Re: Cleanup standards

["Jerry Cohen" <jjcohen@PRODIGY.NET>]

The difficulty in cleaning up of Cs-137 contaminated areas depends entirely

on the standards applied to determine adequacy. For cleanup to the point

where occupancy would be reasonably safe, Bernie is correct in assuming it

would be relatively easy. BUT, if EPA standards were to apply [maximum

individual dose <15. mrem/a, as determined by a  scenario that includes

compounding  worst case exposure assumptions] cleanup would be nearly

impossible. For example, we are still paying megabucks for cleanup of

Cs-137 residual contamination at Bikini and other

Marshall Islands from bomb tests that occurred over 50 years ago.



----- Original Message -----

From: John Andrews <andrewsjp@chartertn.net>

To: BERNARD L COHEN <blc+@PITT.EDU>

Cc: internet RADSAFE <radsafe@list.vanderbilt.edu>

Sent: Thursday, February 27, 2003 5:34 PM

Subject: Re: Dirty bombs





> BERNARD L COHEN wrote:

>

> > Can someone explain why dispersed CsCl in a city is a long term

> >hazard? Isn't it highly soluble in water? If so, it should be easy to

hose

> >away, using radiation detectors to locate hot spots. The water with CsCl

> >would go into the sewer system. Even without hosing, rain should wash

away

> >most of it.

> >

> >Bernard L. Cohen

> >Physics Dept.

> >University of Pittsburgh

> >Pittsburgh, PA 15260

> >Tel: (412)624-9245

> >Fax: (412)624-9163

> >e-mail: blc@pitt.edu

> >

> >

> >

> I cleaned up an old spill of Cs-137 once.  The material had been cleaned

> up years earlier, but residual material remained on some of the

> concrete.  It had penetrated into the concrete up to one inch in

> discrete spots.  This indicated to me that actual grains of the spilled

> source material remained on the concrete and the cesium was sorbed by

> whatever reaction into the concrete.  There was low level general

> contamination just above backround in adjacent areas indicating

> migration from the hot spots.  Effective cleaning included jackhammering

> or intense needle-gun decon of the spots and scabbling the general areas

> to 1/2 inch.

>

> I would expect the same from any Cs-137 spill.

>

> John Andrews

> Knoxville, Tennessee

>

> ************************************************************************

> You are currently subscribed to the Radsafe mailing list. To unsubscribe,

> send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

> radsafe" (no quote marks) in the body of the e-mail, with no subject line.

> You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/





************************************************************************

You are currently subscribed to the Radsafe mailing list. To unsubscribe,

send an e-mail to Majordomo@list.vanderbilt.edu  Put the text "unsubscribe

radsafe" (no quote marks) in the body of the e-mail, with no subject line.

You can view the Radsafe archives at http://www.vanderbilt.edu/radsafe/