There is so many issues with this site:
Transport links: heads of the valleys is basically a car park during rush hour, down to one lane by gilwern/Abergavenny. The other side by hirwauen is a single carriage road. So the only way is to come up through Cardiff and up the valley. Big traffic jams around castle coach.
Weather: I work around that area, it's either ******* it down all the time or the cloud is very low. So helicopter /drone camera work is going to be poor.
Gas pipeline: there is a major nationalgrid transmission pipeline in on the course, this pipeline was installed in the 70s and is not a twin wall so the project would have to pay for the pipe to be dug up and sleeved, not cheap.
Accommodation: there is nothing nearby only Merthyr at that's not exactly pretty.
Iron Age/ Bronze Age settlement. There are multiple settlements in the area, not sure how they plan to deal with that.
Instead they could invest in pembrey, it has a airfield lots of accommodation. Pre existing contracts. Only thing it needs doing is traffic links. Roads are single lane from either Llanelli or Carmarthen.
But to be honest this is just a we need a race circuit near Cardiff as Cardiff needs everything