Hey guys!

A friend and i have been trying to clear a blockage from an adit portal in order to gain entry. The blockage comes from backfill dumped down a shaft that connects to the adit.

We have cleared away some material to allow water to escape, but there is a LOT of water behind it. Flooded to within 6 inches of the roof.

I have heard that you should let a mine settle if you clear it. As things weigh less in water we are worried about removing too much water at once. Should this be done or can we go straight in?

Any info would be greatly appreciated

Dave



😎

I would drop the water levels slowly - a tidal wave can lead to unforseen complications - not least of which is that it may draw the unwanted attention of the authorites in your direction.

There is the issue of how far you need to drop water levels. Do you empty the adit completely so that you can enter dry shod or do you lower it just enough so that you have a usable airspace?

The advantage of dropping the water level is that it makes things more pleasant, increases your safety margin, and makes digs further in a bit easier.

The avantage of leaving the entrance partially filled is that it acts as an access control. The Tamar Mining Group dug an adit in the Tamar Valley in 1997 - there were some nice formations inside. In order to protect them the adit was purposefully left squalid (chest deep ochre) with the result that fifteen years on the pretties are still in as good nick as the day we got in.

Obviously circumstances will dictate the approach.

Good luck

Concur with deep water being a very effective disincentive to casual visitors: keep it well over welly depth! (Or better, waist-deep).

Two potential issues with recently desumped (or almost sumped) passages:

(1) There may be dangerously low oxygen levels. The air may improve when external air diffuses inwards, but oxygen can also be stripped by newly-exposed organic matter and minerals. There may - or may not - be elevated carbon monoxidde or dioxide. Be careful - I was part of a group that almost copped it in a freshly drained mine passage in the 1980s: there was no warning other than drowsiness. Advise giving it a few weeks after draining to the desired level and even then checking the air quality - see other threads on aditnow.

(2) The loss of hydrostatic support may result in blocks falling off the roof or off the walls. I've seen this occur as we desumped a mine passage - a couple of circa 1 cwt blocks peeled off with no warning.

Take care!

Bear in mind also that the water itself may be quite nasty, especially if it starts churning about - it may have stood a long, long time, and so you need to be careful where that water goes once you begin letting out, as the Environment Agency wouldn't be too pleased if everything started turning a funny colour a week later. Is there a natural watercourse nearby?

In testiment to how good a deterent deep water is the Fron Boeth slate mine was full of good stuff. I syphoned a couple of thousand gallons out in a couple of hours, enough to drop the water a very critical 2 inches :lol: In this case pipe was 2. inch bore and about 4' head.

You need a weighted filter for the inlet, a length of waterpump suction hose, a 90 degree elbow on the other end and a valve fitted to this for the outlet. Open the valve, Chuck the filter deep in the water, submerge the entire thing being careful to let all the air out of the pipe through the valve. Close the valve under water and haul this end out, get the outlet as low as possible and pointing upwards (elbow stops air feeding back up the pipe). Open the valve and the adit should start to empty. Will work for any size pipe but anything over 2.5" becomes unwieldy. Better off with a couple of 2" ones rather than 1 3" for instance.

http://www.screwfix.com/p/reinforced-suction-delivery-hose-10m-x-2/13658 

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Hey cheers for the replies guys! I,ve not been back to the adit yet, hopefully next week. I was mainly worried about hydrostatic support as Graigfawr mentioned.

I think i have managed to scrounge some 2" hose from a mate who works for Scottish water, so we will use this to syphon off some of the water.

We will probably use a lighter to test the oxygen content, it is a lead mine so hopefully no flammable gasses! It does feel to have a draft in there, but i think this is due to the large amount of water flowing out.

In testiment to how good a deterent deep water is the Fron Boeth slate mine was full of good stuff. I syphoned a couple of thousand gallons out in a couple of hours, enough to drop the water a very critical 2 inches :lol: In this case pipe was 2. inch bore and about 4' head.

You need a weighted filter for the inlet, a length of waterpump suction hose, a 90 degree elbow on the other end and a valve fitted to this for the outlet. Open the valve, Chuck the filter deep in the water, submerge the entire thing being careful to let all the air out of the pipe through the valve. Close the valve under water and haul this end out, get the outlet as low as possible and pointing upwards (elbow stops air feeding back up the pipe). Open the valve and the adit should start to empty. Will work for any size pipe but anything over 2.5" becomes unwieldy. Better off with a couple of 2" ones rather than 1 3" for instance.

http://www.screwfix.com/p/reinforced-suction-delivery-hose-10m-x-2/13658 

You forgot to mention the filter end of the pipe must be kept under water at all times, otherwise syphon sucks air and stops working! 😉

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I would drop the water levels slowly - a tidal wave can lead to unforseen complications - not least of which is that it may draw the unwanted attention of the authorites in your direction.

