• Assessment of Metal Diffusion Due to Stabilization of Vadose Zone Soil Through Groundwater Monitoring using Diffusive Gradients in Thin Films

  • Kyu-Young Shim1, Kwangjin Park2, Seungwoo Lee2, Jongmin choi2, Daeho Kim2, Jinsung An1,3*, and Kyoungphile Nam4

  • 1Department of Smart City Engineering, Hanyang University, Ansan 15588, South Korea
    2Daeil Engineering & Construction CO., LTD., Seoul 06719, South Korea
    3Department of Civil and Environmental Engineering, Hanyang University, Ansan 15588, South Korea
    4Department of Civil and Environmental Engineering, Seoul National University, Seoul 08826, South Korea

  • Diffusive gradients in thin films 기반 지하수 모니터링을 통한 불포화대 토양 안정화에 따른 중금속 확산 여부 평가

  • 심규영1ㆍ박광진2ㆍ이승우2ㆍ최종민2ㆍ김대호2ㆍ안진성1,3*ㆍ남경필4

  • 1한양대학교 ERICA 스마트시티공학과
    2(주)대일이앤씨
    3한양대학교 ERICA 건설환경공학과
    4서울대학교 건설환경공학부

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This study evaluated groundwater metal behavior before and after stabilization in a difficult-to-remediate site using diffusive gradients in thin films (DGT). Iron salt solutions (FeCl3) and neutralizing agents (NaOH) were sequentially injected into the vadose zone for in situ Fe oxides synthesis, and time-weighted average concentrations (TWAC) of As, Cd, and Zn in the groundwater at four monitoring wells were determined using the DGT to assess the changing patterns of metal leaching from the vadose zone into groundwater. To determine whether the average concentration changed after stabilization, a Welch’s t-test was applied. The results showed that no statistically significant changes were observed for all metals in all wells, with p-values exceeding 0.05. Also, a segmented regression was applied to detect the change points and slope shifts. Most change points occurred before stabilizing agent injection, and those observed after injection showed no significant slope changes. Overall, stabilizing agent injection had no significant effect on groundwater metals, while the DGT-segmented regression approach was useful for detecting gradual dispersion.


Keywords: Passive sampling, Diffusive boundary layer, Segmented regression, Groundwater contamination, Difficult-to-remediate site

This Article

  • 2025; 30(5): 22-29

    Published on Oct 31, 2025

  • 10.7857/JSGE.2025.30.5.022
  • Received on Aug 13, 2025
  • Revised on Aug 22, 2025
  • Accepted on Aug 27, 2025

Correspondence to

  • Jinsung An

  • 1Department of Smart City Engineering, Hanyang University, Ansan 15588, South Korea
    3Department of Civil and Environmental Engineering, Hanyang University, Ansan 15588, South Korea

  • E-mail: jsan86@hanyang.ac.kr