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Appendix E_Noise Technical Memo DEIR 10 12 18.pdf
APPENDIX E Noise Technical Memo ACOUSTICS Acoustical & Audiovisual Consultants APPENDIX E: NOISE IMPACT ANALYSIS FOR: 201 HASKINS WAY SOUTH SAN FRANCISCO, CA RGD Project #: 18 -026 PREPARED FOR: SWCA Environmental Consultants 330 Townsend Street, Suite 216 San Francisco, CA 94107 PREPARED BY: Alan Rosen Harold Goldberg, P.E. Tsz "Anthony" Wong DATE: 10 October 2018 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Introduction Page 1 of 25 10 October 2018 This report analyzes the potential off -site noise impacts associated with the proposed project at 201 Haskins Way in South San Francisco. The project will be constructed in two phases. Phase 1 consists of the demolition of a one -story building located at 201 Haskins Way (Parcel 015 - 102 -230), the development of a three -story and a five -story office building along with a parking lot structure at the same parcel, and construction of an approximately 25,000 square foot addition to an existing office /R &D building located at 400 -450 East Jamie Court (APN 015 -102- 250). Currently there is no site - specific development program proposed for Phase 2. The proposed rezoning of the parcels in the Phase 2 area would allow the existing uses to continue indefinitely and would allow redevelopment at 1.0 FAR in accordance with the proposed Business Technology Park District rezoning. The environmental impact report prepared for the project evaluates the maximum potential development that could occur on those parcels under the proposed rezoning. While final square footage of the conceptual redevelopment of the Phase 2 area is unknown at this time, under the Preliminary Phase 2 Conceptual Development Plan, Phase 2 would include expansion of the Phase 1 parking lot structure, the demolition of five existing light industrial buildings along East Grand Avenue, and the development of a three- and five -story office building along East Grand Avenue. 2 Fundamental Concepts of Environmental Noise Terminology: Noise can be defined as unwanted sound and is commonly measured with an instrument called a sound level meter. The sound level meter "captures" sound with a microphone and converts it into a number called a sound level. Sound levels are expressed in units of decibels (dB). To correlate the microphone signal to a level that corresponds to the way humans perceive noise, the A- weighting filter is used. A- weighting de- emphasizes low- frequency and very high - frequency sound in a manner similar to human hearing. The use of A- weighting is required by most local agencies as well as other federal and State noise regulations (e.g. Caltrans, EPA, OSHA and HUD). The abbreviation dBA is often used when the A- weighted sound level is reported. Because of the time - varying nature of environmental sound, there are many descriptors that are used to quantify the sound level. Although one individual descriptor alone does not fully describe a particular noise environment, taken together, they can more accurately represent the noise environment. Descriptors that are commonly used in environmental studies include Lmax, Leq, L90 and Ldn and CNEL. The maximum instantaneous noise level (Lmax) is often used to identify the loudness of a single event such as a car pass -by or airplane flyover. To express the average noise level, the Leq (equivalent noise level) is used. The Leq can be measured over any length of time but is typically reported for periods of 15 minutes to one hour. The background noise level (or residual noise level) is the sound level during the quietest moments. It is usually generated by steady sources 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 2 of 25 10 October 2018 such as distant freeway traffic. It can be quantified with a descriptor called the L90 which is the sound level exceeded 90 percent of the time. Type of Noise or Envirorunent Decibels Rccorchtig stuchc) 20 Soft whisper.; quiet hedroon) 30 Busy open-plan office 55 Norm.d colivei- satioll 60 -65 Automobile 7t 101111J11 'IJ1t. lfm.l" 65 Vacuum cleaner 101i..7r1 w 70 Dimil) truck 7t - 0111] -11 ,5'011. 1 MIV 90 Gas leaf blower 7t 1) li. iiimv 100 Helicopter 900A.7rrm- 100 TI �Rln honi 100 A. MEM' 105 Cla, 11milller93'et WLeoll -90011. 7rf 1T" 120 Sho tglul It S11 dOf(1' S C'u- 140 To quantify the noise level over a 24 -hour period, the Day /Night Average Sound Level (Ldn or DNL) or Community Noise Equivalent Level (CNEL) is used. These descriptors are averages like the Leq except they include, by definition, a ten dBA "penalty" for noises that occur during nighttime hours (10 p.m. to 7 a.m.) to account for people's sensitivity to intrusive noise during these hours. The CNEL also includes a five dBA "penalty" during evening hours (7 p.m. to 10 p.m. to account for peoples' increased sensitivity during these hours (American National Standards Institute, ANSI S1.1 -1994, Acoustical Terminology, 1994). Community Response to changes in noise levels: The potential for adverse community response tends to increase as an intrusive noise becomes more noticeable above existing background noise levels. For example, if an intrusive noise has an average level that is comparable to existing average ambient noise levels, then the intrusive sound would tend to blend in with the ambient noise. However, if the intrusive sound is significantly greater than the ambient noise then the intrusive sound would be more noticeable and potentially more annoying as it can interfere with rest, working efficiency, social interaction and general tranquility. In general, human sound perception is such that a change in sound level of 3 dB is just noticeable, a change of 5 dB clearly noticeable and a change of 10 dB is perceived as a doubling (or halving) of loudness (Cowen, Handbook of Environmental Acoustics, 1994). 