GENERATION IV PLUTONIUM PROLIFERATION RISKS

1. GENERATION IVPLUTONIUM & PROLIFERATION RISKS Steven C. Sholly 8 November 2007 Presented at: Science or Fiction: Is There a Future for Nuclear?

2. GEN. IV DESIGNS Gas-cooled reactor (VHTR)? Water-cooled reactor (SCWR)? Non-Breeder Fast Reactors (Breeding Ratio = 1)? Gas-cooled fast reactor (GFR)? Lead-cooled fast reactor (LFR Sodium-cooled fast reactor (SFR)? Breeder � Molten salt reactor (MSR)?

3. CURRENT LEVEL OF DESIGN DETAIL VHTR � moderate to minimal SCWR � minimal GFR � minimal LFR � almost nonexistent SFR � almost nonexistent MSR � nonexistent (the U.S. is not pursuing this design)?

4. GOAL OF GEN. IV FOR NON-PROLIFERATION Generation IV nuclear energy systems are "exceptionally proliferation resistant" (emphasis added)? This certainly implies an improvement over the current situation with LWRs, PHWRs and LMRs

5. NONPROLIFERATION STUDY SCHEDULES (DOE)? Methdological framework & demonstration application by 2009 Application to Generation IV reactors from 2009-2017 From 2007-2009 � speculation and vague promises

6. VHTR

7. AREVA ANTARES VHTR http://www.areva-np.com/scripts/info/publigen/content/templates/show.asp?P=1559&L=US&SYNC=Yhttp://www.areva-np.com/scripts/info/publigen/content/templates/show.asp?P=1559&L=US&SYNC=Y

8. VHTR Highest priority for the US (for hydrogen production, NGNP)? Medium-term prospect Planned by US as once-through fuel cycle (GT-MHR, H2-MHR, PBMR)? GT-MHR planned by Russia for weapons-grade plutonium burning mission (GT-MHR)? Technology choices necessary (prismatic core vs. pebble bed core; gas-cooled vs. molten salt-cooled)?

9. VHTR ANTARES - 1 AREVA working on ANTARES VHTR (AREVA New Technology based on Advanced gas-cooled Reactors for Energy Supply)? Primary circuit is an evolution of the GT-MHR; prismatic core, He-cooled Secondary cycle is an indirect combined cycle gas turbine incorporating a nitrogen-based Brayton cycle with s Rankine bottoming cycle (300 MWe plus process heat)? http://www.iaea.org/inis/aws/htgr/fulltext/htr2004_a10.pdf AREVA ANTARES Brochure (2005), http://www.areva-np.com/common/liblocal/docs/Brochure/VHTR_A_2005.pdf AREVA ANTARES VHTR Process Heat Brochure (2006), http://www.areva-np.com/common/liblocal/docs/Brochure/VHTRadd_A_2006.pdfhttp://www.iaea.org/inis/aws/htgr/fulltext/htr2004_a10.pdf AREVA ANTARES Brochure (2005), http://www.areva-np.com/common/liblocal/docs/Brochure/VHTR_A_2005.pdf AREVA ANTARES VHTR Process Heat Brochure (2006), http://www.areva-np.com/common/liblocal/docs/Brochure/VHTRadd_A_2006.pdf

10. VHTR ANTARES - 2 Fuel is TRISO-coated 14% enriched uranium (either oxide or oxycarbide)? Refueling every 18 months (550 EFPD)? Avg. burnup 150 GWd/tHM 50% of the core is replaced (510 elements)? In 60-year plant life, 20,000 spent fuel elements (1770 m3) and 10,000 graphite reflector blocks (840 m3) expected to be generated At discharge, spent fuel contains 8-9% enriched uranium http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b02.pdf http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b05.pdf http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b02.pdf http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b05.pdf

11. VHTR ANTARES - 3 Fuel particles separated from graphite using proprietary process (yet to be developed)? Once separated, uranium is reprocessed using PUREX process

12. PBMR - 1 PBMR is a modular, pebble bed HTGR design, 400 MWt/165 MWe Pebbles are 60 mm diameter, with 0.5 mm UO2 fuel kernal containing 9 grams heavy metal Core contains 452,000 pebbles Refueling done online (489 fresh pebbles and 2936 recirculated pebbles/day)? http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b14.pdfhttp://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b14.pdf

13. PBMR - 2 Equilibrium fuel cycle, avg. residence time in core is 923 days Avg. burnup 90.8 GWd/tHM Plutonium-239 buildup per pebble � 1st pass 0.03g; 2nd thru 6th pass 0.042-0.044 (approx)? Pu-240, Pu-241 & Pu-242 steady buildup in 2nd thru 6th pass

