A: There are a few events which cause extreme levels that will never go away, but most radiation from things like blown up cars( nuclear engines) and the mini-nuke weapon will dissipate given a little time.

• 答：有些事件会造成严重的永久性辐射，但是绝大多数辐射是来自炸掉一辆核引擎汽车和微型核武器，而这些是会在不长时间后消失掉的。