You are here:

Water Quality/IRB contributaries and testing


QUESTION: Hello, Steve,

I'm trying to evaluate whether it's worthwhile to revive a residential well.  As I am a recent owner of this and the only person who would know the exact history of it had died before I purchased the property.



Well is finished at 38' (via rotary method) and is about 20 years old.  Calculated GPM when finished was 30 gpm.  It has not been in use for at least 10 years.  At some point around/prior to this time the previous owner (PO) installed a cistern which is being fed by a spring that is nearly 1/2 mile away.  I do not know why such drastic measures were taken, though I do know that because the property was rented that the PO couldn't take his time messing around with the well (as I am now able to do).

The well casing was open to the environment for some time.  Last renter put a roof on the pump house.  Top of casing was never covered after it was abandoned.  Could be a lot of crud in the well: I have a plan to use eduction to evacuate it.

There are signs of iron staining: some rubber seals on shower doors; sediment and traces of slime in toilet tanks.  But these aren't all the prominent because the water source has been from a spring for at least 10 years or so.  Last renter told me that he'd heard that the water was full of iron and was brackish (I believe that was his term).

As far as I can tell there was never ANY filtration on the well: there wasn't anything on the spring either (I have it two-stage filtered and a Sterilight UV sterilizer on it- passes lab tests with flying colors, excellent water, water that I will sorely miss).

To-date testing

I have monitored water visually, noting what I'm sure is IRB (rust colored slime, which lessens after pumping water for a while; white filiment-looking stuff in water).

Lab analysis covering our county's Drinking Water Report returns a PASS for everything.  Sodium shows as 4.1 mg/L.

Based on research I have also had tests for: Turbidity -> 4.01 NTU; Hardness (as Calcium Carbonate) -> 70.3 mg/L; Iron -> 1.97 mg/L; Manganese -> 0.118 mg/L; pH (Hydrogen Ion) -> 7.01

I had meant to ask for an IRB test, but bungled it.  Before I submit a sample for this test I'd like to know what other tests I should probably look to have performed.  Reading all the Q&As from the site suggests that I might also want these tests done: Sulfur (Sulfate the same?); Magnesium; TDS; Chloride; Calcium (or can this be deduced from the Hardness results?).

I need to double-check whether I might be looking at SRB as well.  I think that I'd tried heating up a water sample, but I cannot remember what I'd concluded.  How likely is it that both IRB and SRB could be present?

To-date actions (performed by myself)

Visual monitoring.  Pulling water using a 12v sampling test pump that's only good for about 1 gpm: this is all I have for pulling water from the well.  Output as noted tends to clarify after running for a while (I run for about 1 hr before collecting samples for the lab).

The inside of the casing has a lot of rust flakes, which appear to be only superficial (the integrity of the casing appears fine).  So... I figured I should look to clean the casing.  [After having contacted a manufacturer of casing brushes, and being nearly laughed at, and learning that I, as a mere mortal couldn't purchase one -about $500- I] Started descaling of the casing using a fab'd tool run on the end of a drill: haven't gotten around to finishing because I'm not certain that it's really beneficial.

I keep the top of the casing covered with some plastic when I'm not collecting samples.

Have shocked twice (or maybe three times?) by dumping a gallon of bleach down the casing, running the pump and discharging the output back down the insides of the casing.  This seems to help for a while, though I got a bit distracted with other things and didn't note how long between shockings (I believe that I might have gone one, if not two months between the first two shockings).

Other questions
1) How much can the casing contribute to total iron and IRB? (I did a bit of descaling of the casing, but didn't finish; no idea how much this might have contributed to the iron results); do you know whether there's such a thing as sleeving iron casing with PVC? (and out of pure curiosity, does anyone replace iron casing with PVC in-situ?)

