for predicting the consequences of planned actions involving highways, airports, road traffic, railroads, or other noise sources. The consequences of noise-induced annoyance are privately held dissatisfaction, publicly expressed complaints to authorities, and potential adverse health effects, as discussed above. In a study conducted by the United States Department of Transportation, the effects of annoyance to the community were quantified. In areas where noise levels were consistently above 60 dba CNEL, approximately nine percent of the community is highly annoyed. When levels exceed 65 dba CNEL, that percentage rises to 15 percent. Although evidence for the various effects of noise have differing levels of certainty, it is Final August

5 clear that noise can affect human health. Most of the effects are, to a varying degree, stress related. Ground-Borne Vibration Vibration is an oscillatory motion through a solid medium in which the motion s amplitude can be described in terms of displacement, velocity or acceleration. The peak particle velocity or the root mean square velocity is usually used to describe vibration amplitudes. The peak particle velocity is defined as the maximum instantaneous peak or vibration signal, while the root mean square is defined as the square root of the average of the squared amplitude of the signal. The peak particle velocity is typically used for evaluating potential building damage, whereas the root mean square is typically more suitable for evaluating human response. Typically, ground-borne vibration generated by man-made activities attenuates rapidly with distance from the source of vibration. Man-made vibration issues are therefore usually confined to short distances (i.e., 500 feet or less) from the source. Both construction and operation of development projects can generate ground-borne vibration. In general, demolition of structures preceding construction generates the highest vibrations. Construction equipment, such as vibratory compactors or rollers, pile drivers and pavement breakers, can generate perceptible vibration during construction activities. Heavy trucks can also generate ground-borne vibrations that vary depending on vehicle type, weight and pavement conditions. Exhibit 5.5-2, Typical Vibration Sources and Sensitivities, lists typical vibration sources and their effects LAWS, ORDINANCES, REGULATIONS, AND STANDARDS Land uses deemed sensitive by the State of California (State) include schools, hospitals, rest homes, and long-term care and mental care facilities. Many jurisdictions also consider residential uses particularly noise-sensitive because families and individuals expect to use time in the home for rest and relaxation, and noise can interfere with those activities. Some jurisdictions may also identify other noise-sensitive uses such as churches, libraries, and parks. Land uses that are relatively insensitive to noise include office, commercial, and retail developments. There is a range of insensitive noise receptors that include uses that generate significant noise levels and that typically have a low level of human occupancy. This noise analysis was conducted in accordance with Federal, State, and local criteria described in the following sections. U.S. ENVIRONMENTAL PROTECTION AGENCY The Environmental Protection Agency offers guidelines for community noise exposure in the publication Effects Handbook A Desk Reference to Health and Welfare Effects of. These guidelines consider occupational noise exposure as well as noise exposure in homes. The Environmental Protection Agency recognizes an exterior noise level of 55 decibels daynight level (db Ldn) as a general goal to protect the public from hearing loss, activity interference, sleep disturbance, and annoyance. The Environmental Protection Agency and other Federal agencies have adopted suggested land use compatibility guidelines that indicate that residential noise exposures of 55 to 65 db Ldn are acceptable. The Environmental Protection Agency notes, however, that these levels are not regulatory goals, but are levels defined by a negotiated scientific consensus, without concern for economic and technological feasibility or the needs and desires of any particular community. Final August

6 Source: Nugent & Amick, 1992, Environmental Monitor Vibration Consideratons in Land Use Planning, Summer Ogden, 1995, Typical Vibration Sources and Sensitivities. 08/08 JN ENVIRONMENTAL IMPACT REPORT DOWNTOWN LANCASTER SPECIFIC PLAN Typical Vibration Sources and Sensitivities Exhibit 5.5-2

