DRINKING WATER STANDARDS
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pH	5.0 - 9.0	SAFE
TOTAL DISSOLVED SOLIDS	30 - 900 ppm	SAFE
ELECTRICAL  CONDUCTIVITY	0.05 - 1.5 mmho/cm	SAFE
MAGNESIUM	Less than 400 ppm Mg	SAFE
TOTAL HARDNESS	0 – 75 ppm CaCO3  75 – 150 ppm CaCO3 150 – 300 ppm CaCO3 300 + ppm CaCO3	SOFT WATER MODERATLY HARD WATER HARD WATER VERY HARD WATER
SULFATE-SULFUR	Less than 83 ppm SO4-S	DESIRABLE
CHLORIDE	Less than 250 ppm Cl	SAFE
TOTAL ALKALINITY	Less than 400 ppm CaCO3	NO PROBLEM
IRON	Less than 0.3 ppm Fe	DESIRABLE
MANGANESE	Less than 0.05 ppm Mn	DESIRABLE
COPPER	Less than 1.0 ppm Cu	DESIRABLE
FLUORIDE	0.75 – 1.50 ppm F	SAFE
NITRATE-NITROGEN	Less than 10 ppm NO3-N	SAFE

If the nitrate level is above 10 ppm, there is cause for concern. A safe alternate source of water should be found for infants under six months of age and pregnant mothers (because of the danger of prenatal methemoglobinemia). A nitrate-nitrogen level over 10 ppm is less critical if only adults and older children will be drinking the water. You may wish to consult with you personal physician or a health professional before deciding on a course of action. Boiling will not reduce the nitrate levels in water.

COLIFORM No Colonies per 100 ml SAFE
BACTERIA See below for further details on Bacteria

(ppm is the same as mg/L)

Drinking Water
Bacteriological Testing

The test routinely performed on drinking water to determine water purity is the total coliform analysis. Coliform bacteria are associated with contamination from the intestinal tract of warm-blooded animals.When these bacteria are present in water, they may cause vomiting and /or diarrhea. Due to this association, the Environmental Protection Agency has designated total coliform bacteria as a standard that is used to determine water purity. Non-coliform bacteria may also be present in water, but no sanitary significance or limits have been placed on this group at this time.It should be pointed out that a water sample contaminated with coliform bacteria is not necessarily unsafe for consumption. It is only when the coliform bacteria contain pathogenic bacteria (disease causing organisms) that the supply is unsafe. The presence of coliform bacteria indicates that the bacteria has been introduced into the water supply by 1) human contamination, such as, an individual performing maintenance on the supply; 2) poor well construction, allowing surface water to seep into the well; or 3) the aquifer is contaminated. The laboratory does not distinguish between pathogenic and non-pathogenic bacteria, therefore all samples contaminated with coliform bacteria should be considered as unsafe for consumption.
Coliform Test report Methods


A, Coliform Density per 100 ml

The coliform density per 100 ml must be 0. Samples that contain any coliform bacteria per 100 ml do not meet the bacteriological standard for purity. Ideally coliform bacteria must be absent in a 100 ml sample.
B. (TNC) Too Numerous to Count

“Too numerous to count” describes a condition in which excessive numbers of non-coliform bacteria prevent the accurate determination of coliform bacteria. Due to the excessive numbers of non-coliform bacteria present, it cannot be determined whether this sample meets the bacteriological standard for purity.A replacement sample is requested.