I 'Concrete barriers will be used as intimate parts of systems for isolation of low-level radioactive wastes subsequent to l disposal. This work reviews mathematical models for estimating the degradation rate of concrete in typical service environments. The models considered cover sulfateattack, reinforcement corrosion, calcium hydroxide leaching, carbonation, l freeze/thaw, and cracking. Additionally, fluid flow, mass ! transport, and geochemical properties of concrete are briefly reviewed. Example calculations included illustrate the types of predictions expected of the models.

This report summarizes the results of a study to improve the estimates of the radionuclides in the low-level radioactive waste (LLW) inventory which is buried in the Idaho National Engineering Laboratory (INEL) Radioactive Waste Management Complex (RWMC) Subsurface Disposal Area (SDA). The work is done to support the RWMC draft performance assessment (PA). Improved radionuclide inventory estimates are provided for the INEL LLW generators. Engineering, environmental assessment or other research areas may find use for the information in this report, lt may also serve as a LLW inventory baseline for data quality assurance. The individual INEL LLW generators, tfieir history and their activities are also described in detail.

This report documents user instructions for several simplified subroutines and driver programs that can be used to estimate various aspects of the long-term performance of cement-based barriers used in low-level radioactive waste disposal facilities. The subroutines are prepared in a modular fashion to allow flexibility for a variety of applications.Three levels of codes are provided: the individual subroutines, interactive drivers for each of the subroutines, and an interactive main driver, CEMENT, that calls each of the individualdrivers.The individual subroutines for the different models may be taken independently and used in larger programs, or the driver modules can be used to execute the subroutines separately or as part of the main driver routine. A brief program description is included and user-interface instructions for the individual subroutines are documented in the main report. These are intended to be used when the subroutines are used as subroutines in a larger computer code. User instructions for the drivers and example interactive screens for the main drivers are provided in Appendix A. Examples showing the use of the individual driver routines to execute the different subroutines and test data are included in Appendix B. Programmer notes are provided in Appendix C and the configuration control system is discussed in Appendix D.