Re: radium disposal

["Frank "Free Spirit" Borger" <frank@rover.bsd.uchicago.edu>]

> Date:          Mon, 6 Jan 97 08:32:37 -0600
> Reply-to:      radsafe@romulus.ehs.uiuc.edu
> From:          Lester.Slaback@nist.gov
> To:            Multiple recipients of list <radsafe@romulus.ehs.uiuc.edu>
> Subject:       radium disposal

> >No doubt:
> >Ra-226,  greatest headache . Geological repository is necessary... but
> >such a repository does not yet exist anywhere in the world...and probably
> >will not be in operation for some decades.
> 
> Ocean concentration : .05 pCi/L  (from Kathren)
> Ocean volume (a guess): 4 e+18 L
> Total est. activity: 1E5 Ci

	From the Encyclopedia Britannica (on-line version)

	Ocean area 		362x10^6 sq km
	average depth	3.7 km

	volume = 1.339 x 10^9 cubic km
	             = 1.339 x 10^18 cubic meters

	using a slightly fudged figure of 1000 liters per cubic meter

	volume = 1.339 x 10^21 liters 

	total Ra =  .05 x 10-12 oCi/l x 1.339 x 10^21 l 
	total Ra = 0.670 x 10^8 Ci

	Hmmm. Can anyone quote concentrations of Uranium and Thorium? It might 
	be instructive to calculate total ocean activity for lets say 10^6 cu km and 
	compare that  to  the recent Pu that landed in the Pacific.

Frank R. Borger - Physicist - Center for Radiation Therapy
net: Frank@rover.uchicago.edu   ph: 312-791-8075 fa: 791-3697

Have you heard of the ship called the good Reuben James
manned by bold fighting men, both of honor and of fame.
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But tonight She's in her grave, at the bottom of the sea.
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