Mixing it up: A MOX fuel rod on Saturday is loadedinto a nuclear reactor in Fukushima Prefecture.KYODO PHOTO

Fukushima reactor receives MOX

FUKUSHIMA (Kyodo) Tokyo Electric Power Co. on Saturday loaded a nuclear reactor inFukushima Prefecture with MOX, a controversial fuel made with reprocessed plutonium anduranium oxides, as it prepares to become the leading power utility's first facility to gopluthermal.

The No. 3 reactor at Tepco's Fukushima No. 1 plant willbe the nation's third pluthermal facility, but only the first tobe refurbished since the plant was built 34 years ago.

Tokyo Electric plans to activate the reactor on Sept. 18and let it start generating electricity on Sept. 23.

The Japan Times: Monday, Aug. 23, 2010(C) All rights reserved

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OVER the next few weeks, two ships carrying a secret cargo of dangerous, nuclear weapons-usableplutonium fuel will leave ports in Britain and France and sail around the globe to Japan. On board willbe fuel containing more plutonium than in the entire Indian and Pakistani nuclear weaponsprogrammes.(1)

The two British flagged vessels, the Pacific Teal and the Pacific Pintail, will leave Barrow in Britainand Cherbourg in France carrying the first commercial shipment to Japan of mixed-oxide (MOX)reactor fuel, made from plutonium and uranium. An estimated 446 kilograms of plutonium iscontained in the 40 nuclear fuel elements – enough fissile material to construct 60 nuclear bombs.The International Atomic Energy Agency classifies this plutonium fuel as a “category one” “directuse” weapons material, and estimates it would take just 1-3 weeks to convert into nuclear bombs.

The shipments mark a new and dangerous phase of the nuclear industry; the plan to expand the use ofplutonium fuel (MOX) in conventional nuclear reactors in Japan and around the world. Thesereactors were not designed to burn plutonium fuel and its use will significantly reduce safety margins.Plants in the United Kingdom and France are set to massively expand production of MOX fuel ifJapan signs contracts based on a successful transport this year.

If the shipments are successful and MOX fabrication expands, then the international communityfaces 80 more such shipments over the next ten years, the spread of nuclear weapons material morewidely than ever before, and raised tensions in one of the most politically volatile regions of theworld – Asia. Public health and the environment will be put at increased risk from radioactivepollution and nuclear accidents, as reactors burn a fuel they were not designed to handle. Asplutonium is highly radio-toxic, the shipments will also pose a danger to countries en route. Whilethe probability of a transport accident may be low, the consequences for the environment and publichealth could be devastating.

ROUTE OF PLUTONIUM FUEL (MOX) SHIPMENT KEPT SECRET

THE plutonium (MOX) fuel shipment is being conducted for the Japanese electrical utilities TokyoElectric Power Company (TEPCO) and Kansai Electric Power Company (KEPCO) by Britain andFrance. The plutonium has been produced from the reprocessing of nuclear spent fuel at two sites inEurope: Sellafield in northern England, operated by British Nuclear Fuels Ltd (BNFL), and La Haguein North France, operated by COGEMA. These two sites are the largest producers of plutonium onthe planet. Combined, the sites have in storage more than 100 tonnes of plutonium -- more than isin the US nuclear weapons stockpile. The contracts for the production of the plutonium fuel weresigned on behalf of the Japanese utilities by Mitsubishi and Toshiba. Plutonium fuel for TEPCO hasbeen produced at Dessel in Belgium and transported by road to La Hague prior to sea shipment toJapan, where it will be loaded in the Fukushima nuclear power plant. The plutonium fuel for Kansaihas been produced at Sellafield and will be shipped directly to Japan for loading at the Takahamanuclear power plant. These pilot contracts are intended to test the technical and logistical feasibilityof a MOX fuel cycle extending from Japan to France, Britain and Belgium.

SECRET SHIPMENT

OF NUCLEAR BOMB

MATERIAL FROM

EUROPE TO JAPANJULY 1999

The route the shipment will take remains a closely guarded secret by Japanese, French and Britishauthorities and the operating companies. The nations along the various potential routes have notbeen informed nor asked for their permission for the shipment to travel through their regions. Giventhat more than fifty countries around the globe protested earlier Japanese plutonium and nuclearwaste shipments, the transporting countries have a strong interest in keeping the enroute nationsuninformed.

Based on previous transports of high level nuclear waste from Europe to Japan and a shipment ofplutonium in 1992, the imminent plutonium fuel shipments can be expected to take one of thefollowing three routes from Europe to Japan:

• south along the west coast of Africa, around the Cape of Good Hope, across the Indian Ocean andnorth through the Tasman Sea and South Pacific (the route of the 1992 Akatsuki Maruplutonium shipment)

• west across the Atlantic Ocean, through the Mona Passage, across the Caribbean Sea, through thePanama Canal and across the Pacific (this was the route of high level nuclear waste shipments of1998 and 1999)

• southwest across the Atlantic, along the east coast of Latin America, around Cape Horn andnorthwest across the Pacific (this was the route of the first high level nuclear waste in 1995)

Assuming that the two and a half month voyage is made without mishap, the two freighters will enterJapanese waters and unload their plutonium cargoes in the private harbours which service theFukushima and Takahama reactors.

INADEQUATE SECURITY ARRANGEMENTS FOR THE VESSELS

THE two freighters carrying the plutonium fuel, the “Pacific Pintail” and the “Pacific Teal”, are bothoperated by Pacific Nuclear Transport Limited (PNTL), which is owned by BNFL, COGEMA and theJapan Federation of Electrical Power Companies. Because international regulations require militarysecurity arrangements for cargoes of nuclear bomb-usable material, the ships will be armed with 30mm cannons and carry armed UK Atomic Energy Agency police, which normally guard Britishnuclear weapons facilities.

A previous shipment of plutonium from Europe to Japan in 1992 was accompanied by a Japanesenaval escort that included a warship loaded with commando boats, machine guns and helicopters.However, because the nuclear industry wants to cut costs and portray the upcoming shipment as aroutine commercial transport rather than a proliferation threat, the two civilian vessels will act as anescort for each other. This arrangement is clearly inadequate to deter any determined physical attackand in fact creates more hazards by storing ammunition and explosives together with large quantitiesof fuel oil and plutonium on the same vessel.

A 1988 US Department of Defense threat assessment report on plutonium shipments concluded thatin order to "adequately deter theft or sabotage, it would be necessary to provide a dedicated surfacecombatant to escort the vessel throughout the trip". Even with an escort "no one could guarantee thesafety of the cargo from a security incident, such as an attack on the vessel by small, fast craft,especially if armed with modern anti-ship missiles.”

The United States has a legal responsibility for the security of the plutonium fuel shipments to Japanas it originated from US enriched uranium and is therefore covered by US rules of origin. This meansthat plans for the transport of MOX fuel from Europe to Japan must comply with specific USrequirements concerning safety and physical protection. These are set out in the 1988 US-Japanagreement on nuclear co-operation and include the requirement either that the transport ship should

be accompanied by an armed escort vessel or that alternative security measures acceptable to the USshould be in place.

In February this year the Chairman of the US House of Representatives International RelationsCommittee, Benjamin Gilman, expressed his concern that the transportation plan does not meet, oris not equivalent, to the physical protection measures specified in the 1988 Japan-U.S. agreement. Ina letter to Secretary of State Madeleine Albright (11th Feb 1999), Gilman said:

“In my view, escort vessels which are minimally armed and have a top speed of 13 knots, would notappear to have sufficient defensive and deterrent ability, much less the manoeuvrability or speed ofmilitary or coast guard escort ships. With regard to armaments, I would expect that any proposedescort vessel would include a radar-directed, anti-missile defence system.“At a minimum, the measures applied to the 1992 shipment of separated plutonium should be usedfor this MOX shipment, including the use of an armed escort vessel for the entire voyage.”

Despite these concerns the U.S. State Department has approved the present security arrangements,raising questions about the Clinton Administration's commitment to applying an effective andconsistent nuclear non-proliferation policy.

PLUTONIUM – THE BASIC INGREDIENT OF A NUCLEAR BOMB

PLUTONIUM is a highly radio-toxic element, all but non-existent in nature, which is produced innuclear reactors. Inhalation of a single microgram, smaller than a speck of dust, can cause fatal lungcancer. Plutonium is the most highly prized fuel—or fissionable material—for making nuclearweapons, and has been an essential fuel driving the nuclear arms race over the last half century. Givenits long half-life, some 24,000 years, once produced, plutonium remains a deadly environmentalcontaminant and a potential fuel for nuclear weapons.

Plutonium is produced as a nuclear reactors uranium fuel becomes irradiated -- bombarded by neutrons-- some of the uranium is changed into plutonium and remains contained in the irradiated or ‘spent’nuclear fuel. In the case of “military production reactors” this process of plutonium production ismaximised, but all conventional nuclear power reactors produce plutonium.

In order to access this plutonium for nuclear weapons purposes, the nuclear weapons states developeda very dirty and dangerous chemical separation technology known as “reprocessing”. Through thisprocess, the spent fuel is chopped up, chemically dissolved and the plutonium is separated out of theresulting stew of highly radioactive, long-lived nuclear waste. This process involves massive routinedischarges of radioactivity to the air and sea, tremendous risks of explosions, radioactive releases, andworker exposure. The two major reprocessing plants in the world are located at Sellafield in theUnited Kingdom and La Hague in France.

The nuclear industry’s original plan was to use plutonium in “fast breeder reactors” which wouldbreed, or generate, more plutonium than they used. With the technical and economic collapse ofthese breeder reactors world-wide, the plutonium reprocessing industry faced a dead end. So theindustry is now proposing burning plutonium mixed with uranium (MOX) in conventional, light waterreactors.

The nuclear industry claims that extracting plutonium from the MOX fuel is a technicallycomplicated process that thus reduces the risk of its diversion into nuclear weapons programmes, orthe risk of seizure by terrorists. However in reality MOX fuel can be handled with little difficulty andplutonium can be extracted in any reasonably well-equipped laboratory using standard chemicalprocesses. Dr Frank Barnaby, a nuclear physicist who worked at the UK's Nuclear WeaponsEstablishment at Aldermaston between 1951 and 57, says: "If a terrorist group acquired MOX fuel, itcould relatively easily chemically separate the plutonium and fabricate a nuclear explosive". The U.S.Department of Energy’s Office of Arms Control and Non-Proliferation also acknowledged this point

in a 1997 report: "Nevertheless, it is important to understand that fresh MOX fuel remains a materialin the most sensitive category because plutonium suitable for use in weapons could be separated fromit relatively easily".

A NUCLEAR ACCIDENT THAT CAN’T HAPPEN?

ALTHOUGH an accident involving the release of even a small fraction of the plutonium contained inone of these shipments could have devastating results for the environment and public health, safetyconsiderations have been seriously jeopardised by cost-cutting and secrecy. Inadequate design, testingand construction of the transport containers, insufficient emergency planning, and inadequateliability coverage suggest that the industry and governments involved are simply unwilling to pay thecost of making anything but their profits safe.

The plutonium fuel is to be carried in type-B nuclear transport flasks that were designed to carryspent fuel. Under IAEA regulations such flasks are designed to withstand a drop of nine meters on toan unyielding surface (13 metres/second), being engulfed in fire at 800 degrees C for 30 minutes, andimmersion at a depth of 15 metres for eight hours. Transports can be by road, rail, sea or air.

