ASTM C1553-08

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: C1553 − 08
Standard Guide for
Drying Behavior of Spent Nuclear Fuel
This standard is issued under the fixed designation C1553; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Barrier Systems (EBS) for Geological Disposal of High-
Level Radioactive Waste
1.1 This guide is organized to discuss the three major
C1562 Guide for Evaluation of Materials Used in Extended
components of significance in the drying behavior of spent
Service of Interim Spent Nuclear Fuel Dry Storage Sys-
nuclear fuel: evaluating the need for drying, drying spent
tems
nuclear fuel, and confirmation of adequate dryness.
2.2 ANSI/ANS Standards:
1.1.1 The guide addresses drying methods and their limita-
ANSI/ANS 8.1-1998 Nuclear Criticality Safety in Opera-
tions in drying spent nuclear fuels that have been in storage at
tions with Fissionable Materials Outside Reactors
water pools. The guide discusses sources and forms of water
ANSI/ANS-8.7-1998 Nuclear Criticality Safety in the Stor-
that remain in SNF, its container, or both, after the drying
age of Fissile Materials
process and discusses the importance and potential effects they
ANSI/ANS-57.9 American National Standard Design Crite-
may have on fuel integrity, and container materials.The effects
ria for Independent Spent Fuel Storage Installation (Dry
of residual water are discussed mechanistically as a function of
Type)
the container thermal and radiological environment to provide
2.3 Government Documents:
guidance on situations that may require extraordinary drying
Title 10 on Energy, Code of Federal Regulations, Part 60, 10
methods, specialized handling, or other treatments.
CFR 60, U.S. Code of Federal Regulations, Disposal of
1.1.2 The basic issue in drying is to determine how dry the
High Level radioactive Wastes in Geologic Repositories
SNF must be in order to prevent issues with fuel retrievability,
Title 10 on Energy, Code of Federal Regulations, Part 63, 10
container pressurization, or container corrosion. Adequate
CFR 63, U.S. Code of Federal Regulations, Disposal of
dryness may be readily achieved for undamaged commercial
High-Level Radioactive Wastes in Geologic Repository at
fuel but may become a complex issue for any SNF where
Yucca Mountain, Nevada
cladding damage has occurred during fuel irradiation, storage,
Title 10 on Energy, Code of Federal Regulations, Part 71, 10
or both, at the spent fuel pools. Dryness issues may also result
CFR71, U.S.CodeofFederalRegulations,Packagingand
from the presence of sludge, crud, and other hydrated com-
Transport of Radioactive Materials
pounds connected to the SNF that hold water and resist drying
Title 10 on Energy, Code of Federal Regulations, Part 72, 10
efforts.
CFR 72, U.S. Code of Federal Regulations, Licensing
1.2 This standard does not purport to address all of the
Requirements for the Independent Storage of Spent
safety concerns, if any, associated with its use. It is the
Nuclear Fuel and High-Level Radioactive Waste
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
3. Terminology
bility of regulatory limitations prior to use.
3.1 Definitions—Terms used in this guide are as defined in
2. Referenced Documents Practice C1174 or, if not defined therein as per their common
usage, except where defined specifically for this guide as
2.1 ASTM Standards:
described as follows.
C1174 Practice for Prediction of the Long-Term Behavior of
3.2 Definitions of Terms Specific to This Standard:
Materials, Including Waste Forms, Used in Engineered
3.2.1 CRUD, n—in nuclear waste management, deposits on
fuel surfaces from corrosion products that circulate in the
This guide is under the jurisdiction ofASTM Committee C26 on Nuclear Fuel
reactor coolant. Compositions reflect materials exposed to
Cycle and is the direct responsibility of Subcommittee C26.13 on Spent Fuel and
High Level Waste.
Current edition approved Jan. 1, 2008. Published February 2008. DOI: 10.1520/
C1553-08. Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St.,
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C1553 − 08
coolant and activation products formed during irradiation. vapor, free or unbound liquid water, physisorbed water,
Term was originally an acronym for “Chalk River Unidentified chemisorbed water, and ice. The following specific terms for
Deposits.” water are used in this document:
3.2.12.1 bound water, n—bound water includes adsorbed
3.2.2 damaged fuel, n—in nuclear waste management,
surface layers of water, and nearly all chemisorbed water.
nuclear fuel that has been geometrically altered in form/shape
to a degree that may affect retrievability from a (licensed)
3.2.12.2 chemisorbed water, n—water that is bound to other
storage system or make it unsuitable for transport in a licensed
species by forces whose energy levels approximate those of a
cask.
chemical bond.