14. PBMR - 3 Designer asserts that high fractions of Pu-240 thru Pu-242 "does not favour the production of a reliable nuclear explosive device" Designer asserts that heat generation by these isotopes "will cause rapid degradation of the high explosive components of such a device" http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b14.pdf http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b14.pdf

15. PBMR - 4 Designer asserts that it is "impossible to produce weapons grade plutonium in a target of U-238 because in a single pass the Pu-240 isotope is larger than 20% of the Pu-239" http://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b15.pdfhttp://www.iaea.org/programmes/inis/aws/htgr/fulltext/htr2004_b15.pdf

16. GT-MHR

17. GT-MHR Claims of designer: Spent fuel "self-protecting" (high radiation field and high spent fuel mass and volume)? Spent fuel diluted with graphite Pu isotopic pakeup "is degraded well beyond light water reactor spent fuel making it particularly unattractive for use in weapons" http://gt-mhr.ga.com/images/ANS.pdfhttp://gt-mhr.ga.com/images/ANS.pdf

18. NGNP - 1

19. NGNP - 2

20. NGNP - 3

21. SCWR

22. SCWR - 1 Medium-term prospect Thermal and fast spectrum options Thermal option is once-through fuel cycle; burnup typical of LWRs Fast spectrum option plans to use aqueous reprocessing (UREX+) and full actinide recycle Under investigation by 32 organizations in 13 countries (includes AECL, FzK, CEA, KAERI, INL, VTT, PSI, AREVA, Toshiba)? http://www.tkk.fi/Units/AES/courses/crspages/Tfy-56.181_03/Danielyan.pdf http://www.aecl.ca/Assets/Publications/Advisory+Panel/2004-RDAP.pdf http://neri.inel.gov/program_plans/pdfs/appendix_2.pdf http://www.tkk.fi/Units/AES/courses/crspages/Tfy-56.181_03/Danielyan.pdf http://www.aecl.ca/Assets/Publications/Advisory+Panel/2004-RDAP.pdf http://neri.inel.gov/program_plans/pdfs/appendix_2.pdf

23. SCWR � 2 Thermal efficiency of 44-45% vs. 33-36% for PWRs & BWRs (44% thermal efficiency achieved on coal-fired units)? No recirculation pumps, no pressurizer, no SGs, much smaller (pressure suppression) containment Over 450 supercritical water cooled coal-fired plants in operation AECL working on CANDU-SCWR concept (50% cheaper on capital & operating costs forecasted)? http://www.aecl.ca/Assets/Publications/Advisory+Panel/2004-RDAP.pdfhttp://www.aecl.ca/Assets/Publications/Advisory+Panel/2004-RDAP.pdf

24. SCWR - 3 CANDU-SCWR may pose typical CANDU problems (high reactor grade plutonium production plus tritium production), albeit at somewhat reduced rates (compared to CANDU-6 or ACR-1200) due to higher thermal efficiency Proliferation considerations of LWR-SCWR similar to PWRs Some consideration also given to fast reactor SCWR and VVER SCWR

25. GFR

26. LFR

27. SFR

28. GFR, LFR & SFR Long-term prospects Intended (by US) to burn actinides No net breeding of fuel (burners, breeding ratio < 1, GNEP; "converters" with breeding ratio ~ 1); if breeding ratio is not > 1, it's not a "breeder" US Gen. IV Fast Reactor Strategy (DOE/NE-0130, Dec 2006) http://www.ne.doe.gov/pdfFiles/genIvFastReactorRptToCongressDec2006.pdf All 3 capable of burner, converter & breeder modes of operation

29. GFR, LFR, SFR GFR � closed fuel cycle, onsite fuel cycle facilities LFR � closed fuel cycle, central or regional fuel cycle facilities SCR � two options 150-500 MWe with co-located pyrometallurgical reprocessing 500-1500 MWe with aqueous reprocessing (UREX+) at central facility

30. GFR � 1 Similar to GT-MHR (helium-cooled Brayton cycle); supercritical CO2 being considered as well Uranium-Plutonium carbide fuel, 20% Plutonium (final decision pending), no fertile blanket Burnup to 250 GWd/tHM 42% thermal efficiency Being worked on by CEA & AREVA (France), GA & INL (US)? No operating experience with GFRs (not even a prototype)? http://neri.inel.gov/program_plans/pdfs/appendix_3.pdf http://anes.fiu.edu/Pro/s9Kha.pdf http://neri.inel.gov/program_plans/pdfs/appendix_3.pdf http://anes.fiu.edu/Pro/s9Kha.pdf

31. GFR - 2 France plans < 50 MW Engineering Technology Demonstration Reactor (ETDR) by 2015 GFR demonstration reactor planned for 2025 Fuel for ETDR may be different from GFR Demo Not a breeder � breeding ratio = 1 (self-generating)? Projected $940 million GFR R&D budget

