IV. ENVIRONMENTAL IMPACT ANALYSIS E. NOISE

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1 IV. ENVIRONMENTAL IMPACT ANALYSIS E. NOISE 1. INTRODUCTION The section analyzes the potential noise and vibration impacts that would result from the proposed project. The analysis describes the existing noise environment within the project area, estimates future noise and vibration levels at surrounding land uses resulting from construction and operation of the proposed project, identifies the potential for significant impacts, and provides mitigation measures to address significant impacts. The analysis also evaluates the compatibility of the project s proposed hotel and residential uses with the site s noise environment. In addition, an evaluation of the potential cumulative noise impacts from the proposed project and known related projects is also provided. Noise calculation and data sheets for the project are included in Appendix D of this EIR. 2. ENVIRONMENTAL SETTING a. Noise and Vibration Basics Noise is most often defined as unwanted sound. Although sound can be easily measured, the perceptibility of sound is subjective and the physical response to sound complicates the analysis of its impact on people. People judge the relative magnitude of sound sensation in subjective terms such as noisiness or loudness. Sound pressure magnitude is measured and quantified using a logarithmic ratio of pressures, the scale of which gives the level of sound in decibels (db). The human hearing system is not equally sensitive to sound at all frequencies. Therefore, to approximate this human, frequency-dependent response, the A-weighted filter system is used to adjust measured sound levels. The A-weighted sound level is expressed in dba. This scale de-emphasizes low frequencies to which human hearing is less sensitive and focuses on mid- to high-range frequencies. Although the A-weighted scale accounts for the range of people s response, and therefore, is commonly used to quantify individual event or general community sound levels, the degree of annoyance or other response effects also depends on several other perceptibility factors. These factors include: Ambient (background) sound level; Page IV.E-1

2 Magnitude of sound event with respect to the background noise level; Duration of the sound event; Number of event occurrences and their repetitiveness; and Time of day that the event occurs. People judge the relative magnitude of sound sensation by subjective terms such as loudness or noisiness. That is, a change in sound level of 3 db is considered just perceptible, a change in sound level of 5 db is considered clearly noticeable, and a change in 10 db is recognized as twice as loud. 80 In an outdoor environment, sound levels attenuate through the air as a function of distance. Such attenuation is called distance loss or geometric spreading and is based on the source configuration, line source or point source. A commonly used rule of thumb for roadway noise (line source) is that for every doubling of distance from the source, the noise level is reduced by about 3 dba at acoustically hard locations (i.e., the area between the noise source and the receptor is nearly complete asphalt, concrete, hard-packed soil, or other solid materials) and 4.5 dba at acoustically soft locations (i.e., the area between the source and receptor is earth or has vegetation, including grass). In addition, an attenuation factor of 6 dba per doubling of distance as construction noise would be generated from point sources, such as individual equipment at specific locations, as opposed to line sources such as traffic noise from roadways. For example, a sound level of 50 dba at a distance of 25 feet from the noise source would attenuate to 44 dba at a distance of 50 feet. For a line source, such as a constant flow of traffic on a roadway, the rate of sound attenuation is 3 db per doubling of distance. 81 In addition, structures (e.g., buildings and solid walls) and natural topography (e.g., hills) that obstruct the line-of-sight between a noise source and a receptor further reduce the noise level if the receptor is located within the shadow of the obstruction, such as behind a sound wall. This type of sound attenuation is known as barrier insertion loss. If a receptor is located behind the wall but still has a view of the source (i.e., line-of-sight not fully blocked), some barrier insertion loss would still occur, however to a lesser extent. Additionally, a receptor located on the same side of the wall as a noise source may actually experience an increase in the perceived noise level as the wall reflects noise back to the receptor, thereby compounding the noise. Noise barriers can provide noise level reductions ranging from approximately 5 dba Engineering Noise Control, Bies & Hansen, Caltrans, Technical Noise Supplement (TeNS), Page IV.E-2

3 (where the barrier just breaks the line-of-sight between the source and receiver) to an upper range of 20 dba with a more substantial barrier. 82 Community noise levels usually fluctuate continuously during the day. The equivalent sound level (L eq ) is normally used to describe community noise. The L eq is the equivalent steady-state A-weighted sound level that would contain the same acoustical energy as the timevarying A-weighted sound level during the same time interval. For intermittent noise sources, the maximum noise level (L max ) is normally used to represent the maximum noise level measured during the measurement. Maximum and minimum noise levels, as compared to the L eq, are a function of the characteristics of the noise source. As an example, sources such as generators have maximum and minimum noise levels that are similar to L eq since noise levels for steadystate noise sources do not substantially fluctuate. However, as another example, vehicular noise levels along local roadways result in substantially different minimum and maximum noise levels when compared to the L eq since noise levels fluctuate during pass-by events. The City of Los Angeles Noise Ordinance uses the L eq for evaluation of noise violation. To assess noise levels over a given 24-hour time period, the Community Noise Equivalent Level (CNEL) descriptor is used in land use planning. CNEL is the time average of all A-weighted sound levels for a 24-hour period with a 10 dba adjustment (upward) added to the sound levels which occur in the night (10:00 P.M. to 7:00 A.M.) and a 5 dba adjustment (upward) added to the sound levels which occur in the evening (7:00 P.M. to 10:00 P.M.). These penalties attempt to account for increased human sensitivity to noise during the quieter nighttime periods, particularly where sleep is the most probable activity. CNEL has been adopted by the State of California to define the community noise environment for development of a community noise element of a General Plan and is also used by for land use planning in the City s Noise Element of the General Plan. 83 (1) 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. With respect to ground-borne vibration, the peak particle velocity (PPV) or the root mean square (RMS) velocity, in terms of inches per second, is usually used to describe vibration amplitudes. PPV is defined as the instantaneous peak (maximum) of the vibration signal, while RMS is defined as the square root of the average of the squared amplitude of the signal. PPV is typically used for evaluating vibration levels with respect to building damage, whereas RMS is typically more Ibid. State of California, General Plan Guidelines, Page IV.E-3