3.2.3 disposal, n—in nuclear waste management, the em-
3.2.12.3 physisorbedwater(adsorbedwater),n—waterthat
placement of radioactive wastes in a geologic repository with
is physically bound (as an adsorbate, by weak forces) to
the intent of leaving it there permanently. 10 CFR Part 63.2
internal or external surfaces of solid material.
3.2.4 failed fuel, n—in drying of spent nuclear fuel, any
3.2.12.4 trapped water, n—unbound water that is physically
breach, such as hairline cracks or holes in a cladding that
trapped or contained by surrounding matrix, blocked vent
permits water into a fuel element. pores, cavities, or by the nearby formations of solids that
prevent or slow escape. Note: Traps may have varying degrees
3.2.5 getter, n—in nuclear waste management, a material
of reversibility and a trap may be for practical purposes
(typically a solid) used to chemically react with certain gases
irreversible.
(for example, H ,O ,H O vapor) to form a solid compound of
2 2 2
3.2.12.5 unbound water, n—water, in the solid, liquid, or
low vapor pressure.
vapor state, that is not physically or chemically bound to
3.2.5.1 Discussion—A getter may also be used to absorb
another species.
impurities in chemical and metallurgical processes.
3.2.6 independent spent fuel storage installation (ISFSI),
4. Significance and Use
n—a complex designed and constructed for the interim storage
4.1 This guide provides technical information for use by
of spent nuclear fuel and other radioactive materials associated
SNFownerstodeterminetheformsofwaterusuallyassociated
with spent fuel storage. 10 CFR Part 72
with spent nuclear fuel due to corrosion damage of the fuel,
3.2.7 packaging, n—in nuclear waste management,anas-
claddingandstoragematerialsduringirradiationandinstorage
sembly of components used to ensure compliance with the
pools.DryingmaybeneededtopreparetheSNFforsealeddry
requirements of Title 10 of the Code of Federal Regulations,
storage, transportation, and/or permanent disposal at a reposi-
(CFR)Part72forindependentstorageofspentnuclearfueland
tory. This guide provides information for:
high-level radioactive waste or 10 CFR Part 71 for transpor-
4.1.1 Evaluating what drying system should be used,
tation of radioactive materials.
4.1.2 Drying methods, and
3.2.8 repository, geologic repository, n— in nuclear waste
4.1.3 Methods to confirm that adequate dryness was
management, a disposal site, a permanent location for radio-
achieved.
active wastes.
4.2 The guide can be used to determine:
3.2.9 spentnuclearfuel(SNF),n—nuclearfuelthathasbeen
4.2.1 Drying technologies that are designed to remove most
irradiated in a nuclear reactor and contains fission products,
of the unbound water but will not remove all forms of water.
activation products, actinides, and un-reacted fissionable fuel.
Water remaining on and in commercial and research reactor
Normally spent fuel is contained in a metal cladding whose
spent nuclear fuels coming from water basin storage may
condition (undamaged, corroded, perforated, etc.) depends
becomeanissuewhenthefuelissealedinadrystoragesystem
upon its original material properties as modified by the
or transport cask. The movement to a dry storage environment
conditions during its service life including storage conditions.
typically results in an increase in fuel temperature due to the
decay heat. This temperature change could be significant to
3.2.10 sludge, n—in nuclear waste management, a slurry or
cause the release of water remaining in a sealed dry package
sediment containing nuclear waste materials, a residue that has
that may result in container pressurization, fuel retrievability
usually been formed from processing operations, corrosion or
issues, and container corrosion.
water basin storage.
