Times staff and wires
Wednesday, March 16, 2011
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Photo by DAVID A. BROWN]
The nuclear reactor at the Crystal River power plant has been offline for 18 months due to cracks in its containment wall.
Of the nation's 104 nuclear reactors, five are in Florida, at three sites, including one at Progress Energy's site in Crystal River. The good news for Florida is none of the reactors are the same design as the ones in trouble in Japan.
Still, the specter of massive radiation leaks in Japan raises questions about our local reactor. Just how safe is it?
Could what happened to Japan's reactors happen at Crystal River?
Unlikely at any time, and even less so right now, since the only reactor at the Crystal River site has been offline for 18 months. Progress Energy announced Tuesday that additional cracks were found in the containment wall, which will keep the reactor offline past the planned April startup.
Presuming it comes back online, is the Crystal River plant able to withstand natural disasters?
Like the other nuclear power plants in the state, it is designed to take into account the most severe natural phenomena historically reported for the site and surrounding area, according to the state Division of Emergency Management. That includes earthquakes, tsunamis and the most powerful hurricanes
The Crystal River plant's close to the Gulf of Mexico. Does that make it more vulnerable?
The plant is built 30 feet above sea level. That would keep it safe from most storm surges. It also has other safety features to help protect it against a Category 5 storm surge, including watertight doors, said Progress spokeswoman Jessica Lambert.
And what about earthquakes and tsunamis?
The geology of our state makes an earthquake highly unlikely, though the plant is built to withstand some seismic activity. Tsunamis in the gulf are unlikely. Even if one occurred, it would likely start far enough away that the plant would have enough warning to shut down before it hit.
If seawater knocked power to the plant offline, could we experience the same problem as the Japanese currently face?
Unlikely. The plants affected in Japan are a different design. They use pumps to draw water up to cool the reactor. The Crystal River plant uses a closed loop cooling system that would not suffer the same problem. Emergency power sources would provide power to safety equipment if the plant lost power from the electrical grid.
Other than diesel generators, what does Progress have in place as backups?
There is more than one diesel generator serving as backup, as well as battery backups. Among other things, they can operate pumps to help remove water from flooding if necessary.
The Japanese sites had some of those backups, too. Why would they work here?
One big difference, Progress Energy officials said, between the Japan plants and Crystal River is that Japan's plants housed their fuel supplies for backup generators above the ground. Those supplies were apparently swept away at some point. Crystal River's backup fuel supplies are buried underground in sealed tanks and would be less vulnerable.
What is the biggest worry when it comes to natural disasters and the nuke plant?
Based on the Florida coastal location of the Crystal River plant and the area's geology, hurricanes are the most likely natural threat. Progress Energy would consider taking an operating nuclear plant offline in the event of a Category 5 hurricane, but that decision would depend on a variety of factors, including the storm's geographic cone of uncertainty. The company monitors weather and coordinates with state emergency preparedness officials to determine if the plant should be shut down.
What about the Levy County nuclear plant that Progress wants to build? Will that be a different design than the Japanese plants?
Yes. It will be a Westinghouse AP1000 reactor. It holds cooling water above the reactor core so that a gravity-fed stream of water can cool the fuel rods even if there is no electricity at the site. In Japan, the cores are overheating because the plants use power to pump cooling water into the reactors. That power was knocked out and the backup systems have failed, so the water isn't able to do its job.
In Japan, areas near the sites were evacuated and some of the people were told to shelter in place. What is the plan if one of Florida's sites has a potential leak?
Florida uses a 10-mile circle around each of Florida's nuclear power plants for emergency planning for evacuations, according to emergency management officials. For the Crystal River plant, that would directly affect about 25,000 people. (At nuclear plants operated in South Florida by Florida Power & Light, about 225,000 people would be affected at the St. Lucie site; at the Turkey Point site south of Miami, about 150,000 would be affected.)
Depending on the severity of the leak, the population would either be sheltered-in-place, or evacuated and sheltered outside of the 10-mile zone.
Has Progress Energy learned anything from what has happened in Japan that it will now apply to the Crystal River plant?
It's still very early looking at the situation in Japan and premature to speculate on lessons learned, Progress officials said. Both the national and international nuclear industry will glean and share any information about safety measures as this unfolds.
Fast facts
Plant information
The Crystal River nuclear plant was built in 1977 for about $400 million and includes one Babcock & Wilcox pressurized water reactor. It shares the 4,700-acre site with four coal-fired plants.
[Last modified: Mar 15, 2011 09:30 PM]
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