4 suitable for evaluating human response. The RMS vibration velocity level can be presented in inches/second or in VdB (referenced to 1 micro-inches per second). b. Regulatory Framework Many government agencies have established noise standards and guidelines to protect citizens from potential hearing damage and various other adverse physiological and social effects associated with noise and ground-borne vibration. The project site is located in the Westwood area of the. The has adopted a number of policies, which are based in part on federal and State regulations and are directed at controlling or mitigating environmental noise effects. There are no City-adopted policies or standards that relate to ground-borne vibration, but the Federal Transit Administration (FTA), the California Department of Transportation (Caltrans), and the County of Los Angeles do have such policies and/or standards. The government agency policies that are relevant to project construction and operation are discussed below. (1) Applicable Policies and Regulations California State Government Code Section g mandates that noise elements be included as a part of city general plans and that the cities adopt comprehensive noise ordinances. The Noise Element of the City General Plan establishes CNEL guidelines for land use compatibility and includes a number of goals, objectives, and policies for land use planning purposes. The also has policies and regulations to control unnecessary, excessive and annoying noise and vibration, as cited by the Los Angeles Municipal Code (LAMC) Chapter XI, Noise Regulations. In addition, the City of L.A. CEQA Thresholds Guide (2006) provides guidelines for determining project impacts and CNEL guidelines for land use noise compatibility. These plans and regulations are further described below. (a) General Plan Noise Element The overall purpose of the Noise Element of a General Plan is to protect citizens from the harmful and annoying effects of exposure to excessive noise. Noise Element policies that relate to the proposed project include the following: 84 Policy 2.2 Enforce and/or implement applicable city, state and federal regulations intended to mitigate proposed noise producing activities, reduce intrusive noise, and alleviate noise that is deemed a public nuisance. 84 Noise Element of the Los Angeles City General Plan, adopted February 3, Page IV.E-4

5 Policy 3.1 Develop land use policies and programs that will reduce or eliminate potential and existing noise impacts. (b) Municipal Code Noise Regulation The Noise Regulation is provided in Chapter XI of the Los Angeles Municipal Code (LAMC). Section of the LAMC provides procedures and criteria for the measurement of the sound level of offending noise sources. In accordance with the LAMC, a noise level increase of 5 dba over the existing average ambient noise level at an adjacent property line is considered a noise violation. To account for people s increased tolerance for short-duration noise events, the Noise Regulation provides a 5 dba allowance for noise source occurring more than five but less than fifteen minutes in any one-hour period and an additional 5 dba allowance (total of 10 dba) for noise source occurring five minute or less in any one-hour period. 85 The LAMC indicates that in cases where the actual ambient conditions are not known or less than 50 dba, the City s presumed daytime (7:00 A.M. to 10:00 P.M.) and nighttime (10:00 P.M. to 7:00 A.M.) minimum ambient noise levels as defined in Section of the LAMC should be used. The presumed ambient noise levels for these areas as set forth in the LAMC Sections and are provided in Table IV.E-1 on page IV.E-6. For residential zoned areas, the presumed ambient noise levels are 50 dba during the day and 40 dba during the night. Section of the LAMC sets a maximum noise level for construction equipment of 75 dba at a distance of 50 feet when operated within 500 feet of a residential zone. Compliance with this standard is only required where technically feasible. 86 Section of the LAMC prohibits construction between the hours of 9:00 P.M. and 7:00 A.M. Monday through Friday, 6:00 P.M. and 8:00 A.M. on Saturday, and at any time on Sunday and national holidays. In general, the Department of Building and Safety enforces noise ordinance provisions relative to equipment and the Los Angeles Police Department enforces provisions relative to noise generated by people Los Angeles Municipal Code, Chapter XI, Article I, Section (b). In accordance with the Noise Ordinances, technically feasible means that the established noise limitations can be complied with at a project site, with the use of mufflers, shields, sound barriers, and/or other noise reduction devices or techniques employed during the operation of equipment. Page IV.E-5

