The Army Corps of Engineers will convene an important public hearing next week in New Jersey. People in the New York-New Jersey port community, both business and labor, should take pains to be there. So should people from the broader business and labor sectors in the region. So, in fact, should anyone who values the port.

They should attend not to debate the hard-core port opponents who demanded the hearing, scheduled Monday at Fort Monmouth, N.J., but to go beyond them. Key lawmakers will be watching closely to see if this issue has more than one side. If port opponents are the only ones there, many will conclude it doesn't and act accordingly.In other words, if port proponents fail to show up and speak out, they will be taking a long step toward ceding control over the port's future to a radical, single-issue group that has worked against them for years. The impact will be negative for the maritime business and for the region's manufacturers, retailers, consumers and for the environment.

But the people who don't speak out will have no one to blame but themselves.

At the heart of the matter once again is dredging. That may strike some as odd; the New York-New Jersey port's long-running dredging crisis was supposed to have been resolved three-and-a-half years ago in a compromise agreement brokered by Vice President Al Gore. But the group that that negotiated the Gore plan with the administration and the port - Clean Ocean Action, the same group that created the crisis in the early 1990s - has reneged on the agreement and is back to its old tricks.

The specific issue at hand is whether mud from two projects in New York City - routine maintenance dredging at the Castle Astoria tanker terminal in Queens and at the Brooklyn Marine Terminal - should go to the Historic Area Remediation Site, formerly known as the Mud Dump, about six miles off the New Jersey coast.

The Gore agreement closed the Mud Dump, which had been used for ocean disposal for most of the 20th century, in 1997; the closure had been a prime goal of Clean Ocean Action. However, the agreement also permits clean dredged material - so-called Category I material - to be placed at the site to cap contamination caused by unregulated disposal years ago.

After extensive tests, the Corps of Engineers and the Environmental Protection Agency agreed that the material from both projects met the standards for placement at the ocean site. The Brooklyn permit was issued Nov. 29, and the first dredging work was completed last month. The Castle-Astoria permit was issued Jan. 11, nearly three years after it was requested; because of restrictions during fish-spawning season, its work is unlikely to begin until the fall.

The activists had focused their efforts on defeating the Castle-Astoria permit. They apparently missed the boat on the Brooklyn permit. The government says it sent out nearly 400 copies of the public notice on the project, and also sent testing data to Clean Ocean Action. There was little response during the 30-day public-comment period. However, New Jersey lawmakers squawked after the permit was issued that they had not been among the recipients of the public notice - and a red-faced corps admitted it had blundered. As a result, Monday's public hearing was scheduled.

The bottom line is that, now that its objective of shutting down the Mud Dump has been achieved, Clean Ocean Action doesn't want to abide by the rest of the Gore agreement. It doesn't want to be bound by standards dictated by an agreement it negotiated with the Clinton administration and the port. It wants to set the standards. And it will use its considerable legal and public-relations skills to win that power.

The group, as it did several years ago when it launched the dredging crisis, is masterfully mixing dire predictions, pseudo-science and a misleading smattering of facts into a successful campaign to scare the dickens out of the public on the Jersey Shore. It's depicting the use of the Historic Area Remediation Site as environmental Armageddon; New York, it says, is dumping deadly toxic waste on New Jersey's beaches, just as it dumped medical waste on sewage on Jersey beaches in the 1980s.

The truth is that the mud in question is not toxic waste, is not going near the beaches and cannot reach them, is not being dumped by New York and has no connection to the 1980s incidents.

But people on the Jersey shore aren't getting that word. And some of the lawmakers don't want to hear it. Some are angry that New York hasn't made progress finding upland disposal alternatives, as New Jersey has. Others just see an opportunity to play to an emotional crowd on an issue they think has only one side.

There is, however, another side. That, very simply, is that the port is an integral part of both the region's economy and its environment. It serves as an efficient gateway for consumer goods and the region's exports. It generates tens of thousands of well-paying jobs. It helps keep the region's economy thriving - and able to support environmental programs. If it didn't exist, goods would be moved through other, more distant seaports and trucked long distances to the region, raising costs and addding hundreds of thousands of additional truck trips to an already congested highway system.

But to do its job - to handle modern ships - the port has to be dredged and re-dredged regularly. And dredging can't take place unless there is an efficient, sensible way to deal with the material that's dredged up.

People who value the port should show up at Fort Monmouth Monday to explain that to the hearing officers and the lawmakers who'll be watching. They should also take a lesson from the activist group's letter and e-mail campaigns to politicians and public officials.

People in other ports should follow suit; they're next if the activist group succeeds in New York-New Jersey.

If port supporters don't speak out now, their side will be ignored and forgotten - and it really will be a one-sided issue.