Regardless of the transport mode, the design specifications of the flask can be easily exceeded. For example, a fire raged aboardthe ferry Moby Prince for over 45 hours and exceeded 1,000 degrees C after it collided with an oil petroleum tanker, the AgipAbrozzo, off the Italian port of Livorno in 1991. According to the International Maritime Organisation (IMO), on average,shipboard fires burn for 23 hours at sea and 20 hours in port, while the US Department of Energy admits that petroleum fires canexceed 1,000 degrees C.

Under existing liability agreements, there is no certainty that compensation would be paid to enroutestates in the event of an accident. At best, international conventions and other arrangements mayprovide some compensation, but no assurances exist whatsoever that the full costs of health,environmental and economic damages would be paid to victims enroute states.

CONCLUSION

UNLESS international controversy puts a stop to future shipments of plutonium fuelaround the world, a new and deadly phase in the nuclear cycle will be established. Theproposal to burn plutonium (MOX) fuel in conventional reactors -- a proposal intended tojustify the survival of the plutonium programmes of Britain, France and Japan --threatens to create dangerous nuclear proliferation and environmental risks. Theshipments therefore undermine international non-proliferation objectives and put thehealth and security of millions of people in danger. The only way forward is to stop thereprocessing of plutonium and cancel plans for the use of MOX fuel in nuclear reactorsglobally. Unless this occurs, growing stockpiles of “civil” plutonium will soon rivalmilitary stockpiles, and international attempts to agree an effective and verifiable ban onthe production and use of plutonium and other fissile materials will be fatallyundermined.

(1) The current plutonium stockpile of India is estimated to be 350kg and the plutonium-equivalent of Pakistan’sstockpile, 67.2kg, giving a total of 417kg, according to a 1999 report by David Albright of the Institute for Science andInternational Security, based in Washington D.C. Albright was a member of the United Nations weapons inspection teamin Iraq.

For more information contact: Greenpeace International Nuclear Campaign +31 20 5236222 or the Greenpeace International Press desk +31 20 524 9547/46Greenpeace on the web: www.greenpeace.org

Nuclear Fuel Cycles: Differences and Similarties

Mujid S. Kazimi TEPCO Professor of Nuclear Engineering

Director, Center for Advanced Nuclear Energy Systems, MIT

October 12, 2010 Panel on Advantages and Disadvantages of New Fuel Cycles

Subcommittee on Reactor and Fuel Cycle Technology Blue Ribbon Commission

Attributes of a Desirable Fuel Cycle •  Economic. Here the emphasis is on what is the cost of the associated

technology, since that cost is currently about 70% of the cost of nuclear electricity.

•  Has Vast Fuel Resource. Maximizing the utilization of the energy potential from nuclear fuel is a benefit for mankind as it provides many future generations of an option for their needed energy.

•  Minimizes the burden of waste products. Thus the handling of waste products in the short and long term would pose negligible risk to the public and the environment.

•  Maximizes the proliferation resistance associated with its operations. Thus, the fuel should be undesirable as a potential weapons material at any of the stages involved. The treatment of the fuel to make it a desirable weapons material should be complex and costly.

Why economics can improve •  The most economic nuclear fuel cycle is the once-through use of mined

uranium in LWRs, as long as uranium supplies remain inexpensive. –  The predominant choice of all countries demonstrates this attribute. –  Shares technology development costs with fossil power plants (pumps, valves,

turbines, etc) –  Has a relatively wide industrial base, so it does not require starting from scratch –  Benefit from lessons learned from construction and operation of over 300 plants all

over the world.

•  Steps that might further reduce the cost of the plants per KWe: –  Standardization: Exemplified by France and Korea, may provide 20% reduction –  Power Uprates: New designs of fuel, new operating conditions and new coolant

technology (nanofluids) should help reduce the cost by 20% –  New construction techniques may reduce by 10% –  New licensing process, may reduce by 10% –  Elimination of the financing risk premium (support for first movers, and development of

medium size reactors (500 to 1000MWe).

Fuel Cycle Basics

•  If nuclear deployment does not increase substantially, once-through will remain the preferred option. However, if nuclear growth is large, then at some future date, fuel breeding in reactors will become attractive, justifying fuel partitioning and recycling of useful parts.

•  For the same nuclear energy output, all fuel cycles produce roughly the same fission products, thus, roughly equal burden for heat removal from used fuel in storage for the first 200 years. Advanced fuel cycles with recycling can dramatically reduce the transuranic loading (i.e. long term heat load) of a repository, not the fission product burden.

•  The transition from the once-through cycle to a closed cycle has a slow dynamic, and a complex interdependence of many factors. Thus, a study of fuel cycle dynamics is needed to understand the influence of these multi-coupled factors in growth scenarios of nuclear power.

Choices: Reactors and Recycling 1 GWe Light Water Reactor (LWR) •  A core contains 90 MT of heavy metal, requires 20 MT/yr of 4.5% enriched U •  Spent fuel (SNF) contains about 1% TRU, of which 90% is Pu and 10% MA, •  Thus about 0.2 MT of TRU in spent fuel is discharged per year •  11 years of operation of 1 LWR is needed to provide one batch of fresh MOX •  Large commercial reprocessing plant 800MT/yr: nearly 0.9 years of

operation per one initial MOX core •  Multirecycling in thermal spectrum LWRs is more challenging than in fast

reactors due to buildup of spontaneous neutron sources and non-fissile Pu and MAs

1 GWe Fast Reactor with Recycle •  Initial core requires 7 to 10 MT TRU plus about 50 MT U •  35 -50 years of operation of 1 LWR to start 1 FR •  Large commercial reprocessing plant 800MT/yr: nearly 1 year of operation

per one initial FR core •  Alternative startup on enriched uranium (at <15% enrichment) is possible for

reactors that have a conversion ratio of 1.0 •  A full FR core with unity conversion ratio produces yields fuel for one FR

fresh core. More for breeders (since CR>1).

Modeled Multiple Fuel Cycles Over a Century

Three nuclear growth rates: 1, 2.5, and 4% per year Three fuel cycle options: Light-water reactor once-through fuel cycle Light-water reactor with recycle of LWR SNF Light-water reactor SNF TRU to fast reactors

Fast reactors with three conversion rates (rate of fissile fuel production versus consumption) CR = 0.75 (Actinide burner) CR = 1.0 (Make fuel as fast as consume fuel) CR = 1.23* (Make fuel faster than consume fuel)

*Traditional future vision of closed fuel cycle using 1970s assumptions

Installed LWR Capacity on UO2 Fuel (2.5% Growth Case)

7

FR Startup Limited by Availability of TRU from LWRs

Fuel Cycle By 2050 By 2100

Once-Through LWR 1.26 5.86

MOX LWR 1.11 4.86 LWR-Fast Reactor:

CR = 0.75 1.21 4.16

LWR-Fast Reactor CR = 1.0

1.21 3.78

LWR-Fast Reactor CR = 1.23

1.21 3.76

8

Cumulative Demand for Uranium (1M MT)�MOX has little effect, and fast reactors take decades �

to cause a real difference

2.5 % Growth Rate

Cumulative Demand for Uranium (1000 MT) MOX has little effect, and fast reactors take decades

to cause a real difference Growth Rate Fuel Cycle By 2050 By 2100

OTC 1,105 3,064

1.0% MOX 961 2,516

FR* 1,058 1,970

2.5% OTC 1,382 6,299 MOX 1,226 5,361 FR* 1,311 4,060

4.0% OTC 1,749 8,591 MOX 1,593 7,295 FR* 1,679 5,831

* For Conversion ratio =1.0

Total TRU in system for 2.5% case Recycling has a modest effect on total TRU in the system.

Total TRU = TRU In Reactors + Cooling and Interim Storage + Repository

10

Location of TRU in LWR-FR System Most TRU is in cooling storage and in fast reactor cores

2.5% Growth LWR with TRU to FR

FR Conversion Ratio = 1

11

TRU in wastes for 2.5% case Significant reduction of TRU to repository is possible via recycling

Conclusions for Growth Scenarios

•  Transition times between fuel cycles are 50 to 100 years •  LWRs will have a major role in nuclear energy in this century •  Recycling has limited impact on natural uranium consumption

in this century •  Recycling does not lead to appreciable reduction of TRU in

total energy system in this century, but leads to significant reduction in the amount of TRU destined to the repository in the short term

•  There is little difference in outcomes with a fast reactor with a conversion ratio of 1 versus 1.23

13

Implications from Dynamic Systems Analysis and Advancing Technologies

•  Lowering CR to 1 (from the historical CR>1.2) opens up multiple sustainable reactor options –  Sodium fast reactor (Historical base case)

• Chosen in the 1970s based on uranium resource understandings, limited capability to model CR implications, and available technologies

–  Hard-spectrum LWR –  Gas-cooled fast reactor –  Salt-cooled high-temperature reactor

•  Some of these new options may have superior economics and other characteristics

•  The fuel cycle with CR=1 reactors will minimize the needed recycling technology capacity.

•  CR ~1 may enable startup of fast reactors on low-enriched uranium 14

Implications For Future Technologies

Pacific Northwest International Conference on Global Nuclear Security, April 11-16, 2010,

Portland, OR

1

Commercial Viability of Mixed Oxide Fuel Transport

in the United States

Frederick Yapuncich*, Dorothy Davidson*, Remi Bera*, Michael Valenzano**

*AREVA Federal Services LLC, Bethesda, MD 20814

**Transnuclear, Inc., Columbia, MD 21045

ABSTRACT

The commercial viability of a Mixed Oxide (MOX) fuel feedstock for United States (US) nuclear

power stations is predicated on the US regulatory framework and the physical infrastructure of

these plants. MOX fuel is a blend of uranium oxide and plutonium oxide. The commercial

reactors in the United States currently rely on traditional fresh uranium feedstock. However, the

international community has been utilizing reactor grade MOX fuel since 1972. A basic review

of these fuel types in conjunction with the safety and security issues associated with the transport

of this material is presented. An overview of various MOX fuel shipping casks is also provided.

Recommendations to optimize the use of MOX fuel in the US are developed based on a

comparison of the US transport regulatory culture and the international model. These security

recommendations include privatization of certain aspects of the transport of MOX fuel and the

harmonization of NRC/DOE classifications. Development of MOX transport systems amenable

to the applicable MOX fuel fabrication plant and the respective utilities’ fresh fuel assembly

receipt infrastructure is necessary.

INTRODUCTION

The nuclear industry is currently implementing or preparing to implement MOX fuel re-loads in

a number of countries (France, Germany, Switzerland, Belgium, Great Britain, Japan and

Holland). As of today, 35 reactors are currently loading MOX in Europe. Comprehensive

transport systems fully compliant with current Safeguards and Physical Protection requirements

in these countries have been developed. The industry is operating MOX transportation on a

routine basis and has succeeded in streamlining transportation costs while maintaining the

required high level of safety and security.

In the US, the industry proposes to conduct MOX fuel commercial operations in conjunction

with existing fresh fuel operations. The mission is to conduct commercial MOX transport

operations with high capacity MOX transport casks and high security vehicles fully compliant

with the US regulatory framework.

Nuclear Reactor Fuel Streams

Currently there are two fuel streams for light water reactors: fresh uranium dioxide fuel and

MOX fuel. Fresh uranium is mined, enriched, and manufactured into fuel assemblies. The

enrichment level is typically 3-5%. Based on the current regulations governing fresh uranium

fuel, the shipment of this fuel stream is allowed by commercial carrier in the United States and

internationally.

