75D - PH ZONING ORD AND CUP CALIFORNIA PALMS

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Noise monitoring was performed using a Quest Technologies Model 2900 Type 2 IntegratingAogging Sound Level Meter- The unit meets the American National Standards Institute (ANSI) Standard S1.4-1983 for Type 2, 1 International Electrotechnical Commission (IEC) Standazd 651 - 1979 for Type 2, and IEC Standazd 65I - 1979 for Type 2 sound level meters. The unit was field calibrated at 10:52 am. using a Quest 'T'echnologies (ZC-10 calibrator immediately prior to the fast set of readings. The calibration was then rechecked at 12:26 p.m. after the four "spot" readings and prior to an "in-room" 24-hour measurement and no meter `<driR" was noted. The accuracy of the cahbrator is maintained through a program established through the manuficturer and is traceable to the National Bureau of Standazds. The unit meets the requiremeirts of ANSI Standard 81.4-1984 and IEC Standard 942: 1988 for Class 1 equipment. j The study included four 15-minute, "spot" readings and one 24-hour "in-room" reading at the project site. For the four spat readings, the I,eq, Lorin, Lmax, Loz> Los, Lzs, and Lro values were recorded. As discussed above, the Leq ~ value is representative of the equivalent noise level or logarithmic average noise level obtained over the measurement period. The Lorin and Lmax represent the minimum and maximum root-mean-square noise levels obtained over a period of 1 second. The Loz, Los,. Lu, and Lso represent the values that aze exceeded 2, 8, 25, and 50 percent of the tune, or alternatively, 1, 5, 15, and 30 minutes per hour if the readings were extrapolated out to an hour's duration. The 24-hour measurement actually. consisted of 24 1-hour measurements. These 24 readings include the Leq, the Lio, the L9o, and the Lmax. The L recorded. The readin obtained alo ~' Loz, Los, Ins> and Lro for the entire 24-hour period are also g ng Harbor Boulevard (NR-3) was supplememed with simultaneous vehicle counts. These coums were obtained for modeling purposes (discussed below). Monitoring locations are shown in Figure 2 and the readings are included. in Table 3. Each reading is summarized below. TABLE3 NOISELEVEL MF 9.SUREMLc1yTS'' Monitoring L Location ~4 (d&4) Loz(d$.4) (dTilAl Las(di3A) Lso(dBA) Lorin Lmax 1.1 58.8 57.1 NR-2 56.0 59.7 58.1 56.7 55.7 50.9 63.8 NR-3 67.9 74.8 71.7 68.8 65.3 50.2 80.3 NR-4 61.2 65.7 63.9 62..1 60.4 56.7 70,3 NR-5 46.4 53.3 50.3 47.4 43.8 23.8 67.4 The Leq represems the equivalent sound level and is the muneric value of a constant level that over the given period of time transmits the same amrnmt of acoustic energy as the actual time-varying sound level. The Loz, Los, Lss, and Lso are the levels that are exceeded 2, 8, 25, and 50 percern of the time, respectively. Alternatively, these values represenrt the noise level that would be exceeded for 1, 5, 15, and 30 minutes during a 1-hour period. The Lorin and Lmax represent the minimum and maximum root-mean_squaze noise levels obtained over a period of 1 second. z Represents a cominuous, 24-hour reading. 7 75D-127