The Nuclear Regulatory Commission (NRC) said on Tuesday it will increase oversight of Exelon Corp's 805-megawatt Three Mile Island nuclear power plant in Pennsylvania, to ensure that safety equipment is protected from flooding.
As part of agency's numerous inspections of the nation's nuclear reactors following the Fukushima nuclear accident in 2011, the NRC said its inspectors identified an external flood barrier deficiency during a plant walk down last autumn.
Specifically, the NRC said the inspectors determined that the company had failed to identify and correct a problem involving pipes holding electrical cables.
The pipes, located in the plant's air intake tunnel, were not adequately sealed to maintain the integrity of the flood barrier, the NRC said.
In the event of severe flooding, the NRC said the problem had the potential to pose a threat to plant safety equipment.
Three Mile Island, the site of a partial nuclear meltdown in 1979, is on an island in the Susquehanna River about 15 miles southeast of Harrisburg, the Pennsylvania state capital.
The NRC said Exelon has since taken action to fix the problem.
The NRC uses a color-coded system to classify inspection findings, which range from green, for a safety issue of very low significance, to red, for a safety issue of high significance.
In this case, the NRC said it determined the inspection finding should be categorized as white, or a safety issue of low to moderate safety significance.
The NRC said this white finding will result in additional scrutiny until the agency is satisfied the issues have been properly evaluated and corrected.
(Reporting by Scott DiSavino)