Secondary containment is the process of planning for eventual leaks, spills, and other forms of exposure. Even the best leachate ponds and collection systems can eventually fail if there’s a bad enough storm or emergency. Designing the basins and walkways around the leachate ponds with secondary containment in mind can add extra protection and help control where the wastewater goes if there is an overflow.
- Line all transfer areas for sump pumps and pathways under pipes that run over the surface. Spills and leaks from these parts of the system can lead to widespread leachate exposure.
- Plan the leachate ponds to contain enough rainwater to reach the 100-year flood records for the area. This ensures that a sudden rainfall event won’t overwhelm the system.
- Reinforce the overflow areas for the pond and line them to ensure erosion doesn’t wear away the ground cover in case of a serious release of wastewater. Overflow areas can collapse and allow wastewater to destabilize the rest of the landfill if they’re not protected from sudden erosion effects.