Reprocessed uranium is derived from the treatment process which chemically separates the used

nuclear fuel’s various constituents into uranium, plutonium, and nuclear waste [1]. The

reprocessed uranium is eventually converted into a solid form, re-enriched and recycled [2].

2

This reprocessed enriched uranium is shipped similar to fresh enriched uranium. The plutonium,

from the treatment cycle, is converted into oxide powder and is shipped in sealed canisters that

are subject to the applicable transport regulations of the specific country involved [1].

Mixed oxide, or MOX fuel, is a blend of uranium and plutonium which behaves similarly to the

enriched fresh uranium fuel. The plutonium in MOX fuel can be derived from either spent fuel

discharged from reactors or nuclear weapons material.

Reactor grade MOX, derived from commercial reactor spent fuel, contains quantities of fissile

(U-235, Pu-239, and Pu-241) and fertile (U-238) material. Uranium and recovered plutonium

constitute the basis for reactor grade MOX fuel.

Weapons grade MOX is derived from surplus nuclear weapons. The main difference between

weapons grade plutonium and reactor grade plutonium is the percentage of the plutonium

isotopes present in each fuel type. Table I [3] delineates the difference between these two fuel

streams.

Table I. Plutonium Isotopic Compositions of Weapons Grade and Reactor Grade MOX [3]

Transport of Reactor Fuel Streams

The transport of reactor fuel is governed by the domestic regulations of each country.

International institutions, such as the IAEA, issue recommendations and standards but are not a

regulatory body. Both safety and security issues must be addressed to properly transport any

type of nuclear fuel.

The ―packaging‖ of a radiological transport system typically consists of the cask assembly

including impact limiter, cask body, etc. The conveyance consists of a vehicle (e.g. trailer and

truck) utilized to transport the packaging.

Safety Aspect of Transport

The obvious purpose of safety regulations is the well being of the public, workers, and

environment. The major concerns of any radiological shipment are: containment, shielding, and

criticality. To optimize the transport of MOX fuel, it is necessary to evaluate each MOX fuel

3

type against these concerns. The isotopic differences between reactor grade and weapons grade

MOX drives the design aspects for shipment of these fuel types.

Description of Safety

One of the main discriminators in ascertaining the complexity of a normal form radiological

shipment is the ―A2‖ value associated with the radio-nuclides in the payload. The ―A2‖ factor,

generally speaking, aids in determining the allowed external and internal exposure of normal

radioactive transport material for a first responder. In gross terms, the lower the A2 limit, the

more stringent the design requirements.

If a particular payload has an activity which is less than the published A2 limit, the cask to

transport this material may be designed to meet Type ―A‖ requirements. A Type ―B‖ cask must

be used for transporting payloads for which the activity exceeds the A2 limits. Type ―B‖ casks

have much more stringent design requirements than Type ―A‖ casks. A Type AF cask transports

a payload with an activity of A2 or less, but which is fissile.

In fresh uranium fuel, the isotope of interest is U-235 and the A2 value for this radionuclide is

unlimited [4] which allows fresh fuel to be shipped in a Type AF container. Conversely, Pu-239

has an ―A2‖ value of 1.0X10-3

terabecquerel [4]. This low A2 limit forces MOX fuel assemblies

to be transported in a Type B container.

Furthermore, as shown in Table I, reactor grade MOX has higher concentrations of Pu-238, Pu-

240, Pu-241, and Pu-242. In addition, Pu-241 decays to Am-241. The concentrations of these

radioactive isotopes necessitate additional shielding measures for reactor grade MOX fuel.

MOX TRANSPORTS

Introduction

Internationally, reactor grade MOX has been transported since the early 1970s. Casks such as

the FS69, MX6, and MX8 have been extensively utilized for this work. The design of a transport

for fresh or reactor grade MOX fuel is essentially the same in the United States or

internationally. However, production scale shipment of weapons grade MOX has not been

commercially undertaken.

MX6 and MX8 [5]

The Transnuclear International FS 69 cask was used in France beginning in 1987 to deliver

MOX fuel to Électricité de France (EDF) power plants. MX8 cask development was launched in

1997 for the French market. MX6 cask development was launched in early 2000 for the

European market. The MX6 and MX8 casks have been developed by TN International to

transport fresh MOX fuel assemblies for both BWRs and PWRs. These casks replace the

previous Siemens type III, Siemens BWR, and FS 69 casks.

The TNI MX6 and MX8 casks are designed to transport both reactor grade and weapons grade

MOX fuel. This design approach could be useful for the US industry. The MX6 design enables

transportation up to six (6) PWR fresh MOX fuel assemblies and up to sixteen (16) BWR fresh

MOX fuel assemblies (Figure 1). It has a total gross weight of less than 20 metric tons (MT)

4

with a total length of 5,980 mm, a body diameter of 1,340 mm and a shock absorber diameter of

2,130 mm.

Fig. 1. MX6 cask with BWR basket.

The MX8 cask (Figure 2) can be loaded with 8 PWR MOX fuel assemblies. It has a total gross

weight of around 22 MT, a total length of 5,183 mm, a body diameter of 1,379 mm and a shock

absorber diameter of 2,282 mm.

Fig. 2. MX8 cask with PWR basket.

5

The MX8 cask design was approved by the French authorities in France in November 2001, and

fully extended since December 2006. The MX6 cask design was approved by the French

authorities in France in December 2002 and in Germany by the German authorities since October

2003. It has also been validated in Switzerland.

SECURITY ASPECTS OF FRESH NUCLEAR FUEL

United States Approach

―Special Nuclear Material‖ (SNM) is defined in the Atomic Energy Act of 1954 as plutonium,

uranium-233, or uranium enriched in the isotopes uranium-233 or uranium-235. MOX Fuel,

given the presence of plutonium and uranium, is considered SNM. SNM categories have been

developed by NRC and DOE to determine the appropriate safeguard measures for a given SNM.

DOE utilizes a graded approach that evaluates the ―attractiveness level‖ of the material. This

process determines the appropriate safeguard category by evaluating the ease of detecting theft

or diversion and the additional processing steps that would be necessary to convert the SNM into

a form for illicit use. NRC, as with the IAEA, considers only mass amounts to classify material.

With respect to MOX fuel, Table II provides the current definition for safeguards categories for

plutonium, as established by DOE and by NRC.

Table II. Current Safeguards Categories for Low-grade Plutonium [6]

DOE NRC and IAEA

Category Quantity (kg) Category Quantity (kg)

ID N/A I >2.0

IID >16 II 0.5-2.0

IIID ≥3, <16 III 15 g-0.5

IVD <3

In the United States, the Nuclear Regulatory Commission has codified the SNM transit

requirements. The transport requirements for Category I SNM are delineated in 10CFR 73.25.

This section defines the performance capabilities for physical protection of strategic SNM in

transit. 10CFR 73.67 delineates in-transit requirements for the physical protection of special

nuclear material of moderate and low strategic significance which are equivalent to Category II

and Category III SNM, respectively.

Given that typical reactor grade PWR MOX fuel assembly contains approximately 10% of

plutonium per weight of heavy metal, shipments are considered Category I by the NRC based on

mass of the SNM only. Due to the challenges of illicit removal of large heavy fuel assemblies

from ―in route‖ transport casks in conjunction with the complexities of extracting plutonium

from manufactured MOX fuel assemblies, it is assumed this material would be reclassified if a

DOE type graded approach was utilized. Through “Rulemaking Plan: Part 74 – Material Control

and Accounting of Special Nuclear Material,‖ NRC has recommended that a Commission paper

that describes DOE’s risk based categorization program be authored [7]. The outcome of this

6

NRC paper could positively affect the commercial viability of MOX shipments in the United

States.

Currently, only the National Nuclear Security Administration (NNSA) Office of Secure

Transportation (OST) has developed transport systems that meet the NRC requirements for

transporting Category I quantities of SNM. Assuming the introduction of MOX fuel as

feedstock to US reactors, private entities may be interested in developing this transport

capability.

It is worthwhile to point out that some of the shipments shown in Table III [3] of MOX fuel were

transported in the United States by private shippers prior to the DOE taking charge of this type of

transport. The precedent has been set for private shippers to conduct US MOX transports

adhering to NRC/DOE regulations.

Table III. United States MOX Transports [3]

International Approach

As shown in Table II, the category classifications for SNM (including Pu) utilized by the

international community and NRC are identical. The key difference is in the implementation of

this security. The steps in Table IV delineate the international security approach based on the

IAEA standard ―The Physical Protection of Nuclear Material and Nuclear Facilities”

(INFCIRC/225/Rev.4) [8].

7

Table IV. Overview of INFCIRC/225/Rev.4 [8]

1. IAEA recommends to Member States…. To provide a set of recommendations on

requirements for the physical protection of nuclear material… during transport... The

recommendations are provided for consideration by the competent authorities in the States. Such

recommendations provide guidance but are not mandatory upon a State and do not infringe the

sovereign rights of States….

2. Member States develop regulations/laws governing safety/security… To establish

conditions which would minimize the possibilities for unauthorized removal of nuclear material

and/or for sabotage…..

3. Industry adheres to domestic regulations through the development of transport plans,

design of cask and trailers/trucks, and qualifications of transport drivers...

4. Member States conduct inspections of industry to ensure both safety and security are

being met….. the State's competent authority should ensure that evaluations are conducted

…..for transport. Such evaluations, which should be reviewed by the State's competent authority,

should include administrative and technical measures, such as testing of detection, assessment

and communications systems and reviews of the implementation of physical protection

procedures….

In France, under this approach, the Competent Authority defines the specification of secured

conveyance, approves the design, and operates its communication center for real-time tracking of

the shipment. The fleet of vehicles, drivers, design and manufacturing is the responsibility of the

private sector with government oversight.

More extensive transports to Japan involving multiple countries and ocean transits have been

successfully performed. In France, over 150 MTHM/yr of French MOX capacity is dedicated to

twenty 900 PWRs with 30% of each core comprised of MOX fuel assemblies.

CONCLUSION

The harmonization of NRC/DOE safeguard categories in conjunction with the reclassification of

MOX fuel assemblies based on ―attractiveness levels‖ would be a positive first step in

optimizing United States MOX shipments.

However, to successfully introduce this fuel into the United States nuclear fuel cycle, it will be

necessary to align the transport process with the international community. This approach will

8

place the open and closed fuel cycle on a similar risk basis. The concept of privately owned and

operated conveyances under governmental escorts has been shown to meet the commercial

demands for MOX fuel while establishing an unblemished safety and security record for over

thirty years. This approach has the additional benefit of ―freeing up‖ US governmental resources

to concentrate on higher transport priorities.

The efficiency of the international MOX transportation model is based on the assumption that the

cask and conveyance designs can be developed by one engineering entity. For example, the

incorporation of physical security measures into the cask design has found to aid in the

optimization of the MOX fuel shipping campaigns while adhering to the appropriate safety

regulations. Development of MOX transport systems amenable to the applicable MOX fuel

fabrication plant and the utilities’ fresh fuel assembly receipt infrastructure is also necessary.

To ensure a successful outcome, the design of the US commercial MOX transport system should

involve both domestic and international stakeholders.

REFERENCES

1. ―MOX Fuel Transport from Europe to Japan‖ AREVA, INS, ORC, (2009).

