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HomeMy WebLinkAbout09_Sec4.4_NoiseVibration_web.pd 4.4 Noise and Vibration 4.4NOISE AND VIBRATION This section describes the potential for impacts related to noise and ground-borne vibration resulting from implementation of the proposed project. The primary noise concerns related to the proposed project would result from the increased vehicular traffic in the MEIR Study Area, associated noise levels associated with project construction, and the associated noise levels experienced by nearby sensitive receptors, including the Larkspur Landing Hotel, located on Gateway Boulevard approximately 2,000 feet to the northwest of the MEIR Study Area, and the proposed childcare center located on Allerton Avenue that is part of the proposed project. Specifically, this section evaluates the site-specific environmental impacts related to substantial temporary and/or permanent increase in ambient noise levels in the vicinity of the proposed project; exposure of residents or businesses to excessive noise levels or ground-borne vibration; and whether this exposure would be in excess of standards established in the East of 101 Area Plan and the City?s Noise Ordinance, or any other applicable standards. Preparation of this section used data from various sources, including the proposed 2006 FMPU, the South San Francisco Municipal Code (SSFMC), the City of South San Francisco General Plan prepared by Dyett & Bhatia and adopted in October 1999; the East of 101 Area Plan prepared by Brady and Associates and adopted in July 1994; the San Mateo County Airport Land Use Commission FAA Height and Noise Contours, 2000; the Genentech Existing Conditions Report prepared by Nelson/Nygaard Consulting Associates and Fehr & Peers Transportation Consultants in April 2005, and the traffic study prepared for the 2006 FMPU. Full bibliographic entries for all reference materials are provided in Section 4.4.4 (References). No comment letters related to noise and vibration were received in response to the December 9, 2005 Revised Notice of Preparation (NOP) circulated for the proposed project. In addition, no comments were received at the public scoping meeting held January 17, 2006. The NOP and comment letters are included in Appendix A of this MEIR. 4.4.1Existing Conditions Fundamentals of Sound and Environmental Noise Sound is technically described in terms of amplitude (loudness) and frequency (pitch). The standard unit of sound amplitude measurement is the decibel (dB). The decibel scale is a logarithmic scale that describes the physical intensity of the pressure vibrations that make up any sound. The pitch of the sound is related to the frequency of the pressure vibration. Because the human ear is not equally sensitive to a given sound level at all frequencies, a special frequency-dependent rating scale has been devised to relate noise to human sensitivity. The A-weighted decibel scale (dBA) provides this compensation by discriminating against frequencies in a manner approximating the sensitivity of the human ear. Noise, on the other hand, is typically defined as unwanted sound. A typical noise environment consists of a base of steady ?background? noise that is the sum of many distant and indistinguishable noise sources. Superimposed on this background noise is the sound from individual local sources. These can 4.4-1 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis vary from an occasional aircraft or train passing by to virtually continuous noise from, for example, traffic on a major highway. Table 4.4 1 (Representative Environmental Noise Levels) lists representative noise levels for the environment. Table 4.4-1 Representative Environmental Noise Levels Common Outdoor Activities Noise Level (dBA) Common Indoor Activities —110— Rock Band Jet Fly-over at 100 feet —100— Gas Lawnmower at 3 feet —90— Food Blender at 3 feet Diesel Truck going 50 mph at 50 feet —80— Garbage Disposal at 3 feet Noisy Urban Area during Daytime Gas Lawnmower at 100 feet —70— Vacuum Cleaner at 10 feet Commercial Area Normal Speech at 3 feet Heavy Traffic at 300 feet —60— Large Business Office Quiet Urban Area during Daytime —50— Dishwasher in Next Room Quiet Urban Area during Nighttime —40— Theater, Large Conference Room (background) Quiet Suburban Area during Nighttime —30— Library Quiet Rural Area during Nighttime Bedroom at Night, Concert Hall (background) —20— Broadcast/Recording Studio —10— Threshold of Human Hearing —0— Threshold of Human Hearing SOURCE: California Department of Transportation 1998 Several rating scales have been developed to analyze the adverse effect of community noise on people. Because environmental noise fluctuates over time, these scales consider that the effect of noise upon people is largely dependent upon the total acoustical energy content of the noise, as well as the time of day when the noise occurs. The rating scales of L, L, and L are measures of ambient noise, while eqminmax and CNEL are measures of community noise. Each is applicable to this analysis and defined as the L dn follows: L, the equivalent energy noise level, is the average acoustic energy content of noise over any chosen eq exposure time. The L is the constant noise level that would deliver the same acoustic energy to eq the ear as the actual time-varying noise over the same exposure time. L does not depend on the eq time of day during which the noise occurs. 4.4-2 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration L, the day-night average noise level, is a 24-hour average L with a 10 dBA ?penalty? added to noise dn eq during the hours of 10:00 .. to 7:00 .. to account for increased nighttime noise sensitivity. PMAM Because of this penalty, the L would always be higher than its corresponding 24-hour L (e.g., a dneq constant 60 dBA noise over 24 hours would have a 60 dBA L, but a 66.4 dBA L). eqdn CNEL, the community noise equivalent level, is an L with an additional dBA ?penalty? for the evening dn hours between 7:00 .. and 10:00 .. PMPM L, the minimum instantaneous noise level experienced during a given period of time. min L, the maximum instantaneous noise level experienced during a given period of time. max Noise environments and consequences of human activities are usually well represented by median noise levels during the day or night, or over a 24-hour period. Environmental noise levels are generally considered low when the CNEL is below 60 dBA, moderate in the 60 to 70 dBA range, and high above 70 dBA. Examples of low daytime noise levels are isolated, natural settings that can provide noise levels as low as 20 dBA and quiet, suburban, residential streets that can provide noise levels around 40 dBA. Noise levels above 45 dBA at night can disrupt sleep. Examples of moderate-level noise environments are urban residential or semi-commercial areas (typically 55 to 60 dBA) and commercial locations (typically 60 dBA). People may consider louder environments adverse, but most will accept the higher noise levels associated with more noisy urban residential or residential-commercial areas (60 to 75 dBA) or dense urban or industrial areas (65 to 80 dBA). When evaluating changes in 24-hour community noise levels, a difference of 3 dBA is a barely perceptible increase to most people (Hendriks 1998). A 5 dBA increase is readily noticeable, while a difference of 10 dBA would be perceived as a doubling of loudness. Noise levels from a particular source decline as distance to the receptor increases. Other factors, such as the weather and other reflecting or shielding factors, also help intensify or reduce the noise level at any given location. A commonly used rule of thumb for roadway noise 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 unpacked earth or has vegetation, including grass). Noise from stationary or point sources is reduced by about 6 to 7.5 dBA for every doubling of distance at acoustically hard and soft locations, respectively. Noise levels may also be reduced by intervening structures; generally, a single row of buildings between the receptor and the noise