There was a really cool program on PBS a while back about this:
http://www.pbs.org/wnet/nature/radio...-episode/7190/
Apparently the cancer rate among the wildlife is quite a bit higher than normal in that area. However the fact that there isn't any human interference is a big plus for the animals and far outweighs the negative impacts of the cancer.
In other words people are a bigger problem for animals than radioactivity.