What are the closure and post-closure requirements for landfills?

The correct answer highlights the critical aspect of landfill management concerning leachate, which is the liquid that has percolated through waste material and contains various contaminants. After a landfill has closed, it is mandatory to continue the operation of the leachate collection and removal system until there is no further detection of leachate. This requirement is essential to protect groundwater and surface water resources from potential contamination.

Continued operation of the leachate management system ensures that any leachate generated after closure is effectively collected and treated, mitigating environmental hazards. The presence of leachate can significantly affect the quality of nearby water sources, so monitoring and managing it is a crucial part of post-closure care.

Other considerations, such as preventing stormwater run-on and run-off or maintaining leak detection systems, are indeed important aspects of landfill management but do not specifically address the post-closure responsibilities directly related to leachate. Though surveyed benchmarks may be significant for long-term monitoring and maintenance, they do not serve the immediate needs post-closure regarding leachate management. Thus, the focus on leachate collection and removal is essential in ensuring environmental protection in the context of landfill closure and post-closure requirements.