2. ―Management of Reprocessed Uranium, Current Status and Future Prospects‖, IAEA-

TECDOC-1529 (2007).

3. ―Program on Technology Innovation: Readiness of Existing and New U.S. Reactors for

MOX Fuel, (Table 1-1 Kang et al, DCS, IAEA, Trellue)‖, EPRI, Palo Alto, CA: 1018896,

(2009).

4. ―Part 71—Packaging and Transportation of Radioactive Material‖, United States Nuclear

Regulatory Commission‖, www.nrc.gov/reading-rm/doc-collections/cfr/part071/

5. C. Otton, T. Lallemant,―Transport of MOX Fuel: A Continuous Challenge‖, TN International

(AREVA group), (2009).

6. S.B. Ludwig, et al. ―Programmatic and Technical Requirements for the FMDP Fresh MOX

Fuel Transport Package‖, ORNL/TM-13526, (1997).

7. ―Rulemaking Plan: Part 74 – Material Control and Accounting of Special Nuclear Material‖,

SECY-08-0059, U.S. NRC.

8. ―The Physical Protection of Nuclear Material and Nuclear Facilities‖, INFCIR/225/Rev.4,

www.iaea.org/Publications/Documents/Infcircs/1999/infcirc225r4c/rev4_content.html.

IEER ENERGY &SECURITY No. 3

The Use of Weapons Plutonium as Reactor FuelBy Arjun Makhijani and Anita Seth

At the end of the Cold War, the United States and Russia face an unprecedented and unexpectedproblem: surpluses of plutonium and highly-enriched uranium (HEU), the two key materials used to makenuclear weapons. In principle, the uranium poses the lesser problem of the two, because it can beblended down into the low-enriched uranium fuel that is widely used in nuclear reactors. In 1993, theUnited States and Russia signed a deal according to which the United States agreed to purchase, over aperiod of 20 years, 500 metric tons of Russian HEU that is being blended down into reactor fuel inRussia. Although implementation of this agreement was initially slow, it is now going forward at theagreed rate.

More difficult is the issue of converting the surplus plutonium into forms not usable for making nuclearweapons. The United States has declared about 50 metric tons (out of a total stock of about 100 metrictons) to be surplus,1 while Russia has not yet made any formal declaration of surplus. Total Russianplutonium in the military sector is thought to be about 130 metric tons, perhaps more.

There is disagreement between the United States and Russia about the best way to handle surplusweapons plutonium. The Russian Ministry of Atomic Energy (Minatom) regards plutonium as a valuableenergy resource, but the prevailing US view (notwithstanding some disagreements that continue) is that itis a security and economic liability. Despite their conceptual differences, the United States and Russiahave been working together since 1994 on methods for disposition of this surplus weapons plutonium.The Joint United States/Russian Plutonium Disposition Study, prepared by teams of scientists andofficials from both countries and published in September 1996, is one result of this joint work.

The joint study outlines a number of options, and reflects agreements as well as disagreements betweenthe governments of the two countries. Both governments agree that it is very important to put surplusmilitary plutonium into non-weapons-usable forms in a timely manner. In the report, the US and Russiapresent four options jointly, while Russia presented two options in addition on its own. The four jointlypresented options are:

1. use as MOX in light water or heavy water reactors

2. use as MOX in fast reactors

3. immobilization in glass or ceramics

4. direct geologic disposal of plutonium

The two options presented by the Russian side alone are: (i) high-temperature gas reactors, and(ii) accelerator-based systems.

The first two reactor options involve using plutonium in reactor fuel. The plutonium would beconverted into an oxide chemical form, mixed with uranium oxide, and fabricated into ceramic fuelpellets (called MOX fuel for short). The isotope of uranium used in MOX fuel is uranium-238, whichis not fissile. MOX fuel would be put into fuel rods and loaded into reactors as a complete or partialsubstitute for the uranium fuel currently used, which is enriched in the fissile isotope, uranium-235.Of the options considered, MOX fuel (in LWRs and fast reactors) and immobilization (the mixing ofplutonium with glass or ceramics), are the two technologies under serious consideration forimplementation in the near-term.

The study concludes that the most mature of the technologies considered are those involving"reactor options involving known and demonstrated reactors and MOX fabrication technologies."Immobilization technologies are deemed the next most mature. This judgment is based primarily onthe European experience of using MOX in LWRs, and Russian experience in the development ofMOX fuel for fast reactors. However, a number of differences between civilian plutonium (used inEurope) and military plutonium make this judgment less certain. Further, the decades of Europeanexperience in vitrification (the most developed method of immobilization) of high level radioactivewaste appears not to have been factored into the overall judgment of relative technological maturity.

Recognizing the differences that exist between the two governments, the report states that "theUnited States and Russia need not use the same plutonium disposition technology. Indeed, giventhe very different economic circumstances, nuclear infrastructures, and fuel cycle policies in the twocountries, it is likely that the best approaches will be different in the two countries."2 Furthermore,each country may use more than one option.

MOX fabrication3

MOX has not been fabricated from weapons-grade plutonium on an industrial scale. Currentindustrial MOX facilities use plutonium dioxide derived from facilities that reprocess spent powerreactor fuel (called reactor-grade plutonium). There are some important differences. Commercialreprocessing plants currently use aqueous technology (that is, acids and other liquid solvents) toseparate plutonium and uranium in spent fuel from fission products and from each other. The finalproduct is a plutonium dioxide powder that can be directly used in MOX fuel production. In contrast,most military plutonium is in the form of "pits" which consist of plutonium metal with small quantitiesof other materials. Further, in the United States and Russia (and probably in other nuclear weaponsstates as well) weapons plutonium is alloyed with up to one percent gallium. Gallium complicatesthe MOX fuel fabrication process and therefore it must be almost completely removed fromweapons grade plutonium prior to fuel fabrication. Hence, weapons plutonium metal must both bepurified and converted into oxide form (not necessarily in that order) before it can be used. Thus,MOX fuel fabrication from weapons-grade plutonium involves steps and processes that are notneeded for reprocessed plutonium from power reactor fuel.4

The current processes for making weapons plutonium into suitable feed for a MOX fuel fabricationplant use aqueous technology similar to reprocessing, which involves huge liquid waste discharges(for more information on reprocessing, see E&S #2 and Science for Democratic Action Vol. 5No. 1). Dry processes that could be used to make plutonium oxide and remove gallium have not yetbeen developed beyond the laboratory scale. They will take four to five years more to reach theindustrial scale needed for plutonium disposition using MOX. The U.S. has declared its intent touse the dry ARIES process to remove gallium from plutonium pits, while Russia is primarilyconsidering aqueous and molten salt technologies (it is cooperating in this work with France).

In the United States, MOX fuel was used in tests in LWRs during the 1960s and 1970s. MOX hasbeen made in the U.S. only in small-scale glove-box facilities. If the U.S. decides to pursue a MOXoption, it would have to construct a new fuel fabrication plant or complete the partially-finished FuelMaterials Examination Facility at the Hanford site in Washington state, built in the 1970s to producefast breeder reactor fuel.

Russia has a long history of development of MOX fuel for breeder reactors, but Minatom hadapparently not considered using MOX in LWRs until the U.S. plutonium disposition programcreated greater incentives to look at this option. If the fast reactor option were pursued, MOX fuelfabrication would take place at Mayak (near Chelyabinsk), where the partially-built Complex 300facility is located. If the water reactor option is pursued, plutonium conversion and MOX fuelfabrication facilities would be built at the RT-2 plant in Zheleznogorsk (Krasnoyarsk-26). (Seearticle on Russian MOX fuel fabrication.)

The joint study cites a number of safety precautions necessary in the fabrication of MOX fuelrelative to uranium fuel. MOX fuel emits higher gamma radiation and much higher neutron radiationthan uranium fuel. Therefore, a separate fresh fuel storage facility designed for MOX only fuelcontainers for on-site use, and transport equipment for fresh fuel may be necessary. Dust resultingfrom MOX fabrication is also a concern for worker safety because of the dangers of inhalingplutonium (see article on health effects of plutonium).

Reactor Options Under Consideration

The time it would take to convert plutonium into non-weapons-usable irradiated fuel in reactorsdepends on a number of factors:

the number, size, and type of reactors used

the average reactor power output

the percentage of plutonium in the MOX fuel

the percentage of the reactor core that is loaded with MOX fuel

It should be noted that all of the reactor options are widely expected to take considerably longerthan some vitrification options for meeting the goal of putting surplus plutonium into a non-weapons-usable form. In addition, the initial timeframe estimates for reactor options are likelyunderestimates. The options involving reactor construction are likely to take the longest.

Russia is considering using MOX fuel (a mixture of the oxides of plutonium and uranium) in bothfast reactors (also known as fast breeder reactors) and light water reactors (LWRs) for disposition,while the United States declared in December 1996 that it would pursue a "dual-track" strategy ofstudying the use of MOX in light water reactors as well as immobilization options that do not involvethe use of plutonium as a fuel at all.5 Although the U.S. contributed to the section of the joint reportwhich discusses MOX use in fast reactors, it will not pursue this option. The following sections lookat the main options for using LWRs and at Russian possible plans to use MOX in fast reactors.

Existing thermal reactors

The U.S. has a large number of operating reactors which could potentially be loaded with MOX.The Department of Energy has obtained expression of interest at one time or another from 18utilities offering 38 reactors for burning plutonium as MOX. Not all are currently interested, but thesituation is fluid. A formal process for utilities to develop proposals and for the Nuclear RegulatoryCommission (NRC) to license them to use MOX (if it believes the license applications to beappropriate) is underway.

Russia's options for plutonium disposition using existing thermal reactors are more limited. Forsafety reasons, the graphite-moderated RBMK reactors and small light water VVER-440 reactorshave been excluded from consideration. Only the larger LWR design, the VVER-1000, could beloaded with MOX, and only with a one-third MOX core (in other words, two-thirds of fuel rods in thereactor would be conventional uranium fuel, and the remaining one-third would be MOX). However,a 1995 report by the United States National Academy of Sciences (NAS) notes that even VVER-1000s "do not currently meet international safety standards,"6 and therefore must be upgradedprior to MOX use. A further complication is that Russia's seven operating VVER-1000 reactorswould not be able to consume 50 metric tons of surplus plutonium within the timeline of 20 to 40years set by the joint panels. In order to pursue a water reactor option, three partially-built VVER-1000 reactors in Kalinin and Rostov would need to be completed. Another proposal has been toload eleven VVER-1000 reactors in Ukraine with MOX fuel in addition to the Russian reactors.Other possible measures to shorten the time needed for disposition such as extending thereactors' operating lives beyond the currently foreseen 30 years, loading more than a one-thirdMOX core, increasing the plutonium content of the MOX (beyond the 3.9% current envisioned)would pose additional safety risks that have not been adequately addressed.

Even with a one-third MOX core, modifications will probably be necessary before VVER-1000scan be loaded with plutonium fuel. The joint report mentions several possible measures, most ofwhich are connected with maintaining reactor control (see below for further discussion of safetyissues). The timeline given in the joint report assumes the first VVER-1000 reactor would acceptMOX in 2001, and disposition (using 10 reactors with one-third MOX cores and a plutoniumcontent in the MOX of 3.9%) would be completed in 2028.

