1. RADIUM CONTROL IN URANIUM MINING WITH A SELECTIVE COMPLEXER Wayne Laughlin Bob Goltz The Dow Chemical Company

2. Historical Approaches to Radium Ra is a divalent cation; removed by water softener + Effective in removing Ra - Cost of salt, disposal of Ra brine Precipitation with BaSO4 + Effective in removing Ra - Requires sedimentation time and volume - Unknown cost at the end of the project

3. Selective Radium Complexer Precipitate of BaSO4 crystals inside of IX beads >8% wt/wt BaSO4 content Excellent Ra removal High capacity - Hundreds of nCi Ra/gram media Excellent flow properties Minimized volume of waste Confined and controlled

4. Photo of the beads

5. TEM of BaSO4 in beads

6. Radium Removal Typical flow rate of 10 gpm/ft2 Used to remove Ra from drinking water Cleaning

7. Excellent Flow Properties Beads are easily confined by screens in a column

8. Loading Capacity Hundreds of nCi/gram of media Since this is a precipitation mechanism, the loading capacity can be weight % levels Translates into millions of volumes of water treated per volume of media Need to run a projection to size a treatment system

9. Selective Radium Removal Media Excellent Ra removal High capacity Easy to use Minimized volume of waste Confined and controlled Known cost of use

10. References See our web site at www.TraceContaminants.comwww.TraceContaminants.com “Radium removal form Canadian uranium mining effluents by a radium-selective ion exchange complexer” L.A. Melis, Melis Consulting Engineers Ltd., Metallurgical Society of CIM, Vol 78, No. 883, pp 82-90 1985. “Removing and disposing of radium from well water” K.A. Mangelson and R. P. Lauch, Journal AWWA, June 1990, p 72-76.