Client : Vastint UK
Programme : January 2015 – Ongoing
Value : £65m
As Principal Contractor John F Hunt is currently remediating a 26 acre site which previously accommodated heavy industrial usage, their legacy comprising underground storage tanks, pipelines, ducts, pits and soak-aways in addition to the residual process plant associated with a former oil terminal, printing ink and tar works.
Significant pollution issues are present, including dense non-aqueous phase liquids (DNAPL) and contamination in the form of heavy and light hydrocarbons and asbestos in the soils.
Scope of Works
- Demolition, remediation and enabling works for the redevelopment of this 26 acre former industrial site ready for commercial, retail and residential use.
- Installation of a steam injection system to reduce the viscosity of DNAPL in order to enable the pollutant to be extracted from the underlying groundwater. Steam facilitates the clean-up of the underlying aquifer and ensures regulatory compliance.
- Solvent, hydrocarbon and PAH contamination is being treated on-site using a combination of complex sorting, bio-remediation and stabilisation techniques.
- 40,000 litres of neat DNAPL has been removed to-date from the groundwater and over 30,000 m3 of soil is being treated using sustainable techniques—making the project one of the largest remediation schemes in the UK.
- To satisfy planning conditions, site wide remediation and verification under the current Part IIA framework is required.
- Ecological protection works (Japanese Knotweed and Giant Hogweed) are also required to satisfy planning conditions.
- Following Local Authority and Environment Agency approval of a Remediation Strategy, earthworks and remediation began in January 2015 under a Materials Management Plan and Mobile Treatment Plant License.
- The objective of the project is to remediate and enable the site to ensure it is suitable for future intended commercial/retail and residential use.
- Due to the dilapidated state of the majority of structures, caused by vandalism & weather related damage, there were deleterious materials, including broken asbestos cement sheeting, pigeon droppings and fly tipped materials which necessitated specialist, controlled and monitored demolition and enabling.
- On completion of the works, the site will meet site specific clean-up criteria associated with human health protection and groundwater resources.
- The Remedial Design was adapted to include revised re-use criteria for asbestos within soils. Implementing all relevant Health & Safety and statutory requirements, impacted soils were excavated under controlled conditions. The soils were then treated on site and verified for re-use at depth below a capping layer, in full accordance with the updated design.
- In order to overcome the shortfall in recycled aggregates, and to manage the requirements of the masterplan, the Remedial Design was also adapted to allow the stabilisation and re-use of geotechnically poor materials.
- The team was able to identify re-use locations for each material type through the innovative use of Building Information Modelling (BIM).
- The team’s working practices and methodologies were adapted in light of the proximity to the site neighbours, in order to minimise any potential risk to human health and ensure the protection of the adjacent controlled waters.
- Works are currently ongoing.
- Please visit www.sugarhouseisland.com for information on this project going forwards and how Vastint UK is transforming this historic part of London.
- Video of Sugar House Island development: https://vimeo.com/sugarhouseisland/sugar-house-island-introduction