Plymouth, MA-based Pilgrim Nuclear Power Station, which has only five months to produce power before it is shut down, dropped to 23 percent of full power by Friday, based on the daily status report published on the Nuclear Regulatory Commission’s (NRC) website.
The power drop occurred as operators continue to troubleshoot a problem with a valve that regulates water flow into the reactor, according to NRC spokesman Neil Sheehan.
The reactor was reduced to 79 percent power Thursday to do a scheduled thermal backwash of the main condenser to remove mussel growth and to handle some maintenance.
Patrick O’Brien, spokesman for plant owner-operator Entergy Corp., said addressing the problem with the feedwater system was part of that maintenance.
The feedwater system at Pilgrim has been a source of chronic problems, particularly in the last few years. In 2018, the system malfunctioned at least four times. Problems initially occurred in early March and again in late April. In October, a valve unexpectedly closed, resulting in a sudden drop of the water level in the reactor. The plant’s protection system forced an automatic shutdown.
Entergy replaced some improperly sealed electrical connectors, along with several other parts, after the October incident.
On Nov. 2, operators powered the reactor down to 35 percent to troubleshoot feedwater system issues again.
Pilgrim has only five months left of operation. It is scheduled to permanently shut down by June 1.
On top of that, the NRC will hold a public meeting in Plymouth Jan. 15 to discuss and accept public comments on Entergy Nuclear Operations, Inc.’s Post-Shutdown Decommissioning Activities Report for the Pilgrim facility, which entered commercial operation on Dec. 1, 1972. The report calls for placing the plant into long-term storage before dismantlement and decontamination work begins.
Pilgrim is the only nuclear power plant operated in Massachusetts.
The NRC staff also will present a webinar on Jan. 8 for interested members of the public to participate in discussions regarding the decommissioning of the plant. The webinar will begin at 2 p.m.. It will provide key facts about the decommissioning process and explain how NRC regulates such activities through on-site inspections and other reviews.
Webinar participants will be able to view slides prepared by NRC staff and ask questions in writing via a web page set up to host the session. Online registration is required to participate.
Holtec Decommissioning International plans to acquire Pilgrim and conduct an expedited decommissioning of the plant. The commission is reviewing the license transfer application.
Entergy plans to use the SAFSTOR decommissioning method. Its report explains the SAFSTOR approach means that, after a plant is shut down and defueled, the facility is placed in a safe, stable condition and maintained in that state (safe storage). The facility is decontaminated and dismantled at the end of the storage period to levels that permit license termination. During SAFSTOR, a facility is left intact or may be partially dismantled, but the fuel is removed from the reactor vessel and radioactive liquids are drained from systems and components and then processed.
The report includes a table showing the entire period from shutdown of the plant to license termination will last 60 years.