Re: 120-ml and tool monitor

[Gv1@aol.com]

All,

Some level of communications took place with the NRC and our utility a few 
years ago regarding small volumes of liquids and tool monitors.  I believe 
the NRC recognized that it would be exceeding difficult/lengthy to attempt to 
achieve the LLD values put forth in the ODCM tables for small volumes of 
liquids (50 ml or less).  In such cases where this was the only amount 
available, such as an important oil sample for a piece of equipment and the 
oil could not be combined with another volume of oil, then the use of the 
tool monitor would be acceptable.  Most oil sources can supply the minimum 
500 ml we require to meet the ODCM LLD values.  Our 500 ml count is 3.5 hr 
and our 1600 ml count is 1 hr.  

If you are just sending oil samples to a licensed lab, you would not need to 
analyze to unconditional release LLD values to say the oil is less than 70 
Bq/g.  You might consider looking at the state regs, working out an 
achievable LLD with the lab, and conservatively use some form of courtesy 
statement saying your oil contains radionuclides below some LLD value...  I 
don't think I've ever seen any shipping related LLD values except for what is 
in 10CFR61.

With respect to waste liquids, just combine them until you get at least 500 
ml and count to the ODCM LLD values.

I personally would recommend a 10 minute QI count on a Ge detector rather 
than using the tool monitor.  While the small geometry may not be 
quantifiable, a 10 minute Ge count is going to be more sensitive than a 10 
second tool monitor count.

A small tube of grease is an interesting item.  The tube itself is an item 
much like what would be monitored in a tool monitor, but the grease inside 
might well be considered a "volumetric" material and be tied to your ODCM LLD 
values.  Most procedures would probably stumble a bit here.

Our site uses a 50 ml cutoff with the inclusion of the previous logic and the 
approval of the RP Manager.  This is not a routine method of releasing 
materials.

Sincerely,
Glen Vickers
Braidwood Nuclear Station
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