Duke Energy spokesman Ryan Mosier said earlier this week that operators of the two plants would begin shutting down the plants at least two hours before Florence's hurricane-force winds arrive.
Tropical Storm Florence dumped "epic" amounts of rain on North and SC as it trudged inland on Saturday, triggering risky flooding, toppling trees, cutting power to almost a million homes and businesses while causing at least five deaths.
Duke Energy did not provide information about specific changes made at Brunswick, other than to say emergency generators and pumps will remove stormwater if the plant floods.
According to a 2004 NRC report, Brunswick was rated to be waterproof against a storm surge of up to 6.7 metres (22 feet). On its current track, the storm will hit the coast on Friday with maximum sustained winds of about 105 miles per hour.
The Brunswick plant's two reactors share the same design as those in Fukushima, Japan, that exploded and leaked radiation following a 2011 natural disaster and tsunami.
Brunswick Nuclear Plant shutting down
He added: "Those power plants are, one, obviously hardened".
"This is no ordinary storm and customers could be without power for a very long time - not days, but weeks", said Fowler.
Engineers and staff will be remaining on site at the plant to monitor the situation.
Since Fukushima, all USA reactors have been upgraded with additional safety equipment, including portable pumps and generators to keep cooling water circulating through the reactor in case the plant loses offsite power.
In preparing for Hurricane Florence, the NRC statement said that the staffs at Brunswick, Surry in southeastern Virginia, Harris near Raleigh, N.C., Robinson near Hartsville, S.C., and some other plants are working through their severe weather procedures, including ensuring that all loose debris and equipment have been removed or secured, and conducting walk-down inspections of important systems and equipment.
While there is little chance of a nuclear accident due to Florence, there is a bigger concern to public health from the storm - toxic waste.
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