2) Can I put too much bleach in when shocking?  I calculated that I've got about 25 gallons of static water in the casing.  Now that I have done research it appears that I'd only be needing about 3/4 cup of bleach;

3) Should I be looking to shell out money for a real pump, would that even help with cycling water? (I figure 1/2hp, around 5gpm is what I'd look to use for a permanent system)  NOTE: I'll be renting an air compressor (big one) to do a big purge via eduction); will look to shock and cycle as best I can until I have to return the compressor.

4) Would it be worthwhile to have a professional perform a thorough cleaning and shocking, OR, is it likely that, assuming that I could get the IRB under control myself (following more disciplined, multiple shockings), that such action wouldn't really produce meaningful results via a vis long-term control/management of IRB?

I've been told by the well driller that originally drilled the well (info obtained from well logs) that there's another "better" aquifer down around 160' or so.  This same driller, however, also told me that "shocking doesn't work."  I spoke with another well driller (before I purchased the property) and he was very UNprofessional (according to the other driller this guy "only wants to shock; shocking doesn't work").

I really want to get all this right.  And I don't want to be having to spend a lot of time managing a system once it's in place: my current treatment system (on the spring) takes next to nothing to maintain- filters every 3 months (or more), UV bulb once a year).

A new well would run in the $10k range.  I've spec' a rainwater collection system at around $5k (and am confident that I could do one- I met with someone who was on the local county's health board who was operating one that he installed for potable use).

ANSWER: Hi Mark,
I can't really spend a whole lot of time on your project since this is a volunteer site.  What you have asked for is beyond the scope of this service - which is limited to one or two basic questions.
What I can tell you is that, based on what you have written, it would be my suggestion to cap your existing well and start all over again.  Because of the likely contamination of the current well and the overall expense in a quality remediation, it would cost more to clean it up than it would to drill a new one.  With a new one you have the ability to control everything about it and you can ensure the overall integrity of the well, which is something you cant possibly do now.  There are just too many unknowns with the existing well for me to be comfortable with anything short of a total well remediation.
I certainly would not recommend a cistern if there is the possibility of having a nice well.  While it might be slightly cheaper a cistern requires a substantial amount of ongoing time and effort for routine maintenance. There is nothing better, in my opinion, than a underground well water system, especially if it is over 100' deep.  The chances of contamination at those depths are minimal and usually the water is excellent.  It is also very easy to maintain a well water system.
I hope that gives you enough to get a good idea.  I would be happy to help you with additional questions - just not an entire project.  Good luck!
Steve Young
Environmental Engineer

---------- FOLLOW-UP ----------

QUESTION: Steve, thank you for taking time to answer.

Could remediation really be That expensive?  I'm looking at $10k for a new well; and, let's be honest here, NO ONE can guarantee that it would be any better than the existing well.  After shelling out $10 I could still be looking at shelling out $3k for various filtration and purification devices.

I suppose that I could have refrained from question over-load (you note that this site is only good for one or two questions), and I'm sorry if I violated any use guidelines (bothering to even answer my submission was then especially nice of you in this case).

If I have another question available to ask then it is this:

How likely is it (in your experience) that IRB would continue to be a substantial problem (assuming a thorough and successful remediation of the well)?  Again, as you note, it's a shallow well*.

* There are several dug wells out in my area (rural).

ANSWER: Hi Mark,
Remediation can be expensive.  However, if you are certain that the only contaminants are the bacteria and the corrosion products from the casing, then you can probably deal with that for a lot less.  However, if there is a chance that other contaminants got into that well when it wasn't covered then your are gambling with your health.  I misunderstood your question - I thought that it was pretty much a given that the water quality at the deeper level would be really good.
In my opinion if you get a handle on the sulfur bacteria with a good shocking it will not continue to be a problem. Once your system is cleaned, a routine addition of chlorox to the well once a month will control the bacterial populations in most wells unless there are extenuating circumstances.  And I don't see any in your case.  The only way would be if the remediation cleaning is sub-par.
Don't worry about violating any use guidelines - you didn't!  That's kind of my personal rule since I don't have a lot of extra time to work on this site I like to give everyone good answers.  If I spend too much time on one answer then I can't really do the others justice - if you see what I mean.
Anyway, I will be glad to help you in any way that I can.  Feel free to shoot me any more questions - just not an entire project! :-)  Good luck Mark!
Environmental Engineer

---------- FOLLOW-UP ----------

QUESTION: Thanks, Steve, great response!

