Calling All Chem Geeks (incl. THE Chem Geek) re: storing pool chems

I'm here, now anyways! I was on vacation Friday and I don't have a PC at home.

I have to say, it's really nice to be breathing such clean air, having an entirely new duct system. I was in the crawl Saturday vacuuming work debris from the vapor barrier, then decided to vacuum the whole thing even though I would have to "crawl" as the height gradually diminished. And I noticed something that could shed more light on this whole situation. The crawl takes water. I'd guess about 40% of the earth below the double vapor barrier is wet after a heavy rain we'd had recently (double because I laid a black one when I bought the place 8 years ago and when my HVAC guy put in new heat pump last year he laid a white, thicker mil over the black one). You can easily see it because you can see a shiny translucence of the black plastic when you put weight on the white plastic. I confirmed by pulling it up in a few places and then touching it.

So could it be that all this moisture is what caused the oxidation, and not the MA leaching from either a defective cap or some normal outgassing at all? But then you have to consider, if there's a double-layer of vapor barrier isn't it keeping the moisture from gravitating upwards/through the two layers of plastic? The black mold in the main trunk line could've been because it was old and leaky, and in Alabama we do have a lot of humidity along with the increased humidity from the damp earth below the vapor barriers, plus the pool is only 20 feet away which would serve to potentiate all this humidity assuming it can work its way into the crawl.

So I guess I will never know for sure what caused the incredible oxidation, or if it was a mixture of the two. Since I can't afford $5-10K to have a foundation specialist fix the problem, I'm going to install a dehumidifier in the crawl with a direct line (whose specs are for some 3600 sq. ft. when the crawl is about 1100 sq. ft.) and hope that this will keep everything good and well. It will run a lot, so I probably will have to replace it every couple of years.

Since the new trunk line is commercial grade and is a solid metal unlike the old one which was made of fiberglass which is a perfect environment for mold, and additionally is wrapped, and since all ducts are new and everything is sealed so well along with a UV light, I think I should be fine there--my HVAC guy said nothing will be able to grow in that environ. Upon inspection of the joists I see no rot whatsoever, and the walls are made of concrete block and there is no visible mold on them, so I'm hoping to not have any more nightmares in my lifetime. Statistically, at 55 that's not a crazy amount of time. But you can bet that I will go inspect the crawl on a monthly basis now that I am so aware of the potential for problems.

Even so, my MA and bleach will now be stored in open milk cartons *behind* the pool house, in the open air and in the shade, well away from the upper yard and pool.

Thanks everyone for weighing in!

My HVAC guy, David, just called to see how I'm liking the ultra-clean air inside my house and after I expressed my gratitude (again), I told him about the wetness underneath the vapor barriers, and he said that's *normal* - it's sweating/condensation and it can't hurt anything because it's under the plastic, i.e., that's what they're for (which I knew, but still didn't quite grasp apparently). So I am quite relieved. I'm going to get a dehumdifier anyway to protect what he just called an industrial-grade duct system. What an extraordinary service, and extraordinary man.

And you can bet I won't store any MA or bleach in my garage, either, where my car of course is along with my new toy, a Gary Fisher hybrid bike. :)

Elsie, glad you're breathing clean air!

Thanks for starting this so I remembered to ask my questions :cool:

I hope your pool and new duct work never cause you any problems, but if they do... you know where to find your answers :)

What's the best way to dispose of extra "old" muriatic acid? I have a partial bottle that I want to get rid of... have not used or needed it in years. I know I should not just pour it down a drain or onto the ground. Is there a safe way to neutralize it?

While I'm certainly noot an expert on hazardous chems, I think that filling a ~30 gallon garbage bin with water, adding the acid and then enough soda ash (pH up or Super Washing soda to neutralize it) would be sufficient to allow you to just dump the bin on the driveway or lawn. :)

1 gallon of full-strength Muriatic Acid (31.45% Hydrochloric Acid) is neutralized by 8.4 pounds of pH Up / Soda Ash / Arm & Hammer Super Washing Soda or by 16.6 pounds of 20 Mule Team Borax.

Excellent! Now I know what to do and how much neutralizer to use.

It will actually take less than the amounts I indicated, especially for the soda ash, because it will result in carbon dioxide outgassing that will also raise the pH. Figure about 4-1/2 pounds instead of the 8.4 pounds (per gallon of acid). You should mix the soda ash in a bucket of water and then slowly add the acid to it. Wear goggles as there will be bubbling of carbon dioxide when you add the acid and you don't want anything splashing into your eyes.

Be careful not to breathe the fumes from the muriatic, as well as any that may be created while doing the mixing. MA fumes are truly AWFUL.