In this study, rainfall infiltration in vault of the second near-surface disposal facility was evaluated on the basis of various disposal scenarios. A total of four different disposal scenarios were examined based on the locations of the radioactive waste containers. A numerical model was developed using the FEFLOW software and finite element method to simulate the behavior of infiltrated water in each disposal scenario. The effects of the disposal scenarios on the infiltrated water were evaluated by estimating the flux of the infiltrated water at the vault interfaces. For 300 years, the flux of infiltrated water flowing into the vault was estimated to be 1 mm/year or less for all scenario. The overall results suggest that when the engineered barriers are intact, the flux of infiltrated water cannot generate a sufficient pressure head to penetrate the vault. In addition, it is confirmed that the disposal scenarios have insignificant effects on the infiltrated water flowing into the vault.

1. Introduction
2. Design of the Second Phase Near-surfaceDisposal Facility
3. Methodology
    3.1 Disposal Scenarios Considered in NumericalSimulation
    3.2 Governing Equation
    3.3 Concept Model of Numerical Simulation
    3.4 Boundary Conditions and Input Parameters
    3.5 Mesh
4. Results and Discussion
    4.1 Distribution of Saturation
    4.2 Pathways of Infiltrated Water
    4.3 Flux of Infiltrated Water
5. Conclusion
REFERENCES

• Mijin Kwon(Korea Radioactive Waste Agency)
• Hyungoo Kang(Korea Radioactive Waste Agency)
• Chunhyung Cho(Korea Radioactive Waste Agency) Corresponding Author