This particular project was undertaken in an area that housed four mineshafts in close proximity to the demolition area with a local canal adjoining the site. Mindful of these factors and the historic interest, the protection of the surrounding mineshafts and environment was of vital importance and our aim was to minimise and preferably avoid any further degradation whilst also ensuring Health and Safety of all site personnel remained a top priority throughout the project.
The site was previously an operational Gas works which was constructed in 1829, however the waterless gas holder that we were appointed to carry out the demolition of, had only been in existence for some 60 years, having been constructed in the 1930s before falling into disuse.
Client: Trans Co
Contract: Explosive demolition and clearance of redundant Gasholder
Contract Date: 2003
Contract Value: £ 200,000.00
The project included the complete removal and site clearance of the 275ft structure. All preparation works were undertaken by our experienced site team, including the removal of the tar, water seal, removal of the piston by ultra-high-pressure water cutting, tar pumping and disposal.
Our team of experts advised the client, Transco, that the most effective method of demolition would be by explosives. Our explosives engineering experts undertook the explosive demolition of the structure before processing the arising material at ground level.
Processing works included removal of the timber and asbestos roof structure, and recycling of the steelwork and concrete foundations. Ground works were also undertaken to infill the basement excavations and to level the site by reusing the recycled crushed concrete that had previously been the foundations.
Explosive demolition proved to be the safest and the most efficient method, considerably reducing the project timescale.
Preparatory works included thorough analysis of the structural engineering and involved a ‘test blast’, a procedure intended to establish the quality, performance and reliability of the explosives. This enabled us to determine factors such as final charge weights, vibration, predicted debris area, respective exclusion zoning and air pressure studies.
Blade explosives were used to promptly demolish the 1,000-tonne structure. The resultant arising materials were processed and removed from site within a 14-day period.
Residual tar, water mixture, oils and other hydrocarbons were present both within the structure and below the gas holder. Industrial cleaning of the tanks and cabins was undertaken using a combination of high-pressure steam cleaning and vacuum suction methods. Under strict confined space entry, the residual tar was then mechanically removed by the excavator.
All waste materials were handled inline with the ‘Waste Duty of Care: Code of Practice’ and appropriately disposed of.
The site was fully cleared and handed back to the Client to enable a £5 million regeneration project for the area, including a 40-bedroom hotel and pub-restaurant complex to be built, creating up to 200 jobs in West Bromwich.