Blasting is generally not permitted within 100 feet of a bridge. When blasting is to be performed, the following criteria must be adhered to:
(A) Before any blasting is permitted, the contractor, accompanied by a representative of the County Roads Department must inspect the existing structure, photographing, marking and noting any cracks, fractures, and/or other signs of existing damage. After the completion of the blasting, the structure is to be re-inspected by the contractor together with a representative of the County Roads Department. Any enlargement of existing cracks, new cracks or other damage to the structure must be considered to have been caused by the contractor's blasting. This additional damage must be repaired or replaced at the contractor's expense. These repairs must be made to the satisfaction of the County Roads Department.
(B) A seismograph is to be placed on the pier or abutment footing nearest to the point of blasting. The seismograph is to be operated by a person qualified to read and interpret the information obtained.
(C) Test shots using small charges and time delays are to be set off, noting the particle velocity as recorded by the seismograph. A maximum of 2 inches per second will be permitted.
(D) The sizes and time delays of the main shots will be determined by the test shots, bearing in mind that the particle velocity shall not exceed 2 inches per second.
(E) Even though the County Roads Department specifies the maximum readings on the seismograph, this does not relieve the contractor of responsibility for any damage sustained by the structure.
(Ord. —, passed 6-30-2009) Penalty, see § 54.99