Decontaminating industrial sites
Ecologia was contracted for remediation work on an industrial site with a history of use as a gas works and production centre of precast concrete where the underlying soils and groundwater were contaminated with asbestos, petroleum hydrocarbons, metals and volatile organic compounds. Several former underground gas work structures also remaine, including gas holder and tar tank.
Ecologia were involved in the very early stages of the project, assisting in assessing the extent of contamination and advising on the most effective remediation strategy. Extensive light non-aqueous phase liquid (LNAPL) contamination was initially encountered on part of the site and the client decided to undertake in-situ voluntary Multi Phase Extraction (MPE) remediation in advance of planning permission being granted. This proved very successful with over 4,000 litres of LNAPL being removed during this stage of the remediation works.
The remediation works commenced in conjunction with the early stages of demolition works. Ecologia applied an integrated approach comprising bulk excavation, hot spot removal, complex sorting and screening, ex-situ soil biotreatment using engineered biopiles, off-site disposal of unsuitable materials, and water treatment. Targeted hot spot removal and treatment of contaminated soils allowed for the maximum re-use of suitable site won soils achieving a significant cost saving in waste disposal and import costs.A robust validation and verification scheme underpinned the remediation works and ensured that regulatory sign off could be achieved swiftly. Material movements on site were tracked under a Material Management Plan (MMP) which also incorporated the transfer of naturally occurring soil onto site which was required to make up for material shortages following off-site disposal of unsuitable soils.
Ecologia successfully completed the work over 14 months. Utilising a collaborative approach with the client proved to be very successful as the potential environmental liabilities associated with the development were fully understood thus minimising costs. This approach also provided the necessary confidence and guarantees so that the client could successfully divest the site whilst the works were still ongoing.