Landfill Temporary Cap
Journey partnered with the Client to engineer a cost-effective temporary cap system for a Class II landfill. The goal of the cap design was to reduce leachate production, improve waste stability, and reduce operational expenses. Work included engineering, design, procurement, construction management, and field QA/QC inspection services. The project involved waste grading, waste stability monitoring and mitigation, design and installation of various geosynthetic Lineral Low-Density Polyethylene (LLDPE) liners and geocomposites, and a water management system including culverts and drainage ditches.
One of the unique challenges with completing a large area landfill cap is managing the future surface run-off water from the newly capped area. Recognizing the challenge that the Client would face with this large volume of water, Journey developed a Surface Water Management Plan and system to allow Operations to effectively manage the large volume of water during snow melt and rainfall events. The system included specialized culvert systems (HDPE and CSP), a network of strategically placed ditches and diversion berms, as well as erosion control measures such as rip-rap, erosion control matting, and check-dams.
Another challenge of the project was staging the capping work to mitigate the risk of a leachate overflow and waste instability. Journey worked with the Client and Contractor to phase the waste grading work to minimize stability concerns and to control leachate by directing the leachate to strategically located sumps/bellholes. This allowed Operations to have continual access to accumulation areas and remove leachate throughout the duration of construction.
