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Nant y Mwyn Lead Mine

Graigwen

Active member
It is jointly with Natural Resources Wales, well known for their enthusiasm for underground sites (!).
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royfellows

Well-known member
Nantymmwyn Deep Boat level is the probable area for attention. Its collapsed a short distance in and there is a large depression in the field above. Its possible to get into it via Coaling Shaft next to the council road and opposite ahouse called Erwr Hwch, (from memory so please excuse possible spelling error). However I believe that there is no way on from the shaft, hardly surprising as rubbish has been dumped down it for years. There are a few bits and pieces of underground access at the upper site, but thats it. Bottom line, cant see NRW mucking anything up for us
 

Cantclimbtom

Well-known member
Interesting that there's no mention of Pandora. The trials that were carried out earlier this year sound very similar.
The less internet comments using the "P" word the better. Last thing anyone needs is the goontube brigade discovering that (although a wet adit helps guard it from them). Yes, definitely concerns about heavy metals (was it cadmium?) and nearby Llyn "G"
 

Pete K

Well-known member
The less internet comments using the "P" word the better. Last thing anyone needs is the goontube brigade discovering that (although a wet adit helps guard it from them). Yes, definitely concerns about heavy metals (was it cadmium?) and nearby Llyn "G"
That ship has definitely sailed already.
 

Plwm72

New member
Several years ago I aided CA/ NRW in finding their way around the site looking at various locations. At the time, the project was looking at the "Blow Out Potential" of discharging adits (also at various other mines around Wales) should they ever become blocked.
The Deep and Upper Boat Levels had flow meters installed after the visit.
The Coaling Shaft Roy refers to is covered over with concrete lintels (and is on private land) so no longer offers a way into the Deep Boat Level. Interestingly, a depth test was carried out on the Coaling Shaft while we were there through a small gap in the lintels and was near enough the same as the recorded depth, so maybe the shaft hasn't had as much rubbish dumped down it as previously thought? (I sowed the seed with NRW that if they ever wanted to find out for sure, and had permission from the landowner, to get in touch with me and explorers could check for them! :) ) If rubbish in this shaft did block the Boat Level there is the potential for a large head of water to back up, though if iirc, they didn't think this has happened.
The Deep Boat Level is in a private garden so has no public access.

Over the years I've located approx 25 adits across the site, many not recorded on any plans I've seen with only a few remaining open today (some of these only go a few meters). Only a small fraction of the rumoured 20 miles of levels are accessible.



The Deep Boat Level - (the arched portal can be seen behind the iron pipe. Blocked inside, the majority of discharged water comes from the stream seen to the left of the level.)

IMG_20181025_095029316.jpg


And this is where the majority of the discharged water comes from...
Approx 50m beyond the DBL there is a large pool of water where the water wells up.
It's assumed that it is on the point where the DBL meets solid rock and where the level has collapsed. The flow meter was installed towards the bottom left of the photo.

IMG_20181025_094339504.jpg


The Coaling Shaft -

IMG_20181025_111020287.jpg


Flow meter at the Upper Boat Level -

IMG_20211121_153408194.jpg
 

royfellows

Well-known member
Very interesting, thanks. A few comments:
I was told by several locals that the Coaling Shaft had been descended as the people had been seen going down it. This was many years ago. If a way into the workings had been found, I am sure I would have heard about it. As to the ID of those people, I have no idea.

Upper boat level was dug open some years back by persons known to me. When entered it was found to be blocked at a shaft that can be seen uphill of the entrance.

Captain Arall's grave is to be seen at the Church and at my last visit, indeed some years ago, was still being tended and had fresh flowers.

Many years ago I discovered a level, very wet, that I was able to enter in a full wet suit with a small air space. A level off had many clog prints but a way on was collapsed. I tried digging it without sucess.

At the time of my first visit, which would be about 1987, Footway was still open, but hideously dangerous, there was no way on and I was glad to get out in one piece.
 

FreddoChomp

New member
The less internet comments using the "P" word the better. Last thing anyone needs is the goontube brigade discovering that (although a wet adit helps guard it from them). Yes, definitely concerns about heavy metals (was it cadmium?) and nearby Llyn "G"
Pandora, where is this magical place🤦🏻‍♂️
 

Plwm72

New member
Back on topic...
I'm not surprised someone has descended Coaling Shaft in the past, although I know a few locals, I've never heard of anyone doing this in recent years... (suspect it was late 70's?)

If one visits the church there's a useful display on the mine inside (at least there was earlier this year!).

Your "wet level" Roy is still rather damp! I taped off all the hobnail boot prints several years ago. I too had a go at 'your' dig but didn't get far - it's a lonely, watery place to work on ones own!
What I think is interesting about the section of the level with the boot prints is the size, only about 5' high by 2'6 wide - much smaller than the rest and driven from the opposite direction from the current entrance....

No trace of the Footway Level now...!
 
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