Blackburn Meadows in Sheffield, UK, was originally the site of a coal-fired power station, decommissioned in the 1970s. This project involved demolition and site preparation for the construction of a renewable power station in its place.
The proposed plant should reduce CO2 emissions by approximately 80,000t annually, equivalent to removing 20,000 cars from Britain’s roads.
Arup has been safety advisor to the project, initially for the explosive demolition of the twin cooling towers. The firm is currently Construction, Design and Management Coordinator (CDM-C) for the project to remediate or remove contaminants from the site.
In this specialist role Arup has provided a BREEAM assessor for the project, helping to ensure the safety and wellbeing of all involved during the design, construction and operation of the proposed renewable energy plant.
Civil tender package
Arup delivered a comprehensive set of tender documents, programme and management tools for the new power station design. The civil tender package included outline drawings, plant loading, scope and bill of quantities to enable a good design-and-build tender return to be assembled.
The firm’s knowledge of turbines and power systems was fundamental to the appointment of the boiler island supplier.
Arup worked in the client’s offices, providing advice on site layout, civil design, power engineering, construction methodology, procurement and programming.
The site layout was significantly improved and enhanced to optimise plant and conveyor layouts, prioritising whole-life maintenance cost and access issues.
The site has been prepared by cable diversions, cable bridges, access improvements and construction of a plinth (power island) set above flood levels in readiness for the construction of the renewable power station.
Iconic cooling towers
The iconic ‘Tinsley Towers’, cooling towers six and seven, were all that was left of the Blackburn Meadows power station after it was closed and demolished in the 1970s.
At the time of decommissioning the towers had been strengthened by mantling but had deteriorated. The M1 Tinsley Viaduct was assessed and found to be only marginally safe and usable by closure of some of the carriageway lanes. The knowledge and technology available at the time precluded safe demolition for fear of damage to adjacent structures.
Safe explosive demolition
By 2008, the increased deterioration of the towers and new skills and knowledge meant the towers could be and had to be demolished.
Arup was engaged as Construction, Design and Management Coordinator (CDM-C) and worked with E.ON and contractors to develop a system of work to allow the towers to be brought down safely.
There were many safety issues including the poor condition of the towers (which had to be pre-strengthened so they would collapse safely), the proximity of the motorway viaduct, access to the towers, and dealing with public interest and trespass.
Following planning meetings with over 12 stakeholder groups, interested parties, coordination with explosives specialists from the Health and Safety Executive and others, agreement to demolish was achieved.
The Secretary of State authorised temporary closure of the M1 motorway on 24 August 2008, and the towers were safely brought down. There were no injuries or accidents during project.