Residents described how about 30 lorries delivered hardcore materials under the cover of darkness as work began on Friday.
Speaking anonymously, one said: “It felt like a military operation. The sheer scale and enormity of it is breathtaking.”
They added: “They have ploughed through with no apparent consideration for wildlife, ecology, pollution, drainage – all of the things that need to be taken into account when you are developing any site.
“It’s just railroaded, and that’s unbelievable.”
Drone images taken at the site show what appears to be individual, fenced-off plots being created on the concreted land.
Tracy Williams, who has lived nearby for a decade, said people had been “really upset, scared, intimidated” about what was going on.
“It just feels really frustrating and uncomfortable,” said the 42-year-old.