Environmental Engineering Reference
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the repository in another, and disposed of in yet another. The cask used for each
function must meet a specific set of criteria. For example, the transportation cask
must be capable of withstanding several types of accidents while the disposal
cask must be highly corrosion resistant. Different types of materials are used
to meet those requirements, and it would be prohibitively expensive to build
a cask that met the requirements for all three uses. In addition, U.S. nuclear
power plants have many different designs, and those plants use fuel assemblies
with different dimensions. Rather than design and build several different casks to
store, transport, and dispose of these different shapes and sizes of fuel assemblies,
OCRWM plans to build a canister whose internal structure can be varied to
accommodate a variety of assembly designs but whose external dimensions allow
it to be put into a standard cask. The TAD also makes it easier to transfer the
used fuel assemblies from storage cask, to transportation cask, to disposal cask
with minimum effort and risk. Five-year contracts for the design, licensing, and
demonstration of the TAD canister system were awarded to two corporations in
May 2008 (USDOE 2008b).
5
REGULATIONS GOVERNING TRANSPORTATION OF USED
NUCLEAR FUEL AND HLW
The U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of
Transportation (DOT) regulate the transportation of used nuclear fuel and HLW.
The NRC's regulations, found in 10 CFR Part 71, specify the requirements for
packaging for these highly radioactive materials, including procedures for approv-
ing the packaging. Packages used for transporting used nuclear fuel and HLW
are referred to as Type B packages. Type A packages are used for radioactive
materials emitting much less radiation than used nuclear fuel or HLW. Type B
packages are heavy casks designed to shield people and the environment from
radiation emitted by the used fuel or HLW and to contain the radioactive material
under both normal and accident conditions.
Any packages used for transporting used nuclear fuel must have a Radioactive
Material Package Certificate of Compliance from the U.S. Nuclear Regulatory
Commission. To obtain a Certificate of Compliance, the cask manufacturer must
first submit an application providing information specified in NUREG-1617,
“Standard Review Plan for Transportation Packages for Spent Nuclear Fuel”
(USNRC 2000). The application must address the safety and operational char-
acteristics of the package, including design analysis for structural and thermal
characteristics, radiation shielding, nuclear criticality, material content confine-
ment, and the four accident test conditions listed. In addition, the application
must contain operational guidance, such as any testing and maintenance require-
ments, operating procedures, and conditions for package use (USNRC 2007b).
Any cask for transporting used nuclear fuel must contain the radioactive material
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