Reply #5: I would expect fuel fragments and reactor internals [View All]

[Throckmorton]

that may have been stored in the spent fuel pools to be much hotter than 900 milliserverts/hour. I have personally measured rates in excess of 100 severts/hour on used incore detectors (well shielded by refueling pool water of course, measured with a tele-tector). Control Element Assembly extension shafts, which are often stored in the spent fuel pool, also have dose rates around 5 severts/hour on contact on the end nearest the active region of the fuel.

Fresh spent fuel is far hotter than either of these examples, I asked an RE tonight about dose rates off of newly removed fuel (less the 60 days sub-critical) and he said 300 severts/hour for a once burned assembly, and 400 severts/hours for a twice/trice burned assembly is very common. These are all Gamma Doses, as alpha and beta particle dose rates are not directly measured due to the immersion of the fuel in water.

So, given this I see at least 4 possibilities:

1. The explosions did not entrain any material from inside the spent fuel pools and the reading are accurate.
2. The dose rates as reported are from much further away then the 1 meter (3 feet actually) that I am normally accustomed too (closer readings are prefaced with the distance, 'on contact, at 1 foot ...'.
3. They aren't looking for the right activation products (unlikely if general survey instruments are being used, as they are not that selective).
4. They are lying/withholding information about the hottest places (cherry picking the data).