Difference in Level at each end of a Sump

[graham]

John, can u enlarge on this? Eg:- What OBA's, where can you get them from? Are they non-toxic?  Where would I get  non fluorescent cotton wool? (Oh, I think someone mentioned tampons above, if so, then cool,  I will buy some and check them with my UV light, lol.)

They'd better be non-toxic 'cos you'll find them in Persil etc.

Would it then fluoresce under a UV light, (guess they would), which I have got. Of course, using a non-visual method would require "pre-test detectors (before the OBA is injected) to see if the anticipated risings are contaminated with fluorescent reagents from other sources." Any info would be gratefully received. Ta.

Aye, the water is adsorbed onto cotton wool and the wool will then fluoresce under UV. So do your whites after a wash, check them out. And that's the problem, all you need is one washing machine discharging somewhere in your catchment & you are stymied. Yes, you can check for background fluorescence beforehand, but that's when the guys in that remote cottage were on holiday and didn't do any washing! I would not trust the method anywhere except wholly deserted uplands, like where Pitlamp lives 

Also, " has the advantage of not requiring laboratory reagents to process the detectors". Tell me more! It might be on the page that Leclused posted so apols if so. Not had chance to read it fully yet.

Regards, Mel.

Think Leclused's links were about dye not OBAs. The advantage of OBAs is that no post-treatment is required, just shine the UV at the cotton wool pads.

To cover a couple of other points:

Lycopodium spores are a terrifically labour intensive method and quite finicky.

The other advantages of using dyes is that you can use multiple dyes (though, as Bograt notes you have to be careful, some of them can be pretty nasty) and using a fluorimeter can pick them up individually from your detectors thus enabling multiple traces to be done at once and it is possible, given the resources, to take a punt at quantitative as well as qualitative tracing.

The one thing to beware of, of course, is that some other bugger, water authority, researcher or whatever, isn't also doing a similar trace somewhere nearby, testing for a leak or something & screwing with your results. This is why it is in your interest (as well as theirs) to clear all your traces with the relevant local water authorities in advance. They should know.

And on the subject of screwing up, don't pollute your own detectors! When dye tracing in Ireland, the UBSS used to have a 'dirty' car which carried dye & whose passengers were responsible for injecting it and a 'clean' car whose passengers were responsible for placing and collecting the detectors. These two teams should be kept apart as much as possible, the stuff cross-contaminates very easily.

 

[Chocolate fireguard]

Also, 4 miles is enough to have a noticeable effect from the curvature of the Earth, though I'm posting this from my bed on my birthday so can't be bothered to calculate it.

Graham, given that you were talking about the depth of cave passages beneath the surface, I don`t understand how the curvature of the Earth can matter at all.

'cos the surface ain't flat and over these distances that not flatness becomes significant.

Let us say, for the sake of argument, that you have a cave which is linear, six miles long and with a sink, a rising and a mid-way entrance all of which are at the same height above sea-level. If that is the case (extreme example, not realistic) then although the three points are the same ASL, they are not in the same plane. Indeed the middle one will be about three feet above the plane of the other two.

So, if you use standard survey software to crunch your survey data - and there are no other errors, inaccuracies or whatever - there will still be a difference between the actual and the calculated positions of the entrances which has to be allowed for.

It seems to me that when a cave passage is surveyed the plane taken as horizontal - given by use of a spirit level - actually curves and the curvature is the same as that of the surface directly above (ignoring topographical features of course).

When you talk about a linear passage do you mean linear as like a tensioned massless string, or linear as shown by a survey? I don`t think these 2 can be the same. If the string in the first case were stretched along the passage in the second case its height above the floor would be much less at the centre than at the ends.

 

[Fulk]

mmilner:

What OBA's, where can you get them from? Are they non-toxic?

OBAs are 'optical brightening agents', which are added to soap powder to make your clothes 'whiter than white'; they don't get your kit any cleaner, what they do is coat the fabric and when exposed to sunlight (or artificial UV) they fluoresce, thus giving the impression of being cleaner and whiter. (This counteracts the tendency of some fabrics to go yellow with age.)

I don't know where to get them and I assume that they must be of low toxicity if they're used in over-the-counter products (washing powder).

But you can see why they might not be much good for water tracing in an area where there are habitations, though I suppose if you are trying to trace a stream away from any houses / farms / whatever they could be used.

Incidentally (a bit off-topic), it has been alleged that that once upon a time some butchers used to sprinkle their meat with (carcinogenic)  rhodamine in order to make it 'redder than red'; yuk!!

 

[martinm]

mmilner:

What OBA's, where can you get them from? Are they non-toxic?

