New Jersey lawmakers plan a hearing and a lawsuit over a settlement that the Christie administration has reportedly reached with ExxonMobil Corp. in a years-long legal battle over the company's discharge of hazardous materials onto 1,500 acres of state land.

Lawmakers said the Senate would sue to block the settlement - which the New York Times, citing anonymous sources, reported last week was for $250 million. The state previously sought billions for restoration and damages.

"If what's been reported is accurate, then this is an egregiously irresponsible decision that raises many, many questions and concerns," Assembly Speaker Vincent Prieto (D., Hudson) said in a statement Wednesday.

The Assembly Judiciary Committee will hold a hearing on the matter March 19, Prieto said.

A Christie administration official said any settlement would be a penalty separate from environmental cleanup and remediation costs imposed on ExxonMobil. The official characterized the settlement as "a fine on top of the cost of the cleanup."

The case stems from a 2004 lawsuit filed by the state Department of Environmental Protection against ExxonMobil under the New Jersey Spill Operation and Control Act.

The state alleged that for decades, ExxonMobil's plants and refineries in Bayonne and Linden discharged hazardous substances that affected groundwater, surface water, and wetlands.

The case went to trial last year. All that was left for the judge to determine was what ExxonMobil owed in damages.

But the Times reported that the state recently asked the judge to delay ruling on the case to allow settlement talks to proceed.

Spokesmen for ExxonMobil and the Attorney General's Office declined to comment.

The settlement requires public comment and approval from the DEP.

Language in the appropriations act signed by Christie in June for fiscal 2015 says the state must deposit the first $50 million "in natural resource, cost recoveries and other associated damages" into a fund for hazardous discharge cleanup.

The law says any additional money obtained through such litigation shall be diverted to the general fund as revenue. Jeff Tittel, director of the New Jersey Sierra Club, said that provision was unprecedented and allows Christie to give away "the biggest corporate subsidy in state history."

Democrats, who control the Legislature, had sought to ensure that 50 percent of such money - beyond the initial $50 million - would be dedicated to environmental cleanup. Christie, a Republican, vetoed that language from the budget bill.

On Tuesday, Senate President Stephen Sweeney (D., Gloucester) and Sen. Raymond J. Lesniak (D., Union) said the Senate would preemptively file a lawsuit to block the settlement.

"When we learned that the administration planned to accept the equivalent of three cents on the dollar for the extensive damage to the environment, we decided to intervene to stop them and to protect the state's interests," Sweeney said in a statement.