Re: Liquid waste tank decommissioning!

[Joe Christy <jchristy@SLAC.Stanford.EDU>]

At 09:10 AM 2/3/99 -0600, you wrote:
>Hello!
>
>What is the procedure for putting liquid radioactive waste tanks out of
>service? What I mean is if we were to replace an old tank with a new tank,
>how do we go about getting rid of the old one ( if we have some trace
>amounts of radioactivity still present)
>Any suggestions or comments are appreciated.
>
>Thank you.
>
>Latha Vasudevan	
-------------------
Latha:
		           
Depending upon the size, configuration, and components of the tank (and the
amount of radioactivity remaining in the tank), some of the options that
you may want to explore are:

1. Decontaminate the tank for free release.
2. Use the tank as a "strong tight" container for the transport/disposal of
LSA and/or SCO radioactive material [see 49 CFR 173.427(b)].
3. Recycle the tank through metal melting at:
	GTS Duratek
	Bear Creek Operations
	P.O. Box 2530
	1560 Bear Creek Rd.
	Oak Ridge, TN 37831-2530
	Customer Service: 800-663-2966

(For more info on GTS, visit their website at: <http://www.gtsduratek.com/>)

Joe Christy
E-mail: jchristy@slac.stanford.edu
-------------------------------------------------
Latha:

Since my first posting, I did some research on option #2 above.  

According to a joint NRC/DOT draft guidance on LSA and SCO material
(NUREG-1608), neither LSA or SCO can be used as their own packaging.  So,
if the "empty" tank meets the definition of LSA or SCO (see 49 CFR 173.403)
than it cannot be used as a "strong tight" container for the
transport/disposal of other LSA and SCO material.    

The draft NUREG gives the following example:  A shipper might have
large-diameter steel pipes that are internally contaminated.  The shipper
would not be permitted to package LSA radioactive material inside the
pipes, install ends on the pipes, and present the pipes with contents for
transportation as LSA.  The reason:  the contaminated pipes are themselves
considered to be contents requiring categorization and packaging for
transportation.  This constraint also applies to large process vessels.
Thus, a large vessel having no external radioactive contamination, but
having contaminated internal surfaces, even if subsequently filled with LSA
or other SCO, is considered to be radioactive material subject to the
regulations of DOT and NRC for packaging and transportation. 

I have heard that this NRC/DOT guidance document has been issued as
RAMREG-003 (a DOT guidance document) but I have not been able to put my
hands on it.  The final guidance may be significantly different from that
presented above from the draft document.  So, option #2 may still be a
possibility. 

One final note:  Under certain situations, LSA and/or SCO can be shipped in
bulk packaging with the conveyance serving the function of the "strong
tight" packaging. Specifically, LSA-I and SCO-I material can be shipped in
this manner [see 49 CFR 173.427(c)].  So, if the tank were filled with
solid low-level waste and the filled tank met the definition of LSA-I or
SCO-I material, then the tank could be used as a receptacle for LSA-I/SCO-I
waste material provided it were shipped on a conveyance that met "strong
tight" packaging criteria (e.g., in a closed transport vehicle).     

Sorry for any confusion. 

Joe
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