NOTE: I do NOT know the quality of the water that lies deeper down.  One well driller told me that it was good/better, but this is the same person that told me that shocking doesn't work!

Just to update...

I've got a water sample in the lab for IRB tests: I do NOT detect the presence of SRB, though it's possible it's there it's just not as prevalent as IRB; shocking addresses both, so it's pretty much the same track.  I do not know whether any further tests should be done.  At what point do you stop testing? (that's somewhat of a rhetorical question)

I'm also now in contact with someone who appears to display professional characteristics! (located via referral/reference site mentioned in this site - kudos).

I do not know whether the casing is contributing to any problems, though recent samples did suck up some iron flakes that most likely were dislodged by my initial attempts at cleaning the casing.  The flakes look friendly in comparison to the problems present from the IRB (and dissolved iron) :-)

I totally understand/agree with you on not using this water without ensuring that the well has been cleaned/purged of whatever might be in there from it being open for such extended periods of time (that I think it was).  This is why I had mentioned that I was planning on clearing it myself (using eduction).  This would really be step #2 (after water testing).

A question that I have would be whether it's advisable to apply more meaningful efforts at cleaning the casing walls (light iron scale) before purging.  How much do iron casings contribute to IRB? (I haven't noticed that PVC casings are widely promoted as being beneficial in this regard; technically I could see so, but it couldn't really sell based on this unless it was pretty well known that iron casings played a big part in IRB).

Once the purge out is done I'm figuring that the shocking therapy can take place.

Because so much could be riding on this financially I am wanting to ensure that I am not taken for a ride by anyone I may commission in this endeavor.  As previously noted, one well driller told me outright that shocking doesn't work (this was stated before I'd even purchased the property, before I'd had any research into wells): my research seems to suggest that shocking CAN work for dealing with IRB and SRB, though whether it totally eliminates them or not depends on the individual well.

Hi Mark,
I'm a little confused as to what questions you are specifically asking me so I will say a few things:
1. First of all shocking definitely works - I've been doing it for 30+ years.  I have also used chlorine as a biocide in cooling water systems for about as long and those systems can grow some nasty little bugs, bugs that would make sulfur and iron reducing bacteria look like childs play. The driller that told you that shocking doesn't work was obviously trying to get more drilling business.  Like - shocking doesn't work so you need a new well!
2. When you say you are cleaning the well using eduction what do you mean?  That is a term I'm not familiar with.
3. PVC is the choice of all the reputable well drillers that I work with. The exceptions are very deep wells.  Galvanized casing can contribute considerably to corrosion products being formed in the well water (iron and manganese).  These compounds are food for the IRB's.  Also they cause staining and other problems in your plumbing fixtures.
4. I would suggest that for anyone who you consider hiring to help you with your problem
that you should ask for at least 3 references and then call the references.  Many people just ask for references and when they are supplied, simply assume that's enough. As a result there are many unscrupulous contractors who simply give 3 names - sometimes they are people they haven't even worked with!!

I hope that helps.  If you still have any questions let me know - I will be happy to help you out.
Environmental Engineer

Water Quality

All Answers

Answers by Expert:

Ask Experts


Steve Young


I will answer questions on residential water treatment, i.e. use of softeners, filters, reverse osmosis systems, disinfection, iron and/or sediment removal and other issues facing the homeowner. I have worked extensively with well water systems.


I have worked in the water treatment area for many years as a consultant and as a professional environmental engineer in the private industry sector. I have designed reverse osmosis, deionization, and water softening systems. I have also done work in water quality and stream and river remediation as it relates to the Clean Water Act.

I am currently serving as an Expert for Home Improvement, Travel (New Mexico) and Travel (North Carolina);

BS Environmental Eng.

©2017 All rights reserved.