To ask Her Majesty's Government whether any substance which is considered to be hazardous to (1) pollinator populations, (2) aquatic life, (3) animals, or (4) humans, is being used in the construction of the Chilterns Tunnel as part of the HS2 development.

All construction projects use substances that have the potential to cause harm if not used or controlled appropriately. All substances HS2 consider using (whether hazardous or not) are permissible within UK law and are subject to detailed risk assessment to assess the potential risk they pose.

With respect to construction of the Chilterns Tunnel, substances are reviewed by the Environment Agency and Affinity Water who are required to provide their consent before use. Their use is also subject to appropriate site management and monitoring regimes to avoid adverse impacts. This includes assessment of groundwater to determine if any substances are present at a concentration that could represent a risk.

All substances have been selected based on their suitability for their primary purpose and the specific environmental sensitivities of this location. Risks are assessed as being low because of how and where the substances or materials will be used. There is no pathway from the substances used during tunnelling activity to pollinators, whether or not a substance being used is deemed hazardous to them. No significant risks have been identified to aquatic life or animals with the substances to be used.