Re: Radon Control During Remediation

[Chris Alston <alstonc@odrge.odr.georgetown.edu>]

It's not clear why radon should be an issue in connection with the handling
of DU. Du is essentially U238 and its first two daughters, Th234 and Pa234.
If you take a look at the decay series, you'll see that the next daughter is
U234 @ t1/2= 2.5E5y. The next is Th230 @ 8E4y. Only then do we come to Ra226
@ 1602y. There hasn't been time for ingrowth of the Rn producer. Am I
missing something here?

chris alston
Opinions are my own alone.

At 09:28  01/08/98 -0600, you wrote:
>          Hello Radsafers;
>          
>          Rocky Flats will shortly begin remediation of an area known as 
>          Trench 1 (T1) where ~125 drums of depleted uranium (DU) chips 
>          and lathe coolant were buried from 1954 until 1962.
>          
>          The work will involve excavating the drums and stabilizing the 
>          potentially pyrophoric DU, in place.  All work will be 
>          performed inside a very large tent to be constructed over the 
>          site.
>          
>          My question concerns the generation of Radon and decay 
>          products from the DU (primarily U238) during the work. Are 
>          there any regulatory drivers, etc. to require monitoring 
>          worker exposure to the Radon products, as would be the case in 
>          a uranium mine, since the Radon is being generated from 
>          man-made materials?
>          
>          We intend to air-sample and monitor (with CAMs) for uranium.
>          
>          Thanks for any input Radsafers might have.
>          
>          Bates Estabrooks
>          bates.estabrooks@rfets.gov  
>