Appendix A Noise Study Report - Laserfiche WebLink

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Chapter 8. Construction Noise Two types of short-term noise impacts would occur during construction of the proposed Project. The first type would be from construction crew commutes and the transport of construction equipment and materials to the project site that would incrementally raise noise levels on access roads leading to the site. The pieces of heavy equipment for grading and construction activities will be moved on site, will remain for the duration of each construction phase, and will not add to the daily traffic volumes in the project vicinity. A high single -event noise exposure potential at a maximum level of 84 dBA Lm,,x from trucks passing at 50 ft will exist. However, the projected construction traffic volume will be minimal when compared to existing traffic volumes on Fairview Street and other adjacent roadways, and the associated long-term noise level change will not be perceptible. Therefore, short-term construction -related worker commutes and equipment transport noise impacts would be less than substantial. The second type of short-term noise impact is related to noise generated during roadway construction. Construction is performed in discrete steps, each of which has its own mix of equipment and, consequently, its own noise characteristics. These various sequential phases would change the character of the noise generated and the noise levels in the project area as construction progresses. Despite the variety in the type and size of construction equipment, similarities in the dominant noise sources and patterns of operation allow construction -related noise ranges to be categorized by work phase. Table 8.1 lists typical construction equipment noise levels (Lmax) recommended for noise impact assessments based on a distance of 50 ft between the equipment and a noise receptor. Typical noise levels at 50 ft from an active construction area range up to 88 dBA L n x during the noisiest construction phases. The site preparation phase, which includes grading and paving, tends to generate the highest noise levels because the noisiest construction equipment is earthmoving equipment. Earthmoving equipment includes excavating machinery (e.g., backfillers, bulldozers, and front loaders). Earthmoving and compacting equipment includes compactors, scrapers, and graders. Typical operating cycles for these types of construction equipment may involve 1 or 2 minutes of full -power operation followed by 3 or 4 minutes at lower power settings. Fairview Street Improvements from 9th Street to 16th Street 51 and Bridge Replacement Project Noise Study Report