THE CHALLENGE:
The client, QinetiQ, was required to undertake remediation works to enable surrender of a lease of a redundant parcel of land and allow safe access to the public. The work was completed to address pollutant linkages identified by the project environmental consultants including shallow soil with asbestos fibres and erosion of made ground by the River Stour. Made Ground forming a raised riverbank was contaminated with metals, PAH’s and asbestos (bulk and fibrous). The initial engineering design was to implement a costly, low sustainability sheet-piled solution to retain the riverbank.
All works had to be undertaken in close consultation with the Environment Agency under a Flood Defence Consent. The Local Authority Ecologist was also consulted on all works due to the suspected presence of potential Otter Holts in the Riverbank.
OUR SOLUTION:
Soilfix completed the following works fully in accordance with the Control of Asbestos Regulations and CL:AIRE Code of Practice, including:
- Controlled excavation of asbestos impacted fill materials along 120m Riverbank and adjacent stockpiles, regrading bank profile back to original. Works carried out with rescue boat in attendance;
- Classification & disposal of segregated asbestos contaminated fill materials considered to present a long-term risk to future site occupants;
- Riverbank stabilisation using a sustainable , innovative ‘bio-engineered’ solution (significant saving on sheet pile with greater amenity value); and,
- Importation / placement of clean soils for restoration capping. Hydro-seeded with a wildflower meadow mix.
All works were completed on programme with zero lost-time accidents, resulting in a significant saving on the original ‘hard engineered’ bank stabilisation approach.
Stringent health, safety & environmental monitoring / controls were implemented, including personal & perimeter air tests, personnel decontamination, regular health screening and operation of a rescue boat.
