Nah. It’s not like there’s not unexploded bombs all over Japan and Germany. I read an article not long ago about a farmer who blew himself up plowing up a bomb.
Bombs are dug up around Tokyo all the time. A few years back a big 500lb bomb was dug up just next to the train tracks near my house. There is always so much construction in Japan that they are found with some frequency, but we only hear about the really interesting ones.