State and local police vehicles and ambulances that rushed past residences on Route 144 for a “simulated intrusion” at Maine Yankee Wednesday morning concerned some residents, since it occurred the day after a minor earthquake. Maine Yankee Government Affairs Director Eric Howes confirmed the incident was just a drill and had nothing to do with the earthquake. The decomissioned nuclear power plant held its biannual Emergency Plan Exercise, required by the US Nuclear Regulatory Commission, on October 17. 

The exercise involved a team of “attackers” attempting to cause damage to one of 60 casks at the site containing spent nuclear fuel using explosives. No actual explosives were used in this exercise. Responders to the scene engaged with the attackers, tended to the “wounded” and secured the area with mock police barricades. 

Those who responded to the scene were personnel from the Maine State Police, the Lincoln County Sheriff's Department, the Wiscasset Police Department, Lincoln County Emergency Management, Maine Emergency Management, Wiscasset Fire Department and the Wiscasset Ambulance Service, as well as Maine Yankee staff members.

“It is an attempt to make this (scenario) as real as possible,” said, adding, “There is no credible scenario that would result in a breach of a cask.”

The spent nuclear fuel is housed inside 28-inch airtight sealed steel containers. These containers are further enclosed by large steel and concrete casks on concrete pads, according to the website (www.maineyankee.com). 

Howes said the likelihood of breaching one of these casks is small. Also, dispersal of any radioactivity would not occur as it would in a working power plant. Since Maine Yankee is not operating, there is no mechanism to disperse radioactive material, according to Howes. And emergency planning is limited to the site.

However, any outside damage to casks has to be assessed. That's where State Nuclear Safety Inspector Pat Dostie gets involved. Part of his job in such a scenario would be to measure radiation levels as a result of the damage and any potential impacts of the “attack” to the surrounding community. He said this work would involve different people, from contractors to security personnel.

By all official accounts, it was a successful exercise. “I think it went very well,” Howes said. Had it been a real incident, however, Howes said the process would have taken a lot longer, from several days to weeks. The state police would normally conduct a more extensive sweep of the area to identify all potential threats and the extent of damage would also determine the length of time needed for clean up efforts.