By AP/KWMU
St. Louis – Ameren's Callaway nuclear plant has been shut down for the second time in a week.
The company says problems in a steam valve prompted crews to power down the plant near Fulton Wednesday evening.
Ameren says the problem occurred in a part of the Callaway plant separate from the nuclear reactor and poses no danger to the public.
On Friday, the Callaway plant was shutdown because of high vibrations in a power turbine prompted a shutdown Friday. The facility re-opened without incident.
Ameren says it has not found a connection between the two incidents.