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis 3 Regulatory Framework 3.1 City of South San Francisco General Plan Page 3 of 25 10 October 2018 The Noise Element of the South San Francisco General Plan has guidelines for noise and land use compatibility. These guidelines are summarized in Table 9.2-1. Table 9.2-1: Land Use Criteria for Noise-impacted Areas Land Use CNEL Range Gmeneral Land Use, Criteri-a R sidcntial Less dian 65 Satisfactory; 110 special j ns o I at ion requirements 63 to 70 Development requires analysis of noise ircdur [ion re-quircmenq and insulatifm as needed Over 70 Nvelopment should not 1%, twdertaken Conirnurcial Less than 70 Satisfactory-, 110 6pecial insulation requirements 70 to 80 Development requirQN analy-fis of noise reduction req uiremew s and noise insulation as needed Over 90 Airport- related dck.-ctopmcnt only-, sp-ecial noise insulatim- should be pro vidiud Industrial Less than 75 gatisfactury; no special insulation requirements 7 (1 �5 Nvelopment requires analysis of noisc Tcdur [ion requircmem, and noiw insulation as needed Over 85 Airport-rQlatQd development 0111Y6 SpeCial r0i'SC ill'.AlIaLikll- should be providrd Open Less than 75 Satisfactory-, 110 special insulation requirements Over 75 Avoid uses involving concentrations of people or animals tifjrfove On, of &wh Sao? Frtfnuisco General Shirt Xohre Elepnerrr. SF0 Aiq-w! Land Use Plan 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis 3.2 City of South San Francisco Municipal Code Page 4 of 25 10 October 2018 Chapter 8.32 of the City's Noise Ordinance specifies maximum permissible sound levels to be generated by any property within the City. The maximum allowable level is determined by the land use category of the receiving property. These levels are summarized in Table 8.32.030. The levels shown in Table 8.32.030 are applicable for noises that occur up to 30 minutes per hour. Higher noise levels are allowed, but for shorter periods of time. Section 8.32.050 (d) identifies a special provision which allows construction activities with a City permit between the hours of 8 a.m. to 8 p.m. on weekdays, 9 a.m. to 8 p.m. on Saturdays and 10 a.m. to 6 p.m. on Sundays and holidays. Other hours may be authorized by obtaining a permit, provided the construction meets at least one of the following requirements: 1. No individual piece of equipment shall produce a noise level exceeding 90 dB at a distance of 25 feet. If the device is housed within a structure or trailer on the property, the measurement shall be made outside the structure at a distance as close to 25 feet from the equipment as possible. 2. The noise level at any point outside of the property plane' of the project shall not exceed 90 dB. ' According to the City's Municipal Code Section 8.32.020, property plane means vertical plane including the property line which determines the property boundaries in space. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Table 8.32.030: Noise Level Standards Page 5 of 25 10 October 2018 Land Use Category Time Period Noise Level (dB) R-E, R-1 and R-2 10 p.m. -7 a.m. 50 zones or any single- 7 a. ni.-1 0 D family or duplex residential in a specific plan district R-3 and ID-C zones or 1Dl----.m.-7a-m. any multiple - family 7 a-m--1 0 p-m. residential or mixed residentiallcommercial in any specific plan district C -1, P-C, Gateway 0 p.m. -7 a- m. 6D and Oyster Point 7 a-m--1 0 p-m. 65 Marina specific plan districts or any commercial use in any specific plan district 1•111-1, P-1 Anytime 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Page 6 of 25 Appendix E - Noise Impact Analysis 10 October 2018 3.3 Airport Land Use Compatibility Plan The 2012 Comprehensive Airport Land Use Compatibility Plan for the Environs of San Francisco International Airport has guidelines for noise and land use compatibility. These guidelines are summarized in Table IV -1. The project site is located outside the CNEL 65 dB aircraft noise contour and within "Airport Influence Area B ". Since the project site is exposed to a CNEL of less than 65 dBA from aircraft, the project would be compatible with the aircraft noise environment according to ALUC Policy NP -2 which sets forth the noise /land use compatibility criteria utilized to determine the compatibility of proposed land uses located in the Airport noise compatibility zones. Office and business professional uses are compatible with CNEL levels through 75 dBA and over, and may be permitted without any special requirements related to the attenuation of aircraft noise. Table W -1 No sell-and Use Compatibility Criteria 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM COMMUNITY NOISE EQUIVALENT LEVEL (CNEL) LAND USE BELOW 4S dB 1 dB 70 -75 dB 75 d8 AND OVER Residential Residential, single family detached Y C N Iqi N Residential, multi - family and single family attached Y C N toi N Transient lodgings Y C C N Publi cll nstitutional Public and Private Schcals Y C N N Hospitals and nursing homes Y C N N Places of public assembly, including places of worship Y C N N Auditoriums, and concert halls Y C C N Libraries Y C C N Clutdoor music shells, amphitheaters Y N N N Recreational Outdoor sports arenas and spectator sports Y Y Y N Na— exhibits and -- Y Y N N Amusements, parks, resorts and camps Y Y Y N Golf courses, riding stables, and water recreation Y Y Y Y Commercial Offices, business and professional, general recoil Y Y Y Y Wholesale; retail building materials, hardware, farm equipment Y Y Y Y Industrial and Production Manufacturing Y Y Y Y Utilities Y Y Y Y Agriculture and forestry Y Y (A) Y (t) Y {c) Mining and fshmg, resource productuzn and extracuon Y Y Y Y Notes: CNEL = Cam munity Norse Equivalent Level, in A- weighted decibeEs Y IYen) = Land use and related structures campauble without restrictions. C (condiuonally rompauble) = Land use and related structures are permuted, prawded that sound nsulazion n provided to reduce rntenor noise levels from exterior sources to CNEL 4S de or lower and that an av,S u- easement rsgrznted m the Crty and County of Sari Francisco as operamr of SFD. See Pohry NP -l. N fNol = Land use and related etruaures are not campaube -. foJ Use is conditionally campauble only on an —sang lot of record awned only for reside.nuak use as of the efle-- date .