Fwd: Legislation in relation to mineral sands

["Thatcher, Drew" <dht0303@hub.doh.wa.gov>]

                  ***** Original Message Follows *****


Dear Radsafers

I would like to ask you to direct me in obtaining any information in   
relation to different contries' legislation in relation to mineral sands; 
  
namely: ZIRCON, RUTILE and ILMENITE.  The mineral monazite usually   
present in mineral sands contain about 6% thorium and some uranium and,   

therefore, radiation monitoring programs were designed to monitor a   
possible exposure of workers and members of the public.

ZIRCON, RUTILE and ILMENITE contain thorium and uranium in concentrations 
  
incomparable with monazite and, therefore, as a separate minerals, were   

not a subject for any significant radiation protection programs in   
Australia.

However, the proposed limit for TENORM (Techncally Enhanced Naturally   
Occurring Radioactive Materials) of 5 pCi/g (CRCPD:   
http//www.webpub.com/~crcpd/) can potentially lead to classification of   

ZIRCON, RUTILE and ILMENITE as 'radioactive materials'.

Any information that can be obtained on radon emanation rates from   
mineral sands, information on the lack (or presence) of significant   
health hazards associated with NORM from Zircon for members of the public 
  
and workers, and information of disposal of zircon in land fills will be  
 
very useful.

Thank you

Nick Tsurikov,
Radiation Safety Officer - RGC Mineral Sands Limited
P.O. Box 47
Eneabba, WA 6518
AUSTRALIA
ph: +61 08 9956 9555
fax: +61 08 9956 9597

e-mail:   ntsuriko@rgc.com.au

(Those views are mine only, not those of my employer)

-=-=-=-=-=-
The origin of a majority of zircon sands in the US comes from Florida.  
However, through its use, both the states of Oregon and Washington (that 
I am aware of) have reveiwed the potential health aspects of zircon sands 
in relation to its use in parts casting.  I believe the State of Oregon 
legislatively exempted zircon sands with less than a given NORM activity, 
thereby allowing RCRA D landfill disposal (public landfill)  A good 
article on the sands is Boothe, G.F., HPS, vol 38.  The State of 
Washington determined that the zircon sands were acceptable for disposal 
in a public landfill due to the low radon emanation rate from the 
insoluble zircon sands.  A paper I reviewed from Rogers and Associates 
Engineering Corp estimated the emanation rates to be .015/.013 for 
Ra-226/Ra-228.   This is about a factor of 70 less than is commonly used. 
 I was unable to find a specific solubility product (when I looked at 
this issue) for the zircon but estimated it to be in the range of E-11 to 
E-20.  Activity for the sands analyzed were in the range of 1.5 Bq/g for 
the uranium series and 0.3 Bq/g for the thorium series.

I wrote a short paper (unpublished) analyzing the public health and 
worker aspects of disposing of the sands in a public landfill for a 
specific application in the state of Washington.  Let me know if you 
would like a copy of the paper.

Sincerely,
Andrew H. Thatcher, MSHP, CHP
Washington Department of Health
360-586-8715 voice
360-753-1496 fax
dht0303@hub.doh.wa.gov