I think you did what most Redditors do and read the headline only.
The vast majority of the games are not played anywhere near the nuclear site. In fact, the closest site is a soccer stadium and even that is a 3 hour drive from the plant. Roughly 130 miles.
The article talks about the torch relay in the Fukushima prefecture. The closest torch route is the 9th route tomorrow in Okuma, roughly 7 miles from the plant. Note that all sorts of people carry the torch, not just athletes.