(the ALUCP. Use must be sound - rnsuXated m achieve an indoor noise level of CNEL 45 d6 o.r less frem:exterdar sources. The property owners shall grant an avigaaon a :.ement m the C+ty .and County of San Francisco prior to issuance of a building permit for Ne proposed building or structure. If the proposed development is not built then, upon nonce by the loaf perrruning authority, SFG shaft record a route of termrnatron of the —gauon casement f81 R- id—ral buildings must be sound--tad m aeh +eve —d— rake level of CNEL 45 de or less from exteror sources. fd Accessory dwelling ornts are not tampauMe. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis 3.4 CEQA Guidelines Page 7 of 25 10 October 2018 In accordance with Section XI of Appendix G of the CEQA Guidelines, a proposed project could have a significant environmental impact if it would result in: a. exposure of persons to or generation of noise levels in excess of standards established in any applicable plan or noise ordinance, or applicable standards of other agencies; b. exposure of persons to or generation of excessive ground -borne vibration or ground - borne noise levels; c. a substantial permanent increase in ambient noise levels in the project vicinity above levels existing without the project; d. a substantial temporary or periodic increase in ambient noise levels in the project above levels existing without the project; e. exposure of people residing or working in the project area to excessive noise levels if the project is located within an area covered by an airport land use plan, or where such plan has not been adopted, within two miles of a public airport or public use airport; or f. exposure of people residing or working in the project area to excessive noise levels if the project is located in the vicinity of a private airstrip. 4 Existing Noise Environment The project site is located at the southeast corner of East Grand Avenue and Haskins Way with East Grand Avenue serving as the primary arterial road. The major noise sources affecting the study area are vehicular traffic, aircraft, and commercial /industrial activities. Land uses in South San Francisco east of the 101 are mostly limited to offices, commercial and light industrial. Noise sensitive land uses are typically defined as residences, schools, place of worship, and hospitals. There are childcare centers and a preschool along Gateway Boulevard and Allerton Avenue. The nearest child care center /pre - school to the project site is the Genentech Childcare facility currently under construction at 342 Allerton Avenue. This facility is more than 1,200 feet from the project site. There are also hotels along Gateway Boulevard, Forbes Boulevard, Grand Avenue, Mitchell Avenue, Airport Boulevard, and South Airport Boulevard. These hotels are located more than 4,000 feet from the project site. Surrounding land uses include one- to two -story industrial buildings to the west, industrial warehouses (zoned "Business Technology Park ") to the north, the Genentech campus buildings to the northeast, the South San Francisco Scavenger Company and Blue Line Transfer buildings to the east, and existing industrial buildings and the Bay Trail to the south. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 8 of 25 10 October 2018 Noise measurements were conducted from May 16 -18, 2018 to quantify the existing noise environment. These included long -term, 48 -hour, measurements at two locations (Location LT -1 and LT -2) and short -term, 15 minute, measurements at four locations (Location ST -1 to ST -4). The noise measurement locations are shown in Figure 1. Figure 1: Noise Measurement and Receiver Locations Source: Map data © 2018 Google The long -term noise measurements were made at two locations on the project's primary roadway on East Grand Avenue. At these locations, monitoring was done using a Larson Davis Sound Level Meter Model 820. Calibrations were checked with a Larson Davis Ca1200 calibrator. Generally, the major noise source at each monitor was traffic on East Grand Avenue. Aircraft flyovers were also clearly noticeable and contributed to the overall noise level. The long -term measurement at Location LT -1 was made on a utility pole near the north edge of the project site at 410 East Grand Avenue. The microphone was located approximately 12 feet above ground. At Location LT -1, in addition to noise associated with local traffic and aircraft flyovers, noise from construction at the nearby Genentech building as well as occasional idling trucks around the monitor also contributed to the noise levels. The measured average noise level was a CNEL of 70 dBA. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 9 of 25 10 October 2018 The long -term measurement at Location LT -2 was made on a light pole on East Grand Avenue between Gateway Boulevard and Forbes Boulevard. The purpose of the measurement at Location LT -2 was to give additional information on noise from traffic on East Grand Avenue and be located further from construction activities at the Genentech facility near the project site. The microphone was located approximately 7 feet from the edge of the roadway and 12 feet above ground. The measured average noise level was a CNEL of 75 dBA. The long -term noise measurement results are summarized in Table 1. Graphs showing the hourly noise levels at each monitoring location are shown in Figure 2 and Figure 3. Table 1: Long -term Noise Measurement Summary Figure 2: Long -term Noise Measurement Results at Location LT -1 110 T Q 100 m ,ay 00 a� J i 80 G fun 70 t 60 3 50 129] Lmax —Leq L33 0 0 0 e3 0 0 a ea a o o 0 0 0 o 0© 0 0 a a a 0 0 a 0 o 1P a cP cP a c_! c_! o a a a a o 0 o cP a s cP a o o a 9 1P 1P 9 m Ln N M r-� M 1 m Ln r• M r-� m n r< M r-� M 1 m Ln r• M 1 m Ln 4 4 1 N N 4 a WED THU FRI 5/16/18 5/17/18 5/18/18 Date /Time 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM Weekday Average Noisiest Weekday Hour Location CNEL Time Leq LT -1 70 8:00 AM — 9:00 AM 68 LT -2 75 3:00 PM — 4:00 PM 73 Figure 2: Long -term Noise Measurement Results at Location LT -1 110 T Q 100 m ,ay 00 a� J i 80 G fun 70 t 60 3 50 129] Lmax —Leq L33 0 0 0 e3 0 0 a ea a o o 0 0 0 o 0© 0 0 a a a 0 0 a 0 o 1P a cP cP a c_! c_! o a a a a o 0 o cP a s cP a o o a 9 1P 1P 9 m Ln N M r-� M 1 m Ln r• M r-� m n r< M r-� M 1 m Ln r• M 1 m Ln 4 4 1 N N 4 a WED THU FRI 5/16/18 5/17/18 5/18/18 Date /Time 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis 110 d 100 m 90 J i 80 G 70 t 60 50 K1 Page 10 of 25 10 October 2018 Figure 3: Long -term Noise Measurement Results at Location LT -2 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 9 9 a 9 9 0 0 0 0 0 a 0 0 9 a a o 0 0 0 r rr Ln r~ M ri r'n r m Ln r" n r'ri Ln r- M r1 rri ri m wa f-, M 1 M ui '-� r-� —I " " r-� 1 _� r-� " r_q 1 r-I WED THU FRI 5/16/18 5/17/18 5/18/18 Date /Time Short -term noise measurements were made at four locations using a Larson Davis Model 824 Sound Level Meter at a height of five feet above ground. Calibrations were checked with a Larson Davis CAL200 calibrator. The short -term measurements allowed for direct observation of the existing noise environment and non - traffic noise sources can be identified. Additionally, traffic was classified and counted for comparison with predicted modeling results. The short -term measurements were made from May 16 -18, 2018. The weather condition during the measurement period on May 16, 2018 was 65 degrees Fahrenheit and sunny, clear skies with calm winds while the weather condition during the measurement period on 18 May 2018 was 53 degrees Fahrenheit and cloudy skies with an estimated 17 to 20 mph winds. The short -term measurement at Location ST -1 was made at the setback of the sidewalk in front of the existing Copy Mill commercial business on Haskins Way. The short -term measurements at Location ST -2 were made approximately 5 feet from the existing building located at 400 East Jamie Street. The short -term measurement at Location ST -3 was made at the parking lot of 451 East Jamie Court (Parcel 015 - 012 -090), near its east property line. The short -term measurement at Location ST -4 was made 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 11 of 25 10 October 2018 approximately 12 feet from the road (East Grand Avenue) leading to the Genentech parking lot structure. At Location ST -4, there is a steel plate covering on the road which generated maximum noise levels up to 85 dBA when vehicles traveled over it. The short -term measurement results are summarized in Table 2. Table 2: Short -Term Noise Measurement Results Site Location Date and Time LeQ L5o Lmax Cars: 62 — 72, (64 — 67 typ.) On Haskins Med Trucks: 70 — 77 Way 16 ay Heavy Trucks: 69 — 79 ST -1 at setback of 11:20 AM 11:35 AM 67 61 Truck Brakes: 88 Jets: 61 — 62 typ. sidewalk Backup Beeper at Haskins Way /E. Jamie Ct Intersection: < 57 Cars: <54, 55 — 57 Med Trucks: 60, 64 16 May 2018 Heavy Trucks: 60 11:47 AM - 12:08 PM 61 59 Jets: 55 — 70 Construction (steady): 62 400 East Jamie Construction (cutting): 64 - 68 ST -2 Court Street Sweeper on Haskins: 60 — 62 Med Trucks: 54, 57 — 60 typ. 18 May 2018 66 55 Heavy Trucks: 61 - 64 2:47 PM - 3:02 PM Helicopter: 64, 76, 87 Parking Lot Car: 61 Cars: < 58 451 East Jamie Medium Trucks: 62, 65 Court parking lot 16 May 2018 Heavy Trucks, 76 - 77 ST -3 near east 12:17 PM - 12:33 PM 63 59 Loading activity: 62 — 65 Nearby Truck Idle: 57, 63, 70 property line Backup Beeper: 75 Jets: 62 — 64 On roadway leading to 16 May 2018 65 57 Genentech 12:17 PM - 12:33 PM Cars (w /o metal sheet cover): 58 — 62 ST -4 Parking Steel Plate Cover: 69 — 71 typ., 85 structure, Construction: 55 — 63 approx. 12 feet 18 Ma y 2018 Street sweeper: 83 from edge of 2:39 PM - 2:53 PM 67 57 road 1104 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Page 12 of 25 Appendix E - Noise Impact Analysis 10 October 2018 5 Impact Assessment 5.1 Construction Noise 5.1.1 Thresholds of Significance The City's Municipal Code promulgates criteria for construction noise based on hours of operation. Therefore, for the purposes of this assessment, construction noise is considered significant if it: • Occurs outside the allowable hours of operation or exceeds the special provisions of Municipal Code Section 8.32.050 (individual equipment exceeds 90 dB at 25 feet and 90 dB at any point outside the property plane) • Causes ambient noise levels to increase significantly at nearby noise sensitive receptors 5.1.2 Construction Noise Impact Phase 1 construction activities would last about 18 months and include the demolition of the existing building at 201 Haskins Way and the construction of a new office building, a surface parking lot, a parking garage, and a new building addition at 400 East Jamie Ct. Based on the Preliminary Phase 1 Development Plan ma P2, the demolition of the existing building and construction of the new buildings, at the nearest point, would be approximately 164 feet from the industrial buildings to the west across Haskins Way, 290 feet from the office /warehouse buildings to the north across East Grand Avenue, 340 feet from the Genentech office building to the northeast, and 290 feet from the South San Francisco Scavenger office building to the east. The nearest noise sensitive land use is the Genentech Childcare Facility at 342 Allerton Avenue currently under construction which is more than 1,200 feet away from project demolition and construction activities. At this time, no specific Phase 2 development is proposed, and it is uncertain when or if such development would occur. However, in order to provide a conservative (worst case) analysis of construction impacts for CEQA purposes, it is assumed for purposes of this analysis that Phase 2 construction would commence in 2021 (immediately after 2 201 Haskins Way Project Summary. 