Interim guidance for the safe transport of

Transcription

1 IAEA-TECDOC-750 Interim guidance for the safe transport of reprocessed uranium INTERNATIONAL ATOMIC ENERGY AGENCY

2 The IAEA does not normally maintain stocks of reports in this series. However, microfiche copies of these reports can be obtained from INIS Clearinghouse International Atomic Energy Agency Wagramerstrasse

3

4 Increasingly reprocessed uranium FOREWORD

5 EDITORIAL NOTE In preparing this document for press, staff of the IAEA have made up the pages from the original manuscript(s).

6 CONTENTS 1. INTRODUCTION...

7 APPENDIX

8 Application 1. INTRODUCTION

9

10 TABLE I. THE PHYSICAL PROPERTIES OF REPROCESSED URANIUM Chemical form (molecular formula) Physical state during transport Soluble/ insoluble Fractional uranium content (w/w) Uranium trioxide U0 3 solid moderately soluble U/U0 3 0,832 Uranyl nitrate U0 2 (N0 3 ) 2 solid/liquid soluble U/UO 2 (NO 3 ) 2.nH 2 O a Uranium tetra-fluoride solid moderately soluble U/UF UF 4 Uranium hexafluoride solid soluble U/UF UF 6 Uranyl fluoride U0 2 F 2 solid soluble U/U0 2 F Uranium dioxide UO 2 solid insoluble U/UO Tri-uranium octoxide U solid insoluble U/U 3 O a Generally, the water of crystallization in the solid is n = 6, and so the uranium content is in that form.

11 3. DEFINITION OF UNIRRADIATED URANIUM

12

13 Reprocessed uranium classified as LSA-II LSA-II is defined as follows in the current Regulations: "131. Low specific activity (LSA) material shall mean radioactive material which by

14 surrounding

15 transport

16 is primarily because

17 Package inspection to the requirements specified in para. 402 of the Regulations should

18 5. SUMMARY The consultants services meetings have examined the transport of reprocessed uranium

19 (b) When 10 mg of reprocessed uranium material contains in radioactivity less than

20 Appendix

21 Appendix II NUCLIDES COMPOSING REPROCESSED URANIUM Uranium compounds such as UF

22 to TABLE IV. CHARACTERISTICS OF REPROCESSED URANIUM PACKAGE Enriched uranium of natural source Enrichment A 2 (Bq) Item U 5% Unlimited Quantity equivalent of A 2 (kg) Activity (Bq/g) Activity limit of LSA-II (10%/B) Activity limit of LSA-III (2 X 10' 3 A 2 /g) Unlimited

23 Appendix in IAEA REGULATIONS CONCERNING REPROCESSED URANIUM This appendix summarizes those standards specified

24

25 Appendix

26 (2) UK proposal: Pu, FP, 236 U Whilst chemical purification techniques

27

28 Attachment

29 PROBLEMS Attachment 2 to Appendix IV

30

31 lower specific activity than

32 Appendix V REPROCESSED URANIUM CLASSIFIED AS LSA-II Reprocessed uranium can be classified as LSA-II in the following cases:

33 "AI.4.3.

34 TABLE

35 Appendix

36 (U) Samples U0 2, U powder U(%), O/U 3, F(ppm),

37 TABLE VIII. LEACHING TEST RESULTS

38 Attachment

39 Attachment

40 TREATMENT Appendix VII

41 requires further regulation under LSA-III

42 Appendix VIII A 2 OF MIXTURE TABLE IX. EXAMPLE OF CALCULATING A 2 VALUE (MIXTURE) 3 Uranium isotopes Content ratio of reprocessed uranium az U 234 u 235JJ 236 U Z38JJ Z28 Th

43 A Appendix IX

44 ê TABLE X. THE RELATION BETWEEN URANIUM ENRICHMENT AND A 2 VALUES Uranium isotopes A 2 (i) [Bq] 232 U 3 x 10 s 228 Th< 234 U 235 U 236 U 238 U "Tc Total A 2 value Remarks

45 TABLE

46 Appendix

47 TABLE XIII. EXTENT OF CONTRIBUTION OF RADIOACTIVE IMPURITIES AS A WHOLE TO THE VALUE OF A 2 (TEST CALCULATION WITH ENRICHED REPROCESSED URANIUM) (a) All nuclides taken into account Nuicl ides a o^

48 (b) Only representative nucl ides evaluated

49 DAUGHTER NUCLIDES Appendix XI

50 TABLE

51 Appendix XII CLASSIFICATION OF AN EMPTY CYLINDER CONTAINING UF

52 Since the specific activity under 1 is greater than that under 2 the transported item does not satisfy the standard for LSA-II. Alternatively, to qualify for a Type A transport, the total activity must

53 INVESTIGATIONS Annex

54 Abstract The

55

56 2. MODELLING FOR APPLYING THE ISOSHLD-PROGRAMME

57 FIG.

58

59 TABLE

60 1000 f 100 As

61 year 4 years years 16 years FIG.

62 O) u crö 20 nsv/h SO lisv/h distance

63 Öl o crö +-> i/l "O FIG. 13. Vector l, container drained, time: 1 year. FIG. 14. Vector 2, container drained, time: years. 69

64 FIG.

65 10000 vector! vector 2 vector 3 vector 4 FIG.

66 10000 vector 1 vector 2 vectors vector 4 FIG. 19. Comparison of surface dose rates of the drained container after years. 72

67 REFERENCES [1] INTERNATIONAL ATOMIC ENERGY AGENCY, Regulations for the Safe Transport of Radioactive Material, Safety Series No. 6, 1985 Edition (As Amended 1990), IAEA, Vienna (1990). [2] INTERNATIONAL ATOMIC ENERGY AGENCY, Explanatory Material for the IAEA Regulations for the Safe Transport of Radioactive Material (1985 Edition), Second Edition (As Amended 1990), Safety Series No. 7, IAEA, Vienna (1990).

68 CONTRIBUTORS TO DRAFTING AND REVIEW Consultants Services Meeting, Vienna,