Watts Bar Nuclear Power Plant in Spring City is being inspected by the National Regulatory Commission (NRC). The NRC said the special inspection surrounds voids in the residual heat-removal system, which is used to complete the plant’s cool-down process. The voids caused the residual heat-removal system to not operate for a period of time on both Unit 1 and Unit 2. On April 19, 2018, TVA informed the NRC calculation revisions had reduced the acceptable size of a void because of gases in the system. On April 21, 2018, the accumulated gas in the Unit 1 system was found to have exceeded the acceptable value, and on April 22, the same observation was made on Unit 2. The results of the inspection will be released later this year.