Environmental groups were in court Monday in their attempt to block a controversial $225 million settlement the Christie administration reached with Exxon Mobil over widespread pollution at several refineries.

The settlement is far below the $9 billion the state originally asked for — and critics claim it is a giveaway to the company that is accused of dumping hundreds of chemicals around its plants and even pouring kerosene on wetlands to combat mosquitoes.

The environmental groups asked the state Appellate Division to overturn a Superior Court judge’s decision to deny them legal status to intervene in the case. If the Appellate Division agrees with the environmental groups, it will open the way for them to challenge the Christie-Exxon settlement.

The settlement, announced in February 2015, was for environmental damage to 1,800 acres of wetlands around Exxon’s refineries in Linden and Bayonne.

During oral arguments Monday in Trenton, Edward Lloyd, a Columbia Law School professor and environmental legal expert representing the advocacy groups, said the settlement amount “would not begin to compensate the public,” and that the extent of “contamination by Exxon was unprecedented.”

State Sen. Ray Lesniak, D-Union, whose district includes Linden and who has joined with the environmentalists to try to block the settlement, told the court that by agreeing to such a low settlement, the state Department of Environmental Protection “violated its duty to protect the interests of the public.”

Allan Kanner, a New Orleans lawyer hired by the state to represent the DEP, countered that the settlement was the largest ever in the country for a chronically polluted site.

He said the settlement provided more value to the state than the money alone. “We thought we could leverage this settlement,” he said. He noted that it locked in a number of rulings made during the case that would strengthen the DEP's legal hand in future natural resource damage cases.

Kanner and Theodore Wells Jr., Exxon's lawyer for the case, argued that the environmental groups have no legal standing after 12 years to enter the case now.

The delay caused by the environmental groups' bid to block the settlement “has been terrible for the state,” Kanner argued. He said the money could have been used by now to help with cleanup and restoration efforts.

The appellate court likely won’t hand down a decision for a month or more. Whichever side loses could then appeal to the state Supreme Court. The $225 million settlement does not involve costs Exxon must incur related to ongoing cleanup of the contamination.

The environmental groups involved include the New Jersey Sierra Club, Clean Water Action, Delaware Riverkeeper and Environment New Jersey.

Even though it was the largest environmental damage settlement in state history, critics were outraged that Christie had secured so little from Exxon. In the state's original bid for $9 billion, a judge had already ruled that Exxon was liable for damages from decades of pollution at the refineries. Superior Court Judge Michael Hogan was just about to rule on how much Exxon should actually pay when Christie announced the settlement.

Critics were also upset that the deal included 16 smaller sites, such as a fuel farm at Teterboro Airport, as well as 1,800 retail gas stations that were not part of the original case.

When the state's environmental lawsuit against Exxon was filed in 2004, the state argued in court documents about “gross and pervasive contamination” by Exxon. It described extensive damage to wetlands, marshes, meadows and waters from the discharge of more than 600 hazardous chemicals. The state accused Exxon of pouring kerosene on wetlands at two of its former refineries in New Jersey to control mosquitoes and noted that an expert retained by the oil giant “described nature as the ‘enemy’ and something to be ‘conquered.’ ”

“The scope of the environmental damage ... is as obvious as it is staggering and unprecedented in New Jersey,” the state said in one of its court documents. It described “millions of gallons of free product floating on groundwater” and “millions of cubic yards of hazardous waste sitting on top of former wetlands.”

Exxon, the state declared, had used wetlands “as waste receptacles.”

Lawyers for Exxon, meanwhile, wrote scathingly of the DEP’s arguments. The company said the state’s “evidence does not support the enormous award it seeks,” and that the state's arguments “ignore the evidence, science and the law.”

It said such a huge reward “would be untethered to any proof of actual injury or harm.”

After the settlement was reached, the Christie administration argued it was hampered from securing a larger payment. For starters, the previous administration of Gov. Jon Corzine had already put on the table in 2008 a $550 million settlement, which Exxon rejected, the Christie administration said. In addition, the state had suffered two defeats in similar suits, making a settlement seem more appealing. Those cases — against Union Carbide and Essex Chemical — also involved damages to natural resources and were thrown out by a judge, weakening the state’s position on such cases, the administration said.

Lloyd, representing the environmental groups, argued before the court Monday that the risk those cases reflected in letting a judge determine what Exxon should pay “do not justify a 97 percent discount” for Exxon by settling with the company for so little. He noted that the risks were not that significant, since the DEP had won many challenges by Exxon through the course of the trial that found the company liable.

Kanner, speaking for the DEP, painted a different picture of the risks and defended the state's decision to settle. “The state had tried two cases and lost both of them, and that hurt our forward momentum” on natural resource damage cases, Kanner told the court. The DEP thought the Exxon settlement “was a chance to regain momentum.”

In August 2015, Hogan approved the Exxon settlement, writing that the deal was “fair, reasonable, in the public interest, and consistent with the goals of the Spill Compensation and Control Act,” the law under which the state had originally sued Exxon.

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