Site Background & History
The site was located off Pershore Street in the centre of Birmingham. The site was previously occupied by the recently demolished Silver Blades Ice Rink / Bowling Alley and prior to that by the Midland Tube Works.
It is understood that the site levels were raised prior to construction of the leisure facility using imported fill – this fill material was understood to be from an industrial source and is assumed to be the likely source of the identified heavy metal contamination on the site.
Planning permission was granted for development of an eleven-storey tower building incorporating 333 flats, retail units and a gymnasium / communal lounge.
Contamination
Site investigation showed the underlying made ground to be contaminated with heavy metals (predominately Lead 19,000mg/kg and copper 31,000mg/kg). These presented a risk to human health (ground workers and end users) and groundwater.
Remediation Works
Envirotreat were engaged to
- breakout the existing floor slab and associated foundations,
- reduce site levels in accordance with the required cut and fill,
- remove exiting foundations,
- export offsite required surplus natural soils for recycling,
- undertake all necessary “temporary works” to achieve required levels,
- treat contaminated made ground (source treatment) for reuse on site (where required) and
- provision of a piling mat for foundation works (by others)
Conclusions
On completion of the works Envirotreat
- reused all the crushed concrete slab and foundations accounting over 80% of the piling mat requirements,
- recovered / recycled 1,000tonne of natural sands & gravels
- treated over 4,000tonne of contaminated soils suitable for reuse on site.
- removed 1,000tonne of surplus made ground at a local inert waste facility.
Through a comprehensive Validation Report, Envirotreat were able to demonstrate that the remediation strategy had been successfully implemented. Achieving the prime drivers for the remediation works (the protection of human health and controlled waters). Obtain regulatory signoff and discharge of relevant planning condition. Delivering a site suitable for development.
