Excavations at the north portal site of HS2’s Long Itchington Wood Tunnel, from which a huge tunnel boring machine (TBM) will be launched that will dig under the ancient woodland in Warwickshire, have now been completed.
Since April 2020, 120 people from Collins Earthworks have worked on the HS2 site, as have a number of locally recruited plant operatives. The team has excavated 300,000 cubic metres of soil, with the topsoil and subsoils stored and separated with a layer of straw, so they can be put back in the same way after the tunnel has been built.
The company, a subcontractor of HS2’s main works contractor BBV Joint Venture (Balfour Beatty Group and VINCI Construction), deployed a total of 35 machines on the site, all utilising the latest technology to lower emissions. As well as using state-of-the-art fuel-efficient engines, with exhaust systems that break down nitrogen oxide gases into harmless elements, Collins introduced a new CAT Electric Drive Dozer and only used lorries with EURO 6 compliant engines, earning themselves Fleet Operator Recognition Scheme (FORS) Gold status in 2019 and 2020.
The 2,000 tonne tunnel boring machine is currently arriving at the prepared site in pieces from the manufacturer Herrenknecht, and will be reassembled ready to start digging the tunnel in the summer. It will take five months to dig the first bore of the tunnel, then it will be extracted at the south portal before being transported by road back to the north portal to commence the second bore.
Aiden Goggins, BBV’s construction director at the Long Itchington Wood Tunnel site, said: “The Long Itchington Wood Tunnel site is one of the project’s largest, and Collins Earthworks have worked for nearly a year to carefully excavate material which will be reused to form environmental embankments and landscape for the railway. The tunnel in this location preserves the ancient woodland, so forms a key element in how we are managing environmental impacts through the design of the railway.
“Reducing emissions and managing the impact that machinery has on the environment is a key priority for HS2 and Balfour Beatty VINCI, and we’re pleased that Collins Earthworks have introduced the latest technology in their fleet to help us reduce our carbon footprint.”
David Collins, CEO of Collins Earthworks, added: “Working on HS2 has provided our business with ongoing work through the pandemic, ensuring we can continue to support jobs for our 370 employees in the Midlands. We are delivering a start-to-finish service, encompassing site clearance, then providing the right machines and fully trained labour to carry out all project management and execution on site, as well as recycling materials for future use on the project.”
Collins Earthworks is committed to providing training to the younger generation, providing apprentice places on HS2 sites. The company continues to prepare HS2’s sites at Long Itchington south portal, Washwood Health, Bromford Tunnel portal, and at the A46, M6 junction 4 and Marston Lane, where further opportunities will also be available.
At the peak of construction on the whole of Phase One, ten tunnel boring machines – each a self-contained underground factory – will work 24 hours a day, 7 days a week. Weighing up to 2,200 tonnes, each 160m long machine will bore and line the tunnels as they drive forward at speeds of up to 15 metres per day.