A recent federal case involving a towing company may signal an initiative by federal agencies and prosecutors to use the Clean Water Act against vessel owners and operators, commercial and recreational, in novel ways.

A Federal appeals court, in U.S. vs. M/G Transport Services Inc., reinstated the convictions of an inland towing company, a company officer, and two boat captains for criminally violating the act. The defendants were convicted of dumping the ashes and wastes from burn barrels without obtaining a National Pollutant Discharge Elimination System (NPDES) permit, which is required for discharges of pollutants into navigable waters.It is surprising that the defendants were charged under the Clean Water Act rather than under the Act to Prevent Pollution from Ships (APPS), under which discharges of garbage into navigable waters is prohibited.

There are also other signs of an initiative involving the CWA. For instance, the Environmental Protection Agency recently indicated it is considering regulation of ballast-water discharges through NPDES permits to control the introduction of non-indigenous species, despite the fact that the U.S. Coast Guard currently regulates such discharges under separate statutory authority.

The consequences of enforcing CWA regulations requiring discharge permits for ships are severe because criminal charges can be brought under the act on negligence alone, and the administrative burdens are heavy.

In M/G Transport, the court assumed that ships could obtain NPDES permits. However, to date, the EPA and states have issued permits to vessels only in special cases such as seafood-processing ships. Requiring commercial and other vessels to obtain an NPDES permit from each jurisdiction through which they navigate imposes a tremendous burden on both vessel operators and the permitting agencies. There is a better way.

Under the EPA's regulations, no NPDES permit is required for any discharge incidental to the normal operation of a vessel. This exclusion does not apply to rubbish, trash, or garbage. Discharges of these types of pollutants are already prohibited under Coast Guard regulations implementing APPS.

But what discharges are incidental to the normal operation of a vessel? The phrase is not defined in the regulations, and no examples are given. The EPA recently provided some clues in regulations issued under the Uniform National Discharge Standards (UNDS) program.

In 1996, Congress amended the CWA to address incidental discharges from vessels of the armed forces. Incidental discharges, like those from other vessels, were excluded from the permitting requirements of the CWA, but were still subject to varying state regulation. Recognizing the burden this would impose, Congress directed the EPA and the Department of Defense to develop a program to exempt these discharges from state control. The first step was to identify discharges incidental to normal operation.

On May 10, the EPA and the defense department issued a final rule identifying 39 discharges as incidental to the normal operation of armed-forces vessels. Notably, discharges of clean and dirty ballast were considered incidental discharges.

The impact of this upon the EPA's ability to require NPDES permits for ballast-water discharges from commercial ships is unclear. But several conclusions can be drawn from the discharges identified, and from the rule's supporting documentation.

First, vessel waste streams may qualify as incidental to normal operations even though they are unique to a specific vessel or type of vessel (for example, compensated fuel ballast discharges). Second, a waste stream may be excluded even though it is related to a special function of the ship (for example, catapult-related waste streams from aircraft carriers). Third, the waste stream need not be associated with the propulsion or mechanical functioning of the ship (for example, water discharged from photographic laboratory drains).

The rule also indicates that incidental discharges can contain a variety of pollutants. The rule's supporting documents mentioned many different pollutants present in the discharges identified. Those pollutants included, among others, acids, cleaning agents, glycols, hydrazine, metals, nitrogen, paint and paint chips, residual chlorine, salts, solvents, and volatile and semi-volatile compounds.

Unfortunately, without regulations or guidelines, vessel operators who try to apply these principles run the risk that the EPA or the Department of Justice will disagree whether a particular discharge is incidental to normal operations.

Now that the groundwork has been laid under the UNDS regulations, the EPA should specify what discharges are considered incidental to the normal operation of non-military vessels to at least clarify federal requirements. While protection from state regulations requires additional legislation, the UNDS program shows that a national approach is possible.

As the M/G Transport decision indicates, the stakes for commercial and recreational vessel owners and operators are high, and they deserve clear guidance on this important issue.