WASHINGTON -- The Army will not be allowed to dump the byproduct of a neutralized nerve agent in the Delaware River until more study of the contentious plan is completed.

A broad military spending bill President Bush signed into law Wednesday included the provision inserted by New Jersey congressmen to keep the byproduct of neutralized VX from being shipped from Indiana to New Jersey for disposal.

Under the new law, the Government Accountability Office must review studies of the plan before the VX byproduct can be taken to New Jersey. That likely delays the dumping until at least February.

VX is so deadly that a single drop can kill. The Army is required by a 1997 international treaty to destroy the chemical weapon by 2012 and is neutralizing it at the Newport Chemical Depot in western Indiana.

For years, the Army has tried to win approval to ship the byproduct to a DuPont facility in Deepwater, N.J., where it would be treated and discharged into the Delaware River.

Environmentalists and officials in Delaware and New Jersey oppose that plan and have said they will fight it through legislation and in the courts, if necessary.

"I do not think there is any answer that can be given to satisfy our concerns," U.S. Rep. Frank LoBiondo, R-N.J., said Thursday.