In every case where workers are employed by owners of lots to do work or make improvements in or about said lots, such workers shall be subject to the control and direction of the mayor; and any worker who shall neglect or refuse to obey said direction, or who shall carelessly or wilfully do injury to adjacent lots, or who shall neglect to remove any rubbish accumulated in his work, will not thereafter be permitted to work in the grounds of the cemetery. (1983 Code § 2.24.060)