A thriller is not a cozy mystery or a whodunit. It's a novel or play in which a threat to the life or well-being of the protagonist and/or other significant characters is paramount. Catastrophe will occur if the hero doesn't act decisively, and if necessary, with violence.
The stream of reactor disasters spewing from this dying industry is certain to escalate. The toll rises with each leak at Fukushima, every flame at Los Alamos, each legal brief at Vermont Yankee, every foot of Nebraska floodwater.
Although the Missouri River floods threatening Nebraska's Ft. Calhoun and Cooper nuclear power plants will put tremendous stress on both the systems and their operators, the immediate risk of a meltdown like Fukushima is small.