ASTM C1174-17

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: C1174 − 07 (Reapproved 2013) C1174 − 17
Standard Practice for
PredictionEvaluation of the Long-Term Behavior of
Materials, Including Waste Forms, Materials Used in
Engineered Barrier Systems (EBS) for Geological Disposal
1
of High-Level Radioactive Waste
This standard is issued under the fixed designation C1174; 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
1.1 This practice describes addresses how various test methods and data analyses can be used to develop models for the
predictionevaluation of the long-term alteration behavior of materials, such asmaterials used in engineered barrier system (EBS)
materials and waste forms, used in the geologic for the disposal of spent nuclear fuel (SNF) and other high-level nuclear waste
in a geologic repository. The alteration behavior of waste formforms and EBS materials is important because it affects the retention
of radionuclides by the disposal system. The waste form and EBS materials provide a barrier to release either directly (aswithin
the disposal system either directly, as in the case of waste forms in which the radionuclides are initially immobilized),immobilized,
or indirectly (asindirectly, as in the case of EBS containment materials that restrict the ingress of groundwater or the egress of
radionuclides that are released as the waste forms and EBS materials degrade).degrade.
1.1.1 Steps involved in making such predictions include problem definition, testing, modeling, and model confirmation.
1.1.2 The predictions are based on models derived from theoretical considerations, expert judgment, interpretation of data
obtained from tests, and appropriate analogs.
1.1.3 For the purpose of this practice, tests are categorized according to the information they provide and how it is used for
model development and use. These tests may include but are not limited to the following:
1.1.3.1 Attribute tests to measure intrinsic materials properties,
1.1.3.2 Characterization tests to measure the effects of material and environmental variables on behavior,
1.1.3.3 Accelerated tests to accelerate alteration and determine important mechanisms and processes that can affect the
performance of waste form and EBS materials,
1.1.3.4 Service condition tests to confirm the appropriateness of the model and variables for anticipated disposal conditions,
1.1.3.5 Confirmation tests to verify the predictive capacity of the model, and
1.1.3.6 Tests or analyses performed with analog materials to identify important mechanisms, verify the appropriateness of an
accelerated test method, and to confirm long-term model predictions.
1.2 The purpose of this practice is to provide a scientifically-based strategy for developing models that can be used to estimate
material alteration behavior after a repository is permanently closed (that is, the post-closure period) because the timescales
involved with geological disposal preclude direct validation of predictions.
1.3 The purpose of this practice is to provide methods for developing models that can be used for the prediction of materials
behavior over the long periods of time pertinent to the service life of a geologic repository as part of the basis for performance
assessment of the repository. This practice also addresses uncertainties in materials behavior models and the impact on the
confidence in the EBS design criteria, the scientific bases of alteration models, and repository performance assessments using those
models. This includes the identification and use of conservative assumptions to address uncertainty in the long-term performance
of materials.
1.3.1 Steps involved in evaluating the performance of waste forms and EBS materials include problem definition, laboratory and
field testing, modeling of individual and coupled processes, and model confirmation.
1.3.2 The estimates of waste form and EBS material performance are based on models derived from theoretical considerations,
expert judgments, and interpretations of data obtained from tests and analyses of appropriate analogs.
1
This practice is under the jurisdiction of ASTM Committee C26 on Nuclear Fuel Cycle and is the direct responsibility of Subcommittee C26.13 on Spent Fuel and High
Level Waste.
Current edition approved April 1, 2013July 1, 2017. Published April 2013August 2017. Origi
...