OBAs are 'optical brightening agents', which are added to soap powder to make your clothes 'whiter than white'; they don't get your kit any cleaner, what they do is coat the fabric and when exposed to sunlight (or artificial UV) they fluoresce, thus giving the impression of being cleaner and whiter. (This counteracts the tendency of some fabrics to go yellow with age.)

I don't know where to get them and I assume that they must be of low toxicity if they're used in over-the-counter products (washing powder).

But you can see why they might not be much good for water tracing in an area where there are habitations, though I suppose if you are trying to trace a stream away from any houses / farms / whatever they could be used.

Incidentally (a bit off-topic), it has been alleged that that once upon a time some butchers used to sprinkle their meat with (carcinogenic)  rhodamine in order to make it 'redder than red'; yuk!!

Yuk indeed. I was thinking of getting some Rhodamine B as well as some more Fluoroscein so I could do 2 tests at once.... Might forget the Rhodamine now, don't want to poison an underground watercourse. Hmm, food for thought. Wish John Gunn would answer my emails, he'd be able to advise appropriately....

 

[Fulk]

I was thinking of getting some Rhodamine B as well as some more Fluoroscein so I could do 2 tests at once.

I wonder what colour you would get if you tried that and they mixed underground?

 

[Leclused]

I was thinking of getting some Rhodamine B as well as some more Fluoroscein so I could do 2 tests at once.

I wonder what colour you would get if you tried that and they mixed underground?

When doing multi dye you don't inject both at the same spot. Mostly this is done to test 2 or more streams going presumaby to the same source.

You can then check both colors with the same detectors. And when using a fluometer (spectrometer?) you can see the arrival time, concentration elapsed in time.

In the following link you can see some photos from a dye-test in Belgium. Here we worked with a Hydrologist and his equipment.

http://scavalon.blogspot.be/2010/07/nog-een-kleurproef-en-nog-meer.html

Sorry the tekst in dutch but the photo's tell the story a bit.

 

[Fulk]

When doing multi dye you don't inject both at the same spot.

Yeah, I figured that!!!!! That's why I said what happens if they mix underground ? from two different sinks.

 

[graham]

When doing multi dye you don't inject both at the same spot.

Yeah, I figured that!!!!! That's why I said what happens if they mix underground ? from two different sinks.

Well, they don't react with each other ('cos if they did that, they'd probably react with other stuff in the water & ruin the test anyway) & if you analyse the spectrum using a fluorimeter, you can see the relevant peaks for each dye.

 

[nickwilliams]

It's non-toxic, so best use too much than too little, saves having to redo the test.

Non toxic it may be, but were it to get into a water course supplying any demand for potable water, it's very possible that it could trigger an insurance claim which could seriously f*** up the BCA's PL policy.

Water tracing experiments should only be done with the agreement of the landowner and (especially) the relevant water authority. This won't entirely eliminate the risk of a claim, but will substantially mitigate it.

 

[andybrooks]

It seems to me that when a cave passage is surveyed the plane taken as horizontal - given by use of a spirit level - actually curves and the curvature is the same as that of the surface directly above (ignoring topographical features of course).

This problem is well known in mine surveying, and the curvature becomes greater as you go deeper.  The usual practice is to change the scale factor slightly as a function of depth, which allows the passages at different depths to line up with each other.

 

[martinm]

It's non-toxic, so best use too much than too little, saves having to redo the test.

Non toxic it may be, but were it to get into a water course supplying any demand for potable water, it's very possible that it could trigger an insurance claim which could seriously f*** up the BCA's PL policy.

Water tracing experiments should only be done with the agreement of the landowner and (especially) the relevant water authority. This won't entirely eliminate the risk of a claim, but will substantially mitigate it.

The landowner is the NT who are kept fully informed and I am an NT volunteer too. The EA know about it and are kept informed. Dunno about who the water authority is for the Manifold, but this water tracing has been done over many years with no complaints. Except for one test in the 90's by Pete M that turned the whole river green from Ladyside Wood downstream!

I will check with Paul M of the NT where they get their water supply from first. St. Bertram's Well in the grounds of Ilam Park is I believe fed by percolation water and not affected by Manifold floods which turn the river brown and discoloured. I had to explain to some of the public last June at the Family Archaeological day (happening again this June, weather permitting, at which will I will again be volunteering at) why it was brown around the risings, they thought it was pollution. (A flood pulse a day or two before.) I would suggest that would be much more of a problem than a bit of Fluorescein.

Believe it or not, I do know what I'm doing, have been doing it for years with no problem, but am unfortunately dependent on visual sightings, cos I haven't got a fluoroscope. If you can get one for me to borrow for a few months, then that would be great!

Regards Mel. DCA Conservation Officer.

