After over 49 years in service the single unit  Oyster Creek Generating Station in New Jersey, the oldest US commercial nuclear plant, was powered down on 17 September.

The retirement of Oyster Creek, a 619 MWe General Electric boiling water reactor, makes it the seventh US reactor to close in the past five years.

“It’s not safety. It’s not reliability. It’s the market and federal policies that don’t recognise the value that nuclear energy provides to this country,” said Bryan Hanson, chief nuclear officer of operating company Exelon.

In May, the US Energy Information Administration reported that 15% of nuclear plants in the USA are planned to close by 2025, with more closures expected to be announced.

Exelon agreed to sell Oyster Creek, the property and its nearly $1 billion decommissioning trust fund, to Holtec International. Holtec will take over the process of decommissioning the plant and restoring it for future development, a process that Exelon has estimated will cost more than $1.4 billion. Exelon had planned on a 75-year decommissioning process, during which the site would remain under care and maintenance until radiation levels returned to normal. However, Holtec has proposed a rapid eight-year decommissioning plan. The sale, which requires both federal and state approval, will not be completed until late 2019.

Oyster Creek was previously expected to retire on in December 2019, but it was retired a year early to coincide with the plant’s fuel and maintenance cycle. The plant’s initial 40-year licence expired in 2009, but although the Nuclear Regulatory Commission granted a 20-year licence renewal, in 2010 an agreement was reached between Exelon and New Jersey state environmental regulators to close the plant in 2019. The decision was based on local water safety concerns and estimated costs of more than $800m to install cooling towers to meet new environmental standards.  Exelon said Oyster Creek alone represents 15% of the state’s total installed nuclear capacity and about 7% of total electricity production.