6 Table IV.E-1 Presumed Ambient Noise Levels Daytime Hours (7 A.M. to 10 P.M.) dba (L eq ) Nighttime Hours (10 P.M. to 7 A.M.) dba (Leq) Zone Residential Commercial Manufacturing (M1, MR1 and MR2) Heavy Manufacturing (M2 and M3) Source: LAMC, Section (c) Guidelines for Noise Compatible Land Use (CNEL Guidelines) The has adopted local guidelines based, in part, on the community noise compatibility guidelines established by the State Department of Health Services for use in assessing the compatibility of various land use types with a range of noise levels. These guidelines are set forth in the City of L.A. CEQA Thresholds Guide (2006) in terms of the CNEL. CNEL guidelines for specific land uses are classified into four categories: (1) normally acceptable, (2) conditionally acceptable, (3) normally unacceptable, and (4) clearly unacceptable. As shown in Table IV.E-2 on page IV.E-7, a CNEL value of 70 dba is the upper limit of what is considered a conditionally acceptable noise environment for multi-family residential and hotel uses, although the upper limits of what is considered clearly unacceptable for multi-family residential and hotel uses are set at 70 dba CNEL and 80 dba CNEL, respectively. 87 New development should generally be discouraged within the unacceptable category. However, if new development does proceed, a detailed analysis of the noise reduction requirements must be made and needed noise insulation features included in the design. (2) Ground-Borne Vibration Potential impacts due to ground-borne vibration include: human annoyance, building damage, and potential interference with other sensitive uses (i.e., operating rooms and vibration sensitive equipment). The currently does not have any adopted policies or guidelines relative to ground-borne vibration. As such, the following is a summary of Los Angeles County, Caltrans, and FTA ground-borne vibration policies and guidelines. 87 City of L.A. CEQA Thresholds Guide, Section I.2, Page IV.E-6

7 Table IV.E-2 Land Use Compatibility for Community Noise Community Noise Exposure CNEL, dba Normally Conditionally Normally Clearly Land Use Acceptable Acceptable Unacceptable Unacceptable Single-Family, Duplex, Mobile Homes 50 to to to 75 Above 70 Multi-Family Homes 50 to to to 75 Above 70 Schools, Libraries, Churches, Hospitals, 50 to to to 80 Above 80 Nursing Homes Transient Lodging Motels, Hotels 50 to to to 80 Above 80 Auditoriums, Concert Halls, 50 to 70 Above 65 Amphitheaters Sports Arena, Outdoor Spectator Sports 50 to 75 Above 70 Playgrounds, Neighborhood Parks 50 to to 75 Above 72 Golf Courses, Riding Stables, Water 50 to to 80 Above 80 Recreation, Cemeteries Office Buildings, Business and 50 to to 77 Above 75 Professional Commercial Industrial, Manufacturing, Utilities, Agriculture 50 to to 80 Above 75 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 insulation features included in the design. Clearly Unacceptable: New construction or development should generally not be undertaken. Source: City of L.A. CEQA Thresholds Guide, With respect to human annoyance, the Los Angeles County Noise Regulation (LA County Municipal Code Section ) sets a presumed perception threshold of 0.01 inches per second RMS, but this applies to ground-borne vibrations from long-term operations activities (applicable to potential annoyance), not construction. Studies from Caltrans and FTA shows vibration velocity levels greater than 0.04 inches per second peak particle velocity (PPV) are distinctly perceptible to human and become strongly perceptible at 0.10 inches per second PPV Caltrans Transportation- and Construction-Induced Vibration Guidance Manual, Table 20, 2004 Page IV.E-7

8 With respect to potential building damage (primarily from construction activities), the FTA and Caltrans have 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 Section 12.2 of the FTA s Transit Noise and Vibration Impacts Assessments. As described therein, a ground-borne vibration level of 0.2 inch-per-second 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 threshold criterion for structures deemed extremely fragile, such as historic buildings. Caltrans technical publication, Transportation- and Construction-Induced Vibration Guidance Manual (June 2004) recommends vibration damage potential threshold criteria (for transient sources) of 0.5 inch-per-second PPV for older residential structures, 1.0 inch-per-second PPV for newer residential structures, and 2.0 inch-per-second PPV for modern industrial/ commercial buildings. 89 In addition to potential human annoyance and building damage from vibration impacts, ground-borne vibration could also have impacts to vibration sensitive equipment (e.g., high power microscope) and vibration sensitive function (e.g., hospital operating room). Floor vibration criteria/ guidelines for hospital uses, such as operating rooms and vibration sensitive equipment are recommended by ASHRAE (American Society of Heating, Refrigerating and Air- Conditioning Engineers). The criteria given by AHSRAE are based on guidelines specified by ANSI Standard S3.29 and by ISO Standard and are widely utilized by the building designers. Per ASHRAE, the vibration limits for hospital operating room is inches per second RMS. A medical building is located at Wilshire Boulevard, approximately 90 feet to the east of the project site. The closest hospital, UCLA Medical Center, is located approximately 1,800 feet to the north of the project site. c. Existing Conditions (1) Noise-Sensitive Receptors Some land uses are considered more sensitive to noise than others due to the amount of noise exposure and the types of activities typically involved at the receptor location. The City of L.A. CEQA Thresholds Guide (2006) states that noise sensitive uses include residences, schools, motels and hotels, libraries, religious institutions, hospitals, nursing homes, and parks, which are generally more sensitive to noise than commercial and industrial land uses. Existing noise sensitive uses within several hundred feet of the project site are shown in Figure IV.E-1 on page IV.E-9, and include the following: 89 Caltrans Transportation- and Construction-Induced Vibration Guidance Manual, Table 19, 2004 Page IV.E-8