 

[bograt]

Mel, have you done a full documental search to check you are not replicating work already done?.
I know a lot of Dr Trevor Fords students did hydrology theses in the area, though I am not sure how many have been published, three names come to mind; John Beck, Tony Devoto, and Noel Christopher, there are likely to be others, the area was a favourite of Trevor's.

 

[martinm]

Mel, have you done a full documental search to check you are not replicating work already done?.
I know a lot of Dr Trevor Fords students did hydrology theses in the area, though I am not sure how many have been published, three names come to mind; John Beck, Tony Devoto, and Noel Christopher, there are likely to be others, the area was a favourite of Trevor's.

Terry, I know exactly what has been done and what hasn't. Re:- Dr Trevor Fords students, is one of them Dr G.T. Warwick perchance. I have his thesis. I have also read Jenny Potts tracing reports in the Lyre, which were long range tests between Wetton Mill Sink (which Dr Trevor Ford said would never go anywhere, erm I found and explored Darfar Pot which up to now has 366m of passages and still isn't fully surveyed!) and Waterhouses and Ilam Risings.

Pete Mellors did a mass of testing sometimes assisted by me from the Cauldon Low swallets and Deepdale and others, also Hell Hole Swallet in the mid-Hamps valley which he and I were extending in the 1990's. I have all the documents in my caving folder

I am doing shorter range tests to the middle valley sinks / resurgences. They have never been done before, I can assure you.

I have been caving, digging, exploring, doing conservation work and researching in the area for over 30 years. (Since 1977.) I know what I'm talking about.

Anyway, yet again this is off topic!

Regards, Mel.

 

[bograt]

OK, OK, I'll back off!!, methinks thou do protest too much. I do recall a lecture by Noel Christopher to DCA around 1975 which I found very interesting.

 

[ah147]

Slightly off topic but two very quick questions, for an uninformed mind.

Is there a dye available that would turn a small watercourse into a dirty orange colour?

Is it normal to leave a cup in place to collect it?


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[bograt]

Slightly off topic but two very quick questions, for an uninformed mind.

Is there a dye available that would turn a small watercourse into a dirty orange colour?

Maybe one of the E number food dyes?

Slightly off topic but two very quick questions, for an uninformed mind.

Is it normal to leave a cup in place to collect it?

Not that I know about.

 

[graham]

Slightly off topic but two very quick questions, for an uninformed mind.

Is there a dye available that would turn a small watercourse into a dirty orange colour?

That sounds like water running through an iron deposit

Is it normal to leave a cup in place to collect it?

Qu??

 

[martinm]

Slightly off topic but two very quick questions, for an uninformed mind.

Is there a dye available that would turn a small watercourse into a dirty orange colour?

Is it normal to leave a cup in place to collect it?


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Yes:- Rhodamine WT (orange)

http://onlinelibrary.wiley.com/doi/10.1029/WR013i001p00015/abstract

is an interesting page. There are lots of others if you Google " water tracing dye orange"

That page names various non-toxic different coloured dyes that can be used for water tracing.

If you want to collect a sample in a container it would have to be securely anchored so wouldn't be washed away and/or tipped up so loosing it's contents. It's better to use  activated charcoal detectors if you can, but you need the equipment to process them for results. Or cotton wool you know isn't fluorescent already. (ie:- has an optical brightener in it.) Get a UV light to check it, take baseline measures before deploying.

It's not rocket science but you have to take care and be methodical.

If it's only a short distance, then you may be able to get a visual result. Depends on the amount of water flowing through the system, passage sizes, (can result in excess dilution), etc.

Regards, Mel.

 

[Chocolate fireguard]

It seems to me that when a cave passage is surveyed the plane taken as horizontal - given by use of a spirit level - actually curves and the curvature is the same as that of the surface directly above (ignoring topographical features of course).

This problem is well known in mine surveying, and the curvature becomes greater as you go deeper.  The usual practice is to change the scale factor slightly as a function of depth, which allows the passages at different depths to line up with each other.

So if you have (for simplicity's sake) 2 straight horizontal passages vertically apart, the top one joining the tops of a pair of vertical shafts and the lower one joining the bottoms, the survey would not work on a plan that didn`t take into account the curvature of the horizontal plane?
Presumably if the higher passages are drawn to a scale of, say, 1:1000 the lower ones must be drawn to perhaps 1:999.99 to "stretch" them a bit.
I think I understand, thank you.

 

[ah147]

I ask as in Aggy in one of the drier passages (my memory isn't good enough to describe where) there was a small water flow out the wall. It was all orange. Someone had placed a mug/cup on a wall directly underneath it.

Just wondered if that was ongoing dye tracing.


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