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Re: La Hague - 90000 times increase in air radioactivity
Bjorn,
Do you have the release handy? I could use some more info on times here,
but if this was some isolated short burst of Kr-85, someone may have done a
controlled release of Kr-85 from a fine leak detector system during
decommissioning. The idea behind this device for those that have never
seen such a creature, is that you place a ceramic packaged microchip into a
little pressure well, evacuate the air, pump in Kr-85 mixed with dry
nitrogen for a certain amount of time at a certain pressure (above
atmosphere) and then, after you put the Kr and N back into the storage
tank, pull the chips out and put them in a 3" NaI well counting station.
If you have counts, the time and pressure you "soaked" the parts for tells
you how big the leak is (on the order of 10^-8 cc/min); on the other hand,
no counts, no leak. Very quick and easy test for MIL-STD requirement on
non-leakage of hermetically sealed parts.
An extremely outside chance comes from the stockpile at Oak Ridge (that's
where we buy ours from) but I really doubt that ORNL is dumping the stuff
when they get it for "free" from the decay of stuff they have on hand and
then sell it for a fortune. How much do we trust Greenpeace numbers
anyway? How did they ID the isotope?
Scott Kniffin
RSO Unisys Federal Systems, Lanham, MD
CHO Radiation Effects Facility, GSFC, NASA
mailto:Scott.D.Kniffin.1@gsfc.nasa.gov
The opinions expressed here are my own. They do not necessarily represent
the views of Unisys or NASA. This material has not been reviewed by my
manager or NASA.
At 01:33 11/10/98 -0600, you wrote:
>Radsafers,
>
>I just got a message referring to a Greenpeace press
>release saying that the radioactivity in the air has
>increased by a factor of 90000 (Kr-85). I wonder if
>any of you has any further information so that this
>can be understood better (dose estimates for instance).
>They probably compare with some world average. The
>basis for the release is their own measurements.
>
>Sincerely Yours,
>
>bjorn_cedervall@hotmail.com
>Website: http://www.geocities.com/WallStreet/Exchange/8256/
>Any opinions expressed above are those of mine and may not necessarily
>coincide with those of others.
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