A more thorough explanation:

Definition: Leaching is the process of separating the soluble components of a material by moving fluid. This term is often used to describe the migration of contaminating materials from a fixed source, such as a landfill, by rain or groundwater. Under CERCLA, leaching is considered a release of contaminants.

• When rainwater seeps through a landfill, it can leach out harmful chemicals and pollutants into the surrounding soil and groundwater.
• Leaching can also occur in agriculture when excess fertilizers are applied to crops. The excess nutrients can leach into the soil and contaminate nearby water sources.

These examples illustrate how leaching can cause contamination and environmental damage. It is important to properly manage and dispose of hazardous materials to prevent leaching and protect our natural resources.