Tankard Shaft Dig

Duncan S

New member
Welcome to the digging log for Tankard Shaft, located near the Hunters Lodge in Mendip.
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How it started...
A group of us were sat in the Queen Vic, Duncan was describing a particularly weird tractor seen at the recent Priddy Implements Sale and failing to get across to the group just how strange everything was about it. One of the customers standing at the bar introduced himself by announcing that it was his tractor we were talking about! Turns out it wasn't a tractor, but is a stationary engine designed for agriculture, and yes it is a very strange beast.
This was Tim, he joined our banter and quickly realised he stumbled on a group of cavers. At some point during the evening he invited us to have a look at a mine shaft that had appeared on his land.
A quick look at MCRA revealed there were no documented mine shafts any where near his description. Slightly intrigued, we decided to go along for a look.

Please note:
At the request of the landowner, Tankard Shaft has controlled access.
Please direct all enquires to Sarah Payne.
 

Duncan S

New member
6th Oct 2105
Sarah Payne, Andy Sparrow, Duncan Simey and Tim Payne

Tim took us to the middle of a field full of cows and heaved open a small metal lid.
Our first impression was pretty much "Whoa, that's not what we expected!".
We were presented with a ginged shaft dropping to depths our caving lamps barely penetrated.
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We donned our caving gear and prepared to SRT into the unknown using a faithful Landy as anchor.
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Andy was first down, and with persistent muttering along the lines of 'loose' and 'don't touch this bit' descended to the bottom.
It's about 30ft.
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The top half of the shaft would be ginged if a considerable chunk of it hadn't already fallen away.
The remaining ginging is hideously unstable with significant slumping on one side, enough to have cracked some of the stones.
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The boulder ruckle opens to a small chamber at the bottom of the shaft with the 'roof' looking sufficiently stable to that the hanging death in the top half of the shaft can be momentarily put out of mind.
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Tim gave us a guided tour of the rest of his land which included a number of interesting looking features which might be interesting to dig at some point in the future.
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The main attraction on the tour was the original site of Tankard Hole. It is very close to Tankard Shaft, hence the name we have given to the shaft.
There is currently nothing to see as the land was bulldozed flat, but Tankard Hole was one of the largest shakeholes on Mendip and was explored to 200ft vertically before being abandoned in the early 1960's due to a combination of access problems and sufficient instability that even seasoned diggers were feeling uncomfortable about attempting to re-open the dig.
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We concluded the day by agreeing it would be worth coming back to clear the bottom of the shaft just to see if anything interesting happened.
 

Duncan S

New member
13th Oct 2015
Sarah Payne, Duncan Simey

First attack on the debris at the bottom of the shaft.
Tim had kindly set up a tripod and pulley mounted over the hole to pull buckets out and a trailer to place the debris in, things were looking surprisingly well organised!
So with slightly revised SRT rigging to try and keep us a little further from the wall of death, Sarah descended and started digging.
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The buckets were heavy and as the rope became increasingly covered in clay conditions gradually turned from being merely unpleasant to downright dangerous.
When we stopped, the pile in the trailer looked impressive, but we hadn't managed to shift all the remains of the lambs disposed down the shaft, had only found a few boulders from the missing ginging and no sign of the original cap.
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However, Sarah was extremely excited as she had cleared a mysterious hole on one side of the shaft.
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Peering into the hole there is a small vertical face of rock that looks like cave wall. We can't tell if it is bedrock or just a large boulder, but it looks promising!
Sarah also found that rocks thrown into the crack below this rock bounced down a fair sized drop.
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With hindsight, we realised that the debris in the trailer stunk badly from the rotting lambs (so did our caving suits), but the air at the bottom of the shaft is fresh.
We also realised the shaft has very little dripping water and is surprisingly dry.
There must be quite a bit of air movement in there!

Emboldened by our discoveries but very squeamish about the risk - it was decision time.
If we wanted to push the dig we would have to make it safe(er) which would be a lot of work.
Abandoning the shaft would be an entirely reasonable action.
Time to call in the experts for their opinions....
 

Duncan S

New member
20th Oct 2015
Tusker, Tim Payne, Sarah Payne, Duncan Simey

Sarah persuaded Tusker to come along and offer his 2p on the shaft and neighbouring Tankard Hole.
The evening was a fascinating insight into Mendip geology and engineering of new digs.
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In short, his opinion was that the shaft is worth digging to see if it goes.
If it doesn't go, then he recommends re-opening Tankard Hole as boulder stabilisation techniques have come on a long way since the early 60's and what proved to be a nightmare dig might now prove viable.

