But crucially, commercial spent nuclear fuel is in containers. Spent waste from weapons development was often just dumped in a pit and buried. Our priorities were very different in the 1940s and 50s. Seriously look at this picture [1]. That encapsulates the attitude towards nuclear safety during the early cold war. The soviets just dumped their waste into a lake [2]. Not to mention we detonated a thousand or so nuclear bombs, many of them above ground.

1. https://en.m.wikibooks.org/wiki/History_of_Nevada/Nevada_and...

2. https://en.m.wikipedia.org/wiki/Lake_Karachay