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4.6 – Noise Draft Environmental Impact Report February 2021 14800 W. Schulte Road Logistics Center 4.6-4 Table 4.6-1. Measured Noise Levels Receptor Location Date Time Leq (dBA) Lmin (dBA) Lmax (dBA) ST5 Northwest of Project site, adjacent to residence at 24142 Hansen Road 10/14/2020 2:21 p.m.–2:31 p.m. 64 54.3 80.3 ST6 West of Project site, adjacent to residence at 24365 Mountain House Parkway 10/14/2020 1:58 p.m.–2:08 p.m. 60.3 49.6 71.5 Source: Appendix E-1 Notes: Leq = equivalent continuous sound level (time-averaged sound level); Lmax = maximum sound level during the measurement interval; dBA = A-weighted decibels. 4.6.2 Relevant Plans, Policies, and Ordinances Federal There are no federal noise standards that would directly regulate environmental noise during construction and operation of the Project. The following is provided because guidance summarized herein is used for or pertains to the analysis. Federal Transit Administration Noise. In its Transit Noise and Vibration Impact Assessment Manual, the Federal Transit Administration (FTA) recommends a daytime construction noise level threshold of 80 dBA Leq over an 8-hour period (FTA 2018) when “detailed” construction noise assessments are performed to evaluate potential impacts to community residences surrounding a project. Although this FTA guidance is not a regulation, it can serve as a quantified standard in the absence of such limits at the state and local jurisdictional levels. Vibration. The FTA’s Transit Noise and Vibration Impact Assessment Manual also establishes vibration guidance for various land uses based on their potential for human annoyance and activity disruption. In general, and according to FTA guidelines, groundborne vibration of 75 VdB or greater would be considered potentially annoyin g. Vibration of 85 VdB or greater would likely be highly annoying and disruptive for most land uses (FTA 2018). These guidelines are generally used to evaluate the significance of operational effects from transit projects. However, these guidelines are referenced in this Environmental Impact Report for the purposes of quantitatively describing the levels of vibration that are typically considered disruptive. Typically, potential building and structural damages are the foremost concern when evaluating the i mpacts of construction -related vibration. Table 4.6 -2 summarizes the FTA’s vibration guidelines for building and structural damage. Table 4.6-2. Groundborne Vibration Damage Potential Building Category Vibration Damage (inches per second PPV) I. Reinforced-concrete, steel, or timber (no plaster) 0.5 II. Engineered concrete and masonry (no plaster) 0.3