Break through beyound Ink Sump, Peak Cavern.

Following 16 years of continues work the boulder choke in the roof of the Doom?s Retreat Aven beyond Ink sump has finally been breached.  Initially, viewing the passage beyond through a small gap in the boulders, the Team thought that they had found a chamber.  After breaking through it was found to be a large void, the far wall being created by a fallen boulder the size of a small house.  The void, which is called ?Endeavour? is 30 meters long, 3 meters wide and 5 meters high.  It runs East to West with the North wall being solid.  At the Eastern end a steep ramp leads up via a corkscrew climb to a ladder pitch (electron ladder in place) at the head of which several routes lead off.  The routes to the East and the middle route are blind.  The remaining route over a boulder has been enlarged to enable access into a muddy crawl named ?Hippo Heaven?.  Just before the end of Hippo Heaven further engineering work has enabled access to a chest height climb between boulders which opens out into ?Clean Washed Chamber?, a large void measuring 10 meters by 5 meters.  This chamber is thought to be vertically above Endeavour, sharing the same solid North wall.  It is hoped that a narrow void visible in both chambers can be used as a link to move scaffold for further digging works.  At the time of writing no easy way on from Clean Washed Chamber has been found although several routes have been explored.

Radio location work done by Ron Hammond linking Endeavour to the surface has shown that the survey to Doom?s Retreat is very accurate by grid reference but was unable to pinpoint the depth of the chamber because of limited signal strength at long range.

There are a few very promising places throughout the boulder chock for a way on but they all require heavy engineering which is not a problem.  Before any future work is carried out on these leads the team must consolidate the work that has already been undertaken, primarily the enlarging and strengthening of the shaft from Doom?s Retreat to Endeavour. 

The biggest challenge of the project is not the 200-meter dive or the engineering but the logistics of supply.  We have a very long supply line for digging materials and limited time available.  Many thanks must go to the Peak Cavern owners, plus staff past and present for their support as well as all our fellow cavers who have transported the tones of materials in over the years.  It would not have been possible to move all the material needed without your help!
:D :beer:
 

Madness

New member
Well done indeed. Your work helps keep us 'none diggers' with new stuff to explore. We appreciate your efforts.
 

Goydenman

Well-known member
Awesome news from a an area of such incredible potential. May there be continued good team work and more discovery in 2017. From all us at the Black Sheep Diggers
 

Brains

Well-known member
Good effort lads - dont think I will take up diving just yet tho it is more tempting.
Hope the finds continue!  ;)
 

Badlad

Administrator
Staff member
Thanks for posting Jim.  Great news and I hope the really 'big' breakthrough is just beyond the next boulder.

I heard a few figures banded about about how many dives you had done through Ink Sump.  I'm genuinely interested.  What is the correct figure?

(y)
 

The Old Ruminator

Well-known member
Ooo. photos please. These sort of efforts make our digs on Mendip seem tiny by comparison. For us " old un's " a couple of buckets of cement and the odd scaffold tube taken down 45m at Vurley, that we deem as hard work, pales into insignificance compared with this effort. Well done and great to see something really caving significant on the forum . :beer:
 

A_Northerner

Active member
Thanks for this Jim, glad all your work has paid off.

Any chance of bailing Ink Sump so the (relatively) sane amongst us can take a peek?  ;)

If any help is needed (and it sounds like it is) feel free to contact SUSS by Email/Facebook and we'll throw some members your way.
 

ah147

New member
A_Northerner said:
Thanks for this Jim, glad all your work has paid off.

Any chance of bailing Ink Sump so the (relatively) sane amongst us can take a peek?  ;)

If any help is needed (and it sounds like it is) feel free to contact SUSS by Email/Facebook and we'll throw some members your way.

I'd love to see you bail Ink Sump...probably need to siphon :p
 

pwhole

Well-known member
I think Jim has calculated the length of pipe required, as we quite seriously discussed whether this was achievable a while ago, but I seem to remember it was about 100m, which in itself would be a right carry-through! But if such a project were ever seriously mooted, I'd definitely be willing to pitch in, if it was actually going to work.
 

ah147

New member
pwhole said:
I think Jim has calculated the length of pipe required, as we quite seriously discussed whether this was achievable a while ago, but I seem to remember it was about 100m, which in itself would be a right carry-through! But if such a project were ever seriously mooted, I'd definitely be willing to pitch in, if it was actually going to work.