"Evolutionary reactors"

Both the U.S. and Russia are considering plans to use newer reactor designs that would be able totake a 100% MOX core because appropriate provisions have been made for additional control. Inthe U.S. three existing System-80 reactors of the Arizona Public Services Company located at PaloVerde could be used. Russia is also considering construction of up to five VVER-640 (NP-500)reactors (with instrumentation and control systems provided by Siemens). However, even if 100percent MOX cores were allowed in these reactors, the percentage of plutonium in the MOX wouldlikely be relatively low, so that a larger amount of MOX fuel would have to be fabricated. Hence theadvantages from the point of view of speed of disposition of such an approach may be relativelysmall. The joint report says that "it is believed" that the VVER-640s would be able to take a fullMOX core, with 3.7%.7

CANDU reactors

A third option considered by both the U.S. and Russia is the Canadian heavy water reactors (called"CANDU" reactors, which use natural uranium as fuel and heavy water as a moderator andcoolant). Unlike LWRs, which are shut down periodically for refueling, these reactors are continuallyfueled.

CANDU reactors would use 100 percent MOX cores. According to the Atomic Energy of CanadaLimited (AECL), CANDU reactors can use 100 percent MOX cores containing from 0.5 to 3percent plutonium without physical modification,8 but new licensing would be required because noCANDU reactors are currently licensed to use MOX fuel. CANDU reactors could accommodate100 percent MOX cores because they have adequate space for any additional control blades(similar to control rods) that may be needed.

CANDU reactors appear to have a number of significant advantages in the use of MOX fuel interms of controllability. The power production per unit of fuel would be higher with MOX fuel thanwith natural uranium fuel. With higher power production, the volume of high-level radioactive wasteproduced by these reactors would be smaller than that now produced by CANDU reactors.

Yet CANDU reactors also possess many disadvantages, such as the need for internationaltransport of MOX fuel, which can be chemically separated into uranium and weapons-usableplutonium in a relatively straightforward manner. Because CANDUs use small fuel bundles andhave the potential for on-line removal of fuel bundles (because they are continuously refueled),greater security against theft and diversion of plutonium is necessary. Use of CANDU reactors mayalso require production of a greater volume of MOX fuel than use of LWRs, since the fuel wouldcontain between 1.5 percent and 2.7 percent plutonium,9 rather than the 2.5 to 6.8 percent rangepossible in light water reactors (depending on the specific reactor).

Fast neutron reactors

The U.S. discontinued its fast reactor program (also called "breeder" reactors) due to their highcost and concerns over proliferation. However Minatom, because it views plutonium as an energytreasure, has continued extensive research into breeder reactors. Currently, Minatom is operatingone fast neutron reactor, the BN-600 at Beloyarsk, loaded with highly-enriched uranium fuel. Fouradditional fast neutron reactors have been planned, three at Mayak and one at Beloyarsk.Construction was started on two of these (one at each site) in the 1980s, but was halted in the early1990s because of lack of funds and local environmental opposition. Minatom has recently declaredits intention to resume construction and the projects are now undergoing licensing review, butfunding is still very uncertain.

Disposition of plutonium can be accomplished in a fast neutron reactor by removing the breedingblankets around the radius of the reactor core, thus turning the reactor from a plutonium producer, toa net burner (note that this does not mean that all of the plutonium is consumed, just that there maybe somewhat less in the spent fuel than in fresh fuel). Of course, one problem with breeder reactorsfrom a proliferation standpoint is that the uranium blanket can be inserted and used to make moreplutonium, including weapons-grade and super-grade plutonium.

Minatom proposes to build one BN-800 at Mayak for plutonium disposition. BN-800 reactors aredesigned to take 100% MOX cores, and joint report states that a BN-800 reactor could use 1.6metric tons of plutonium per year, thus completing disposition of 50 metric tons of plutonium in 30years. BN-800s are designed to take MOX with reactor-grade plutonium, but, based oncalculations that are two decades old, the report states that use of weapons-grade plutonium wouldnot significantly change reactor performance. A more recent and independent evaluation wouldappear to be needed in view of the seriousness of the issue.

Minatom also plans to complete construction of a second BN-800 at Beloyarsk which could befueled with MOX containing the approximately 30 metric tons of commercial plutonium which havealready been separated at the RT-1 plant at Mayak. This second reactor could serve as a backupfor plutonium disposition as well. The timeline given in the report foresees construction on the firstBN-800 to be completed by 2005, contingent on adequate financing, which has not yet beenarranged.

The joint report states that the existing BN-600 could be used as a demonstration reactor for MOXuse as early as the year 2000, assuming early funding for conversion and fuel fabrication facilities.However, the BN-600 is only able to handle a partial MOX core, and the report states thatadditional research would need to be conducted on the safety of using MOX fuel in this reactor withno radial breeding blanket. This reactor could consume about 0.5 metric tons per year, or about 5metric tons before the end of its operating life in 2010.

Disposition in breeder reactors poses a number of additional safety and proliferation risks. MOXfuel for fast reactors has a significantly higher plutonium content than fuel for LWRs. Because of thehigher plutonium content of the fuel, there would be additional plutonium in the spent fuel as well:breeder MOX spent fuel would have approximately 20% according to the report. Although Minatomdeclares the safety and environmental record of the BN-600 to be '"excellent," the report also notesthat about 30 sodium leaks have occurred in its first 14 years of operation. In addition, theinternational experience with fast breeder reactors has not been very positive. Safety and technicaloperating problems or accidents have resulted in the temporary or permanent shut downs of thistype of reactor in the United States, Japan, and France.

Light Water Reactor Safety and Licensing Issues related to MOX

The vast majority of LWRs were not designed to use plutonium as a fuel. While both plutonium-239and uranium-235 are fissile materials that generate similar amounts of energy per unit weight, thereare a number of differences between them as reactor fuels that affect reactor safety. The basic setof concerns relates to control of the reactor. The chain reaction in a reactor must be maintained witha great deal of precision. This control is achieved using control rods usually made of boron and (inpressurized water reactors) by adding boron to the water. Control rods allow for increases anddecreases in the levels of reactor power and for orderly reactor shut-down. They prevent runawaynuclear reactions that would result in catastrophic accidents.

It should be noted that while all commercial LWRs have some amount of plutonium in them which ismade during the course of reactor operation from uranium-238 in the fuel, the total amount ofplutonium is about one percent or less when low enriched uranium fuel is used. When MOX fuel isused, the total amount of plutonium would at all times be considerably higher. It is this differencethat creates most reactor control issues.10

Changing the fuel can affect the ability of the control rods to provide the needed amount of reactorcontrol and modifications to the reactor may be required before the new fuel can be used.Therefore, changing the fuel in any significant way also requires re-licensing of the reactor.

Several differences between the use of MOX fuel and uranium fuel affect safety:

The rate of fission of plutonium tends to increase with temperature. This can adversely affectreactor control and require compensating measures. This problem is greater with MOX madewith weapons-grade plutonium than that made with reactor-grade plutonium.

Reactor control depends on the small fraction of neutrons (called delayed neutrons) emittedseconds to minutes after fission of uranium or plutonium. Uranium-235 fission yields about0.65 percent delayed neutrons, but plutonium yields only about 0.2 percent delayed neutrons.This means that provisions must be made for increased control if plutonium fuel is used, ifpresent control levels and speeds are deemed inadequate.

Neutrons in reactors using plutonium fuel have a higher average energy than those in reactorsusing uranium fuel. This increases radiation damage to reactor parts.Plutonium captures neutrons with a higher probability than uranium. As a result, a greateramount of neutron absorbers are required to control the reactor.

The higher proportion of plutonium in the fuel would increase the release of plutonium andother transuranic elements to the environment in case of a severe accident.

Irradiated MOX fuel is thermally hotter than uranium fuel because larger quantities oftransuranic elements are produced during reactor operation when MOX fuel is used.

Overall, the issues related to reactor control, both during normal operation and emergencies, arethe most crucial. Most independent authorities have suggested that only about one third of the fuelin an LWR can be MOX, unless the reactor is specifically designed to use MOX fuel. However,there are some operational problems associated with using partial-MOX cores since MOX fuel isinterspersed with uranium fuel. Their differing characteristics regarding control, radiation andthermal energy mean that there are non-uniform conditions in the reactor that can render operationand control more complicated. Some reactor operators claim they can use 100 percent MOX coreswithout needing to make physical changes to the reactor or control rods. The safety implications ofsuch claims need to be independently verified.

The details of licensing procedure in the United States are well known. It is an elaborate, public andexpensive process that will almost certainly be contentious, as the joint report acknowledges.However, the role of Gosatomnadzor, the Russian nuclear regulatory agency, is not yet clear; nor isthe issue of whether it will have sufficient resources to assure a thorough licensing process. Thejoint report acknowledges that Gosatomnadzor has not yet begun considering MOX licensingissues, and public participation in the licensing process is also a question mark. The report givesno details about the Russian licensing process but says only that "all facilities are assumed to belicensed by appropriate national authorities."

MOX Spent Fuel

Plutonium is both used up and produced when MOX fuel is used in reactors. MOX spent fuelcontains more plutonium than conventional spent fuel (that is, spent fuel resulting from loading anLWR with low enriched uranium fuel). Conventional spent fuel from LWRs typically contains aboutone percent plutonium when it is withdrawn from the reactor. The amount of residual plutonium inMOX spent fuel would depend on the initial plutonium loading (percent of plutonium in the fuel), theburn-up of the fuel, and the configuration in which the fuel is used.

For light water reactors using MOX fuel, the NAS calculates that residual plutonium in the spent fuelwould range from 1.6 percent (for a 33% MOX core with 4% plutonium loading) to 4.9 percent (for a100% MOX core with 6.8% plutonium loading). Ranges of 2.5 percent to 6.8 percent plutoniumloading have been suggested. In the case of a CANDU reactor using a 100% MOX core, thepercentage of plutonium in MOX spent fuel would be between 0.8 and 1.4 percent for MOX fuelcontaining 1.2 percent and 2.1 percent plutonium, respectively.12

Repository disposal of MOX spent fuel is complicated not only by the higher plutonium content inMOX, but by the larger quantities of transuranic elements in the spent fuel as well. This results inMOX spent fuel being thermally hotter than conventional spent fuel. The presence of greateramounts of transuranic radionuclides like americium-241 also cause persistent higher spent fueltemperatures, and cause the decay of thermal power level to be slower. MOX spent fuel use maytherefore require that a host of issues be revisited, such as design of transportation and disposalcanisters, and design of on-site spent fuel storage casks. For instance, the higher temperaturesmay cause storage problems at reactors that have limited storage room in their spent fuel pools.The higher temperature may also result in a need for more repository space, unless a repository isdesigned to take hotter fuel and withstand higher temperatures. Greater repository space wouldresult in proportionally higher repository disposal costs. In addition, if the amount of residual galliumin MOX spent fuel is too high, it may result in deterioration of the spent fuel cladding, create newissues in evaluating the suitability of a repository, and pose greater risk of groundwatercontamination. There are some uncertainties as to the concentration of gallium that might adverselyaffect spent fuel integrity. The differences between spent MOX fuel and spent uranium fuel posemany complications for reprocessing as well.

Non-proliferation concerns

While much of the official discussion about MOX is that it would "burn" the plutonium, in realityplutonium is both consumed ("burned") and produced in nuclear reactors, as noted above.13 Themain function of plutonium disposition is not to get rid of all the plutonium. Rather it is to:

mix plutonium with other materials, usually very radioactive fission products, so that it wouldbe very difficult to re-extract for use in weapons; and

prevent diversion of plutonium by putting it into highly radioactive storage forms that would belethal to anyone wanting to steal it.

