Campaigners fear a proposal to extract eight million tonnes of gravel from a former aerodrome site will lead to the contamination of underground water reserves.

A planning application is due to be considered by Hertfordshire County Council's development control committee to develop a new gravel quarry at the former Hatfield Aerodrome site.

Ellenbrook Area Residents Association - backed by St Albans MP Anne Main - is concerned the proposed development in Smallford could disturb underground plumes of the carcinogenic chemical bromate and cause the chemical to enter underground water reserves.

The group said there could be a major environmental impact and there is already a lack of water in the area.

It has a slammed a groundwater quality data set published by independent construction group Brett in August, saying the report is “misleading”.

Data recorded in February suggests no bromate compound was detected from boreholes in the ground, the residents association said.

But the group said Brett had used different measurements which made the concentration seem diluted, when it had in fact exceeded World Health Organisation recommendations.

St Albans & Harpenden Review:

Anne with residents during her visit to the Hatfield Aerodrome site. Photo: John Andrews.

Spokesperson John Jackson said: “Our current concern with the Bromate is the environmental damage that this application poses to the scarce water resource used to supply the public.

“This will mean we have no usable resource within this area, thus further affecting public supplies.

“There are already at risk of restrictions being imposed next year due to shortage and a hose pipe ban is expected to be introduced early next year. "

Campaigners are calling for an up-to-date report and an independent investigation.

MP Mrs Main who is standing behind the group has also called on the Prime Minister to ensure Environment Agency does not allow the development of a quarry.

A spokesperson for Brett said: “Hatfield Aerodrome has been identified for quarrying in the county's minerals local plan for a number of years and the location is the subject of a planning application currently being decided by the county council.

“The application is supported by a full environmental assessment, and as part of this process we have provided the authorities with the latest environmental studies, including assessments on groundwater quality."