Iowa’s elderly Duane Arnold nuclear power plant, scheduled to go out of service on Oct. 30, won’t restart after the region’s 100+ mph derecho wind storm severely damage the plant’s closed-cycle cooling system. A spokesman for Florida-based NextEra Energy, the current owner of the 46-year-old plant, said, “After conducting a complete assessment of the damage caused by recent severe weather, NextEra Energy Resources has made the decision not to restart the reactor.”
The 615-MW General Electric boiling water reactor, with a suspect Mark 1 containment, automatically scrammed from 82 percent power on August 10, according to the U.S. Nuclear Regulatory Commission. The NRC noted damaged to the plant, but not to the reactor building. NextEra’s spokesman said the damage to the cooling units was “extensive” and replacing them before the planned October shutdown was “not feasible.”
Duane Arnold, Iowa’s only nuclear plant, is located near Cedar Rapids, the state’s second largest city after Des Moines, and draws cooling water from the Cedar River. It gets its power from a GE BWR 4 reactor. NextEra owns 70% of the plant and is the operator. Central Iowa Power Cooperative owns 20% and Corn Belt Power Cooperative owns 10%.
In the late 1960s, during the boom years for nuclear power, Iowa Electric Light & Power, now Alliant Energy, and the two large rural electric cooperatives applied to the then Atomic Energy Commission for a construction permit. The AEC granted the permit and work began in June 1970. The planners expected the unit to be operating in 40 months, at a cost of $250 million.
Duane Arnold, named for the IEL&P CEO who was a nuclear enthusiast, went critical in March 1974, at a cost of $300 million.
Unlike later plants with massive conical cooling towers, Duane Arnold has 24 low-rise mechanical draft cooling towers. The site has dry case storage for spent fuel, which likely will be an issue when decommissioning begins.
— Kennedy Maize