0 When a chemical substance leaches or is leached from a material, especially soil, it is removed by the action of water passing through the material: --
1 (of a substance) to come out of or be removed from another substance, esp. dirt, by passing water through it --
The iron oxide presumably gets leached out from the surface of the cultivated land.
In either case the toxic or radioactive waste is trapped in the solid, preventing it from leaching into the local water table.
From this time onwards, leaching and erosion of soil was severe, causing major alluviation of valleys.
The farmer must try to prevent nitrates leaching through the soil, to limit the economic and environmental costs that this would generate.
Heavily leached soils also have a tendency to be easily eroded as the water washes away soil particles quickly.
The nitrates can be washed, or leached, out of the soil by rain into groundwater.
Data were summarized as mean cumulative cation losses from leaching columns of each treatment after each leaching event.
The soil was then leached with 95 % ethanol to remove free salts, air-dried and passed through a 2-mm sieve.
