Citing concerns about public health, public safety and financial risks, Attorney General Maura Healey and Energy and Environmental Affairs Secretary Matthew Beaton have asked federal nuclear regulators to allow the state to intervene in the federal review of the proposed sale and license transfer of Pilgrim Nuclear Power Station in Plymouth.

In the petition filed Thursday, Healey and Beaton argue that current owner Entergy Corp. and proposed new owner Holtec International have not demonstrated that the plant's Decommissioning Trust Fund has a balance adequate to cover all the costs associated with decommissioning the plant and the long-term managing of spent fuel, which could lead to health and safety problems.

Healey and Beaton are asking that the Nuclear Regulatory Commission schedule an adjudicatory hearing on the sale of the plant, which is slated to close for good by June 1, and the state's concerns.

Entergy, which bought Pilgrim from Boston Edison in 1999, is seeking to sell the plant to Holtec, a company that specializes in "accelerated decommissioning" of power plants. The companies filed a joint license transfer application in November asking the NRC to approve the sale by the time the power plant closes by June 1. Each company has submitted its own decommissioning activities plan.

"This proposed deal puts the health and safety of our residents at risk," Healey said in a statement. "We're intervening to protect the public and ensure that the transaction does not leave our state's taxpayers on the hook for any of the costs of safely decommissioning the plant, restoring the site, and managing spent nuclear fuel."

If the sale and license transfer applications are approved, Holtec plans to transfer fuel from Pilgrim between 2019 and 2021 and restore the site to meet NRC requirements by 2027. Activity would continue at the spent fuel storage installation until 2062 or 2063, and the Pilgrim site would be fully restored by 2064, according to the company's filings.

"The decommissioning of the Pilgrim Nuclear Power Station must be completed in a manner that protects the safety of the public and environment, without undue financial burdens," Beaton said in a statement. "Intervening in the federal process gives voice to the concerns raised by the Commonwealth's residents and will help ensure that these concerns are considered during the license transfer proceeding."

NRC spokesman Neil Sheehan said Thursday that the agency's review of the license transfer application is ongoing and that the "adequacy of the decommissioning trust fund is one of the areas the staff is evaluating."

He said that Healey and Beaton's request for a hearing is also under review and "it would be premature to say if a hearing would be granted or if so, whether any decisions stemming from that proceeding could impact the staff's review" of the sale and license transfer.

The plant, which began generating power in 1972, employs about 600 people and generates 680 megawatts of electricity. It is slated to be removed from service by June 1.