(a) Blasting operations shall be so conducted that ground vibrations, measured at the nearest structure or building, do not exceed a peak particle velocity of two inches per second or its equivalent on any of the three mutually perpendicular planes of motion, i.e., vertical, longitudinal or transverse, and so that air blast overpressures do not exceed 130 dB peak linear. No blasting operation will be permitted within 150 feet of any dwelling, building, school, church, theater or any structure which the Director of Public Safety or City Seismologist may deem vulnerable to damage by such vibrations. Such measurement from the nearest structure or building, as described above, shall not apply to quarries or to the blasting of contractor-owned structures or buildings, whether owned or leased, or high tension lines and their supporting towers and appurtenances.
(b) Blasting operations conducted within the allowable limits of ground motion and particle velocity contained in this section must be nondamaging to structures.
(c) A record of the seismic wave pattern shall be kept by the City Seismologist for a minimum of three years after project completion, and the same shall be filed in the permanent records of the city.
(d) No blasting operations shall be permitted unless the City Seismologist is present.
(e) When the characteristics or environment of any specific blasting event have been determined to be extraordinarily hazardous by the City Seismologist and Director of Public Safety, additional safety precautions may be lawfully required. The permittee shall be advised of the nature of such extraordinary hazard and instructed as to what specific additional safety standards are required.
(Ord. 1988-192, passed 10-3-1988)