But the coalition charged today that the standards the environmental agency adopted under the agreement could undercut the two-year-old ban on use of the site - widely known as the Mud Dump - for toxic or contaminated muck.

The worms' tissue contained 170 parts per billion of PCB's, about the same level of PCB's that exist now at the Mud Dump.

Ms. Zipf and others argued that the current standards for PCB's and P.A.H.'s and the Castle Astoria dredge material would increase pollution at the Mud Dump.

Cap's a Question, Too Besides concerns about dioxin's absorption in fish tissue, ecologists are also troubled by how the Mud Dump would be capped, and when.

The mud buoy marks the site of the 2.2 square-mile Mud Dump ( officially, the New York Bight Dredged Material Disposal Site. )

The Mud Dump is also running out of room, said Peter Shugert, a spokesman for the corps.

Even some other environmentalists believe that Clean Ocean Action is demanding impossible purity in what is used for the protective cover of the Mud Dump.

While some environmental groups said they were pleased that the Mud Dump might eventually be closed to toxic material, they said regulators should not latch on to the idea of a containment island as a panacea.

The sediment was to be deposited in what is called the Mud Dump, a federally regulated site off Sandy Hook.

But last week, the Federal Environmental Protection Agency barred the use of the Mud Dump after tests determined that the Howland Hook sediments fall into category 3, the highest level of toxicity.