SCOPE

• Bulk excavation of the upper 500–800mm of loose material along the designated trench alignment
• Excavation to required design subgrade level using GPS-controlled plant
• Sidecasting of all excavated material in accordance with site constraints
• Coordination with the Principal Contractor to confirm founding conditions, including subgrade replacement where required
• Design, supply, and installation of shoring boxes fitted with 900mm struts to maintain a safe working environment during pipe installation
• Installation of geofabric internally within shoring boxes, with external placement adopted where constrained by strut locations
• Placement and screeding of 75mm 20mm aggregate layer to design level to form a stable trench base
• Installation of leachate pipes to line and level, including electrofusion welding of all couplings to manufacturer specifications
• Installation of trench stops at nominated locations as required by design
• Backfilling of trench with 40mm aggregate to existing surface levels

EXECUTION

The works delivered a complete leachate trench installation, inclusive of bulk and subgrade excavation using GPS-controlled plant, shoring box installation with 900mm struts, geofabric lining, aggregate bedding, and accurate pipe installation with electrofusion-welded couplings. Subgrade conditions were closely monitored in coordination with the Principal Contractor, with replacement carried out where required. Trench stops were installed at all nominated locations, and the trench was backfilled with 40mm aggregate to existing surface levels to ensure the structural integrity and long-term performance of the leachate system. All safety and environmental controls were implemented and maintained throughout, demonstrating Everest Civil's capability to safely manage confined excavations and quality assurance requirements while working closely with a Tier 1 contractor.