source reduces the noise level by about 5 dBA, while a solid wall or berm reduces noise levels by 5 to 10 dBA. The manner in which older homes in California were constructed (approximately 30 years old or older) generally provides a reduction of exterior-to-interior noise levels of about 20 to 25 dBA with closed windows. The exterior-to-interior reduction of newer units is generally 30 dBA or more. 4.4-3 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Fundamentals of Environmental Groundborne Vibration Vibration is sound radiated through the ground. The rumbling sound caused by the vibration of room surfaces is called groundborne noise. The ground motion caused by vibration is measured as particle velocity in inches per second and, in the U.S., is referenced as vibration decibels (VdB). The vibration velocity level threshold of perception for humans is approximately 65 VdB. A vibration velocity level of 75 VdB is the approximate dividing line between barely perceptible and distinctly perceptible levels for many people. Most perceptible indoor vibration is caused by sources within buildings, such as operation of mechanical equipment, movement of people, or the slamming of doors. Typical outdoor sources of perceptible groundborne vibration are construction equipment, steel-wheeled trains, and traffic on rough roads. If a roadway is smooth, the groundborne vibration from traffic is rarely perceptible. The range of interest in groundborne vibration is from approximately 50 VdB, which is the typical background vibration velocity level, to 100 VdB, which is the general threshold where minor damage can occur in fragile buildings. Additionally, the FTA has established criteria for vibration sensitive research equipment, such as high- powered optical microscopes (1000X) and electron microscopes. Table 4.4-2 (Vibration Criteria for Specialized Research Equipment) details the FTA?s significance criteria for specialized equipment. Table 4.4-2 Vibration Criteria for Specialized Research Equipment Max VdB Description of equipment use 90 Distinctly feelable vibration. Appropriate to workshops and non-sensitive areas. 84 Feelable vibration. Appropriate to offices and non-sensitive areas. 78 Barely feelable vibration. Adequate for computer equipment and low-power optical microscopes (up to 20X). Vibration not feelable, but ground-borne noise may be audible inside quiet rooms. Suitable for medium-power optical 72 microscopes (100X) and other equipment of low sensitivity. Adequate for medium- to high-power optical microscopes (400X), microbalances, optical balances, and similar specialized 66 equipment. 66 Adequate for high-power optical microscopes (1000X), inspection and lithography equipment to 3 micron line widths 54 Appropriate for most lithography and inspection equipment to 1 micron detail size. Suitable in most instances for the most demanding equipment, including electron microscopes operating to the limits of their 48 capability. 42 The most demanding criterion for extremely vibration-sensitive equipment. SOURCE: HMMH 2006 The general human response to different levels of groundborne vibration velocity levels is described in Table 4.4 3 (Human Response to Different Levels of Groundborne Vibration). 4.4-4 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration Table 4.4-3 Human Response to Different Levels of Groundborne Vibration Vibration Velocity Level Human Reaction 65 VdB Approximate threshold of perception for many people. Approximate dividing line between barely perceptible and distinctly perceptible. Many people find that 75 VdB transportation-related vibration at this level is unacceptable. 85 VdB Vibration acceptable only if there are an infrequent number of events per day. SOURCE: HMMH 2006 Existing Noise Levels The existing Genentech Campus is bounded by San Francisco Bay on the north and the east, and connected by Oyster Point/Forbes Boulevard and Grand Avenue to US 101. It is bordered by rail lines on the west and northwest, connected to the Caltrain station to the west of the Genentech Campus, and is roughly one mile north of the San Francisco International Airport (SFIA). The Genentech Campus is built on and around San Bruno Hill, the highest point in the East of 101 Area. The General Plan currently designates two land use categories within the MEIR Study Area: 1) Business and Technology Park and 2) Park and Recreation. The majority of the MEIR Study Area is designated as Business Technology Park, with a narrow strip of land in the southern Genentech Campus that extends south along the coastline is designated as Park and Recreation. Existing uses within the East of 101 Area generally consist of warehouse, industrial and research and development activities. Under the City?s existing zoning regulations, the MEIR Study Area is contained within SSFMC Chapter 20.40: Genentech R&D Overlay District and within SSFMC Chapter 20.32: Planned Industrial District. The Genentech R&D Overlay District was adopted by the City in 1995 and currently extends over approximately 124 acres of Genentech property. The remainder of the EIR Study Area is not within the Genentech R&D Overlay District; rather the remainder of the area is within the underlying Planned Industrial zoning district. The entire East of 101 Area lies within the FAA height limit jurisdiction for the San Francisco International Airport. Along the Genentech Campus shoreline, the Bay Trail public right of way extends within the Bay Conservation and Development Commission (BCDC) jurisdiction, connecting the existing Genentech Campus to the San Francisco Bay regional park system. According to the South San Francisco General Plan, the primary noise sources within the City are streets and highways, rail operation, and industrial uses. As noted in Table 4.4-1, a jet fly-over at 100 feet produces noise levels of approximately 105 dBA; however, it is unlikely that jets fly-over the MEIR Study Area at such low altitudes. Within the MEIR Study Area, noise is primarily generated by airplane fly- overs from the nearby SFIA approximately one mile to the north. These potentially high single-event noise levels result from overflight of aircraft departing on the Shoreline Departure Route from runway 28 at SFIA. Background noise includes vehicle noise from US 101 approximately ½ mile to the southwest. Noise sources also include local sources such as vehicles in the parking areas, local vehicular traffic, municipal bus, and commercial truck traffic in and around the MEIR Study Area. Existing daytime noise levels were monitored at six locations in and around the MEIR Study Area in order to identify representative noise levels at various areas. The monitoring locations are identified in 4.4-5 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Figure 4.4-1 (Noise Monitoring Locations). The noise levels were measured using a Larson-Davis Model 720 precision sound level meter, which satisfies the American National Standards Institute (ANSI) for general environmental noise measurement instrumentation. The average noise levels and sources of noise measured at each location are identified in Table 4.4-4 (Existing Daytime Noise Levels at Selected Locations). These daytime noise levels are characteristic of a typical developed area. As shown, an ambient noise measurement taken at the site by EIP Associates on March 1, 2006 showed an existing noise level of 71.1 dBA L. The noise measurement taken at the Larkspur Landing Hotel, which is the eq nearest existing sensitive receptor to the MEIR Study Area, shows an ambient noise measurement of . 71.3 dBA L eq Table 4.4-4 Existing Daytime Noise Levels at Selected Locations Noise Level Statistics Noise Measurement Location Primary Noise Sources LLL eqminmax 1. Hotel parking lot—North of East Grand Avenue between Forbes Boulevard and Traffic on East Grand 67.7 59.8 77.9 Gateway Boulevard Avenue 2. Adjacent to Hotel parking lot—East of Gateway Boulevard between Corporate Traffic on Gateway 66.8 59.4 85.0 Drive and East Grand Avenue Boulevard 3. 