This years inspection reports are now available, however will only be added to providers Google Drive once payment has been received.
For any new providers interested in buying into the reports for this year, the cost of the reports alone are £135, with an additional £25 if you wish to lead groups in Rhiwbach (to cover the cost of parking at the base of the mine, 2 vehicles only please) and replacement locks etc.
This years inspections will take place next week (starting the 16th March) with the programme as follows:
Limited places are available for those keen to accompany the engineer and see what it’s all about! Get in touch if you’re keen
Gethin
A brief write up following last weeks meeting has been circulated to the email addresses for those registered to receive updates on the mines. If you’d like a read bug whoever you’re working for!!
Some key points:
Gethin
The BAs in Rhiwbach were checked today with all passing. Each BA was visually inspected for any damage or lack of function and a selection float tested.
The float test took place in the mine, it would be good to get feedback from users on how quickly they dry should we need to do testing outside in the future. Testing in the mine was quick and easy, and would be even easier in the future as a suitable weight and tether are now in hidden behind the boulders in the boating chamber.
Sheet within the mine’s been updated and a copy here. This sheet may change depending on the outcome of this years users meeting with regards the frequently of inspections.
Gethin
Monday 10th of February 2020
Oaklands OEC
10am-1pm
Following previous years gatherings, we’ve arranged another opportunity for those working within the mines to get together, discuss any hot topics, concerns and find out about on-going projects and issues.
Details are also available here: www.northwalesmines.worpress.com
Rough Agenda
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
2nd February 2020
We’ve had a report today that both the rope fixed to help escape the mine should the entrance flood has been reported to be seriously damaged, and anchors supporting the rope suspect.
If you’re likely to be using the mine in the near future it may be worth considering checking the anchors and replacing the fixed rope.
Anchor testing in Rhiwbach, Bwlch y Plwm, Wrysgan and Fish Caves has now been completed (to be fair Pete finished off Rhiwbach and Bwlch y Plwm over the Summer!)
Anchors within the blue routes were visually inspected, and where appropriate pull tested with a Hydrawjaw test rig up to 6kN for 15sec. To pass the test the anchor needs to hold the load for that period without fluctuating.
All anchors that passed both the visual (i.e. recognisable, no signs of corruption, not deformed, no movement) and pull test will have a green cable tie fixed to them, any that failed (but we’ve not been able to extract) will have a red cable tie. Anchors with no cable ties may not have been tested as it wasn’t possible to fit the test rig over the anchor.
Rigging plans with all the tested anchors are available here, with the exception of Wrysgan which just needs double checking, all will be added to the Mine Inspection Reports folders available through Google Docs.
Several anchors failed during the tests (see video).
In several cases old 12mm SPIT type anchors (found in Wrysgan) pulled at relatively low loads. These all showed signs of corrosion. There are several Petzl long-life (see photo) anchors in Bwlch y Plwm that were not tested, if using these you do so at your own risk. Any expansion anchor to be tested really needs to have the anchor plate removed and the pull device attached directly to the anchoring component. This isn’t possible with the Petzl long-lifes. 
Notably several anchors in Fish Caves failed, and frustratingly it was not possible to remove them. The failure mechanism looks to have been a resin/rock bond failure which suggests the holes were more cleaned throughly before placing the resin. The failed anchors are all on the second pitch in Fish Caves and so requires a slightly different approach to rigging (see rigging diagram). I’m afraid this is going to persecute the short!
Fish Caves is rigged predominantly with DMM anchors. These flex when the tested so it’s not unusual to see the resin around the head of the anchor crack (see the image of a passed anchor below). Do not be alarmed by this if using these anchors. However as will all anchors ultimately the user must make a decision if they feel it’s safe to use. Before each use check;
Please report any defective anchors through the mines inspections email account, through facebook or direct here:
