I have been asked what I think is the worst that can happen in Japan with the nuclear accident.
Sadly neither myself or any other person has a crystal ball which tells us what the future will hold. But I do not think it will be as bad as Chernobyl. It is important to bear in mind that a loss of cooling accident tends to progress more slowly than a reactivity accident (RIA). Chernobyl and SL1 were a sudden reactivity accidents. The accident in Japan and the Three Mile Island accident are both loss of cooling accidents (LOCAs)
What we do know is that the Japanese are still working to bring the reactor site under control. The radiation levels are higher than normal at the site. You can read more about what is going on at the following sites.