Hi Dan, Can't say I saw the adit. You mean actually at CC rather than Gilfach?
With regard to the Penmorfa article, I'm not convinced CC pumped Gilfach. True, there aren't any tailings on site, but the shaft (at least in it's restored interpretation) seems to have been both a pumping and winding shaft. Also the shaft is flooded to about 10' below shaft collar, so if linked to Gilfach at depth there would be a substantial head of water.
It's an interesting site, and not a straightforward one either. I'll have a look at Bick tonight. Not much info on the interweb.
Cheers,
Robin