The Lydd Airport Action Group has been campaigning against the expansion of the airport.
Louise Barton told ITV News it would continue to fight the plans and expected the proposal now to be embroiled in years of legal wrangling.
"The whole nuclear safety argument has been completed disregarded," she said.
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Russia has announced that it will expel 23 UK diplomats in a deepening rift over the poisoning of a Russian ex-spy and his daughter.
Scores of flights were cancelled and drivers were warned to take care as the "mini beast from the east" swept in.
Sergei Skripal, the ex-Russian spy who was the target of the attack, and his daughter Yulia, remain in a critical but stable condition.