Oyster Creek, the oldest of New Jersey's four nuclear power plants, will shut down Sept. 17, but some of its main buildings will remain standing for nearly six decades at the Ocean County site.

That's all new information contained in a report on the plant's decommissioning filed by Oyster Creek's owner, Exelon, with the federal Nuclear Regulatory Commission.

The company also said it had chosen a method that will span 60 years to complete the dismantling of the plant, versus beginning immediately.

Exelon had originally planned to shutter Oyster Creek in 2019 then, this past February, moved the date up to this October. That's now going to be mid-September at the end of the station's current fuel cycle, according to Suzanne D'Ambrosio, spokeswoman for Oyster Creek said Tuesday.

According to the report Exelon filed with the NRC, it has chosen to put the plant into long-term storage -- a method known as SAFSTOR -- and take advantage of the NRC's rules on decommissioning plants which allow a company up to 60 years to raze a facility.

"The SAFSTOR option is the most economical and radiologically safe plan for decommissioning," D'Ambrosio said. "It allows for normal radioactive decay, produces less waste and exposes our workers to lower levels of radiation."

Once it stops producing electricity Sept. 17, the process of moving the radioactive fuel from the reactor core to a spent fuel storage pool begins, something Exelon says should be done by Sept. 30.

In the coming years work will begin to remove some smaller buildings at the site, according to the report. The radioactive spent fuel rods will eventually be removed from the fuel pool and be placed in dry storage casks, a task Exelon says will be done by 2024.

The site will be maintained for 50-plus years until Exelon begins removing the larger components at the site beginning in June 2075 and wrapping up by December 2077, according to its report.

Some of the larger sections of the plant may actually be barged from near the site, according to the report.

The decommissioning is expected to cost the utility about $1.4 billion, Exelon says.

Environmentalists who have long been critical of the 620-megawatt plant, said they are glad to see it close.

"Oyster Creek has been a safety threat to Ocean County, polluting Barnegat Bay, and killing thousands of fish over the years," said Jeff Tittel, director of the New Jersey Sierra Club. "Shutting down the Oyster Creek plant will reduce the algae blooms, improve fish populations and help restore the overall ecosystem of the Barnegat Bay."

Claiming Oyster Creek was damaging the environment because it draws millions of gallons of water into the plant each day for cooling purposes, groups like the Sierra Club have long called for its closure.

Exelon Generation Announces Timeline for Retirement of Oyster Creek Generating Station https://t.co/jZUVYgRoQW pic.twitter.com/UYbf42HAAq — Exelon Generation (@ExelonGen) February 2, 2018

The plant had been granted a 20-year license extension by the NRC, but Exelon agreed to close the facility 10 years earlier if it would be allowed to operate without building cooling towers at the site.

"Since it doesn't have cooling towers, the plant has also been a major source of thermal pollution for the bay with their super-heated water causing severe algal blooms. When it comes to closing this plant we say, the sooner the better," Tittel said.

Tittel says the Sierra Club also takes exception with the decommissioning route Exelon has chosen for Oyster Creek.

"We believe that 60 years is way too long of a time to close the plant, especially given the increasing sea levels and storm surges. The plant could be hit by a storm worse than Sandy ..." said Tittel.

"The plant was only operating for 50 years and it doesn't make sense why it needs 60 years to take apart."

The Oyster Creek Generating Station in Ocean County is seen in this file photo. The plant will cease producing electricity on Sept. 17, its owner says. (File Photo)

Of the 24 nuclear power that have closed in the U.S., the operators of nine are opting for the extended SAFSTOR method while the 15 others have begun or plan to begin dismantling immediately, according to the NRC.

The NRC will hold a public meeting in the area of the plant in July on the report, according to Neil Sheehan, spokesman for the NRC.

The plant had employed about 500 workers. Recently, it was announced that 84 would be leaving through the fall.

"Approximately 400 Oyster Creek employees will remain onsite to shut down the facility," D'Ambrosio said. "Once the unit is shut down, a smaller workforce will remain at the site during decommissioning. The number of individuals needed at the site depends on the decommissioning milestones."

The plant which has operated since 1969, has an impact on the local community through both employment and other other economic spinoff. According to D'Ambrosio, Oyster Creek pays $2.5 million in property taxes and donates more than $250,000 in community donations through the United Way of Ocean County.

Oyster Creek is one of our nuclear plants in New Jersey. The other three, operated by PSEG Nuclear, are located at its Artificial Island generating complex in Lower Alloways Creek along the Delaware River.

Each of those three plants produce enough electricity to power about 1 million homes. Oyster Creek's electric output was enough to power about 600,000 homes, according to the company.

Bill Gallo Jr. may be reached at bgallo@njadvancemedia.com. Follow Bill Gallo Jr. on Twitter @bgallojr. Find NJ.com on Facebook. Have a tip? Tell us. nj.com/tips