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Twll Gwynt Oer

A Significant Find in South Wales

Having watched the rapid advance of the quarry towards OFD, some members of SWCC decided to take a closer look at some of the shakeholes in the dry valley above the quarry.  The drainage of this region has already been proven by dye testing to feed into the OFD system.  To his surprise Brian Jopling found a hollow that gently breathed cold air.  Cold air hole was fairly intensively dug out over the Easter weekend and later in the week a little Mendip digging fever saw to the breakthrough into a small, fault-aligned passage carrying a sizeable stream, whose sound had previously urged the diggers on.

Upstream has not yet been forced to any conclusion - the size of the stream during the dry conditions prevalent in South Wales at the moment suggests considerable development upstream.  The results of dye tests (a week after Easter) will surely suggest a connection with Cwm Dwr.  On the downstream end.  Unfortunately the way on along the fault is blocked by the debris in the now 50 foot deep pothole that has been revealed by emptying out the shakehole.  The water appears to go round this obstruction in a very low bedding plane.  It is believed that the route onwards will be found by completely emptying the pothole of its glacial fill, and the way will continue via the fault.  Cwm Dwr Jama is some 250 feet lower (my guess) so there must be considerable vertical development downstream, hopefully not in an impenetrable narrow rift.

Whatever happens, it shows that OFD is not finished yet.  While on the subject, may I be bold enough to suggest that the new survey will prove OFD to be nearer 30 miles in length, and not just over 20 miles, as usually quoted.

Access Problems

Visiting the area around Y Gwal and The Hole by the Wall (Hutton Pot) just above Ystradfellte, recently I found that the top of the latter had been almost blocked with very large boulders of grit.  I spoke with the farmer about this and he confirmed that it was his doing, in order to prevent calves becoming stuck in the hole.  He was unwilling to have it re-opened and a fence erected around the site, as cavers rarely returned every so often to maintain and repair such fences. He pointed to the gaping hole of Y Gwal, which had been fenced around by Cardiff University (pseudonym for a more well known Speleo. Soc.?).  The fence was rusted and decrepit.  The farmer had erected a new fence around the old one, and reckoned he would have to replace this every couple of years.  What is the solution?

In Yorkshire at Easter we wanted to look at the Red Moss system. The owner at the farm noted in Northern Caves told us that he did not wish to be asked for permission (he had told CNCC this).  He understood that if he granted permission he could be more liable in the event of accident.  However, what we did on his land was our affair, he implied, so long as he knew nothing about it.