500 Forbes Boulevard—South of Forbes Boulevard between Allerton Avenue Traffic on Forbes 70.6 55.7 90.9 and Gull Drive Boulevard 4. Adjacent to Genentech parking lot—Northeast of Forbes Boulevard and DNA Traffic on Forbes 71.1 52.3 89.2 Way intersection Boulevard 5. Adjacent to Hotel parking lot—Northeast of Airport Boulevard and Gateway Traffic on Gateway 71.3 65.9 89.2 Boulevard intersection Boulevard SOURCE: EIP Associates 2006. Noise levels were monitored for 10 minutes at each location on March 1, 2006. L, the minimum instantaneous noise level experienced during the measurement period. min L, the maximum instantaneous noise level experienced during the measurement period. max Sensitive Noise Receptors Sensitive receptors and noise sensitive uses are typically defined as residences, schools, places of worship, hospitals, care centers, and hotels that are sensitive to noise or locations where people might sleep. The nearest existing sensitive receptor to the MEIR Study Area is the Larkspur Landing Hotel, which is located approximately 2000 feet from the northwest boundary of the MEIR Study Area. Additionally, a childcare facility is proposed to be developed on Allerton Avenue as part of the proposed project. All other sensitive receptors are located further away and would not have the potential to be impacted by noise or vibration resulting from implementation of the proposed project. Existing Roadway Noise Levels Existing roadway noise levels were calculated for the roadway segments in the MEIR Study Area vicinity that have noise-sensitive uses facing the roadways. Roadway noise levels were calculated using the Federal Highway Administration Highway Noise Prediction Model (FHWA-RD-77-108) (FHWA Model) and traffic volumes from the project traffic study. The model calculates the average noise level at specific locations based on traffic volumes, average speeds, roadway geometry, and site environmental 4.4-6 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration conditions. The average vehicle noise rates (energy rates) utilized in the Federal Highway Administration Noise Prediction Model (FHWA Model) have been modified to reflect average vehicle noise rates identified for California by Caltrans. The Caltrans data show that California automobile noise is 0.8 to 1.0 dBA higher than national levels and that medium and heavy truck noise is 0.3 to 3.0 dBA lower than national levels. The average daily noise levels along these roadway segments are presented in Table 4.4-5 (Existing Roadway Noise Levels). Table 4.4-5 Existing Roadway Noise Levels off Site DistancetoNoiseContour b Reference CNEL at 100 Feet Roadway Segment a 70 CNEL 65 CNEL 60 CNEL Airport Blvd./Oyster Point Blvd. to Oyster Point west 63.3 — 68 214 b Airport Blvd./Oyster Point Blvd. to US 101 Ramps/Oyster Point Blvd. 63.7 — 75 237 US 101 Ramps/Oyster Point Blvd. to Oyster Point Blvd./Gateway Blvd. 66.0 — 127 402 Oyster Point Blvd./Gateway Blvd. to Oyster Point Blvd./Gull Rd. 64.2 — 82 260 Oyster Point Blvd./Gull Rd. to Oyster Point east 60.3 — — 106 Forbes Blvd./Gull Rd. to Forbes Blvd./Allerton Ave. 58.8 — — 76 Forbes Blvd./Gull Rd. to Forbes east 61.2 — — 131 Forbes Blvd./Allerton Ave. to Forbes Blvd. west 58.3 — — 68 Grandview Dr./E. Grand Ave. to E. Grand Ave. east 55.1 — — — Grandview Dr./E. Grand Ave. to Allerton Ave./Grand Ave. 61.7 — — 148 Forbes Ave./Grand Ave. to Gateway Blvd./E. Grand Ave. 64.4 — 86 273 Allerton Ave./Grand Ave. to Forbes Blvd./E. Grand Ave. 62.4 — — 174 Gateway Blvd./E. Grand Ave. to Executive/Grand Ave. 63.8 — 77 243 Executive/Grand Ave. to Dubuque Ave./Grand Ave. 63.8 — 75 238 Dubuque Ave./Grand Ave. to Airport Blvd./Grand Ave. 63.7 — 74 234 Airport Blvd./Grand Ave. to Grand Ave. west 60.6 — — 114 Airport Blvd./San Mateo to San Mateo west 60.7 — — 116 Gateway Blvd./Mitchell to Mitchell east 57.7 — — 59 Airport Blvd./Oyster Point Blvd. to Airport Blvd. north 62.0 — — 158 Airport Blvd./Oyster Point Blvd. to Airport Blvd./Miller 61.4 — — 138 Airport Blvd./Miller to Airport Blvd./Grand Ave. 63.2 — 67 211 Airport Blvd./Grand Ave. to Airport Blvd./San Mateo 64.1 — 82 260 Airport Blvd./San Mateo to Airport Blvd. south 64.3 — 86 271 Gateway Blvd./Mitchell to Gateway Blvd./E. Grand Ave. 61.8 — — 152 Gateway Blvd./E. Grand Ave. to Gateway Blvd./Oyster Point Blvd. 62.3 — — 170 Allerton Ave./Grand Ave. to Allerton Ave./Forbes Blvd. 53.6 — — — Grandview Dr./E. Grand Ave. to Grandview Dr. north 59.9 — — 99 Oyster Point Blvd./Gull Rd. to Forbes Blvd./Gull Rd. 60.4 — — 110 SOURCE: EIP Associates 2006. Calculation data and results are provided in Appendix D a Distances are in feet from roadway centerline. The identified noise level at 100 feet from the roadway centerline is for reference purposes only as a point from which to calculate the noise contour distances. It does not reflect an actual building location or potential impact location. b Noise contour is located within the roadway lanes. 4.4-9 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Existing Groundborne Vibration Levels The greatest regular sources of groundborne vibration at the MEIR Study Area and immediate vicinity are roadway truck and bus traffic. These sources typically generate noticeable groundborne vibration velocity levels at the edge of the road as they pass by. 4.4.2Regulatory Framework Federal There are no federal noise regulations applicable to the proposed project. State The California Government Code requires that a noise element be included in the General Plan of each county and city. Local The California Government Code requires that a noise element be included in the General Plan of each county and city in the state. Each local government?s goals, objectives, and policies for noise control are established by the noise element of the General Plan and the passage of specific noise ordinances. In the South San Francisco General Plan, the MEIR Study Area is shown to be in the East of 101 Area Plan. City of South San Francisco General Plan Noise Element The Noise Element of the General Plan identifies sources of noise in the City and provides objectives and policies that ensure that noise from various sources would not create an unacceptable noise environment. It is a tool that city planners use to achieve and maintain land uses with compatible environmental noise levels. Table 4.4-6 (Land Use Criteria for Noise Impacted Areas) shows the exterior noise standards as shown in the Noise Element of the General Plan. Consistency with the goals, policies, and strategies of the Noise Element of the General Plan is analyzed in Section 4.8 (Land Use). East of 101 Area Plan The East of 101 Area Plan Noise Element establishes policies to provide acceptable noise levels for anticipated land uses. These policies have been used to set criteria for the control of noise generated by individual aircraft flyover noise and for average noise levels. The purpose of these criteria is to reduce the various potential effects of noise on people, including sleep disturbance, reduced physical and mental performance, annoyance, and interference with speech communication. The East of 101 Area Plan identifies the MEIR Study Area as commercial development. According to the East of 101 Area Plan Noise Element, the requirements for commercial land uses such as industrial, office, and retail indicate that the interior calculated hourly noise levels during the daytime should not exceed 45 dBA L and eq instantaneous maximum noise levels should not exceed 60 dBA. The Noise Element also establishes a 4.4-10 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration policy to ensure that new development be designed so that the average noise level does not exceed a L eq of 60 dBA at the nearest open space or recreational area. Table 4.4-6 Land Use Criteria for Noise Impacted Areas Land Use dBA CNEL Range General Land Use Criteria Less than Satisfactory; no special insulation requirements 65 dBA CNEL Residential 65 to 70 Development requires analysis of noise reduction requirements and noise insulation as needed Over 70 Development should not be undertaken Less than 70 Satisfactory; no special insulation requirements