To ask the Secretary of State for Environment, Food and Rural Affairs, whether sewage was released into the chalk aquifer in Caddington in (a) 2022 and (b) 2023.

Caddington sewage treatment works has a discharge permit to discharge treated sewage effluent to ground. The permit states that the discharge must consist solely of treated sewage effluent and that the point of discharge is to ground via a soakaway. The borehole soakaways infiltrate into the unsaturated zone of the underlying Middle Chalk. The permit includes limiting values for the chemical composition of the effluent being discharged, to minimise the potential for pollution to arise from the discharge. This is what is known as an “indirect discharge” insomuch that it discharges to the unsaturated zone. Direct discharges to the saturated zone of the Chalk are forbidden.