Scope and Verification of aFissile Material (Cutoff) Treaty
[Ref. Global Fissile Material Report 2008, http://fissilematerials.org/library/gfmr08.pdf]
Frank von Hippel Program on Science and Global Security, Princeton University and
International Panel on Fissile Materials
APS Short Course on Nuclear Weapon Issues in the 21st Century Elliot School of International Affairs, Washington, DC
3 Nov. 2013
Outline I. Scope. Just newly produced HEU and plutonium or materials declared excess for weapons or military use as well?
II. Detection of clandestine production
III. Verification challenges beyond those the IAEA has dealt with in non-weapon states. • Enrichment and reprocessing facilities not designed for safeguards • Enrichment facilities that have produced HEU in the past • Naval HEU fuel cycle • Managed access as military nuclear facilities
1996 G8 Moscow Nuclear Safety Summit. “We pledge…to ensure that all sensitive nuclear material (separated plutonium and highly enriched uranium) designated as not intended for use for meeting defence requirements is safely stored, protected and placed under I.A.E.A. safeguards …as soon as it is practicable to do so.”
2000 NPT Rev. Con. Final Document, practical step, #10 “to place, as soon as practicable, fissile material designated by each of [the NPT weapon states] as no longer required for military purposes under IAEA or other relevant international verification....”
2010 NPT Review Conference, Action 16. “The nuclear-weapon States are encouraged…to declare…to the…(IAEA) all fissile material designated by each of them as no longer required for military purposes and to place such material as soon as practicable under IAEA or other relevant, international verification….”
But we are now told that an FMCT that includes international monitoring of pre-existing non-weapons stocks is “not negotiable.”
I. Scope: P-5 repeatedly promised to put excess fissile materials under international safeguards
Weapon-state stocks of highly-enriched uranium (mid 2013) Much more could be declared excess for military purposes
5,000 warheads + 50-years
naval fuel (175) Met
ric to
ns H
EU
5,000 warheads + 50-years naval
fuel (225)
5,000 warheads (20)
Global stocks of separated plutonium Much more could be declared excess for military purposes
Status of IAEA verification of storage and disposition of excess Russian and US HEU and Pu
• IAEA monitored blend-down of ~50 tons of U.S. HEU and monitors storage of 2 tons of excess US Pu at Savannah River.
• US monitored blend-down of 500 tons (20,000 weapon equivalents) of excess Russian weapons HEU (1993-2013, Tom Neff initiative)
• Russia and the U.S. committed to IAEA verification of their disposition of 34 tons of weapon-grade plutonium each. Negotiations with IAEA in progress since 2010.
II. Detection of clandestine production(problem for both the NPT and FMCT)
1. Enrichment plant for HEU production 2. Reactor for plutonium production 3. Reprocessing plant for separation of plutonium from
irradiated uranium.
Identification of clandestine centrifuge enrichment plants not easy from a distance.
Iran’s Fordow enrichment plant was found by human intelligence.
Sensitive facility but what is it? • Not energy intensive. • Centrifuges and piping
under vacuum. Therefore not much leakage of UF6.
(Somewhat more leakage at UF6 production plant.
UF6 reacts with water vapor to produce UF2O2 +4HF.)
Tunnel entrances Spoil from tunnels
and rooms
Double security fence with lights & sensors
34o53’N, 51o0’E
Thermal imaging can detect Pu production reactor Hot water from C and K tritium/plutonium reactors flowing into swamp
next to Savannah River (aerial image, 1981)
"N SRlJRNNRH RIlJER PLRNTRUGUST 25.1981
+10 oC 2 km
Detection of reprocessing through gaseous fission product 85Kr(~20-400 kg [5-100 warheads]/yr detection threshold for 20% best-worst days)(R. Scott Kemp, “A performance estimate for the detection of undeclared nuclear-fuel reprocessing by
atmospheric 85Kr,” Journal of Environmental Radioactivity, 99, 2008, p. 1341.)
Also accumulation of other released radioisotopes in environment around reprocessing plant: C-14 (5600-yr half-life), H-3 (12-yrs), I-129 (17 million yrs), Ru-106 (~1 yr)
III. Verification ChallengesIAEA monitoring of enrichment & reprocessing and HEU and
separated Pu in unclassified forms could be adapted from safeguards in the non-weapon states. (IAEA needs more resources to implement.)
