A small yet complex demolition contract involving the demolition of a petrol station kiosk and canopy, and the decommissioning of eight underground fuel storage tanks and the associated pipework at the entrance to the busy Sainsbury’s superstore on Hyde Estate Road in the London Borough of Barnet as part of the Silk Stream development for St. George (part of the Berkeley Homes Group).

The canopy oversailed the public walkway and road into the shopping centre, which pushed the planned exclusion zone out resulting in the requirement for a partial road closure during the first stage of the works.

Other challenges came from the river, the Silk Stream, which was in close proximity to the site, which caused an initial issue with planning and the reduced level dig and the potential for hydrocarbon leachate polluting the water course.

The underground fuel tanks were decanted and degassed in line with the APEA blue book guidance in which we had to maintain a constant liaison with the London Fire Brigade Petroleum Officer to comply with the licensing requirements for the removal of the tanks. The site also housed a hydrogen fuel dispenser which was removed as part of the works.

Site overview video:

We were appointed as the demolition consultants for the project and then we took over the role of CDM Advisor for the demolition phase of the project. We first checked the content of the Pre-Construction Information (PCI) documents supplied by the Principal Designer and offered feedback on the documents and assisted in its development before distributing them to the contractors.

We attended the pre-appointment meetings with the client and provided feedback on the tendering contractors to rank the bidders based solely on the quality of the submissions to ensure the best contractor was selected.

A further high-risk package review meeting was carried out with the successful contractor prior to the pre-start meeting. The meeting involved both the contractor and the client to further focus on the specifics of the site.

Once the contractor’s Construction Phase Plan (CPP) was completed, we were tasked with reviewing the plan and the Risk Assessment and Method Statement (RAMS) for the project and continually commenting on the revisions and updates of both sets of documents.

Throughout the works, we carried out monthly audits which were planned to coincide with the specific phases of the project, which included specific environmental audits, CDM compliance audits, and process-specific demolition audits.

• Produce the Pre-Construction Information.
•  Produce the Designer Key Hazards.
• Carry out a Pre-Demolition BREEAM survey.
• Carry out a Pre-Demolition building stability report.
• Carry out a consultation on the tender list.
• Review and comment on the Construction Phase Plan.
• Review and comment on the Risk Assessments and Method Statement and issue a report.
• Carry out the pre-start site audit and issue a report.
• Carry out monthly site audits and issue a report on the progress.
• Carry out the completion site audit and issue a report.
• Ensure the completion of the Health & Safety File.