Commercial 70 to 80 Development requires analysis of noise reduction requirements and noise insulation as needed Over 80 Airport-related development only; special noise insulation should be provided Less than 75 Satisfactory; no special insulation requirements Industrial 75 to 85 Development requires analysis of noise reduction requirements and noise insulation as needed Over 85 Airport-related development only; special noise insulation should be provided Less than 75 Satisfactory; no special insulation requirements Open Over 75 Avoid uses involving concentrations of people or animals SOURCE: City of South San Francisco General Plan Noise Element (1999). Consistency with the goals, policies, and strategies of the Noise Element of the East of 101 Area Plan is analyzed in Section 4.8 (Land Use). City of South San Francisco Municipal Code The City of South San Francisco has adopted a Noise Ordinance (Chapter 8-32 of the SSFMC), which identifies ambient baseline noise levels, noise standards for various sources, specific noise restrictions, exemptions, and variances for sources of noise within the City. The noise levels are used as baseline criteria for noise levels for different land use categories. The SSFMC Section 8.32.030 provides noise level standard for specific zones and land uses within the City (see Table 4.4-7). The noise standards apply to all noise sources with the exception of vehicle horns and utility and emergency vehicles. Table 4.4-7 City of South San Francisco Noise Level Standard Land Use Category Time Period Noise Level (dB) 10..–7.. 50 PMAM R-E, R-1 and R-2 zones or any single-family or duplex residential in a specific plan district ..–10.. 60 7 AMPM 10..–7.. 55 R-3 and D-C zones or any multiple-family residential or mixed residential/commercial in any PMAM specific plan district 7..–10.. 65 AMPM 10..–7.. 60 C-1, P-C, Gateway and Oyster Point Marina specific plan districts or any commercial use in PMAM any specific plan district 7..–10.. 65 AMPM M-1, P-1 Anytime 70 SOURCE: City of South San Francisco Municipal Code Section 8.32.030 4.4-11 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Per Section 8.32.050(d) of the SSFMC, construction activities are exempt from the noise level standards .. to 8:00 .. on weekdays, 9:00 .. to 8:00 .. on listed in Table 4.4-7 during the hours of 8:00 AMPMAMPM Saturdays, and 10:00 .. to 6:00 .. on Sundays and holidays. The exemption is only allowed if the AMPM construction equipment does not produce a noise level greater than 90 dBA at 25 feet from the source or 90 dBA outside of the property line, whichever is greater. 4.4.3Impacts and Mitigation Measures Analytic Method Implementation of the proposed project could result in the introduction of noise levels that may exceed permitted City noise levels. The primary sources of noise associated with the proposed project would be construction activities within the MEIR Study Area and project-related traffic volumes associated with operation of the proposed project. Secondary sources of noise would include new stationary sources (such as heating, ventilation, and air conditioning units) and increased human activity throughout the MEIR Study Area. The net increase in noise levels generated by these activities and other sources have been quantitatively estimated and compared to the applicable noise standards and thresholds of significance. Aside from noise levels, groundborne vibration would also be generated during the construction phase of the proposed project by various construction equipment. Thus, the groundborne vibration levels generated by construction equipment have also been quantitatively estimated and compared to applicable thresholds of significance. Construction Noise Levels Construction noise levels were estimated by data published by the U.S. Environmental Protection Agency (EPA). Potential noise levels are identified for on- and off-site locations that are sensitive to noise, including hotels and sensitive research facilities. The EPA has compiled data regarding the noise-generating characteristics of typical construction activities. These noise levels would diminish rapidly with distance from the construction site, at a rate of approximately 6 dBA per doubling of distance. For example, a noise level of 86 dBA measured at 50 feet from the noise source to the receptor would reduce to 80 dBA at 100 feet from the source to the receptor, and reduce by another 6 dBA to 74 dBA at 200 feet from the source to the receptor. Roadway Noise Levels Roadway noise levels have been calculated for various locations around the MEIR Study Area. The noise levels were calculated using the FHWA-RD-77-108 model and traffic volumes from the project traffic study. The average vehicle noise rates (energy rates) utilized in the FHWA Model have been modified to reflect average vehicle noise rates identified for California by Caltrans. Traffic volumes used in the FHWA model are derived from the project traffic study, which is provided in Appendix E and summarized in Section 4.7 (Transportation/Traffic) of this document. 4.4-12 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration VibrationLevelsAssociatedwithConstructionEquipment Groundborne vibration levels resulting from construction activities occurring within the MEIR Study Area were estimated by data published by Harris Miller Miller & Hanson Inc. for the Federal Transit Administration. Potential vibration levels are identified for on- and off-site locations that are sensitive to vibration, including hotels and sensitive research facilities. Thresholds of Significance The following thresholds of significance are based on Appendix G of the 2006 CEQA Guidelines. For purposes of this MEIR, implementation of the proposed project could result in potentially significant impacts from noise and vibration if the proposed project would result in any of the following: 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 Cause substantial permanent increase in ambient noise levels in the proposed project vicinity above levels existing without the proposed project Cause a substantial temporary or periodic increase in ambient noise levels in the proposed project vicinity above levels existing without the proposed project Expose people residing or working in the project site to excessive noise levels from 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 site to excessive noise levels from a project located within the vicinity of a private airstrip The CEQA Guidelines do not define the levels at which temporary and permanent increases in ambient noise are considered ?substantial.? As discussed previously in this section, a noise level increase of 3 dBA is barely perceptible to most people, a 5 dBA increase is readily noticeable, and a difference of 10 dBA would be perceived as a doubling of loudness. Based on this information, a 3 dBA CNEL increase would be considered significant. The CEQA Guidelines also do not define the levels at which groundborne vibration or groundborne noise is considered ?excessive.? For the purpose of this analysis, groundborne vibration impacts associated with human annoyance would be significant if the proposed project exceeds 85 VdB, which is the vibration level that is considered by the Federal Transit Administration (FTA) to be acceptable only if there are an infrequent number of events per day (as described in Table 4.4-2 [Human Response to Different Levels of Groundborne Vibration]). Groundborne vibration impacts associated with the use of vibration sensitive equipment would be significant if the proposed project exceeds 66 VdB, as described in Table 4.4-3. 