32. LFR - 1 Basic concept is 45 MWt/20 MWe "Small Secure Transportable Autonmous Reactor" (SSTAR)? Intended for developing nations and remote communities without grid connections No direct LFR experience; 80 reactor-years of lead-bismuth eutectic fast reactor experience (2 land-based and 10 naval reactors)? "Nuclear Battery" concept, 20-30 year sealed core http://neri.inel.gov/program_plans/pdfs/appendix_4.pdfhttp://neri.inel.gov/program_plans/pdfs/appendix_4.pdf

33. LFR - 2 Natural circulation primary, autonomous load following without control rod motion Supercritical CO2 Brayton cycle energy conversion system Transuranic nitride fuel (�100% N15 to eliminate C14 production)? Average discharge burnup of 72 GWD/tHM (peak of 120)? Operation of prototype by 2025

34. SFR - 1 2 design concepts (Japanese SFR, Korean KALIMER)? Japanese SFR 150-1500 MWe, KALIMER 600-1500 MWe Burnups 70-200 GWd/tHM and 66-150 GWd/tHM respectively Possible breeders (Japanese SFR conversion ratio of 0.5-1.2, KALIMER 1.0-1.2)? Oxide vs. metal fuel choices pending http://neri.inel.gov/program_plans/pdfs/appendix_5.pdfhttp://neri.inel.gov/program_plans/pdfs/appendix_5.pdf

35. SFR - 2 Oxide fuel would involve advanced aqueous reprocessing; metal fuel would involve pyroprocessing Pyroprocessing demonstrated at very small scale (50g of Pu)?

36. MSR

37. MSR - 1 Indefinitely delayed Very long-term prospect; not being pursued by the US, but is being pursued in Europe ("several tens of researchers" according to DOE)? European programme aimed at viability determination by 2013 Possible once-through Th-232/U-233 fuel cycle Gas-cooled, Brayton cycle turbine

38. MSR - 2 Limited experience (2.5 MWt Aircraft Reactor Experiment; 8 MWt MSRE)? Nothing known of economics Research by France (CEA), Czech Republic, and US (ORNL)? Very high burnup and Pu-242 fraction Possible use in Th-232/U-233 breeder fuel cycle

39. GENERATION IV INSIGHTS For Generation IV designs, one is primarily concerned about reactor-grade plutonium (no HEU fuel use envisioned)? SCWR spent fuel is as problematic as LWRs & CANDU � "exceptional" proliferation resistance? Gen. IV fast reactors and VHTR involve very high burnups, resulting in Plutonium isotope mixture that is poorly suited for weapons (compared with LWRs & CANDU)?

40. GENERATION IV CAVEATS - 1 In principle, problems of using RG Pu for a weapon can be overcome by tritium boosting Theft or diversion of reactor-grade plutonium likely to be accompanied by tritium theft for this reason Theft of tritium is a broad hint that reactor-grade plutonium has been stolen or diverted

41. GENERATION IV CAVEATS - 2 Note, however, that 3.5% enriched fuel already has about 80% of the SWU of enrichment done to take it to HEU Example: Consider an initial core for a 1000 MWe LWR, enriched to 3.5% If you take this uranium and make UF6 feed material, then 11,000 centrifuges can provide you with a 20 kg bomb core per week for almost a year, rejecting tails at 2% Uranium-235

42. GENERATION IV CAVEATS - 3 And you will still have 1700 kg of Uranium-235 in the tails that you can then more leisurely take to higher enrichment, rejecting at a lower tails assay The net result is something like 100 fission bomb cores for the �4 billion cost of a 1000 MWe LWR and first core (scrap the plant if you like, this is only �40 million per bomb core (assuming you have built the centrifuge enrichment plant anyway)? Obviously, starting at 5% or 10% or 19.9%, the process goes that much faster

43. NUCLEAR WEAPONS Six types can be distinguished: Nuclear fission weapon (gun type plus spherical, cylindrical & linear implosion)? Boosted nuclear fission weapon Enhanced radiation weapon ('Neutron bomb')? 'Sloika' ('Alarm Clock') multiple concentric shell boosted fission weapon Thermonuclear (radiation implosion) weapon Salted weapons ('doomsday bomb')?

44. WEAPONS USABLE MATERIALS Highly enriched uranium (HEU)? Uranium-233 Super-grade plutonium (Pu-239 typically 97% or higher)? Weapons-grade plutonium (Pu-239 typically 93% or greater)? Reactor-grade plutonium Neptunium-237 Americium-241 (impractical)?

45. WEAPONS USEFUL MATERIALS Tritium (boosting)? Lithium (especially Lithium-6) (fission-fusion-fission)? Depleted or natural uranium (tamper; fission-fusion-fission)? Beryllium (tamper)?

