Leaching occurs when rainfall dissolves chemicals and carries them into groundwater. Which statement best describes this process?

Leaching occurs when rainfall dissolves chemicals and carries them into groundwater. Which statement best describes this process?

• A. Surface runoff cleans soil
• B. Leaching is when rainfall dissolves chemicals and carries them into groundwater
• C. Evaporation purifies water
• D. Condensation concentrates pollutants

Answer: (B)

Leaching is about the downward movement of dissolved substances through soil as water from rainfall percolates downward, carrying solutes into groundwater. When rain infiltrates, it dissolves chemicals such as nutrients or pollutants and moves with the infiltrating water through the soil profile until it reaches the water table. The process depends on how easily water can move through the soil (permeability), how soluble the chemicals are, and how much water is passing through. This differs from surface runoff, which drains water across the surface and can remove contaminants without transporting them into groundwater. Evaporation removes water to the atmosphere and can leave behind dissolved solids, but it doesn’t transport pollutants downward into groundwater. Condensation involves water vapor turning back into liquid and doesn’t describe the downward movement of dissolved substances into groundwater in the same way.

Leaching is about the downward movement of dissolved substances through soil as water from rainfall percolates downward, carrying solutes into groundwater. When rain infiltrates, it dissolves chemicals such as nutrients or pollutants and moves with the infiltrating water through the soil profile until it reaches the water table. The process depends on how easily water can move through the soil (permeability), how soluble the chemicals are, and how much water is passing through.

This differs from surface runoff, which drains water across the surface and can remove contaminants without transporting them into groundwater. Evaporation removes water to the atmosphere and can leave behind dissolved solids, but it doesn’t transport pollutants downward into groundwater. Condensation involves water vapor turning back into liquid and doesn’t describe the downward movement of dissolved substances into groundwater in the same way.