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2025 Vol.35, Issue 3 Preview Page

Technical Note

Numerical Assessment of Leachate Reduction in the Boeun Landfill, Wanju

완주군 보은매립장의 침출수 저감을 위한 수치해석적 평가

Juhyeun Lee1
,
Min-Ho Koo2*
이 주현1
,
구 민호2*
1Engineer, Geotech & Tunnel Dept., Yooshin
2Professor, Department of Geoenvironmental Sciences, Kongju National University
1㈜유신 지반터널부 사원
2공주대학교 지질환경과학과 교수
*Corresponding Author
30 September 2025. pp. 461-473
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Abstract

Leachate generated by the illegal landfill of solidified sludge has been leaking from the Boeun Landfill in Wanju, causing foul odors and contamination of surrounding water resources. To address this, a groundwater flow model was developed using Visual MODFLOW, and both steady-state and transient simulations were performed to evaluate leachate discharge. The model was calibrated with observed groundwater levels and leachate data, using hydraulic conductivity and recharge as key parameters. Four scenarios were established to assess leachate reduction: installation of a geomembrane, a vertical cutoff wall, and two pumping operations. Results showed that a geomembrane reduced groundwater inflow, the cutoff wall blocked leachate discharge through the retaining wall and valley, and adequate pumping completely eliminated external leachate outflow. Transient simulations under normal and wet year conditions revealed that geomembrane installation delayed groundwater rise, and even with 1.6 times higher precipitation, leachate discharge increased by only about 14%. This study demonstrates the effectiveness of combining cutoff facilities with pumping for leachate reduction in landfills lacking protective systems. The modeling approach provides a quantitative basis for designing treatment systems and can be applied to other legacy or illegal landfills in support of remediation and ecological restoration.

Keywords
Boeun Landfill
leachate
groundwater flow model
pumping and treatment

완주군 보은매립장은 고화토의 불법 매립으로 인해 침출수가 외부로 유출되면서 악취와 인근 지표수·지하수 오염을 유발하고 있다. 이에 본 연구에서는 Visual MODFLOW를 이용하여 지하수 흐름 모델을 개발하고, 정류 및 부정류 모의를 통해 침출수 거동을 정량적으로 평가하였다. 모델 보정은 관측정 지하수위와 침출수 처리량 자료를 활용하였으며, 주요 보정 변수는 수리전도도와 함양량으로 설정하였다. 침출수 저감을 평가하기 위해 차수막 설치, 차수벽 추가 설치, 불충분한 양수 운영, 적정 양수 운영의 네 가지 시나리오를 설정하였다. 시나리오별 모의 결과, 차수막은 매립지 내부로의 지하수 유입을 효과적으로 줄였고, 차수벽은 옹벽과 골짜기를 통한 침출수 유출을 차단하였다. 양수를 병행할 경우 매립지 외부로의 침출수 유출이 완전히 제거되는 것으로 나타났다. 부정류 모의에서는 평년해와 다우해 조건을 고려하였으며, 차수막 설치로 강우 증가에 따른 지하수위 상승이 지연되었다. 특히 강수량이 평년 대비 1.6배 증가한 다우해에서도 침출수 처리량 증가는 약 14% 수준에 불과하였다. 본 연구는 매립지에서 차수시설과 양수 운영을 병행하는 방법이 침출수 저감에 효과적임을 보여주었다. 또한 본 연구에서 제시한 수치모의 접근법은 침출수 처리공법 설계의 기초자료로 활용될 수 있으며, 향후 불법 매립지나 노후 매립지의 복원 및 관리에도 적용 가능하다.

키워드
보은매립장
침출수
지하수흐름모델
양수처리
References
1

BAI (Board of Audit and Inspection of Korea), 2020, Audit report: Management and supervision of waste landfill in Wanju (in Korean).

2

Cho, W., Kang, D., Koo, T., 2000, Leachate Transport at the Nanji Waste Landfill, Institute of Technology and Science, 30, 13-21 (in Korean).

3

Hong, M., Kim, Y., 1969, Geological Map of Samrye (1:50,000), Geological Survey of Korea (in Korean).

4

Jeollabuk-do, 2010, Report of Jeollabuk-do Groundwater Management Plan (in Korean).

5

Jung, G., Lee, J., 2007, A study on the characteristics of landfill gas and leachate in NANJIDO after constructed final cover system, Journal of Korea Society of Waste Management, 24(8), 744-751 (in Korean with English abstract).

6

Kang, D., Cho, W., Lee, J., 2001, The behavior of leachate on the transient condition in the Nanji waste landfill, Journal of Soil and Groundwater Environment, 6(2), 57-67 (in Korean with English abstract).

7

Kim, G., Koo, J., Won, H., Oh, W., 2000, A study on methods reducing groundwater contamination around Kimpo landfill, Journal of the Korean Society of Groundwater Environment, 7(1), 1-7 (in Korean with English abstract).

8

Koh, Y., 2018, The study on cutting-off the leachate leakage or infiltration from waste landfill by wall mass constructed in underground, Journal of the Korean Geoenvironmental Society, 19(10), 27-34 (in Korean with English abstract).

10.14481/JKGES.2018.19.10.27
9

Koo, T., Cho, W., 2001, Estimation of the groundwater movement under the heavy rainfall at Nanji waste landfill, Journal of Soil and Groundwater Environment, 6(3), 107-117 (in Korean with English abstract).

10

Lee, D., Nam, K., and Ji, J., 1980, Geological map of Ganggyeong (1:50,000), Korea Institute of Energy and Resources (in Korean).

11

ME (Ministry of Environment), 2020, White paper of environment 2020 (in Korean).

12

MOCT (Ministry of Construction and Transportation), 2000, Report of basic plan for river maintenance of Yonghakcheon (in Korean).

13

MOLIT (Ministry of Land, Infrastructure and Transport), 2017, Modification plan of Basic plan for groundwater management (2017~2026) (in Korean).

14

Shin, K., Park, Y., Bae, W., 2004, Reduction of leachate generation from landfills under operation by installing geomembrane, In: Proceedings of the 2004 Autumn Conference of the Korea Society of Waste Management, 2004(1), Incheon, 434-437 (in Korean).

15

Visang, 2020, Report of basic and implemented design services for ecological restoration project of the Boeun Landfill in Wanju (in Korean).

16

Wanju-gun, 2019, Report of service for analysis and management of contaminated water in the Boeun Landfill, Wanju (in Korean).

Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 35
  • No :3
  • Pages :461-473
  • Received Date : 2025-08-25
  • Revised Date : 2025-09-16
  • Accepted Date : 2025-09-25
  • DOI :https://doi.org/10.9720/kseg.2025.3.461
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