4.4-13 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Impacts and Mitigation Threshold Expose persons to or generate noise levels in excess of standards established in the local general plan or noise ordinances, or applicable standards of other agencies Impact 4.4-1 Construction activities associated with the proposed project would generate noise levels that exceed the noise standards established by the SSFMC. This is considered a potentially significant impact. Compliance with the project requirement PR 4.4-1 and mitigation measures MM 4.4-1(a) through MM 4.4-1(c) would reduce this impact, but noise levels could still be substantial. However, the proposed project?s construction noise impacts would be temporary, would not occur during recognized sleep hours, and would be consistent with the exemption for construction noise that exists in Section 8.32.050(d) of the SSFMC. less than significant Therefore, this impact would be considered . Implementation of the proposed project could result in the development of approximately 3.17 million sf of office, research and development, manufacturing, amenities, and parking by the year 2016. The proposed project would also include vehicular access and roadway improvements, as well as associated utility infrastructure improvements and physical amenities, such as landscape, hardscape, and lighting. Construction activities occurring within the MEIR Study Area would involve excavation and grading activities followed by construction of the proposed facilities and associated parking as well as roadway and landscaping improvements, which would involve the use of heavy equipment. Construction activities would also involve the use of smaller power tools, generators, and other equipment that are sources of noise. Haul trucks using the local roadways would generate noise as they move along the road. Each stage of construction would involve a different mix of operating equipment, and noise levels would vary based on the amount and types of equipment in operation and the location of the activity. Sensitive uses that would be affected (depending on the distance from the project site) by the construction noise occurring as a result of the proposed project include the Larkspur Landing Hotel, which is located approximately 2000 feet from the northwest boundary of the MEIR Study Area, and the proposed childcare center to be located on Allerton Avenue. Based on the information presented in Table 4.4-8 (Typical Outdoor Construction Noise Levels) and the diminishment of noise levels at a rate of 6 dBA per doubling of distance, the maximum noise levels experienced by the Larkspur Landing Hotel due to construction activities occurring at the MEIR Study Area and off site would be 54 dBA. As the childcare center is to be constructed as part of the proposed project, construction noise would not affect the childcare center until it is operational. The 2006 FMPU spans a 10 year planning horizon, during which the childcare center could be in operation during future construction on the Genentech Campus; however, no construction activities are planned to be within 200 feet of the proposed childcare center. Therefore, the construction activity noise levels that the childcare center would potentially be exposed to would be no more then 74 dBA. 4.4-14 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration Table 4.4-8 Typical Outdoor Construction Noise Levels Noise Level at 50 Noise Level at 60 Noise Level at 100 Noise Level at 200 Noise Level at 2,000 FeetwithMufflersFeetwithMufflersFeetwithMufflersFeetwithMufflersFeetwithMufflers (dBA L)(dBA L)(dBA L)(dBA L)(dBA L) Construction Phase eqeqeqeqeq Ground Clearing 82 80 76 70 50 Excavation/Grading 86 84 80 74 54 Foundations 77 75 71 65 45 Structural 83 81 77 71 51 External Finishing 86 84 80 74 54 SOURCES: U.S. EPA 1971 As discussed above and shown in Table 4.4-8 (Typical Outdoor Construction Noise Levels), the proposed childcare center located on Allerton Avenue could potentially be exposed during the daytime to construction noise levels that exceed the City?s exterior noise standard of 60 dBA CNEL if construction staging occurs adjacent to the operational childcare center. Although the construction activities would exceed the 60 dBA CNEL noise standard identified in the SSFMC at these locations during construction at the MEIR Study Area, the increase in noise levels would be temporary in nature, and would not generate continuously high noise levels, although occasional single-event disturbances from grading and construction are possible. Further, although the construction noise levels for the proposed project are provided in CNEL, which is a 24-hour average L with noise penalties added eq during specific hours of the day to account for noise sensitivity in the evening and nighttime, these noise levels associated with the proposed project would only be generated during 12 hours of the day .. to 8:00 .. for weekdays) and not for 24 continuous hours. However, because the maximum (8:00 AMPM City?s exterior noise standards are given in CNEL, the construction noise levels associated with the proposed project have been converted from L to CNEL for the purpose of analysis in this MEIR. eq Currently, under Section 8.32.050(d) of the SSFMC, construction activities are limited to between the .. to 8:00 .. on weekdays, 9:00 .. to 8:00 .. on Saturdays, and 10:00 .. to hours of 8:00 AMPMAMPMAM 6:00.. on Sundays and holidays, as discussed in Section 4.4.2 of this section. As such, the following PM project requirement shall be incorporated, as required by applicable local, state, or federal laws or regulations: PR 4.4-1 All construction activity within the City shall be limited to between the hours of 8:00 .. to AM 8:00.. on weekdays, 9:00 .. to 8:00 .. on Saturdays, and 10:00 .. to 6:00 .. PMAMPMAMPM on Sundays and holidays. Construction noise that occurs during these hours is exempt from the City?s Noise Ordinance because these hours are outside of the recognized sleep hours for residents and outside of evening and early morning hours and time periods where residents are most sensitive to exterior noise. Consequently, the City considers impacts resulting from construction noise during these hours to be less than significant. The nearest noise sensitive uses near the MEIR Study Area are the Larkspur Landing Hotel, and the proposed childcare center once it is operational. Occupants of these sensitive uses are likely to be present throughout the day and consequently would be more sensitive to higher noise levels generated during 4.4-15 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis daytime hours. Although the City?s exemption would apply to project construction noise heard at these noise sensitive uses, their sensitive nature means that noise should be reduced where feasible: To reduce the noise levels resulting from construction of the proposed project to the extent feasible, the following mitigation measures shall be implemented: MM 4.4-1(a) The project applicant shall require by contract specifications that the following construction best management practices (BMPs) be implemented by contractors to reduce construction noise levels: Two weeks prior to the commencement of construction, notification must be provided to surrounding land uses disclosing the construction schedule, including the various types of activities that would be occurring throughout the duration of the construction period Ensure that construction equipment is properly muffled according to industry standards Place noise-generating construction equipment and locate construction staging areas away from sensitive uses, where feasible Schedule high noise-producing activities between the hours of 8:00 .. and 5:00 .. to AMPM minimize disruption on sensitive uses Implement noise attenuation measures to the extent feasible, which may include, but are not limited to, noise barriers or noise blankets MM 4.4-1(b) The project applicant shall require by contract specifications that construction staging areas along with the operation of earthmoving equipment within the MEIR Study Area would be located as far away from vibration and noise sensitive sites as possible. Contract specifications shall be included in the construction documents, which shall be reviewed by the City prior to issuance of a grading permit. MM 4.4-1(c) The project applicant shall require by contract specifications that heavily loaded trucks used during construction would be routed away from noise- and vibration-sensitive uses, to the extent possible. Contract specifications shall be included in the construction documents, which shall be reviewed by the City prior to issuance of a grading permit. Under mitigation measure MM 4.4-1(a), the implementation of noise attenuation measures may include the use of noise barriers (e.g., sound walls) or noise blankets. As a general rule of thumb, a sound wall is able to reduce noise by 5 dBA. In addition, mitigation measure MM 4.4-1(b), which requires that construction staging areas and earthmoving equipment be located as far away from vibration-sensitive land uses as possible, and mitigation measure MM 4.4-1(c), which requires that heavily loaded trucks be routed away from residential uses to the extent possible, would also reduce construction-related noise levels. No other feasible mitigation measures are available. Since construction noise would be reduced where feasible, and because construction noise is exempted by the provisions of the SSFMC, this impact less-than-significant would be . 