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110 2. Construction Scheduling. Ensure that noise-generating construction activity is limited to between the hours of 7:00 a.m. to 8:00 p.m., Monday through Friday, except when authorized by the Building Official (Redwood City Municipal Code Section 24.32). (Redwood City Municipal Code Section 24.30) 3. Construction Equipment Mufflers and Maintenance. Equip all internal combustion engine-driven equipment with intake and exhaust mufflers that are in good condition and appropriate for the equipment. 4. Equipment Locations. Locate stationary noise-generating equipment required on construction project sites as far as possible from sensitive receptors when sensitive receptors adjoin or are near a construction project site. 5. Construction Traffic. Route all construction traffic to and from the construction sites via designated truck routes to the maximum extent feasible. Prohibit construction-related heavy truck traffic in residential areas where feasible. 6. Quiet Equipment Selection. Use quiet construction equipment, particularly air compressors, wherever feasible. 7. Temporary Barriers. Construct solid plywood fences around construction sites adjacent to residences, operational businesses, or noise-sensitive land uses. 8. Temporary Noise Blankets. Temporary noise control blanket barriers shall be erected along building facades of construction sites to attenuate noise from elevated activities if noise conflicts cannot be resolved by scheduling. (Noise control blanket barriers can be rented and quickly erected.) 9. Noise Disturbance Coordinator. For projects that would last over one year in duration, the City may choose to require the Project Applicant to designate a “Noise Disturbance Coordinator” who shall be responsible for responding to any local complaints about construction noise. The Disturbance Coordinator shall determine the cause of the noise complaint (e.g., starting too early, bad muffler, etc.) and institute reasonable measures to correct the problem. The Project Applicant shall post, in a conspicuous location, a telephone number for the Disturbance Coordinator at the construction site and include it in the notice sent to neighbors regarding the construction schedule. (The Noise Disturbance Coordinator shall work directly with an assigned City staff member.) Operational Noise (Illingworth & Rodkin, pp. 27-34): Commercial Component operational noise would occur primarily as a result of rooftop mechanical equipment, truck loading and unloading, and project-generated traffic increases. The following mechanical equipment would be located on the project rooftop: an air-source heat pump chiller unit and a water-cooled chiller unit, and a cooling tower, though the site plans do not indicate precise location or quantity of this equipment. As indicated in the project component plans (Plan Sheet A2.07, 8/5/24), a mechanical “yard” enclosure would be included, presumably for screening some rooftop equipment, with the chiller “room” a separate enclosure inside this “yard” enclosure. The mechanical “yard” would extend 16-1/2 feet above the top of the roof (Plan Sheet A3.01, 8/5/24), subject to final design review and approval by the City, which would need to be completed prior to issuance of any building permit. Illingworth & Rodkin estimated equipment noise using conservative manufacturer’s specifications and assumptions for location and continuous operation hours. Based on these assumptions, total rooftop mechanical equipment noise levels would be 69 dBA Leq at 5 feet each hour in a 24- hour period, which would result in a community noise equivalent level of 76 dBA CNEL at 5 feet; on the south portion of the roof, noise levels would be 66 dBA Leq at 5 feet each hour and a community noise equivalent level of 73 dBA CNEL at 5 feet. Illingworth & Rodkin assumed a minimum 20 dBA attenuation from screening and determined that hourly average noise levels generated from rooftop mechanical equipment would not exceed daytime or nighttime ambient noise levels at the surrounding receptors, and noise level increases from the equipment at all existing receptors would not be measurable or detectable (e.g., a 0 dBA CNEL increase). And considering a setback of 10 feet from the edge of the rooftop, the distance of mechanical equipment to the nearest property line would be approximately 45 feet. Illingworth & Rodkin determined that with a 20 dBA attenuation for screening, the hourly average noise level at the property line would be 30 dBA Leq, which would be less than the Zoning Code 55 dBA threshold at the property line. Mechanical equipment noise impacts would be less than significant. Illingworth & Rodkin estimated truck loading/unloading activity noise for the north receptors, which would have some direct exposure to the Commercial Component’s loading area inside the building. The building façades would provide partial shielding, estimated at a minimum 5 dBA. Noise from truck delivery activities would include engine, exhaust, and tire noise; intermittent back-up alarms; and the release of air brakes. Maximum instantaneous noise from heavy trucks would typically range from 70 to 75 dBA Lmax at a distance of 50 feet. Backup alarm noise would vary depending type and direction of the alarm with maximum noise levels ranging from 65 to 75 dBA Lmax at a distance of 50 feet. Truck maneuvering for a single truck would reach up to 69 dBA Leq at 50 feet for an hourly average, which assumes a delivery would not occur for more than 15 minutes in a given hour. With up to four deliveries in a 24-hour period, between 7:00 AM and 7:00 PM, the community noise equivalent level would be 61 dBA CNEL at 50 feet. Hourly average noise levels generated by the truck loading and unloading activities would not exceed daytime ambient ATTY/RESO.0028/CC RESO CEQA GUIDLINES (920 SHASTA) - EXHIBIT A REV: 04-22-25 VR Page 110 of 148