Each tunnelling machine weighed in at 1,000 tonnes,  each being a 150 metre long underground factory with 20 person ‘tunnel gangs’ working in shifts.

At peak, the tunnel boring machines aimed for around 100 metres of tunnelling progress per week - as the tunnelling machines move forward, precast concrete segments were built in rings behind - 250,000 tunnel segments were used to line the 42 kilometres of tunnels.

4.5 million tonnes of excavated material from the tunnels has been shipped to Wallasea Island in Essex where it has been used to create a new 1,500 acre RSPB nature reserve.

RFS carried out unloading of box wagons to stockpiles on a 24/7 operational basis.

We utilised  Volvo 480DMH and Liebherr R944EWMH material handlers with 2500Ltr clamshell grabs for the unloading of London clays from rail wagons operated by GBRF.

Unloading  works consisted of 5 to 6No 1200t payload trains per day along with placing materials to stockpiles, production peaked at 7200t per day.