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Blue well water
6

Blue well water

Blue well water

(OP)
There's been one previous thread on this, but it was not dispositive, so I am trying for help.  I live in Piedmont North Carolina, on a well: Unfiltered, untreated.  It's been tested, none of the numbers out of whack, pH not low; but the water, when seen in a white five gallon bucket, has a distinctly blue tint; and the toilets and sink will get a blue ring around the drain and the rim, over time, that nothing, not even muriatic acid, wants to dissolve--I have to scrub it out with lavastone.  I do have copper pipes; the house is 14 years old.  Anyone have a clue?
Beach004

RE: Blue well water

3
Blue or blue-green stains on sinks, baths and porcelain, indicate that there is probably copper in the water supply. Copper is usually from the corrosion of copper plumbing. The amount of copper can be found by sending a water sample to a lab for testing.

From memory, the previous thread was asking about water colored blue, not a blue stain on a fixture.

What is the basis for your comment regarding "none of the numbers out of whack, pH not low"? What are your comparing your water analysis to?

If you want an evaluation, why don't you post the numbers. Numbers are needed for hardness, TDS, alkalinity, and pH.

RE: Blue well water

Looked at the other thread again involving blue well water, and the problem was most likely caused by the water softener.

Water softeners will remove all of the hardness, unless you bypass a portion of the flow and blend the flow back together. If one removes all of the hardness, then the softened water will tend to be more corrosive. The corrosive water will corrode the copper water pipes. So the water softener fixes one problem and creates another.

Copper piping by the way is not very resistant to corrosion.

I recall visiting a town in IL that had so much copper corrosion from the water, that the wastewater treatment plant was having a hard time meeting the discharge limit for copper. Unfortunately two different utilities were involved, a water utility and a wastewater utility. The water utility did not want to spend the money to raise the pH so the wastewater utility was having discharge permit problems.

RE: Blue well water

(OP)
I'm sorry--I didn't have the analysis at hand when I wrote originally; now I do.  Here are the numbers:
Hardness: 22 mg/l
Copper: 0.12 mg/l
Alkalinity: 38mg/l
pH 7.1
TDS I don't have a value for.
The lab indicated no problems with the sample.  As I said, there is no water softener.  My own background is as a chemist, but organic; so I'm out of my depth here.
Hope this will enable one of you to make an informed judgment.
Beach004

RE: Blue well water

Your pH is on the low side and as a result, your water is mildly corrosive. A measure of corrosivity is the Langelier index. There are many free online calculators that can be used to determine the Langelier Index:

http://www.cleanwaterstore.com/technical/water-treatment-calculations/langlier.html

Raising the water pH will decrease the corrosivity of your water.  A pH level of 8-8.5 will probably eliminate the corrosion.

The most common method to raise the pH is to use a chemical feed system and feed a sodium carbonate solution. Sodium carbonate is a mild alkali so that there are no major concerns for handling of the chemical.

http://www.water-research.net/corrosion.htm

Here is an example of a municipality adding sodium carbonate:

http://www.cityofsalem.net/export/departments/spubwork/operations/water_services/cc_installed.htm

http://www.clemson.edu/psapublishing/pages/WATER/WQL5.PDF

In summary, if you really want to correct the problem, investigate the use of a sodium carbonate feed system to raise the water pH to 8-8.5.

RE: Blue well water

(OP)
This suggestion will require some thought.  Since my water is totally untreated now, I would have to add a system from scratch, at a cost to be determined.  Might it be cheaper to replace the copper pipes?  

The copper number seems low, but I feel sure the sample was taken after letting the water run, so that's not a good indicator of what could be in it, when it's stood in the pipes all day or all night, I wouldn't think.  My principal concern is that the corrosion will eat away my pipes entirely, which would certainly be expensive to remedy.

Thank you for the expert advice, bimr!

RE: Blue well water

Not professing any expertise here, but I'm not sure it wouldn't be a bad idea to do some further research, at least before ripping your pipes out of your walls.  While I have not run any aggressivity indices and I would not be surprised if your water is some aggressive from what information you have supplied (and as apaprently suspected from other posts, before you provided the analysis); however, it perhaps would be a shame if good pipes are ripped out of your walls, and even more of a shame if this somehow did not solve the blue/stain etc. problem that apparently started the discussion!  
I did notice there is a phone number listed at the site http://www.copper.org/copperhome/Env_Health/environmentandhealth_drinkingwater.html that could conceivably be a helpful resource (or who could direct you to one).

