How Do Liners Prevent Groundwater Contamination?
Imagine you are a raindrop that landed atop a landfill. After landing on a piece of waste, you trickle down through more waste, picking up contaminants along the way. Leachate is the term used to describe water that has passed through waste at a landfill. Unless a liner stops it, leachate can seep down through the soil until it joins and contaminates the local groundwater. Liners stop leachate before it can seep into the earth. Leachate collection pipes gather this contaminated water and send it to a central location. Leachate can be treated onsite or delivered to a wastewater treatment plant for treatment. North Carolina uses composite liners, which mean more than one material is used. First, a layer of soil is placed where the landfill will hold waste. Clay or some other earth that does not allow water to pass through easily is used for this layer. Next, a high density plastic liner is placed on top of the soil layer. A highly permeable layer of soil (that allows water to pass throug
