Ogden Landfill Remediation
Client:
City of Calgary
Location:
Calgary, Alberta
Year:
2018
Project Scope
Whissell served as Prime Contractor for the Ogden Landfill Remediation project at 24th Street and 91st Avenue SE, a complex environmental remediation and civil construction project that also included embankment construction for the future Green Line LRT right-of-way. The project required the safe removal and disposal of hundreds of thousands of tonnes of legacy waste material while constructing a permanent clay cap and associated storm infrastructure.
- Excavation and removal of 432,000 tonnes of waste material to City of Calgary landfills
- Stripping and stockpiling of 25,500 m³ of topsoil
- Construction of 110,000 m³ of embankment fill for the future Green Line LRT alignment
- Construction of a capping system including subsoil and topsoil layer placement (15,680 m²)
- 90,350 m² of hydroseeding and 3,735 m² of erosion control blanket installation
- Storm sewer installation and leachate management throughout the work area
- Implementation of a 24/7 Fire Mitigation Plan for spontaneous combustion risk management
Challenge & Mitigation
The most significant and unforeseen challenge was the spontaneous combustion of waste material during excavation. The dry waste composition, presence of methane gas, and introduction of oxygen created conditions where excavator bucket contact could ignite the material. After multiple combustion events, Whissell implemented a 24/7 temperature monitoring program using thermal sensors to identify high-heat zones prior to excavation. Highly toxic leachate from the landfill also required specialized handling protocols during clay cap and LRT embankment construction.
Value Add Solution
Whissell's proactive development of the Fire Mitigation Plan including continuous thermal monitoring and modified excavation sequencing in high-risk zones allowed the project to continue safely without extended shutdowns. The team's experience managing contaminated leachate from previous landfill projects enabled rapid implementation of appropriate handling and disposal protocols, avoiding regulatory delays.