4.2.2 A methodology for evaluating drying processes that
3.2.11 wastepackage,n—innuclearwastemanagement,the
maynotreadilyremoveallformsofwaterthatmayberetained
waste form and any containers, shielding, packing and other
in pores in fuel cladding, capillaries, sludge, crud, and thin
absorbent materials immediately surrounding an individual
wetted surface films. Drying techniques are even less success-
waste container. 10 CFR Part 60
ful in removing bound water. Removal of bound water will
3.2.11.1 Discussion—The waste package is expected to
only occur when the specific threshold energy is applied to
consist of an overpack (a container) into which commercial
break the bonds involved and release the water. For spent
SNF, DOE SNF canisters and high level waste are to be placed
nuclear fuel this threshold energy may come from the combi-
for disposal at a repository.
nation of thermal input and ionizing radiation.
3.2.12 water, n—in drying of spent nuclear fuel,itisthe 4.2.3 How the residual water retained with the SNF, CRUD
total amount of moisture (specified by weight, volume, or and sludge inside a sealed package may become available to
number of moles) present (in a container) as a combination of react with the internal environment, the fuel, and the package
C1553 − 08
materialsasaresultofextendedtimeatequilibriumdrystorage For the purposes of SNF transport per 10 CFR 71.55, fuel is
temperatures, or as the direct result of radiolytic decomposi- essentially regarded as “failed” only when the geometric form
tion. of the fuel has been “substantially altered.” For the purposes of
dry cask storage per 10 CFR 72.22, the SNF cladding is
required to: “be protected against degradation and gross
5. Evaluating the Drying Approach
rupture.” Gross rupture is defined as that which could result in
5.1 Some forms of fuel degradation—such as cladding
the release of significant quantities of fuel materials and fission
pinholes or cracks—may form before or during the dry storage
products to the storage environment. For the purposes of
period without violating design or licensing requirements.
receipt of SNF containers at a geologic repository, 10 CFR 961
However, damage such as small cladding cracks or pinholes
defines three categories of commercial LWR “failed fuel:”
formed during the dry storage period could cause the fuel to be
Class F-1 failed fuel has visually observable failure or damage
re-classified as failed fuel for repository disposal consider-
Class F-2 failed fuel has “radioactive leakage”
ations.The objective in drying commercial LWR SNF contain-
Class F-3 failed fuel is badly damaged and requires “encapsulation”
ers is to eliminate enough water to preclude “gross” damage to
Each of these damaged or failed fuels could potentially
commercial fuel or its cladding during dry storage and trans-
require different handling/treatment than those used for non-
port. The drying process itself must not damage the fuel. For
failed fuel. It is, therefore, important when addressing the
example, the thermal cycling during the drying process for
potential for fuel damage or failure due to moisture in the SNF
commercial LWR SNF may affect the hydride re-orientation
containers to be clear about the kind and extent of cladding
process in the zircaloy cladding.
damage. It is particularly important to note that SNF could be
5.2 DOE research and production reactor SNF that is not
regarded as intact or non-failed for the purposes of storage or
treated or reprocessed, will eventually be stored in sealed
transportperformancebut“failed”forthepurposesofgeologic
canisters within dry storage systems that may or may not be
repository disposal. This potential exists because of the rela-
regulated by the NRC. DOE dry storage canisters are expected
tively predictable performance of damaged fuel for a dry
to contain the SNF through interim storage, transport, and
storagetermversustheverydifficultpredictionofperformance
repository packaging. The objectives of drying processes used
in geologic time. Commercial SNF may be characterized as
on this fuel are to:
intact or failed through the use of one or more of the following
5.2.1 Preclude geometric reconfiguration of the packaged
processes:operatingrecords(corehistoryandhandling),visual
fuel,
examinations, ultrasonic testing, wet or dry sipping, and eddy
5.2.2 Prevent internal damage to the canister from over-
current testing. Fuel type and the presence/type of defects
pressurization or corrosion, and
involved are essential starting points for analysis of drying. In
5.2.3 Minimize hydrogen generation or materials corrosion order to organize the information in this guide, the varieties of
that could be a problem during transport or repository handling spent fuels in existence have been placed into categories with
operations. a letter designation for consideration. Similarly, the types of
defects to be considered are identified with a number designa-
5.3 The decision to select the drying methodology for
tion. The identities of these categories are provided below.
treating fuel for interim dry storage facility or disposition in a
5.4.1 SNF Grouping—The following groupings for SNF are
geologic repository could be based on the following factors:
used in this guide to dis
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