1. The Determination Of 226 Ra In Soil Samples Lawrence D. Morris General Engineering Laboratories, Inc. Anil H. Thakkar Eichrom Technologies, Inc.

2. General Engineering Laboratories, Inc. Charleston, SC Objective: Design a reliable method to measure 226 Ra in soil samples by Alpha Spectroscopy thus meeting the current need of our clients.  Faster Turn Around Times than current methods  This procedure utilizes Cation and Eichrom’s Ln Resin  Achieve Peak Resolution (FWHM) of less than 100keV

3. General Engineering Laboratories, Inc. Charleston, SC Anil Thakkar visited GEL in April  Discussed the Radium in Water procedure –Ran some test samples

4. General Engineering Laboratories, Inc. Charleston, SC Spectrum from Testing Water Procedure

5. General Engineering Laboratories, Inc. Charleston, SC  This brought up the question about how well the procedure would work with soils? Spectrum from Testing Water Procedure

6. General Engineering Laboratories, Inc. Charleston, SC Highlights of the Procedure: Radium in Water (RAW03) Eichrom Technologies, Inc.  Digest the sample  Dissolve the residue with dilute HNO 3  Pass sample through Cation resin column  Elute Ra and Ba with 8M HNO 3  Evaporate eluate to dryness  Dissolve residue with 0.095M HNO 3

7. General Engineering Laboratories, Inc. Charleston, SC  Pass through Ln Column collecting the eluate for determination of 226 Ra  Perform Barium Sulfate micro-precipitation  Filter  Count on Gamma for Tracer Recovery ( 133 Ba)  Count on Alpha for 226 Ra determination Highlights of the Procedure: Radium in Water (RAW03) Eichrom Technologies, Inc.

8. General Engineering Laboratories, Inc. Charleston, SC Test #1 Results SampleVolume (g) % Yield ( 133 Ba) Activity (pCi/g) Uncertainty 2-Sigma (pCi/g) MDA (pCi/g) FWHM (keV) % Recovery 1 (Sample) 1.0196.63.700.410.05142 2 (Sample) 0.59101.13.560.460.07172 3 (Sample) 1.0792.63.550.400.04417 4 (Blank) 1.0098.2-0.010.020.073 5 (Matrix Spike) 0.5898.821.201.820.0930092.6 6 (Lab Control Sample) 1.00100.611.000.950.0580100.9

9. General Engineering Laboratories, Inc. Charleston, SC Test #1 Spectra Sample 1

10. General Engineering Laboratories, Inc. Charleston, SC Test #1 Spectra Sample 3

11. General Engineering Laboratories, Inc. Charleston, SC Test #1 Spectra Sample 6 (LCS)

12. General Engineering Laboratories, Inc. Charleston, SC Problem with initial testing:  Resolution exceeded 100keV –Suspected cause was from natural Barium in the soil.

13. General Engineering Laboratories, Inc. Charleston, SC Proposed solutions: Use less sample Use less Barium Carrier –100  L of 0.75 mg/mL Barium Carrier was used for Test #1 Use less Seeding Suspension

14. General Engineering Laboratories, Inc. Charleston, SC Test #2  Analyze 3 samples with No Barium Carrier  Analyze 3 samples with 50  L of Barium Carrier  Vary aliquot size from 0.1g to 0.5g

15. General Engineering Laboratories, Inc. Charleston, SC Test #2 Results SampleVolume (g) % Yield ( 133 Ba) Activity (pCi/g) Uncertainty 2-Sigma (pCi/g) MDA (pCi/g) FWHM (keV) 1 No Barium 0.4793.23.840.080.09177 2 No Barium 0.2599.14.040.430.06105 3 No Barium 0.1692.53.680.550.1596 4 50µL Barium 0.4897.93.790.360.01129 5 50µL Barium 0.2595.43.780.440.12172 6 50µL Barium 0.1096.63.850.580.26104

16. General Engineering Laboratories, Inc. Charleston, SC Problem with Test #2:  Resolution on samples with reduced Barium Carrier continue to exceed 100keV

17. General Engineering Laboratories, Inc. Charleston, SC Test #2 Spectra Sample 1

18. General Engineering Laboratories, Inc. Charleston, SC Test #2 Spectra Sample 3

19. General Engineering Laboratories, Inc. Charleston, SC Test #3  Used 0.1mL of the seeding suspension 0.2mL used previously  No Barium Carrier was used

20. General Engineering Laboratories, Inc. Charleston, SC Test #3  No Barium Yields FAILURE

21. General Engineering Laboratories, Inc. Charleston, SC Test #4  Comparison of Alpha Spec vs. Emanation  Alpha Spec –Used 0.2g of sample –50  L of Barium Carrier  Emanation used 0.5g of sample

22. General Engineering Laboratories, Inc. Charleston, SC Test #4 Results SampleVolume (g) % Yield ( 133 Ba) Activity (pCi/g) Uncertainty 2-Sigma (pCi/g) MDA (pCi/g) FWHM (keV) Alpha Spec Run 10.2061.75.041.120.48172 20.2045.53.311.080.6099 Emanation Run 10.514.250.840.31 20.514.530.960.59

23. General Engineering Laboratories, Inc. Charleston, SC Test #4 Spectra Sample 1

24. General Engineering Laboratories, Inc. Charleston, SC Test #4 Spectra Sample 2

25. General Engineering Laboratories, Inc. Charleston, SC Update to the Objective  Further discussions with the client revealed they were never able to achieve resolution <100keV –They re-set their requirement to <250keV  Current testing Average FWHM –149keV –Consistently <200keV

26. General Engineering Laboratories, Inc. Charleston, SC Changes to 226 Ra Water Procedure  Ensure that 0.5g or less of soil used –Minimizes natural Barium introduced  Reduce Barium carrier used –50µL 0.75mg/mL

27. General Engineering Laboratories, Inc. Charleston, SC In Conclusion  Original FWHM Goal (<100keV) not achieved –Client changed their requirement to <250keV Average FWHM for soils 149keV  Faster Turn Around Times accomplished –Soils can be run in 2 days Emanation 3 day minimum Gamma 7-30 day minimum –Waters can be run in 1 day