More or less. The difference is that, if they really wanted to, they could very thoroughly clean the notebook and take most of the contamination off. I’m guessing they won’t because a) It’s a historical artifact and they don’t want to risk damaging it, b) the contamination is so low-level that it’s not dangerous as long as you don’t lick it or something, and/or c) there’s a bit of a shock factor in watching a scientist’s notebook make a Geiger counter freak out.