SITE INFORMATION AND CORRESPONDENCE

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5.7 NOISE In most cases, environmental noise produces effects in the first two categories only. However,workers in industrial plants may experience noise effects in the last category. No completely satisfactory way exists to measure the subjective effects of noise, or to measure the corresponding reactions of annoyance and dissatisfaction. This lack of a common standard is primarily due to the wide variation in individual thresholds of annoyance and habituation to noise. Thus, an important way of determining a person's subjective reaction to a new noise is by comparing it to the existing or"ambient" environment to which that person has adapted. In general,the more the level or the tonal (frequency) variations of a noise exceed the previously existing ambient noise level or tonal quality,the less acceptable the new noise will be, as judged by the exposed individual. Table 5.7-2 shows the relative A-weighted noise levels of common sounds measured in the environment and in industry for various sound levels. TABLE 5.7-2 Typical Sound Levels Measured in the Environment and Industry A-Weighted Noise Source Sound Level Subjective at a Given Distance in Decibels Noise Environments Impression Shotgun (at shooter's ear) 140 Carrier flight deck Painfully loud Civil defense siren (100 ft) 130 Jet takeoff(200 ft) 120 Threshold of pain Loud rock music 110 Rock music concert Pile driver(50 ft) 100 Very loud Ambulance siren (100 ft) 90 Boiler room Pneumatic drill (50 ft) 80 Noisy restaurant Busy traffic; hair dryer 70 Moderately loud Normal conversation (5 ft) 60 Data processing center Light traffic(100 ft); rainfall 50 Private business office Bird calls(distant) 40 Average living room, library Quiet Soft whisper(5 ft); rustling leaves 30 Quiet bedroom 20 Recording studio Normal breathing 10 Threshold of hearing Source: Beranek, 1998. 5.7.2 Affected Environment 5.7.2.1 Local Land Use and Noise Sources The proposed 4.4-acre power plant site is located on land owned and incorporated by the City of Lodi, approximately 6 miles west of Lodi,in San Joaquin County, California. The project site is adjacent to the City of Lodi s White Slough Water Pollution Control Facility (WPCF) to the east,treatment and holding ponds associated with the WPCF to the north,the existing 49 MW Northern California Power Agency (NCPA) Combustion Turbine Project#2 (STIG plant) to the west, and the San Joaquin County Mosquito and Vector SAC/371322/08234009(LEC_5.7_NOISE.DOC) 5.7-3