The joint report judges each plutonium disposition option on non-proliferation criteria, according toits timeliness, resistance to theft or diversion, and resistance to retrieval, extraction, or reuse. It wasagreed that in order to meet the timeliness goal, the options should provide for disposition of 50metric tons of plutonium within 20-40 years. The commonly-used yardstick to measure theresistance to theft and diversion of the final form of plutonium after disposition is the so-called"spent fuel standard." This criterion was identified by the NAS in their 1994 report, and means thatthe plutonium should be as inaccessible to theft, diversion, and re-extraction as plutonium in storedcommercial low-enriched spent fuel.

However, there is a major flaw in this standard when judging the long-term security of plutonium.The "spent fuel standard" inherently assumes that the plutonium will remain in spent fuel (orwhatever form it has been placed into)--that is, that it be slated for geologic disposal. However, thejoint report states that Russian policy does not allow for final burial of "plutonium-bearing materials"(which would include spent fuel), but rather the reextraction of plutonium through reprocessing.Minatom has stated very clearly on numerous occasions that it intends to reprocess spent MOXfuel, rendering the "spent fuel standard" effectively meaningless over the long-term. The U.S.appears to ready to allow Minatom to reprocess spent MOX fuel from the plutonium dispositionprogram. The joint report notes that ". . .Russia will ultimately recycle any plutonium left in the [MOX]fuel. The U.S. objective of plutonium disposition is satisfied when the isotopics of the weapons-grade plutonium have been altered by irradiation, the fuel attains a significant radiation barrier, andthe fuel is stored for several decades before reprocessing."14

Financial Issues

Even though plutonium will be used to generate electricity in nuclear reactors, the use of MOX fuelwill involve net costs. This is because it is more expensive to fabricate MOX fuel even when theplutonium is free than it is to purchase low-enriched uranium fuel, taking all costs, including rawmaterial costs, into account (for further discussion of costs see E&S #1). Using NAS estimates,MOX fuel costs for 50 metric tons of plutonium will be about $2 billion. If the plutonium content of theMOX is 5 percent, the excess costs for disposition of 50 metric tons of plutonium would be about$500 million for MOX fuel fabrication alone, compared to uranium fuel costs. The actual U.S. costsare likely to be far higher because utilities want subsidies to carry out the disposition mission andbecause many other uncertainties and delays are likely to raise costs.

Overall cost estimates in the U.S. and Russia differ because of differences in the structure ofreactor ownership and operation, and because of differing spent fuel policies. In addition to the fuelcosts themselves, there would be licensing costs for reactors, transportation and safeguard costs,and reactor construction and modification costs (if required). In general, Russian cost estimatesare less certain because of the rapidly-changing economic situation. Because of the policy toreprocess spent fuel, Russian cost estimates include only 50-year storage costs rather than thoseof final disposal.

Selected IEER plutonium publications:

Plutonium: Deadly Gold of the Nuclear Ageby IPPNW and IEER International Physicians Press, 1992 Price: $17. Also available in French,German, and Japanese.

Fissile Materials in a Glass, Darklyby Arjun Makhijani and Annie Makhijani IEER Press, 1995 Out of print: photocopy price: $5.Also available in Russian.

Return to E&S No.3 Main Page Return to E&S Homepage Return to IEER Homepage

Institute for Energy and Environmental Research

Comments to Outreach Coordinator: ieer@ieer.orgTakoma Park, Maryland, USA

December, 1997

ENDNOTES1. Almost 12 metric tons of this is non-weapons-grade plutonium produced in military plants.2. Joint United States/Russian Plutonium Disposition Study, September 1996, p. ExSum 2.3. Unless otherwise mentioned, technical aspects of the use of MOX fuel in reactors are from: Panel on Reactor-Related

Options for the Disposition of Excess Weapons Plutonium, Committee on International Security and Arms Control,Management and Disposition of Excess Weapons Plutonium: Reactor-Related Options, National Academy Press,Washington, DC, 1995.

4. Fabrication of lead test assemblies in Europe has been considered in order to allow MOX to be tested in reactorsbefore new fabrication facilities are built, but seems increasingly unlikely.

5. Unless otherwise mentioned, the facts regarding DOE's options are from: Storage and Disposition of Weapons-Usable Fissile Materials Final Programmatic Environmental Impact Statement: Summary, Office of Fissile MaterialsDisposition, U.S. Department of Energy, December 1996. Information on Russia's options is taken from the JointUnited States/Russian Plutonium Disposition Study, September 1996. Unfortunately, the report is available only inEnglish. The summary was published in Russian in mid-1997.

6. NAS 1995, p. 137.7. Joint Report, p. WR-27 - WR-29.8. By comparison, MOX fuel in an LWR core would range from one third to 100% of the core with a plutonium content of

2.5 to 6.8 percent.9. See NAS 1995, pp. 146-151, for a discussion of advantages and disadvantages of the use of CANDU reactors relative

to U.S. LWRs. The 1.5 to 2.7 percent range of MOX has been suggested by the reactor manufacturer.10. For more information on reactor control, see Science for Democratic Action, Vol. 5, No. 4, February 1997.11. NAS 1995, pp. 121-122.12. NAS 1995, p. 252, Table 6-1.13. Plutonium is formed in commercial reactors from the transmutation of uranium-238 under bombardment by neutrons.

14. Joint study, p. WR-36-37.

IEER ENERGY &SECURITY No. 3

Health Effects of PlutoniumBy Arjun Makhijani

Plutonium-239 is a very hazardous carcinogen which can also be used to make nuclear weapons. Thiscombination of properties makes it one of the most dangerous substances. Plutonium-239, while presentin only trace quantities in nature, has been made in large quantities in both military and commercialprograms in the last 50 years. Other more radioactive carcinogens do exist, like radium-226, but unlikeplutonium-239 cannot be used to make nuclear weapons, or are not available in quantity. Highly enricheduranium (HEU) can also be used to make nuclear weapons, but it is roughly one thousand times lessradioactive than plutonium-239. The danger is aggravated by the fact that plutonium-239 is relativelydifficult to detect once it is outside of secure, well-instrumented facilities, or once it has beenincorporated into the body. This is because its gamma ray emissions, which provide the easiest methodof detection of radionuclides, are relatively weak.

The main carcinogenic property of plutonium-239 arises from the energetic alpha radiation it emits.Alpha particles, being heavy, transfer their energy to other atoms and molecules within fewer collisionsthan the far lighter electrons which are the primary means of radiation damage for both gamma and betaradiation.1 Alpha particles travel only a short distance within living tissue, repeatedly bombarding thecells and tissue nearby. This results in far more biological damage for the same amount of energydeposited in living tissue. The relative effectiveness of various kinds of radiation in causing biologicaldamage is known as "relative biological effectiveness" (RBE). This varies according to the type ofradiation, its energy, and the organ of the body being irradiated. A simple factor, called quality factor, isused to indicate the relative danger of alpha, beta, gamma and neutron radiation for regulatory purposes.The International Commission on Radiation Protection currently recommends the use of a quality factor of20 for alpha radiation relative to gamma radiation.2

Once in the body, plutonium-239 is preferentially deposited in soft tissues, notably the liver, on bonesurfaces, in bone marrow and other non-calcified areas of the bone, as well as those areas of the bonethat do not contain cartilage. Deposition in bone marrow can have an especially harmful effect on theblood formation which takes place there. By contrast, radium-226, another alpha emitter, is chemicallyakin to calcium and so becomes deposited in the calcified areas of bones.

When it is outside the body, plutonium-239 is less dangerous than gamma-radiation sources. Sincealpha particles transfer their energy within a short distance, plutonium-239 near the body depositsessentially all of its energy in the outer dead layer of the skin, where it does not cause biological damage.

The gamma rays emitted due to plutonium-239 decay penetrate into the body, but as these are relativelyfew and weak, a considerable quantity of plutonium-239 would be necessary to yield substantial dosesfrom gamma radiation. Thus, plutonium-239 can be transported with minimal shielding, with no danger ofimmediate serious radiological effects. The greatest health danger from plutonium-239 is from inhalation,especially when it is in the common form of insoluble plutonium-239 oxide. Another danger is absorptionof plutonium into the blood stream through cuts and abrasions. The risk from absorption into the body viaingestion is generally much lower than that from inhalation, because plutonium is not easily absorbed bythe intestinal walls, and so most of it will be excreted.

The kind of damage that plutonium-239 inflicts and the likelihood with which it produces that damagedepend on the mode of incorporation of plutonium into the body, the chemical form of the plutonium andthe particle size. The usual modes of incorporation for members of the public are inhalation or ingestion.Plutonium may be ingested by accidental ingestion of plutonium-containing soil, or through eating anddrinking contaminated food and water. Incorporation via cuts is a hazard mainly for workers and (informer times) for personnel participating in the atmospheric nuclear testing program.

In general, plutonium in the form of large particles produces a smaller amount of biological damage, andtherefore poses a smaller risk of disease, than the same amount of plutonium divided up into smallerparticles. When large particles are inhaled, they tend to be trapped in the nasal hair; this prevents theirpassage into the lungs. Smaller particles get into the bronchial tubes and into the lungs, where they canbecome lodged, irradiating the surrounding tissue.

Other plutonium isotopes that emit alpha radiation, like plutonium-238, have similar health effects asplutonium-239, when considered per unit of radioactivity. But the radioactivity per unit weight variesaccording to the isotope. For instance, plutonium-238 is about 270 times more radioactive thanplutonium-239 per unit of weight.

Experimental data

The health effects of plutonium have been studied primarily by experiments done on laboratory animals.Some analyses have also been done on workers and non-worker populations exposed to plutonium

contamination. Measurements of burdens of plutonium using lung counters or whole-body counters,together with follow-up of exposed individuals, have provided information which is complementary toexperimental data and analysis. Experiments injecting human beings with plutonium were also done inthe United States. Between 1945 and 1947, 18 people were injected with plutonium in experiments usedto get data on plutonium metabolism. They were done without informed consent and have been the objectof considerable criticism since information about them became widely known in 1993.

Experiments on beagles have shown that a very small amount of plutonium in insoluble form will producelung cancer with near-one-hundred-percent probability. When this data is extrapolated to humans, thefigure for lethal lung burden of plutonium comes out to about 27 micrograms. Such an extrapolation fromanimals, of course, has some uncertainties. However, it is safe to assume that several tens ofmicrograms of plutonium-239 in the lung would greatly increase the risk of lung cancer. Larger quantitiesof plutonium will produce health problems in the short-term as well.

The precise quantitative effects of considerably lower quantities of plutonium are as yet not well known.This is due to several factors such as: the difficulty of measuring plutonium in the body; uncertaintiesregarding excretion rates and functions due to the large variation in such rates from one human being tothe next (so that the same body burden of plutonium would produce considerably different doses);complicating factors such as smoking; uncertainties in the data (as, for instance, about the time ofingestion or inhalation); differing and largely unknown exposure to other sources of carcinogens (bothradioactive and non-radioactive) over the long periods over which studies are conducted; failure to studyand follow-up on the health of workers who worked with plutonium in the nuclear weapons industry to theextent possible.

