EXHIBIT 4-1_55A_BRISTOL WIDENING EIS-EIR

Home Browse Search

The construction noise impacts to the surrounding community could be significant, albeit short -lived. Residences, schools and other noise- sensitive land uses are most likely to be adversely affected by construction - related noise. Construction activities will take place only during daytime hours to avoid evening and nighttime noise nuisances and minimise impacts to residential properties. Noise will subside to normally expected levels once construction is complete. While the impact of project construction activities upon ambient air quality is considered to be insignificant, the localized effects of fugitive dust and odors may present a nuisance to adjacent properties during the period of construction. Large dust particles (30 -100 microns in diameter) that may settle to earth within a few hundred feet of the construction area could create a temporary localized nuisance problem. Additionally, fine- grained particulates (less than 30 microns in size) may be emitted and dispersed over greater -- distances, occasionally annoying adjacent receptors, especially during Santa Ana wind conditions. Dust generation is usually only a problem in construction activities which involve substantial site grading or require vehicles to travel over unpaved roadways. Construction of the proposed project should require very little earth movement at any one location and virtually no travel over unpaved roadways. Dust generation is expected to be minimal. .M Diesel construction equipment constitutes approximately 90 percent of the heavy construction machinery in use today. It emits on the average about one - half pound of NOx (and smaller amounts of CO and THC) for each gallon of fuel burned (EPA, AP -42). Construction equipment emission rates on very active days mar total several hundred pounds of contaminants per hour. The concentration of carbon soot in the exhaust of diesel engines makes the smoke plume highly visible and acts as a minor contributor to the nuisance caused by particulates. The odor associated with diesel emissions is believed to be caused by combinations of unburned fuel and a 'number of various chemicals in the exhaust gas. Exhaust emissions during the construction activities will vary from day -to -day as construction activity levels change but should be al and dispersed without significant impact on sensitive receptors. The construction activities required to widen the roadway may temporarily - restrict traffic flow along Bristol Street. While the roadway will remain open _ to through traffic, the number of available travel lanes will probably be reduced during various phases of construction, thereby reducing the capacity and efficiency of the roadway. For this reason, the volume of traffic which Bristol Street can handle efficiently will be decreased during the period of project construction. Since this would result in an increase in travel time along Bristol Street, some motorists will probably choose to take an alternative route when convenient. Access to property fronting along Bristol Street will also be intermittently disrupted as work progresses adjacent to individual " IV -78