Ninety out of 94 operating commercial nuclear power reactors in the US were in the highest performance category and fully met safety and security performance objectives for 2020, the Nuclear Regulatory Commission said.

Three reactors were in the second performance category, needing to resolve one or two items of low safety significance, the NRC said. For this performance level, regulatory oversight includes additional inspection and follow-up of corrective actions. Plants in this category were Callaway-1 (Missouri); Clinton-1 (Illinois); and Surry-2 (Virginia).