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2026 Vol.36, Issue 3 Preview Page

Research Article

Reconciling Regulatory Thresholds and Pollution Index Values in Coastal Dredged Sediments: Distinguishing the Geogenic Baseline from Contamination via Multi-Criteria Cross-Validation

남해 연안 준설토의 다중기준 교차판정: 진동층 자연배경 보정을 통한 ‘기준초과≠오염’의 판별

Sunhee Choi12
,
Minjune Yang34*
,
Kangjoo Kim2*
최 선희12
,
양 민준34*
,
김 강주2*
1Deputy Director, Goseong-Tongyeong-Geoje Branch, Korea Rural Community Corporation
2Professor, Department of Environmental Engineering, Kunsan National University
3Professor, Major of Environmental Geosciences, Division of Earth Environmental System Sciences, Pukyong National University
4President, Wible Co., Ltd.
1한국농어촌공사 고성통영거제지사 차장
2군산대학교 환경공학과 정교수
3국립부경대학교 지구환경시스템과학부 환경지질과학전공 정교수
4㈜와이블 대표이사
*Corresponding Author
30 September 2026. pp. 423-436
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Abstract

Coastal agricultural reservoirs created by seawall construction on reclaimed tidal flats are a distinctive environment in which marine-derived sediment undergoes prolonged brackish-to-freshwater transformation, requiring contamination assessment approaches distinct from those employed for inland reservoirs. This study evaluated the heavy-metal contamination of dredged sediment from the Madong Reservoir (Goseong, Korea), where the underlying black shale of the Cretaceous Jindong Formation is a potential geogenic source of As, Cr, and Ni. A total of 86 sediment samples (38 surface samples and 48 subsurface samples from 12 core stations) were analyzed for eight heavy metals (As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg). The results were cross-validated against three frameworks: the Korean soil contamination concern standards (SCCS), the beneficial use of dredged material criteria (BUDM), and the U.S. NOAA sediment quality guidelines (SQGs). All metals were within the SCCS and BUDM limits at each station. In contrast, As, Cu, and Ni exceeded the NOAA threshold effect level (TEL) at 100%, 92%, and 98% of stations, respectively, although none exceeded the probable effect level (PEL). Geochemical indices resolved this discrepancy: the geoaccumulation index (Igeo) identified only Cd as enriched (mean 1.09), whereas As, Cr, and Ni were near or below the regional background; the mean PEL quotient (0.23–0.35) and mean PEC quotient (0.22–0.29) indicated uniformly low ecological risk (< 0.5) at all stations. The potential ecological risk index was dominated by Cd and Hg (77% of the total), and principal component analysis separated an anthropogenic Cu–Ni–Zn factor from a geogenic As–Cd factor. Element ratios (i.e., a Ni/Cr ratio 1.03 times the background value) and vertical profiles (Cd enriched at depth, with As, Cr, and Ni being vertically uniform) were consistent with an origin from the black shale of the Jindong Formation. The results demonstrate that the apparent TEL exceedance of As, Cu, and Ni is a geogenic false positive result rather than representing anthropogenic contamination. The results also support the terrestrial reuse of the dredged material and highlight the need for region-specific geochemical background values when evaluating the contamination of dredged sediment from geologically distinctive areas.

Keywords
dredged sediment
multi-criteria cross-validation
geoaccumulation index
Jindong Formation
geogenic background
ecological risk assessment