7 STATE OF CALIFORNIA California Environmental Quality Act The California Environmental Quality Act (CEQA) was enacted in 1970 and requires that all known environmental effects of a project be analyzed, including environmental noise impacts. Under CEQA, a project has a potentially significant impact if the project exposes people to noise levels in excess of standards established in the local general plan or noise ordinance. Additionally, under CEQA, a project has a potentially significant impact if the project substantially increases the ambient noise levels in the project vicinity above levels existing without the project. If a project has a potentially significant impact, mitigation measures must be considered. If mitigation measures to reduce the impact to less than significant are not feasible because of economic, social, environmental, legal, or other conditions, the most feasible mitigation measures must be considered. California Government Code California Government Code Section 65302(f) mandates that the legislative body of each county and city adopt a noise element as part of its comprehensive general plan. The local noise element must recognize the land use compatibility guidelines established by the State Department of Health Services, as shown in Table 5.5-2, California Land Use Compatibility Guidelines. The guidelines rank noise-land use compatibility as normally acceptable, conditionally acceptable and clearly unacceptable noise levels for various land use types. Single-family homes are normally acceptable in exterior noise environments up to 60 CNEL and conditionally acceptable up to 70 CNEL. Multiple-family residential uses are normally acceptable up to 65 CNEL and conditionally acceptable up to 70 CNEL. Schools, libraries, and churches are normally acceptable up to 70 CNEL, as are office buildings and business, commercial and professional uses. LOCAL JURISDICTION General Plan Local agencies, such as the City of Lancaster, may regulate most noise level sources not regulated by the Federal government by providing standards for insulation of noise receivers, either within the structure or by placement of noise barriers, such as walls. Furthermore, a local agency may adopt land use decisions or project-related conditions that may reduce noise impacts by separating noise generators from noise sensitive uses. The City is currently updating their General Plan. However, this analysis utilizes the current General Plan. The City has adopted the land use compatibility data outlined in Table as a planning guideline. 1 Table 5.5-3, City of Lancaster Normalized CNEL Corrections, identifies correction factors that the City utilizes to modify the compatibility assessments described in Table City of Lancaster, Public Health and Safety Element, Page III-C Ibid. Final August

8 Table California Land Use Compatibility Guidelines Land Use Category Normally Acceptable Community Exposure (CNEL) Conditionally Acceptable Normally Unacceptable Clearly Unacceptable Residential - Low Density, Single-Family, Duplex, Mobile Homes Residential - Multiple Family Transient Lodging - Motel, Hotels Schools, Libraries, Churches, Hospitals, Nursing Homes Auditoriums, Concert Halls, Amphitheaters NA NA Sports Arenas, Outdoor Spectator Sports NA NA Playgrounds, Neighborhood Parks NA Golf Courses, Riding Stables, Water Recreation, Cemeteries NA Office Buildings, Business Commercial and Professional NA Industrial, Manufacturing, Utilities, Agriculture NA Source: Office of Planning and Research, California, General Plan Guidelines, October CNEL = community noise equivalent level; NA = not applicable. 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 have been 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 be discouraged. If new construction or development does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise-insulation features must be included in the design. CLEARLY UNACCEPTABLE: New construction or development should generally not be undertaken. Final August

9 Table City of Lancaster Normalized CNEL Corrections Type of Correction Description Measured CNEL Change (dba) 1 Seasonal Summer (or year-round operation) 0 Correction Winter only (or windows always closed) -5 Quiet suburban or rural community (remote from large cities and from industrial activity and trucking). +10 Quiet suburban or rural community (not located near industrial activity). +5 Correction for Urban residential community (not immediately adjacent to heavily traveled roads Outdoor Residual 0 and industrial areas). Level Noisy urban residential community (near relatively busy roads or industrial -5 areas). Very noisy urban residential community. -10 No prior experience with the intruding noise. +5 Community has had some previous exposure to noise, but little effort is being made to control the noise. This correction may also be applied in a situation 0 Correction for Previous Exposure where the community has not been exposed to the noise previously, but the people are aware that bona fide efforts are being made to control the noise. and Community Community has had considerable previous exposure to the intruding noise and Attitudes the noisemaker s relations with the community are good. -5 Community is aware that the operation causing noise is very necessary and will not continue indefinitely. This correction can be applied for an operation of -10 limited duration and under emergency circumstances. Pure Tone or No pure tone or impulsive in character. 0 Impulse Pure tone or impulsive character present. -5 Source: California Office of Control, Guidelines for the Preparation and Content of Elements of the General Plan, February CNEL = community noise equivalent level; dba = A-weighted decibel. 1 Corrections to be added to the measured CNEL to obtain normalized CNEL. Section III, Plan for Public Health and Safety, of the City of Lancaster General Plan, includes an objective (Objective 4.3) to promote noise compatible land use relationships with the implementation of noise standards identified in Table 5.5-4, -Compatible Land Use Objectives. The standards are to be utilized for design purposes in new development and to establish a program to attenuate existing noise problems. 3 The following policies are identified for Objective 4.3 in Section 5.7 of the General Plan : Policy 4.3.1: Policy 4.3.2: Policy Ensure that noise-sensitive land uses and noise generators are located and designed in such a manner that City noise objective will be achieved. (Refer to the Stationary Sources discussion below.) Ensure that the provision of noise attenuation does not create significant negative visual impacts. 3 City of Lancaster, General Plan, Objective 4.3, October 28, 1997, Page III-15. Final August

