Numerical Study of Contaminant Pathway based on Generic-scenarios and Contaminant-based Scenarios of Vadose Zone

Chang, Sun Woo, Kim, Min-Gyu, Chung, Il-Moon

doi:10.12652/Ksce.2019.39.6.0751

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2019 Vol.39, Issue 6 Preview Page Next Page

Water Engineering

Numerical Study of Contaminant Pathway based on Generic-scenarios and Contaminant-based Scenarios of Vadose Zone 범용 시나리오 및 오염물질 시나리오에 기반한 불포화대 오염물질 경로에 대한 수치모의 연구

December 2019. pp. 751-758

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Abstract

본 연구는 오염부지의 위해성 평가를 위해 수치모의 기반 오염물질의 노출이동경로 평가에 활용가능한 개념모델을 제시하였다. 이를 위하여 1차원으로 유한차분 기법을 적용하여 지하수 내 오염물질 이송확산을 모의하였다. 불포화대 경로에서의 수리지질학적 및 오염물질 매개변수가 가질 수 있는 범위를 설정하여 범용 시나리오 및 오염물질별 시나리오를 구성하여 모의에 적용하였다. 모델에서는 흡착 및 생분해를 갖는 유한 차분 1 차원 이송확산이 고려되었고, 또한 초기 농도가 시간이 지남에 따라 고갈되는 것을 가정하였다. 일반 시나리오의 결과는 지하수 침투율이 감소함에 따라, 오염원에서 지하수면까지의 경로가 길어질수록 지하수면으로 유입되는 지점의 농도 범위는 낮아졌다. 특히, 높은 생분해 속도와 오염원의 빠른 고갈의 경우, 범용 시나리오가 좁은 범위의 지하수 유입농도 예측치를 보여주었다.

키워드

오염부지 위해성평가

노출농도

수치모델

불포화대

지하수

토양오염물질

오염부지

This study tested various assumptions that simplified the configuration of the numerical model for unsaturated zone’s contaminant transport to simulate the pathway to exposed point. This study investigated the contaminant migration through in the pollutant exposure pathway of vadoze zone for risk assessment of the contaminated site. For the purpose, generic scenarios as well as contaminant-based scenarios were simulated using the numerical code for transport of the contaminant in the pathway. The finite-difference one-dimensional transport with adsorption and biodegradation were considered, and it also assumed that the initial concentration was also depleted over time. The results of the generic-scenario show that as the groundwater infiltration rate decreases, the longer the path from the source to the groundwater level, the lower the concentration at the point of inflow into the groundwater level. In particular, in the case of high biodegradation rate and rapid depletion of pollutant sources, statistically outliers were found in the simulated results and generic scenarios was good at prediction.

Keywords

Risk assessment

Exposed concentration

Numerical model

Unsaturated zone

Groundwater

Contaminant

Contaminated site

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Information

Publisher :Korean Society of Civil Engineers
Publisher(Ko) :대한토목학회
Journal Title :KSCE JOURNAL OF CIVIL AND ENVIRONMENTAL ENGINEERING RESEARCH
Journal Title(Ko) :대한토목학회 논문집
Volume : 39
No :6
Pages :751-758
Received Date :2019. 11. 05
Revised Date :2019. 11. 12
Accepted Date : 2019. 02. 01
DOI :https://doi.org/10.12652/Ksce.2019.39.6.0751

KSCE JOURNAL OF CIVIL AND ENVIRONMENTAL ENGINEERING RESEARCH ISSN:1015-6348(Print) 2287-934X(Online) 대한토목학회 논문집

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