One point Tusker definitely made, was that if we wanted to re-open Tankard Hole then we shouldn't do it in the style of the Templeton dig.
He warned us that Tankard Hole might prove to be double the size of Templeton and if done the same way would be massive engineering challenge and extremely expensive.
To illustrate his point, a few days later he gave the three of us a guided tour of Templeton. The closest I've seen to anything like Templeton is images of the Crossrail access shafts. Mind blowing!
And Tusker thinks Tankard Hole might be a bigger project than Templeton - WOW!!!!!
However, Tusker also gave us lots of recommendations on how we could tackle the challenge should we ever be in the position to be seriously thinking about the project.
 

Duncan S

New member
2nd Dec
Vince Simmonds, Sarah Payne, Duncan Simey, Tim Payne

After a delay caused by various holidays, bad weather and general unease about the scary nature of the project, Sarah persuaded Vince to come and offer his 2p on whether we should continue digging.
Tim had found some old aluminium ladders which once we worked out how insert them into the shaft provided far easier than SRT. Vince whizzed down the shaft and poked around with his crowbar before calling Sarah to join him at the bottom.
Tim and I waited on the surface - and waited even longer. There was much discussion which we could hear snippets drifting up the shaft, but no sign of them reappearing.
We were quite puzzled, but it turned out to be good news!

Vince is calling our mysterious hole a rift and by clearing away a few boulders for better access confirmed there is a sizeable drop which he estimates to be about 5 metres.
The hole is not quite big enough to stick our heads through to have a look, and there are some very scary looking hanging boulders above the rift which will need stabilisation before any work is done.

The other thing Vince mentioned is that the floor of the shaft may not be as substantial as it appears and recommends clipping onto a rope before doing any digging down there.
This confirms Sarah's unease about the weird spongy feeling the floor has.
There is a real risk of the shaft opening up under our feet.

The evening was concluded in the Hunters where we devised a three phase plan of attack.
1) stabilise the shaft by supporting the ginging
2) dig out the bottom of the shaft to make sure it doesn't go anywhere
3) stabilise the roof over the rift so we can start digging

In summary - the dig is definitely worthwhile!
 

Duncan S

New member
9th Dec 2015
Sarah Payne, Tim Payne, Duncan Simey
Assessing the work

First job was to tidy up some large protrusions under the replacement cap which were preventing the ladder from hanging nicely.
Tim attacked them with an angle grinder followed by a mallet and chisel. The ladder is now seated securely and makes getting in and out  of the shaft a pleasure.
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All of us went down the shaft to have a look at what work would need to be performed; this was Tim's first time down the shaft.
Unfortunately, as I was preparing to go down I saw a flash of silver in the shaft followed by several large and expensive sounding thuds. My high-end compact camera had been tucked in my oversuit and had fallen out. This was particularly annoying as this was the first time out with the camera after getting it back from a month away at Fuji HQ being repaired for a problem with the on/off mechanism. I may have sworn.
When I got down to the bottom I found the battery had been ejected because the metal base plate had cracked, the screen has hanging off, and it was covered in mud.
Amazingly, once I cleaned the camera and reassembled it, it powered on and seems to work! But it has dings and scratches all over it and the fit of the case now has gaps everywhere. Genuine astonishment that it is still usable.

We decided the way forwards was an RSJ mounted below the wall of death and for us to build up from the RSJ to support the bottom of the ginging.
I attacked the wall with a trowel looking for likely spots to seat the RSJ and managed to find a solid shelf on the left about 2ft below the ginging, but the right hand side is just a sloping wall of stacked boulders which seem to be all that is holding the entire ginging up; so we can't touch them.
However, a bit  of cunning placement should mean that the RSH will be stable enough to build from.

There was one big puzzle though...
While clearing mud to expose the shelf on the left, I hit a pocket stained with red ochre. Examination of the spoil found a nodule of pure ochre.
As far as we can tell, the nodule is on the inside of the shaft.
If it got there by being dropped by the miners, then it means this isn't just a test shaft but was an active mine.
And that implies there is a heck of a lot more to be discovered under the floor of our shaft!

Tim also spotted a substantial wall built up the wall from the floor opposite the rift.
It looks well enough built to be structural rather than just stacked deads.
Tim has proposed that it might be built over an entrance to a side passage; which seems entirely reasonable.