9 y yle Ga rn bu ey W Tivert on A venue R4 Hilgard Avenue We ybu rn Av enu e on nd le G ue en Av e ac Pl e Driv ok dbro Lin R3 ue en Av nue Ave ter s e h Roc Noise Monitoring Locations N Scale in approximate feet ue ven n A d var ule Bo ale ue en Av ue ven th A r o lw Wel dv n ra te Ve Vibration Sensitive Locations ue ven n A o t h As Mi Project Site ndo d oo stw We ue en Av R2 LEGEND Gle an ter Ve R1 vard oule B e hir Wils Noise Sensitive Locations ue en Av n Ki s s ro ue en Av 600 Feet Source: PCR Services Corporation, 2008; Google Earth, Figure IV.E-1 Existing Noise and Vibration Sensitive Uses and Noise Measurement Locations Wilshire Gayley Development Project

10 South of Project Site: The nearest noise sensitive use, multi-family residential, is located south of Wilshire Boulevard along Midvale Avenue and approximately 500 feet south of the proposed project site. North and East of Project Site: There are multi-family residential uses that are separated from the project site by intervening buildings located along Gayley Avenue and Wilshire Boulevard and approximately 1,200 feet north and east of the proposed project site, respectively. (2) Ambient Noise Levels The predominant noise source surrounding the project site is roadway noise from auto traffic on Lindbrook Drive and Gayley Avenue to the east and Wilshire Boulevard to the south. Secondary noise sources include existing general commercial and retail-related activities, loading dock/delivery truck activities, ambulance and police sirens, trash compaction, and refuse service activities. Ambient noise measurements were made at four locations, representing the nearby land uses in the vicinity of the project site as indicated on Figure IV.E-1. Long-term (24-hour) measurements were conducted at noise monitoring location R1 (proposed project site) and shortterm (15-minute) measurements were recorded at noise monitoring locations R2 through R4. The ambient noise measurements were made in accordance with the City s standards, which require ambient noise to be measured over a period of at least 15 minutes. 90 Ambient sound measurements were conducted from Wednesday, August 20, through Thursday, August 21, 2008, to characterize the existing noise environment in the project vicinity. The ambient noise measurements were conducted using the Larson-Davis 820 Precision Integrated Sound Level Meter (SLM). The Larson-Davis 820 SLM is a Type 1 standard instrument as defined in the American National Standard Institute (ANSI) S1.4. All instruments were calibrated and operated according to the applicable manufacturer specification. The microphone was placed at a height of five feet above the local grade, at the following locations, which are graphically depicted on Figure IV.E-1: Measurement Location R1: This measurement location represents the existing environment of the proposed project site. The noise measuring device (sound level meter) was placed on the site s southwestern boundary near Wilshire Boulevard. 90 Los Angeles Municipal Code, Section Page IV.E-10

11 Measurement Location R2: This measurement location represents the noise environment of the nearest noise-sensitive receptor, approximately 500 feet south of the proposed project site. The sound level meter was placed on the southwest corner of Ashton Avenue and Midvale Avenue. Measurement Location R3: This measurement location represents the existing noise environment of the nearest multi-family residential uses, approximately 1,200 feet east of the project site. The sound level meter was placed in front of the multi-family residential tower near Wilshire Boulevard. Measurement Location R4: This measurement location represents the existing noise environment of the nearest multi-family residential uses, approximately 1,200 feet north of the project site. The sound level meter was placed in front of the multifamily residential units near Gayley Avenue. A summary of noise measurement data is provided in Table IV.E-3 on page IV.E-12. As shown in Table IV.E-3, the existing ambient noise levels range from 61 dba to 73 dba (hourly L eq ) at the nearby noise sensitive receptors, R2 through R4. These ambient noise levels exceed the City s presumed ambient noise levels (specified in the LAMC Sec Table II and indicated in Table IV.E-1 on page IV.E-6). In addition, the measured CNEL at the project site was 73 CNEL at the southwest project boundary. Based on the community noise/land use compatibility criteria provided in Table IV.E-2, this noise environment is generally considered normally unacceptable for multi-family residential uses and hotel uses. In accordance with City requirements, a detailed noise reduction analysis of the project s proposed residential units must be conducted and required noise insulation features must be included in the design for any new residential development. To further characterize the area s noise environment, the CNEL noise levels generated by existing traffic on local roadways was calculated using a noise prediction model developed based on calculation methodologies provided in the Caltrans Technical Noise Supplement (TeNS) document and traffic data provided by the project s traffic consultant. The roadway noise calculation procedures provided in the Caltrans TeNS are consistent with Federal Highway Administration RD roadway noise prediction methodologies. This methodology allows for the definition of roadway configurations, barrier information (if any), and receiver locations. A model calibration test was performed to establish the noise prediction model's accuracy. The road segment included in the calibration test was Midvale Avenue (Receptor Location R2). At the noted location, a minimum of 15-minute noise recording was made concurrent with logging of actual traffic volumes and auto fleet mix (i.e., standard automobile, medium duty truck, or heavy duty truck). The traffic counts were entered into the noise model along with the observed speed, lane configuration, and distance to the roadway to calculate the traffic noise levels. The results of the traffic noise model calibration are provided in Table IV.E-4 on page IV.E-13. As indicated, the Page IV.E-11