10 Table Compatible Land Use Objectives Land Use Maximum Exterior CNEL Maximum Interior CNEL Rural, Single-, and Multiple-Family Residential Dwellings 65 dba 45 dba Schools: Classrooms Playgrounds 65 dba 70 dba 45 dba --- Libraries dba Hospitals and Convalescent Facilities: Living Areas Sleeping Areas Commercial and Industrial Office Areas dba --- Source: City of Lancaster General Plan, Table III-1, Compatible Land Use Objectives. CNEL = community noise equivalent level. 50 dba 40 dba dba Mobile Sources Vehicular traffic noise is subject to the noise standards identified in Table 5.5-4, as set forth by the City of Lancaster. Stationary Sources As stated above, the City of Lancaster General Plan established maximum exterior and interior noise levels for land uses in the City; refer to Table The following policy relevant to stationary noise sources is outlined in the General Plan: Policy 4.3.2: Wherever feasible, manage the generation of single event noise equivalent levels (SENEL) from motor vehicles, trains, aircraft, commercial, industrial, construction, and other activities such that SENEL are no greater than 15 dba above the noise objectives included in the Plan for Public Health and Safety. The City has further adopted provisions in the Lancaster Municipal Code to regulate excessive and offensive noise. According to Chapter 8.24 of the Health and Safety Code ( Regulation), it is the policy of the City to prohibit unnecessary, excessive and annoying noises from all sources subject to its police power. With respect to construction and building, Section (Loud, Unnecessary and Unusual s Prohibited-Construction and Building) states the following: Except as otherwise provided in this chapter, a person at any time on Sunday or any day between the hours of eight PM and sunrise shall not perform any construction or repair work of any kind upon any building or structure or perform any earth excavating, filling or moving where any of the foregoing entails the use of any air compressor, jack hammer, power-driven drill, riveting machine, excavator, diesel-powered truck, tractor or other earth-moving equipment, hard hammers on steel or iron or any other machine tool, Final August

11 device or equipment which makes loud noises within five hundred (500) feet of an occupied dwelling, apartment, hotel, mobilehome or other place of residence. Section (Exceptions) states the following: The provisions of Section do not apply to any person who performs the construction, repair, excavation or moving work pursuant to the express written permission of the City Engineer to perform such work at times prohibited in Section Upon receipt of an application stating the reasons for the request, the City Engineer may grant such permission if he finds that: 1. The work proposed to be done is effected with the public interest; or 2. Hardship or injustice or unreasonable delay would result with the interruption thereof within the hours and days specified in Section ; or 3. The building or structure involved is devoted or intended to be devoted to a use immediately incident to public interest; or 4. The provisions of Section do not apply to the construction, repair or excavation during prohibited hours as may be necessary to restore property to a safe condition following a public calamity or work required to protect persons or property from imminent exposure to danger or work by private or public utility companies when restoring utility service EXISTING NOISE ENVIRONMENT SENSITIVE RECEPTORS Certain land uses are considered particularly sensitive to noise: schools, hospitals, rest homes, long-term medical and mental care facilities and parks and recreation areas. Residential areas are also considered noise-sensitive, especially during the nighttime hours. The Downtown Lancaster Specific Plan (DLSP) area consists of 140 acres that includes a number of sensitive receptors. Additionally, the project area is directly adjacent to residential neighborhoods, schools and healthcare facilities. STATIONARY NOISE SOURCES The primary sources of stationary noise in the project vicinity are urban-related activities (i.e., mechanical equipment, loading and unloading areas, parking lots, landscape maintenance, conversations [normal to loud], and recreational areas) and residential activities (i.e., air conditioners, pool and spa equipment, landscape maintenance, and conversations). associated with these sources may represent a single event noise occurrence, short-term, or long-term/continuous noise. MOBILE NOISE SOURCES Vehicular noise along major roadways was modeled to estimate existing noise levels from mobile traffic. The existing and future roadway noise levels in the vicinity of the proposed Final August