We are getting very excited about digging the floor of the shaft.
Who knows what we will find!
 

Duncan S

New member
14th Dec 2015
Tim Payne, Sarah Payne, Duncan Simey
Starting work to stabilise the shaft

A cold wet miserable Mendip day, but we decided to go ahead with our plans to start work.
Tim is a genius! I though he was joking about making a fire to keep us warm; he wasn't. I didn't know you could use Pine logs like that; once they got going they provided a serious amount of heat. Next dig we plan to bring a kettle so we can have a hot cuppa to take the chill out of our bones.
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Tim had found an RSJ lying about his farm that was the perfect length, but when he popped down the shaft to check the fit he proposed a new plan.
He'd worked out that starting a few feet lower we could build securely upwards in pure stone and would be a stronger repair than the RSJ.
I headed down the shaft to prepare the wall while Tim went and found some suitable stone.

It took a lot of stone and cement!
The back of the Landy in this shot has one of three loads that were cemented in place.
Tim did the wall building with me popping down occasionally to marvel at what an amazing job Tim achieved using the random assorted bits of stone we passed down to him.
In this shot you can also see Tim cutting a pipe into sections to build into the wall allowing any water between the clay surrounds and the new wall to drain.
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We used several large buckets of cement. Sarah said that the exercise kept her warm in the bitterly cold wind. Meanwhile down the shaft Tim mentioned he was overheating; I'm afraid he didn't get much sympathy.
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The wall has been built high enough that it now touches the botton of the ginging at it's most vulnerable point. It is no longer in danger of imminent collapse - hooray!
Next job is to fill in the remaining gap between the new wall and the ginging. It looks like most of the ginging can be left untouched, but the slumped bit needs cleaning and reinforcing with cement.
Today feels like real progress :)
 

tony from suffolk

Well-known member
Oh goody! I've been patiently waiting fifty-three years for someone to have another go at Tankard, since seeing the depression being filled in and reading the exciting but scary description of the original Tankard Hole in "Caves of Mendip". Jolly good luck to you all folks!  (y)
 

Duncan S

New member
tony from suffolk said:
Oh goody! I've been patiently waiting fifty-three years for someone to have another go at Tankard, since seeing the depression being filled in and reading the exciting but scary description of the original Tankard Hole in "Caves of Mendip". Jolly good luck to you all folks!  (y)
Most people think Tankard Shaft won't connect with Tankard Hole.
We may be able to almost throw a stone between the two, but since the bulldozer landscaping there is part of the field that seems to have sunk less which sits between the two. Hence the shaft probably isn't in the same vertical feature.
This may prove a good thing as the ground under Tankard Hole proved exceptionally unstable. The survey is littered with VDB (Very Dangerous Boulder) and the digging log indicates that the majority of trips had near misses and accidents.
It's intimidating reading given we may be heading for similar terrain.
Only time will tell...

I'm planning on posting something about the original Tankard Hole in the near future.
 

Duncan S

New member
I feel the need to explain why so many people are getting excited about a dig next to Tankard Hole by summarising the available information on Tankard Hole.

The MCRA entry for Tankard Hole says:
http://www.mcra.org.uk/registry/sitedetails.php?id=241
This tantalising site was first entered in 1955 when BEC, SMCC & WCC cavers excavated an extremely dangerous boulder ruckle, 52m deep. Despite the enticement of large open passage it was deemed too dangerous to proceed. The depression was filled with rubble and levelled off in 1970.

There is a detailed history of Tankard Hole in the BEC archives including the survey.
http://bec-cave.org.uk/index.php?option=com_content&view=article&id=548:caving-report-6&catid=58&Itemid=509&lang=en
Despite being fairly scary reading, they do seem to feel that the reputation is not wholly deserved.
First of all a lot has been said about the instability of the cave and its bad reput?ation has been spread largely  by people who have never been in the cave.  Original exploration in a boulder ruckle can never be anything but potentially dangerous and every mishap took place on exploratory visits.  The route to the bottom of the cave, as surveyed, is safe provided that common sense is used.  It is imp?ortant not to wander off the "beaten track" in the same way that it is not advisable to wander around at the head of Ar?te Pitch in St. Cuthbert's Swallet.
I noticed the survey image has the elevation printed on the other side of the scanned paper. A bit of Photoshop magic and I managed to recover it.
http://www.wild-landscapes.co.uk/photos/i-kRPHKKq/0/O/i-kRPHKKq.jpg

