Docklands: Contamination and Geotechnical Challenges
Introduction:
Multidisciplinary contamination and geotechnical fast track team input to discharge outstanding planning conditions that restricted development. Our studies included Controlled Water Risk Assessment, a Preloading and Surcharging Strategy and an overall Foundation Strategy Review.
The development comprised 2,000 new homes together with a host of local amenities for the area, including cafés, bars and restaurants, shops, a new primary school, parks and play spaces. A new link road and retail superstore were also key to the overall development proposal.
We combined available historic studies to conclude assessment of risks to controlled waters and agree remedial objectives. This overcame multiple regulator objections to allow remedial works and development to commence. A foundation strategy review and development of preloading/surcharging strategy to mitigate high settlement allowed the development program and contractor sequencing to be finalised so that the site preparation contracts could be agreed.
Details:
This large dockland site has a significant history, having been a former estuary that was dammed and infilled to create docks from the 1880’s and over time was used as railway land, bulk oil storage/tank farms and railway yards.
A significant amount of investigation and risk assessment had been undertaken across the former docklands and we were subsequently appointed to review and coordinate the available reports and findings to discharge planning conditions and refine project sequencing that would allow the development to commence.
Supplementary site investigation, sampling and testing of soil, soil leachate and groundwater was required to fill in gaps, update and finalise the assessment of risks to Controlled Waters. This included contaminant fate and transport modelling and derivation of remedial targets and objectives. Contaminants of concern were refined and organic pollutants generally identified as the compounds requiring action to reduce environmental risks and liabilities.
The development now comprises 2,000 new homes together with a host of local amenities for the area, including cafés, bars and restaurants, shops, a new primary school, parks and play spaces. A new link road and retail superstore were also key to the overall development.
Supplementary investigation using Cone Penetrometer Testing (CPT) and dissipation testing assisted estimates for consolidation settlement magnitudes, settlement durations and design of a strategy to accelerate settlements so that the development sequencing could be finalised (shown above).