연안지역에 방조제를 축조하여 조성한 농업용 담수호는 해양 기원 퇴적물이 장기간 담수화 과정을 거치는 독특한 환경으로, 내륙 저수지와는 구별되는 퇴적물 평가 접근이 요구된다. 이 연구에서는 기반암인 중생대 백악기 진동층 흑색 셰일이 As·Cr·Ni의 잠재적 자연 공급원인 경남 고성군 마동호 준설토를 대상으로 중금속 오염도를 평가하였다. 표층 38개와 12개 정점의 주상 48개 등 총 86개 시료의 8개 중금속(As, Cd, Cr, Cu, Ni, Pb, Zn, Hg)을 토양오염우려기준(SCCS), 활용 가능한 준설물질 기준(BUDM), 미국 NOAA 퇴적물 질 기준(SQGs)의 세 기준계에 교차 적용하였다. 모든 중금속은 전 정점에서 SCCS와 BUDM 기준 이내였으나, NOAA TEL에 대해서는 As·Cu·Ni가 각각 100%, 92%, 98%의 정점에서 초과하였고 PEL을 초과한 항목은 없었다. 이러한 불일치는 지구화학적 지수로 규명되었다. 농집지수(Igeo)에서 Cd만 농집(평균 1.09)되었고 As·Cr·Ni는 지역 배경농도 수준 또는 그 이하였으며, 평균 PEL 지수(0.23–0.35)와 평균 PEC 지수(0.22–0.29)는 전 정점에서 낮은(< 0.5) 생태위해도를 나타내었다. 잠재생태위해지수는 Cd과 Hg가 전체의 77%를 차지하였고, 주성분 분석은 인위기원 Cu·Ni·Zn 인자와 자연기원 As·Cd 인자를 분리하였다. 원소비(배경비의 1.03배인 Ni/Cr)와 Cd의 심부 농집 및 As·Cr·Ni의 수직 균질성 또한 진동층 흑색 셰일 기원과 부합하였다. 이 결과는 As·Cu·Ni의 TEL 초과가 인위적 오염이 아니라 자연기원에 의한 위양성임을 보여주며, 준설토의 육상 매립 및 재활용 타당성을 지지하고, 지질학적으로 특수한 지역의 준설토 평가 시 지역 배경농도의 도입이 필요함을 시사한다.

키워드
준설토
다중기준 교차판정
농집지수
진동층
자연배경농도
생태위해성 평가
References
1

Abrahim, G.M.S., Parker, R.J., 2008, Assessment of heavy metal enrichment factors and the degree of contamination in marine sediments from Tamaki Estuary, Auckland, New Zealand, Environmental Monitoring and Assessment, 136(1-3), 227-238.

10.1007/s10661-007-9678-2
2

Facchinelli, A., Sacchi, E., Mallen, L., 2001, Multivariate statistical and GIS-based approach to identify heavy metal sources in soils, Environmental Pollution, 114(3), 313-324.

10.1016/S0269-7491(00)00243-8
3

Hakanson, L., 1980, An ecological risk index for aquatic pollution control: A sedimentological approach, Water Research, 14(8), 975-1001.

10.1016/0043-1354(80)90143-8
4

Jin, D.R., Lee, M., Yang, H.J., Kim, S., Lee, J.S., Moon, S.D., 2022, Evaluation of metal contamination in brackish area sediments South Korea, using receiver operation characteristic curve, Marine Pollution Bulletin, 184, 114175.

10.1016/j.marpolbul.2022.114175
5

Kang, J.H., Lee, S.J., Jeong, W.G., Cho, S.M., 2012, Geochemical characteristics and heavy metal pollutions in the surface sediments of oyster farms in Goseong Bay, Korea, The Korean Journal of Malacology, 28(3), 233-244 (in Korean with English abstract).

10.9710/kjm.2012.28.3.233
6

Lee, G., Hwang, D.W., Hwang, H., Park, J.H., Kim, H.C., Kwon, J.N., 2017, Distribution and pollution status of organic matter and heavy metals in surface sediment around Goseong Bay, a shellfish farming area, Korea, Journal of the Korean Society of Marine Environment & Safety, 23(6), 699-709 (in Korean with English abstract).

10.7837/kosomes.2017.23.6.699
7

Lee, J.S., Chon, H.T., Kim, J.S., Kim, K.W., Moon, H.S., 1998, Enrichment of potentially toxic elements in areas underlain by black shales and slates in Korea, Environmental Geochemistry and Health, 20(3), 135-147.

