General Updates

Radon Monitors

Radon Monitors

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Radon monitors have arrived and will be placed over the next few days. Please do get in touch if you’re around and fancy getting out of the sun for a few hours to place them!

Monitors are to be placed in designated sites, below is a list of whats going where. They will be in place for 4 weeks then sent off for analysis. Once they’re back the reports will be added to the mine inspection reports folders online.

If you spot any of the monitors when underground over the next few weeks please do not fiddle with them. They are sealed in plastic bags and should not be opened or moved. May be worth briefing your groups…

Gethin

Radon Tests Sites for North Wales Mines

  • Rhiwbach slate mine (6 test kits)
    1. Ventilation door/Head of incline (Floor H, Head of incline)
    2. Tyrolean start (floor I, Ch3East)
    3. Large Chamber on first floor (Floor H, Ch2East)
    4. Museum on first floor (Floor H, Ch8West)
    5. Museum on floor 4 (Floor G, Ch8West)
    6. Base of waterfall climb (Floor F, Ch1East)
  • Wrysgan (2 tet kits)
  1. Pitch head/Air Shaft between floors 1 & 2
  2. Top of roped climb (Floor 2)

  • Fish Caves (2 test kits)
    1. Head of main pitch
    2. Far end of floor 1 workings
  • Bwlch y Plwm (3 test kits)
    1. Bridge
    2. Crossroads on floor 1
    3. Far end of floor 1, 5th adit West
  • Cwmorthin (5 test kits)
    1. G Floor Chamber Z38
    2. Caban 1934, Floor DE, Ch34
    3. Compressor Chamber, Floor DE
    4. Stripey Vein, far chamber
    5. Top of freefall pitch
  • Cwmorthin Floor 4 (1 test kit)
    1. Wire ladder junction
  • Gaewern (2 test kits)
    1. Top of fixed ladder climb
    2. Top of “hole in floor” pitch

 

Useful images from previous inspections

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Here’s a few images/warnings issued over the years that still stand for some sites. These images have dropped down to the bottom of the news feed on the site so I thought I’d add them again and stick them to the top of the updates feed.

Rhiwbach Brow

Here’s a photo of the brow taken after the cracks were originally painted, this image can be used to compare any changes


Rhiwbach Entrance Adit

Picture of the entrance which has seen some vegetation’s slippage over the Winter of 2015-16

Rhiwbach Top Entrance

Photo following clearing some loose rock at the exit of the mine

22 MineReports2013 Rhiwbach Top Exit Picture

Wrysgan Slab

Route passed the fallen (eased) block between floors 4 & 5 in Wrysgan

WrysganSlab2013

Wrysgan Roof

Section of roof which pealed away in 2014. Photo can be used to compare changes

WrysganRockFall 2014

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.

Inspections for 2016 (important update)

Inspections for 2016 (important update)

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This years round of inspections is nearing its end, having had some very long days out!! Thanks to all who’ve come out to help out and share your thoughts, and particularly Les for managing such a busy schedule!

There has been some changes which anyone visiting either Rhiwbach or Cwmorthin must ensure they are familiar with, more details have been forwarded to the registered email addresses of those who’ve bought into last years reports. 

The full inspection reports will be made available to those buying into the scheme as soon as they’re ready.

Gethin

Damp pitch
Morris
New venue…
Corris
Formations in ByP
Tell tale
Damp pitch in ByP
Wrysgan floor 1 (no go)
New venue…
Tell tail

North Wales Mines Users meeting summary

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Thank you to everyone who came along to the meeting on Friday, it was really valuable to get such a broad range of opinions chatting about the use of the mines in such a positive way.

I’ve sent out a summary of the action points to the mine reports group. If you want a copy get in touch and I’ll send a copy out (I don’t want to publish it online as it lists all attending and has a few email addresses in it)

Gethin

North Wales Mines Users Meeting; 29th January 2016, 10am. Oaklands OEC

North Wales Mines Users Meeting; 29th January 2016, 10am. Oaklands OEC

nwmines

Friday, 29th January, 2016

Oaklands OEC

10am-1pm

Just to confirm we’ll beholding a meeting for those who regularly lead groups underground in the mines of North Wales. The aim of the meeting is to try and discus a range concerns that some users have expressed over the last few months, as well as other topics such as access, bolting, radon and this years round of mine inspections. Can I just highlight the concerns expressed have not been targeted at one user group in particular but broadly!

This is an open meeting to anyone who leads groups underground in North Wales, if you are free please do call in.

Rough Agenda

  • 10am Welcome/Introductions
  • Access
    • Chat from Dave Tyson, representing CAL (Cave Access Ltd) who are now managing access to some of the mines owned by National Resources Wales (previously the Forestry Commission)
  • Recent rockfalls underground
  • Rhiwbach parking
    • Concerns expressed about the number of vehicles parked in Cwm Penmachno
  • Group sizes underground
    • Concerns expressed about the number within individual parties being led underground
  • No-go areas
    • Groups continuing to lunch in large chambers for example
  • Anchors underground
    • Results of the BCA supported testing of anchors in slate; should we have a preferred anchor?
    • Funding of anchors
    • Future placements
      • Level 1 traverse on floor 1 in Rhiwbach
      • Steep step in Wrysgan
      • Others?
    • Radon testing this year
    • Mine Inspections for this year (programmed for 11th-15th of April
      • Any additional sites people would like to have inspected & are people available to accompany Les
    • Do we need a more formal users group or an annual users meeting such as this one
      • Look at what’s being done in the Peak District
    • AOB

I’d hope we could rattle through this lot in a few hours, hope you can make it. Directions to Oaklands can be found here: http://oaklands-centre.co.uk/index.php/contact-us/how-to-find-us/

Gethin

12 January 2016