Tritium Stratification

[/I=J/S=PRESLEY/O=AECB.CCEA@mhs-atomcon.attmail.com]

I think that David's explanation for the Tritium Stratification
seems the most plausible when dealing with an outdoor body of
water.
As pointed out by another Radsafer, the weight difference should not
matter since the HTO is "dissolved" in the H20.

Another possible effect which I submit for consideration is the 
influence of the plastic lining of the pond. If Tritum is preferentially
exchanging into the plastic then there may be a "wall effect"
going on here.

This would be evident if enough measurements were taken to characterize
the tritium concentration gradient in the vicinity of the sides and bottom
of the pond.


I would like to see some of the measurements for my own curiosity.


James Presley
Atomic Energy Control Board

-------------------------------------------------
From: "David Bromwich" <davidb@plato.ens.gu.edu.au>
Subject: Re: Tritium stratification

I worked at Flinders University (South Auatralia) in 1974 in their
Earth Sciences Department.  There was some work being done on the
Blue Lake at Mount Gambier, using tritium dating of the different
aquifers feeding the lake. Dr Graham Alsison of the CSIRO had the
tritiujm measuring facility at what was the Waite Institute. I think
they were measuring the water at diffrent levels with Kuntz bottles
(they open at both ends at a predetermined depth and grab a sample.
You would find refrence to this sort of work in the Hydrology
journals.

If there is a sufficient (I dont know waht would be sufficient)
temperature or other gradient in your pond allowing separation of
levels, then I guess you would find a tritium gradient, and the rain
water being fresh, the diffrences should be a lot more measureable
than old aquifers. My 2c.

> Date:          Wed, 21 Feb 96 14:17:37 -0600
> Reply-to:      radsafe@romulus.ehs.uiuc.edu
> From:          Gary Schroeder <schroede@mail.sep.bnl.gov>
> To:            Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Subject:       Tritium stratification

> Does anyone know if it's possible for tritiated water to "stratify" if kept
> in a large pond which accepts ordinary rainwater?  We're talking about a
> total pond depth of approximately 7 ft. (pond is stagnant, artificial, and
> lined with plastic).  Everything tells me that the concentrations of tritium
> as sampled at any location within the pond should be completely homogeneous,
> but I have data which suggests otherwise.  Please e-mail directly with any
> insights you may have.
> ===============
> Gary L. Schroeder
> Brookhaven National Laboratory
> schroede@mail.sep.bnl.gov
>