Class | Value | Levels of contamination |
0 | Igeo < 0 | Uncontaminated |
1 | 0 < Igeo < 1 | Uncontaminated to moderately contaminated |
2 | 1 < Igeo < 2 | From contaminated to moderately contaminated |
3 | 2 < Igeo < 3 | From moderately contaminated to severely contaminated |
4 | 3 < Igeo < 4 | Severely contaminated |
5 | 4 < Igeo < 5 | From severely contaminated to extremely contaminated |
6 | 5 < Igeo | Extremely contaminated |