What is the minimum amount of soil cover required after landfill closure?

The correct answer of two feet of soil cover after landfill closure is based on regulatory standards and best practices for ensuring environmental protection and stability of the landfill site. This amount of soil cover serves several critical functions.

Firstly, it helps to prevent water infiltration into the landfill, which can lead to leachate formation—a potentially harmful liquid that can contaminate surrounding soil and groundwater. By providing adequate soil cover, experts aim to minimize the contact between precipitation and the waste material buried below.

Secondly, a two-foot layer of soil supports vegetation growth, which is essential for stabilizing the landfill surface. Vegetation can help to reduce erosion caused by wind and water, creating a natural barrier that protects the landfill’s integrity over time.

Finally, this soil cover acts as a protective layer against pests and wildlife, reducing the likelihood of animals disturbing the landfill materials. The thickness of two feet has been established as a practical balance between effective environmental protection, landscaping needs, and construction considerations at landfill sites.