12 project were projected using the Federal Highway Administration (FHWA) Traffic Prediction Model (RD ), together with several roadway and site parameters. The FHWA model is based upon reference energy mean emission levels (REMELS) for automobiles, medium trucks (2 axles) and heavy trucks (3 or more axles), with consideration given to vehicle volume, speed, roadway configuration, distance to the receiver, and the acoustical characteristics of the site. To predict CNEL values, it is necessary to determine the hourly distribution of traffic for a typical day and adjust the traffic volume input data to yield an equivalent hourly traffic volume. The Calveno traffic noise emission curves are used as recommended by the California Department of Transportation (Caltrans) to more accurately calculate noise levels generated by California traffic. Traffic volumes used in the FHWA model were obtained from the Downtown Lancaster Specific Plan Traffic Impact Analysis prepared by RBF Consulting. Other traffic model inputs were obtained from field observations or from the General Plan. These traffic inputs determine the projected impact of vehicular traffic noise and include the roadway cross section (e.g., number of lanes), roadway width, average daily traffic (), vehicle travel speed, percentages of automobile and truck traffic, roadway grade, angle of view, and site conditions (hard or soft). The model does not account for ambient noise levels (i.e., noise from adjacent land uses) or topographical differences between the roadway and adjacent land uses. Table 5.5-5, Existing Traffic Levels, indicates the location of the 60-, 65-, and 70-CNEL noise contours associated with vehicular traffic along local roadways as modeled with the FHWA computer model. Roadway Segment Table Existing Traffic Levels 100 feet from Roadway Centerline Distance from Roadway Centerline to: (Feet) 60 CNEL 65 CNEL 70 CNEL 10th Street West Avenue J to Avenue J-8 26, Avenue I to Jackman Street 17, Kildare Street to Lancaster Boulevard 16, Newgrove Street to Avenue J 23, South of Lancaster Boulevard 19, th Street West Lancaster Boulevard to Avenue J 10, th Street West Avenue J to Avenue J-8 32, Lancaster Boulevard to Avenue J 13, Avenue I 10th Street West to Sierra Highway 26, th Street to 10th Street 23, th Street to 15th Street 26, Sierra Avenue to Division Street 23, SR-14 to 20th Street 24, West of SR-14 25, Final August

13 Roadway Segment Table [continued] Existing Traffic Levels 100 feet from Roadway Centerline Distance from Roadway Centerline to: (Feet) 60 CNEL 65 CNEL 70 CNEL Avenue J 10th Street to Sierra Avenue 35, th Street to 10th Street 30, Sierra Avenue to Division Street 34, SR-14 to 20th Street 32, Avenue J-8 20th Street to 15th Street 14, West of SR-14 15, Beech Avenue Kettering Street to Lancaster Boulevard 1, Lancaster Boulevard to Milling Street 1, Milling Street to Newgrove Street 1, North of Kettering Street Cedar Avenue Kettering Street to Lancaster Boulevard 1, Lancaster Boulevard to Milling Street Milling Street to Newgrove Street North of Kettering Street 1, Date Avenue Kettering Street to Lancaster Boulevard 1, Lancaster Boulevard to Milling Street 1, Milling Street to Newgrove Street North of Kettering Street Division Street South of Lancaster Boulevard 8, Elm Avenue Kettering Street to Lancaster Boulevard 1, Lancaster Boulevard to Milling Street North of Kettering Street 1, Fern Avenue Avenue I to Jackman Street 2, Kettering Street to Kildare Street 2, Kildare Street to Lancaster Boulevard 3, Lancaster Boulevard to Milling Street 1, North of Kettering 2, Newgrove Street to Avenue J 1, Fig Avenue Lancaster Boulevard to Milling Street North of Kettering Street Gadsden Avenue Kildare Street to Lancaster Boulevard 1, Lancaster Boulevard to Milling Street Genoa Avenue Lancaster Boulevard to Milling Street 1, Final August