4.4-16 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration Impact 4.4-2 Operation of the proposed project would not expose noise-sensitive land uses off site to noise levels that exceed the standards established by the less than significant City of South San Francisco. This impact would be . Large HVAC systems associated with new buildings in the MEIR Study Area can result in noise levels that average between 50 and 65 dBA L at 50 feet from the equipment. As discussed previously in this eq measurements. This section, 24-hour CNEL noise levels are about 6.7 dBA greater than 24-hour L eq means that the HVAC equipment installed under the proposed project could generate noise levels that average between 57 to 72 dBA CNEL at 50 feet when the equipment is operating constantly over 24 hours. These HVAC units would be mounted on the rooftops of the proposed buildings and would be screened from view by building features. When the proposed childcare center to be located on Allerton Avenue is operational, occupants of the childcare center could potentially be exposed to noise levels as high as 72 dBA CNEL as a result of the operation of these HVAC units. Noise levels may also be reduced by intervening structures; generally, a single row of buildings between the receptor and the noise source reduces the noise level by about 5 dBA, while a solid wall or berm reduces noise levels by 5 to 10 dBA. The manner in which older commercial structures in California were constructed (approximately 30 years old or older) generally provides a reduction of exterior-to-interior noise levels of about 20 to 25 dBA with closed windows. The exterior-to-interior reduction of newer commercial is generally 30 dBA or more (HMMH 2006). However, it is expected that the childcare center would only be in operation during typical business days and would not be occupied during evening and nighttime hours. As such, occupants of the proposed childcare center would not be exposed to noise levels above the City?s 75 dBA CNEL limit established for industrial land uses, which is the land use designation for the MEIR Study Area; therefore, this less than significant impact would be considered . The nearest off-site sensitive receptors to the MEIR Study Area is the Larkspur Landing Hotel. The Larkspur Landing Hotel is located approximately 2000 feet from the northwest boundary of the MEIR Study Area. As discussed in Impact 4.4-1, noise levels would diminish rapidly with distance from the MEIR Study Area at a rate of approximately 6 dBA per doubling of distance. Thus, the noise levels generated by the HVAC equipment associated with the new buildings would be approximately 42 dBA CNEL at the Larkspur Landing Hotel. Since the noise levels that would be experienced by the sensitive receptor nearest to the MEIR Study Area would be below the 50 dBA CNEL standard for night-time less than significant use, this impact would be . No mitigation is required. Impact 4.4-3 Operation of the proposed project would not generate traffic that would contribute to the exposure of persons off site to noise levels in excess of the less-than-significant standards. This is considered a impact. As discussed in detail in Impact 4.4-6, traffic-related noise would increase by as much as 4.1 dBA CNEL at project buildout in the Year 2016, which is in excess of the 3.0 dBA CNEL threshold of significance for traffic-related noise. However, as shown in Table 4.9-10, traffic noise levels would not exceed the 75 dBA CNEL noise limit for industrial and institutional uses. As the proposed project would not exceed less than significant local noise standards for the City of South San Francisco, this impact would be . 4.4-17 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Threshold Expose persons to or generate excessive groundborne vibration or groundborne noise levels Impact 4.4-4 Construction activities associated with the proposed project would not generate or expose persons or structures off site to excessive groundborne vibration. However, the construction activities may adversely affect vibration sensitive equipment within the MEIR Study Area. Implementation of mitigation measures MM 4.4-2(a) and MM 4.4-2(b) . would reduce this impact to a less?than-significant level Construction activities that would occur under the proposed project both within the MEIR Study Area and off site would include excavation, which would have the potential to generate low levels of groundborne vibration. Table 4.4-9 (Vibration Source Levels for Construction Equipment) identifies various vibration velocity levels for the types of construction equipment that would operate within the MEIR Study Area during construction. Based on the information presented in Table 4.4-8, vibration levels could reach as high as approximately 87 VdB within 25 feet of the MEIR Study Area. Construction activities occurring under the proposed project would have the potential to impact the nearest sensitive receptors to the MEIR Study Area in areas where construction staging would occur closer to these receptors, including the Larkspur Landing Hotel and during operation of the proposed childcare center. Table 4.4-9 Vibration Source Levels for Construction Equipment Construction Equipment Approximate VdB at 25 feet Large Bulldozer 87 Caisson Drilling 87 Loaded Trucks 86 Jackhammer 79 Small Bulldozer 58 SOURCE: HMMH 1995 Given the distance of the Larkspur Landing Hotel, from the MEIR Study Area, the vibration levels experienced at the property could reach up to approximately 51 VdB. Further, no construction activity is proposed within 200 feet of the proposed childcare center during its operation. Even if construction were to occur closer to these sensitive receptors, the construction would have to be within approximately 25 feet of the use to exceed the 85 VdB threshold. As no off-site sensitive uses are calculated to be within 25 feet of construction activity at any location, groundborne vibration would not exceed the less FTA?s vibration impact threshold of 85 VdB for human annoyance, therefore, this impact would be than significant . No mitigation is required. Although trenching would also occur within the MEIR Study Area for the installation of utility lines, the construction equipment that is expected to be used for this activity would be either small backhoes or trenchers. The groundborne vibration levels generated from either of these pieces of equipment would not be greater than the vibration levels generated by a large bulldozer. Consequently, the groundborne vibration levels resulting from trenching activities within the MEIR Study Area would not exceed 4.4-18 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration 85 VdB thresholds for human annoyance. Therefore, the vibration impacts resulting from trenching less than significant activities associated with the proposed project would be . No mitigation is required. Heavy trucks would be used to transport materials to and from the MEIR Study Area when construction activities occur. The construction haul route would include use of Forbes Boulevard, Grand