There is the issue of how far you need to drop water levels. Do you empty the adit completely so that you can enter dry shod or do you lower it just enough so that you have a usable airspace?

The advantage of dropping the water level is that it makes things more pleasant, increases your safety margin, and makes digs further in a bit easier.

The avantage of leaving the entrance partially filled is that it acts as an access control. The Tamar Mining Group dug an adit in the Tamar Valley in 1997 - there were some nice formations inside. In order to protect them the adit was purposefully left squalid (chest deep ochre) with the result that fifteen years on the pretties are still in as good nick as the day we got in.

Obviously circumstances will dictate the approach.

Good luck

this wouldnt be ding dong would it with the damn and waist deep ochre? lol

I would drop the water levels slowly - a tidal wave can lead to unforseen complications - not least of which is that it may draw the unwanted attention of the authorites in your direction.

There is the issue of how far you need to drop water levels. Do you empty the adit completely so that you can enter dry shod or do you lower it just enough so that you have a usable airspace?

The advantage of dropping the water level is that it makes things more pleasant, increases your safety margin, and makes digs further in a bit easier.

The avantage of leaving the entrance partially filled is that it acts as an access control. The Tamar Mining Group dug an adit in the Tamar Valley in 1997 - there were some nice formations inside. In order to protect them the adit was purposefully left squalid (chest deep ochre) with the result that fifteen years on the pretties are still in as good nick as the day we got in.

Obviously circumstances will dictate the approach.

Good luck

this wouldnt be ding dong would it with the damn and waist deep ochre? lol

Wheal Russell

With Tamarmole's permission I could upload a couple of photos to show the entrance with its ochre!

Tin Miner

Cheers for replies, not been back in the mine, as i dont have a car, and my mate has just sold his. Going in on thursday, so will be taking the hose, will take some pics and post them up 🙂

That's pretty much what I was going to suggest Dave, having seen MOLES using the siphon method at Yewthwaite Mine near Keswick. Draining the East Blackcraig adit - I'm assuming it's that one? - during the winter might be a good idea, as the extra outflow from it could be 'expained' by heavy rain.............

Just now I couldn't join-in I'm afraid, as I lost my car in a crash over a week ago, and I'd been forced to keep travel to a minimum before that as I had to raise money to replace it by the end of October so petrol expenses before that would've been a big problem. Once the insurers pay out I can replace it and I'll be able to join you again.

Chris

Hey Chris, hope you are ok.

We are close to getting into the mine, only thing is it might be a tight squeeze over the blockage to stick the other end of the pipe in the water. Cant wait to get in!

Dave

Hey Chris, hope you are ok.

We are close to getting into the mine, only thing is it might be a tight squeeze over the blockage to stick the other end of the pipe in the water. Cant wait to get in!

Dave

Just watch for bad air we came unstuck in a recently opened adit in cwm rheidol and would be very careful in future gas detection if you have got, candle if you haven't or even a cigarrette lighter if the flame sperates from lighter you have a problem

Mike

may be time for a rental on a 4gas and play it safe

Yea i think we will take a lighter down with us. Maybe a bit of a silly question, but would it matter if it was a petrol/gas lighter?

The adit wasn,t totally sealed as it had a lot of water draining from it, and it pushed some of the backfill away. But all of the shafts are sealed on the surface.

Loving the screen name DD, we should get you on our team 😎

Maybe a bit of a silly question, but would it matter if it was a petrol/gas lighter?

No difference. Gas lighter is cheaper though :thumbsup:

Maybe a bit of a silly question, but would it matter if it was a petrol/gas lighter?

No difference. Gas lighter is cheaper though :thumbsup:

Maybe a bit of a silly question, but aren't we in the 21st Century?

Cigarette lighters? Candles? Are you serious?

Flints are more reliable than piezzo in a damp atmosphere.

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With Tamarmole's permission I could upload a couple of photos to show the entrance with its ochre!

Tin Miner

Be my guest