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2026 Vol.31, Issue 2

Review

Hydrogeochemical Site Descriptive Modeling Development Methodology for Deep Geological Disposal of High-Level Radioactive Waste: A Review of the Swedish Forsmark Case

고준위 방사성폐기물 심층처분을 위한 수리지구화학 부지기술모델 설정 및 개발 방법론: 스웨덴 Forsmark 사례를 중심으로

Ho-Rim Kim1*
,
Heewon Jung2
,
SeHyeok Park1
,
Hanna Choi1
,
Hanna Kim3
,
Junseop Oh4
,
Jeong-Hwan Lee5
,
Seong-Taek Yun4
김 호림1*
,
정 희원2
,
박 세혁1
,
최 한나1
,
김 한나3
,
오 준섭4
,
이 정환5
,
윤 성택4
1Korea Institute of Geoscience and Mineral Resources, Daejeon 34132, Republic of Korea
2Chungnam National University, Daejeon 34134, Republic of Korea
3Suwon University, Hwaseong 18323, Republic of Korea
4Korea University, Seoul 02841, Republic of Korea
5Korea Radioactive Waste Agency, Republic of Korea
1한국지질자원연구원
2충남대학교
3수원대학교
4고려대학교
5한국원자력환경공단
*Corresponding Author
30 April 2026. pp. 1-15
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Abstract

A hydrogeochemical site descriptive model (SDM) is essential for evaluating the long-term safety of deep geological repositories for high-level radioactive waste (HLW). This review analyzes the hydrogeochemical SDM methodology developed by the Swedish Nuclear Fuel and Waste Management Company (SKB) for the Forsmark repository site. The SDM framework integrates quantitative field-based models with process-oriented conceptual models, evolving iteratively from feasibility study through initial and complete site investigation stages. The hydrogeochemical workflow comprises data acquisition and quality management, explorative analysis identifying groundwater types and end-member compositions (Deep Saline, Glacial, Littorina Sea, and Altered Meteoric Waters), quantitative modeling through M3 mixing calculations and PHREEQC geochemical simulations, and interdisciplinary integration with hydrogeological and transport models. The Forsmark SDM successfully characterized the stratified groundwater system, confirmed the long-term stability of reducing and pH-buffering conditions at repository depth, and quantified the role of paleohydrogeological events in shaping present-day hydrochemistry. Based on these findings, methodological considerations for developing a hydrogeochemical SDM in Korea are suggested, including updated thermodynamic database, open-source reactive transport codes, site-specific end-member definition, and global sensitivity analysis for uncertainty quantification.

Keywords
Site descriptive model (SDM)
Hydrogeochemistry
Deep geological disposal
Forsmark
Groundwater mixing
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Information
  • Publisher :The Korean Society of Soil and Groundwater Environment
  • Publisher(Ko) :한국지하수토양환경학회
  • Journal Title :Journal of Soil and Groundwater Environment
  • Journal Title(Ko) :지하수토양환경
  • Volume : 31
  • No :2
  • Pages :1-15
  • Received Date : 2026-02-15
  • Revised Date : 2026-03-01
  • Accepted Date : 2026-03-17
  • DOI :https://doi.org/10.7857/JSGE.2026.31.2.01
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