14 Roadway Segment Table [continued] Existing Traffic Levels 100 feet from Roadway Centerline Distance from Roadway Centerline to: (Feet) 60 CNEL 65 CNEL 70 CNEL Kettering Street Cedar Avenue to Beech Avenue Date Avenue to Cedar Avenue Elm Avenue to Date Avenue Fern Avenue to Fig Avenue Fig Avenue to Elm Avenue Kildare Street 10th Street West to Gadsden Avenue 1, Gadsden Avenue to Fern Avenue 1, Lancaster Boulevard 10th Street West to Genoa Avenue 19, th Street West to 10th Street West 14, th Street West to 10th Street West 17, th Street West to 15th Street West 20, Beech Avenue to Sierra Highway 14, Cedar Avenue to Beech Avenue 15, Date Avenue to Cedar Avenue 14, East of Sierra Highway 11, Elm Avenue to Date Avenue 15, Fern Avenue to Fig Avenue 16, Fig Avenue to Elm Avenue 16, Gadsden Avenue to Fern Avenue 17, Genoa Avenue to Gadsden Avenue 20, Milling Street Beech Avenue to Sierra Highway 1, Cedar Avenue to Beech Avenue 1, Date Avenue to Cedar Avenue 1, Elm Avenue to Date Avenue 1, Fern Avenue to Fig Avenue 1, Fig Avenue to Elm Avenue 1, Gadsden Avenue to Fern Avenue Genoa Avenue to Gadsden Avenue Newgrove Street Cedar Avenue to Beech Avenue 1, Date Avenue to Cedar Avenue 1, Sierra Highway Lancaster Boulevard to Milling Street 15, Milling Street to Newgrove Street 16, North of Avenue I 7, North of Lancaster Boulevard 12, South of Avenue J 20, South of Newgrove Street 18, Source: Traffic modeling is based upon data contained within the Downtown Lancaster Specific Plan Traffic Impact Analysis, prepared by RBF Consulting, August 13, = average daily trips; dba = A-weighted decibels; CNEL = community noise equivalent level. Final August

15 RAILROAD NOISE The Mojave Mainline of the Union Pacific Transportation Company runs parallel to Sierra Highway and traverses the eastern portion of the project area. An estimated 12 trips (one-way) are made daily along this line. Diesel freight trains utilize this line, running at any time of the day or night, as necessitated by market demand. These freight trains travel at average speeds of approximately 45 miles per hour. The Metrolink Railway also utilizes the rail line. The Metrolink s last stop is at the station located near the Lancaster Boulevard/ Milling Street intersection. Table 8-12 of the Draft City of Lancaster Master Environmental Assessment (MEA) (Railroad s) illustrates the noise contours generated by the rail traffic along the Mojave Mainline and indicates a noise level of 66 Ldn at 200 feet from the railway centerline. It should be noted that this document is part of the General Plan Update process, and was issued for public review in April AMBIENT NOISE MEASUREMENTS To quantify existing ambient noise levels in the project area, RBF Consulting conducted noise surveys on July 25, The noise measurement sites were representative of existing noise exposure in a given time period (10 minutes) within the project area; refer to Exhibit 5.5-3, Measurement Locations. monitoring equipment used for the ambient noise survey consisted of a Brüel & Kjær Hand-held Analyzer Type 2250 equipped with a 4189 pre-polarized freefield microphone. The monitoring equipment complies with applicable requirements of the American National Standards Institute for Type I (precision) sound level meters. The results of the field measurements are indicated in Appendix E, Data. The results of the noise survey are outlined in Table 5.5-6, Ambient Measurements, which indicates that the highest noise level measurement (69.6 dba) was taken along Lancaster Boulevard and 10th Street West. Site No. Location Table Ambient Measurements Leq (dba) Time and Conditions 1 Kildare Street :35 AM clear and slight winds 2 Lancaster Boulevard and 10th Street West :00 AM clear and slight winds 3 Milling Street and Gadsden Avenue :15 AM clear and slight winds 4 Elm Avenue near Milling Street :28 AM clear and slight winds Cedar Avenue :45 AM clear and slight winds 6 Kettering Street and Beech Avenue :05 AM clear and slight winds 7 Milling Street and Sierra Highway :10 AM clear and slight winds Source: Monitoring Survey conducted by RBF Consulting (July 25, 2007). Leq = equivalent sound level; dba = A-weighted decibel. Final August

