Located in Salisbury Plain Training Area, the MOD site is the British Army’s largest national training area, which comes with its own complexities due to its proximity to the Stonehenge World Heritage site. As part of the Ministry of Defence Army Basing programme, the Larkhill site was identified to relocate Army units from Germany and provide 540 new homes by 2020.
For several years, the site had been used for live fire training and required a series of UXO (unexploded ordinance) checks and controlled on-site explosions. Once the ground had been stripped, a series of First World War training tunnels and practice trenches were revealed. The tunnels were part of a First World War battlefield, used to train men to fight in (and under) the trenches of France and Belgium. In addition to the mine galleries deep in the chalk, the project discovered over a hundred inscriptions written by soldiers who trained at Larkhill between 1915 and 1918.
In addition to the tunnels, a wealth of prehistoric remains has been discovered, including a Neolithic enclosure some 600 years older than Stonehenge, and 4,000-year-old burials.
Cundall was initially appointed to provide advice to the client and design team on how to gain safe access to the tunnels for archaeologists and UXO specialists, as well as recording 3D scanned data using remote operating vehicles (ROVs).
Cundall’s alternative proposal of using innovative integrated surveying techniques led to a further appointment to devise and manage a phased approach by carrying out geophysical surveys using conductivity and resistivity, along with opening tunnel entrances and laser scanning the tunnels. Cundall will also assist with the development of a strategy for stabilising the ground.
Throughout the project, tunnel data is being obtained in 3D and being combined with other data and information to create a 3D interactive model of the tunnel network. This is under construction and development as the survey progresses.
The team have had to deal with many complexities on site, including over 100 live hand grenades. (A cache of 40 was found in one recently exposed tunnel entrance alone.)
Cundall has worked alongside the project stakeholders, including archaeologists and specialists.
Jim Allen, Partner and Head of Geotechnical Engineering at Cundall said: “Cundall has played an important role in this sensitive and significant project. As well as using innovative surveying techniques to locate and map this previously undocumented network of WW1 tunnels, Cundall has also provided the project archaeologists with safe access into structures undisturbed for the last 100 years. The extensive tunnel remains revealed are testament to the incredible skill and bravery of the miners who constructed them, and soldiers who trained in them before facing the horrors of the western front.”