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Ogof Hasp Alyn

by Trevor Hughes

Chris Milne (WCC) and fellow WCC/CDG divers have been doing well in this cave this summer. Following on from their success in passing the 10m long sump in Aug. '82, when 200m of new passage was discovered, this summer's diving has led to the passing of a second sump and more finds.

After the B.E.C. involvement in the discovery and surveying of this cave and the first dives at the terminal sump, all by our very own J-Rat, the WCC seem to have taken the initiative here.  I was therefore rather pleased when Chris suggested that I join him and others on a pushing trip on the August Bank Holiday weekend.

Progress prior to the planned trip had been the passing of the 4m long second sump to an ascending passage leading to the base of a 12m free climb.  From the head of the climb a roomy horizontal passage ends after 30m in a large, 16m deep pot.  At the bottom of this a passage leads off to a 25m shaft which had not yet been bottomed.

A strong team gathered on the Saturday morning, heads slightly (or more so) awash from the previous evening's ale in the Loggerheads.  Mendip was represented by Chris Milne, Anne Lavender, Paul Whybro, Kev Clarke (both of Bath University C.C.) Rich Websall, Wormhole and myself, while the local talent included Phil the Miner (also B.E.C.) and three N.W.C.C. lads who provided valuable assistance carrying ladders down the cave.

Although in places very muddy the trip to the sump is quite sporting, involving a considerable amount of ladder work, not to mention numerous flat-out crawls, wallows and a chest deep canal interspaced with undulating, walking passage. Unfortunately the trip to the sump proved to be too much for Wormhole's diving kit (where have we heard that one before?) (in the pub, in the Belfry, in these pages - infamy is far flung. Ed.) and he retired from the trip and left with the N.W.C.C. back up team. This left me as the sole B.E.C. representative on the trip.

The first sump is a mostly spacious affair with crystal clear vis for the first diver (Anne had that privilege) and zero for the rest!  OHA II consists of a gently ascending walking passage with deep mud giving way to a harder clay or rock floor.  The second sump is perched and very shallow but the roof is festooned with large flakes that demand a cautious approach.  The underwater passage is adequately roomy.  The end of the known cave was reached with little or no incident, and it was rather pleasant to be free of the weight of diving gear.

The 23m shaft had some horribly loose rocks overhanging the drop and these were kicked down with a combination of Websall/Hughes/Whybro brawn.  Rob Harper would have hated this as in most cases the next rock to be loosened was the one sat on for the previous trundle!  Eventually the shaft was declared safe and rigged with a ladder and lifeline, but not before the initially chosen belay had fallen off the wall when tested.  Chris and Rich descended and disappointingly declared that our trundling, although essential, had blocked the way on from the bottom.  They commenced to dig away the offending debris.

Meanwhile, at the head of the pitch, Paul and Kev started to probe the roof.  Eventually, after an exposed and difficult 12m climb, they reached a low bedding passage.  I joined them and used their lifeline to haul up a spare ladder to enable Anne to follow. The low bedding went down dip to a sump and up dip after 15m to a large chamber, with the roof barely visible in one area.   Chris and Rich were called to leave their digging and, when we were all gathered in roughly the same area and a 7m drop from the chamber rigged, a free-for-all race along the large 'Aggie' sized passage beyond began.  The way on was obvious - just keep to the centre of the 10m wide passage and run (or climb) as fast as possible.  Several side passages were noticed but ignored.  The passage runs approximately due south (Rich carried a diving compass) and is a large, phreatic oval, modified in places by blockfall to give large, boulder-floored chambers.  A free climbable 12m pitch led to a sandy squeeze (which may have to be dug out after the winter floods) and a low, muddy area which is possible a perched sump in wetter weather.  The end of the main passage was a descending, boulder floored chamber, ending at its lowest point against a blank wall.  However, through the boulders and seemingly only a few metres away, came the sound of what can only be a large underground watercourse.  A very strong draught accompanied this noise.

Despite fatigue, failing lights and the protests of some (!?) a dig was started following the wall. The boulders here are generally of manageable size and a lot of smaller stones make up a large proportion of the fill. Initially, without tools, the digging progressed well and a 1m deep hole was soon formed.  A further 1m depth could be seen, but proper digging kit will be needed to progress further.

We retreated and made our rather weary way back to the surface.  The sumps on the way out are revolting affairs, with mud getting everywhere, but the original cave seems much shorter.

After a walk back along the dry river Bed and a wash in a pool we were all soon ready for the Loggerheads and some well earned beer.  It had been a fairly exciting ten hour trip.

The next day I had to return to Mendip, but Chris and Paul went back to back to the new find, pushed the side passages and discovered about another 1000m of new passage.  They still left open ends for another day, including a passage that may provide a bypass to the boulder choke and reach the unseen river beneath.

Both OHA sumps, although not free diveable, are perched and as the known system remains completely stream free in the summer months both could be removed by siphoning or baling. The second sump could be bailed very easily, probably taking only a couple of hours but, once completed, would last the complete summer season.  The first sump would present a more involved problem, being longer and deeper, but as a six metre vertical climb is required to reach the sump, which is only approximately 5m deep, the problem is only one of plumbing and is not at all insurmountable.  This sump is, again, totally static and would require only one major attack at the start of the season.

Regretfully the inter-club squabbling and petty personal politics that abound in North Wales caving circles have so far prevented such work being attempted and I can foresee no changes taking place in the near future.

OHA is, without doubt, the most demanding and demanding challenge in North Wales, for approximately 600m of passage has now been found past the first sump, with a potential for much more.  Due to the indifference of the local cavers their role has been merely in the background.

A good survey of OHA I exists but has never been published (for reasons as above) and this is now causing delays in the exploration of this system, for it is possible that a bypass to the first sump may be found from OHA II.  This would open the flood-gates to the potential of a major river cave – the underground River Alyn.  It is time that the North Wales cavers buried the hatchet, settled their differences and started working together so that the full potential of OHA might be realised.


P.S. Further to the B.B. article Pete Appleton (N.W.C.C.) & Co. have siphoned both the sumps in OHA. They failed, however, to enter the new stuff found by the WCC/BEC/CUC; simply because they did not find it.

This does not, however, alter the gist of the latter part of the article about N.W. politics - this action in OHA came from our rather excited babblings in the pub straight after our discovery + a 'Phone call to P. Appleton from Tony Jarratt and NOT as a result of their general settling of inter-club differences.

Chris Milne is in North Wales this weekend (no date on note, Ed.) probing the ends we left.  He should do well.  The underground river Alyn should (!) be found before the winter rains close the cave.

Trev & J-Rat

Alan Coase

It is with regret that we hear of the untimely death of Alan Coase who died of a heart attack recently.  He was a member of the club in the 1960s and many members from that time will have known him well.  Our condolences to his relatives and friends.