Reportable discharge of oil (40 CFR 110.3)

Harmful quantities of oil discharged or released to navigable waters of the United States are any amount that violates State water quality standards and/or causes a sheen or film (as little as 10 parts per million of oil can cause a sheen), upon or discoloration of the surface of the water or adjoining shorelines or cause a sludge or emulsion to be deposited beneath the surface of the water or upon adjoining shorelines. An exception is a sheen caused by outboard motors.