[ RadSafe ] Fw: Uranium contamination

[Dan W McCarn]

Dear Group:

OK, I'll step in on this one!  About 1/4 of the US is directly underlain
with uranium-bearing soils and rock, specifically those underlain by the
Chattanooga Shale, Pierre Shale or Mancos Shale.  Typical concentrations of
uranium in these marine black shales are 80-120 ppm or about 0.01% U.
Phosphorites also contain significant uranium at about the same
concentration.  Florida has abundant occurrences / deposits of uraniferous
marine phosphorites.

That being said, the uranium in these rocks are fairly tightly bound
organically.  Uranium which might occur in other rock types would tend to
lose uranium fairly quickly on exposure to meteoric conditions except under
certain conditions (availability of vanadium).

We had a discussion about this subject two or three years ago including
calculations for the "English Garden".  I did a recalculation for
Chattanooga shale soils about that time.

There are other modes of reconcentration in soils including pedogenic
calcretes which tend to concentrate U by evaporative pumping in the desert
SW. Also called hardpan, duricrusts, pedocretes and caliche, they can be
formed from silica (silcretes), calcium carbonate (calcretes), or gypsum
(gypcretes).  The Ogallala Fm from Texas to the Dakotas contains uraniferous
pedogenic silcretes.

That doesn't answer your question, but perhaps covers some of the ranges of
soil concentrations associated with a common rock type.

Dan ii

--
Dan W McCarn, Geologist
2867 A Fuego Sagrado
Santa Fe, NM 87505
+1-505-310-3922 (Mobile - New Mexico)
HotGreenChile at gmail.com (Private email)

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Jerry Cohen
Sent: Wednesday, March 24, 2010 15:06
To: Miller, Mark L; radsafe at health.phys.iit.edu
Subject: Re: [ RadSafe ] Fw: Uranium contamination

Can anyone suggest any reasonable set of conditions where soil contamination
with uranium might constitute a credible threat to health and safety ?
Jerry Cohen 

PS: It is now springtime, or as Al Gore suggests,  "Proof of global warming"



________________________________
From: "Miller, Mark L" <mmiller at sandia.gov>
To: Jerry Cohen <jjcohen at prodigy.net>
Sent: Wed, March 24, 2010 10:16:53 AM
Subject: RE: [ RadSafe ] Fw:  Uranium  contamination

As with everything, the answer is, "It depends."  A pathway analysis (like
RESRAD) can tell you if a problem exists, it's magnitude and the most likely
pathway(s) of exposure.  The devil's in the dose.  Armed with that, you can
THEN ask, "Now what"?  The "what" might be "no action" or appropriately
targeted action.

-----Original Message-----
From: Jerry Cohen [mailto:jjc105 at yahoo.com] 
Sent: Tuesday, March 23, 2010 4:24 PM
To: radsafe at health.phys.iit.edu
Subject: [ RadSafe ] Fw: Uranium contamination


Does the existence of Uranium contamination in soil constitute a credible
threat to heath and safety, or is this just another costly federal
"feel-good" program? If such uranium contamination is really a problem, what
should be done with the millions of tons of uranium in the oceanic coastal
waters. We even are allowing children to swim in it. 
Jerry Cohen
________________________________
From: Cary Renquist <cary.renquist at ezag.com>
To: radsafe at health.phys.iit.edu
Sent: Fri, March 19, 2010 6:10:01 PM
Subject: [ RadSafe ] Argonne scientists seek natural remediation for
uranium-rich sites

They are looking to understand and optimize the conditions under which
bacteria can 
transform U(IV) <soluble> to U(VI) <insoluble>

Argonne scientists seek natural remediation for uranium-rich sites 
Link  http://j.mp/b3AHAh
Cary
-- 
Cary.renquist at ezag.com
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