RE: Blue well water

[btw I am guessing that the blue well water sample you have talked about is not directly from the well, as the subject sort of infers, but instead was drawn from somewhere in the house after traversing some significant length of piping.  Advise if that was not the case -- also, it might be interesting in any case to get a visual or analysis sample from close to the well, if that is possible.

RE: Blue well water

(OP)
Now THAT is an excellent idea!  The sample for analysis was, as you inferred, taken from an outside hose bib, but by then the water had been through a good run of plumbing, at least some of it copper.  But if I recall, the pump has a bib on it, and I could fill up the telltale white plastic five-gallon bucket from it, without the sample having been anywhere but the aquifer.  I'll see about it tonight.  Thanks!

RE: Blue well water

Replacing the copper tubing would tend to be expensive. I would wait until leaks appear.

In many parts of the country, PEX is now accepted in lieu of copper tubing.

RE: Blue well water

(OP)
OK, I took the concrete cap off my well, and inside, as I remembered, was a hose bib; on the threads, significantly (I think), was blue-green stain.  I hooked up a hose, let it run five minutes or so, and then collected a five gallon bucket of water, to compare with an identical bucket obtained from inside the house (1) of water that had stood in my pipes for 8 hours, and (2) from water that had been running for ten minutes or so.  Bottom line is, I cannot see any difference in the color of any of the three samples--they all have a definite though faint blue-green color.

So, I'm about 95% satisfied that the color originates in the ground, whatever it is.  (The only minor unknown I have, is how that well bib works; what triggers the pump to run, when the water has not yet been through the pressure tank, under my house?  Could that water somehow have been up to my house and back rather than straight from the ground?)  Since the analysis doesn't indicate any hazardous materials present, and since my pipes don't leak (yet), unless anyone else has a new line of inquiry, I guess I will declare victory.  Thanks to all,
Beach004

RE: Blue well water

Copper in drinking water can be derived from rock weathering, however the principal sources are the corrosion of brass and copper piping. The taste threshold for copper in drinking water is 2 - 5 mg/l. The US EPA has proposed a maximum contaminant level (MCL) of 1.3 mg/l for copper.

It is possible that the copper is from the raw water, but unlikely.

Here are some sampling techniques:

http://www.maine.gov/dhhs/eng/water/Templates/Rules/LeadCopperSampling-Site.htm

Why don't you get your well water tested for copper?

RE: Blue well water

(OP)
I'm not averse to getting the well water tested for copper, but a question:  When I had my house water tested, two years ago (results above), the tester got the water from an outside hose bib; I was not here, but I assumed he would have let the water run before collecting a sample.  Would I be right or wrong?  And if he did let it run (I will call the agency tomorrow, and see if they have an SOP for sample collection), would the resulting sample not pretty much represent the well water?  If not, then can I get a well-water sample, if, as I did yesterday, I go out to the well and take a sample from the hose bib inside the well housing?  Or should I take two samples, one from an overnight "sit" so to speak, and one from the well?
As a one-time chemist, albeit organic, this is almost fun!
Beach004

RE: Blue well water

Not sure that you should assume anything. One would think that the correct location for sampling is where the water is used (kitchen sink for example), not the hose bib. The hose bib is a dead end and not frequently used, so it would not be a good place to collect a sample. So the fact that the sample collector took his sample from the hose bib would indicate that the sample collector was not knowledgeable about taking samples.

This Nebraska document is very comprehensive:

http://www.ianrpubs.unl.edu/epublic/live/g1360/build/g1360.pdf

Basically it states to run the cold water tap for about 2 minutes until the water sample is cold. That would indicate that the water lines have been flushed out. Then take a sample.

Wait 6 hours, and then take a sample of the water that has been motionless in the pipes.

If you go to all the trouble of sampling, I would take a sample at the well in addition to other sampling locations. As the article states, copper is rarely found to be naturally occuring.

RE: Blue well water

(OP)
Wonderful!  That reference is really valuable.  So, it looks like I'll need to take at least three samples to test for copper.  Am I correct in thinking that "22mg/l hardness as CaCO3" means I have soft water?  And pH = 7.1, combined with that, suggests a somewhat corrosive system, you said.

Next question:  As a (former) chemist, is there a reliable test kit on the market that I could buy and do this testing myself?  It might be less of a hassle than trying to get the Public Health folks to sample and analyze for me--the first time was pretty tedious.  Besides--it could be fun!
Thanks again,
Beach004

RE: Blue well water

Am I correct in thinking that "22mg/l hardness as CaCO3" means I have soft water?  Yes

And pH = 7.1, combined with that, suggests a somewhat corrosive system, you said. Yes

Next question:  As a (former) chemist, is there a reliable test kit on the market that I could buy and do this testing myself?  It might be less of a hassle than trying to get the Public Health folks to sample and analyze for me--the first time was pretty tedious.  Besides--it could be fun!

