Source: Jeff Geuther, 785-532-6657, geuther@k-state.edu
News tip prepared by: Trevor Davis, 785-532-2535, tjdavis@k-state.edu

Friday, March 11, 2011

NEWS TIP: NUCLEAR POWER EXPERT SAYS JAPANESE REACTOR SAFETY PRECAUTIONS PUT TO TEST AFTER EARTHQUAKE

MANHATTAN — Kansas State University nuclear power expert says Japanese officials are taking proper precautions after the 8.9-magnitude earthquake March 11.

The Fukushima plant 150 miles north of Tokyo is a boiling water reactor that operates similarly to about a third of the nuclear power reactors in the United States, said Jeff Geuther, K-State's nuclear reactor facility manager. Nuclear fission heats and boils water, which produces steam for electricity. The water that is converted to steam also functions as the coolant for the reactor.

Emergency cooling systems stopped working after electricity outages and the failure of diesel back-up generators, according to Japanese media reports.

The Tokyo utility company that runs the plant is now working to cool the core's reactor, Geuther said.

"The generator and back-up power are intended to run in an emergency to cool the core of the reactor," Geuther said. "Even though the reactor is shut down, it's critical that the core is kept cool because much heat comes from radioactive decay."

If the core heats too much after a shutdown, it could result in an incident similar to 1979's Three Mile Island accident in Pennsylvania. 

"But just like at the Three Mile Island facility, the Fukushima plant has a containment structure, so any risk to the public would be minimal," Geuther said.

Thousands who live near the Japanese plant have been evacuated, which was done as a mandated safety precaution due to the loss of cooling, he said.

"It's critical we plan for the worst-case scenario," Geuther said. "These accidents are never from a single cause, but are the result of multiple things going wrong. These are complicated systems, so it's important, but not impossible, to take all necessary safety precautions."

The event could steer public perception of nuclear reactors in America, Geuther said.

"If this is resolved successfully — and I have the expectation that it will be — I will be curious to see if the general public sees this as a success or as a failure even if the Japanese avert any crisis,” he said.

Many new nuclear power plant designs, such as the 14 Westinghouse AP-1000 reactors planned for U.S. operation, are designed to make use of passive cooling and would not need pumped emergency coolant like the Fukushima plant, Geuther said.