Cognition’s key responsibilities on Phase 2 of the project include:

• Vegetation removal from viaduct wall: Vegetation will be removed from and around the previously inaccessible viaduct wall.
• Stockpile movement from Phase 2 to Phase 4: Relocation of 15,000m3 of Class 6F2, previously produced by Cognition under the EA Quality Protocol, from Phase 2 to Phase 4 for later use by St William.
• Probing pile positions up to 5m: Obstruction probing within previous viaduct exclusion zone along perimeter sheet pile line to a depth of 5m.
• Removal of Network Rail viaduct wall: Removal of the redundant brickwork facing wall to the Network Rail viaduct along the western site boundary. Methodical, top-down removal of the wall in arch-wide sections using handheld tools working from MEWPs.
• Turnover of soil for lift pits/cores and load transfer platform: Deeper soil turnover (to 3.0mbgl) than that previously carried out (1.5mbgl) is required for specific, previously inaccessible areas of the site including a load transfer platform above a strategic sewer and the Elizabeth Line.
• Pile mat installation: Construction of a pile mat for Zone 2 piling works and for the sheet piling works. Our intention is to reuse site-produced aggregates and compaction testing will be carried out at formation level and following pile mat installation to confirm bearing capacity.
• Sheet pile installation: Pre-augering and installation of sheet pile wall along line of viaduct using vibrationless Giken method.
• Pile attendance: Removal of sheet pile and load bearing pile arisings and placement in Phase 4 gasholder following testing for suitability for reuse in accordance with the approved Remediation Method Statement and DoWCoP.

Cognition is deeply committed to the quality, safety and sustainability of our project delivery. We will complete this project with the upmost consideration for the community and the environment. Special considerations necessary for this project include: borehole and sheet pile management, people/plant interface, dust/asbestos/vibration monitoring, and co-ordination with Network Rail/TfL/Thames Water due to the proximity of our works to rail and sewer infrastructure. Cognition will ensure risks are mitigated for the safety of our team and the community.

Cognition has a history of working on this site. From October 2022 to June 2023, we were commissioned by St William Homes to undertake the contamination remediation, ground obstruction removal, materials management, earthworks, pile mat construction and associated groundworks to support the proposed redevelopment.

The remediation, earthworks and infrastructure works were completed to time and budget, with all stakeholders fully engaged and informed, including local residents. Cognition’s approach to the works was to minimise disposal and maximise reuse of excavated soils and demolition at the site. Over 60,000m3 of material was remediated, processed and reused on site with an over 98% reuse rate. The site was regularly audited by regulators and client representatives who were impressed by the dedication and professionalism of the Cognition team in all areas of technical, quality and safety compliance. An Environment Agency inspector stated:

“The Bow Common site is one of the best I have visited, being managed very well. We were really pleased to hear about all of the proactive engagement that has been carried out with local residents. If all future sites at this stage are presented and managed the same, we will be very pleased.”

We look forward to working collaboratively with St William/St James and the rest of the team at Bow Common - Phase 2, on this transformative project!