Manchester Minshull Street Crown Court heard that in the summer of 2015, to support the construction of the A556 bypass in Cheshire, work had started to build a pier designed to eventually support a bridge.
This involved erecting a steel cage. On 3 August, two workers on a MEWP were working on the structure, when it collapsed. The cage crashed into the MEWP, causing it to fall on its side.
The first employee sustained life changing head injuries and the second a leg fracture. A third worker nearby escaped injury by moving away just in time.
An HSE investigation found there was no temporary support for the reinforcement cage during construction of the central pier.
Costain was principal contractor and Brenbuild Limited was appointed by Costain to construct seven bridges and an underpass.
Both firms were aware the cage was visibly leaning and that workers on site had raised concerns.
Neither company recognised the inherent instability of the reinforcement cage or took measures to ensure the work could be carried out safely.
Brenbuild Limited failed to stop work to prevent injuries from the risk of collapse and to implement control measures to prevent instability. Costain failed to plan, manage and monitor construction of the central pier.
Brenbuild Limited of Scunthorpe pleaded guilty to safety breaches and was fined £80,000 and ordered to pay costs of £21,730.11.
Costain also pleaded guilty and was fined £1.2m and ordered to pay costs of £21,644.51.
Speaking after the hearing HSE inspector Deborah Walker said: “This incident could have been easily prevented and the risk of collapse should have been identified by both companies.
“If a suitable safe system of work had been in place, this incident would not have occurred, and the two workers would not have suffered these injuries.”