Discharges to Water: Notes
Oil, petrol/gasoline, solvent, acids, hydraulic oil, antifreeze, and other such substances should never be poured down a drain and every precaution must be taken to prevent spillage reaching drains.
Handling of such materials must take place well away from drains, and preferably in an area with a curb or wall around it to prevent discharge into a drain. If a spillage occurs, it should be soaked up immediately. Having a spill kit readily available will make this easier.