9 March 2018 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Page 13 of 25 Appendix E - Noise Impact Analysis 10 October 2018 completion of Phase 1 construction) and would occur over an 18 -month period. Phase 2 construction would not begin until existing uses are vacated. Phase 2 construction activities would include the expansion of the Phase 1 parking lot, the demolition of the existing buildings along East Grand Avenue, and the construction of a new office building. Based on the Preliminary Phase 2 Conceptual Development Plan map, the demolition of existing buildings and construction of the new buildings would be approximately 120 feet from the industrial buildings to the west across Haskins Way, 105 feet from the office /warehouse buildings to the north across East Grand Avenue, 200 feet from the Genentech office building to the northeast, and 100 feet from the South San Francisco Scavenger office building to the east. The nearest noise sensitive land use is the Genentech Childcare Facility at 342 Allerton Avenue currently under construction which is more than 1,000 feet away from Phase 2 demolition and construction activities. Table 3 shows reference noise levels at a distance of 50 feet for construction equipment expected to be used for the project. Table 3 also shows the calculated noise levels at a distance of 25 feet using a standard rate of 6 dB per halving of distance. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Table 3: Construction Equipment Noise Levels Page 14 of 25 10 October 2018 Construction Equipment Ref. Level dBA at 50 feet Adjustment for Distance at 25 feet Calculated Noise Level at 25 feet Backhoe 78 6 84 Compressor 78 6 84 Concrete Saw 90 6 96 Dozer 82 6 88 Dump Truck 76 6 82 Gradall 83 6 89 Flat Bed Trucks 74 6 80 Excavator 81 6 87 Vacuum Street Sweeper 82 6 88 Tractor 84 6 90 Front End Loader 79 6 85 Compactor (ground) 83 6 89 Scraper 84 6 90 Auger Drill Rig 84 6 90 Slurry Trenching Machine 80 6 86 Gradall 83 6 89 Generator 81 6 87 Pneumatic Tools 85 6 91 Welder /Torch 74 6 80 Pump 81 6 87 Crane 81 6 87 Concrete Mixer Truck 79 6 85 Man -lift 75 6 81 Roller 80 6 86 Paver 77 6 83 Table 4 and Table 5 show the calculated maximum instantaneous exterior noise levels from project - related construction equipment at the neighboring office /industrial land uses under Phase 1 and Phase 2, respectively. Table 6 shows the calculated maximum instantaneous exterior noise levels from project - related construction equipment under both Phase 1 and Phase 2 at the Genentech Childcare Facility. The calculated exterior noise levels are based on the methodology of the Federal Highway Administration's (FHWA) Roadway Construction Noise Model (2006) and 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 15 of 25 10 October 2018 include a factor for acoustical shielding provided by the existing buildings (where appropriate). Standard construction with the windows closed provides a noise reduction of approximately 25 dBA, therefore, the noise levels in Tables 4, 5, and 6 below would also be attenuated by 25 dBA for persons inside the neighboring buildings. Table 4: Construction Noise Levels at Adjacent Land Uses — Phase 1 Construction Equipment Maximum Noise Levels (Lm,,.) for Typical Construction Activities, dBA Industrial Buildings to the west Office /Warehouse buildings to the north Genentech Office Building to the northeast South San Francisco Scavenger Office Building Backhoe 68 58 56 56 Compressor 68 58 56 56 Concrete Saw 80 70 68 68 Dozer 72 62 60 60 Dump Truck 66 56 54 54 Gradall 73 63 61 61 Flat Bed Trucks 64 54 52 52 Excavator 71 61 59 59 Vacuum Street Sweeper 72 62 60 60 Tractor 74 64 62 62 Front End Loader 69 59 57 57 Compactor (ground) 73 63 61 61 Scraper 74 64 62 62 Auger Drill Rig 74 64 62 62 Slurry Trenching Machine 70 60 58 58 Gradall 73 63 61 61 Generator 71 61 59 59 Pneumatic Tools 75 65 63 63 Welder 64 54 52 52 Pump 71 61 59 59 Crane 71 61 59 59 Concrete Mixer Truck 69 59 57 57 Man -lift 65 55 53 53 Roller 70 60 58 58 Paver 67 57 55 55 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 16 of 25 10 October 2018 Table 5: Construction Noise Levels at Adjacent Land Uses — Phase 2 Construction Equipment Maximum Noise Levels (Lrr,aX) for Typical Construction Activities, dBA Industrial Buildings to the west (at 120 ft) Office Warehouse buildings ngs to the north Genentech Office Building to the northeast (at 200 ft) South San Francisco Scavenger Office Building Backhoe 70 67 66 59 Compressor 70 67 66 59 Concrete Saw 82 79 78 71 Dozer 74 71 70 63 Dump Truck 68 65 64 57 Gradall 75 72 71 64 Flat Bed Trucks 66 63 62 55 Excavator 73 70 69 62 Vacuum Street Sweeper 74 71 70 63 Tractor 76 73 72 65 Front End Loader 71 68 67 60 Compactor (ground) 75 72 71 64 Scraper 76 73 72 65 Auger Drill Rig 76 73 72 65 Slurry Trenching Machine 72 69 68 61 Gradall 75 72 71 64 Generator 73 70 69 62 Pneumatic Tools 77 74 73 66 Welder 66 63 62 55 Pump 73 70 69 62 Crane 73 70 69 62 Concrete Mixer Truck 71 68 67 60 Man -lift 67 64 63 56 Roller 72 69 68 61 Paver 69 66 65 58 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 17 of 25 10 October 2018 Table 6: Construction Noise Levels at Genentech Childcare Facility Construction Equipment Maximum Noise Levels (Lm.,),) for Typical Construction Activities, dBA Phase 1 Phase 2 Backhoe 45 47 Compressor 45 47 Concrete Saw 57 59 Dozer 49 51 Dump Truck 43 45 Gradall 50 52 Flat Bed Trucks 41 43 Excavator 48 50 Vacuum Street Sweeper 49 51 Tractor 51 53 Front End Loader 46 48 Compactor (ground) 50 52 Scraper 51 53 Auger Drill Rig 51 53 Slurry Trenching Machine 47 49 Gradall 50 52 Generator 48 50 Pneumatic Tools 52 54 Welder 41 43 Pump 48 50 Crane 48 50 Concrete Mixer Truck 46 48 Man -lift 42 44 Roller 47 49 Paver 44 46 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 I FAX 415 464 0155 I €tGDACOUSTICS.COM 201 Haskins Way, South San Francisco Page 18 of 25 Appendix E - Noise Impact Analysis 10 October 2018 Construction - related activities would typically occur Monday through Friday, between 8 a.m. and 8 p.m., although some work is anticipated to occur on Saturdays between 9 a.m. and 8 p.m. or on Sundays between 10 a.m. and 6 p.m. According to the Municipal Code Section 8.32.050, the City does not place specific restrictions on noise emission during these hours. However, noise from construction activities would be noticeable at times at the neighboring buildings. For example, the measured outdoor ambient Leq along Haskins way (ST -1) is 67 dBA while the calculated maximum noise levels from construction activities are generally 3 to 8 dBA higher. The increase in average noise levels will depend on the duration of the construction equipment and the number of simultaneous activities. The nearest noise sensitive land use is the Genentech Childcare Facility at 342 Allerton Avenue. Based on the existing traffic volumes on East Grand Avenue and the distance between the facility and East Grand Avenue, the exterior noise levels due to traffic at the facility closest to the project site was calculated to be an Leq of 63 dBA. Table 5 shows that given the distance of at least 1,000 feet from the project site, the noise from project - related construction would generally be less than 55 dBA outdoors. This may be noticeable at times but is less than the noise levels generated by other intermittent ambient noise sources, such as traffic and aircraft. Construction activities are allowed by the City's code during regular business hours provided that noise from individual equipment does not exceed 90 dBA at 25 feet or that noise at any point outside the property plane does not exceed 90 dBA. Table 3 shows that all the individual construction equipment would generate less than 90 dBA at a distance of 25 feet except for concrete saws and pneumatic tools. Pneumatic tools and concrete saws are expected to be primarily used at distances of more than 50 feet from the property plane. The noise level from a concrete saw or pneumatic tool would not exceed the property plane noise limit of 90 dBA at a distance of 50 feet or more from the property plane. However, there may be times when these could be used close to the property line. The louder of the two, the concrete saw, would only be used during the approximate 20 -day demolition phase for Phase 1 and Phase 2. Since there is a chance that the concrete saw and pneumatic tools could be used close to the perimeter of the site, they could exceed the property plane noise limit of 90 dBA. This is less than significant impact with Mitigation Measure NO -1 ( "Construction Noise Minimization and Mitigation "). Additionally, at the nearest noise sensitive land use (Genentech Childcare Facility), construction noise would be less than the noise levels generated by intermittent ambient 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 19 of 25 10 October 2018 noise sources and is not expected to cause a significant increase in the ambient noise level. Therefore, this is considered a less than significant impact. There is a potential for noise from construction of Phase 1 and Phase 2 to adversely affect neighboring office /warehouse buildings. There is also a potential for noise from construction during Phase 1 to affect existing Phase 2 area buildings (101 Haskins Way, 410 and 430 East Grand Avenue, and 451 East Jamie Court). Noise from construction during Phase 2 could also be disruptive to occupants of Phase 1 area buildings. Implementation of Mitigation Measure NO -1 ( "Construction Noise Minimization and Mitigation ") would reduce potential for annoyance to business operations at the neighboring office /warehouse buildings as well as Phase 1 occupants. This is considered a less than significant impact with mitigation. Construction noise is considered a less than significant impact with mitigation. Mitigation Measure NO -1: Construction Noise Minimization and Mitigation In order to minimize the potential impact associated with construction, the following is recommended: • All construction equipment shall be equipped with mufflers and sound control devices (e.g., intake silencers and noise shrouds) that are in good condition and appropriate for the equipment. • Maintain all construction equipment to minimize noise emissions. • Stationary equipment shall be located on the site to maintain the greatest possible distance to the existing office buildings, where feasible. • Use temporary noise barriers around noisier equipment, where feasible, when the noise ordinance limits cannot be achieved. • Unnecessary idling of internal combustion engines should be strictly prohibited. • Provide advance notification 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. • The construction contractor shall provide the name and telephone number an on- site construction liaison. If construction noise is found to be intrusive to the community (complaints are received), the construction liaison shall investigate the source of the noise and require that reasonable measures be implemented to correct the problem. • Schedule high noise - producing activities during times when they would be least likely to interfere with the noise sensitive activities of the neighboring land uses, when possible. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTICS.COM 201 Haskins Way, South San Francisco Page 20 of 25 Appendix E - Noise Impact Analysis 10 October 2018 5.2 Operational Noise 5.2.1 Traffic Noise The proposed project would influence existing and future traffic volumes. The following section describes the methodology of quantifying the increase in noise levels due to vehicular traffic with and without the project. 5.2.1.1 Thresholds of Significance Neither the CEQA checklist nor the City's General Plan specify a quantitative method for determining whether a project would cause a significant increase in noise. In general, an increase of 3 dBA is just noticeable, a change of 5 dBA is clearly noticeable and a change of 10 dBA is perceived as a doubling (or halving). In October 2009, an EIR for the Gateway Business Park Master Plan promulgated impact thresholds based on these increases. Therefore, for the purposes of this impact assessment, the following increases in traffic noise, based on the Gateway Business Park Master Plan EIR are considered to be significant: Project Impact: • 5 dBA or greater if the future noise level is within the normally acceptable range (CNEL 65 dBA or less for residences and child care; CNEL 70 dBA or less for offices and retail; CNEL 75 dBA or less for industrial land uses). • 3 dBA or greater if future noise level is above the normally acceptable range. Cumulative Impact: • 5 dBA or greater if the future noise level is within the normally acceptable range (CNEL 65 dBA or less for residences and child care; CNEL 70 dBA or less for offices and retail; CNEL 75 dBA or less for industrial land uses) AND the project's contribution is cumulatively considerable (greater than 1 dBA) • 3 dBA or greater if future noise level is above the normally acceptable range AND the project's contribution is cumulatively considerable (greater than 1 dBA). 