A sinkhole above the HS2 tunnelling works in Buckinghamshire is being investigated by the government for ‘pollution’.

The Environment Agency has launched a probe into the 6m (20ft) wide crater-like sinkhole.

It opened up above the Chiltern tunnel next to the Shardeloes Lake in Amersham on Saturday (May 13). 

Campaigners have called for the controversial high-speed railway works to stop, citing concerns over the safety of the aquifer supplying millions of people with water. 

An Environment Agency spokesperson said: “We are investigating a sinkhole on private land near Amersham in Buckinghamshire, to understand whether it has resulted in any pollution to the local environment.

Bucks Free Press: River Misbourne flows through the picturesque Shardeloes Lake River Misbourne flows through the picturesque Shardeloes Lake (Image: Chiltern PhotoGroup/ K Hoffmeister)

“Our specialist officers work closely with HS2 Ltd and contractors to ensure all relevant legislation is followed.

"We also continue to talk to local people, the water industry and local authorities to ensure the environment is protected throughout the HS2 project.

“Anyone with new concerns about this incident can call our 24-hour incident hotline: 0800 807060.”

Two giant tunnelling machines have been excavating the 10-mile Chiltern tunnel under Buckinghamshire countryside, which is largely made of chalk and flint material, since 2021.