16 Source: City of Lancaster; NOT TO SCALE 08/08 JN ENVIRONMENTAL IMPACT REPORT DOWNTOWN LANCASTER SPECIFIC PLAN Measurement Locations Exhibit 5.5-3

17 5.5.4 IMPACT THRESHOLDS AND SIGNIFICANCE CRITERIA According to Appendix G of the CEQA Guidelines, a project would create a significant environmental impact if it would: Expose persons to, or generate, noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies; Expose persons to or generate excessive ground borne vibration or ground borne noise levels; Result in a substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project; Result in a substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project; For a project located within an airport land use plan or, where such a plan has not been adopted, within two miles of a public airport or public use airport, expose people residing or working in the project area to excessive noise levels; and For a project within the vicinity of a private airstrip, expose people residing or working in the project area to excessive noise levels. During preparation of the Initial Study, impacts associated with the fifth and sixth bullets were found to be less than significant. Please refer to Section 8.0, Effects Found Not to be Significant, for a detailed explanation. SIGNIFICANCE OF CHANGES IN AMBIENT NOISE LEVELS A project is considered to have a significant noise impact when it causes an adopted noise standard to be exceeded for the project site or for adjacent sensitive receptors. In addition to concerns regarding the absolute increase in noise level that might occur when a new source is introduced into an area, it is also important to consider the existing ambient noise environment. If the ambient noise environment is quiet and the new noise source greatly increases the noise exposure, an impact may occur even though a criterion level might not be exceeded. Lacking adopted standards for evaluating such impacts, a general standard for community noise environments is that an increase of over 5 dba, regardless of the ambient noise level without the project, is readily noticeable and is therefore considered a significant impact; refer to Table 5.5-7, Significance of Changes in Cumulative Exposure. Based on acoustical industry standards and guidelines provided by the California Department of Transportation, in areas where the ambient noise level without the project is 60 dba to 65 dba, some individuals may notice an increase in the ambient noise level of greater than 3 dba and any such increase would be a significant impact. In areas where the ambient noise level is greater than 65 dba, any increase in community noise louder than 1.5 dba or greater is considered a significant impact because the increase would contribute to an existing noise deficiency. Final August

18 Table Significance of Changes in Cumulative Exposure Ambient Level Without Project (Ldn or CNEL) Significant Impact Is Assumed To Occur if the Project Increases Ambient Levels by: < 60 dba 5.0 dba or more dba 3.0 dba or more > 65 dba 1.5 dba or more Source: U.S. Environmental Protection Agency Office of Abatement and Control, Effects Handbook-A Desk Reference to Health and Welfare Effects of, October 1979 (revised July 1981). DBA = A-weighted decibel; CNEL = community noise equivalent level; Ldn = day/night average noise level. Additionally, stationary noise associated with the operation of any facility within the project area is considered significant if it would create, maintain, cause, or allow the sound level, when measured on any other property, to exceed the allowable sound levels within Table VIBRATION IMPACTS The City of Lancaster has not adopted policies or guidelines relative to ground-borne vibration. With respect to ground-borne vibration from construction activities, the Federal Transit Administration has adopted guidelines/recommendations to limit ground-borne vibration based on the age and/or condition of the structures that are located in close proximity to construction activity. A technical discussion of construction activity-related vibration is provided in the Federal Transit Administration publication titled Transit and Vibration Impacts Assessment (May 2006). As described therein, a ground-borne vibration level of 0.2 inch-per-second peak particle velocity (PPV) should be considered as damage threshold criterion for structures deemed fragile, and a ground-borne vibration level of 0.12 inch-per-second PPV should be considered as damage criterion for structures deemed extremely fragile, such as historic buildings. With respect to structures that are considered well engineered, a ground-borne vibration damage threshold criterion of 2.0 inch-per-second PPV. The analysis has assumed a conservative threshold of 0.2 inch-per-second PPV IMPACTS AND MITIGATION MEASURES SHORT-TERM CONSTRUCTION NOISE IMPACTS Grading and construction within the area would result in temporary noise impacts to nearby noise sensitive receivers. Although, there are no specific development proposals at this time, the noise analysis is based on a conceptual plan; refer to Exhibit 3-5, District Map. The intent of the proposed project is to provide sufficient flexibility for implementation in order to be responsive to the needs of the community and to recognize economic and market conditions. The project proposes development of numerous projects throughout the project area and a buildout or horizon year of This program-level analysis presents a screening-level analysis to determine areas of potential noise impacts based on the proximity of sensitive receptors, typical noise levels associated with construction equipment, the potential for construction noise levels to interfere Final August

