An historic leaking active effluent drain on the site resulted in a sub-surface plume of radiological contamination. Also running through the area was a network of land drains that essentially acted as a pathway for mobilising Caesium137 contamination to the foreshore. Cognition designed a containment system comprising a barrier wall keyed into the natural clay beneath the site and capped with stabilised site-won material to reduce permeability and prevent surface water ingress into the contaminated plume area.
Cognition was contracted by Magnox to remediate the contaminated area between the Hunterston ‘A’ and ‘B’ stations, known as the Catch-pit 7 (CP7) compound. Due to the radioactive nature of the site, the level of precision required during excavation and remediation was crucial. The key elements of these works included:
The slurry wall and cap was installed successfully and fully compliant with the Client’s tight design specification and delivering a highly sustainable and robust solution. The project demonstrated Cognition’s ability to meet very high standards expected within the nuclear industry. Cognition has since been awarded three further remediation projects for the nuclear industry in the UK.