Oxford Station Redevelopment
Project Scope and Delivery
The SYSTRA Geo-Environmental Team are working on the Oxford Station Redevelopment Scheme for Network Rail. As part of the outline design for the scheme, a ground investigation identified a potential contamination risk within one of the development areas. This potential contamination risk was raised the Network Rail design team and SYSTRA were commissioned to development and management strategy on behalf of Network Rail. Through working closely with Network Rail and the design team, SYSTRA were able to complete contaminated land risk assessments to understand the level of risk and identify a remediation strategy to address the risks that aligned with the local constraints.
SYSTRA designed a delineation survey to define the contamination area and assess the relevant pollutant linkages. Through the delineation survey, SYSTRA were able to demonstrate that although significant organic contamination was evident, the ground conditions at the site were favourable to limit the risk to the recognised watercourse receptor through a low permeability barrier present along the pollution pathway; and through a Controlled Water Detailed Quantitative Risk Assessment, proactive remediation targets were developed to focus mainly on source removal within the Made Ground but with treatment of the hydrocarbon contamination within the groundwater.
A remediation strategy was developed to meet these targets through application of Sustainable Remediation Forum initiatives, whilst also considering the operational needs of the site. This led to a proposal for a combined remedial approach, with localised excavation and disposal of the main contaminated area; ex-situ pump and treat of the perched groundwater within the made ground; localised oil skimming to reduce free phase oil; and monitored natural attenuation of the aquifer to monitor improvements against the remedial targets.