No, the amount of material that you are testing for very minute which makes testing difficult. It is not something that you can do yourself. The testing is done with a Spectrophotometer.

There are many independent labs, you do not have to go to the health department. Check the phone book.

Here is a water lab:

 http://www.e-watertest.com/water-testing-equipment.html

RE: Blue well water

(OP)
I don't know it enough folks are following this esoteric thread to welcome an interim report, but: I did order a copper testing kit, before bimr wrote me; and today I bought a spa pH kit, and just now measured the pH:  I'm getting a reading below 6.8.  That being the case, I suspect I know the answer, I just don't want to accept it!  Let's see if the copper test confirms it; if so, I'll have to do something to raise the pH (getting back to basics, so to speak).  Oh, well.
Beach004

RE: Blue well water

(OP)
I talked just now to the local health department that did my test, two years ago; the water sample was collected after a five-minute run, so it's ground water.  They confirm that, with the very low alkalinity of my water, even a pH slightly above 7 would still be corrosive.  So I'm looking at neutralizers--and at my bank account!  This looks likely to cost me a thousand bucks, plus periodic maintenance.  I wonder what the economics might be of replacing the copper pipe with PEX, instead?  Anyone?

RE: Blue well water

(OP)
Amazing, my copper-testing kit from National Safety Products, ordered Friday, was here Monday.  The results, in light of other data, are not surprising:  Water in my pipes that has stood overnight was off the scale, >2ppm; water I ran in the kitchen for a couple of minutes was 0.4; and the bathroom shower, after two people showered, was 0.1, right in line with what the Health Dept. got, two years ago on a five minute flow.  
So I'll have to get a neutralizer--replacing copper with PEX would be around $4500, doesn't make sense economically.  Installing the neutralizer doesn't look like a DIY project, not in the crawl space.  Good thing my stocks are doing so well, I can readily afford it...Right!

RE: Blue well water

Noticed your reference to a "neutralizer" and not sure what you are referring to. A neutralizing filter will only raise the pH to about 7. So a neutralizing filter will not make a difference in the corrosion. You need a chemical feeder to add an alkali to raise the pH.

RE: Blue well water

(OP)
Thanks for the correction.  It will take Na2CO3, I'm thinking.  Some sort of renewable set-up, don't know if it has to be backwashed or some such.  If so, that in turn may overload my septic system.  I think I need professional help on this one...

RE: Blue well water

Hello, beach004.

I think that the problem is directly in the water source (the well in this case). Any color in water may be dangerous for healt. Blue colored water can be contaminated by cyanids. Better make a complete lab analysis and if there are still doubts, submit the problem to Enviromental Authorities.

RE: Blue well water

Cyanide has only been observed in groundwater at industrial sites or mining locations. Cyanides are generally not persistent when released to water. The form of cyanide at these polluted sites is typically an iron-cyanide complex since iron is ubiquitous.

The chemistry of cyanide is relatively complex so it is difficult to generalize the fate of cyanide released into the environment.

The absence of iron in groundwater would indicate that cyanide is not present.


http://www.epa.gov/OGWDW/contaminants/dw_contamfs/cyanide.html

RE: Blue well water

(OP)
Thanks.

RE: Blue well water

I have exactly this same problem!  I see neutralizing systems for sale, $800 or so for the tank and backwash control.  Is this a DIY installation, or would I need a plumber to do the hookup?  My neighbors have paid nearly $3000 for an installed similar unit--that seems like a lot for labor, unless I'm missing something.
Tx.
MBMarsh

RE: Blue well water

First off, a neutralizing filter will not do anything for you unless your pH is below 7. The neutralizing filter will barely bring the pH up above 7.

What is needed is a small chemical feed injection system to add sodium carbonate. That will raise the pH. A chemical feed system should cost less than a neutralizing filter.

A neutralizing filter should cost around $500 or so and it should take about an hour for a qualified person to install it. You can do it yourself if you are familiar with standard plumbing techniques such as soldering or crimping PEX.

If you paid $3,000, then you were a victim of an unscrupulous salesman.
 

