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| Igeo value | Igeo class | Designation of sediment quality |
|---|---|---|
| >5 | 6 | Extremely contaminated |
| 5–4 | 5 | Strongly to extremely contaminated |
| 4–3 | 4 | Strongly contaminated |
| 3–2 | 3 | Moderately to strongly contaminated |
| 2–1 | 2 | Moderately contaminated |
| 1–0 | 1 | Uncontaminated to moderately contaminated |
| <0 | 0 | Uncontaminated |
