Contaminated casks

["RONALD L. SHEPHERD" <SHEPHRL@GWSMTP.NU.COM>]

Dr. Feinhals

We had a similar situation here in the states some time ago.  The problem was
that the casks were left in the water too long and the contaminates migrated
into the surface pores of the metal.  Even though the surfaces were wiped down
and smears indicated a clean surface, the transport time was sufficient to
allow the contaminates to leech out of the metal and it showed up at the burial
site as a contaminated cask per their surveys.

Our approach to this was four fold:
1.  Decon the cask repeatedly over a two week period so that most all of the
contaminates could leech out and be cleaned.

2.  Prior to immersion in the contaminated pool water we would continuously
spray the cask from all sides to ensure a protective film of water that would
help keep the contaminates from rushing into the pores of the metal.

3.  Limit the time the cask is allowed to stay in the pool.

4.  Spraying the cask down as it is being removed from the water and an
immediate wipe down with demineralized water removed any lingering surface
contamination prior to shipment ( do not allow it to air dry before this wipe
down ).

Following these steps allowed us to make repeated shipments without any
problems of contamination events at the burial site.

Hope this helps.  Any other questions I can be reached at

shephrl@gwsmtp.nu.com

Ron Shepherd
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