Used Nuclear Fuel:Handled

With Care

How the nuclear energy industry manages used fuel on site

Nuclear Power Plant

Dry Storage Site

Q. What is on-site, dry storage?A. On-site storage systemsinvolve sealing used nuclearpower plant fuel in massive, air-tight steel or concrete-and-steel canisters that provide bothstructural strength and radiationshielding. All storage canis-ters—which can hold seven to68 twelve-foot-long used fuelassemblies—are naturally cooledand ventilated (they involve nomechanical devices for coolingor ventilation) and are built towithstand natural disasters suchas tornadoes and earthquakes.They are placed upright on athree-foot-thick concrete pad orhorizontally in a steel-reinforcedconcrete vault.

oday, more than 100 nuclearpower plants contribute nearly20 percent of the electricity

generated in the United States—cleanly, with no air pollution.

A byproduct of nuclear-generated elec-tricity production is radioactive usednuclear fuel. The U.S. nuclear energyindustry has safely managed used fuelfor decades, carefully containing it fromrelease to the environment. When thefederal government takes over responsi-bility of this material, the safe manage-ment of used nuclear fuel will be con-tinued by the Department of Energy.

What Is Used Nuclear Fuel?To generate electricity, nuclear powerplants use uranium oxide. This solidfuel—in the form of small ceramic pel-lets—is placed inside metal fuel rods,which are grouped into bundles calledassemblies.

Fission—which involves the splitting ofuranium atoms in a chain reaction,rather than the burning of fossil fuels—produces a tremendous amount of heatenergy that is used to boil water into

steam. That steam, in turn, drives a tur-bine-generator to produce electricity,which is sent across power lines tohomes, businesses and schools.

Over time, the energy in a nuclearplant’s fuel is consumed, and every 12-24 months the plant is shut downand the oldest fuel assemblies areremoved and replaced by new ones.

Fuel Pellet and Rod (actual size)

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Those assemblies, in the process ofgenerating enormous amounts of ener-gy, have become intensely radioactiveas a result of the fission process. Butcontrary to what you see in fictionalmovies or television programs, thisused fuel is carefully shielded and safely managed at the plant sites. It is solid and compact, and relativelysmall in volume.

At most plants, used fuel is stored insteel-lined, concrete vaults filled withwater. In these used fuel pools, thewater acts as a natural barrier for radiation from the fuel assemblies.

The water also keeps the fuel coolwhile the fuel decays—becomes lessradioactive. The water itself neverleaves the inside of the power plant’sconcrete building.

Nuclear power plants were designed tostore at least a decade’s worth of usedfuel. Some plants soon will—or alreadyhave—run out of used fuel pool capaci-ty. The federal government was to beginmoving used fuel from plant sites in1998, as mandated by the

Nuclear Waste Policy Act of 1982, but itis running behind in its waste manage-ment program.

It now appears the government maynot begin to remove used fuel before apermanent repository opens or is nearcompletion—sometime around 2007.

Many nuclear companies are usingabove-ground, dry storage facilities to expand on-site storage capacity.

Nuclear power plants store used fuelin steel-lined concrete pools.

Q. How long can used fuel bestored safely on site?A. The Nuclear RegulatoryCommission has determinedthat used nuclear fuel can bestored safely and with minimalenvironmental impact—eitherin used fuel pools or in above-ground containers—for at least30 years beyond the licensedoperating life of a nuclearpower plant.

The NRC must approve everycontainer design. Its regulationscover testing, manufacturingand maintenance.

Fuel Assembly Dry Storage Canister

The used fuel is transferred fromthe water-filled storage pool to a drycanister for on-site storage and even-tual transport to a federal repository.

monitored

he delay of a federal repositoryor other centralized storage facil-ity means that nuclear power

plants must store more used fuel thanexpected and longer than originallyintended. By 2010, the earliest openingdate for a repository, 78 power plantswill find themselves with no room leftin their used fuel pools.

