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EXHIBIT 2 <br />NOISE BACKGROUND AND MODELING DATA <br />Table 2 Tvoical Noise Levels <br />Common Outdoor Activities <br />Noise Level <br />(dBA) <br />Common Indoor Activities <br />Onset of physical discomfort <br />120+ <br />110 <br />Rock Band (near amplification system) <br />Jet Flyover at 1,000 feet <br />100 <br />Gas Lawn Mower at three feet <br />90 <br />Diesel Truck at 50 feet, at 50 mph <br />Food Blender at 3 feet <br />80 <br />Garbage Disposal at 3 feet <br />Noisy Urban Area, Daytime <br />70 <br />Vacuum Cleaner at 10 feet <br />Commercial Area <br />Normal speech at 3 feet <br />Heavy Traffic at 300 feet <br />60 <br />Large Business Office <br />Quiet Urban Dayfime <br />50 <br />Dishwasher Next Room <br />Quiet Urban Nighttime <br />40 <br />Theater, Large Conference Room (background) <br />Quiet Suburban Nighttime <br />30 <br />Library <br />Quiet Rural Nighttime <br />Bedroom at Night, Concert Hall (background) <br />20 <br />Broadcast/Recording Studio <br />10 <br />Lowest Threshold of Human Hearing <br />0 <br />Lowest Threshold of Human Hearing <br />Source: California Department of Transportation (Caltrans). 2009, November. Technical Noise <br />Supplement ('TeNS"). Prepared by ICF International. <br />Vibration Fundamentals <br />Vibration is an oscillatory motion through a solid medium in which the motion's amplitude can be described <br />in terms of displacement, velocity, or acceleration. Vibration is normally associated with activities stemming <br />from operations of railroads or vibration -intensive stationary sources, but can also be associated with <br />construction equipment such as jackhammers, pile drivers, and hydraulic hammers. As with noise, vibration <br />can be described by both its amplitude and frequency. Vibration displacement is the distance that a point on a <br />surface moves away from its original static position; velocity is the instantaneous speed that a point on a <br />surface moves; and acceleration is the rate of change of the speed. Each of these descriptors can be used to <br />correlate vibration to human response, building damage, and acceptable equipment vibration levels. During <br />construction, the operation of construction equipment can cause groundborne vibration. During the <br />operational phase of a project, receptors may be subject to levels of vibration that can cause annoyance due <br />to noise generated from vibration of a structure or items within a structure. <br />Vibration amplitudes are usually described in terms of either the peak particle velocity (PPV) or the root <br />mean square (RMS) velocity. PPV is the maximum instantaneous peak of the vibration signal and RMS is the <br />Nowwber 2016 Page 5 <br />75C-224 <br />