| Total
Coliform bacteria (TC) refers to bacteria that occur naturally in soil
and decaying vegetation. They may also be associated with human or animal
fecal contamination. In other words, they are in the dirt, manure and
surface water we walk through everyday. |
| Coliform
organisms do not normally grow in well water, because the water is cold
(10°C or 50°F) and either alkaline or acidic (pH). The earth has the
ability to filter bacteria out as the water moves through the ground.
However, once allowed into the well, coliforms will survive for a long time. |
E.
coli (Escherichia coli) are bacteria that are found in the intestines of
warm-blooded animals like dogs, cats, birds and humans. E. coli is a member
of the Coliform family of bacteria. Their presence in the well water may
indicate fecal contamination from a human or animal source. There are
numerous strains of these bacteria, some of which are very harmful.
E. coli 0157:H7 is a rare strain of these E. coli that is very toxic.
Although it could be found in contaminated water, the presence of E. coli in
your water sample does not mean that this toxic strain is present. |
EST.
Est. means that an estimate number of coliforms and or E. coli bacteria can
only be made. There has been an overgrowth of bacteria on the filter media,
but the lab is still able to see the growth of some coliforms or E. coli.
The numbers are therefore estimated. |
Overgrowth!
O/G means that bacteria other than coliforms have overgrown the growth
medium in the lab. These other bacteria may feed on iron, sulfur or some
other dissolved mineral in the well water or debris that has fallen into the
well. These bacteria may hide the presence of Coliform bacteria because they
grow faster and bigger covering over the smaller colonies of bacteria on the
filter media plate. |
| Do
not drink your water if bacteria are present! |
Leeds,
Grenville and Lanark District Health Unit -
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