Extra steps taken for nuclear backup systems
Bridgeman, Mich. — In March 2011, a powerful earthquake struck off the east coast of northern Japan, setting off a chain of events leading to the worst nuclear power plant disaster since Chernobyl in 1986.
The Fukushima I nuclear power plant was immediately shut down as a precaution. But when a gigantic tsunami triggered by the earthquake hit the coastal power plant about an hour later, the huge wave topped the 19-foot seawall.
The tragic result was that flooding in the plant disabled backup generators used to pump cool water into the reactor cores to prevent overheating. The water did overheat, and in turn caused several explosions. The disaster led to the release of radiation into the sea and into the air.
It didn’t take long for the federal Nuclear Regulatory Commission to analyze what went wrong at the Fukushima plant and learn what could have been done to prevent it.
More importantly, NRC staff wanted to know how the lessons learned from the Japanese disaster could be used to boost domestic nuclear power plant disaster safety.
Within a year of the disaster, the NRC issued additional regulatory orders for U.S. nuclear power plants. All the plants are expected to have the new requirements in place by late 2016, or sooner.
Southwest Michigan’s two nuclear power plants have or are building hardened “bunker” style buildings to house emergency backup equipment such as hoses, diesel generators and backup pumps, as required by the NRC.