Re: Decommissioning problem

[ptyree@cisusinc.com]

Greg Krause <greg_krause@operations.und.nodak.edu> SAID:

"Just some clarifications on my first post:

The fuel has been gone for over a year so if the contamination is from the radon
daughters, its not new stuff, only long lived remnants.  However, for 20 years
the Uranium and the  Al components were in a room with more than a 700 pCi/l Rn
concentration."

Greg,

20 years'immersion in 4n+2 series decay product from >700pCi/l Rn air has likely
accumulated a significant coating of Radium DEF, i.e.,T1/2=22Y Pb-210, with
daughters Bi-210(5 D.,Beta) and Po-210 (138 D.,Alpha) in equilibrium,..so your
paper towels should be taken seriously if you choose decontamination.

I hope this info helps.

Paul Tyree, RSO
CIS-US, Inc.
ptyree@cisusinc.com    www.cisusinc.com


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