How big was the shakehole? Huge!
Here's some photos in the MCRA Flickr archive.
https://www.flickr.com/photos/mendipcaveregistryarchive/5011561127/in/photostream/
https://www.flickr.com/photos/mendipcaveregistryarchive/5012161046/in/photostream/
https://www.flickr.com/photos/mendipcaveregistryarchive/5012157808/in/photostream/

Finally, how many digs have their own song?
http://www.harmonieii.co.uk/caving/tankard.html
The team was clearly bouyant about their chances of a major breakthrough; here's the final verse.
You can keep your Tratmans Temple and your Devil's Elbow too,
And your Mortons Pot with stemples and your Cuthberts entrance queue,
For our Tankards hole is going, going steadily down the dip,
Taking Swildons as a feeder and St. Cuthberts as a drip.

Here's a recording of the Wessex Caving Club making a valiant attempt to sing the song at the Crown in Horton in Ribblesdale around 1962.
http://caving-library.org.uk/audio/audiofiles/WessexCaveClub-1962-01.mp3

If anyone has additional information I'd love to hear from you - cheers!  :beer:
 

Duncan S

New member
Worth adding at this point...
When Tankard Hole was being explored, the shaft was not known about.
The shaft only became visible in the last couple of years when the capping fell in leaving a dangerous hole. The shaft top was reinforced and capped with a lid.
 

David Rose

Active member
Thank you for posting this very interesting report. I look forward to reading m ore. I wish I lived close enough to join your team!
 

The Old Ruminator

Well-known member
Absolutely brilliant Duncan. There is so much scope here for ongoing digging projects. It has been a shame that more photos and reports have not appeared. You may have noticed that mine are a little less factual though I hope to cover all the aspects of Mendip digging. Most folk will know where we are but at the moment we have good reasons not to name the place. Just enjoy the "fun" images and bits about technique. I dont think most diggers worry too much about the potential of their digs. Its a day out with like minded " enthusiasts " and for me my weekly trip to the gym. Oh you will need a nice cosey site hut , patio, flower tubs. Great that you have a supportive landowner.
Oh mind yer fingers. At least the swelling has gone down today.
:clap: :clap: :clap:
 

Duncan S

New member
The Old Ruminator said:
Just enjoy the "fun" images and bits about technique. I dont think most diggers worry too much about the potential of their digs. Its a day out with like minded " enthusiasts " and for me my weekly trip to the gym. Oh you will need a nice cosey site hut , patio, flower tubs. Great that you have a supportive landowner.
Oh mind yer fingers. At least the swelling has gone down today.
I've got admit that I felt daunted by the substantial engineering this dig needed from the outset. We'd still be talking about starting if Tim hadn't been so supportive.
It is a worry that if the boulder ruckle resembles Tankard Hole then we won't ever be in the luxurious position of having a nice safe muddy grovel to play with; we could be straight into scary boulder Jenga. This is my first dig and I'm hoping it will be OK as long as I don't stop and think about it too hard.

Yes, Sarah has joked that we should have a site hut, preferably built over the top of the shaft so we can keep dry and out of the wind. I like the idea of flower tubs; a nice homely touch. Maybe it should be brightly coloured like a beach hut with some patio doors - that would definitely raise eyebrows from people driving along the road into Priddy :)
 

rhychydwr1

Active member
Duncan S said:
The Old Ruminator said:
Just enjoy the "fun" images and bits about technique. I dont think most diggers worry too much about the potential of their digs. Its a day out with like minded " enthusiasts " and for me my weekly trip to the gym. Oh you will need a nice cosey site hut , patio, flower tubs. Great that you have a supportive landowner.
Oh mind yer fingers. At least the swelling has gone down today.
I've got admit that I felt daunted by the substantial engineering this dig needed from the outset. We'd still be talking about starting if Tim hadn't been so supportive.
It is a worry that if the boulder ruckle resembles Tankard Hole then we won't ever be in the luxurious position of having a nice safe muddy grovel to play with; we could be straight into scary boulder Jenga. This is my first dig and I'm hoping it will be OK as long as I don't stop and think about it too hard.

Yes, Sarah has joked that we should have a site hut, preferably built over the top of the shaft so we can keep dry and out of the wind. I like the idea of flower tubs; a nice homely touch. Maybe it should be brightly coloured like a beach hut with some patio doors - that would definitely raise eyebrows from people driving along the road into Priddy :)

Don't forget the TV.

 
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