THE CHALLENGE:
Remediation and enabling of the 1.1Ha former dye factory site in West London was required to facilitate a mixed-use development including a new special education needs (SEN) School. The former site use meant that there was surface, sub-surface obstructions and foundations that required removal before piling. Furthermore, removal of a large hotspot contaminated with hydrocarbons was also required.
A sustainable remediation solution was required by the client, to create a geotechnically suitable development platform to its D&B Contractor’s construction formation levels, with off-site disposal reduced to a practicable minimum.
OUR SOLUTION:
Soilfix designed and implemented the following complex remediation & enabling works scheme over a 14-week period, fully in accordance with CL:AIRE Code of Practice:
- Controlled demolition of perimeter wall and installation of perimeter site hoarding;
- Bulk excavation of materials in accordance with the cut and fill model, along with associated materials management. Approximately 12,500m3 of material was excavated;
- Slab-breakout and proof dig down to natural subsoils or to 2m from original ground level to remove obstructions left from former infrastructure;
- Screening and sorting of approximately 4,250m3 excavated made ground;
- Re-use of suitable materials to reinstate excavated areas to agreed levels;
- Hotspot excavation and off-site treatment of hydrocarbon impacted soils fully in accordance with Duty of Care;
- Off-site disposal of contaminated water from hotspot excavation;
- Exhaustive environmental monitoring and controls, continually communicating with key stakeholders;
- Segregation of natural subsoil for future re-use as a landscaping capping material; and,
- Placement of 6F2 crush running layer across site to form a piling / development platform layer.
Soilfix successfully completed all works to budget and on programme with zero lost time accidents, enabling timely sign-off of the remediation strategy and achieving >98% materials re-use.
