Iowa’s only nuclear power plant is back online. The Duane Arnold Energy Center was taken offline after engineers found a leak. A management company in Wisconsin responsible for operating the plant northwest of Cedar Rapids announced it was a small circulating water tube leak in the main condenser system, and said there was no cause for alarm, though the discovery triggered a shutdown at 3:30 in the morning back on October 25th. After repairs were done the plant operated at low power while the maintenance staff worked to fix a vibration blamed on a regulating valve that controls water flow to the reactor. About 2:00 Friday afternoon the plant was brought completely back online. Duane Arnold generates enough electricity to serve 432-thousand homes. The plant’s owned by Alliant Energy Interstate Power and Light Company, Central Iowa Power Cooperative and Corn Belt Power Coop.