Repairs underway at Exelon PA Three Mile Island reactor

Sept 21 (Reuters) - Exelon Corp said it was
conducting repairs on a reactor coolant pump at the 805-megawatt
Unit 1 of its Three Mile Island nuclear power plant in
Pennsylvania, which shut down automatically on Thursday
following a malfunction.
"The cause of yesterday's shutdown was a problem with a
reactor coolant pump," company spokesman Ralph DeSantis said.
He did not specify any return date for the unit.
----------------------------------------------------------
PLANT BACKGROUND/TIMELINE
STATE: Pennsylvania
COUNTY: Dauphin
TOWN: Middletown about 10 miles (16 km) southeast of
Harrisburg, the state capital, on the Susquehanna
River
OPERATOR: Exelon Nuclear
OWNER(S): Exelon
CAPACITY: 805 MW
UNIT(S): Unit 1 - 786-MW Babcock and Wilcox pressurized
water reactor
Unit 2 - 802-MW Babcock and Wilcox pressurized
water reactor - owned by FirstEnergy - out
of service since the 1979 accident
FUEL: Nuclear
Dispatch: Baseload
COST: $400 million for Unit 1

TIMELINE:
1968-70 - General Public Utilities Corp, later named GPU
Inc, built the reactors. It was operated by GPU
subsidiary Metropolitan Edison Co (Met-Ed)
1974 - Unit 1 enters service
1978 - Unit 2 enters service
1979 - Partial meltdown of Unit 2 - the NRC said the
accident did not result in any deaths or injuries
to plant workers or the nearby communities. Unit 1
was shut for refueling during the accident and was
kept shut until 1985
1985 - Unit 1 returns to service
1999 - GPU sells Unit 1 to AmerGen Energy Corp, a joint
venture of Philadelphia Electric Co (PECO Energy)
and British Energy Group Plc
2000 - PECO Energy and Unicom merged to form Exelon Corp
2001 - GPU merged with FirstEnergy
2003 - Exelon buys British Energy's stake in AmerGen and
transferred it to Exelon Nuclear
2009 - NRC extends original 40 year operating license for
Unit 1 for another 20 years
2010 - NRC said the generator from Unit 2 will be used at
Duke Energy's Harris nuclear power plant in
North Carolina. The generator weighs 670 tons
2034 - Unit 1 license expires