Chlorine treatment for wells

I was recently contacted by a local banks mortgage officer to do a well test on a vacant foreclosed house for her client as required for a Rural Development loan.
The water test came back positive for coliform bacteria and I included this in my report. I discussed this with the Buyers Realtor who said he runs into this all the time and he would chlorinate the well on Saturday and I could do a retest on Monday. The retest came back negative and the sale has apparently closed as I received a check from the Title company.
I recently ran across an article on Inspectipedia and have attached an excerpt for reference which, basically outlines the Chlorination process which closely follows what the Realtor said he did but it also advises that the retest not be done until after the system has been put back into normal service for several days, not just the 15-20 minutes that I flushed the system before the retest.
Would appreciate some feedback:

  1. Anyone have any similar knowledge or expertise on retest timeframe?
  2. Should I contact the Lender and Buyers Agent with this new information? (I actually never had any contact or information on the Buyer.)

Looking forward to some feedback. I would like to do the right thing while staying in good graces with both the Lender and Agent.

Gary, here is the recommendation from the lab I use.
I actually chlorinate my well on a regular basis. I have high bacteria problem due to my well head being to close to the ground.
The bacteria will build up around the pump and has even burnt it out once. I now have a perforated PVC sleeve with a mesh sock around my pump and everything has been fine since.

Thanks for the reply, that attachment was very informative.
I believe I will send both articles to the Lender (my client) and Buyers Agent and request that they notify the new owner.
Thanks again.

Coliform counts can rise when a property is vacant for long periods and the well is not being used. I would not contact the bank or agent. I would contact the buyer and offer to do a free well test to verify that everything is alright. Tell them it is a one time follow up service you offer as part of your fee. Much better to swallow a well test than upset the apple cart AND swallow a well test or perhaps even more. Lesson learned to not be pressured by anyone when performing a service. It takes as long as it takes.

Your welcome Gary, I’m glad I could help.

Chlorination of the Water Well is not something that I recommend to my clients.

Only the installation of a UV Bacteria Guard is recommended.

Why is that?

In my opinion, chlorinating a well is only masking its problems…

Chlorination of the Well is only temporary.
UV Treatment is a more permanent and proactive form of remediation.

And if you have hard water, you need to install a water softener for the UV treatment to be effective.

Also, keep in mind that the UV light needs to be replaced regularly and is expensive.

What both of you are talking about does not treat the water at the source, correct.
Chlorinating a well kills the bacteria inside the well instead of inside the house.

Chlorination of the Well is only temporary.
UV Treatment is a more permanent and proactive form of remediation.

This is what I’ve experienced as well. When systems are winterized and air is introduced you open the door to having bacteria anywhere in the water suppy system. So chlorinating the well should also include running water to each faucet until you can smell the chlorine…and then the real key is to wait the 12-24 hour period as it takes time for the chlorine to work its magic.:smiley:

Thanks David:
In my case, the Agent did run the water into the interior supply system at each faucet and it sat for the 12-14 hours as you indicated.
The real issue in my case is that I did not advise the client of the potential for this problem to re-occur in the near future and that a re-test should have been suggested or better yet factored into my secondary proposal when I told them of the first failed test.
I am leaning towards following the suggestion of Stephen Stanczyk in his reply and contact the new home owner and offer to provide her with a free re-test after the well system has been reactivated for a few weeks.