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Table N-1: Reference Noise Levels <br />Noise Source <br />Duration <br />(hh:mm:ss) <br />Ref. <br />Distance <br />(Feet) <br />Noise <br />Source <br />Height <br />(Feet) <br />Hourly <br />Activity <br />(M[nS)7 <br />Reference Noise <br />Level dBA 1.5o <br />@ Ref. <br />Dist. <br />@ 50 <br />Feet <br />Roof -Top Air Conditioning Unit' <br />960000 <br />5' <br />5' <br />39 <br />74.4 <br />54.4 <br />Trash Enclosure Activit 2 <br />000032 <br />5' <br />5' <br />60 <br />69.0 <br />49.0 <br />Pad -Mounted Transformer3 <br />3 <br />6' <br />5' <br />60 <br />56.0 <br />37.6 <br />Parking Lot VehicleMovements4 <br />010000 <br />10, <br />5' <br />60 <br />44.0 <br />33.5 <br />Courtyard Activit 5 <br />00:08:00 <br />10' <br />4' <br />60 <br />73.8 <br />59.8 <br />Outdoor Pool/Spa Activi <br />00:10:00 <br />5' <br />4' <br />60 <br />68.7 <br />48.7 <br />Roof -To Parkin 4 <br />00:10:00 <br />5' <br />4' <br />60 <br />68.7 <br />48.7 <br />Source: Urban Crossroads, 2019. Attachment A. <br />As measured by Urban Crossroads, Inc. on 7/2712015 at the Santee Walmart located at 170 Town Center Parkway. <br />2 As measured by Urban Crossroads, Inc. on 51312018 at a commercial and office park trash enclosure in the City of Costa Mesa. <br />Source: NEMA TR 1-2013 Transformers, Step Voltage Regulators and Reactors, Table 2 sound level for a 500 kVA transformer. <br />4 As measured by Urban Crossroads, Inc. on 8/24/2016 in the parking lot of the Windemere Apartment community in the City of Riverside. <br />5 As measured by Urban Crossroads, Inc. on Saturday night, September 21, 2019 in the City of Newport Beach. <br />6 As measured by Urban Crossroads, Inc. on 71512017 at the Covenant Hill Clubhouse pool in Ladem Ranch. <br />7 Anticipated duration (minutes within the hour) of noise activity during typical hourly conditions expected at the Project site based on the <br />reference noise level measurement activity. <br />Table N-2 identifies that the operational noise from the Project would range from 31.4 to 46.9 dBA L5o at the sensitive <br />off -site receiver locations. These operational noise level calculations are based on the reference noise level <br />measurements in Table N-1 and include barrier attenuation provided by intervening structures between each noise <br />source and the receivers, which are shown in Figure 15. These noise levels also assume the worst -case with the roof- <br />top air conditioning units, trash enclosure activity, pad -mounted transformers, parking lot vehicle movements, outdoor <br />courtyard activity, outdoor pool/spa activity and roof -top parking activities all operating simultaneously. In reality, the <br />noise sources would most likely not occur simultaneously and would vary throughout the day. <br />Table N-2: Project Operational Noise Levels <br />Receiver Location <br />Noise <br />Source <br />Project <br />0 erational Noise Levels dBA <br />L50 <br />30 mins <br />L25 <br />15 mins <br />Le <br />5 mins <br />L2 <br />1 min <br />Lm.. <br />e1 min <br />Air Conditioning Unit Roof -To <br />15.6 <br />17.3 <br />18.6 <br />18.9 <br />19.4 <br />Trash Enclosure Activity <br />27.7 <br />33.7 <br />40.7 <br />45.7 <br />47.2 <br />Pad -Mounted Transformer <br />14.8 <br />0.0 <br />0.0 <br />0.0 <br />0.0 <br />Parking Lot Veh. Movements <br />20.4 <br />23.4 <br />31.4 <br />37.4 <br />45.0 <br />R7 <br />Courtyard Activity <br />36.8 <br />39.0 <br />41.5 <br />43.9 <br />46.6 <br />Outdoor Pool/Spa Activity <br />28.1 <br />31.1 <br />34.4 <br />37.5 <br />42.9 <br />Roof -Top Parking <br />9.4 <br />12.4 <br />20.4 <br />26.4 <br />34.0 <br />Combined Noise Level: <br />37.9 <br />40.7 <br />44.8 <br />48.7 <br />51.8 <br />Air Conditioning Unit Roof -To <br />20.7 <br />22.4 <br />23.7 <br />24.0 <br />24.5 <br />Trash Enclosure Activity <br />13.4 <br />19.4 <br />26.4 <br />31.4 <br />32.9 <br />Pad -Mounted Transformer <br />28.0 <br />0.0 <br />0.0 <br />0.0 <br />0.0 <br />Parking Lot Veh. Movements <br />32.4 <br />35.4 <br />43.4 <br />49.4 <br />57.0 <br />R2 <br />Courtyard Activity <br />42.3 <br />44.5 <br />47.0 <br />49.4 <br />52.1 <br />Outdoor Pool/Spa Activity <br />31.6 <br />34.6 <br />37.9 <br />41.0 <br />46.4 <br />Roof -Top Parking <br />14.4 <br />17.4 <br />25.4 <br />31.4 <br />39.0 <br />Combined Noise Level: <br />43.2 <br />45.4 <br />49.0 <br />52.8 <br />58.6 <br />Air Conditioning Unit Roof -To <br />22.4 <br />24.1 <br />25.4 <br />25.7 <br />26.2 <br />R3 <br />Trash Enclosure Activity <br />14.4 <br />20.4 <br />27.4 <br />32.4 <br />33.9 <br />Pad -Mounted Transformer <br />24.7 <br />0.0 <br />0.0 <br />0.0 <br />0.0 <br />