I'm always surprised that these web 2.0 sites don't pay people to surf and flag content. It doesn't take much google-fu to find all sorts of stuff on the clearnet that shouldn't be there. I understand that removing offending stuff from Google search itself is very difficult but the walled garden sites like tumblr are much easier as most of the offending stuff is usually linked together by repost and/or likes. Find one page doing something it shouldn't and follow the likes and reposts down the rabbit hole flagging and removing as you go along.