Sunday, January 11, 2009

So you want to buy a house?...part 6-metals

Metals and the discoloration they cause! Discoloration problems are the next most prevalent problem in the well water in this area, mostly caused by deposits of iron and manganese that exist in the ground. Now iron in the water gives the water a bitter taste, but will not hurt you and unfortunately is not in a form the body can readily use either,. So irons big issue is that it can cause an orange-brown discoloration that most people will see in a 'clean' toilet bowl. There is also a bacteria which helps the iron look particularly ugly called appropriately enough an iron bacteria. This bacteria does not like humans and will never hurt us, but if it grows without oxygen present (called anaerobic and a condition not uncommon in wells), it will produce a nasty odor (Hydrogen Sulfide) that will make your water very unpleasant. Unfortunately, very few labs will test for this bacteria (The Stamford Health Department Lab does, it was my first introduction to the bacteria world in 1974) and its presence will create havoc on many treatment devices. Most of the time though, this bacteria will thrive in the back of a toilet bowl and will turn the bowl inside rust colored. The good news is that a cup of bleach every week will kill the bacteria and keep the discoloration out of the system. Most worrisome levels of iron are easily seen when you turn on the faucet, but a few have not been oxidized and will not be so apparent.
You notice that I did not talk about manganese with iron even though a low levels it is exactly the same as iron except it stains black-brown. Iron bacteria love it, it imparts a bitter taste to the water, is a stainer, at low levels is not dangerous and even healthful, but at high levels there is a real problem.
This issue was first found in a well water supply in a Japanese village that had been tainted by an industrial source of manganese and document first in 1965 (I believe). The neurological problems have been likened to mercury poisoning and are significant. The original document that I read (not the one I found and sited from the web and talked of levels of 30 mg/L in the water), talked of adults being affected primarily because manganese is essential in growing muscle and that is what growing children do best. Still, Connecticut has a maximum contaminant level of 0.5 mg/L in well water and levels above that should be treated.
Copper is still a different issue because there is very little native copper in the soil and that means any copper in the water is coming from the household plumbing. Copper will stain fixtures at very low, non-toxic levels a bright blue, blue-green or yellow-orange depending on the form it is found. It is considered toxic at levels over 1.3 mg/L.
Arsenic is a significant issue that we are just now coming to grips with. There is an EPA standard (0.01 mg/L) and it is considered a carcinogen. This was actually based on a tragedy that occurred in Bangladesh where wells were drilled to helped residents escape the terror of bacterial polluted water. The ground had significant natural levels of arsenic. It was used as a pesticide for apple orchards, as a wood preservative in pressure treated wood in the United States and there have been wells tested with levels over the USEPA action limit.
The Greenwich Health Department Lab is able to test for arsenic.
Lead is an issue only for older home (before 1977) with either lead solder (most common) or lead pipes (rare). It is a significant toxin for children under the age of 6 and will make the water taste 'sweet'. It is not common to find elevated levels in water in this area in wells, but can occur. It is also not common in water company water, but some homes in the late 1960's and 1970's have been found with elevated levels.
On the whole, serious problems from metals in well water are rare, but do exist. The more common issue is simple discoloration.
If a lab is certified to do metals, there are no testing issues.
I hope my next installment will deal with treatment issues.
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