2014-069 - Final Environmental Impact Report No. 2014-01

Home Browse Search

HARBOR BLVD. MIXED USE TRANSIT CORRIDOR PLAN FINAL FIR CITY OF SANTA ANA 5. Environmental Analysis NOISE would result in different noise levels at a given sensitive receptor. Heavy equipment, such as a dozer or a loader, can have maximum, short duration noise levels in excess of 80 dBA at 50 feet from the equipment. The average noise levels at noise - sensitive receptors would be much lower because noise from construction equipment is intermittent and diminishes at a rate of at least 6 dB per doubling distance, and because mobile construction equipment would move around the site and be operated with different loads and power requirements. Although the Harbor Corridor Plan would take several years to build out, it is anticipated that exposure of individual receptors to elevated construction noise levels would be for much shorter periods (e.g., a few months). Furthermore, construction of new residential and nonresidential land uses would depend on market conditions, resulting in intermittent construction activities in the project area. Construction noise impacts would depend on the distance from the receptor to the location of individual construction activities and on the presence of intervening structures. The specific locations, duration, and equipment required for individual projects are unknown. Therefore, it cannot be specifically determined how noise - sensitive uses in the project area and surroundings would be affected. Construction of individual developments associated with buildout of the Harbor Corridor Plan would temporarily increase the ambient noise environment at nearby existing and future residential areas, churches, and parks. At each individual receptor, the temporary increase would likely last for a few months. The City of Santa Ana exempts noise associated with construction, repair, remodeling, or grading of any real property from the noise limitations of the municipal code, provided that construction activities do not take place between the hours of 8:00 PM and 7:00 AM on weekdays, including Saturdays, or any time on Sundays or federal holidays. Even with these time- of-day constraints, construction activities associated with any individual development may occur in dose proximity to noise sensitive receptors, and noise disturbances may occur for prolonged periods of time. Therefore, construction noise impacts are considered potentially significant. 5.9.6 Cumulative Impacts Cumulative noise impacts occur when multiple sources of noise, though individually not substantial, combine to result in excessive, cumulative noise exposure at noise sensitive uses. Short -Term Construction Noise and Vibration Cumulative construction noise impacts have the potential to occur when multiple construction projects in the same general area generate noise within the same time frame and contribute to the increases in the ambient noise environment. Based on noise levels generated by construction activities associated with the project site, the duration of construction activities that would occur intermittently within the approximately 20 -year buildout period, and the proximity of the sensitive receptors, construction noise from the project could substantially elevate ambient noise levels. This would significantly contribute to the cumulative noise environment. Cumulative construction noise impacts are considered potentially significant. October 2014 Page 5.9 -19