Tennessee Valley Authority (TVA) fixed the immediate problems that led to a serious safety violation at its Browns Ferry nuclear plant in Alabama, but it must still demonstrate long-term improvement, federal regulators said.
The initial findings by the U.S. Nuclear Regulatory Commission (NRC) come from an in-depth inspection triggered by a serious safety violation issued in mid-2011 against the plant near Athens, AL.
The NRC had issued only five such red findings — its most severe citations — up to that point. It came after the agency investigated how a valve on a cooling system on the Unit 1 reactor became stuck shut, which could have left equipment used to cool hot, radioactive nuclear fuel inoperable.
The plant still had other cooling systems. But the failure would have been a major problem during a fire since emergency plans called for preventively shutting down other equipment and using the damaged system.
Federal authorities were troubled because workers failed to quickly notice the broken valve, pointing to a weak safety culture. The equipment failure, uncovered in 2010, never caused a serious problem at the facility.
“They have a higher regard for a stronger safety culture at the station,” said NRC branch chief Eugene Guthrie, who oversees the federal inspectors at the plant and headed the in-depth inspection. “It starts there. But all of that needs to be reinforced in the worker behaviors as they perform their routine duties and responsibilities in the field.”
NRC officials still rank the Unit 1 reactor at Browns Ferry as one of the worst-performing nuclear plants in the country. Federal officials will rely on the results of future inspections and reviews to determine whether they upgrade the plant’s rating, which affects the level of NRC scrutiny it receives.
The TVA’s chief nuclear officer, Preston Swafford, called the inspection thorough and “appropriately intrusive.”
“TVA agrees with the NRC assessment that we have additional work to reach and sustain excellence,” he said.