Which discharges have special requirements under the U.S. VGP?

• A. Ballast water discharges
• B. Bilge and greywater discharges
• C. Waste oil discharges
• D. Sewage discharges

Answer: (B)

The main idea here is that while many vessel discharges are governed by general permit limits, some specific discharge types carry higher pollution risks and thus have extra requirements. Bilge water and greywater fall into that category because they routinely carry substances that can seriously affect water quality: bilge water can contain oil, fuel, solvents, and other hydrocarbons from machinery spaces, and greywater includes wash water with detergents, food residues, and other organic pollutants. To prevent these pollutants from entering the water, the U.S. VGP requires additional controls beyond the standard limits—typically requiring proper treatment (such as oil–water separation for bilge water and treatment or retention for greywater) and ensuring any discharge meets stricter standards before release. This is why these two discharges have special requirements under the VGP.