Re: Field Detection of Pu

[Craig Reed <jreed@utk.edu>]

The absence of beta in the presence if significant alpha would certainly be
an indicator of potential HEU/Pu.  Unfortunately, I wouldn't want to open
the alpha source "dry" enough to make that assessment possible.  A fidler
probe (i.e., thin crystal for seeing low energy photons) with a
multichannel analyzer might be of use with practice.  Might want to borrow
a Fidler probe from someone to see what the "background" spectrum will
allow in the way of MDA's for the non-DU radionuclides.

Craig Reed
Legacy Waste

Bates Estabrooks wrote:

>           RADSAFERs:
>
>           Maybe some of you all could offer a suggestion.
>
>           Rocky Flats will, in a few weeks, begin excavating a
>           1950s-vintage trench in which drums of depleted uranium chips
>           and turnings (mixed with cutting coolants)  were buried.
>
>           As each intact drum (highly unlikely), or its carcass with
>           contents (very likely), is excavated, we would like to know
>           rather promptly whether we have any "surprises" such as Pu or
>           highly-enriched uranium.  We know that large quantities of DU
>           are buried there, but since the facility also worked with Pu
>           and HEU, there is a small chance of these things being found
>           also.
>
>           Therefore, can anyone recommend a quick screen using field
>           instruments that we might be able to perform on each backhoe
>           bucket of stuff to indicate whether either of these fissile
>           substances (pu or HEU) are present in significant quantities?
>
>           We have a fairly broad range of portables including the SAIC
>           AP-2.
>
>           Thanks for your help.
>
>           Bates Estabrooks
>           bates.estabrooks@rfets.gov
>           303-966-3769