Re: Re[2]: U-238 in Groundwater

[Franz Schoenhofer <schoenho@via.at>]

Hi Alex,

Thank you for your comment, which gives an interesting insight into the
legislation of another country. It is of particular interest since the
European Union is now struggling for a drinking water directive.



At 17:57 18.05.98 -0500, you wrote:
>Hi Franz
>
>What do you mean by "fixed"? 

By "fixed" I meant that a strict limit is given in legislation, above which
level the water must not be used for drinking purposes. Such fixed levels
would be in contrast to "recommendations" or even more to "proposals". 

The current Australian Drinking Water Guidelines
>(1996) specify gross alpha (0.1Bq/liter) and gross beta (0.5 Bq/liter,
excluding
>contribution from K40) as screening levels. If either of these screening
levels
>are exceeded, radionuke analysis must be undertaken, and a dose assessment
done
>with the "limit" set at 0.1mSv per annum (excluding K40).

This is rather close to the WHO guidelines and recommendations. The
difference is that the WHO recommends 1 Bq/l for gross beta. What about
radon? 0.1mSv/a from radon in water is easily achieved from most water
supplies. Unfortunately the European Union Parlament wants to have the WHO
screening values introduced as  l i m i t s . (!!!!!) The maximum tritium
concentration should be cut to 100 Bq/l.

 For uranium only, a
>guideline value of 20ug per liter is recommended. mmmmmmm, I suppose this
isn't
>really "fixed" is it, as it is only a recommended guideline, but here in
>Australia, guidelines such as this tend to be picked up in regulation. 
Did I
>mention that the Australian Drinking Water Guidelines are under review, and I
>believe they are moving away from specifying individual radionuke levels, and
>towards critical group dose estimation???

More information about this might not only be of interest to me, but also
to other RADSAFERs.


Franz


Franz Schoenhofer
Federal Institute for Food Control and Research
Department for Radiochemistry and Radioactivity of Food
Kinderspitalg. 15
A-1095 Vienna
AUSTRIA
tel.: +43-1-40491-520
fax.: +43-1-40491-540