Question? Just ask us!
Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair
InspectAPedia ® Home
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER ODORS, CAUSE CURE
WATER PUMP REPAIR GUIDE
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PUMP SHORT CYCLING
WATER SOFTENERS & CONDITIONERS
WATER TANK REPAIR PROCEDURES
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WELL FLOW RATE
WELL WATER PRESSURE DIAGNOSIS
WELL YIELD IMPROVEMENT
WINTERIZE A BUILDING
Well test result manipulation: Beginning with this article, this series on well water test result manipulation explains why people might do something that prevents you from obtaining an accurate water potability test, how to detect this bad behavior, and what to do about it. Cheating on drinking water tests is a risk to public health, most likely fraudulent, and water test manipulation may come as a surprise to most folks but it happens all too often. Who would do such a thing, and why? How can you protect yourself against water test manipulating when buying a home? We answer those questions.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
CHEATING ON WATER TESTS - Testing Water for Real Estate Transactions - Water Test Cheating Warnings for Home Buyers and Home Inspectors
Also see Choices of Water Tests & Fees: A Summary of Types of Water Tests, Degrees of Comprehensive Water Testing, Details of Water Test Parameters. and Water Testing Advice based on information from Cornell University of Maryland with extensive edits, text additions, and additional references.
The Shocking Case of the Disappearing Septic Dye
How can we detect dishonest water or septic tests?: These photos and case report illustrate how the septic system test process may actually catch someone's attempt to cheat on a water potability test by shocking the well with bleach right before the inspection. Shocking a well can obscure unsanitary drinking water and it might disguise a septic system that is not working.
At a property inspection we noted that the approach to the home was along a causeway through a swamp - the house sat on a rise of land surrounded by wetlands. With very little dry land around the home, it seemed to me unlikely that the property could possibly have a working well and a working conventional septic system (though special equipment could be installed there was none.) But we were informed that these systems were in good working order.
The two photos above show a similar case in which an old home-made septic tank was located just a few feet from a public lake. You can see our septic test water pouring into the septic tank in the upper right part of the right hand photo.]
Bleach in a Water Supply can Hide Septic Dye in the Septic Tank or at Ground Surfaces
The two photos below are of septic dye on a wet leafy ground surface were adjusted in my lab (we boosted the photo's color saturation) for purpose of illustration, to show how a green septic dye may fade to clear when exposed to bleach in the water supply.
We put in some septic dye: During conduct of my septic loading and dye test we introduced a florescent septic tracer dye into the waste system and turned on the building water supply to load the system. Luckily there was access to the septic tank (which we opined was way too close to the wetlands).
We saw the dye entering the septic tank, but ...: Peering into the septic tank we could see my septic tracer dyed water entering the tank. To my amazement, the dye was disappearing immediately on entering the tank rather than staining that water as well.
Do not lean over the septic tank: It's dangerous to lean over or into a septic tank (it can be fatal) so we didn't look further. We had heard of this exact phenomenon from my (now departed) friend Steve Vermilye who had encountered the same thing, which we dubbed the "shocking case of the disappearing septic dye". Fortunately for the home buyer (and too bad for the water test cheater) we knew what this disappearing septic dye meant.
Owner explains why septic dye disappears: we asked Mrs. owner if there were any problems with the well or septic. Happily she was far more forthcoming than the other parties to the selling end of the transaction. "Well," she said, "we were told by XX [name withheld so as to avoid being sued by a large powerful national group] that there would be no problem if we just poured some Clorox™ into our well early this morning before you got here. We were told to run the water until the smell was gone from our fixtures."
What could we make of this? "Shocking the well" with bleach might indeed temporarily hide a bacterial contamination of the water source - it would never "fix" a real problem if one were present. At this point we didn't know if the water source was contaminated or not. But the large amount of bleach put into the system earlier in the day was resting at such high concentration in the septic tank that it was literally bleaching out my dye as it entered!
When to re-test a well that has been shocked with chlorine, Clorox™ or other disinfectants: This question is explained at" When to re-test a well that has been shocked with chlorine bleach or some other disinfectant". Watch out! Testing too soon or testing water improperly after chlorine or other disinfectants have been in use is likely to give false results.
How much bleach is added to a well or septic tank to manipulate a potability test or a septic loading & dye test?
How much bleach would you need to obscure a septic loading and dye test? Four grams of 12% bleach will remove the coloration of one gram of septic dye in solution according to Tramfloc Inc.
When performing a septic loading and dye test we use a minimum of one tablespoon of septic dye powder - which is about 2/10 of an ounce by weight to dye a 1000 gallon septic tank during a septic dye test. Since an ounce is about 28 grams by weight, this means we're using about 5 grams of powder.
So if my math is correct, 20 grams of 12% bleach would obscure a septic dye test. The cheapest household bleach is about 5.25% in strength. A gallon, or 128 oz, should be more than enough.
As we mention in the list above, people might shock a well for a legitimate reason, as one step in determining if the building piping or well casing have become soiled and contaminated or after actually doing work on the well pump or piping in the well itself.
Shocking a well with bleach will have only a temporary effect in reducing the bacteria level in water if there is a persistent source of contamination in the water supply.
We discuss this water problem diagnosis procedure in detail at Interpreting Drinking Water Test Results and Correcting Unsatisfactory Drinking Water and the details of well shocking with bleach are located there.
Frequently Asked Questions (FAQs)
Questions & answers or comments about manipulated, dishonest, or unreliable well water potability tests - how do you protect against water or septic test dishonesty.
Ask a Question or Enter Search Terms in the InspectApedia search box just below.
Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.