Table 13 Migration distance of pollutants in loess layer.
SO42− | F− | Ni | Cr | Cd | Pb | |
|---|---|---|---|---|---|---|
Maximum migration depth on Day 21 for rain (cm) | 56 | 56 | 55 | 55 | 55 | 55 |
Depth of concentration up to standard on Day 21 for rain (cm) | 0 | 0 | 23 | 5 | 9 | 28 |
National standard on drinking water quality (mg/l) | ≤ 250 | ≤ 1.0 | ≤ 0.05 | ≤ 0.05 | ≤ 0.01 | ≤ 0.05 |
