The amount illegally discharged is small compared with the 1.8 billion gallons of sewage the city's 14 plants treat each day.

But the US authorities, in particular, have prosecuted and fined cruise companies for illegally discharging waste into its waters.

"We estimate that there are about 40 sewage-treatment plants that are illegally discharging sewage into the Sound," he said.

This fall it filed two new lawsuits against city high schools for illegally discharging struggling students.

After the new procedures were in effect, the group filed lawsuits this fall against two more high schools, charging that they, too, were illegally discharging students.

It illegally discharges millions of gallons a day of toxic liquid, leached from the trash, into the Arthur Kill.

Environmentalists have identified 60 similar sites where Pemex has been illegally discharging petroleum wastes in that area, Mr. Calvillo said.

Boaters can and will be prosecuted if they illegally discharge wastes.

The company was indicted by a Federal grand jury here in January on 78 counts of illegally discharging pollutants.

Alleged violations include: Illegally discharging a hazardous material into the waters of the United States.