Sustainability 26 April 2019

Sustainable Waste Management: Kettering Electric Stablings

Construction, demolition and refurbishment accounts for around 100 million tonnes of waste in the UK each year, according to the BRE (Building Research Establishment). When the team working on the electrification of the Midland Main Line found that they had to remove 26,000 tonnes of material from a site in Kettering before construction could begin, they took a more sustainable approach to waste management. As a result, they diverted 100% of waste from landfill and saved money.

Benefits at a Glance:

  • 100% diversion from landfill of 26,000 tonnes of spoil
  • Use of hybrid plant to optimise fuel efficiency and reduce carbon emissions on site
  • Helping to reuse and recycle excavated waste
  • Reducing non-traction carbon emissions
  • Reducing particulate (air quality) emissions

The Kettering Electric Stablings (KES) project involved the construction of appropriate stabling and Controlled Emissions Toilets (CET) facilities for up to four 12 carriage electric trains, due to enter into service on March 2020. KES is critical to enable electric trains to run between London and Corby.

The project team inherited a site that had been littered with discarded material over several years. Their first step was collect, segregate and dispose of this material using a licensed waste contractor. A local contractor with a waste treatment facility close by was chosen to remove the spoil as this reduced costs and reduced the carbon footprint of the works. .

Hybrid excavators worked 8 hours a day over seven months to successfully remove the soil.  On average, a hybrid excavator cuts fuel consumption and carbon emissions by 19%. This is achieved by energy regeneration during slewing operations where the energy is stored in a capacitor and in turn can be used to slew or help the engine accelerate.

Results

  • Carbon emissions reduced by 11.3 tonnes through the use of hybrid plant
  • A safer site as machine operators were able to closely monitor their exclusion zone using four built-in high definition cameras and wearable warning alarms
  • The total embodied carbon of the spoil removal process was reduced almost tenfold because the waste facility for the local company was less than a mile and a half from the KES site. This resulted in fewer lorries hauling material off site and a shorter journey between the site and the recycling facility
  • 100% diversion from landfill. The local contractor cleaned and filtered the granular material taken off site and reused it in construction activities such as drainage pipe bedding. The clay material taken off site was stockpiled and will be used on projects in the local area to provide noise bunding (i.e. to contain noise) and environmental features such as an embankment on a golf course

 

Lessons Learned/Best Practice

  • Embedding sustainability into site waste management can massively reduce environmental impacts
  • Collaboration, communication and accurate cost benefit analysis is critical to making informed decisions which achieve project efficiencies and sustainability benefits

 

Further Reading:

  • Midland Mainline programme sustainability strategy

 

Work to clear spoil at Kettering electric stablings