19 with daytime and nighttime activities, and whether construction noise audible to nearby receptors would occur outside of construction time limits specified in local ordinances. The final construction scheduling of specific projects within the DLSP area could lead to combined or collective impacts resulting from construction of more than one facility at a time. Another factor considered in assessing whether a noise impact is significant or not is the frequency with which noise levels associated with proposed project construction might exceed the established standards. If exceedance of a noise standard may happen only very rarely and/or briefly, this may not constitute a significant impact. However, this factor of noise frequency is not considered as part of this program-level impact analysis since there is currently no project specific information about the construction scenarios for individual development proposals to assess the potential frequency of proposed project noise levels. This factor would be considered as part of the separate project-level impact analysis to be conducted, as appropriate, as site-specific development within the DLSP area occurs. Based on more detailed information about proposed project construction activities and schedule, and site-specific information on the proximity of sensitive receptors, the project-level analysis may determine that impacts considered to be potentially significant and unavoidable at this program-level of review are instead significant but can be mitigated or less than significant for the project-level. ON-SITE CONSTRUCTION ACTIVITIES Ground-borne noise and other types of construction-related noise impacts would typically occur during the initial site preparation, which can create the highest levels of noise but is also generally the shortest of all construction phases. High ground-borne noise levels and other miscellaneous noise levels can be created by the operation of heavy-duty trucks, backhoes, bulldozers, excavators, front-end loaders, compactors, scrapers, and other heavy-duty construction equipment. Table 5.5-8, Maximum Levels Generated By Construction Equipment, indicates the anticipated equipment noise levels during the construction period. Typical operating cycles for these types of construction equipment may involve one or two minutes of full power operation followed by three to four minutes at lower power settings. Other primary sources of acoustical disturbance would be due to random incidents, which would last less than one minute (such as dropping large pieces of equipment or the hydraulic movement of machinery lifts). Table Maximum Levels Generated By Construction Equipment Type of Equipment Sound Levels at Maximum Engine Power with Mufflers at Indicated Distance (dba) 25 Feet 50 Feet 100 Feet 200 Feet Air Compressor Backhoe Concrete Mixer Crane, Mobile Dozer Grader Jack Hammer Loader Paver Pneumatic Tool Final August

