Emergency responders tested their plans to handle a disaster on Three Mile Island.
At the Lancaster County Emergency Operations Center, they ran through the plans for several hours on Tuesday. Responders in every county around Three Mile Island also participated.
They do this drill every two years, going through the steps of an evacuation of the 10-mile zone surrounding the nuclear plant. They estimate a full evacuation of every resident within that zone would take 8 and a half hours.
Some of the emergency responders were at the plant on Three Mile Island in the midst of the 1979 meltdown. They remember the chaotic evaluation then.
"They were scared because they didn't know and the absence of knowledge is fear," says Stuart Nelson, radiological officer for Lancaster County. He says he breathed in some radiation at that time but is now a healthy 74-year-old.
He points out there was no way to predict the earthquake that caused a meltdowns at the Fukushima nuclear plant in 2011.
"Something bad's going to happen and what you do is, you deal with it," says Nelson.
Evaluators from FEMA watched emergency responders in action to identify any glitches.
"It's key because of the reputation, so it's really important to show the people of Pennsylvania and this area that they're safe," says Dennis Wilford, an evaluator for FEMA.
Wilford reviews power plant emergency plans around the country.
"I've read their procedures, they have very good procedures, they have very good staff, very good equipment," he says of Lancaster County. "I don't expect anything less than perfection."
Within 30 days, local responders will get a written report with any changes they need to make to the plan.