It shall be unlawful for any person to use or operate in connection with the drilling or reworking of any well within the city any wooden derrick or any steam powered rig; or to permit any drilling rig or derrick to remain on the premises or drilling site for a period longer than sixty (60) days after completion or abandonment of the well. All engines shall be electrically powered by electricity produced by a regulated public utility. All rigs must be of a type using mud as a drilling fluid. Permittee shall keep a watchman on duty on the premises at all times from the start of the erection of the derrick, or a mast, or gin pole, until the well is abandoned and plugged, or completed as a producing well and enclosed within a fence as required in this title. Provided, it shall not be necessary to keep an extra watchman on duty on the premises when other workmen of permittee are on the premises. Provided further, the commission may waive the requirement of a watchman, and/or may require that only rotary mud drills be used. (Ord. 1939 § 4, 2009)