2014-028 - Approving General Plan Amendement No. 2014-01

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CW of Santa Ana -Park View at Town and Country Manor Noise Draft EIR Groundborne Vibration Groundbome vibration consists of rapidly fluctuating motions within the ground that have an average motion of zero. The effects of groundbome vibration typically cause a nuisance only to people, but at extreme vibration levels, damage to buildings may occur. Although groundbome vibration can be felt outdoors, it is typically an annoyance only indoors, where the associated effects of the shaking of a building can be notable. Groundbome noise is an effect of groundbome vibration and typically only exists indoors, since it is produced from noise radiated from the motion of the walls and floors of a room and may consist of the rattling of windows or dishes on shelves. Peak particle velocity (PPV) relates to the maximum instantaneous peak of the vibration signal and is often used in measuring the magnitude of vibration. Scientific studies have shown that human responses to vibration vary by the source of vibration: continuous or transient. Continuous sources of vibration include construction, while transient sources include truck movements. Generally, the thresholds of perception and annoyance are higher for transient sources than continuous sources. Table 4.5 -2 shows PPV levels for continuous and transient sources and the associated human response. Table 4.5 -2: Vibration Levels and Human Response Peak Particle Veloc Continuous econd) Transient 2.00 0.90 Human Response Severe Strongly perceptible 0.40 0.10 0.04 0.25 Distinctly perceptible 0.01 0.04 Barely perceptible Source: California Department of Manual, 2004. Transportation, Transportation -and Construction- Induced Vibration Guidance Existing Noise The noise environment within the project area is dominated primarily by vehicle traffic and community activity. The primary source of noise in the vicinity of the proposed project is vehicular traffic on Memory Lane, which runs along the eastern and southern boundaries of the project site, and on Lawson Way, which runs along the western boundary of the project site. Other sources include the City Place mixed use development across Lawson Way, Amtrak trains, and recreational uses at Santiago Park. Vehicular Traffic Noise Levels Future peak hour traffic noise levels were modeled using the Federal Highway Administration Noise Prediction Model (FHWA -RD -77 -108). The model calculates noise levels forvarying traffic volumes and speeds. Noise model output worksheets for existing conditions, year 2013, and year 2030 with and without the project are included as Appendix E. Modeling was conducted using data 4.5-4 Michael Brandman Associates H\ Clievt (PN- JN)b327b327WMDEMVB2]0030 Sec01 Noi�.