The Nuclear Regulatory Commission (NRC) said Aug. 1 that it has issued a Safety Evaluation Report (SER) with Open Items on the license renewal application for the Limerick Units 1 and 2 in Limerick, Pa.
The open items concern operating experience for aging-management programs and corrosion of the steel liner of the suppression pools and their internal pipes, called “downcomers,” the agency noted. A boiling water reactor’s suppression pool is a large reservoir of water beneath the reactor designed to cool steam rapidly in the event of a loss-of-coolant accident.
Exelon Generation Co. LLC, a unit of Exelon (NYSE: EXC), submitted an application to the NRC in June 2011 to extend the Limerick operating licenses by 20 years. The current 40-year operating licenses expire on Oct. 26, 2024, for Unit 1 and June 22, 2029, for Unit 2.
The SER issued by the agency documents the results of the NRC staff’s review of the license renewal application and site audit of Limerick’s aging-management programs to address the safety of plant operations during the period of extended operation.
“Overall, the results show that Exelon has identified actions that have been or will be taken to manage the effects of aging in the appropriate systems, structures and components of the plant, and that their functions will be maintained during the period of extended operation,” the commission noted. “After Exelon provides satisfactory information to resolve the open items, the NRC staff will present its final conclusions on the license renewal application in an update to this SER.”
The NRC staff is finalizing a draft Supplemental Environmental Impact Statement on the Limerick license renewal. The SER and the license renewal application have also been provided to the NRC’s Advisory Committee on Reactor Safeguards (ACRS), an independent body of experts that advises the NRC on reactor safety matters. An ACRS subcommittee is expected to discuss the SER during a public meeting Sept. 5 at NRC headquarters. The full ACRS will later issue a report discussing the results of its review.