(03-25-2011 12:21 PM)Brookes Owl Wrote:  From the log: "...seawater injection continues..." How does this work? Where's the "spent" seawater going?

Good question, and I don't really know. Some of it is evaporating, some is probably running off into the ocean. The idea of the torus around the reactor base is to filter out radioactive isotopes and cool the steam coming out of the reactor. I'm not sure how much of those elements are coming out into the facility grounds and/or directly to sea, but I'd expect that there is more release that's going to sea at this stage than is going outside of the plant grounds on land through the air.

To what extent that poses a danger will probably depend on monitoring. But over time, it will be dispersed into the sea and probably won't concentrate in any one area enough to be very dangerous.

Two notes on the isotopes that are being discussed as primary dangers - these are the ones that would be released through the spent fuel pools. The shorter-lived isotopes generally should have decayed inside the reactor by now. Radioactive iodine has a half-life on the order of 8 days. Within three months, it is effectively "gone" from the location of its release, assuming relatively small quantities, to (it would go to 1/1024 the initial concentration, which has thus far been pretty low outside the plant grounds). Cesium has a half life of 30 years. That's the one that has been of concern in and around Chernobyl. Basically, the shorter the half-life, the more "active" it is in terms of giving off radiation. The danger that each isotope has depends on the type of radiation it gives off, the chemical properties of the isotope, and how it interacts with the body.