EPA's Vessel General Permit and Small Vessel General

For vessels covered under the VGP, EPA requires vessel owners/operators to minimize the
amount of disinfection or biocidal agents used in freshwater layup (i.e., the minimum required to
prevent aquatic growth).
Gas Turbine Washwater. Gas turbines must be cleaned to remove materials such as salts and
spent lubricants. These materials may be discharged into waters of the U.S. and may also
include cleaning agents.
For vessels covered under the VGP, EPA prohibits the direct discharge of gas turbine washwater
within waters of the U.S. They require vessel owners/operators to prevent commingling of gas
turbine washwater and bilgewater, where feasible. They prohibit the discharge of oils, including
oily mixtures, from gas turbine washwater in quantities that may be harmful as determined in
accordance with 40 CFR Part 110.
Graywater. Graywater is water that has been used for bathing, in sinks, laundry etc., and may
contain pathogens, nutrients, soaps, detergents, and other organic pollutants. Some –usually
large– vessels collect and store graywater for later treatment and discharge. Other vessels
discharge untreated graywater directly into waters of the U.S.
For vessels covered under the VGP, EPA requires vessel owners/operators to minimize the
discharge of graywater while in port. For those vessels that cannot store graywater, the owner or
operator and their crews are required to minimize the production of graywater in port. Examples
of ways to minimize production of graywater include delaying laundry, scullery activities, and
restricting length of showers while in port, and using high efficiency faucets and showerheads.
Vessel owner/operators are required to minimize the discharge of graywater when the vessel is
not underway. Vessels that have the capacity to store graywater are prohibited from discharging
graywater in federally protected waters listed in Appendix G of the VGP. For vessels that cannot
store graywater, vessel operators must minimize the production of graywater while in those
waters. For vessels greater than 400 gross tons that regularly travel more than 1 nm from shore
and have the capacity to store graywater for a sufficient period, treated graywater must be
discharged greater than 1 nm from shore while the vessel is underway, unless the vessel meets
the following treatment standards and requirements:
� The discharge must satisfy the minimum level of effluent quality specified in 40 CFR §
133.102;
� The geometric mean of the samples from the discharge during any 30-day period may not
exceed 20 fecal coliform/100 milliliters (ml) and not more than 10 percent of the samples
exceed 40 fecal coliform/100 ml; and
� Concentrations of total residual chlorine may not exceed 10.0 micrograms per liter (μg/l).
For vessels that do not travel more than 1 nm from shore, EPA requires vessel owners/operators
to minimize the discharge of graywater and, provided the vessel has available graywater storage
capacity, and dispose of graywater onshore, if appropriate facilities are available and such
disposal is economically practicable and achievable, unless the vessel meets aboved listed
treatment standards and requirements. The vessel owners/operators are required to minimize the
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