12 Table IV.E-3 Summary of Ambient Noise Measurements Receptor Location R1 Long Term Noise Measurements Southwest Property Line near Wilshire Boulevard R2 Short Term Noise Measurements Midvale Avenue multi-family residential uses R3 Short Term Noise Measurements Wilshire Boulevard multi-family residential uses R4 Short Term Noise Measurements Gayley Avenue multi-family residential uses Measurement Date / Time of Day 8/20/08 Wednesday (9:00 A.M.) 8/21/08 Thursday (9:00 A.M.) 8/20/08 Wednesday (10:00 A.M. to 12:00 P.M.) 8/20/08 Wednesday (10:00 A.M. to 12:00 P.M.) 8/20/08 Wednesday (10:00 A.M. to 12:00 P.M.) Measured Ambient Noise Levels, a (dba) Nighttime (10 P.M. to 7 A.M.) Hourly L eq Daytime (7 A.M. to 10 P.M.) Hourly L eq 24-Hour Average, CNEL b N/A N/A 73 N/A N/A 61 N/A N/A Notes: N/A - noise measurements are short period readings Not Applicable for CNEL calculations. Receptor Locations are shown on Figure IV.E-1. a b Detailed measured noise data, including hourly L eq levels, are included in Appendix D. Calculated from the 24-hour measurement. Source: PCR Services Corporation, noise model results are within less than 1 dba of the measured noise levels, which is within the industry standard tolerance of the noise prediction model. Therefore, the project specific traffic noise prediction model is considered accurate and specific to the project physical settings and conditions. The traffic noise prediction model calculates the 24-hour CNEL noise levels based on specific information including; Average Daily Traffic Volume (ADT), percentages of day, evening and nighttime traffic volumes relative to ADT, vehicle speed and distance between the noise receptor and the roadway. Vehicle mix/distribution information used in the noise calculation is shown in Table IV.E-5 on page IV.E-14. As indicated in Table IV.E-6 on page IV.E-15, the calculated CNEL for the analyzed roadway segments as a result of existing traffic volumes ranged from 62.2 dba CNEL to 73.3 dba CNEL at a distance of 25 feet based on surface-street traffic volume only. As shown therein, noise levels at the nearest sensitive receptors to each analyzed roadway segment exceed normally acceptable noise levels at all residential areas, i.e., 65 dba or lower, except at residential uses along Gayley Avenue and Glendon Avenue. Page IV.E-12

13 Table IV.E-4 Traffic Noise Model Calibration Results Traffic Counts during noise readings, 15-minutes Measured Traffic Noise Levels, L eq (dba) Project Traffic Noise Model Predicted Noise Levels, L eq (dba) Difference between Predicted and Measured Levels, dba Road Segment/ Noise Measurements Locations Autos Medium Trucks a Heavy Trucks b Midvale Avenue / R Wilshire Boulevard / R Gayley / R a b Medium Truck 2 axle trucks based on field observations. Heavy Truck 3 or more axles trucks and buses based on field observations. Source: PCR Services Corporation, (3) Vibration-Sensitive Receptor Locations Typically, ground-borne vibration generated by man-made activities (i.e., rail and roadway traffics, mechanical equipment and typical construction equipment) diminishes rapidly as the distance from the source of the vibration becomes greater. FTA uses a screening distance of 100 feet and 50 feet for vibration sensitive buildings (e.g., hospital with vibration sensitive equipment) and residential uses, respectively. With respect to structures, vibration-sensitive receptors generally include historic buildings, buildings in poor conditions (fragile structures), and uses that require precision instruments (e.g., operating rooms or scientific laboratories). No historic buildings and/or fragile buildings are currently present within 100 feet of the project site that may be affected by the proposed project. However, the medical building located at Wilshire Boulevard, approximately 90 feet to the east of the project site could use vibration sensitive equipment or have vibration sensitive functions such as operating rooms within the building. While it has not been confirmed that there are vibration sensitive uses within this building, out of an abundance of caution the possibility is being considered in the analysis of construction activities (e.g., demolition, excavation, etc.). The nearest residential uses are approximately 500 feet from the proposed project site. At this distance the project construction induced ground vibration would not be anticipated. (4) Existing Ground-Borne Vibration Environment Based on field observations, the only source of ground-borne vibration in the project vicinity is vehicular travel (including refuse trucks, delivery trucks, and transit buses) on local roadways. According to FTA technical study, typical road traffic induced vibration levels are unlikely to be perceptible by people. In part, FTA indicates it is unusual for vibration from Page IV.E-13

