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Section 2 t n;11 -, t',:,! k ri,:i,, ,i�d Ei�nnru;i� rtlal Cc�r r yue��te� a. Outdoor measurements were collected by CDM Smith using a Type 1 SounclPro DL sound level meter in October 2014. The noise meter was placed 5 feet above the ground level. Noise levels were measured at each location and the equivalent steady-state sound level (Leq) was collected for each site logged in one minute intervals. One minute data log is important to determine any aberrant noise events at each site. Noise levels were measured at six locations within the Project Study Area, as shown in Table 2-1. The purpose of the ambient noise level measurement was to quantify the existing acoustic environment and provide a baseline for assessing the impact of future noise levels on the receptors in the vicinity of the proposed action resulting from the Proposed Project. No documentation of field measurements collected by AAF were presented in the DEIS. Table 2-1 October 2014 Noise Data Collected by CDM Smith Crossing Location Measured (various time periods) Lmax Leq Lmin Ambient Leq Train Event Leq Train Horn Lmax Sebastian Roseland Rd 107 79 48 71 88 107 Sebastian Schumann Dr 104 74 42 64 88 104 Vero Beach 45th St 101 71 47 64 83. 101 Vero Beach 23rd St 105 78 52 64 86 105 Vero Beach 4th St 98 7653 68 86 98 Vero Beach Highland Dr 1 106 80 52 67 89 106 b. People generally perceive a 10 A -weighted decibel (dBA) increase in a noise level as a doubling of loudness. For example, a 70-dBA sound will be perceived by an average person as twice as loud as a 60-dBA sound. People generally cannot detect differences of 1 dBA to 2 dBA. Differences of 3 dBA can be detected by most people with average hearing abilities. A 5-dBA change would likely be perceived by most people under normal listening conditions. The DEIS underestimates the noise impacts from the Proposed Project. Table 5.2.2-9 of the DEIS, indicates that the Proposed Project would result in daytime noise levels (Leq) ranging from 62.1 to 63.9 dBA close to at -grade crossings (average 62.5 dBA) and ranging from 61.4 to 63.5 dBA along the mainline tracks. The 2014 ambient noise levels (L.eq) collected by CDM Smith in the field ranged from 61 to 71 dBA and 83 to 89 dBA during a train event for the existing condition. These values are higher than the projected background conditions used in the DEIS. The DEIS does not address different noise sources and combining of noise sources such as traffic noise, freight noise, and passenger train noise to calculate the increase in the noise levels from the Proposed Project which results in underestimation of noise levels from the vroiect d. The Ldn ranged from 62.2 to 64.1 at -grade crossings and 61.6 to 63.6 along the mainline. The future noise levels listed in Table 5.2.2-10 shows the existing Ldn noise levels are 75 dBA with the project noise at 64 dBA in Indian River County. Comparing existing Ldp from the existing levels of 62.2 to 64.1 to future levels of 75 dBA, there is a 10 dBA increase which equates to doubling of loudness 2 The DEIS fails to include existing vibration levels in the Project Study Area to compare to future vibration levels. Similarly, generic vibration levels at various distances are only shown for rubber -tired vehicles traveling at 30 miles per hour (mph), light rail traveling at 50 mph, and heavy rail traveling at 50 mph. As suggested by the DEIS, the vibration source in the E -W Corridor is SR 528, where vehicles in the Project Study Area will be traveling at speeds exceeding 30 mph. According to a later reference on CDM Smith 301 •y c7 2-5