<P> Concurrently, litigation regarding the National Pollutant Discharge Elimination System (NPDES) permit program led to a 2008 decision by the Ninth Circuit Court, ruling that EPA could not exclude vessel discharges from NPDES requirements . Subsequently EPA issued an initial Vessel General Permit (VGP) with an effective date of February 6, 2009 . </P> <P> Cruise ships generate a number of waste streams that can result in discharges to the marine environment, including sewage, graywater, hazardous wastes, oily bilge water, ballast water, and solid waste . They also emit air pollutants to the air and water . These wastes, if not properly treated and disposed of, can be a significant source of pathogens, nutrients, and toxic substances with the potential to threaten human health and damage aquatic life . Cruise ships represent a small--although highly visible--portion of the entire international shipping industry, and the waste streams described here are not unique to cruise ships . However, particular types of wastes, such as sewage, graywater, and solid waste, may be of greater concern for cruise ships relative to other seagoing vessels, because of the large numbers of passengers and crew that cruise ships carry and the large volumes of wastes that they produce . Further, because cruise ships tend to concentrate their activities in specific coastal areas and visit the same ports repeatedly (especially Florida, California, New York City, Galveston, Seattle, and the waters of Alaska), their cumulative impact on a local scale could be significant, as can impacts of individual large - volume releases (either accidental or intentional). </P> <P> MARPOL 73 / 78 is one of the most important treaties regulating pollution from ships . Six Annexes of the Convention cover the various sources of pollution from ships and provide an overarching framework for international objectives . In the U.S., the Convention is implemented through the Act to Prevent Pollution from Ships . Under the provisions of the Convention, the United States can take direct enforcement action under U.S. laws against foreign - flagged ships when pollution discharge incidents occur within U.S. jurisdiction . When incidents occur outside U.S. jurisdiction or jurisdiction cannot be determined, the United States refers cases to flag states, in accordance with MARPOL . These procedures require substantial coordination between the Coast Guard, the State Department, and other flag states, and the response rate from flag states has been poor . </P> <P> In the United States, several federal agencies have some jurisdiction over cruise ships in U.S. waters, but no one agency is responsible for or coordinates all of the relevant government functions . The U.S. Coast Guard and EPA have principal regulatory and standard - setting responsibilities . </P>

What happens to the garbage on a cruise ship