THOUSANDS of motorists would face delays under plans to reduce a dualled stretch of the A420 to single lane to allow a sand extraction operation.

The proposals by Hanson Aggregate, which wants to extract the sand at Longworth, include cutting half a mile of the eastbound dual carriageway from two lanes to one.

The company is also seeking to reduce the speed limit from 70mph to 50mph over 1.36km in both directions, which would affect an estimated 18,000 motorists a day. Hanson, which wants to extract 1.1m tonnes of sand over ten years from land off Pine Woods Lane, claims the changes are necessary to allow safe access to the lane by 40 HGVs a day.

But residents and MP Ed Vaizey have reacted with outrage at the plans.

Alan Boyce, chairman of Longworth Parish Council and pressure group Land not Sand, said: “The concern is 18,000 motorists a day will be inconvenienced and a dangerous junction will be made even more dangerous for the sake of a small number of HGVs and one commercial operator.

“It’s not just nimbyism — this is a busy county road of national importance.

“We want the county council to look at other more practical quarry sites in Oxfordshire.”

Fellow group member Prof Adam Ogilvie-Smith, of Longworth, said: “This proposal will make the road more dangerous for many reasons. Cars will not heed the speed limit because it is the last chance they have to overtake before 14 miles to Swindon. Also, the sight lines are terrible so HGVs will be gambling when they cross the road. While they are waiting for a gap in the traffic it will cause horrendous tailbacks.”

Hanson plans to cut half a mile of the dual carriageway to a single lane for drivers coming from the west up until the Pine Woods Lane junction. The lower speed limit would be either side of the junction.

Mr Vaizey said: “This is one of those mad schemes that has been in the pipeline for so long that the county council planning officers have stopped asking why it’s necessary or what the consequences will be because they are so determined to get it through. The idea that we would close a lane on one of the county’s main roads to allow a company to let its lorries pull out is ridiculous. The council needs to stop this barmy proposal immediately.”

The quarry excavation application was first lodged in 2007. Since then it has been revised four times to deal with worries over road safety.

Hanson spokesman David Weeks said: “Ideally, we would not have the closure of the lane but that’s what officers at the county council have told us to do in order to get approval.”

He said: “In some respects, we share the community’s concerns but we have put hundreds of thousands of pounds into the project and the important thing for us is to secure planning permission.

“We don’t want it to fall at a hurdle because of safety.”

Oxfordshire County Council spokesman Paul Smith said the issues raised would be discussed when the application came before the council’s planning and regulation committee meeting on Monday, November 23.