One of the few attempts to analyze the effects of microgram quantities of plutonium on exposed humansubjects was a long-term study of 26 "white male subjects" from the Manhattan Project exposed toplutonium at Los Alamos in 1944 and 1945, where the first nuclear weapons were made. These subjectshave been followed for a long period of time, with the health status of the subjects periodically published.The most recent results were published in a study in 1991.3

The amounts of plutonium deposited in the bodies of the subjects were estimated to range from "a low of110 Bq (3 nCi) ...up to 6960 Bq (188 nCi),"4 corresponding to a weight range of 0.043 micrograms to 3micrograms. However, weaknesses in the study resulted in considerable uncertainties about the amountand solubility of plutonium actually incorporated at the time of exposure.5

Of the seven deaths by 1990, one was due to a bone cance (bone sarcoma).6 Bone cancer is rare inhumans. The chances of it normally being observed in a group of 26 men over a 40-year timeframe is onthe order one in 100. Thus, its existence in a plutonium-exposed man (who received a plutonium dosebelow that of current radiation protection guidelines) is significant. 7 There are data for plutoniumexposure in other countries, notably in Russia. These are still in the process of being evaluated.Collaborative US-Russian studies are now beginning under the Joint Coordinating Committee onRadiation Effects Research (JCCRER) to assess the health effects of the Mayak plant to both workersand neighbors of the facility.

Return to E&S No.3 Main Page Return to E&S Homepage Return to IEER Homepage

Institute for Energy and Environmental Research

Comments to Outreach Coordinator: ieer@ieer.orgTakoma Park, Maryland, USA

December, 1997

ENDNOTES1. Gamma rays consist of high energy photons, which are "packets" or quanta of electromagnetic energy.

2. The energy deposited in a medium (per unit of mass) is measured in units of grays or rads (1 gray = 100 rads), whilethe biological damage is measured in sieverts or rems (1 sievert = 100 rems).

3. G.L.Voelz and J.N.P. Lawrence, "A 42-year medical follow-up of Manhattan project plutonium workers." HealthPhysics, Vol. 37, 1991, pp. 445-485.

4. Ibid., p. 186.

5. These aspects of the study are discussed in some detail in Gofman 1981, pp. 510-520 (based on the status of theManhattan Project workers study as published in Voelz 1979). See J.W. Gofman, Radiation and Human Health, (SanFrancisco: Sierra Club Books, 1991), p. 516.

6. Three of these deaths were due to lung cancer. It is difficult to assess the significance of this large percentage, sinceall three were smokers.

7. Voelz, p. 189.

**********************Yurika's E-mail Pu-Update****************** Herbert Scoville Jr. Peace Fellow Project Physicians for Social Responsibility FISSILE MATERIAL DISPOSITION & CIVIL USE OF PLUTONIUM Issue No. 4 November 26, 1996 ------------------------------------------------------------ CONTENTS Main Story: TECHNICAL ASPECTS OF MOX FUEL IN LIGHT WATER REACTORS/THE REACTOR OPTION 1. How Does It Work ? Major Differences From Conventional LWRs 2. Will MOX Option Really Eliminate Plutonium? 3. Impacts on Radioactive Waste Management? 4. The Health and Environmental Effects of the Use of MOX NEWS BRIEFS *G7 Paris Summit Report *Reprocessing Back in the US? *Plutonium Inventory of the World, Update *International MOX Assessment *****************************************************************Main Story: TECHNICAL ASPECTS OF MOX FUEL IN LIGHT WATERREACTORS (LWR)/ THE REACTOR OPTION

1. How Does It Work? Major Differences From Conventional LWRs

Proponents of burning plutonium in mixed-oxide(MOX) fuel in LWRsoften say that since plutonium already exists in the burneduranium fuel and is still burning, there will not be a bigdifference by increasing the amount of plutonium a little bit. The fact is that great effort is put to make it "not a bigdifference."

In conventional LWRs, the uranium fuel has about 3% fissileuranium-235 and the rest is non-fissile uranium-238. Whenfissile uranium absorbs a neutron, it starts fissioning andreleases energy, emitting several neutrons. One neutron willlikely start another fission, creating a chain reaction, but theother neutrons must be controlled so that it will not make amassive reaction which will induce an uncontrolled chainreaction. Control rods are designed to absorb the extra neutrons. But some neutrons are also absorbed by the non-fissileuranium-238 and this decays into fissile plutonium-239.

In the beginning, the plutonium content is zero and the fissileuranium is about 3%. The fissile uranium decreases as they burn,creating plutonium at the same time. At the end of one reactorcycle, the content of fissile uranium is about 0.7%-0.8%, approximately equal to the content of fissile plutonium-239 thatis created.(1)

In the case of MOX fuel used in one-third of a LWR core, theplutonium content is roughly 4% from the beginning, which isapproximately 5 times more than that in the end of one cycle of auranium fuel. This is a significant difference in terms ofcore nuclear physics.(2)

In a fast reactor, plutonium content of MOX fuel can be up to50%. In the option to burn plutonium in CANDU reactors, the MOXfuel content could be 100% core.(3) But this has not beentested, nor is there any experience at all of burning plutoniumfuel in CANDU reactors.

All light water reactors are designed to burn uranium fuel. Thus the nuclear physics of MOX fuels must be adapted to be assimilar as possible to that of uranium fuel. The MOX fuelassemblies should be able to be operated as uranium assemblieswithout any restriction to the level of power, performance orsafety.

#Various Types of Fuel Assemblies Necessary To Burn MOX

In order to achieve the same performance as normal LWR, the fuelassemblies are made into various types with different plutonium and uranium contents. Usually, MOX fuel assembly designs forpressurized water reactors use three types of plutonium contents,1.9%, 2.3% and 3.3%.(4) For boiling water reactors, four to sixdifferent plutonium contents designs are used.(5) Anotherdifference is that, because of the intensity of plutonium'sthermal energy, plutonium fuel pellets cannot be of the same formas uranium fuel. It could be in the form of a donut where thecentral part is void to let the heat dissipate. But this type of

a fuel pellet is likely to collapse.(6) All these factors makethe fuel production extremely complicated and difficult, comparedto the one-standard uranium fuel for conventional LWRs.

#Reduced Efficacy of Control Rods

Control rods work by absorbing neutrons in the reactor core, somaintaining stable power conditions. Criticality depends on thesmall fraction of neutrons produced in the fission of uranium orplutonium which are generated with a delay of about tenseconds.(7) This time difference makes it possible to controlthe power level by mechanically inserting additional control rodsinto the core. However, the fraction of delayed-neutrons in Pu-239 is about one-third that of uranium-235, which means that the reactor is moresensitive to variations in power.(8) In addition, plutoniumhas a slightly higher propensity to capture thermal neutrons thanuranium. Therefore the efficacy of control rods is somewhatreduced, and safety margins are lower. The additional demands oncontrol systems are largest for those plutonium fuels in whichplutonium-239 content is highest, as in MOX fuel using weapon-grade plutonium.(9) For these reasons, the MOX fuel assembliesshould be placed away from the control rods.

The higher average energy of the neutron spectrum of MOX alsoincreases the rate of radiation damage to structural materials inand around the core. This could cause embrittlement of thereactor vessel in the end, which is another factor for safetyconcerns.

#Danger of Losing Control of the Reactor Is Greater with MOX

Conventional LWRs are designed to decrease the reactivity whenthe temperature rises. But when using Pu-239 as fuel, heating ofthe core from an increase in reaction rate tends to increase thereaction rate still further. This is called the positivetemperature coefficient of reactivity, meaning there is a dangerof losing control of the reactor by accelerated chain reaction offissioning.(10)----------------------------------------------------------------(1)"Han-Genpatu Demae Shimasu," Jinzaburo Takagi (Nanatsumori-Shokan, 1993, p.216)(2) Ibid. pp.216-217(3)Draft Nonproliferation and Arms Control Assessment of Weapons-Usable Fissile Material Storage and Plutonium DispositionAlternatives (US Department of Energy, October 1, 1996, p.93)(4)"Options for Plutonium," by E.R. Merz(Research Center Julich)for the International Seminar on MOX Fuel (June, 1996, UK)(5)Ibid(6)Ibid note (1) p.218(7)"Disposition of Separated Plutonium" Frans Berkhout, Frank vonHippel, et.al. (Science and Global Security, 1993 Vol.3, p.177)(8)"Management and Disposition of Excess Weapons Plutonium,Reactor-Related Options (National Academy of Sciences, 1995,p.41)(9) Ibid(10)Ibid. p.42================================================================

2. Will MOX Option Really Eliminate Plutonium?

Three options for the disposition of "excess" plutonium are considered. They are the "reactor option," burning it as MOXfuel in reactors; "immobilization", mixing plutonium with highlyradioactive fission products and glassifying it into logs forgeological disposal; and "deep borehole," burying plutonium deepenough so that it will be unretrievable.

The proponents of the reactor option using MOX fuel often saythat the immobilization and the deep borehole options will merelyput the plutonium underground and will not eliminate plutonium. They claim that the only way to eliminate plutonium is to burn itin reactors. But this is misleading. It can only be eliminatedby repeatedly reprocessing the spent MOX fuel, and reusing theseparated plutonium. But plutonium from reprocessed MOX spentfuel is degraded in quality and cannot be used as fuel. Thescale of effort required to overcome the economics and thetechnological difficulties is overwhelming.

The objective of burning excess plutonium in reactors is toconvert the weapons-grade plutonium into spent fuel, contaminatedwith other highly radioactive fission products so that it will bedifficult to retrieve plutonium without reprocessing. This iscalled the "spent fuel standard." But even if it becomes "spentfuel standard," plutonium could be retrieved by reprocessing, and

studies have shown that nuclear bombs could be made from suchseparated "reactor-grade" plutonium.(11)

The real amount of plutonium will decrease by half by burning itas MOX fuel in LWRs. The MOX fuel starts with 4% plutonium and96% uranium-238. By the end of one fuel cycle, 2% plutonium willremain in the spent MOX fuel together with 94% uranium and 4%fission products.(12) According to National Academy of Sciences,out of the 50 tons of "excess" weapons plutonium, a substantialamount of plutonium would remain in the spent MOX fuel, between10 to 40 tons(13) depending on how long the fuel remains in thereactor core and the percentage of MOX the core use. -------------------------------------------------------------(11) Draft Nonproliferation And Arms Control Assessment ofWeapons-Usable Fissile Material Storage and Plutonium DispositionAlternatives (US Department of Energy, October 1, 1996, pp.34-36)(12)Notes by Dr. Arjun Makhijani (IEER, November 20, 1996)(13)Management and Disposition of Excess Weapons Plutonium(National Academy of Sciences, 1994, p.155)===============================================================

3. Impacts on Radioactive Waste Management

MOX spent fuel contains more fission products than uranium spentfuel. The important factor in managing spent fuel is the heatgeneration caused by the highly radioactive fission products.Since spent MOX fuel contains much more fission products, theheat generation from MOX spent fuel is twice as high as that ofspent uranium fuel after 10 years and three times as high after100 years.(14)

What this means is that less spent MOX fuel could be put in alimited repository site, leading to the necessity of more orlarger repository sites. Or, longer periods of centuries forinterim storage would be necessary. Because of the existence ofmore plutonium, there is a criticality concern for geologicrepository, and requires separate licenses for disposal. Thismeans additional costs and delays. In other words, spent MOXfuel disposal will require more space, more time, and moresubstantial costs.

