Statutory remediation for the new millennium - experience from Greenwich

A brief history of soil and water contamination on Greenwich peninsula, East London, (the National Millennium Exhibition site) is given. The remedial design process for the site is discussed. The process included the use of historical plans and surveys, detailed site investigation data, GIS contaminant mapping techniques, groundwater modelling and the construction of a site specific semi- quantitative risk assessment. The primary source contaminants found were coal tars and polyaromatic hydrocarbons, benzene, phenols and ammonia, while the secondary contaminants found were free cyanide, lead, arsenic and minerals. The design process identified pathways which linked contaminant sources with receptors and drew up a series of matrix tables for each source, pathway and receptor. The approximate qualitative level of risk was then assessed. The ongoing pollution of the Thames gravel aquifer was assessed as significant and a further quantitative assessment of the risks was incorporated into the remedial design. Details of the remedial design and treatment technologies employed are given together with the site supervision and regulatory involvement that was required. The lessons learnt and the future use of innovative technologies are discussed.