14 Table IV.E-5 Vehicle Mix for Traffic Noise Model Percent of ADT, (%) Vehicle Type Daytime hours (7 A.M. to 7 P.M.) Evening Hours (7 P.M. to 10 P.M.) Nighttime Hours (10 P.M. to 7 A.M.) Total Automobile Medium Truck a Heavy Truck b a b Medium Truck 2 axle trucks based on field observations. Heavy Truck 3 or more axles trucks and buses based on field observations. Source: Project Traffic Consultant, Fehr & Peers Transportation Consultants, traffic including buses and trucks to be perceptible, even in location close to major roadways. 91 Therefore, FTA published vibration data are utilized in describing the existing ground vibration environment in the vicinity of the project site. As the project site is located within 50 feet of two major roadways; Wilshire Boulevard and Gayley Avenue; it is likely the site is exposed to ground vibration level of inches per second RMS. 92 This vibration level is considered well below the perception threshold of 0.01 inches per second (RMS) as defined by Los Angeles County Noise Regulation (discussed above). 3. PROJECT IMPACTS a. Methodology (1) On-Site Construction Noise On-site construction and construction trucks staging and hauling route noise impacts are evaluated by determining the noise levels generated by the different types of construction activity, calculating the construction-related noise level at nearby sensitive receptor locations, and comparing these construction-related noise levels to existing ambient noise levels (i.e., noise levels without construction noise). More specifically, the following steps were undertaken to calculate construction-period noise impacts: Federal Transit Administration "Transit Noise and Vibration Impact Assessment, Chapter 7, A typical bus or truck can produce a ground vibration level of to inches per second RMS at a distance of 50 feet. (Federal Transit Administration, Transit Noise and Vibration Impact Assessment, April 1995) Page IV.E-14

15 Table IV.E-6 Predicted Existing Vehicular Traffic Noise Levels Adjacent Land Use Existing Noise Exposure Compatibility a Category Predicted Existing CNEL (dba) at Referenced Distances from Roadway Right-of-Way Adjacent 25 feet 50 feet Roadway Segment Gayley Avenue North of Kinross Avenue Residential Conditionally Acceptable Between Kinross Avenue and Lindbrook Drive Commercial Normally Acceptable Between Lindbrook Drive and Wilshire Boulevard Commercial Normally Acceptable Midvale Avenue South of Wilshire Boulevard Residential Normally Acceptable Glendon Avenue North of Lindbrook Drive Commercial Normally Acceptable Between Lindbrook Drive and Wilshire Boulevard Commercial Normally Acceptable South of Wilshire Boulevard Residential Normally Acceptable Westwood Boulevard North of Lindbrook Drive Residential Conditionally Acceptable Between Lindbrook Drive and Wilshire Boulevard South of Wilshire Boulevard Lindbrook Drive Between Gayley Avenue and Westwood Boulevard Between Westwood Boulevard and Glendon Avenue East of Glendon Avenue Commercial Normally Acceptable Residential Conditionally Acceptable Commercial Normally Acceptable Commercial Normally Acceptable Residential Conditionally Acceptable Kinross Avenue East of Gayley Avenue Commercial Normally Acceptable Wilshire Boulevard Between Veteran Avenue and Conditionally Commercial Gayley Avenue Acceptable Between Gayley Avenue and Conditionally Commercial Westwood Boulevard Acceptable Between Westwood Boulevard and Glendon Avenue Commercial Conditionally Acceptable East of Glendon Avenue Residential Normally Unacceptable a Based on noise levels at 25 feet distance from the roadway. Source: PCR Services Corporation, Page IV.E-15

16 1. Ambient noise levels at surrounding sensitive receptor locations were estimated based on field measurement data (see Table IV.E-3 on page IV.E-12) and/or presumed noise level as stated in the LAMC, Section (see Table IV.E-1 on page IV.E-6); 2. Typical noise levels for each type of construction equipment were obtained from the Federal Highway Administration s (FHWA) Roadway Construction Noise Model; 3. Distances between construction site locations (noise source) and surrounding sensitive receptors were measured using on line mapping applications and project s site plans; 4. The construction noise level was then calculated for sensitive receptor locations based on the standard point source noise-distance attenuation factor of 6.0 dba for each doubling of distance; and 5. The resulting noise level was compared to the construction noise significance thresholds identified below. (2) Off-Site Construction Noise Off-site construction noise impacts were evaluated by determining the noise generated by construction-related trucks traveling off-site and comparing with the existing ambient noise levels. The off-site construction truck noise levels were calculated based on the estimated maximum volume of trucks per hour using Caltrans traffic noise prediction methodology in the Technical Noise Supplement (TeNS). Noise attributable to project s trucks was calculated and compared to existing ambient noise levels to determine significance. (3) Operation Noise (a) Off-Site Noise Sources (Roadway Traffic) Roadway noise impacts were evaluated using TeNS methodology. This methodology allows the user to define roadway configurations, barrier information (if any), and receptor locations. Traffic noise levels were calculated for roadway segments with sensitive receptors at distances of 25 feet and 50 feet from the edge of the roadway. Roadway-noise attributable to project development future with project was calculated and compared to baseline noise levels that would occur under the future without project condition to determine significance. (b) On-Site Noise Sources Stationary point-source noise impacts were evaluated by identifying the noise levels generated by outdoor stationary noise sources such as building mechanical/electrical equipment, Page IV.E-16