Safeguards Are Integral to Dry Storage SystemsSince 1986, more than a dozen U.S.plants—including several shutdownunits—have supplemented their storagecapacity by building above-ground, drystorage facilities known as IndependentSpent Fuel Storage Installations. Othercountries also have safely and success-fully stored used fuel above groundsince the mid-1970s.

Above-ground storage systems—likeused fuel pools—incorporate a numberof safeguards to protect public healthand safety.

The foremost safety feature is the con-struction of the containers: steel or steel-reinforced concrete, 18 or more

inches thick. Not only are the contain-ers extremely rugged, materials likesteel, concrete and lead serve as aproven, effective radiation shield. Eachcontainer—depending on the design—can hold from seven to 68 twelve-foot-long used fuel assemblies. Once loaded,the containers are stored horizontally ina concrete vault, or they stand upright on a three-foot-thick concrete pad. By mid-1999, nearly 150 of these con-tainers were being used safely atU.S. nuclear power plant sites.

Dry storage containers aredesigned and tested to preventthe release of radioactivity underthe most extreme conditions—earthquakes, tornadoes, hurri-canes, floods and sabotage. All ofthe designs are naturally cooledand ventilated. No mechanicaldevices are needed.

To further ensure public health andsafety, each container design must beapproved by the Nuclear Regulatory

Commission. While the NRC has deter-mined that used fuel can be stored atplant sites without adverse health orsafety consequences for at least 30years beyond the licensed operating lifeof a nuclear power plant, the agencyrequires that dry storage containers beconstantly monitored and relicensedevery 20 years.

Dry storage containers are constantly and inspected regularly bynuclear plant personnel.

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t each of America’s nuclearpower plants, public health andsafety are paramount—from the

plants’ conservative design with multi-ple barriers and backup operating sys-tems to continual training and testingof the people who run the plants.

Used Fuel ManagementPreserves Nuclear Energy’sBenefitsNuclear power plants are the nation’slargest source of emission-free electrici-ty. No other source of electricity in theUnited States contributes such a largeshare of energy production while havingsuch a limited environmental impact.

Just as important, as America’s second-leading source of electricity, U.S.nuclear plants play a significant role inimproving people’s lives—whether it’spowering offices and factories or provid-ing the light for a bedtime story.

Performance measures tracked since1980 show that these plants continue toimprove their safety and performancerecords. Used fuel management practicesalso clearly demonstrate the nuclearindustry’s concern for public health andsafety.

Plant operators are committed to man-age the nation’s used nuclear fuel safelyand responsibly until the federal gov-ernment opens a centralized repository.Doing so not only protects public healthand safety, it also ensures that Amer-icans can enjoy the benefits of reliable,economical and emission-free nuclearenergy.

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Centralized Storage Will HoldDown Costs to ConsumersWhile the use of above-ground, dry stor-age allows the nation’s nuclear powerplants to continue providing reliable,

economical and emission-free electricityto millions of Americans, these systemsare expensive.

Depending on the design, a container’scost can range from $500,000 to morethan $1 million. Some nuclear plantswill need dozens of these containersuntil the federal government opens acentralized used fuel management facili-ty. Consumers of nuclear-generated elec-tricity will have to foot the bill forthese on-site storage systems, eventhough they were never envisioned inthe Nuclear Waste Policy Act of 1982.There’s one other reason a centralized

facility is needed: Nuclear powerplants—while carefully and safely managing used fuel for more than threedecades—were never built for long-termstorage. Experts agree that moving usedfuel to a single facility—built specifical-ly for that purpose—will lessen the costto the public while improving on analready excellent safety record.

Until a centralized facility opens, nu-clear utilities will continue to use drystorage systems that are subject to thesame rigorous safety standards and reg-ulatory oversight as every other aspectof nuclear power plant operations.

Suite 4001776 I Street, NWWashington, DC 20006-3708

Phone 202.739.8000Fax 202.785.4019www.nei.org

GP0035October 1999