Mines

Inspection (Wrysgan and Geironydd) update, March 2017

Inspection (Wrysgan and Geironydd) update, March 2017

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Inspections are going well. Today we looked at Wrysgan and the Geironydd trials.
There was very little of concern in both, however our mine engineer has suggested we monitor the brow of the adit that leads outside on floor 5 of the mine (the wet way out) as there looked to be some blocks that look like they may fall at some point, although there’s no evidence of a fall on the floor. This is the exit directly next to the eased block that fell several years ago (photo attached) directly above the solid ladder, and potentially somewhere groups may gather having scrambled up the ladder.
Also within Geironydd the frequently used trial (opposite the waterfall that drops into a short adit) had several bats in the back of the stope. There is a circular route that follows the back of the stope around several timbers and drops down via a short slide/slab. It may be prudent to avoid that section of mine in the Winter as the bats are hibernating.

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Rhiwbach Update (and gate code change)

Rhiwbach Update (and gate code change)

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Work has continued today to get the steel carried into the mine in place (thanks again to the Go Below staff for the work).

However we could do with some help on Saturday morning (10:30am at the Cwm car park) shifting more stuff into he mine (including a second boat).

Please get in touch if you’re able to help.

Also during the mine inspection week, on Thursday the 30th of March, the gate locks will be replaced with new, and the code changed. Contact whoever you’re working for to get the code.

Gethin

Wrysgan Rock fall

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Sounds like there’s been a small (but worth taking note of!) rock-fall above the traverse on floor 3 of the mine:

Hi Gethin,

Picture attached of a recent rock fall in Wrysgan. Abseil stance at the end of the L3 traverse, after the island!

Obvious missing bits from the roof but I couldn’t see anything hanging….waiting to drop!!

Couple of pieces managed to make it down to L2 at the bottom of the pitch!!

Regards

Jim.image002.jpg

Rhiwbach Anchor Testing Report

Rhiwbach Anchor Testing Report

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On the 18th of March 2016 the majority of the anchors in Rhiwbach mine were inspected and tested. This work was requested and funded by Go Below Underground Adventures Ltd who engaged Pete Knight to undertake the testing.

The anchors were tested to 6kN for 15 seconds using a Hilti HAT-28 anchor tester with a current calibration certificate. All anchors that passed (showed no movement, deformation or rock failure) were marked with a green cable tie. Anchors that were deemed to have failed (moved, deformed or detached from the rock) and could not be removed from the mine were marked with several red cable ties. No failed anchors remain attached to fixed rigging. Unmarked anchors were installed after the 18th March and remain untested.

There are no plans to retest any anchors on a regular basis as it is a concern that the resin bond may be damaged by regular high load testing. No Petzl P38 Longlife anchors were tested in Rhiwbach.

Tyrolean Area

All anchors were tested in this area. One Petzl Collinox anchor was removed from the wall under the test load. It detached with a section of slate that showed a hidden area of quartz weakness. This anchor was not replaced as it was immediately adjacent to another which passed the test.

Pool Traverse in next chamber

The final anchor in the chain appeared to have been hammered into the rock to prevent use. It could not be tested or removed but was tagged as a failure. All remaining anchors passed.

Climb and Traverse to Abseils

All anchors passed.

Waterfall Climb

The lowest of the Collinox anchors had a small amount of spalling under test. It was tested to 10kN as a precaution and passed. This anchor should be checked regularly by users to identify any further rock degradation.

Airshaft

3 Collinox anchors failed in this section of the mine. One was removed completely but the other 2 are awaiting removal/destruction but have been tagged as failures and removed from the rigging.
1 Collinox was removed from the rock along with its resin. The hole appeared to have not been cleaned prior to installation. A second Collinox was removed because the section of rock it was in split apart. The third anchor was another Collinox, which began extracting with its resin. Replacement anchors have been installed already but will not have been tested.

Summary

The testing does not diminish or remove the important requirement for all users to inspect the anchor and overall safety system on each and every use. The nature of the rock and the type of use these anchors receive may mean that an anchor can become suspect or even fail in the future. This can happen without warning and cannot be predicted by this testing. All fixed rigging attached to the tested anchors remains the responsibility of the installing organisation and all users are reminded to inspect for safety prior to each and every use.

Peter Knight 3/5/2016

Rhiwbach

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There is a loose rock high on the right side wall of the rising traverse climb chamber on floor 1 in Rhiwbach.

(as you are looking at the climb towards the window, look high and right half way along the chamber wall to your right)

I have raised a maintenance ticket to have it removed. However, it is very high on the wall, and whilst not very big, will be difficult to remove safely.

I will send another mail out when the work is complete.

Thank you.

Chris Phillips
Operations Manager
Go Below Underground Adventures Ltd.

Wrysgan bolting/cable

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Information for users of Wrysgan mine.

On Monday the 1st Feb myself Jim and Andy paid a visit to do some stabilisation work on the alternative route between floor 1 and 2. There was a rough route up almost immediately inside the first chamber on floor 1. Half way up this rubble slope there was a large step with a very dodgy pack wall. We reduced this to a slope and spent some time stabilising the path and moving it closer to the chamber wall. Being close to the wall, the slope should hold up to downhill traffic better than the original route. It will require some traffic to bed it down so take a little care for the time being.

On Monday the 8th Feb a visit was made by me to the mine to place some new anchors and remove the old cable on floor 3.
2 new Collinox resin anchors were placed on the rising traverse from floor 1 to 2, one near the floor and one near the top. These 2 Collinox bolts split 2 of the longer sections of the traverse and make it slightly less exposed rigging uphill and reduce potential slide distances for clients. To make use of these, pack an extra couple of karabiners or maillons and allow a metre or so of extra rope. All the Goujons in the area were checked and tightened where required.
Up on floor 3, near the dressing sheds entrance, a new Collinox anchor was placed close to an existing one to create a compact and high anchor pair for rigging abseils and lowers. It should also be possible to use the 2 bolts as pull through anchors.

Some of the older, more corroded anchors were cut out in these areas to try to de-clutter the mine. There remains a number of Petzl stainless steel plate hangers attached to regular steel spit sleeves with very corroded bolt heads. These anchors should probably not be trusted and there are nearby resin anchors to use in preference in most cases anyway. It is always best to keep steel or alloy types consistent in sleeve, bolt and hanger anchors in fixed rigging to prevent accelerated corrosion.

The cable on floor 3 was also removed during this piece of work, it now being redundant as the traverse can be rigged bolt to bolt at a higher level.

Any feedback is welcome on the new rigging or guides.

Pete

New anchors in Rhiwbach

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Following the discussions on Friday, I placed 2 new anchors in Rhiwbach today. One midway along the traverse on floor 1 around the deep pool, so if you feel the fixed traverse rope is too slack for your group you could clip a krab to the anchor and raise it.
Another anchor has been placed on the left (as you’re looking up) of the waterfall climb not far above the initial steep section, so you can create a belay (using one of the anchors midway up the manway as well) in the middle (or wherever you choose) of the climb, if you choose to belay groups up the short steep section.
Gethin

Some movement in Rhiwbach

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There’s been a report of a rock fall on floor 3 (there’s a reason that floors not an approved route!) in the chamber above the bore-hole. It’s unlikely to have effected the approved route, however worth remaining vigilant. Please let us know if it’s effected the approved route.

Gethin