Exelon expects to spend nearly $1.5 billion over more than six decades for decommissioning, spent fuel management, and site restoration of its soon-to-close Oyster Creek Nuclear Generating Station in New Jersey.
The power company’s Exelon Generation subsidiary will close the single-reactor power plant by Oct. 31 of this year – more than a year earlier than required by an agreement with the state and over a decade before its Nuclear Regulatory Commission operating license expires in 2029.
In the mandatory post-shutdown decommissioning activities report (PSDAR) to the NRC, Exelon Generation said it has selected the SAFSTOR (safe storage) approach for decommissioning. That allows a defueled reactor site to remain intact under monitoring for up to six decades while radioactivity levels drop and the owner builds up its fund to pay for decommissioning.
Exelon said it could not respond by deadline Friday to a request for comment on its reasoning for choosing SAFSTOR.
“The selection of a preferred decommissioning alternative is influenced by a number of factors at the time of plant shutdown,” the PSDAR states. “These factors include the cost of each decommissioning alternative, minimization of occupational radiation exposure, availability of a high-level waste (spent fuel) repository or a Department of Energy (DOE) interim storage facility, regulatory requirements, and public concerns. In addition, 10 CFR 50.82(a)(3) requires decommissioning to be completed within 60 years of permanent cessation of operations.”
In Exelon’s decommissioning schedule, the plant shutdown and defueling outage would begin on Sept. 17 and end by Sept. 30. All fuel would be in wet storage for cooling no later than March 19, 2020, and then transferred to dry storage within four years.
The plant would then be dormant until early December 2073, during which limited operations would continue, including security, maintenance, and radiation monitoring.
Preparations for decommissioning would take about a year-and-a-half. Actual operations would begin in June 2075, starting with large component removal, then systems removal and plant decontamination, and finally license termination by September 2078. Site restoration would stretch to April 2080, after which the property would be cleared and available for other use.
Exelon expects to spend just over $1.1 billion on decommissioning, along with $290 million on spent fuel management and $60 million on site restoration. It has two separate trusts to pay for the work: a non-tax qualified fund that held $68.2 million as of Dec. 31, 2017, and a tax-qualified fund that had $913.9 million at that date.
Spent fuel is likely to remain on-site until September 2034, according to the PSDAR. That is the point at which Exelon believes the Energy Department would presumably meet its legal mandate to take the radioactive material from Oyster Creek (and all other U.S. nuclear power plants) for disposal.
“Exelon currently assumes that remaining structures will be removed to a nominal depth of three feet below the surrounding grade level,” the PSDAR says. “Affected area(s) would then be backfilled with suitable fill materials, graded, and appropriate erosion controls established. Non-contaminated concrete remaining after the demolition activities may be used for backfilling subsurface voids or may be transported to an offsite area for appropriate disposal as construction debris.”
