The Oyster Creek nuclear reactor in New Jersey will be shut down by 2019, at least 10 years before its license expires, in a deal with state environmental regulators that will allow it to operate until then without building costly cooling towers, its owner said on Wednesday.

Exelon Nuclear, which owns the reactor, in Lacey Township in Ocean County, has been negotiating with Gov. Chris Christie on the issue since he took office this year, said Exelon’s chief nuclear officer, Christopher M. Crane.

Installing cooling towers “would cost us significantly more than the current value of the plant,” Mr. Crane said in a telephone interview. Under Gov. Jon S. Corzine, the previous state administration had approved a draft environmental permit for the plant that would have required cooling towers so the plant would stop pumping hot water into Barnegat Bay.

The plant, the oldest operating power reactor in the United States, was built in 1969 by Jersey Central Power and Light Company. Exelon and a partner each bought a 50 percent share in 2000, and Exelon bought the partner out in 2002.