In this subtitle, the following terms have the meanings indicated. “Free-floating oil” means oil that can be removed in adequate facilities for gravity separation. “Slug” means any discharge of significant quantities of water, sewage, or industrial waste which, in concentration of any given constituent or quantity of flow, could:cause interference of the treatment works; pass-through the POTW; endanger sewer worker safety; contaminate the sludge; or cause a violation of any permit issued to the treatment plant. City Code, 1976/83, art. 25, §1(h), (dd) Ord. 75-914 Ord. 84-129 Ord. 91-775