• All U.S. civilian nuclear facilities already offered for IAEA safeguards but IAEA does not safeguard because of limited resources and low priority.
• All civilian fissile materials and facilities in France and U.K. under Euratom safeguards.
• IAEA safeguards in China on enrichment plant provided by Russia.
Additional challenges in the weapon states
1. Reprocessing plants not designed for safeguards. 2. Enrichment plants that previously produced HEU. 3. Naval fuel cycles 4. Military nuclear facilities
Reprocessing plants not designed for safeguards
Only reprocessing plants under IAEA safeguards today are 2 in Japan; account for 20% of IAEA’s safeguards budget. Many measurements of stocks and flows within the plants.
Existing operating contaminated reprocessing plants with undocumented piping will have to be treated to a considerable extent as black boxes.
Balance inputs and outputs during annual shutdown and cleanout
Spent fuel (Need to improve estimates of plutonium in spent fuel.)
Radioactive waste
Plutonium oxide
Uranium oxide
Reprocessing plant
14
IAEA verifies nonproduction of HEU at enrichment plants by measuring enrichment of uranium particles on swipes with SIMS
(Secondary Ion Mass Spectrometry)
Scanning beam of cesium ions
What happens at target
Mass spectrometer for secondary ions
Image
www.psims.com/simstecn.htm
15
Sample SIMS images (0.15x0.15 mm, µ-sized particles)
U-235 concentration.
HEU particles U-238 concentration.
Natural uranium particles
Can HEU particles be dated?
Non-diversion of naval HEU
Under FMCT, monitoring of non-diversion eventually will be required of all countries that use new HEU as naval fuel unless they convert to LEU like France.
US, UK and Russia could postpone this day of reckoning by a century by using excess weapons HEU but India could not today.
Currently a loophole in safeguard agreement with non-weapon states, INFCIRC 153, Para. 14: “Non-application of Safeguards to Nuclear Material [in non-weapon states] to be Used in [non-explosive] Non-peaceful Activities”
Brazil first non-weapon state developing a propulsion reactor (fueled with LEU). IAEA is negotiating monitoring arrangements.
How to assure non-diversion of HEU produced for naval propulsion reactors (US, UK, Russia, India)?
HEU stockpile in unclassified form
Fuel-fabrication facility (US, ~2 tons/year, 80 bomb equiv.)
Fabricated fuel (nonintrusive assay?)
Installation of fuel in propulsion reactor.
Better would be to shift naval reactors to LEU fuel as France has done.
Operation of reactor.
Discharge of fuel (10-40 years later)
Stored spent fuel
Reprocessing (Russia +?)
Repository (U.S., UK +?)
Boxes outlined in red would be easiest. Others would require cooperation by nuclear navies.
Monitor fueling/defueling.
Then seals on fueling hatch and spent-fuel casks?
Challenge inspections (managed access) in military nuclear facilities to assure that they don’t do centrifuge enrichment
[e.g. US plutonium-pit facility (TA-55), secondary component production facility (Y-12) or naval fuel fabrication facility (BWXT)]
Issue would be to satisfy the IAEA that no undeclared enrichment activities were taking place while protecting design information re nuclear-weapons and naval-fuel.
Organization for Prevention of Chemical Weapons (OPCW) already has access to to assure the absence of nerve gas, etc.
Facilities allow entry of gas-chromatograph mass spectrometer with no memory & library only of signatures of chemical-weapon-related species, precursors and degradation products. Column material left on the site.
Could a laser-induced breakdown spectrometer be designed to detect UF6 breakdown products (UF2O2) on walls(e.g. positive signal if U & F detected in same spot)?
p
“Development of Laser Induced Breakdown Spectroscopy Instrumentation for Safeguards Applications”, J.E. Barefield II et al (LANL),
Symposium on International Safeguards, Vienna, 1-5 Nov. 2010.
NASA ChemCam on Curiosity
Conclusions
Verification challenges of an FMCT seem manageable – except perhaps for obtaining cooperation from nuclear navies for verifying non-diversion of HEU from the naval fuel cycle. (One more reason for moving to LEU fuel for naval reactors.)