46. REACTOR-GRADE Pu Unquestionably weapons-usable More highly variable yield Greater tendency toward predetonation & fizzle or reduced yield However fizzle is 1 kt or greater for Nagasaki-type design � a fizzle yield is not a dud (the damage radius of 1 kt detonation is about one-third that for 10 kt)?

47. NEPTUNIUM-237 - 1 Unquestionably weapons-usable Even better than HEU (lower spontaneous neutron generation, higher likelihood of full yield)? Can be used in simple gun-type (Hiroshima) design All the advantages of HEU without the need for enrichment (available in spent fuel)?

48. NEPTUNIUM-237 - 2 Weapons usability of neptunium 237 established beyond reasonable doubt by experiment at Los Alamos National Laboratory in September 2002 Bare sphere critical mass estimated in the upper 50 to low 60 kg range (compared with 50 kg for HEU)? Typical 1000 MWe LWR produces 13 kg of Neptunium 237 per year (versus 100s of kilograms of Pu)?

49. GUN-TYPE DESIGN

50. SPHERICALIMPLOSION DESIGN - 1

51. SPHERICALIMPLOSION DESIGN - 2

52. SLOIKA WEAPONS - 1 Sloika (??????) weapons are arranged in multiple concentric layers around a fission pit or boosted fission pit Layering involves Lithium Deuteride (most effectively Lithium-6) and Tritium Sloika weapons have been tested by the former Soviet Union and the United Kingdom

53. SLOIKA WEAPONS - 2 Two Russian tests, one with tritium spiked Lithium-6 and a depleted uranium shell, the other without tritium spiking Yields were 400 kt and 250 kt These were, respectively, the 5th (12 August 1953) and 23rd (6 November 1955) tests

54. SLOIKA WEAPONS � 3 Two British Sloika tests, one using a depleted uranium shell and one using a highly enriched uranium shell Yields were 98 kt (DU shell) and 720 kt (HEU shell) These were, respectively, the 5th (Mosaic G2, 19 June 1956) and (Grapple 2/Orange Herald, 31 May 1957) 11th (31 May 1957) tests One source lists Grapple/Purple Granite (19 June 1957, 200 kt) as a Sloika (with an aluminum shell)?

55. SLOIKA WEAPONS - 4 The British Orange Herald Device

56. SLOIKA WEAPONS - 5 In the Russian & British cases, both abandoned the Sloika after successfully testing a radiation implosion weapon (lighter weight & higher yield)? But Sloika remains a viable and very "dirty" design & is well within the capability of any entity that can produce an implosion weapon Deliverable by rail, ship, submarine, or aircraft

57. SLOIKA WEAPONS - 6 Sloika (400 kt)? 2nd Generation Implosion Weapon ("Joe-2")? 1st Generation Implosion Weapon ("Joe-1")?

58. SLOIKA WEAPONS - 7 It is possible that Israel has developed a Sloika weapon This Mordechai Vanunu photo could be interpreted as a Sloika

59. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 1 From 1941-1945, the United States produced 4 nuclear devices of two different designs & developed plutonium production & separation as well as two different uranium enrichment processes in 3 years and spent about $20 billion in (2004 dollars based on CPI index escalation).

60. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 2 Subsequent modest nuclear weapons programmes (compared with the the US & Russia) are estimated to have cost �3.5-5 billion based on the experience from China, India, and South Africa. The cost of developing nuclear weapons has come down at least 4-fold since 1945.

61. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 3 In the middle 1960s, the predecessor of Lawrence Livermore National Laboratory (one of two nuclear weapon design labs in the US) conducted the so-called 'Nth' Country Experiment. Three individuals with B.S. degrees (2 in physics) were hired to design a nuclear weapon using only publicly available information. (One of the team quit, and was replaced by an Army Lieutenant with a PhD.)?

62. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 4 The team deliberately selected a spherical implosion device using plutonium because it was more challenging. Three person-years of effort was spent on the design (in 2.5 calendar years). The resulting device was too large for a missile, but could be carried by aircraft or truck. The design was evaluated using nuclear weapon codes at the time � it was concluded that a viable design had been produced.

63. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 5 Carey Sublette (curator of the Nuclear Weapons FAQ) has written, regarding the Nth Country Experiment, �In the years since, much more information has entered the public domain so that the level of effort required has obviously dropped further. This experiment established an upper limit on the required level of effort that is so low that the hope that lack of information may provide even a small degree of protection from proliferation is clearly a futile one.�

64. HOW HARD IS IT TO DESIGN A NUCLEAR WEAPON? - 6 The US Deparment of Energy has reportedly changed the security force criterion for facilities with weapons-grade material from preventing theft to preventing insertion of the material into a nuclear device and detonation in place

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