Site History This former coke works at Lambton contained a significant quantity of spent oxide material. As part of the reclamation strategy for the site this cyanide impacted material was to be remediated, to risk based criteria, utilising stabilisation/solidification processes.
Trial Design
VertaseFLI designed and engineered a treatment solution to chemically stabilise the contaminants. All works were undertaken in line with EA guidance and as such an initial laboratory study was carried out to demonstrate that the material could be successfully stabilised. This second phase of the works, again in line with EA protocols, was to demonstrate that the design derived from the previous laboratory based trial could be successfully replicated on a larger scale and still reduce contaminant leachate levels to below the risk based criteria. A range of standard engineering plant was utilised including soil rotovator, specialist mixing buckets, grout pumps and paddle mixer.
Trial Works
The works undertaken during the pilot trial demonstrated a number of key factors including; - Providing confidence that the selected methodology and mix design can achieve the remediation objectives.
- Demonstrating the consistency and repeatability of the stabilisation mix design on a site scale application.
- Allows any scaling factors due to site application to be identified and evaluated.
- Demonstrates the repeatability and consistency of the chosen treatment methodology.
Typically spent oxide material would require disposal off site as hazardous waste. However VertaseFLI successfully designed a chemical stabilisation solution and demonstrated that it could be applied effectively and efficiently at a site level. Furthermore to provide additional information for the full scale treatment all works were carried out in accordance with our own mobile treatment license and were fully integrated into the wider site activities. The full scale treatment of the waste, amounting to circa 20,000 m3, is scheduled to commence in spring 2008. | 
