Noise associated with surface mining may constitute a nuisance or a public health concern, therefore, when surface mining activity is within or adjacent to a Rural or Residential zone, hours of operation for excavating, processing, and loading shall be prohibited on Sundays and the legal holidays of Christmas Day, New Year's Day, Memorial Day, 4th of July, Labor Day, and Thanksgiving, and limited to between 6:30 a.m. and 5:30 p.m. Monday – Saturday; provided, that the surface mining operation may continue beyond the stated time if the noise created is less than the ambient night time noise levels for that area; and further provided, that the following activities are exempt from these requirements:
(a)
Excavation and loading during and connected to flooding emergencies, and
(b)
Early morning (5:00 a.m.) processing of ready mix concrete as necessary to provide beneficial concrete strength (exempt Monday through Saturday only), and
(c)
Early morning (5:00 a.m.) work in preparation for hot mix asphalt production and loading (exempt Monday through Saturday only), and
(d)
Activity under public contract when in the public interest.