Development of a Coordinate-Based 3D Visualization Tool for Integrated Subsurface Characterization of High-Level Radioactive Waste Repositories

The safety assessment of a Deep Geologic Repository (DGR) for high-level radioactive waste in Korea necessitates a precise and integrated understanding of subsurface conditions. Building upon previous research that established a basic 3D site model for intuitive geological understanding, this study focuses on developing an integrated 3D visualization tool. The primary objective is to develop the procedures to manage and visualize diverse investigation datasets by integrating them into a coordinate-based 3D framework, thereby enhancing the reliability of site characterization.

The input data for the proposed tool are categorized into geological features and investigation results. Geological features, including volumes and surfaces (e.g., faults), are constructed by interpolating point clouds from surface maps and joining boundaries within the SKUA-GOCAD environment. Investigation data, comprising geotechnical and geophysical results, are structured into a 4x3 matrix based on their spatial forms (point, line, surface, volume) and physical quantities (scalar, vector, tensor). This systematic classification allows the tool to accommodate all standard investigation formats within a unified spatial environment.

The developed visualization tool provides three core capabilities: 1) Spatial Precision: A coordinate-based system ensures the exact locations of multi-source investigation data. 2) Intuitive Visualization of Physical Quantities: The position and magnitude of physical quantities of scalars, vectors, and tensors can be verified intuitively. The tool utilizes RGB color mapping (blue for low values, red for high values) to represent the magnitude of physical quantities, making data interpretation straightforward. 3) Spatial Interaction and Feedback: The tool enables the analysis of geological attributes along borehole trajectories and geophysical cross-sections. This spatial comparison facilitates a feedback loop, allowing the 3D model to be iteratively refined and updated based on empirical investigation data.

Currently, the tool’s functionality has been verified using geological and investigation data from the research testbed. This integrated approach significantly improves the efficiency of site characterization and provides a robust foundation for DGR safety assessments. Future research will focus on program stabilization, thorough verification and the implementation of advanced analytical features to support long-term site monitoring and management.