This field site is an unconfined alluvial aquifer consisting of coarse sands and gravels and other Quaternary glacial deposits interbedded with Tertiary sediments, over sandstone bedrock. The groundwater flow regime is complicated by the heterogeneous sedimentary architecture, industrial infrastructure and influenced by the surface morphology. The aquifer is contaminated with ammonium, MTBE, BTEX and other aromatic hydrocarbons derived from petroleum refining over many decades. The site is classified as a contaminated "megasite", based on the large scale and complexity of soil and groundwater pollution. Remediation infrastructure includes a cut-off wall to contain plume migration, supported by a pump and treat system with water-stripping. Previous research has focused on the potential for natural attenuation and demonstration of in situ remediation technologies for MTBE. Current activities include the development and pilot-scale evaluation of low-intensity biological and sorption-based remediation technology concepts, such as constructed experimental wetlands. The site is included within a wider programme of remediation technology demonstration for large-scale industrially-contaminated land.