From memory of diving the place...it's about 200m long and 17m deep but I can't remember how far in that is, lets say it hit's its elbow at 100m in for argument. That's 100m of pipe in the sump, plus however much pipe you need to get it to a place lower than that for the siphon to work! I just don't seriously think it's remotely feasible...
 

andrewmcleod

Well-known member
ah147 said:
From memory of diving the place...it's about 200m long and 17m deep but I can't remember how far in that is, lets say it hit's its elbow at 100m in for argument. That's 100m of pipe in the sump, plus however much pipe you need to get it to a place lower than that for the siphon to work! I just don't seriously think it's remotely feasible...

Even theoretically (let alone in practice) you can't siphon more than a depth of 10m or so, or suction pump more than about 10m from the top. At the top of a 10m siphon with (normal) water the water will start to boil/cavitate produce bubbles of gas and breaking the siphon. 1 atmosphere of air pressure is approximately the water pressure due to a 10m column of air pressure. It isn't just that it is air pressure that pushes the water through the siphon, because scientists in 2015 managed to get degassed water to siphon 15m (degassing prevented the bubble formation); at least some of the effect is cohesion (trying to avoid creating surfaces, basically).

So even if you built your enormous siphon it would only suck 7m off the top, at most, before it stopped working. You would need a pump sat in the water (or no more than 10m above the water surface at any point).
 

ah147

New member
andrewmc said:
ah147 said:
From memory of diving the place...it's about 200m long and 17m deep but I can't remember how far in that is, lets say it hit's its elbow at 100m in for argument. That's 100m of pipe in the sump, plus however much pipe you need to get it to a place lower than that for the siphon to work! I just don't seriously think it's remotely feasible...

Even theoretically (let alone in practice) you can't siphon more than a depth of 10m or so, or suction pump more than about 10m from the top. At the top of a 10m siphon with (normal) water the water will start to boil/cavitate produce bubbles of gas and breaking the siphon. 1 atmosphere of air pressure is approximately the water pressure due to a 10m column of air pressure. It isn't just that it is air pressure that pushes the water through the siphon, because scientists in 2015 managed to get degassed water to siphon 15m (degassing prevented the bubble formation); at least some of the effect is cohesion (trying to avoid creating surfaces, basically).

So even if you built your enormous siphon it would only suck 7m off the top, at most, before it stopped working. You would need a pump sat in the water (or no more than 10m above the water surface at any point).

Interesting, but the off-gassing of water is it really that fast? It wouldn't be in humans...I need to research this...halftime of oxygen/nitrogen diffusion into water anyone?


Sent from my iPhone using Tapatalk
 

andrewmcleod

Well-known member
ah147 said:
Interesting, but the off-gassing of water is it really that fast? It wouldn't be in humans...I need to research this...halftime of oxygen/nitrogen diffusion into water anyone?

It's not gases coming out of solution that breaks the siphon, its the water boiling. At the top of a siphon like that you will form a (poor) vacuum, and water will boil. The equilibrium pressure formed from this will be much less than 1 atm I think.

(the thing about the 2015 experiment is a bit of a red herring; degassing the water makes it harder for boiling to start as it becomes harder to form the initial bubbles that let it boil, I think)

I once got to have a play with a thing used to measure the triple point of water. It is basically a glass tube with just water in it, but not enough water to fill the tube so one end is low-pressure water vapour. When you tip the tube over, the water pours down the tube as you would expect but because there isn't air in it to slow it down, it hits the bottom of the tube with a real sharp 'whack', which is fun :)
 

andrewmcleod

Well-known member
I was trying to work out whether you could run what I reckon wouldn't be far off 3km of armoured mains cable down to the Sump, but using this:
https://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html

suggests you need 16mm^2 cable which is pricey even to get 300W at the end. 3km would cost you ?10k from here:
https://www.tlc-direct.co.uk/Main_Index/Cable_Index/Armoured_SWA/index.html

which is a bit unreasonable. But I suspect you could get around this if you really wanted; you would just have to accept quite a bit less than 230V at the far end (if you managed to arrange getting 110V then you can use a standard 110->220V transformer!). If you built a set of step-up and step-down transformers, and didn't mind having a 2kV supply running through the cave :p and found some wire rated for the voltage, you could probably get a nice 13A supply down a fairly small bit of cable... if you could use 1.5mm^2 cable instead (which I reckon you could do even at 240V if you don't mind low voltage at the far end) then it's only ?2000, which is admittedly still a fair whack of cash! But then you could hire out your cable to other clubs; how useful would a 240V supply at the coal face, as it were, be for digs everywhere? :)
 
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