It is unlawful and an offense for any person to use or operate in connection with the drilling or reworking of any well within the corporate limits of the city, any wooden derrick or any steam-powered rig, or any engine unless it is equipped with adequate mufflers. The drilling rig or derrick shall be removed from the premises within thirty days from the date of completion of the well, and thereafter, when necessary, such completed well shall be served by portable rigs, which shall be removed when well is abandoned and plugged or completed as a producer and enclosed as herein provided, the permittee shall keep a watchman on duty on the premises at all times when other workmen of permittee are not on such premises. (Ord. 415 Exh. A (part), 1998)