500 tonnes of illegally dumped waste, including asbestos, has been cleared from the former Lucas Aerospace site in Hemel.
Tippers dumped the rubbish over a 10-day period, and it took a week for emergency waste specialist WasteSafe Services to clear the 15-acre area.
Waste included broken furniture, old kitchen units, builders’ rubble and household waste, and a man was seen sitting on a chair at the entrance, charging people as they drove truckloads of waste in to be dumped.
Martin Bull, director of WasteSafe, said: “This is the worst case of fly-tipping we’ve ever dealt with.
“The scale was quite amazing to see. The fly tipping was clearly co-ordinated to fill the site with as much waste as possible.
“Those controlling the site will have made thousands of pounds, while the fly tippers avoided regulations and more substantial fees associated with official waste sites.”