Florida’s two nuclear power plants are set to shut down in time for Hurricane Irma, which is projected to hit the southern part of the state as a Category 5 storm on Sunday.
The Turkey Point and St. Lucie plants will be “gradually and deliberately” shut down as the storm approaches, for safety reasons.
The Turkey Point Nuclear Plant was expected to close on Friday evening and the St. Lucie Nuclear Plant is to shut down about 12 hours later, depending on the storm’s path.
The nuclear plants are located along Florida’s Atlantic Coast, about 20 feet (six meters) above sea level.
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Officials said the reactors will close as winds approach Category 1 levels.
The Nuclear Regulatory Commission has sent inspectors to the sites to ensure all proper protocols are being followed.
But officials say the sites are secure and should be able to weather the storm.
“The storm surge forecasts that we have seen so far do not challenge the sites’ designs,” said NRC spokesman Scott Burnell.
FPL, a subsidiary of NextEra Energy Inc, generates enough power for about 1.9 million homes at the Turkey Point and St. Lucie plants.
Irma could knock out power to more than 4.1 million homes and businesses served by FPL, affecting around nine million people based on the current storm track, the utility’s chief executive said.
Between the two plants, there are four reactors that date back to 1972 at the oldest.
Hurricane Andrew, another Category 5, passed over Turkey Point in 1992.
But this is the biggest test for nuclear reactors since the Fukushima power plant was hit with a tsnami in 2011.
Waters from the wave disabled backup generators, which led to a partial meltdown of the reactor. Nuclear radiation leaked out into the water and surrounding area.
Since then, regulations have changed to require plants to provide portable equipment to power the reactors.
“Things are better today than in March 2011. Time will tell whether better proves good enough,” said Dave Lochbaum, director of a watchdog group, the Nuclear Safety Project, at the Union of Concerned Scientists.
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Irma battered the Caribbean islands, leaving at least 21 people dead in its wake. It smashed homes, shops, roads and schools; knocked out power, water and telephone service; trapped thousands of tourists; and stripped trees of their leaves. It’s set to make landfall in the U.S. on Sunday morning.
*With files from Reuters and the Associated Press