Contaminated fresh water tanks

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JEP

Veteran Member
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Oct 28, 2014
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25
Location
USA
Vessel Make
34' mainship motor yacht
I the misfortune to have a a helper put about 6 ounces of stabil in my fresh water tank 150gal. Thank goodnes they realized the mistake before putting the full amount in. Any ideas on flushing it out.
So far I have over flowed my water tank for about 30-45 min. Now I'm draining my water by faucets. And I an on putting some bleach in when I refill the tanks. Anyone have any input on this
 
Dilution is the best answer.just keep putting in 5-10% of volume empty and do again and again for several times. Check in a clear jar to see if the contaminant floats to top sinks or mixes with the water. If it sinks you might want to put a hose to suck out bottom of tank. If it floats to top maybe a oil sponge type of absorbent on top of tank if you have an inspection port. Then repeated overflow may be good hoping the floating stuff will go out the overflow drain. If miscible with water just the repeated dilution will do. A lot depends on how the stuff reacts (float-sink-mix )to water.
 
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I once read from a book about ships in world war 2 that one tablespoon of oil could contaminate 10,000 gallons of water. Hopefully it will flush out ok.
 
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I once read from a book about ships in world war 2 that one tablespoon of oil could contaminate 10,000 gallons of water. Hopefully it will flush out ok.
If it was I, a couple of tablespoons of Dawn detergent and flush until it doesn't foam anymore. You might also need to add a carbon house filter, which is a good idea anyway.
 
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Why using the plumbing/faucets to rinse when the contamination was isolated to the tank and fillup tube?

Too late now ... now, bleach bath first to dislodge any biosludge that could absorb the contaminants and rinse, then detergent bath, rinse, another detergent bath as needed and rinse, rinse, and repeat as needed. Good luck!
 
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It is a VOC or Volatile Organic Chemical. All approaches listed above will help but I would add aeration as the best form of limiting the continuing potential of contamination. If you have an access hatch remove and once the tank has been flushed several times and emptied place a fan blowing in it. The nature of VOC's is that they have a very low boiling point and will vaporize fairly quickly. The problem arises on whether they will bind with your tank material. If it is a plastic or PVC tank you may have trouble.
The health risks associated with VOC's are multiple and usually develop over a long period of time. I would highly suggest that you contact one of your local water professionals and have a VOC test done prior to consuming any of the water and after you have flushed and aerated. Don't just ask for a water test - specify VOC. Your state EPD lab can do it but there are some guidelines in collecting the samples. Primarily in collecting the sample in an air tight container 50ml with a cap that will seal and NO AIR trapped in the sample. PM me if you have any questions about that.
 
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Stabil is most likely made up of several different VOC's. You can easily find the EPD's MCL on each one listed on the label. MCL is Maximum Contaminant Level. Google VOC and MCL and you may find the info on the net. Once again if taking a sample be sure to do it with a meniscus forming on the sample container to insure no air in container.
 
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I agree with the multiple flushes with dawn and agree with the ventilation of the empty tank between flushes. If you don't have a tank clean-out you can positive ventilate your tank by blowing air down the fill line with one of those high volume air pumps like you use on water toys / inflatable boats some of the air will exit the overflow. I would not reverse a wet/dry vac as the air can be bad from the vacuum. Not the best but better than nothing.
 
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Great idea, I will remember that.
 
I looked up the MSDS on Stabil. It doesn't sound like 6 oz. in 150 gallons of water will kill you. Might make you wish you were dead.


"Ingestion: [FONT=Courier New,Courier New][FONT=Courier New,Courier New]Toxicity is relatively low, there is a risk of aspiration of product into the lungs. On ingestion of large quantities, slight GI discomfort diarrhea, and headache may occur. Small doses may produce irritation and diarrhea."[/FONT][/FONT]
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Here is a link to the MSDS: http://www.americanamb.com/ops/1101MSDS/StabilFuelStabilizer.pdf
 
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It's hard to find good help! :banghead: Just keep flushing and make the guy that did this test the water after each flush. Good Luck!
 
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Thanks to everyone, I have flushed and reflushed and bleached and rebleached and reflushed again, tomorrow comes dawn dish washing liquid. If this doesn't work, oh well, I've been wanting to lose a few pounds. See what happens.
 
Dishwashing detergent? What about something without suds like luandry detergent instead. Good luck.
 
I would contact Stabil customer service. I would ask them for the protocol they recommend. A friend put several gallons of diesel in his water tanks. The first thing he did was disconnect his tank from the rest of the plumbing. He then drained the tank. Refilled and flushed many times. Then used a charcoal filter. All was good.
 
Not uncommon in my industrial experience to see an organic misdirected. Sodium carbonate or baking soda is a good organic neutralizer. Same for caustic soda or sodium hydroxide.
 
Once again, air stripping and/or aeration is the preferred method on water tanks. You would be using its own properties to dissipate the VOC's. In other words, they want to be part of the air-let them.
 
Some idiot (me) put a few quarts of diesel in one of my water tanks last summer. I tried all sorts of concoctions to flush the tanks with no success. After searching online for days I found a thread that gave me the answer. I mixed 2 gallons of bleach and one cup of dish detergent in my empty tank and filled it with water. Then I opened the tank and cleaned out the couple of gallons in the bottom of the tank. After rinsing I repeated the process and rinsed twice with clean water. Next water test was perfect.
 
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Larmex99:

Just wondering what water test was performed and how it was collected.
 
Larmex99:

Just wondering what water test was performed and how it was collected.

In Florida you can get a sample kit from the health department and have them test

in most of the larger counties they do it on site for you
 
Larmex99:

Just wondering what water test was performed and how it was collected.

I keep a potable water test kit onboard that I got from my watermaker supplier. It has proven to be quite accurate and I use it on dockside water sources before I add it to my tanks. So far, so good.

I use First Alert tests and buy them online from Target.
 
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I think that we are dealing with different aspects of water in the tests. Typically the health dept. will test for bacteria - coliforms. Our health dept. here will do those too. In this case V.O.C.'s are the contaminants. I had to go to Continuing Ed. classes for three days to learn the proper technique and requirements for collecting each of the 273 different contaminants that our state tests in public drinking water. The VOC test collection involves a 50ml tube with a special cap that allows, given a meniscus of water above the sample container to enclose the sample without any air. Then it is placed in a cooler filled with ice and must be supplied to the state approved lab within 12 hours. They report back what was found along with the MCL (Maximum Contaminant Level set by EPD). Bact-t tests have 36 hours to get to the lab and don't require the lack of air in the sample. I won't even go into what is required on the Radon and Radnuclie testing.
 

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