Middlewood Locks

GEO-TECHNICAL AND GEO-ENVIRONMENTAL SITE INVESTIGATION

Terra Firma (South) has extensive experience of the geotechnical and geo-environmental investigation of brown field sites to allow developers to comply with the requirements of Local Authority Planning Departments and the Environment Agency.

CASE STUDY: MIDDLEWOOD LOCKS, SALFORD, MANCHESTER

Terra Firma was commissioned to undertake a geo-environmental and geo-technical investigation of derelict land in Salford, Manchester, as part of a regeneration scheme for the area.

The site had a previous industrial history having been previously occupied by an iron rolling mill, railway sidings, goods sheds, The Manchester, Bolton & Bury Canal and an industrial estate.

Investigation techniques employed at the site included cable percussive boreholes, rotary probe holes, trial pits, chemical testing and gas monitoring.

Laboratory analysis of soil, leachate and groundwater found risks to human health and the aquatic environment from a variety of industrial pollutants.

A Tier 2 Groundwater Risk Assessment undertaken by Terra Firma concluded that the contaminants presented an insignificant risk to the wider aquatic environment due to dilution and attenuation within the aquifer and surrounding surface waters.

Terra Firma designed the remediation of the site which included capping of the site with 1m of inert materials, the use of a gas membrane beneath the proposed building developments and suitably designed materials for potable water supply, to mitigate human health risks.

The geotechnical investigation found difficult ground conditions comprising highly variable made ground, buried obstructions and a high risk of unacceptable total and differential settlements.

The piles foundation solution, CBR design and buried concrete classification, overcame the geotechnical constraints but maintained economical and best practice.

Terra Firma (South) was able to manage the difficult ground conditions, onerous contamination issues and sensitive nature of the site of to deliver the clients needs.