VILLAGERS objecting to plans to create a giant quarry close to Oxford said they were furious the Environment Agency had backed the proposals.
Hanson Aggregates wants to extract 1.55m tonnes of sand and gravel from a site the size of 40 football pitches at Stonehenge Farm in Northmoor.
The company plans to transport the raw material on a conveyor for processing at its site at Stanton Harcourt.
But residents in nearby villages said they were desperate to prevent another gravel pit appearing in the area.
They said the land was prone to serious flooding because it was at the junction of the rivers Thames and Windrush and another quarry would make matters worse.
Julie Hankey, chairman of Outrage (Oxfordshire Upper Thames Residents Against Gravel Extraction), said: "The company can't guarantee the flood risk won't be increased by the development.
"A very large part of the Windrush Valley has been devastated by the gravel industry over the last 50 or 60 years.
"There's a growing feeling among people that enough is enough, especially since last July's floods. We don't feel safe."
Tory county councillor Charles Mathew said: "This is a very vulnerable spot to be interfering with the flow of water, with serious flooding implications in Northmoor and possibly downstream at Bablockhythe."
West Oxfordshire District Council and the Campaign to Protect Rural England have also objected to the application.
However, Hanson spokesman David Weeks said extensive research had been carried out over the last four years and two public consultations held.
He said expert opinion contradicted residents' concerns and the materials quarried at Stonehenge Farm would be used locally.
He said: "We are confident there is no reason to be concerned and these fears will prove to be misplaced.
"We have employed people who are experts and we have a comprehensive report. We have worked very hard and are confident the application will go through."
Environment Agency spokesman Maria Goodall said: "We have held meetings to address the concerns of the local residents.
"We have raised no objection as we are satisfied the additional work carried out by the applicant at our request addresses our concerns on flood risk and hydrology."
Oxfordshire County Council is set to vote on the application on Monday.