Conceptual Framework:
Former landfill sealed in 1988, with a rainwater collection system and chimneys installed for biogas extraction. Currently, the site hosts a football field with its respective facilities. In the early years after sealing, minor ground collapses and unpleasant odors from organic decomposition were reported. As a corrective measure, a passive gas extraction system and a monitoring and control plan for underground water and gas were implemented.
Problem Statement:
- Biogas (methane) emissions at the football field facilities
- High concentrations of biogas
- Ground subsidence
- Exposure risk for field users
Control and Monitoring Methodology:
1. Air:
- Passive gas extraction system through landfill chimneys
- Periodic emission control at various monitoring points, sewer system, and wells: CH₄, CO₂, O₂, CO, H₂S, VOCs
- Annual subsurface gas sampling
- Periodic active gas extraction
2. Water:
- Monitoring of leachate levels at control points
- Evaluation of the drainage network condition
- Leachate quality sampling
- Topographic leveling to monitor ground settlement
Results Obtained:
- Seasonal fluctuation of gas emissions
- Improved understanding of the subsurface environment
- Reduction in biogas concentrations due to active extraction
- Stabilization of gas emissions through the passive chimney system
- Ground stabilization and topographic control
