Re: Sewer Disposal & Plumbing

[melissa (M. Woo)]

There's something that's puzzling me here... 

I can put introduce a solution containing a radionuclide that is soluble
at the time I put it into a laboratory sink.  A minute later, I can put 
another solution, not necessarily radioactive, that will cause the
radionuclide in the previous solution to precipitate out.  Alternatively,
someone else in the sewage chain could introduce something that, when
concentrated with my radioactive solution at the sewage treatment plant,
might, despite the presumably tiny concentrations of each at the time it
hits the treament plant, cause the radionuclide to precipitate out over
the course of time.

I can see that one might wish to determine solubility/insolubility before
it's ever put down the sink in order to reduce total volume of insolubles,
but I wonder if post-lab sink chemical reactions have been considered (or
does it really matter, anyway?).

-- 
Melissa Woo                       | University of Illinois at Urbana-Champaign
Health Physicist                  | Environmental Health & Safety Bldg., MC225
office phone: 1.217.244.7233      | 101 S. Gregory St., Urbana, IL  61801
m-woo@uiuc.edu                    | http://www.cso.uiuc.edu/ph/www/m-woo