RE: Blue well water

My pH is 6 or 6.1.  Calcite should be able to fix that, I'm thinking.  But if the carbonate injector would fit in my crawl space beside the pressure tank, it would save me having to put the neutralizer tank in my crowded garage.  Do you have any links to injectors?  It's not something I've heard of before.
MBM

RE: Blue well water

The pump approach is attractive, but access to it would be a problem; I'm going to have to go with the neutralizer.  All the local vendors I have called want at least $2500 to install just a neutralizer, not including a softener.  As bimr writes, there are lots of neutralizers for sale in the $500 range.  I don't feel competent to install one on my own; but if it's as simple (for a plumber) as it sounds, could I just hire a local plumber by the hour and have him hook up what I've bought?  He  would probably have to supply some small parts, cut-offs and such; but that should still be less than the vendors are quoting me.  I think...!
MBM

RE: Blue well water

I am from the Gulf Coast area. Thieves around here will strip a building of copper wire, tubing and pipe. I have heard that you can sell it for money. My point is that maybe you could sell your copper plumbing to help offset the cost of replacing the pipes. You may want to look into this and take that into account when doing a cost analysis.  

RE: Blue well water

Good thing I haven't provided my address! winky smile

I'm going back and forth like a metronome on this topic.  One minute I favor hiring a plumber; the next I think I'll go for the security of a known vendor who will stand behind his work.  I know a good vendor; I don't (yet) know a good plumber.

RE: Blue well water

I'm reluctantly considering another approach: Ripping out the copper and putting in PEX.  I'm on a crawl space, two story house, have one upstairs bathroom that is rarely used.  How horrible a mess will it make to do this?  My wife is not enthusiastic about the notion. What are things to consider?

RE: Blue well water

Raising the ph of the water will slow down further corrosion but will not restore your old pipes. If your existing pipe is already corroded and in poor shape, what options do you have?

PEX is generally less intrusive than rigid pipe and quite easy to install.  It is generally easier and less intrusive for remodeling projects than rigid pipe is.

http://www.ppfahome.org/pex/pubspex.html

RE: Blue well water

A point to be considered, indeed; much depends then, on what shape my pipes are in; I hope to have that looked at shortly.  One halfway measure:  The upstairs bathroom having never been much used, the pipes up there might be in good shape now, and likely to remain that way; I could consider going with PEX for the downstairs, which would of course be easier to access, and let the upstairs go.  If money were no problem...

RE: Blue well water

also consider the potential risk of a water leak occurring upstairs.  The pipes are just as old and just as corroded as they are downstairs.  They will remain under pressure.  If they spring a leak you will flood not only the upstairs but the downstairs as well.   

RE: Blue well water

"Just as old," yes; but I doubt "just as corroded."  No one has ever done much living upstairs, just our kids when they visit.  So the water has mostly just stood in those pipes.

  Once the acid in that water has "eaten" all the copper it can hold, it should no longer be corrosive, I should think, and so there should be less damage. For example, if the water's acid were HCl, then reaction with oxidized copper should produce CuCl or CuCl2; but I could easily be wrong.

RE: Blue well water

The copper is probably in the form of CuHCO3, an insoluble particulate, hence the blue water.

I would agree that it is likely that the corrosion will diminish over time when water is standing in the tubing.
 

RE: Blue well water

the water in all of your pipes has the same corrosion potential and it makes very little difference how often you use the upstairs fixtures. Corrosion of the pipes is caused mainly by the low ph of the water, not by running water through them. Downstairs might be a little better because you flush the sediment out of those pipes more often.

RE: Blue well water

Well, let's see.  if it's CuHCO3 (and I really was curious about that) then it's coming from CO2 dissolving in the water, forming carbonic acid; which then reacts with the copper to form that deposit.  But, as it does so, the acid is removed from that particular "pipe-full" of water.  So, until that pipe is replaced, the water in the pipe no longer has corrosion potential.

But anyway:  The plumber just left; he examined the copper pipes, said they were thinning, but not severely; but he gave me a price for PEX throughout the house that was quite reasonable; so my thinking is, let's go that route, and avoid the tank in the garage with its maintenance, and the increased water hardness, and just get it over with.

RE: Blue well water

Your premise on the decrease in corrosion potential is in agreement with the copper corrosion information stated in AWWA's Water Quality and Treatment.

Note that it also stated in that book that an increase in the free chlorine residual may accelerate copper corrosion.
 

RE: Blue well water

That makes sense, from the (little) chemistry I remember; the chlorine would oxidize the metallic copper, converting it to, I suppose copper oxide; that would then be more susceptible to acid converting it on to copper bicarbonate.  At least, it did in 1961...

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