Remediation of former tannery site by E-Clay stabilisation.
Site Background & History.
The site was previously occupied by a tannery, the tannery was believed to be operational from the 1830’s to the 1960’s. The site was being redeveloped for residential use by
Arsenic concentrations on site typically ranged from 4,000 – 8,300 mg/kg with the highest concentration being 46,100 mg/kg.
Three remediation options were considered:
- A cover system (capping layer) to address human health concerns and to isolate the surface layers from the underlying contaminated soils / groundwater
- Excavation and removal from site
- On-site treatment by E-Clay Stabilisation
Envirotreat carried out treatability trials to determine the optimum stabilisation medium for treating the identified pollutants.
The proposed strategy involved the ex-situ remediation of 6,500 m3 of contaminated materials.
The contaminated materials were excavated and stockpiled prior to E-Clay treatment.
Following treatment, soils were stockpiled. Validation samples were submitted for total and leachable contaminant analysis. Analysis was compared to the agreed remediation target criteria.
A comprehensive Validation Report was prepared on completion of the remediation works.