North Wales Mine ExplorationLatest update April 30, 2015 Started on August 12, 2014
Just a quick update, ROV #1511 "Jemima puddle-duck" Survived her first plunge underground!
Plus points - No leaks.
Cons - Tether doesn't seem ideal for mines, kept getting trapped under slates and we were scared of tugging too hard on the tether for fear of snapping the cable. We are now looking at new tethers and the possibility of adding a system to be able to switch out tethers as we see fit.
More pics and videos to follow soon!
Well, it's all a waiting game now! Many thanks to the Moore Foundation for the funding and of course OpenROV for sending us an ROV.
Will be keeping everyone updated as to when it arrives and the process of assembly.
In the meantime I have been keeping busy by doing a little wandering around some of our surface quarries.
Dinorwic, the second largest slate quarrying operation in Wales, started around the 1780s and carried on to 1969. Many artifacts of the industrial past remain including the old quarrymans canteen or "caban" still with remains of coats on the pegs and shoes, just waiting for the next shift! In the 70s a hydro power station was constructed deep within the mountain to provide extra peak power. An incredible place to visit and well worth a look if you happen to end up in this part of Wales, the old workshops have been preserved as a free museum to the slate heritage of Wales.
As well as flooded underground workings there are many flooded quarries, Amongst one of the biggest and deepest is Dorothea at its deepest over 100 meters. A notorious place for divers having become known as "The incident pit" due to the many divers who have lost their lives here, despite this it is still a very popular place for divers. Dorothea opened in the 1820's and quarrying continued up until 1970 when the pumps were turned off and water began to fill the quarry leaving many buildings and various pieces of equipment in place. We hope to be able to see some of the lesser seen parts further down.
There are also various other pits around Dorothea that are flooded and could hold potential interesting quarrying artifacts.
Artifacts are not always industrial in nature. If you look underneath a slate in a nice dry corner you might just find some remains from the miners. I always wonder about who hid these under a slate 80+ years ago, was he just having a small moment to himself and trying to forget he's hundreds of feet underground? Was he with his mate having a rest from a hard days quarrying? Was he just sneaking a quick break from the management? Did he end up fighting in the war? Did he survive that? I'll never know, but its nice to imagine, guess I'm an old romantic for this kind of thing.
Not far from the connection between Cwmorthin and Oakeley slate quarries lies chamber 34 incline winder. Built in 1934 originally used as a dual winder but reduced to a single, was powered by an electric motor. The speed was controlled by using a brine bath and the voltage/speed altered depending how deep the elements were immersed. Oakeley was at one point the largest underground working in the world with an estimated 50 miles of underground track. Underground operations ceased in the 70s and open casting continued until 2010.
We are hoping we can find similar things in flooded sections of mines.
Oakeley chamber 34 incline, connected together floors DE to I and was driven around 1934. Floor H was once de-watered when the neighboring quarry was pumping out the opencast pit but nothing is known of what lies beyond on floor I. With an open ROV we could discover what lies beyond!
Another example of a North Wales slate mine with flooded lower workings. The pumps were finally switched off here in 1999 allowing water to rise slowly over the next decade or so. It now appears to have reached a stable level as gauged against the steps of a "manway".
The floors here are around 70ft apart with at least 2 levels below water.
Although this mine was worked as late as the 1990s, earlier sections had long been abandoned, often with ancient artifacts left in place. These may take the form of miners' personal effects such as clay pipes, lamps and tools or mining infrastructure like rail lines, trucks and bridges.
An openROV would allow us to get beyond the tantalising glimpses we're currently afforded of this lost world.
But time is of the essence. Modern day untopping work is threatening access to this particular mine with some unique sections already lost.
In North East Wales, a substantial, underground lake was discovered by miners in 1931. Flooded to hundreds of feet below sea-level, its true depth has long been the subject of speculation. Several thousand gallons of water a minute run through, draining to sea along miles of man-made tunnel.
This crystal clear water provides excellent visibility but diving is precluded by the long and arduous access route.
Exploration by ROV appears the obvious solution and would provide an invaluable insight into this fascinating natural cave system.
Many of the mines in North Wales have flooded levels, inclines, shafts and stopes. An open ROV would open up our world to what we would be able to see. We have caught glimpses of equipment in flooded sections using high powered torches but these can only cut through so much and leaves us wishing to see if more lays further beyond.
I will be uploading various photos of mines over the coming weeks and updating everyone on what we have been getting up to, a group of us usually meets up every Thursday night for an evening of mine exploring so expect updates from us at various points!
The photo included in this post is taken in Cwmorthin slate quarry. Slate extraction started in 1810, underground quarrying started around 1861 and continued to 1970, where much smaller scale quarrying took place until the 90s when the quarry finally shut. It remains a fantastic example of Victorian industrialism
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