Rhiwbach

Rhiwbach Update (and gate code change)

Rhiwbach Update (and gate code change)

nwmines

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

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

nwmines

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.

New anchors in Rhiwbach

nwmines

 

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

nwmines

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

Rhiwbach Entrance

nwmines

Hi All,

As I’m sure everyone is aware there was a small(ish) land slide at the entrance to Rhiwbach a few weeks ago. Last week I managed a good look, and as well as some topsoil and smallish gravel sliding out of the bank on the left of the entrance there also appears to have been some movement/clearing off of surface vegetation and rocks from the entrance. There’s some photos of the entrance here:
One thing to keep an eye on is a large block above and left of the entrance which has got some cracks running along the bottom, side and back of it. It’s probably worth keeping an eye on, and, as with all entrances/exits, best to gather groups away from the entrance and move people through quickly.
Worth being particularly vigilant given the rain over the last few days/weeks (feels like months…) Please do let us know if anything changes in the mines.
Last week we had to inflate the front of the boat, if you find it the same could you let us know; it may need a repair. When the water levels go up significantly the boats been known to wander off down the entrance adit, so it may be worth tying it up at the far end of the boating pool if you’re one of the last groups in the mine.
Gethin

Rhiwbach Entrance

nwmines

Hi all,

Just had a message that the entrance to Rhiwbach had a bit of a mud and rock slide in yesterday’s damp spell! Who knows what other mischief the water may have got up to yesterday. Would be worth highlighting to staff the need to move swiftly through the entrance/exits of the mines as well as being extra vigilant when underground, particularly around the brows of cross-cuts or areas highlighted within the inspection reports as needing monitoring.

We should also remind folk to avoid spending to much time in large chambers (as highlighted in the last few mine inspection reports) as it’s difficult to properly inspect the roofs.

All the best

Gethin Thomas
www.train4underground.co.uk

Rhiwbach rockfall

nwmines

Comment: Rhiwbach Fall.
Yesterday (19th July 2015) our staff reported a fallen block in the ‘Caban’ chamber of the drainage level in Rhiwbach slate mine. The fall occurred in the rear of the chamber, an area not normally visited by groups or staff.  If you were to stand with the caban on your immediate right looking inbye, this is the area of the chamber directly in front of you. The staff member was in the chamber when the fall occurred, and based on his experience as a slate quarryman and quarry blaster, he estimated the fall to be in the region of 1 to 2 tons.  We have had the chamber roof inspected by a CIC holder today, who has reported back to us that the roof and chamber walls in the immediate area used by staff going to get the boat are not affected by this fall. Misty conditions due to the wet weather today did not allow for a totally clear view of the rearmost reaches of the chamber, so at this point we have been unable to establish the exact location and extent of the fall.  Another inspection will be done tomorrow, hopefully with better visibility in the chamber.  I am aware that some users take their groups to have lunch near the caban in this chamber, and would urge all users to exercise extreme caution in this area.  We will inspect this chamber and the surrounding areas on a daily basis for the next few weeks and report any updates or further changes here.
Chris Phillips Operations Manager, Go Below Underground Adventures Ltd.