10.1023/A:1006571223295
8

Long, E.R., Field, L.J., MacDonald, D.D., 1998, Predicting toxicity in marine sediments with numerical sediment quality guidelines, Environmental Toxicology and Chemistry, 17(4), 714-727.

10.1002/etc.5620170428
9

MacDonald, D.D., Carr, R.S., Calder, F.D., Long, E.R., Ingersoll, C.G., 1996, Development and evaluation of sediment quality guidelines for Florida coastal waters, Ecotoxicology, 5(4), 253-278.

10.1007/BF00118995
10

MacDonald, D.D., Ingersoll, C.G., Berger, T.A., 2000, Development and evaluation of consensus-based sediment quality guidelines for freshwater ecosystems, Archives of Environmental Contamination and Toxicology, 39(1), 20-31.

10.1007/s002440010075
11

MOF (Ministry of Oceans and Fisheries), 2018, Marine environmental standards, MOF Notification No. 2018-10 (in Korean).

12

MOF (Ministry of Oceans and Fisheries), 2021, Regulation on the utilization of dredged material, MOF Notification No. 2021-137 (in Korean).

13

Müller, G., 1969, Index of geoaccumulation in sediments of the Rhine River, GeoJournal, 2(3), 108-118.

14

Reimann, C., Filzmoser, P., Garrett, R.G., 2002, Factor analysis applied to regional geochemical data: Problems and possibilities, Applied Geochemistry, 17(3), 185-206.

10.1016/S0883-2927(01)00066-X
15

Seo, M., Kim, J., Lee, J., Choi, Y.J., Ryu, J.S., 2023, Assessment of heavy metal contamination and ecological risk in riverine sediments collected at the Hyeongsan River Basin, South Korea, Journal of the Geological Society of Korea, 59(3), 463-472 (in Korean with English abstract).

10.14770/jgsk.2023.038
16

Smith, S.L., MacDonald, D.D., Keenleyside, K.A., Ingersoll, C.G., Field, L.J., 1996, A preliminary evaluation of sediment quality assessment values for freshwater ecosystems, Journal of Great Lakes Research, 22(3), 624-638.

10.1016/S0380-1330(96)70985-1
17

Tomlinson, D.L., Wilson, J.G., Harris, C.R., Jeffrey, D.W., 1980, Problems in the assessment of heavy-metal levels in estuaries and the formation of a pollution index, Helgoländer Meeresuntersuchungen, 33(1-4), 566-575.

10.1007/BF02414780
18

Tuttle, M.L.W., Breit, G.N., Goldhaber, M.B., 2009, Weathering of the New Albany Shale, Kentucky: II. Redistribution of minor and trace elements, Applied Geochemistry, 24(8), 1565-1578.

10.1016/j.apgeochem.2009.04.034
19

Woo, J., Lee, H., Park, J., Park, K., Cho, D., Jang, D., Park, S., Choi, M., Yoo, J., 2019, Background concentration and contamination assessment of heavy metals in Korean coastal sediments, The Sea: Journal of the Korean Society of Oceanography, 24(1), 64-78 (in Korean with English abstract).

10.7850/jkso.2019.24.1.064
20

Yi, J.M., Chon, H.T., Park, M., 2003, Migration and enrichment of arsenic in the rock-soil-crop plant system in areas covered with black shale, Korea, The Scientific World Journal, 3, 194-198.

10.1100/tsw.2003.1912806106PMC5974760
Information
  • Publisher :Korean Society of Engineering Geology
  • Publisher(Ko) :대한지질공학회
  • Journal Title :The Journal of Engineering Geology
  • Journal Title(Ko) :지질공학
  • Volume : 36
  • No :3
  • Pages :423-436
  • Received Date : 2026-08-19
  • Revised Date : 2026-09-04
  • Accepted Date : 2026-09-07
  • DOI :https://doi.org/10.9720/kseg.2026.3.423
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