20 Table [continued] Maximum Levels Generated By Construction Equipment Type of Equipment Sound Levels at Maximum Engine Power with Mufflers at Indicated Distance (dba) 25 Feet 50 Feet 100 Feet 200 Feet Pump Roller Saw Scraper Truck Impact Pile Driver (peak) Source: Bolt, Beranek, and Newman, Control for Buildings and Manufacturing Plants, Note: Assumes a drop-off rate of 6 dba per doubling of distance, which is appropriate for use in characterizing pointsource (such as construction equipment) sound attenuation over a hard surface propagation path. Table 5.5-9, Estimated Construction in the Project Area, provides a description of construction noise levels during specific construction stages. The average noise levels presented in Table are based on the quantity, type, and usage factors for each type of equipment that would be used during each construction stage. A reasonable worst-case assumption is that the three loudest pieces of equipment would operate simultaneously and continuously over at least one hour within a focused area of 15 yards of each other. As shown in Table 5.5-9, the average construction period noise level is expected to range from 83 dba to 92 dba at a reference distance of 25 feet. For noise levels throughout the duration of construction activity, these conservative worst-case noise levels would be reduced to account for the percentage of time that the equipment actually operates on the construction site. Based on a standard noise attenuation rate of 6 dba per doubling of distance for point sources, the worst-case construction-period noise level of 86 dba at a distance of 50 feet would be approximately 80 dba at 100 feet, and 74 dba at 200 feet. source control is the most effective method of controlling construction noise. Source controls, which limit noise, are the easiest to oversee on a construction project. Mitigation at the source reduces the problem everywhere, not just along one single path or for one receiver. The specification of equipment noise limits forces the use of modern equipment having improved engine insulation and mufflers. Refer to Mitigation Measure NOI-1. Table Estimated Construction in the Project Area Construction Stage Sound Level in dba (Leq) at Indicated Distance 25 Feet 50 Feet 100 Feet 150 Feet 200 Feet Demolition Grading/Excavation Building (Foundations, Structural, Finishing) Source: Environmental Protection Agency, from Construction Equipment and Operations, Building Equipment and Home Appliances, PB , Note: Assumes a hard surface propagation path drop-off rate of 6 dba per doubling of distance, which is appropriate for use in characterizing point-source (such as construction equipment) sound attenuation. Final August

21 As stated above, noise sensitive receptors near the construction site would, at times, experience excessive noise levels from construction activities; however excessive constructionrelated noise levels generally would occur in the daytime hours only. Lancaster Municipal Code Section (Loud, Unnecessary and Unusual s Prohibited - Construction and Building) prohibits construction or repair work on Sunday or any day between the hours of 8:00 PM and sunrise within 500 feet of an occupied dwelling, apartment, hotel, mobile home, or other place of residence. Additionally, implementation of the recommended mitigation (i.e., engine muffling, placement of construction equipment, and strategic stockpiling and staging of construction vehicles), and compliance with the Lancaster Municipal Code requirements, would serve to further reduce exposure to significant noise levels. For construction noise, a substantial noise increase can be defined as interference with activities during the day and night. One indicator that construction noise could interfere with daytime activities would be speech interference, and an indicator that construction noise could interfere with nighttime activities would be sleep interference. This analysis uses the following criteria to define the significance of potential noise impacts: Speech Interference. Speech interference is an indicator of impact on typical daytime and evening activities. A speech interference criterion, in the context of impact duration and time of day, is used to identify substantial increases in noise from temporary construction activities. peaks generated by construction equipment could result in speech interference in adjacent buildings if the noise level in the interior of the building exceeds 45 to 60 dba. 4 A typical building can reduce noise levels by 20 dba with the windows closed. 5 This noise reduction could be maintained only on a temporary basis in some cases, since it assumes windows must remain closed at all times. Assuming a 20- dba reduction with the windows closed, an exterior noise level of 70 dba (Leq) at receptors would maintain an acceptable interior noise environment of 50 dba. It should be noted that such noise levels would be sporadic rather than continuous in nature, because different types of construction equipment would be used throughout the construction process. Sleep Interference. Based on available sleep criteria data, an interior nighttime level of 35 dba is considered acceptable. 6 Assuming a 20-dBA reduction with the windows closed, an exterior noise level of 55 dba at receptors would maintain an acceptable interior noise environment of 35 dba. Since a 15-dBA reduction would occur with windows open, an exterior noise level of 50 dba (Leq) would be required to maintain an acceptable interior noise environment of 35 dba. In general, most construction noise would exceed the speech interference criterion when heavy equipment is operated within approximately 500 feet of a sensitive receptor (distance ranges between 150 and 500 feet depending on the type of equipment operated). The sleep interference criterion would be exceeded at distances closer than approximately 3,000 feet with 4 For indoor noise environments, the highest noise level that permits relaxed conversation with 100 percent intelligibility throughout the room is 45 dba. Speech interference is considered to become intolerable when normal conversation is precluded at 3 feet, which occurs when background noise levels exceed 60 dba. For outdoor environments, the highest noise level that permits normal conversation at 3 feet with 95 percent sentence intelligibility is 66 dba. 5 Environmental Protection Agency (U.S. EPA), Information on Levels of Environmental Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety (Condensed Version), Washington D.C. (EPA/ONAC 550/ ), Ibid. Final August