Avenue, and Gateway Boulevard and US 101 Freeway. These trucks typically generate groundborne vibration velocity levels of around 63 VdB. These levels could reach 72 VdB where trucks pass over bumps in the road. The groundborne vibration velocity levels generated by these trucks would be less than the FTA?s 85 VdB vibration impact threshold for human annoyance. Thus, impacts related to groundborne less than significant vibration from heavy trucks would be . No mitigation is required. However, implementation of mitigation measure MM 4.4-1(c) would ensure that the vibration levels caused by the operation of heavy trucks would be further minimized to the extent feasible at the sensitive land uses in the vicinity of the MEIR Study Area by requiring routing of loaded trucks away from sensitive uses to the extent possible. Genentech potentially use research equipment that may be especially vibration sensitive. The threshold for vibration sensitive equipment is 66 VdB (HMMH 2006). Construction activities have the potential to occur within 25 feet of buildings containing vibration sensitive equipment. This would potentially expose the equipment to vibration levels up to 87 VdB, which exceeds the 66 VdB threshold; therefore, this impact is potentially significant. In order to reduce this impact, mitigation measures MM 4.4-2(a) and MM 4.4-2(b) shall be implemented. MM 4.4-2(a) Prior to the commencement of ground clearing activities, the project applicant shall conduct a pre- construction survey to determine whether the construction project?s activities would impact vibration sensitive equipment located in adjacent buildings within 100 feet of the construction activity. If it is determined that no impact would occur then construction activities shall begin and no further action need be taken. MM 4.4-2(b) If the project applicant determines that vibration sensitive equipment has the potential to be affected, it shall implement a construction schedule to ensure that construction activities would occur during times when vibration sensitive equipment would not be in use. Implementation of mitigation measure MM 4.4-2(a) would ensure that construction related activities, including caisson drilling would not occur adjacent to existing buildings containing vibration sensitive equipment. If construction activities were to occur adjacent to building containing vibration sensitive equipment, mitigation measure MM 4.4-2(b) would ensure that construction activities that could potentially impact vibration sensitive equipment, such as pile-driving, would be scheduled such that vibration sensitive equipment would not be impacted. With implementation of mitigation measures MM 4.4-2(a) and MM 4.4-2(b), the potentially significant impact to vibration sensitive equipment would less than significant. be reduced to a level of No further mitigation is required. 4.4-19 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Impact 4.4-5 Operation of the proposed project would not generate and expose sensitive receptors on or off site to excessive groundborne vibration or groundborne less-than-significant noise levels. This is considered a impact. During operation of the proposed project, background operational vibration levels would be expected to average around 50 VdB, as discussed previously in this section. This is substantially less than the 85 VdB threshold for people in the vicinity of the project site. Groundborne vibration resulting from operation of the proposed project would primarily be generated by trucks making periodic deliveries to the MEIR Study Area. However, these types of deliveries would be consistent with deliveries that are currently made along roadways in the project vicinity to the existing Genentech Campus and would not increase groundborne vibration above existing levels. Because no substantial sources of groundborne vibration would be built as part of the proposed project, no vibration impacts would occur during operation of the proposed project. Therefore, operation of the proposed project would not expose sensitive receptors on less or off site to excessive groundborne vibration or groundborne noise levels, and this impact would be than significant . No mitigation is required. Threshold Cause substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the proposed project Impact 4.4-6 Operation of the proposed project would generate increased local traffic volumes that would cause a substantial permanent increase in ambient noise levels in the project vicinity. This is considered a significant impact. As no feasible mitigation is available to reduce this impact, this impact significant and unavoidable would be . Future noise levels within the City would continue to be dominated by vehicular traffic on the adjacent roadways. Other sources of noise would include new stationary sources (such as rooftop heating, ventilation, and air conditioning equipment) and increased human activity throughout the City. Locations in the project vicinity could experience slight changes in noise levels as a result of an increase in the on-site uses due to the potential development under the proposed project and resulting increase in motor vehicle trips. Existing traffic noise levels are identified in Table 4.4-5. Noise levels associated with traffic generated from Year 2015 proposed project buildout, are calculated at the selected locations along the study-area roadway segments within the City of South San Francisco using traffic data from the project Traffic Study (Section 4.7 (Transportation) and Appendix E of this MEIR). As stated in the Thresholds of Significance above, a 3.0 dBA CNEL increase is considered substantial. Table 4.4-10 (Traffic Noise Impacts for Proposed Project Buildout in Year 2015) presents the future average daily noise levels associated with these roadways under Year 2015 buildout and compares them to existing conditions. 4.4-20 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration Table 4.4-10 Traffic Noise Impacts for Proposed Project Buildout in Year 2015 Noise Levels in dBA CNEL at 100 feet ExistingYear 2015 Significance Exceeds Significance Roadway Segment Conditions With Project Increase ThresholdThreshold? 1 Airport Blvd./Oyster Point Blvd. to Oyster 63.3 64.6 1.3 3.0 No Point west Airport Blvd./Oyster Point Blvd. to US 63.7 65.2 1.5 3.0 No 101 Ramps/Oyster Point Blvd. US 101 Ramps/Oyster Point Blvd. to 66.0 67.9 1.9 3.0 No Oyster Point Blvd./Gateway Blvd. Oyster Point Blvd./Gateway Blvd. to 64.2 66.2 2.0 3.0 No Oyster Point Blvd./Gull Rd. Oyster Point Blvd./Gull Rd. to Oyster 60.3 60.6 0.3 3.0 No Point east Forbes Blvd./Gull Rd. to Forbes 58.8 61.9 3.13.0Yes Blvd./Allerton Ave. Forbes Blvd./Gull Rd. to Forbes east 61.2 61.5 0.3 3.0 No Forbes Blvd./Allerton Ave. to Forbes 58.3 59.6 1.3 3.0 No Blvd. west Grandview Dr./E. Grand Ave. to E. Grand 55.1 59.2 4.13.0Yes Ave. east Grandview Dr./E. Grand Ave. to Allerton 61.7 64.9 3.23.0Yes Ave./Grand Ave. Forbes Ave./Grand Ave. to Gateway 64.4 67.1 2.7 3.0 No Blvd./E. Grand Ave. Allerton Ave./Grand Ave. to Forbes 62.4 65.5 3.13.0Yes Blvd./E. Grand Ave. Gateway Blvd./E. Grand Ave. to 63.8 65.6 1.8 3.0 No Executive/Grand Ave. Executive/Grand Ave. to Dubuque 63.8 65.4 1.6 3.0 No Ave./Grand Ave. Dubuque Ave./Grand Ave. to Airport 63.7 65.5 1.8 3.0 No Blvd./Grand Ave. Airport Blvd./Grand Ave. to Grand Ave. 60.6 62.2 1.6 3.0 No west Airport Blvd./San Mateo to San Mateo 60.7 60.8 0.1 3.0 No west Gateway Blvd./Mitchell to Mitchell east 57.7 59.4 1.7 3.0 No Airport Blvd./Oyster Point Blvd. to Airport 62.0 64.1 2.1 3.0 No Blvd. north Airport Blvd./Oyster Point Blvd. to Airport 61.4 62.4 1.0 3.0 No Blvd./Miller Airport Blvd./Miller to Airport Blvd./Grand 63.2 64.1 0.9 3.0 No Ave. Airport Blvd./Grand Ave. to Airport 64.1 64.2 0.1 3.0 No Blvd./San Mateo Airport Blvd./San Mateo to Airport Blvd. 64.3 66.6 2.3 3.0 No south 4.4-21 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis Table 4.4-10 Traffic Noise Impacts for Proposed Project Buildout in Year 2015 Noise Levels in dBA CNEL at 100 feet ExistingYear 2015 Significance Exceeds Significance Roadway Segment Conditions With Project Increase ThresholdThreshold? 