BWB Consulting - Integrated Engineering and Environmental Consultants

Services:

• Environmental and Geotechnical Due Diligence
• Ground Investigation, Geo-environmental Risk Assessment
• Rock Slope Stability Assessment
• Foundation and drainage design
• Remediation Design, Supervision and Validation

Sectors:

• Industrial
• Residential

BWB provided geotechnical and environmental consultancy services for the residential development at a former furniture factory and landfill in Nottingham. BWB provided environmental consultancy services for the land owner during divestment. Due to our working knowledge of the site BWB were subsequently appointed by the housing developer to act as consultants during site clearance, remediation and final validation of the site.

The site was originally part of a railway cutting. The southern half of the site was found to be heavily contaminated by degraded oil and diesel, whilst the northern part was used as a landfill for textile and other wastes. BWB produced a remediation strategy for the site which was presented to and agreed with regulators as part of the planning process.

The potential for gas generation due to biodegradable waste in the landfill area necessitated its removal. BWB provided geotechnical consultancy support during the production of the earthwork strategy and subsequent supervision of the demolition and earthworks contractors during excavation of landfill materials, separation of textiles from the soil matrix to minimise off site disposal, grading of the soil and re-grading of landfill area of the site to provide a level building platform. The landfill material extended to a steep rock slope at the northern end of the site on top of which was a road. BWB undertook a stability assessment of the rock slope and provided a working method statement for the safe removal of the fill material up to the rock face without threatening the overall stability of the slope and road. Ground improvement techniques comprising vibro-stone columns were used to improve the loose filled areas, in order to facilitate the use of traditional spread foundations for houses and flats.

BWB undertook in-situ permeability tests on the near surface granular materials in order to facilitate soakaway drainage design.

The contaminated soil was removed from site and replaced with clean imported soil. Following remediation works and regrading, the site was subject to chemical validation testing of the soils and gas monitoring to ensure the remediation had been successful and allow sale of residential houses on a plot by plot basis as and when they were completed.