Warning - JH boulder piles choke movement

[Brendan]

On a trip down JH today, we noticed the scaffolded route through the boulder choke below the fixed ladders in JH has moved significantly. The scaffold has dropped and bent, the roof above it now looks very loose, and the floor is covered in loose rock, which is constantly on the move. Some of the larger rocks in the floor move when you stand on them, and the whole area appears very loose.
This has happened in the last 2 weeks, and please take great care in this area.
It needs looking at as collapse here would block the route from JH/Titan into the main Peak/Speedwell system. We had a quick look but it is beyond our capabilities and still very mobile. The route is currently open but movement is ongoing.

Brendan, SUSS

 

[Big Jim]

Didnt notice anything out the ordinary on Monday when me n Soulby went through so its happened since then. Did you de-rig the suss ropes?  If not p'raps someone could pop down for a gander n see what needs doing.  I may be down Mon/Yues next week digging again, but depends as still got eldon dig to go at.

J

 

[Brendan]

SUSS ropes derigged on same trip. Talking to Mike the movement occured between trips 

 

[Big Jim]

Its gerrin worse by sounds of it. More rocks dropping at the weekend. From what I hear, signs are to be put up at Titan / JH entrances to warn folk.  Grayson is probably having a dive through at weekend and going to have a gander to see what score is. Hoping he sorts as really cant be arsed going through colostomy to get to new dig site.

Sounds like the place is best avoided for time being.

J

 

[paul]

From the DCA:

UPDATE 25/04/2010:
Nigel Ball and Dave Shearsmith were at Boulder Piles today and witnessed a boulder approximately 0.5 cubic metre fall from the choke while they were below it in the main passage. They had not been through the choke so it must have been dislodged buy the JH stream which flows down through it. BEWARE!

As a precaution it is advised that you hold off from through trips from Peak until it can be sorted. 

DCA is arranging for a warning notice to be put on JH and a warning should also be at the top of Titan.

 

[Jenny P]

JH/Speedwell Connection Choke Collapse - UPDATE 2/5/2010:

DCA Projects Officer, Martyn Grayson, has inspected the choke this weekend and reports that it appears to have stabilised a little now, though he will be looking at strengthening the scaffolding a.s.a.p.  The problem is being caused by the water running through the choke gradually washing out the mine tailings which have "glued it together" so far.  It is likely that the choke will continue to move in the future but will probably remain negotiable - however, IT NEEDS TREATING WITH EXTREME CARE AND RESPECT!

Jenny Potts,
Hon. Sec. DCA.

 

[DAN]

I have a bit off spare scaff and am prepaired to give a hand if required?

Dan

 

[Rob]

Went for a quick look on Monday. Didn't like having my camera out in all the water so just some quick snaps as we ran through.

View from bottom - This is normally a full body length climb up. Much easier now 

View from underneath - Dave is at the top, level with the bottom of the ladders.

View from the top - Looking back from where Dave was in the above shot (camera now a bit soggy!).

I have say credit to the diggers. Hardly any of the scaffold has moved at all, just the whole world around them!

 

[Pitlamp]

"all the water"?

Has the system become wet again? I thought it was very dry at the moment. (Just curious as it affects plans for a forthcoming project.)

 

[Rob]

Has the system become wet again?

It was wet enough to have a grands worth of camera in my hand as i climbed up through.

But no, it is all very dry at the moment. The first pool you traverse in the JH Cartgate (this one

was a 10m pitch down to the water. 

We syphoned Donatella's Mud Sump, spent about 4 hours the other side, and there was still 3" of airspace on the way out. A very nice suprise

 

[mudmonkey]

For the long term, it strikes me that the best solution may be to do something with the water. Specifically, extend the pipe along the caver route and dump the water somewhere where it can run along a solid floor without shifting the choke around. If you leave a stream running through a choke, it will just keep moving. Apparently there is a tube heading in the right direction from the bottom of the ladder which may suit?

Willing to offer (veggie!) burger-power but no great expertise in stream-plumbing techniques.....

 

[Ralph]

Plans are being made to stabilise the route from JH to Speedwell.
Does anyone have access to a source (cheap!) of any of the following.
Aprox 6" H section girder about 6' lengths - we need four (initially)

Armco barrier (type use on motorway). Initially about 5 6' lengths.

Water pipe (6" diam) - the intention is to reroute the water so it doesn't run through the boulder choke (floor) at the bottom of Leviathon.
RJohnCaveataoldotcom

 

[nickwilliams]

There's lots of water pipe available - will PM the details.

Nick.

 

[Ralph]

We are slowly getting promises of materials, what we need now is manpower.
All offers appreciated
RJohnCaveATaolDOTcom

 

[Pete K]

Should my days off coincide then I'll be happy to help. I could possibly rattle up another one too. Feel free to drop me a message.
Pete

 

[Rob]

Plans are being made to stabilise the route from JH to Speedwell....

A scaffold frame has been installed up the aven above the existing framework. This should prevent much more rock coming down.

An piece of scaffold has also been installed onto the existing framework as an extra precaution.

I'll post some of Twebb's pics on here soon for all those interested enough to see it, but not interested enough to go an have a look for themselves (or just too impatient).

I'll let the DCA advise people officially, but i personally think it all looks OK for now. A degree of care does still need to be taken on the slope down as it's still got a thin spreading of scree on it.

 

[Rob]

Here's a few of Cave_troll's pictures of the trip yesterday:

Some of the sherpas in the VERY dry Speedwell canal.

Fitting the new frame above the old frame.

Looking vertically up the new framework.

Thanks again to all the helpers, especially Nick and Keith for all the scaffold.

 

[biffa]

4 of us went into reroute the water that falls down JH in the pipes so that it does not flow through the boulder choke anymore.  There is now a pipe that connects to the green pipe and goes through the gate and down part of the way with the ladders.  When we left it it was almost dry on the bottom ladder although the position of the pipe might need some tweaking.  We thought the water would run away down into the choke but instead it ponded up and flows down over the rubble slope leaving a wet wallow from the choke to the bottom of the ladders.

Well organised Henry (we had everything we needed and spares for when I threw jubilee clips down the choke).  It was the most fun I've had with water pipe, KY jelly and battery operated tools for some time! 

 

[Big Jim]

Oh so you had fun whilst me mike and ann slogged away at dragging that conveyor belt all the way down from the cart gate and you werent even there to use it when we got there. Gits!

 

[al]

While working at Speedwell today with some of the coffin dodgers, Pete and I went and had a look at the work that's been done at the boulder piles. Excellent job folks! The scaff looks every bit as good as it does in the photos (and you really can look at it now the water's been diverted).

The piping makes the bottom ladder a bit more sporting (it's getting cleaner too!) and as a re-route, it's a really good start, but it would be good to see it continue right through to the Speedwell streamway - not just to keep the crawl dry, but to make sure that there's no more disruption to the tailing/boulder stack.

Well done all concerned!