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GBlist: Re: Water Quality

you wrote:

<"What to do?  I sent an RFP to 8 different water treatment companies, and 
they were in complete disagreement as to the solution.  Here were the 
various options:

1. Water softening.  This is the standard approach.  It uses sodium 
("soft") to remove the calcium and magnesium ("hard").  Since it already 
has too much sodium, I thought this was a terrible idea.

2. Water softening using a potassium salt instead of sodium.   Some 
people said this was great, others said it would be no help, and I am 

3. Reverse Osmosis (sometimes combined with above).  This removes 
everything, but is costly, actually uses water, and the message above 
seems to indicate the quality might not be as good as suppossed.

4. Venturi chamber.  This is really wierd, but one proposal said by 
"micronizing" the water, the minerals would not be a problem (?).

5. "Nano" filter.  This is like an RO, but with a larger screen size, so 
the cost is reduced and less water is wasted.

6. Anion softener.  This will take out the sodium, but not the calcium, 
so needs to be used in combination.

7. Forget the wells, and collect rainwater from the roof.  If we had more 
than 15" of precipitation/year, this would be the preferred choice.  As 
it is, we might do this as it will dilute the well water.

8. Haul water from town.  Not a good long term plan.

Any thoughts, suggestions? " >

How about using  rainwater for drinking/ cooking water and the well water for
washing, bathing, etc.?
Fit a third tap (do you call these something strange like faucett in the USA
?) on kitchen sinks and   washbasins piped to the rainwater supply, maybe
also using a 1micron ceramic filter and/ or UV filter for safety sake...

Just an idea, as the best solution for a particular water system usually
takes a lot of thought ( & more knowledge than I have).
Reverse osmosis & nanofiltration can use up a lot of pumping energy because
of the pressures required, & can be quite expensive.

Matthew Hill
Leeds Environmental Design Associates

Reverse osmosis & 
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