A half-century has passed since workers at Diamond Shamrock were ordered to dump dioxin into the Passaic River in Newark, and then to march out at low tide and knock down the toxic mud piles with rakes so that no one would know.

So began the long history of polluters evading responsibility for the murder of this river, an effort that continues to this day. Workers with rakes have been replaced by consultants and lawyers.

And as polluters clean up their messes in places like the Hudson River and the Great Lakes, the Passaic remains an industrial dead zone, where fishing and swimming are off limits, and even boats are a rarity.

With each tide, year after year, the dioxin sloshes up and down the river and into Newark Bay. It poisons the worms and crabs that crawl through the tainted muck, and then poisons the birds and fish that eat them.

“When I grew up here, we just never went near it, and I lived three blocks away,” says Ana Baptista of Newark’s Ironbound community. “It was far off limits, so dirty you wouldn’t even touch it. And there was no way to get down close to it. It was like the ugly stepsister of the Hudson.”

If that makes you furious, it should. Because this river is owned by the public, and it could be an ornament to this region of the state.

It could be lined with parks, with pleasure boats tied up at wooden docks. It could be a place where couples get dinner and go for a stroll, where kids fly kites and eat ice cream, where people would pay extra for the privilege of living in a small apartment nearby. That’s all happening in other cities.

“The people of New Jersey were deprived of a valuable resource,” says Alan Steinberg, the regional director of the Environmental Protection Agency under President George W. Bush. “The damage has been terrible, and it has to be remedied. What I’d hope is that (the polluters) get a sense of reality and realize they can run but they can’t hide. Eventually they will be made to pay.”

So far, though, the polluters have agreed only to clean hot spots in two locations. And the Obama and Christie administrations say that simply will not do.

The Passaic, they say, needs to be dredged from one bank to the other, for the lower eight miles at least, and capped with two feet of coarse sand.

The cost could rise to a staggering $3.5 billion. And that’s why the high-priced consultants and lawyers have spent years doing all they can to delay and shrink the cleanup.

So far, the polluters are winning and the river is losing. But another showdown looms later this year, when the EPA is expected to issue its definitive cleanup plan. Even then, dredging wouldn’t begin until 2018, after public comment, revisions and engineering work.

“The credibility of the EPA’s ability to handle these big river cleanups is at stake,” says Lisa Jackson, the recently departed head of the EPA. “It’s disappointing and really frustrating to know that this many years have gone by.”

DIRTY DEEDS

Diamond Shamrock and its corporate successors are the lead villains in this story. The Newark factory, which produced Agent Orange, is now a giant concrete bunker on the western bank of the river.

The company knew even in the 1950s that dumping dioxin was illegal, and set up an alarm system to warn employees when inspectors were sniffing around. If there is a hell, then it’s made for people like this.

But dioxin is not the only problem in the Passaic. The EPA has identified dozens of companies that contributed to the river’s woes, and several public sewer systems.

That presented a golden opportunity for delay, because there is a valid argument about who should pay what share of the cleanup. So Diamond Shamrock’s successors filed suit to drag in the other polluters.

This takes a page from the fabled Roman senators who murdered Julius Caesar. Because each senator plunged in the knife, the hope was that it would be impossible to know which wound killed the tyrant.

That won’t work in the end, because no one disputes that dioxin is the key issue in the Passaic. It was Diamond Shamrock that killed this river. And if the companies don’t agree to cost-sharing, the law allows the EPA to do the work itself and collect triple damages from the polluters. It’s unlikely they will risk that.

For now, though, the polluters are split into two camps. Diamond Shamrock’s successor corporations are in one, and are mostly defiant. The others have formed a coalition known as the Cooperating Parties Group and have been more forthcoming.

Still, the CPG is pushing aggressively to scale back the cleanup plan and reduce its costs. It has been meeting with community groups and local politicians, persuading some to write letters to the EPA urging the agency to back off.

In these same meetings, the CPG has offered to fund local projects as a sweetener. And this being Jersey, the money has been persuasive. One letter came from Hudson County, which got $50,000 for open space. Another came from Sen. Paul Sarlo (D-Bergen), whose towns got $175,000 in grants.

The CPG has hired experts to pitch a smaller cleanup focused on hot spots. They want the EPA to delay the release of its dredging plan until the CPG alternative is ready in 2015. And they are trying to sow regional divisions by claiming that the EPA’s plan will worsen pollution in its upper reaches by stirring up pollutants.

That is all self-serving nonsense, according to federal and state regulators. The Obama and Christie administrations agree that bank-to-bank dredging is the only adequate answer. So did the administrations of Jon Corzine and George W. Bush.

“We are in lockstep agreement with the EPA on that,” says Bob Martin, commissioner of the state Department of Environmental Protection. “Cleaning just hot spots is absolutely not adequate and not acceptable. This is the most contaminated site with dioxins anywhere in the world.”

LIVING PROOF

Look to the Hudson for proof that dead rivers can indeed come back to life. You have to remove the industrial pollutants, treat the sewage and control the runoff.

But communities along the Hudson got their river back. Fish species that had disappeared are back in abundance. Kids are swimming again. Green parks line the river banks. Restaurants and apartments have sprung up everywhere.

Baptista works with the Ironbound Community Corporation, which pushed the city and county governments to save some parkland along the Passaic in Newark. It’s a start. But she sees a day when the riverfront will be thriving, once the toxins are gone.

“My greatest wish is that we don’t have another generation growing up not being able to appreciate the river,” she says. “That’s really from the heart.”

Tom Moran may be reached at tmoran@starledger.com or (973) 392-5728.

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