Alternate Route
U.S. Department of Transportation rules for the routing of Yucca
Mountain shipments require that such shipments travel on Interstates
unless an impacted State designates an "Alternate Route" (a route to be
used in lieu of an Interstate). Sections of California State Routes
127, 178 and/or 190 could feasibly be designated by the State of
California as part of an Alternate Route.
High-Level Nuclear Waste
Primarily nuclear waste
originating from the development and manufacturing of nuclear weapons.
Most High-Level Nuclear Waste slated for Yucca Mountain will be in the
form of radioactive glass logs encased in metal cylinders.
Spent Fuel
Used fuel rods discharged from commercial nuclear power reactors.
Transuranic Nuclear Waste
Radioactive waste produced at federal facilities during research and
production of nuclear weapons. These wastes include protective
clothing, laboratory tools and equipment, debris, rags, glass, and
soils that are contaminated with small amounts of radioactive
materials, such as plutonium and americium. They also may contain small
amounts of hazardous chemicals.
Low-Level Nuclear Waste
Any radioactive waste that is not spent nuclear fuel, high-level waste,
transuranic waste, mixed-waste or uranium-mill tailings. It is produced
by virtually every process involving radioactive materials. Low-level
waste spans a wide range of characteristics, but most of it contains
small amounts of radioactivity in large volumes of material.
Advanced Burner Reactor
A new type of nuclear reactor that accepts recycled nuclear fuel and
consumes more transuranic elements than it creates, while generating
electricity. It typically belongs to the class of nuclear power plants
called "fast reactors." "Burn" does not mean incinerate or combust, it
means to transmute or convert transuranics into shorter-lived isotopes.
Advanced Fuel Cycle Facility
A multi-purpose research and development laboratory to serve fuel cycle
testing needs for the next 50 years or more.
Advanced Fuel Cycle Initiative
The mission of the current Advanced Fuel Cycle Initiative (AFCI) is to
develop proliferation-resistant spent nuclear fuel treatment and transmutation
technologies to enable a transition from the current once-through nuclear fuel
cycle to a future sustainable, closed nuclear fuel cycle where valuable material
is separated from waste and recycled, whereby extracting energy and reducing
waste.
Advanced Simulation Laboratory
A laboratory to support robust research, computer simulation and
visualization, reducing the cost of future experiments by state-of-the-art
computer simulation of relevant chemical and physical processes.
Atom
At atom is the basic component of matter; all matter is divided into one
hundred different chemical element having all the chemical properties of the
element.
Closed Fuel Cycle
An approach to handling used nuclear fuel in which useful parts of used
nuclear fuel are recycled; also called "recycle" fuel cycle, in contrast with
the "throw away" or "open" fuel cycle.
Energy Security
A reliable supply of affordable energy.
Enrichment
The physical process of increasing the proportion of isotope uramium-235 to
uranium-238 to make the mixture more usable as nuclear fuel.
Enriched Uranium
Uranium in which the proportion of uranium-235 (to uranium-238) has been
increased above the natural 0.7 percent uranium-235. Reactor-grade uranium
is usually enriched to three to five percent uranium-235. Uranium can be
fabricated into nuclear fuel and fissioned in nuclear reactor to produce energy.
Engineering Scale Demonstration
Demonstration of the steps of a technology on a scale sufficient to obtain
cost and performance data required to support potential subsequent
commercialization of the technology.
Fast Reactor (fast spectrum reactor)
A nuclear reactor that can extract energy via fission from all types of
uranium, including depleted uranium, which is otherwise waste from enrichment,
and all isotopes of the transuranic elements. Neutrons are kept at higher
average energy in a fast reactor than in a thermal reactor; these higher energy
neutrons are able to fission more isotopes. contrast with "thermal
reactor."
Fission
The splitting of an atom into at least two other atoms and the release of a
relatively large amount of energy. Two or three neutrons are usually
released during this type of transformation.
Fission Product
The atoms (fission fragments) formed by the fission of heavy elements such
as uranium.
Open Fuel Cycle
Nuclear fuel is used once in a nuclear power plant and then thrown away;
also called "throw away" or "once-through" fuel cycle. Contrast with
"recycle or closed fuel cycle."
Plutonium
An artificial radioactive isotope that can be fabricated into nuclear fuel
and fissioned in a reactor to produce energy. Some plutonium isotopes also
can be used in nuclear weapons.. Others can't.
Proliferation
The spread of nuclear weapon materials and/or technologies.
PUREX (Plutonium Uranium Extraction)
An older technology for separating used nuclear fuel into components that
produce both pure plutonium and uranium, all else is waste. The separation
uses a water-based acid dissolution of the used nuclear fuel. Contrast
with UREX+.
Pyroprocessing
A technology for separating used nuclear fuel into components that separates
uranium, but keeps all the transuranic elements together. The separation
uses a molten chloride salt to dissolve the used nuclear fuel, rather that
water-based acid as is used in PUREX and UREX+.
Radioisotope
An unstable isotope of an element that decays or disintegrates
spontaneously, emitting radiation. Approximately 5,000 natural and
artificial radioisotopes have been identified.
Reactor
A device in which nuclear fission may be sustained and controlled in a
self-supporting nuclear reaction. The varieties are many, but all incorporate
certain features, including fissionable material or fuel, a moderating material
(unless the reactor is operated on fast neutrons), a reflector to conserve
escaping neutrons, provisions of removal of heat, measuring and controlling
instruments, and protective devices. The reactor is the heart of nuclear
power plant.
Recycling
A process that separates used fuel into: uranium; waster (fission products);
and transuranics (a mixture of plutonium, americium, neptunium and curium)
for reuse in reactors. The transuranic elements are incorporated into fuel
for fast reactors and then destroyed while the reactor generates electricity.
Recycling would be done with UREX+ or pyroprocessing depending on the type of
fuel to be recycled. Contrast with "throw away" fuel cycle.
Spent Nuclear Fuel (used nuclear fuel)
Nuclear fuel that is used in a reactor for a number of years before losing
its ability to efficiently create energy. As a typical nuclear reactor
operates, the fission process creates energy to generate electricity.
During this process, the uranium is being used up and fission products
accumulate and interfere with efficiency until the fuel can no longer
effectively produce energy. At this point, the used fuel is said to be
"spent" and is replaced. If directly disposed, spent nuclear fuel can only
be disposed in a geologic repository where the waste is to be isolated
essentially permanently from the biosphere. Contrast with "low-level
waste".
Thermal Reactor (thermal pectrum reactor)
A nuclear power plant that can use only certain isotopes of uranium and the
transuranic elements. Neutrons producing fission are slowed down, or
moderate to relatively low energies before creating new fission reactions.
Contrast with "fast reactor".
Throw Away Fuel Cycle
A process in which nuclear fuel is used once in a nuclear power plant and
then thrown away; also called "open" or "once-through". Contrast with
"recycle" or "closed" fuel cycle.
Tonnes (metric ton)
1,000 kilograms; 2,200 pounds.
