Southeast Michigan’s Fermi 2 nuclear power plant will shut down so its owner can install a refurbished feedwater pump that will enable the reactor to operate at full power for the first time in more than a year.
The pump, one of two that feed cooling water to the reactor, had a “catastrophic failure” in June, 2012, apparently due to a lubrication problem, said plant owner DTE Energy. The damaged pump and related equipment ended up sent off site for repair and refurbishment. During that time, the reactor was operating at 68 percent of power.
Once the repaired pump ends up reinstalled, utility officials said they expect to be able to resume operating the reactor at 100 percent power.
“Due to market considerations, we can’t say exactly how long the shutdown will be,” said Guy Cerullo, DTE spokesman. “I can say that the scope of this outage is limited. We will reinstall the feed pump and will be performing a limited number of other jobs to take advantage of the time offline.”
Earlier this year, the Nuclear Regulatory Commission (NRC) concluded that improper reassembly after maintenance, inadequate maintenance testing, and restarting of the pump out of normal sequence led to the pump breakdown.
The NRC said the utility violated operating rules because it “failed to appropriately oversee the overhaul of the (pump) by a vendor, and the post- maintenance testing and operation of the (pump) during and after” a refueling outage.
During a refueling outage, the plant shuts down and part of the nuclear fuel inside the reactor ends up replaced while workers conduct other routine maintenance.
DTE officials had said the pump breakdown never had an impact on plant safety. The NRC said although rule violations led to the pump damage, the event had “very low safety significance.”
The pump failure also caused operators to shut down the reactor, and it was among the too frequent unplanned shutdowns that prompted an extra NRC inspection of the plant earlier this year.
An NRC report on that extra inspection, issued last week, found no problems or areas of concern, and the plant has been returned to a regular inspection schedule.
The Fermi 2 plant near Newport began operating in January, 1988, after a 20-year construction period costing $5 billion. It normally supplies about 15 percent of DTE’s electric generating capacity in southeast Michigan.