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Page 21 of 25 Appendix E - Noise Impact Analysis 10 October 2018 5.2.1.2 Traffic Noise Calculation Methodology In order to calculate the increase in traffic noise due to the project, the existing and future traffic noise levels were calculated using the Federal Highway Administration's Traffic Noise Model (TNM 2.5) using traffic volumes3 from Kittelson & Associates, Inc. The model takes into account the vehicle class, speed, road surface, and distance. The TNM model calculates an Leq based on peak -hour traffic data at a distance of 50 feet from the roadway centerline. The CNEL was determined based on the difference between the peak -hour Leq and CNEL measured at the long -term monitoring locations. 5.2.1.3 Project Generated Traffic Noise Impact Traffic noise levels with and without the project are shown in Table 7 along with the increase in noise due to the project for two scenarios: • Phase 1 • Phase 1 Plus Phase 2 Table 7 shows that the increase in traffic noise would be less than 3 dBA for all roadways in the study area under the Phase 1 and Phase 1 & 2 buildout scenarios. For commercial and industrial uses, the increases in traffic noise levels due to the project are less than both the significant increase thresholds of 5 dBA if the future noise level is within the normally acceptable range and 3 dBA if the future noise level exceeds the normally acceptable range. Therefore, the increase in traffic noise due to the project is less than significant. For the child care centers /preschools along Gateway Boulevard (between Oyster Point Boulevard and East Grand Avenue) and Allerton Avenue in the study area, the existing and future traffic noise levels are above the normally acceptable range. The increases in traffic noise levels due to the project are less than the 3 dBA significant increase threshold. Therefore, the increase in traffic noise due to the project is less than significant. Increase in traffic noise due to the project is considered a less than significant impact. 3 Barlow, Julie T., SWCA Environmental Consultants. '201 Haskins Noise Analysis." Email to Alan Rosen, RGD Acoustics, Inc. 10 August 2018. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Table 7: Traffic Noise Levels with and without Project Page 22 of 25 10 October 2018 Roadway CNEL at 50 feet from Roadway Centerline, dBA Existing Plus Increase over Existing Plus Increase over Existing Phase 1 Existing Phase 1 & 2 Existing Oyster Point Blvd west of Gateway Blvd 75.2 75.2 0.0 75.3 0.1 east of Gateway Blvd 74.1 74.1 0.0 74.1 0.0 Gateway Blvd Oyster Point Blvd to East Grand Ave 70.4 70.5 0.1 70.5 0.1 East Grand Ave to Mitchell Ave 70.2 70.5 0.3 70.6 0.4 Grand Ave west of Airport Blvd 68.1 68.1 0.0 68.2 0.1 Poletti Way to East Grand Ave 69.7 69.9 0.2 70.0 0.3 East Grand Ave Dubuque Ave to Grand Ave 72.8 73.1 0.3 73.3 0.5 Grand Ave to Gateway Blvd 73.6 73.8 0.2 74.0 0.4 Gateway Blvd to Forbes Blvd 74.8 75.1 0.3 75.3 0.5 Forbes Blvd to Littlefield Ave 73.5 74.0 0.5 74.3 0.8 Littlefield Ave to Allerton Ave 74.4 74.9 0.5 75.2 0.8 Allerton Ave to Haskins Way 73.3 74.1 0.8 74.6 1.3 east of Haskins Way 68.0 68.0 0.0 68.0 0.0 Haskins Way south of East Grand Ave 68.9 70.8 1.9 71.8 2.9 Allerton Ave north of East Grand Ave 66.5 66.5 0.0 66.5 0.0 Littlefield Ave south of East Grand Ave 68.8 69.0 0.2 69.2 0.4 Forbes Blvd north of East Grand Ave 70.3 70.6 0.3 70.9 0.6 Harbor Way south of East Grand Ave 70.3 70.3 0.0 70.3 0.0 Airport Blvd north of Grand Ave 72.5 72.6 0.1 72.7 0.2 Grand Ave to San Mateo Ave 73.3 73.3 0.0 73.3 0.0 South Airport Blvd Mitchell Ave to US 101 NB ramp 73.5 73.6 0.1 73.7 0.2 US 101 NB ramp to Utah Ave 71.1 71.1 0.0 71.1 0.0 south of Utah Ave 73.4 73.4 0.0 73.5 0.1 San Mateo Ave west of Airport Blvd 71.4 71.4 0.0 71.4 0.0 Produce Ave south of San Mateo Ave 73.5 73.6 0.1 73.7 0.2 Utah Ave east of South Airport Blvd 72.9 73.0 0.1 73.1 0.2 Mitchell Ave east of Gateway Blvd 71.7 71.7 0.0 71.7 0.0 US 101 NB Ramps Off-rampto East Grand Ave 71.1 71.2 0.1 71.3 0.2 intersecting South Airport Blvd 73.4 73.5 0.1 73.5 0.1 1104 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis 5.2.1.4 Cumulative Traffic Noise Impact Page 23 of 25 10 October 2018 In the future, traffic will increase due to general growth in the area that is not directly related to the project. Table 8 shows the future traffic noise levels for the following scenarios: • Future without Project • Future with Project (Phase 1) • Future with Project (Phase 1 & 2). The future traffic volumes are based on the predictions for traffic in the year 2040. Table 8 shows that the increase in traffic noise from cumulative development would be less than 3 dBA for all roadways in the study area with the exception of Gateway Boulevard and sections of East Grand Avenue. At roadways with a cumulative increase of less than the threshold of 3 dBA, the increase in cumulative traffic noise due to the project is less than significant. For Gateway Boulevard and sections of East Grand Avenue (between Dubuque Avenue to Gateway Boulevard and east of Haskins Way), the increases in traffic noise levels due to cumulative development range from 3.0 to 3.8 dBA. However, the project's incremental contribution to the cumulative increase is less than 1 dB which is not cumulatively considerable. Therefore, the project's contribution to the cumulative increase is less than significant. The child care centers /preschools in the study area are located along Gateway Boulevard (between Oyster Point Boulevard and East Grand Avenue) and Allerton Avenue. Along Gateway Boulevard, the cumulative traffic noise increase is greater than the 3 dBA threshold, however, the project contribution is less than 1 dBA which is not cumulatively considerable. Along Allerton Avenue, the cumulative traffic noise increase is 1.9 dBA which is less than the 3 dBA threshold of significance. This is considered a less than significant cumulative impact. The proposed project, under Phase 1 or project buildout, would not contribute considerably to a significant cumulative operational traffic noise impact. No mitigation is necessary. