Description: This report is a case study of a field trial for the ex-situ remediation of coal tar sludges from disposal lagoons at Grassmoor, Derbyshire, prior to the redevelopment of this contaminated site. The report describes the nature of the contamination found at the site and also the potential hazards resulting from the contamination. The unusual nature of the type and scale of contamination necessitated the need to assess a number of remediation techniques. The proposed technique of bioremediation meant that the usual procurement methods would not meet the trial’s objectives of minimising the financial and technical risks to both the client and treatment contractor. The report therefore includes sections on the selection procedures used for appointing the field trials contractor and also the contractual framework used. Additional laboratory testing and monitoring enabled independent verification of the treatment process and an assessment to be made of residual contamination likely to remain at the end of the treatment programme. Further sections of the report draw on the outcomes of the field trials to offer a financial assessment of the treatment process and present conclusions drawn from the field trials and the remediation methods used.

Keywords: pollution prevention, urban regeneration, ground improvement, contaminated land