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2026 Vol.31, Issue 1
A Review of PFAS Transport Mechanisms and Numerical Modeling in Unsaturated and Saturated Zones

불포화대 및 포화대 내PFAS 수송 기작 및 수치 모델링 연구 동향 리뷰

Taehoon Kim1*
,
Seunghak Lee1
,
Jaeshik Chung1
,
Sanghyun Kim1
김태훈 1*
,
이승학 1
,
정재식 1
,
김상현 1
1Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul, Republic of Korea
1한국과학기술연구원 물자원순환연구단
*Corresponding Author
28 February 2026. pp. 1-17
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Abstract

This paper reviews international research trends on per- and polyfluoroalkyl substances (PFAS) transport mechanisms and numerical modeling in subsurface environments. PFAS transport is governed by complex retardation mechanisms including non-equilibrium sorption, air-water interface (AWI) adsorption, and competitive sorption, with dynamic behavior associated with varying moisture conditions particularly in the vadose zone. Numerical models for simulating these processes have evolved from simple equilibrium-sorption-based approaches to multi-process rate-limited mass-transfer (MPMT) models. Representatively, HYDRUS effectively captures complex transport phenomena in the vadose zone by coupling a proven numerical platform with a PFAS-specific AWI module, MPMT-based models provide the most sophisticated interpretation of diverse retardation mechanisms through continuous model updates, and MODFLOW-based models are well-suited for comprehensive groundwater flow system analysis at site and watershed scales. Analysis of scale-dependent modeling studies reveals that the dominant factors controlling PFAS transport vary distinctly with scale: mass transfer limitations within thin water films at the pore scale, non-equilibrium sorption-desorption kinetics and competitive adsorption at the laboratory scale, and partition coefficients and hydrogeological characteristics at the field scale. Domestic PFAS research has focused primarily on treatment technologies, toxicity assessment, and contamination surveys, leaving subsurface transport modeling research at an early stage. Future research efforts should address the development of transport parameter databases suitable for domestic soil conditions, site-scale modeling studies reflecting source-specific characteristics, and methodologies for upscaling laboratory-scale parameters to field scales. This paper aims to contribute to the advancement of domestic research through a systematic review of PFAS transport mechanisms and numerical modeling.

Keywords
PFAS Transport
Numerical modeling
Retardation Mechanism
Air-water Interface Adsorption
Subsurface Environment
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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 :1
  • Pages :1-17
  • Received Date : 2025-12-18
  • Revised Date : 2026-01-19
  • Accepted Date : 2026-02-09
  • DOI :https://doi.org/10.7857/JSGE.2026.31.1.01
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