1 Gateway Blvd./Mitchell to Gateway 61.8 64.3 2.5 3.0 No Blvd./E. Grand Ave. Gateway Blvd./E. Grand Ave. to Gateway 62.3 63.1 0.8 3.0 No Blvd./Oyster Point Blvd. Allerton Ave./Grand Ave. to Allerton 53.6 55.8 2.2 3.0 No Ave./Forbes Blvd. Grandview Dr./E. Grand Ave. to 59.9 62.8 2.9 3.0 No Grandview Dr. north Oyster Point Blvd./Gull Rd. to Forbes 60.4 62.9 2.5 3.0 No Blvd./Gull Rd. SOURCE: EIP Associates 2006 (calculation data and results are provided in Appendix H) 1. As described in Section 4.4-3 (Thresholds of Significance), the significance threshold is 3 dBA if the noise increase would meet or exceed the City?s 65 dBA CNEL noise level standard at sensitive land uses. However, if the noise levels remain below the City?s 65 dBA CNEL noise level standard at sensitive land uses, then an increase in noise between 3 dBA and 5 dBA would be noticeable, but would not be considered to be significant. 2. Although a significant increase in ambient noise over existing conditions is experienced at this roadway segment, this roadway segment would not be located adjacent to any existing or proposed sensitive uses. As shown in Table 4.4-10, four roadway segments are expected to experience a significant increase over existing conditions, with a maximum increase of 4.1 dBA CNEL, which is considered an audible and substantial increase and would exceed the identified thresholds of significance. All other roadway segments in the project vicinity would not experience increase in traffic-related noise above the 3.0 dBA CNEL threshold of significance. However, it should be noted these roadway segments would not be located adjacent to any existing or proposed sensitive uses. Nonetheless, these roadway segments would experience an increase in traffic-related noise levels in excess 3.0 dBA CNEL, which is considered a significant impact. As no feasible mitigation is available to reduce this impact, this impact would be significant and unavoidable . Threshold Cause a substantial temporary or periodic increase in ambient noise levels in the project vicinity above levels existing without the proposed project Impact 4.4-7 Construction activities associated with the proposed project would result in a substantial temporary or periodic increase in ambient noise levels at off- site locations. However, construction noise is exempt from the City?s less than significant Noise Ordinance; thus, this impact would be . As discussed in Impact 4.4-1, construction activities associated with the proposed project during the daytime could result in noise levels as high as 54 dBA L at the Larkspur Landing Hotel, located eq northwest of the MEIR Study Area. As daytime noise monitored at the Larkspur Landing Hotel is , as shown in Table 4.4-3, these construction activities would not represent a substantial 71.3 dBA L eq temporary or periodic increase in ambient noise levels at the off-site sensitive use locations. As discussed under Thresholds of Significance, this MEIR assumes that an increase of 3 dBA or greater over ambient noise levels is significant. Ambient noise levels at off-site sensitive receptors would not increase by more than 3 dBA during construction of the proposed project. 4.4-22 Genentech Corporate Facilities Master EIR 4.4 Noise and Vibration The construction activities associated with the proposed project would only occur during the permitted hours designated in the SSFMC. In addition, as discussed in Impact 4.4-1, construction noise that occurs within the permitted time frames is exempt from the City?s Noise Ordinance. Due to this exemption, the temporary increases in ambient noise at off-site locations associated with construction activities of the less than significant proposed project would be . Impact 4.4-8 Operation of the proposed project would not result in temporary or periodic increases in ambient noise levels at off-site locations. There would no impact not be a substantial temporary or periodic increase and, thus, would occur. Operation of the proposed project would not include special events or temporary activities which would cause an increase in ambient noise levels. In addition, operation of the proposed project would not require periodic use of special stationary equipment that would expose off-site sensitive receptors to an increase in ambient noise levels above those existing without the proposed project. Therefore, there would be no temporary or periodic noise impacts to off-site receptors due to operation of the proposed No impact project. would occur. No mitigation would be required. Threshold Expose people residing or working in the project site to excessive noise levels from 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 Impact 4.4-9 The proposed project would not expose people working in the project area to excessive noise levels due to proximity to airport-related noise sources. No impact would occur. The MEIR Study Area is located approximately one mile from the San Francisco International Airport. Noise measurements taken on site showed the ambient levels at the site to be 71 dBA during daytime hours and contour levels from the East of 101 Area Plan indicate that the exposure level at the project site is less than 65 dBA CNEL. In addition, no residences currently, or are planned to, exist within the MEIR Study Area. Therefore, the proposed project would not expose people residing or working in the no impact project area to excessive noise levels, and would occur. No mitigation would be required. Threshold Expose people residing or working in the project site to excessive noise levels from a project located within the vicinity of a private airstrip. Impact 4.4-10 The proposed project would not expose people residing or working in the project site to excessive noise levels from a project located within the No impact vicinity of a private airstrip. would occur. The EIR Study Area is not located within the vicinity of a private airstrip. Thus, no impact related to the exposure of people residing or working in the MEIR Study Area to excessive noise levels is anticipated, and no further analysis is required in this MEIR. Therefore, the proposed project would not expose 4.4-23 Genentech Corporate Facilities Master EIR Chapter 4 Environmental Analysis no impact people residing or working in the project area to excessive noise levels, and would occur. No mitigation would be required. 4.4.4References Brady and Associates. 1994. East of 101 Area Plan, City of South San Francisco. July. Dyett and Bhatia. 2005. Genentech Central Campus Ten-Year Master Plan, Draft, November. Genentech. 2005. Genentech Existing Conditions Report. Prepared by Nelson/Nygaard Consulting Associates and Fehr & Peers Transportation Consultants, April. Harris Miller Miller & Hanson Inc. 1995. Transit Noise and Vibration Impact Assessment, Final Report, April. Harris Miller Miller & Hanson Inc. 2006. Transit Noise and Vibration Impact Assessment, Final Report, May. Hendriks, R. 1998. Technical Noise Supplement: A Technical Supplement to the Traffic Noise Analysis Protocol. California Department of Transportation (Caltrans), Sacramento, California. October. San Mateo County Airport Land Use Commission FAA Height and Noise Contours, 2000. South San Francisco, City of. 1999. City of South San Francisco General Plan Noise Element, October. ???.Municipal Code. Updated June 2005. United States Department of Transportation. Federal Highway Administration. 1980a. Highway Noise Fundamentals. ???. Federal Highway Administration. 1980b. Fundamentals and Abatement of Highway Traffic Noises. September. ???. Federal Highway Administration. 1980c. Highway Noise Mitigation. ???. Federal Highway Administration. n.d. Traffic Noise Prediction Model (FHWA-RD-77-108). ???. Federal Railroad Administration. 1998. High-Speed Ground Transportation Noise and Vibration Impact Assessment. United States Environmental Protection Agency. 1971. Noise from Construction Equipment and Operations, Building Equipment and Home Appliances. 4.4-24 Genentech Corporate Facilities Master EIR