Removal of a former industrial landfill site, construction of clay cut off wall, cement stabilisation and backfill.

Project: Removal of a former industrial landfill site, construction of clay cut off wall, cement stabilisation and backfill. Contaminant: Landfilled materials Challenges: Speed was critical in this project as timescales were tight due to the construction schedule. Additionally, artesian water conditions meant leachate/water control, treatment and disposal required careful management. Churngold Solution: A remediation strategy was devised with a view to removing the potential environmental risks relating to the former use of the site as an industrial landfill, thus satisfying the planning application. The landfilled waste was excavated to pre-agreed levels and stockpiled in a designated stockpile area. This was located within the waste, hence allowing any leachate to drain back into the waste without contaminating the surrounding area. In order to hydraulically isolate the site, a water impermeable barrier was constructed from imported clay, which was stabilised with a lime-cement mixture to meet the geotechnical requirements. A leachate lagoon was then built from site-won clay in order to store water pumped from within the excavation. The validation report confirmed the audit trail of soil and water movements off site allowing sign-off by the Regulatory Authorities. Churngold also assisted the Client in obtaining Corporation Tax Relief for the works. Technologies Employed: Construction of a clay cut off wall Ground Stabilisation by lime/cement Groundwater pump and treat

A clay wall was constructed in order to prevent ingress of water     Excavation of waste     The construction of a leachate lagoon removed the need for expensive hiring of leachate storage tanks