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Letter Re: Purifying Water with Bleach

Mr. Rawles,
I've received and read the "Rawles Gets You Ready" preparedness course package. It made me think twice about a few things, since I do most of my prepping at Costco. I notice that someone has already mentioned the vitamin thing. Thanks for the tip about bear liver!

I also noticed that you recommended having bleach on hand, and in the storage life section, bleach is listed as having an indefinite shelf life. I'm sure you already know that is not the case. Regular liquid bleach is not stable, it breaks down gradually and eventually becomes just salt water over a period of 2 years, it's still usable at 1 year but you must use twice as much. We think dry swimming pool shock is better than liquid bleach because calcium hypochlorite will store in dry form nearly indefinitely (10 years), whereas liquid chlorine bleach loses half of it's potency after a year (use twice as much for the same effect) and is next to worthless after two years. Using dry swimming pool shock (calcium hypochlorite) you can mix your own liquid bleach on an as-needed basis and have it fresh and fully active. Its very much like the difference in storage life between whole kernel wheat versus ground flour. Dry shock (get the plain variety, with no algaecides or fungicides) is very inexpensive and can be gotten at any pool supply store. Here are some links with details:
The Epicenter
Greenspun
The relevant portion from the second site above: "Dry chlorine, also called calcium hypochlorite has the added benefit of extended shelf life. Providing it is kept dry, cool and in an airtight container, it may be stored up to 10 years with minimal degradation. If you want to keep chlorine in larger quantities, this is the item to store (according to Bingo1). It must be ONLY 65% calcium hypochlorite, no additional anti-fungals or clarifiers. In an EXTREMELY well ventilated area, (Hint: OUTSIDE!) add and dissolve one heaping teaspoon of high-test granular calcium hypochlorite (approximately 1/4 ounce) for each two gallons of water. Five pounds of dry pool bleach costs about $10-15, which will make about 92 gallons of bleach, which will sterilize 706,560 gallons of clear water, or 353,280 gallons of cloudy water."

Here are some additional tips on using calcium hypochlorite (swimming pool shock) for water purification:
From the EPA site:
"Granular Calcium Hypochlorite. Add and dissolve one heaping teaspoon of high-test granular calcium hypochlorite (approximately 1/4 ounce) for each two gallons of water. The mixture will produce a stock chlorine solution of approximately 500 mg/L, since the calcium hypochlorite has an available chlorine equal to 70 percent of its weight. To disinfect water, add the chlorine solution in the ratio of one part of chlorine solution to each 100 parts of water to be treated. This is roughly equal to adding 1 pint (16 oz.) of stock chlorine to each 12.5 gallons of water to be disinfected. To remove any objectionable chlorine odor, aerate the water as described below.
The treated water should be mixed thoroughly and allowed to stand, preferably covered, for 30 minutes. The water should have a slight
chlorine odor; if not, repeat the dosage and allow the water to stand for an additional 15 minutes. If the treated water has too strong a chlorine taste, it can be made more pleasing by allowing the water to stand exposed to the air for a few hours or by pouring it from one clean container to another several times"

Okay, a lot of people don't have a 12.5 gallon container laying around, so let's break it down. To make two gallons of the bleach, one heaping teaspoon of the calcium hypochlorite goes into 2 gallons of water. To make drinkable water, 2.5 tablespoons of the bleach goes into 1 gallon of water. Let stand covered 30 minutes, aerate to taste. Thought you would want to know. - J.W.

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