Like you say hoehlenforscher, we'll have to wait and see. The Environmental Statement makes it sound like the caves would be protected and/or avoided but the widened road would pass right over Caple which is at a shallow depth.
Could cavers, through CCC or BCA, make representations to the powers that be, for protection of the caves during construction and continued access after completion. Is it already too late for that? I seem to remember that most of the previous opposition was directed at getting the dualing scheme abandoned altogether through the gorge.
Something else to think about is that the construction works may very well open up new caves! Surely cavers should be given the chance to investigate these. Would it be possible to persuade the contractors to then maintain access to any significant discoveries? Another area where construction of the wider road may turn up something new is at Cefn Coed in Merthyr. In fact some small caves were found here when the cutting was made through the ridge when the original, three lane, road was built. I believe that cavers were allowed to investigate the caves then but that the entrances were subsequently closed up.