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2025 Vol.35, Issue 3 Preview Page

Research Article

Optimized Investigation Methods for Discontinuities and a Stepwise Investigation Strategy for Deep Geological Disposal of High-Level Radioactive Waste

고준위 방사성폐기물 심층처분을 위한 최적화된 불연속면 조사 방법 및 단계별 조사 전략 제안

Junghae Choi12*
최 정해12*
1Professor, Department of Earth Science Education, Kyungpook National University
2Researcher, Science Education Research Institute, Kyungpook National University
1경북대학교 지구과학교육과 교수
2경북대학교 과학교육연구소 운영위원
*Corresponding Author
30 September 2025. pp. 367-379
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Abstract

Rock discontinuities influence groundwater flow and the mechanical stability of engineered structures in deep geological repositories for high-level radioactive waste. Here, I present a methodological framework and a stepwise investigation strategy to support the systematic characterization of discontinuities during site selection and evaluation. Rather than conducting a site-specific analysis, I propose a generalized approach based on the classification and quantification of key attributes of the discontinuities (including orientation, spacing, persistence, roughness, and aperture), following international standards such as the suggested methods of the International Society for Rock Mechanics and Rock Engineering (ISRM). The investigation techniques covered include surface outcrop surveys (manual and remote sensing), borehole imaging and hydrogeological tests, and subsurface investigations at underground research laboratories (URLs), focusing on the identification of excavation damaged zones (EDZs). The proposed strategy is structured into three investigation stages: regional-scale reconnaissance, site-scale characterization, and in-depth repository-scale assessment. Each stage has clearly defined objectives, methods, and data integration procedures. This study aims to provide a practical reference for improving the efficiency, consistency, and reliability of discontinuity investigations for the characterization of deep disposal sites, particularly in contexts where long-term geological safety is paramount.

Keywords
high-level radioactive waste
deep geological disposal
rock discontinuity
quantitative investigation
stepwise strategy

고준위 방사성폐기물의 심층처분에 있어 암반 내 불연속면은 지하수 유동 경로 및 처분 구조물의 안정성에 중요한 영향을 미치는 핵심 요소로 간주된다. 본 연구는 이러한 불연속면의 특성을 정량적으로 평가하고, 심층처분 부지 특성화에 효과적으로 적용하기 위한 최적화된 조사 방법과 단계별 조사 전략을 제안한다. 제안된 방법론은 불연속면의 주요 특성(방향, 간격, 연장성, 거칠기, 개방 폭 등)에 대한 체계적 정의와 함께, 국제암반공학회(International Society for Rock Mechanics and Rock Engineering, ISRM) 권고안에 기반한 정량화 항목을 정리하였으며, 조사 기법으로는 지표 노두 조사(직접 측정 및 디지털 원격 탐사), 시추공 기반 영상 분석 및 수리 시험, 지하 연구시설을 활용한 굴착 손상대(excavation damaged zone, EDZ) 특성화 등이 포함된다. 조사 전략은 지역 규모 예비조사, 부지 규모 상세 조사, 처분장 규모 심층조사(underground research laboratory, URL 기반)의 세 단계로 구분되며, 각 단계에서의 조사 목적, 기법, 데이터 연계 구조를 체계적으로 제안하였다. 본 연구는 장기 안전성 확보를 위한 암반 불연속면 조사에 있어 기술적·운영적 효율성을 높일 수 있는 실용적인 지침을 제공하는 데 그 목적이 있다.

키워드
고준위 방사성폐기물
심층처분
암반 불연속면
정량화 조사
단계별 전략
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Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 35
  • No :3
  • Pages :367-379
  • Received Date : 2025-09-02
  • Revised Date : 2025-09-15
  • Accepted Date : 2025-09-15
  • DOI :https://doi.org/10.9720/kseg.2025.3.367
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