31A - 100 W. MACARTHUR BLVD. - Laserfiche WebLink

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a local general plan, specific plan or other land use plan? No Impact According to the City's General Plan Land Use Element EIR there are no areas in Santa Ana designated as significant Mineral Aggregate Resource Areas. Therefore, implementation of the proposed project would not result in the loss of any regionally or locally important mineral resource. XI. NOISE The proposed project has the potential to generate noise during project construction and operation, which may affect sensitive receivers within the project area. Noise impacts generated by the proposed project would be subject to noise standards established in the City's Municipal Code Noise Ordinance. Noise Regulations Noise is most often defined as unwanted sound. Sound pressure magnitude is measured and quantified using a logarithmic ratio of pressures, the scale of which gives the level of sound in decibels or dB. Typically, a 3dB increase over existing noise levels is perceptible to the human hearing system. The human hearing system is not equally sensitive to sound at all frequencies. Therefore, to approximate this human, frequency-dependent response, the A-weighting filter system is used to adjust measured sound levels. When sound is measured for distinct time intervals, the statistical distribution of the overall sound level during that period can be obtained. The energy-equivalent sound level, Leq, is the most common parameter associated with such measurements. The Leq metric is a single-number noise descriptor, which represents the average sound level over a given period of time. To account for the increased sensitivity of people to noise occurring at night, a number of noise metrics have been developed. Two of the more commonly used metrics are the Day-Night Sound Level (Ldn) and the Community Noise Equivalent Level (CNEL). The Ldn, which was developed by 19 3tA8~O