549.40 STANDARDS ESTABLISHED; ALLOWABLE LIMITS.
   Blasting operations shall be so conducted that ground vibrations measured at the nearest structure or building, neither quarry nor contractor owned or leased, except high tension lines, supporting towers and appurtenances, do not exceed a peak particle velocity of two (2) inches per second or its equivalent on any of the three (3) mutually perpendicular planes of motion, i.e. vertical, longitudinal or transverse, and noise levels do not exceed a sound pressure level of one hundred thirty (130) dB peak. No blasting operation shall be permitted adjacent to any structure which the Planning Commission may deem hazardous.
   (a)   A record of the seismic wave pattern shall be kept for a minimum period of three (3) years after project completion by the seismologist and the same shall be filed in the permanent records of this City.
   (b)   No blasting shall be permitted unless the seismologist is present.
   (c)   When the characteristics or environment of any specific blasting event have been determined to be extraordinarily hazardous by the seismologist and Planning Commission, additional safety precautions may be lawfully required. The permittee shall be advised of the nature of such extraordinary hazard and instructed as to what additional safety requirements are required.
      (Ord. 1396. Passed 8-13-92.)