Maple Cross residents fighting plans to turn Green Belt land into a quarry fear there could be "an environmental disaster" if the planning inspector rules in favour of the proposals.

Plans to extract minerals and process sand and gravel on land at Pynesfield, off Tilehouse Lane, were unanimously thrown out by Hertfordshire County Council’s development control committee in January. 

But the applicant, Harleyford Aggregates Limited, appealed this decision and dozens of residents packed into Three Rivers District Council on Wednesday as the planning inspector, Jonathan King, heard representations from both sides.

The Pynesfield area, which is situated 200 metres from Denham Park Farm, is part of the land safeguarded for HS2 and if planning permission was granted by the planning inspectorate, the area would have to be restored by the time "HS2 needed the site."

Residents in West Hyde and Tilehouse Lane expressed concerns over the increased level of traffic and fears over flooding if the controversial plans were passed.

One resident, David Griffin, told the hearing: "What the appellants are proposing is to extract the permeable gravel and replace it with less permeable clay. 

"What happens when rain falls on gravel is it passes through onto the chalk and then it will reach the water table.

"But with clay, which is less permeable, it cannot do this and will run off the slope to the lowest land near-by, in this case, West Hyde.

"Most of us here are concerned about the plan to replace gravel with clay and the water running off on to our properties."

Sylvia Ball, resident, added: "We fear an environmental disaster."

But Douglas Symes, speaking on behalf of the applicant, reiterated that if planning permission was granted, provisions would be put in place to retain the water "on site" and there would still be gravel in place to drain the water.

Representations made by the Environment Agency expressed concern over the potential contamination of ground water as representatives from both sides clashed over the possible effect of digging up an old canal.

Mike Fosberry, of Tilehouse Lane, said: "The A412 in this area, I think we had confirmed today by Ann, [Ann Shaw, leader of Three Rivers District Council] is the most dangerous road in Hertfordshire, we have had four fatalities in the recent past. 

"We are concerned for for the people living locally because of the traffic in the area. 

"We are concerned for the safety of our children who are going to school because there is no pavement on many of the roads.

"We are a strong community and we are united in opposition to the application, we do not want it and we hope you reject this application."

Yet Mr Symes indicated that the majority of the lorries would not be moving during rush hour and said that there would not be a drastic rise in the number of lorries on the A412, which residents claim is regularly used as a relief road when there are traffic problems on the M25.