SU0004149 - Laserfiche WebLink

Home Browse Search

. .� Table 4.6-1 Ambient Noise Survey Results !� DSS Quarry Project - San Joaquin County - March 12, 1997 �•, Average Noise Levels Maximum Noise Levels Location . Daytime Nighttime Daytime Nighttime Ldw dB Site A 46 44 64 .62 Site 13 52 51 65 65 57 __] Note: The noise levels cited in this table are the averages of all the respective daytime and nighttime hours. Figures 4.6-2 and 4.6-3 illustrate the actual measured noise levels on an Dour-by-hour basis. The project area is served by Interstates 5 and 580, State Route 132, and Bird, Koster, Biewett and Gaffery Roads. Although sound levels from m individual vehicle passbys on these roadways are similar given similar travel speeds, the roadways with higher traffic volumes generate higher average noise levels (Leq). Existing traffic volumes on the local i ' roadways in the immediate project vicinity are low (Bird, Blewett and Koster Roads). As a result, average noise levels associated with traffic on these roadways are low. A complete tabulation of existing and project-related traffic noise levels on the area roadways is provided later in this section under the impact analysis discussion. ' There are two existing residences in the general project vicinity, not including the on-site residence which is proposed for relocation under all quarry excavation alternatives (1, 2, i and 3). Those residences, which are identified on Figure 4.6-1, are generally located to the southeast and southwest of the project site. The analysis of noise impacts associated with this project will focus on these nearest potentially affected noise-sensitive uses. ! p' � I I C REGULATORY SETTING II � The San Joaquin County Noise Ordinance, (Chapter 16, Section 9-3800) states that no .F sound level shall exceed 65 d13 Lar,at the property line of properties which abut areas either developed residential, zoned residential, or shown for residential use in the General Plan. The 65 dB Ldp standard would also apply to the property lines of parks, schools, hospitals, and rest homes. -For uses which are not particularly noise sensitive, such as commercial and industrial zones, the sound levels are not to exceed 75 dB La„ at the property line. As defined in Section 7.4, L_dn is the average equivalent sound level during a 24-hour day, obtained after addition of ten decibels to sound levels during nighttime periods. In the r analysis conducted for this EIR, ' Ldn levels were computed from hourly Leq levels, which can be measured accurately; and by applying the appropriate ten decibel penalty to levels occurring during.nighttime hours. r �i I Draft Environmental Impact Report 4-87 ER-96-3