Break through beyound Ink Sump, Peak Cavern.

[Les W]

You don't actually need to use armoured cable, you could just run twin and earth and keep it out of the way of possible damage.
I believe the BEC pumped the terminal sump of St Cuthberts Swallet, a distance of about 1km (I may be wrong on the distance) using just such cable, a 110v pump and a variac to adjust the voltage at the surface to ensure 110v at the other end.

Using this method will allow a much smaller cable cross sectional area (as you can drop almost half the volts rather than just a small amount) and will be correspondingly cheaper (Cable is priced pretty much by it's copper content). Also an electrician with a trade account will be able to buy it much cheaper (normally).

 

[alastairgott]

I've heard of people using valves and talking of using gas to "airlift" water.

Firstly they say by using carefully placed valves between the sections of pipe and between the pipe and the outside air, you can effectively suck air out of the pipe and therefore prime the system with water without ingress of air.

When running, They say by adding compressed gas into a syphon at certain places speeds up the syphon. This is apparently called an airlift.

i'm pretty sure that jim will want to do his best to find a way in for dry cavers. This could be slightly easier from different places.

Jim, i'm really glad you made the progress this year like you wanted to, heres to you being able to share more success with those that mean the most to you.

 

[alastairgott]

Ps i don't believe you've drank your celebration beer?!?

 

[ah147]

Airlifts don't really work with water. They work with gravel/silt.


Sent from my iPhone using Tapatalk

 

[Pitlamp]

The deepest part of Ink Sump is at -14 m and this point is about 150 m from base.

Although the downstream end of Ink sump has no outflow in drought, there has always been a stream audible within the choke at the far side. This water may well flow into Ink Sump but flow out via an (as yet) undetected outlet before the downstream dive base, thus leaving the dive base static. (This is the same situation as happens in Far Sump, where the downstream end becomes static even though there is always an inflow into the upstream end.)

Therefore the facts (14 m deep, elbow 150 m in, a likely permanent inflow at upstream end) suggest that the idea of draining Ink Sump, to provide any sort of long term caver access, is perhaps somewhat ambitious.

I'd have thought looking for a higher level route might be more successful ultimately. The major choke at the top of the ramp above the Ink Sump dive base has never been hit by a truly serious effort (although the Orpheus [1980s], Keith Bentham [1990s] and other cavers after them have certainly worked the choke). 

In case it helps, there is a description and survey of this area in TSG Journal 17 (2000) pages 8-10.

 

[RichardB1983]

The deepest part of Ink Sump is at -14 m and this point is about 150 m from base.

Although the downstream end of Ink sump has no outflow in drought, there has always been a stream audible within the choke at the far side. This water may well flow into Ink Sump but flow out via an (as yet) undetected outlet before the downstream dive base, thus leaving the dive base static. (This is the same situation as happens in Far Sump, where the downstream end becomes static even though there is always an inflow into the upstream end.)

Therefore the facts (14 m deep, elbow 150 m in, a likely permanent inflow at upstream end) suggest that the idea of draining Ink Sump, to provide any sort of long term caver access, is perhaps somewhat ambitious.

If you could siphon out what is possible in drought conditions, it might reveal the location of the outlet. I wonder if it would be possible to construct a couple of dams to stop water flooding the rest of the sump and channel it towards the outflow? I'm sure it would be overwhelmed in flood, but might work in drought if the location of the inlet & outlet is favourable. 

 

[cooleycr]

If only somebody could actually make Marine Boy's "oxy-gum" then we could all go see for ourselves... :-\

 

[Pitlamp]

The deepest part of Ink Sump is at -14 m and this point is about 150 m from base.

Although the downstream end of Ink sump has no outflow in drought, there has always been a stream audible within the choke at the far side. This water may well flow into Ink Sump but flow out via an (as yet) undetected outlet before the downstream dive base, thus leaving the dive base static. (This is the same situation as happens in Far Sump, where the downstream end becomes static even though there is always an inflow into the upstream end.)

Therefore the facts (14 m deep, elbow 150 m in, a likely permanent inflow at upstream end) suggest that the idea of draining Ink Sump, to provide any sort of long term caver access, is perhaps somewhat ambitious.

If you could siphon out what is possible in drought conditions, it might reveal the location of the outlet. I wonder if it would be possible to construct a couple of dams to stop water flooding the rest of the sump and channel it towards the outflow? I'm sure it would be overwhelmed in flood, but might work in drought if the location of the inlet & outlet is favourable.

If the hypothesised outlet is capable of taking the base level flow then Ink Sump would regularly fall to that level in dry conditions (which, unlike Far Sump, it doesn't). It'd be great to be proved wrong but I think that reliably keeping Ink Sump empty for sustained periods, so non diving cavers could work beyond, would not be easy. Any system attempted MUST work flawlessly; you don't want to find your way back sealed by a sump pool rising malevolently inwards!

Incidentally those figures for the depth and position of the elbow of the sump are probably fairly accurate. Jim told me that their recent radio-location exercise showed the end of Ink Sump is pretty much where our survey showed it to be.

 

[Mike Wood]

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 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?

Just throwing this out there... how much would it cost to drill a small borehole straight down to Dooms Retreat, and dangle the electric cable down it from the surface? 

 

[Pitlamp]

Do you mean financial or environmental cost . . . ?
Is it justified when Doom's Retreat is an easy 20 minute swim away?

The above is at least partly tongue in cheek; to be honest my view is we should let those folk currently involved in the project make decisions about the best way it should be progressed. 

 

[RichardB1983]

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.

Out of interest - is this location close to any known or likely workings on surface? It's meant to be close to Dirtlow Rake isn't it?

 

[pwhole]

The nearest section of Dirtlow Rake is the huge opencut just SW of How Grove mine.

 

[A_Northerner]

Pwhole is this Google Maps overlay freely available? If so would you be able to send me a copy?

 

[pwhole]

No it's not I'm afraid.

 

[Goydenman]

Thanks pwhole....interesting to see where Doom's retreat is in relation to surface

 

[pwhole]

All the cave locations are available as waypoints on the GoogleEarth file available here at the bottom of the page:

http://www.peakdistrictcaving.info/peak-district-caves.htm

 

[nickwilliams]

Just throwing this out there... how much would it cost to drill a small borehole straight down to Dooms Retreat, and dangle the electric cable down it from the surface? 

I don't know what it cost, but this was done to 'prove' the accuracy of the survey before the tunnel into The Battlefield in White Scar was dug, and allowed lengths of household twin and earth cable to be used to power some big lights in the chamber from a generator on the surface.

 

[Mike Wood]

Do you mean financial or environmental cost . . . ?
Is it justified when Doom's Retreat is an easy 20 minute swim away?

The above is at least partly tongue in cheek; to be honest my view is we should let those folk currently involved in the project make decisions about the best way it should be progressed. 

I must admit I was only thinking of the financial cost... just weighing up the price of 3,000m of electrical cable versus the cost of a 2" borehole from surface + maybe 100m of electrical cable...  :-[

 

[MJenkinson]

As an ex-geotech with some contacts in the drilling world, I could try and rustle up a small land rig and a couple of lads to smash out a swift hole!  Unfortunately it won't be big enough to get down. I also suspect it might cheese Jim off if he gets poked in the face by a drill bit suddenly appearing in Doom's Retreat!

 

[pwhole]

Hope Cement had one up there on the other side of the road for a while. They're always interested in big holes