The Environment Protection Agency (EPA) of the USA issued its most recent Vessels General Permit, under the National Pollutant Discharge Elimination System (NPDES), a Clean Water Act (CWA) program, in 2013. The permit applies to large commercial vessels (79 feet (24 m) in length or greater) (except fishing vessels) and regulates 26 specific types of vessel discharges:

Deck Washdown and Runoff and Above Water Line Hull Cleaning
Bilge water/Oily Water Separator Effluent
Ballast water
Anti-fouling Hull Coatings/Hull Coating Leachate
Aqueous film forming foam (AFFF)
Boiler/Economizer Blowdown
Cathodic protection
Chain Locker Effluent
Controllable Pitch Propeller and Thruster Hydraulic Fluid and other Oil Sea Interfaces including Lubrication Discharges from Paddle Wheel Propulsion, Stern Tubes, Thruster Bearings, Stabilizers, Rudder Bearings, Azimuth Thrusters, and Propulsion Pod Lubrication, and Wire Rope and Mechanica l #Equipment Subject to Immersion]
Distillation and Reverse Osmosis Brine
Elevator Pit Effluent
Firemain Systems
Freshwater Layup
Gas Turbine Washwater
Graywater (except certain commercial vessels operating in the Great Lakes)
Motor Gasoline and Compensating Discharge
Non-Oily Machinery Wastewater
Refrigeration and Air Condensate Discharge
Seawater Cooling Overboard Discharge (Including Non-Contact Engine Cooling Water; Hydraulic System Cooling Water, Refrigeration Cooling Water)
Seawater Piping Biofouling Prevention
Boat Engine Wet Exhaust
Sonar Dome Discharge
Underwater Ship Husbandry
Welldeck Discharges
Graywater Mixed with Sewage from Vessels
Exhaust Gas Scrubber Washwater Discharge.[5]
Approximately 69,000 vessels, both domestic and foreign flagged, are covered by the VGP.