Which soil is most suitable for cover material at a landfill site?

The most suitable soil for cover material at a landfill site is one that is easily worked and minimizes infiltration. This type of soil is important because it helps to control leachate production and minimizes the movement of water through the waste layers. Efficient cover material prevents rainwater from infiltrating the landfill, which can lead to the creation of leachate—a liquid that can carry contaminants away from the waste. By using soil that is easily worked, landfill operators can effectively lay down the cover material to ensure proper compaction and stability.

Soils that minimize infiltration help maintain optimal moisture levels within the landfill, which is crucial for the decomposition processes. In landfill management, maintaining a balance between moisture and soil properties is vital to minimize environmental impacts and facilitate safe, effective operations over time. Having cover materials that restrict infiltration supports the preservation of the surrounding groundwater and soil quality.

The other options may not effectively address the critical requirement for controlling infiltration or may not be practical from an operational standpoint, highlighting the importance of choosing the right type of soil for landfill cover applications.