(a) Compliance with vibration and air overpressure limits herein shall not relieve the contractor of responsibility for adverse effects of blasting. In no case shall the limits for ground vibration and air overpressure specified herein be exceeded.
(b) The following limits shall apply at the location of any public, commercial, or institutional building, school, church, or residence:
(1) Air overpressure shall not exceed 133 dBL, as measured on the linear scale of a sound pressure level transducer located adjacent the structure.
(2) All blasting and construction operations shall be designed and constructed to result in Peak Particle Velocities and frequencies in any direction less than that allowed by the Office of Surface Mining (OSM) Method 3 (1983), Federal Register, Vol 48, No. 46, March 8) at any structure.
(c) Initial blasts shall be designed with a charge weight per delay to produce a minimum scaled distance of 50 ft/lb½ . For example, if the controlling structure is 100 feet from the blast, the maximum charge weight per delay shall not exceed 4 pounds [or ((100 ft)/(50 ft/lbs½))2].
(d) Blasting shall be restricted to the hours from 9:00 a.m. to 5:00 p.m., Monday through Friday. Schedule blasting to minimize disturbance of public, commercial, and government operations.
(Ord. 2005-5-4. Passed 5-3-05.)