17 loading dock and trash/recycling areas, parking facility, outdoor pool facility, and rooftop helipad, estimating the noise level from each noise source at surrounding residential property locations, and comparing such noise levels to ambient noise levels to determine significance. Similar to the on-site construction noise analysis, the following steps were undertaken to calculate operation-period noise impacts: 1. Typical noise levels for on-site noise sources were obtained from published data or measured data from previous projects; 2. Distances between noise source location and surrounding sensitive receptors were measured using online mapping applications and project s site plans; 3. The noise level was then calculated for sensitive receptor locations based on the standard point source noise-distance attenuation factor of 6.0 dba for each doubling of distance and barrier insertion loss (from intervening buildings); and 4. The resulting noise level was compared to the ambient noise levels at surrounding sensitive receptor locations. (4) Ground-Borne Vibration (During Project Construction and Operations) Ground-borne vibration impacts were evaluated by identifying potential vibration sources, measuring the distance between vibration sources and surrounding structure locations, and making a significance determination based on the thresholds discussed below. b. Thresholds of Significance (1) Appendix G CEQA Guidelines In accordance with Appendix G to the State CEQA Guidelines, the project could have a significant impact on noise if it would result in: a) Exposure of persons to or generation of noise levels in excess of standards established in the local general plan or noise ordinance, or applicable standards of other agencies; b) Exposure of persons to or generation of excessive groundborne vibration or groundborne noise levels; c) A substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project; Page IV.E-17

18 d) A substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the project; e) 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, would the project expose people residing or working in the project area to excessive noise levels; f) For a project within the vicinity of a private airstrip, would the project expose people residing or working in the project area to excessive noise levels. As discussed in the Initial Study, which is contained in Appendix A of this EIR, and in Section VI.F, Effects Found To Be Less Than Significant, the project would have no impact with respect to e. and f. As such no further analysis of this topic is necessary. (2) CEQA Thresholds Guide (a) Construction Noise The City of L.A. CEQA Thresholds Guide (2006) provides specific guidance for assessing a project's impacts. The following factors are set forth therein to determine on a case-by-case basis whether the proposed project would have a potential impact: Construction activities lasting more than one day would exceed existing ambient exterior noise levels by 10 dba or more at a noise-sensitive use; Construction activities lasting more than 10 days in a three-month period would exceed existing ambient exterior noise levels by 5 dba or more at a noise-sensitive use; or Construction activities would exceed the ambient noise level by 5 dba at a noisesensitive use between the hours of 9:00 P.M. and 7:00 A.M. Monday through Friday, before 8:00 A.M. or after 6:00 P.M. on Saturday, or at anytime on Sunday. (b) Construction Vibration The does not have a significance threshold to assess vibration impacts during construction. Thus, the Caltrans and ASHRAE standards described earlier are used to evaluate potential impacts related to project construction. All structures that are located within the immediate vicinity of the project site are considered well engineered (as opposed to fragile or extremely fragile ); therefore, impacts relative to ground-borne vibration would be considered significant if: Page IV.E-18

19 Project construction activities would cause ground-borne vibration levels to exceed 2.0 inches per second (PPV) at the nearest off-site building. Project construction activities would cause ground-borne vibration levels to exceed inches per second (RMS) at the Medical Building located at Wilshire Boulevard. (c) Operation Noise The City of L.A. CEQA Thresholds Guide (2006) provides specific guidance for assessing a project's impacts. The following factors are set forth in therein to determine on a case-by-case basis whether the proposed project would have a potential impact: The Proposed Project mobile noise source (i.e., off-site traffic) would cause ambient noise levels to increase by 5 dba CNEL or more and the resulting noise falls on a land use within an area categorized as either normally acceptable or conditionally acceptable (see Table IV.E-2 on page IV.E-7 for description of these categories); or The Proposed Project mobile noise source (i.e., off-site traffic) would cause ambient noise levels to increase by 3 dba CNEL or more and the resulting noise falls on a land use within an area categorized as either normally unacceptable or clearly unacceptable. Project-related operational on-site noise sources (i.e., non-roadway), such as outdoor building mechanical/electrical equipment and loading dock/refuse collection, increase ambient noise level by 5 dba, thus causing a violation of the City Noise Ordinance. The City of L.A. CEQA Thresholds Guide (2006) does not recommend a significant threshold for interior residential noise levels. However, the Building Code requires that interior noise level attributable to exterior noise shall not exceed 45 dba (CNEL) in residential and hotel units (habitable room). Therefore, a significant interior noise impact would result if: Proposed hotel and residential uses are exposed to an exterior noise level of greater than 65dBA CNEL for outdoor living areas (excluding balconies) or an interior noise level of greater than 45 dba CNEL. (d) Ground-Borne Vibration from Project Operations The does not have a specific significance threshold to assess vibration impacts due to long-term project operations. Thus, the County of Los Angeles standard Page IV.E-19

