Oil in fresh water tank help

[hirondeller]

With regard to post #45 there may be an advantage to unscented simple green (SG) since this is drinking water? The fragrance is a 'citrus oil' scent? I did assume that an extensive rinse would take place and should remove the scent. I note that the SG Grainger products are ~2.5X more expensive than at home depot ($10.00 gal); home depot also carries a SG 'commercial version'.



All of the simple green products seem to be 'low foaming cleaners' but the foam gun still creates a clinging expanding foam that might help in stripping oil from any surface.


I had a dump truck cover our car with an oily puddle during a rainstorm, after the water dried, dust stuck to the oil; what an ungodly mess. I foamed the car with simple green, waited ~15min, then rinsed, all of the oil was gone, I also had to re-wax the car! SG stripped that off too!



I forgot to say above that a short wait time, to let the SG foam work, might be very helpful.

[Captn_Black]

Originally Posted by Capt. Strapfoot

I got a significant amount of oil in my water tank">fresh water tank. Is there an additive I can put in to help me flush the tank clean enough to drink from it

If it is stainless steel you can clean it. I inherited a jerry can with my ship that had oil in it, I wanted to use it for water. After much cleaning it was still not potable. So I used it only for washing water. Now, 4 years later, and after being essentially rinsed with fresh water for all that time, it is finally clean. Maybe degreaser? But that might just create more problems so I didn't try it.

[Captn_Black]

Originally Posted by Lepke

In the military, officer like thinking got us several 55 gallon drums for fresh water that previously held diesel. Several cycles of use and then recleaning went on with the diesel taste never leaving.
Possibly a strong detergent, allowed to sit, might remove enough oil so a good filter can remove the oil taste.

Can confirm, no it won't

[Steve DAntonio]

I've been down this path with diesel in water tanks. A hot water pressure washer will work if you can get it into every baffled chamber. Barring that, in one case, and where the tank was plastic, after cleaning multiple times there remained a slight odor, as another member noted, we installed a charcoal filter and it removed all taste and odor issues.

[Capn Jimbo]

This is a serious problem. Oil is a VOC (volatile organic compound) and not at all healthy to ingest. I'm confident that few of us would like to chance regular ingestion of even trace amounts over time. No method of cleaning suggested is 100% - not to mention the cleaners themselves will leave some residue.

I daresay that none of us would be comfortable drinking out of an old gas can no matter how many times you "cleaned" it. The problem here is that you don't want to replace the tank.


Here's my take:

1. First and foremost, the engine installers failed badly. They may be held responsible for a tank that will not be the same for years, if ever.

2. This may an insurance claim as well.

3. No amount of cleaning will restore your tank to it's former water only usage. Period.

4. If you disagree, it is possible and affordable to have your water tested for VOC's, et al. You should take a sample now to document the fail, then another after your likely failed attempts to completely clean the tank to demonstrate the problem and/or to determine what you'll be ingesting for the next few years.

5. Ordinary filtration is a make shift response, even multi-stage filters with frequent filter replacements. Reverse osmosis is better, but expensive. In both cases you'd be attempting to treat the symptoms, not the cause - a ruined tank.

Finally - a question: just why do you (OP) consider the proper solution: replacement of the tank - why do you consider this a HUGE job? Of course it's a job that no one wants to do, but tank replacement often is really not all that hard. Is the tank baffled? If not an insertable bladder might be yet another solution.

[kayakerChuck]

I just asked my smarter half what to do. Her unequivocal answer is to replace the tank. There is nothing she is aware of that will remove the oil, and the additives in the oil, to a point she would be comfortable drinking drinking water from that tank.

(My smarter half is a chemistry professor for the University of Michigan.)

[hirondeller]

There is risk in all things, and drinking water containing 'trace' chemicals is one of them. I actually do not know of a 'completely uncontaminated' water supply. In some US cities tap water has a recurring problem with trace chloroform (a known carcinogen) due to chlorination of a 'surface water supply' that contains organic compounds.



Truly, it is "the dose that makes the poison", the real question is: Can you get the contaminants below the allowed limits? A new epoxy, or polyester boat tank will immediately begin to leach un-polymerized compounds into the stored water. A new steel tank will have a light coating of machine oil from the manufacturing process; unless, they have cleaned it with a de-greaser, then, 'trace' cleaner may be left behind.



I suggest you clean your tank, install cartridge filters (with a charcoal stage, charcoal is very effective at adsorbing the hydrophobic compounds in oil) then have the filtered water analyzed for trace oil residue. Some county water labs will provide that analysis for a relatively small fee. Then you can make an informed decision about whether to remove the tank.


Good luck.

[Rohan]

One question worth asking when considering which way to go with this. How often do you actually drink the water in your tanks? We carry separate bottled water for drinking, or use a Brita filter as do a lot of people. Our fresh water is really only used for bathing, washing dishes, and the toilet.

[gonesail]

any knucklehead that drains oil and gas into the bilge .. while leaving a water tank open .. needs to answer for what they did. other than that .. hot water and a lot of washing and rinsing. did you say what the tanks are made of?