Water/Ice is one of the best radiation shields out there. A meter of water will block everything but the most high energy rare cosmic rays. One of the Mars proposals is to have a "RAD-Room" inside one of the water tanks/fuel tanks of the spacecraft. The bad thing about this is that water is heavy. a cubic meter of water is a ton, and you need a lot of cubic meters of water to make a room like this. If Europa has a mile or two of ice on the surface, then water under that, which is what it is starting to look like, then the ocean under the surface won't have that much radiation flux. The surface of Europa is going to be hell to work with as Europa goes right through the bad parts of the radiation belts, but anything that manages to live in that ocean should, at least on paper, be fine. JunoCam is another feature that the Planetary Society, among others, had to fight tooth and nail for and the images of the polar regions of Jupiter are asking a whole set of questions nobody knew to ask 10 years ago. With the orbit stuck in the big loop, there is hope that they can get some images of the poles of Io and Ganymede as well.