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The Igeo and classification of pollution degree.
| Igeo Class | Igeo Value | Pollution Degree |
|---|---|---|
| 0 | Igeo ≤ 0 | Uncontaminated |
| 1 | 0 < Igeo ≤ 1 | Slightly to moderately contaminated |
| 2 | 1 < Igeo ≤ 2 | Moderately contaminated |
| 3 | 2 < Igeo ≤ 3 | Moderately to heavily contaminated |
| 4 | 3 < Igeo ≤ 4 | Heavily contaminated |
| 5 | 4 < Igeo ≤ 5 | Heavily to extremely contaminated |
| 6 | Igeo > 5 | Extremely contaminated |