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM 201 Haskins Way, South San Francisco Appendix E - Noise Impact Analysis Page 24 of 25 10 October 2018 Table 8: Cumulative Traffic Noise Levels with and without Project 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTIC5.COM CNEL at 50 feet from Roadway Centerline, dBA Increase: Project Increase: Project Roadway Future 2040 Future 2040 Existing to Future 2040 Existing to (Phase 1) (Phase 1 &2) Existing without Plus Phase 1 & Future Plus Project Plus Phase 1 Future Plus Contribution Phase 2 Phase 1 & Contribution Phase 1 to Increase Phase 2 to Increase Oyster Point Blvd west of Gateway Blvd 75.2 78.1 78.1 2.9 0.0 78.1 2.9 0.0 east of Gateway Blvd 74.1 76.2 76.2 2.1 0.0 76.2 2.1 0.0 Gateway Blvd Oyster Point Blvd to East Grand Ave 70.4 73.5 73.6 3.2 0.1 73.6 3.2 0.1 East Grand Ave to Mitchell Ave 70.2 73.6 73.7 3.5 0.1 73.8 3.6 0.2 Grand Ave west of Airport Blvd 68.1 70.5 70.5 2.4 0.0 70.5 2.4 0.0 Poletti Way to East Grand Ave 69.7 70.0 70.2 0.5 0.2 70.3 0.6 0.3 East Grand Ave Dubuque Ave to Grand Ave 72.8 76.5 76.6 3.8 0.1 76.6 3.8 0.1 Grand Ave to Gateway Blvd 73.6 77.0 77.1 3.5 0.1 77.2 3.6 0.2 Gateway Blvd to Forbes Blvd 74.8 76.0 76.2 1.4 0.2 76.4 1.6 0.4 Forbes Blvd to Littlefield Ave 73.5 74.7 75.0 1.5 0.3 75.3 1.8 0.6 Littlefield Ave to Allerton Ave 74.4 75.1 75.4 1.0 0.3 75.7 1.3 0.6 Allerton Ave to Haskins Way 73.3 74.4 74.0 0.7 -0.4 74.4 1.1 0.0 east of Haskins Way 68.0 71.0 71.0 3.0 0.0 71.0 3.0 0.0 Haskins Way south of East Grand Ave 68.9 69.1 70.8 1.9 1.7 71.6 2.7 2.5 Allerton Ave north of East Grand Ave 66.5 68.4 68.4 1.9 0.0 68.4 1.9 0.0 Littlefield Ave south of East Grand Ave 68.8 70.0 70.1 1.3 0.1 70.3 1.5 0.3 Forbes Blvd north of East Grand Ave 70.3 72.0 72.2 1.9 0.2 72.3 2.0 0.3 Harbor Way south of East Grand Ave 70.3 71.1 71.1 0.8 0.0 71.1 0.8 0.0 Airport Blvd north of Grand Ave 72.5 74.6 74.7 2.2 0.1 74.5 2.0 -0.1 Grand Ave to San Mateo Ave 73.3 74.2 74.3 1.0 0.1 74.3 1.0 0.1 South Airport Blvd Mitchell Ave to US 101 NB ramp 73.5 75.5 75.5 2.0 0.0 75.6 2.1 0.1 US 101 NB ramp to Utah Ave 71.1 72.2 72.2 1.1 0.0 72.2 1.1 0.0 south of Utah Ave 73.4 74.9 74.9 1.5 0.0 75.0 1.6 0.1 San Mateo Ave west of Airport Blvd 71.4 72.4 72.4 1.0 0.0 72.4 1.0 0.0 Produce Ave south of San Mateo Ave 73.5 75.5 75.6 2.1 0.1 75.6 2.1 0.1 Utah Ave east of South Airport Blvd 72.9 74.6 74.7 1.8 0.1 74.7 1.8 0.1 Mitchell Ave east of Gateway Blvd 71.7 73.7 73.7 2.0 0.0 73.7 2.0 0.0 US 101 NB Ramps Off-rampto East Grand Ave 71.1 71.1 71.2 0.1 0.1 71.3 0.2 0.2 intersecting South Airport Blvd 73.4 75.7 75.8 2.4 0.1 75.8 2.4 0.1 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 RGDACOUSTIC5.COM 201 Haskins Way, South San Francisco Page 25 of 25 Appendix E - Noise Impact Analysis 10 October 2018 5.2.2 Mechanical Equipment (HVAC) 5.2.2.1 Thresholds of Significance Mechanical equipment noise that exceeds the limits set forth in Table 8.32.030 of the City's municipal code is considered a significant impact. 5.2.2.2 Mechanical Equipment Noise Impact The proposed project buildings under Phase 1 and Phase 2 are expected to have mechanical equipment generally associated with building ventilation /air- conditioning units, ventilation fans, but may also include other process specific equipment and possibly emergency engine - generators. Much of the equipment would likely be located on the rooftops of the proposed buildings, or at -grade next to the buildings. However, at the time of this report, the details and locations of the mechanical equipment are not known and therefore, calculations of specific noise levels at surrounding uses cannot be made. According to the City's municipal code, maximum permissible sound levels from the project are determined by the land use category of the receiving property and the L50 noise standards are shown in Municipal Code Table 8.32.030. The large commercial systems that are often used in this type of building can generate high noise levels and therefore, they would have the potential to generate noise levels in excess of the City's municipal code requirement. Therefore, noise from mechanical equipment is considered a potentially significant impact. However, with the implementation of Mitigation Measure NO -2 (referred to as Mitigation Measure NO -3 in the EIR; "Mechanical Equipment Noise Requirements "), this impact would be reduced to a less than significant level. Mitigation Measure NO -2: Mechanical Equipment Noise Requirements Analysis of noise from the project's mechanical equipment must be conducted to determine if the equipment will comply with the City's municipal code requirements in Table 8.32.030 per section 8.32.030, and what, if any, noise control measures must be included in the design to meet the City's requirements. For example, the ambient noise at Location ST -1 was an L50 of 61 dBA at 11:20 AM (See Table 2). The requirement for a receiving land use that is industrial (M -1) is an L50 of 70 dBA. Therefore, the mechanical system would need to meet an L50 of 70 dBA at that time of day for the industrial uses to the west. Prior to issuance of building permit, the project applicant shall submit a report verifying that project mechanical equipment meets the noise levels required in Table 8.32.30. Typical noise control measures include barriers, enclosures, silencers and acoustical louvers at vent openings. 1100 Larkspur Landing Circle # 354 1 Larkspur, California 94939 1 TEL 415 464 0150 1 FAX 415 464 0155 1 €tG®ACOUSTIC5.COM