The Sheephouse Wood Bat Protection structure in Buckinghamshire hit the headlines last year when it was revealed construction will cost £100m to protect a colony of Bechstein’s bats from passing trains.

BAM has been reviewing labour supply agreements on HS2 where it is part of the EKFB consortium.

The move follows Balfour Beatty’s decision earlier this month to terminate all labour supply deals with Danny Sullivan Group after HS2 launched an investigation into allegedly overinflated rates charged by the firm for labour on the West Midlands section of the project.

The probe examined claims that self-employed workers were being charged out at PAYE rates.

HS2 is continuing to conduct further investigations into labour supply contracts across the project and HMRC has been contacted.

A BAM statement said:“BAM UK & Ireland has taken the decision to end Danny Sullivan Group’s involvement on projects where compliance issues have been identified. This follows an internal review of our labour supply arrangements, which remains ongoing.

“We continue to work with Danny Sullivan Group on other contracts while further investigations are carried out. This measured approach reflects our focus on responsible supply chain management.

“We remain fully committed to the highest standards of ethics, legal compliance, and workforce welfare, and are working closely with our clients and partners as we continue to monitor and review the situation.”

The Enquirer understands around 30 Danny Sullivan workers on the site will now move to a different employer.

A spokesperson for HS2 Ltd said: “HS2 Ltd takes its responsibility for managing public money seriously. We have been very clear with our supply chain partners that unethical behaviour cannot be tolerated, and we fully support them in taking decisive action.”