The objective of the work described in this paper was to formulate a quantitative assessment of the noise environment adjacent to a segment of I-78 before, during, and after construction of the roadway. Existing noise levels were taken at 10 sites to establish a baseline for comparison with construction noise levels and traffic noise levels. These ambient noise levels ranged into the low 50s for all sites. During construction, four sites experienced no noise impacts, one site was severely affected, and the remaining five sites were intermittently affected by noise during various construction activities. When traffic noise was measured with noise barriers in place, seven sites were not affected, one site was moderately affected, and noise levels at two of the sites increased significantly in comparison to the preconstruction noise levels. At 9 of the 10 sites, the highest single l sub eq measured was generated during the initial phases of construction. Clearing, cut and fill, and rough grading operations were the major sources of noise at all sites. Drainage installation, bridge work, construction of retaining walls, and rock drilling were secondary sources of noise. The only activity that caused a sustained increase over the existing noise levels was hauling. The noise from this operating dominated other construction noises for the duration of the project.
Samenvatting