20 for human perception described earlier is used to evaluate potential impacts related to project operations. Therefore, impacts relative to ground-borne vibration would be considered significant if the following future event were to occur: Project operational activities generate a ground-borne vibration level equivalent to or exceeding the perception threshold of 0.01 inches per second (RMS) as defined by Los Angeles County Noise Regulation (discussed above) at any sensitive receptor. c. Project Design Features The following project features to be implemented by the Applicant during the project s construction and operation have a potential to influence project-related noise characteristics, and therefore, were taken into account during the analysis of potential project impacts. (1) Project Construction The project contractor(s) would equip all construction equipment, fixed or mobile, with properly operating and maintained noise mufflers, consistent with manufacturers standards. The project construction haul route would access the site via Wilshire Boulevard from the 405 Freeway, to avoid noise sensitive uses. In accordance with LAMC requirements, construction hours for exterior construction and hauling activities would not occur outside the hours of 7:00 A.M. and 9:00 P.M., Monday through Friday, and 8:00 A.M. and 6:00 P.M. on Saturday. (2) Project Operations All building mechanical and electrical equipment would be located within the building on the 3 rd level, which would provide noise shielding to the exterior. In addition, the project s mechanical equipment would also be designed to meet the requirements of LAMC, Chapter XI, Section , which prohibits increasing the ambient noise level by more than 5 dba for adjoining sensitive uses, such as the residential receptors within the building. All loading dock and trash/recycling areas would be fully or partially enclosed such that the line-of-sight between these noise sources and any adjacent noise sensitive land use would be obstructed. Page IV.E-20

21 d. Analysis of Project Impacts (1) Construction Noise Noise impacts from construction activities are generally a function of the noise generated by construction equipment, the equipment location, the sensitivity of nearby land uses, and the timing and duration of the noise-generating activities. Construction activities at the project site would include four stages: (1) demolition; (2) site grading; (3) foundation; and (4) building construction. Each stage involves the use of different kinds of construction equipment and, therefore, has its own distinct noise characteristics. Demolition typically involves the use of loader, concrete saw, water truck, and dozer. Site grading typically involves the use of earth moving equipment, such as loader, excavator, crane, and drill rig. Construction of building foundation typically involves the use of concrete mixer truck, crane, backhoe, concrete pump, and loader. Building construction typically involves the use of concrete mixer truck, forklift, air compressor, crane, and generator. The proposed project would be constructed using typical construction techniques; no blasting or impact pile driving would be used. Construction of the proposed project is estimated to last approximately 25 months. Construction noise impacts would be the same for Option 1 and Option 2, as the noise components of the overall development would be the same for both project options. Therefore, the following analysis is for both Option 1 and Option 2. (a) On-Site Construction Activities Option 1 and Option 2 Project construction would require the use of mobile heavy equipment with high noise level characteristics. Individual pieces of construction equipment that would be used for project construction produce maximum noise levels of 74 dba to 81 dba at a reference distance of 50 feet from the noise source, as shown in Table IV.E-7 on page IV.E-22. These maximum noise levels would occur when equipment is operating under full power conditions or during impact activities, such as jack hammering or sawing. However, equipment used on construction sites often operates under less than full power conditions, or part power. To more accurately characterize construction-period noise levels, the average (Hourly L eq ) noise level associated with each construction stage is calculated based on the quantity, type, and usage factors for each type of equipment that would be used during each construction stage and are typically attributable to multiple pieces of equipment operating simultaneously. The construction noise modeling does not include effective noise control devices (i.e., mufflers, lagging, and/or motor enclosures). Page IV.E-21

22 Table IV.E-7 Construction Equipment Noise Levels Typical Noise Level at 50 feet Equipment Estimated Usage Factor (%) from Equipment, dba (L max ) Air Compressor Backhoe Concrete Mixer Truck Concrete Pump Concrete Saw Crane Dozer Drill Rig Dump/Haul Truck Excavator Forklift Generator Loader Water Truck Source: FHWA Roadway Construction Noise Model, Construction activities would occur within the project site. As such, the individual pieces of construction equipment are considered as a point source for noise since the equipment would be moving within the site. Therefore, as indicated above, according to Caltrans Technical Noise Supplement, considering the construction equipment as a point source, the attenuation factor is 6 dba per doubling of distance for hard sites. 93 Using the conservative industry standard sound attenuation rate of 6 db per doubling of distance for point sources (e.g., construction equipment), the worst-case construction-period noise levels were estimated at the noise sensitive receptors by phase of construction activity. 94 A summary of noise level increases by receptor location and phase of construction activity is 93 The CalTrans Technical Noise Supplement (October 1998) defines hard sites as sites with a reflective surface between the source and the receiver such as parking lots or smooth bodies of water. No excess ground attenuation is assumed for these sites and the changes in noise with distance (drop-off rate) are simply the geometric spreading of the line source (traffic on roadway) or 3 dba per doubling distance. The technical study also states 6 dba attenuation per doubling distance for a point source (stationary noise source). In comparison, soft sites are sites that have an absorptive ground surface such as soft dirt, grass or scattered bushes and trees. An excess ground attenuation value of 1.5 dba per doubling distance is normally assumed. When added to the geometric spreading results in an overall drop-off rate of 4.5 dba per doubling distance for a line source (traffic on roadway). The technical study also states 7.5 dba attenuation per doubling distance for a point source (stationary noise source). 94 Caltrans Technical Noise Supplement, October Page IV.E-22