A local group (some of whose members live in the pollution shadow) called Citizens Awareness Network has been colating the cases.  

Dozens and dozens.  

Believe me.  Believe them.  Or believe the Industry.  Your choice.  

The Fates are kind.

The right answer is sadly, "too many to count" in the US. In France, it does not happen often, although a few times we hear of accidents where radiation enters the wrong rooms and contaminate a worker or two. No death though. There were some in Japan a few years ago.

Also note that water-cooled reactors continuously release little amount of tritium in the atmosphere as part of their normal operation (the reasoning being that tritium is short lived and flows quickly through living organism, so it is safer to dilute it quickly and never accumulate large amounts that could blow up in one time, and leak anyway - it's still hydrogen and most metals are porous to hydrogen). One of the origins is neutron capture in the water of primary loop, it is extracted because it must be kept non-radioactive for quicker detection of a real leak from a rod.

Pierre