Officials with FEMA, TVA and the local EMA said Friday that a multi-agency emergency exercise involving Browns Ferry Nuclear Plant was a success.
The drill, held Wednesday at the plant and Thursday in Florence, involved about 1,000 employees from TVA, the state and first responders from Limestone, Lawrence, Lauderdale, Madison and Morgan counties.
The exercise was based on a scenario created by a TVA team that involved related and unrelated events to test the players’ preparedness.
The mock emergency first began at 8 a.m. Wednesday with a flammable acetylene mixture that created an explosives hazard that required an alert, according to Walter H. Lee III, manager of emergency preparedness for TVA.
Though there was no explosion in the scenario, the plant’s fire team was dispatched and teams from TVA’s technical support center, operations support center and central emergency control center in Chattanooga were called in to start working. Actions were taken to stop the acetylene leak, evacuate the area and remove the explosive content from the air.
In an unrelated event, a control line on the Unit 2 reactor failed as crews increased power from 40 percent after a planned maintenance outage. That resulted in the crew in the control room manually tripping the reactor to shut it down.
“We had a high-powered condition in which the (fuel) rods did not insert into the core and that caused some fuel damage that allowed radioactivity to flow into the reactor coolant system which raised the radiation levels of the plant,” Lee said.
Another part of the scenario addressed core damage and a failure to isolate radioactivity, which resulted in a site-area emergency. The plant began taking steps to ensure the plant was being cooled down and depressurized.
Subsequent to those mock crises, the scenario called for a pipe outside the containment structure leaking, meaning radioactivity is then spread to the environment. Lee said that portion of the drill led to a general emergency that required an evacuation of a 2-mile radius around the plant and five miles downwind of the radioactive plume.
After surveying the wind speed in the scenario, the evacuation zone was extended to 10 miles downwind of the plume.
“We continued to take actions to close and isolate the leak and send our field teams to evaluate and verify the dose models,” Lee said. “At around 3:30 p.m., we assumed we had a complete failure and that allowed more (contaminated) water to exit. We had field teams dispatched from the plant to work in conjunction with the state teams.”
As all these events were unfolding, TVA set up a communications center at Calhoun Community College to provide mock press releases and briefings to ensure the public was given adequate information.
On a local level, officials with the Limestone County EMA activated its Emergency Operations Center and notified public officials and began preparing public statements.
“It was a very good practice for us,” said director Rita White. “We just continued to work through it as the scenario went along.”
Daphne Ellison of the Limestone EMA said the drill was a success, though the agency continues to find room for improvement in the area of communication.
“We learned a lot of things during the storms, and we added more radios and a phone bank,” she said. “There are just a lot of things for us to look at and think about.”
Lawrence Robertson with FEMA’s technological hazards branch said the exercise was very successful and unusual because it involved the plume exposure pathway, which is what led to the mock evacuation.
He said the exercise was originally scheduled for June, but was delayed because of the April 27 tornadoes that hit the area.
“There were a lot of good discussions and a lot of interaction and the things we’re always impressed with is how well the counties and state works together,” Robertson said.
He said FEMA surveys how emergency operations work together in the exercise and how those agencies send alerts and make other decisions regarding public safety.
“For the people who play in the actual exercise, we have our criteria we look at,” he said. “We have evaluators all over the country looking at these exercises and may offer improvements based on what they’ve seen in other places.”
In 90 days, FEMA will issue a full public report on how the agencies performed during the exercise.
Also observing the exercise were officials from the U.S. Nuclear Regulatory Commission. Mark Speck, Region II senior emergency preparedness inspector, said the drill was an adequate test of the plant’s emergency plan.
He said there are four standards that must be met, including: the licensee’s ability to evaluate the event; classify the event correctly; notify state and local authorities of the classification; and to evaluate the potential radiation dose to the public and make recommendations to the state for protection areas.
“Based on that evaluation, we had no significant issues, but we had some observations for improvements,” Speck said.
The NRC’s report of the exercise will be available to the public by the end of January.