Today's decision comes after months of outrage about the plans for Rivenhall Airfield, which, subject to the decision being called in by the Secretary of State, will see more than 450 lorries coming and going each day, bringing waste from across the county and the region.
An incinerator with a 115 foot high chimney will burn 360,000 tonnes of waste each year.
Officers also revealed at today's meeting that 12 lorry loads of toxic ash would also be transported out of the site every day.
A public consultation into the scheme returned 820 responses, of which 819, or 99.9 per cent, were opposed.
No member on the county council's development and regulation committee spoke in favour of the scheme.
Their votes were tied four each, with two abstentions, but chairman, Cllr Bill Dick, dramatically sent the motion through with his casting vote.
A group of campaigners demonstrated outside county hall.
Barry Nee, from Kelvedon who witnessed the meeting with his 18-month-old daughter Molly, said: "This is a sad day for the children of Essex."