National Radiation Protection Authority protecting people and the

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Applying Nuclear Forensics in Nuclear Material Accounting and Control of Radioactive Material out of Regulatory Control from a Facility Vera Uushonaa & Manny Mathuthub a. National b. Centre Radiation Protection Authority, Namibia for Applied Radiation Science and Technology (CARST) North-West University (Mafikeng Campus), 1

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Outline Introduction Aims & Objectives Results and Conclusions 2

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation What is Nuclear Forensics? Illicit trafficking of nuclear material has led to the emergence of a new discipline of science called Nuclear forensics is the examination of nuclear or other radioactive materials, or of evidence contaminated with radionuclides, in the context of legal proceedings under international or national law related to nuclear security ü The goal of forensic science is to discover linkages among people, places, things and events 3

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Nuclear Forensics in Nuclear Security • • • Nuclear forensics is one component in an on-going national programme for nuclear security. It supports both the prevention of and the response to a nuclear security event. An effective national nuclear security infrastructure is vital to ensure that nuclear and other radioactive material does not fall into the wrong hands. e ecut Pros rn Retu Item e ibut Attr lyze Ana nce e Evid ect Prot ce en Evid age Man e Crim e Scen rdict Detection Inte t ss Asse lert m/A Alar c Dete ss Asse t a Thre ect. Prot re Secu r. Dete ade u Diss Prevention Response 4

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Nuclear Forensics signatures • Signatures are characteristics, or combinations of characteristics, that help to answer investigative questions • Signatures are used to trace the origin and intent of the interdicted nuclear material. • Nuclear Forensics signatures include Age Dat e ü Isotope composition ü Major elements ü Trace elements ion osit p m c co opi t o ü Physical Properties Is ü Morphology ü Age date Conceptual diagram – ts le E or en m aj M s sic al” n itio rad en for “T Ph ys ica lp rop ert ies forensic signatures 5

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Uranium Minning • At Each stage signatures are destroyed and created (MURD, 2019) Ø In Namibia there is a vast uranium ore (uraninite) deposits activities mainly concentrated in the Erongo Region (NAP, 2012) 6

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Aim and Objectives The aim of the study to determine nuclear forensics signatures for uranium bearing materials in Namibia Objectives To characterise Uranium bearing material in terms • Impurities • Lead Isotopic Ratios • Age determination • REE • Morphology 7

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Methodology Samples Uranium Bearing Materials ( Tailings recovery water, UOC) Pb, Age determination, REE Morphology Used SEM Used ICPMS for analysis FEI Quanta 250 FEG Perkin Elmer Nex. ION 2000 ICP-MS 8

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Results: Impurities Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Sample 8 Sample 9 Sample 10 Average STDEV min max Table 1 Sr** Concentration Tailings Water (µgl-1) (n = 3) *U **As **Cr ***K 0. 00848 145. 68 3. 1593 0. 03846 0. 01255 155. 07 3. 22962 0. 0411 0. 02918 186. 78 3. 57992 0. 03827 0. 03685 200. 89 4. 05696 0. 0492 0. 0406 214. 21 4. 14588 0. 04577 0. 04005 220. 46 4. 15335 0. 04854 0. 04134 226. 96 4. 18537 0. 05928 0. 04254 231. 98 3. 99859 0. 04334 0. 04366 235. 77 3. 97821 0. 04747 0. 04152 0. 0337 0. 0129 0. 0085 0. 0437 239. 25 205. 7057 33. 3495 145. 6821 239. 2548 3. 96011 3. 8447 0. 3830 3. 1593 4. 1854 0. 04993 0. 04614 0. 00631 0. 03827 0. 05928 0. 00002 0. 00003 0. 00005 0. 00007 0. 00005 0. 00003 0. 00004 0. 00003 0. 00002 0. 00000 0. 00007 **Th 0. 0124 0. 01328 * Major ** Minor *** Trace level 0. 01522 0. 01658 0. 01738 0. 01796 0. 01862 0. 01878 0. 01925 0. 01688 0. 00248 0. 01240 0. 01928 9

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation RESULTS: Pb isotopic Ratios and Age Determination Figure 1: Nuclear forensic signature from the lead isotopic ratios for Mine A (tailings recovery water) Figure 2: Age determined from 207 Pb/206 Pb using the Isoplot code estimated at 4741 Ga yrs (tailings recovery water)

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation RESULTS: REE Patterns (Signatures) q REE patterns show fractionation of the HREE q LREE are heavily depleted Fig 2: REE Pattern 11

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation RESULTS: SEM Morphology Fig 3: Mine A Particles are spherical and appears homogenous and agglomerated Fig 3: Mine B Plate like structures with small spherical particles 12

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation Conclusion Analyzing the recovery process water gives distinct indicators of impurities that are in the uranium bearing material Four different nuclear forensics signatures could be clearly resolved by ICP-MS, viz: impurities, REE patterns, Pb isotopic ratio and the age of the samples. SEM revealed difference in the structure 13

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation ACKNOWLEDGEMETS We would like to acknowledge the: v International Atomic Energy Agency (IAEA), in Austria, for sponsoring the 2019 Nuclear Forensics Project under CRP J 23100, Grant # J 23100/R 0. 14

National Radiation Protection Authority protecting people and the environment against the harmful effects of radiation 15