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2026 Vol.36, Issue 2

Technical Note

A Review of In-Situ Tracer Test in Fractured Rock

균열암반 현장 추적자 시험 수행사례 분석

Hangbok Lee1
,
Jung-Wook Park1
,
Byung-Gon Chae1
,
Chan Park1*
이 항복1
,
박 정욱1
,
채 병곤1
,
박 찬1*
1Principal Researcher, Deep Geological Disposal and Energy Storage Research Center, Korea Institute of Geoscience and Mineral Resources
1한국지질자원연구원 방폐물심층처분연구센터 책임연구원
*Corresponding Author
30 April 2026. pp. 103-129
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Abstract

Ongoing interest in deep geological repositories for high-level radioactive waste has led to the widespread implementation of in-situ tracer tests across various underground research facilities worldwide, targeting spatial scales ranging from centimeters to hundreds of meters. These tests have played a crucial role in identifying key parameters that influence the transport and retardation of radioactive nuclides in fractured rocks. Serving as essential empirical data, in-situ tracer tests contribute to the quantitative understanding of solute transport mechanisms in rock media and support the long-term safety assessment of disposal systems. The primary observable output of these tests is the concentration breakthrough curve, which provides insights into the transport and retention behavior of radionuclides. However, isolating and distinguishing the characteristic time-scales of transport and retardation solely from breakthrough curves remains a significant challenge due to the inherent complexity and uncertainty of numerical inversion. In particular, there remains an ongoing debate regarding the practical validity of in-situ tracer tests for evaluating large-scale and long-term radionuclide migration in fractured rock environments, and the methodological frameworks required for their interpretation. In this study, we present a comprehensive review of in-situ tracer test design and implementation cases, primarily conducted in domestic and international underground research laboratories, in the context of developing deep geological disposal concepts for high-level radioactive waste. Key information from in-situ tracer tests conducted in different countries was systematically reviewed, including site characteristics, test objectives, borehole configurations, types and injection amounts of tracers, and injection and pumping rates. This review aimed to identify the critical factors governing the design, execution, and interpretation of field tracer tests. The results are expected to contribute to improving the understanding and technical preparedness required for planning and conducting tracer tests during the detailed site investigation stage of future repository site selection in Korea.

Keywords
Radioactive waste
Nuclides
Fractured rock
In-situ tracer test
Concentration breakthrough curve

지하 방사성폐기물 처분장에 대한 지속적인 관심에 따라 방사성 핵종의 균열암반 내 이동 및 지연 특성에 영향을 미치는 주요 매개변수를 규명하기 위한 현장 추적자 시험이 전 세계 다양한 지하연구시설에서 센티미터에서 수백 미터 규모에 이르는 공간 규모를 대상으로 광범위하게 수행되어 왔다. 이러한 시험은 암반 매질 내에서의 용질 이동 메커니즘을 정량적으로 이해하고, 처분시스템의 장기적 안전성을 평가하는 데 필수적인 실증자료를 제공해 왔다. 현장 추적자 시험에서 획득되는 주요 관측 자료는 농도이력곡선이며, 이를 통해 핵종의 이동 및 지연 특성에 대한 정보를 추출할 수 있다. 그러나 농도이력곡선만으로 이동 및 지연에 대한 특성시간을 독립적이고 명확하게 구분하는 것은 수치적 역산의 불확실성과 복잡성으로 인해 여전히 도전적인 과제로 남아 있다. 특히, 균열암반 환경에서 방사성 핵종의 대규모 및 장기 이동 특성을 평가함에 있어, 현장 추적자 시험이 실제로 얼마나 유효하며, 어떤 해석 방법론과 연계되어야 하는지에 대해서는 여전히 다양한 논의가 진행 중이다. 본 보고에서는 고준위방사성폐기물 처분 개념의 개발을 목적으로 수행된 국내외 지하연구시설을 중심으로 현장 추적자 시험의 설계 및 수행 사례를 종합적으로 고찰하였다. 그 과정에서 각 국가에서 수행된 현장 추적자 시험을 대상으로 부지의 지질·수리지질학적 조건, 시험 목적, 시추공 배치 및 제원, 사용된 추적자 종류와 주입량, 주입·양수 유량 등 시험의 핵심 요소를 종합적으로 검토하였다. 이러한 비교·분석은 현장 추적자 시험의 설계와 해석에 영향을 미치는 주요 인자를 체계적으로 이해하는 데 목적이 있다. 본 검토 결과는 향후 국내 처분 부지 선정 과정의 상세조사 단계에서 요구되는 추적자 시험의 준비, 수행 및 해석 역량을 제고하는 데 기초 자료로 활용될 것으로 기대된다.

키워드
방사성폐기물
핵종
균열암반
현장 추적자 시험
농도이력곡선
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Information
  • Publisher :Korean Society for Rock Mechanics and Rock Engineering
  • Publisher(Ko) :한국암반공학회
  • Journal Title :Tunnel and Underground Space
  • Journal Title(Ko) :터널과 지하공간
  • Volume : 36
  • No :2
  • Pages :103-129
  • Received Date : 2026-04-03
  • Revised Date : 2026-04-20
  • Accepted Date : 2026-04-20
  • DOI :https://doi.org/10.7474/TUS.2026.36.2.103
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