RE: Uranium mill tailings

[Bill_Goldsmith@radian.com]

Barbara: This is a very general answer to your question based on my archaic
knowledge.  K-65 residues resulted from the Mallinckrodt processing of
pitchblende ore to remove the uranium in a Manhattan Engineer District
project.  The ore was ground and digested with nitric acid which dissolved
the uranium and a number of other elements, principal among which was
radium.  At that time, radium had a high economic value.  Barium carbonate
was added to the leach solution to precipitate barium, radium, and sulfate
ions.  Uranium was extracted from the leach solution using ether.  The
precipitate cakes became the K-65 residues.  The richness of the ore and the
efficiency of the process resulted in concentrations of Ra-226 in the tens
of nanocuries per gram of residue (or higher).  In addition to the problems
of generating Rn-222, the gamma radiation presented an external exposure
problem during handling operations.  The K-65 residues were transferred to a
water tower at the Niagara Falls Storage Site and a silo at Fernald.
Similar residues were produced at Fernald and stored in another silo there.
Residues at Niagara Falls were transferred to a subsurface disposal cell at
that site in the early 1980s.  The final chapter of Fernald residues will be
written when the CERCLA actions there are complete.  
Hope this helps.

Bill_goldsmith@radian.com <mailto:Bill_goldsmith@radian.com> 

		-----Original Message-----
		From:	BLHamrick@aol.com [mailto:BLHamrick@aol.com]
		Sent:	May 05, 1999 21:19
		To:	Multiple recipients of list
		Subject:	Re: Uranium mill tailings

		What are the K-65 residues?  Or, am I going to be totally
sorry I asked?

		Barbara Hamrick
		BLHamrick@aol.com
	
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