Another typical argument proponents of plutonium "recycling"raise is that the extent of uranium mining, milling, conversion,enrichment and fabrication will be reduced, and thus curb theamount of related radioactive waste as a whole. This argumentignores the additional waste produced by fabricating MOX fuel,burning in LWRs and the effects of making spent MOX fuel disposalmore difficult, not to forget the huge waste produced byreprocessing (which is unnecessary only in the case ofdisposition of weapons plutonium). -----------------------------------------------------------------(14)"The MOX Industry or The Civilian Use of Plutonium," C.Kueppers & M. Sailer (IPPNW, 1994, p.64)================================================================

4. The Health and Environmental Effects of the Use of MOX

#Specific Dangers of Plutonium

Plutonium does not exist in the natural environment, and is onlyproduced in nuclear reactors. It is known as one of the mosttoxic elements. It emits high energy alpha radiation, and hasharmful biological effects. Alpha radiation has a very short range but very intenseionization power. If exposed on the surface of the skin, theskin works as a shield and will prevent its penetration into thebody, but all of its ionizing power will be focused on the smallspot, causing burns and killing the skin tissue. If inhaledinto the body, the alpha particle will go in through therespiratory tract, and enter the lung. Due to its longhalf-life, it will stay in the body permanently, emitting alpharadiation, and killing the surrounding tissues by strongionization. If plutonium is taken into the body in soluble form(e.g. plutonium nitrate) through food chain, it will enter theblood stream, and into the bones, liver and genital organs whereit will be enriched. Alpha radiation leads to reactions in thecells of living things. It can cause damage to the nucleus andDNA of the cell, in effect causing genetic damage in descendants,particularly if germ cells are affected.(15)

#Dangers of Resuspension in the Environment

In the event of a contamination of the environment withplutonium, the whirling up and inhalation of plutonium particles,

known as resuspension, plays an important role. If there is aroad traffic, building work or cleaning work at the plutoniumcontaminated site, plutonium can enter the body through therespiratory tract. Generally, the more whirled up, the greaterthe dose intake per quantity of plutonium on the ground. Ifthere is fire, and plutonium becomes airborne into fine aerosolparticles, plutonium contamination of the environment will extendto a far larger scale, landing on ground, contaminating a vastwider area. Plutonium remains effective over very long periodsaffecting the health of the people and the environment.(16)

#Accident Scenario When Burning MOX

Accidents involving overheating and meltdown are possible in anynuclear reactors. In such accidents, not only would readilyvolatile noble gases, like iodine and caesium be releasedto the environment, but a small portion of the actinides,including plutonium and neptunium would be released. As theactivity of the actinides is substantially higher in the case ofMOX, the consequences of such severe accidents become moreserious.

When MOX fuels are used, the probability of having such seriousaccidents or trouble would increase due to the high content ofplutonium in the fuel. Even if an accident is not a serious one,it could become serious since even a small portion of theinventory of actinides released to the environment could causesignificant radiological consequences.

According to a comparative analysis of possible consequences of acore meltdown accident in the German Kruemmel nuclear power plantwith and without the use of MOX fuel(17):*The radiation exposure from inhalation of radioactive materialsduring the passage of the radioactive cloud is higher by severaldozen percent than if uranium fuel elements were exclusivelyused.*Radiation exposure through the route of inhalation ofremobilized long-lived actinide isotopes is more than doubled.*The land areas to become out of use by long-term contaminationincreases as the resuspension pathway is a limiting factor andthe greater part of the dose resulting from the pathway comesfrom the actinides.(18)

#Accidents at Fabrication Plants

Accidents at MOX fuel fabrication plants have occurred. In June,1991, the storage bunker of the MOX fuel fabrication plant inHanau, Germany was contaminated with MOX. It occurred after therupture of a foil for container packaging in the course of anin-plant transportation process. Five workers were exposed toplutonium. This accident was the main reason the fabricationplant at Hanau was shut down.(19)

In November, 1992, a rod was broken through a handling error andMOX dust released during the mounting of MOX fuel rods to fuelassemblies in the fuel fabrication facility adjoining the MOXfacility in Dessel, Belgium.(20)

In event of such accidents, if the International Commission onRadiological Protection (ICRP) recommendations for general publicexposure were adhered to, only about 1 mg of plutonium may bereleased from a MOX facility to the environment. As acomparison, in uranium fabrication facility, 2kg (2,000,000mg)ofuranium could be released in the same radiation exposure. A 1 mgrelease of plutonium from a processing process can easily happenfrom various smaller incidents.(21)

#Worker Hazards

The National Academy of Sciences concludes that the mainenvironment, safety and health related issues in weaponsplutonium disposition that needs special attention with theaddition of weapons plutonium is the occupational risk from fuelpreparation. (22)

Because plutonium is more radioactive than uranium, greatersafety concern is required when handling the material in whateverway. The ICRP sets a standard for occupational exposure toradiation at 100 mSv over 5 years, with a maximum of 50 mSv inany one year. If you interpret this in comparison for workers atan uranium fuel fabrication plant with MOX fuel fabrication plantworkers, the standards for protection against inhalation areroughly two Million times stricter in plutonium processing thanin uranium processing.(23)

Another factor is the gamma radiation exposure which comes fromamericium, which accumulates as plutonium decays into americiumas time lapses. Gamma radiation penetrates through almostanything, so it is very difficult to protect workers from thisradiation. --------------------------------------------------------------(15)"The MOX Industry or The Civilian Use of Plutonium," C.Kueppers & M. Sailer (IPPNW,1994,pp.16-19)(16)Ibid(17)"The Consequences of Severe Accidents in the Kruemmel NuclearPower Plant for the Territory of the City of Hamburg and theEffects of Disaster Control Measures (Oko Institut, April 1992)(18)Ibid. note (15), pp.48-50(19) Ibid note (15) p.40(20) Ibid. (21) Ibid. (22)"Management and Disposition of Excess Weapons Plutonium,Reactor-Related Options"(National Academy of Sciences, 1995,p.97)(23)Ibid. note (15) p.38 ================================================================NEWS BRIEFS

>>G7 Paris Summit Report

On October 28-31, government officials and experts of the G7countries plus Russia, Belgium, Switzerland, International AtomicEnergy Agency (IAEA) and European Commission gathered in Parisand discussed military plutonium disposition options. Thedelegations included nuclear fuel cycle companies such as COGEMAof France, BNFL of UK, Belgonucleaire of Belgium, Atomic Energyof Canada Limited, SIEMENS of Germany, and utilities such asTokyo Electric of Japan, and Nordostschweizerische Kraftwerke AGof Switzerland. They concluded that both burning in reactors(MOX) and immobilization should be pursued in parallel and theyare not mutually exclusive. The proposal from Russia, Germanyand France to build a pilot scale MOX fabrication plant in Russiais said to be close to fruition and welcomed by the participantsincluding US.

However, it was stressed by the US that the new MOX fabricationfacility should not be used for any other purposes except for thedisposition mission and that the spent MOX fuel not be recycled. The US maintained that it can support a large-scale Russian MOXprogram "only on the basis that it's not part of a reprocessingeconomy in Russia." Russia was obviously adamant in refusingthese conditions stating that they did not want to accept anyposition that could be seen as restricting their options in thefuture.

The New York Times reported on November 22 that the US DOEis ready to announce the Record of Decision to choose the reactoroption. On November 12, the Japanese press reported Japan willcooperate in the construction of a MOX fabrication plant inRussia, as the US have approved of the plan as well.(24) Thedomino effect of endorsing the "reactor option" is alreadystarting. But as the New York Times concluded, the "decisivebattle will take place years from now, in localities withelectric companies that agree to accept mixed oxide fuels."

(Sources: Nuclear Fuel 11/4/96, Nucleonics Week 11/7/96, SpentFuel 11/4/96)(24) Asahi Shimbun, Nov.12,1996, Denki (Electric) Shimbun,Nov.12, 1996--------------------------------------------------------------->>Reprocessing Back in the US?

On November 12, Gregg Renkes, a staff director of the SenateNatural Resources Committee of the United States, said during apanel discussion at the American Nuclear Society Convention thata provision advocating overseas reprocessing of US waste will beincluded in the comprehensive nuclear waste legislation to beintroduced in the 105th Congress (beginning in early 1997). Spent nuclear fuel and high level radioactive waste are piling upat reactor sites as well as DOE weapons facilities in the US. Renkes claimed that the waste problem US faces today is theresult of an "ostrich nuclear policy," keeping heads in the sand,ignoring that the so-called "nuclear fuel cycle back-end policy"is "broken." A reprocessing option was introduced as vague language in theSenate Waste Bill S1271 of 1995. As an "Emergency Relief"measure, if a utility "has exhausted its existing on-site storagecapacity," the utility could contract with "entities qualified toprovide interim storage and conditioning." The euphemistic term

"conditioning" means "reprocessing." However, when S1271 wasrevised to S1936 in the early summer of 1996, the EmergencyRelief provision was dropped. S1936 passed the Senate on July31, 1996. The House version of the same bill contained noreprocessing language. But under the threat of a Presidentialveto, the Republican leadership in the House declined to pushthis bill through in the election year. As a result, there is nolegislation for interim storage at the moment.

(Sources: Nuclear Fuel 7/15/96, Nucleonics Week 11/14/96, "USHigh-level Waste Management Policy and the Reprocessing Option"by Gregg Renkes, "Long Battle Over Yucca Site May Be Coming to aClose," Government & Commerce, November 18, 1995)------------------------------------------------------------>>Plutonium Inventory of the World, Update

At the Reprocessing Working Group meeting held on October 4-5,in Washington, DC, Dr. Frans Berkhout of the University ofSussex in England gave the latest figures on world plutoniuminventory. It will be announced in the new version of the "WorldInventory of Plutonium and Highly Enriched Uranium 1992"(25)scheduled to be published in January 1997.

According to Dr. Berkhout, the military stockpile is 250 tons,whereas the civilian plutonium is 990 tons as of end of 1995. Ofthe civilian plutonium, 800 tons is in spent fuel, 141 tonsseparated and stockpiled, and 49 tons recycled. Of the 49 tonsrecycled, 21 tons is in fast reactors and 28 tons in light waterreactors in the MOX programs.

(25)"Plutonium and Highly Enriched Uranium 1996: WorldInventories, Capabilities and Policies," Oxford UniversityPress/Stockholm International Peace Research Institute, 1997------------------------------------------------------------>>International MOX Assessment

An International MOX Assessment ("A Comprehensive Social ImpactAssessment of MOX Use in Light Water Reactors") is beingconducted by experts around the world headed and sponsored byCitizens' Nuclear Information Center in Tokyo. In lack of acomprehensive in-depth assessment focused on MOX use in LWRs, theproject is intended to be the first such independent,comprehensive study on MOX. The experts include J. Takagi(Japan), M. Schneider(France), I. Hokimoto (Japan), M. Sailer(Germany) and F. Barnaby(UK). The interim report was publishedon October 26, 1996 in Kyoto, Japan. The report is availablefrom CNIC (Tel:81-3-5330-9520, Fax:81-3-5330-9530,E-mail:cnic-jp@po.iijnet.or.jp).*****************************************************************Thanks to Kathryn Schultz of Center for Defense Information, thePu-Updates are available on CDI's Home Page on the Web at<http://www.cdi.org> under Fissile Materials in the Issuessection.****************************************************************For information or comments, subscription, or for previousissues, please contact Yurika Ayukawa at 202-898-0150 Ext.226,fax 202-898-0172, or e-mail <yayukawa@igc.apc.org>.