What it’s like to stand on top of a nuclear reactor

As someone who gets his nuclear power station knowledge from The Simpson’s. What’s the blue stuff? Are they the rods or are they further down? Given you aren’t wearing protective clothing, are you far enough away to not get a high dose of radiation or is it just not very radioactive down there?

Even knowing that the water is absorbing the radiation, and the blue glow is confirmation of that, this still gives me chills.