Download POTABILITY SCAN LIST OF PARAMETERS PARAMETER MCL

POTABILITY SCAN LIST OF PARAMETERS
This document has been developed based on federal standards as of 01/23/06 to assist consumers interpret
their water test results. Contact your local Health Department for specific questions concerning these
guidelines or recommendations regarding testing parameters, test frequency or possible treatment options.
PARAMETER
MCL*
DESCRIPTION
Alkalinity
No Limit
The alkalinity of water is a measure of its ability to neutralize a strong
acid. A water with low pH and low alkalinity might be considered to be
corrosive. An alkalinity of 30 to 100 mg/l is desirable for domestic
purposes.
Sources include erosion of natural deposits, runoff from orchards,
pesticide residues, industrial waste and smelter operations.
A component of the water’s hardness. Calcium is found in soil and can
leach into water supplies affecting hardness, alkalinity and pH. Calcium
levels of 50 to 150 mg/l are recommended for domestic purposes.
Arsenic
0.01 mg/L
Calcium
No Limit
Chloride
250 mg/L**
Coliform Bacteria
0
Color
15 C.U.**
Color is a measurement of clarity or discoloration. Color is considered for
aesthetic reasons and can also be used to confirm problems with various
minerals and metals such as iron and manganese.
Copper
1.3 mg/L (action level)
1.0 mg/L**
This element can be found in some natural waters. Excessive amounts of
copper can occur in corrosive water that passes through copper pipes.
Copper in small amounts is not detrimental to health; however, higher
amounts will impart an undesirable taste to drinking water.
Hardness
No Limit
Hardness is caused chiefly by calcium and magnesium ions, and it is
expressed as milligrams of calcium carbonate (CaC03) per liter of water.
Hardness may vary from 0 to several hundred mg/l. Small concentrations
of hardness help combat corrosion of metallic pipes by forming a
protective coating. Appreciable amounts of hardness break down on
heating to form scale in boilers and on cooking utensils. Hard water
retards the cleaning action of soaps and detergents. Water showing a
hardness of less than 50 mg/l are relatively soft; 50-100 mg/l is medium
hard, and over 100 mg/l are exceedingly hard. Very soft water, usually
less than 30 mg/l of hardness, is likely to be corrosive. Hardness of 50 to
200 mg/l is desirable for domestic purposes.
Iron
0.3 mg/L**
Small amounts of iron are frequently present in water because of the
large amount of iron present in soil and because corrosive water will pick
up iron from cast iron pipes. The presence of high levels is considered
objectionable because it stains laundry and porcelain, and it also affects
the taste of beverages.
A component of road salt. Affects taste and may lead to corrosion of
pipes.
Coliform bacteria are widely distributed in nature. Contamination from
surface waters, septic systems and direct contamination from animal
feces can contribute to the growth of coliform bacteria in wells. The
presence of coliforms indicates the possibility that disease-producing
organisms may also be present in the water.
Lead
0.015 mg/L
(action level)
Lead is a metal formerly used in soldering joints in plumbing systems.
Can be caused by plumbing, solder or fixture deterioration. Lead can build
up gradually and can have effects on the brain and nervous systems.
Magnesium
No Limit
Manganese
0.05 mg/L**
A component of the water’s hardness. Magnesium is found in soil and
can leach into water supplies affecting hardness.
Naturally occurring element in soil. Although rarely present in excess of
one milligram per liter, manganese imparts black stains to laundry and to
plumbing fixtures.
Nitrate
10 mg/L
In drinking, water above the standard poses an immediate threat to
children less than three months of age. If the drinking water contains an
excessive amount of nitrate, it should not be given to infants under three
months of age and not used to prepare formula. Nitrates can be found in
fertilizers, feedlots, sewage; usually occurs in soil and mineral deposits.
Nitrite
Odor
pH
1 mg/L
3 TON**
6.5-8.5**
Part of the nitrogen cycle. Can be correlated to high levels of nitrate.
The presence of odor may be an indicator of possible contaminants.
A measure of hydrogen ion concentration in water and represents the
aggressiveness of the water towards pipes. Values range from 0-14. A
value of 7 indicates neutral water; values less than 7, increasing acidity;
and values greater than 7 indicates increasing alkalinity. Determination of
pH assists in the control of disinfecting and corrosion.
Sediment
None
Sodium
No Limit
(20 mg/L
ORSG)
A visual identification made for the presence or absence of sediment after
a period of standing.
The Office of Research and Standards Guideline has been established for
sodium at 20 mg/L which represents a level in water that physicians and
sodium-sensitive individuals should be aware of in cases where sodium
exposures are being carefully controlled.
Sulfate
250 mg/L**
Sulfate is widely distributed in nature and may be present in natural
waters in concentrations ranging from a few to several thousand
milligrams per liter. Because of the laxative effects of magnesium sulfate
and/or sodium sulfate, sulfate content should not exceed 250 mg/L.
Total Dissolved
Solids
500 mg/L **
The amount of dissolved materials present. High levels can damage
plumbing and limit the effectiveness of soaps and detergents. Remove by
filtration.
Turbidity
5.0 NTU
A suspension of fine particles floating in water. Usually caused by
bacterial contamination, organic matter, iron, manganese or silt from
erosion, runoff or discharges. May cause sediment.
* MCL – EPA Maximum Contaminant Level, represents the maximum permissible level of a contaminant in
drinking water.
** SMCL – EPA Secondary Maximum Contaminant Level, representing reasonable goals for drinking water.
These standards are developed to protect the aesthetic qualities of drinking water and are not health based.
EPA recommends secondary standards to water systems but does not require systems to comply. However,
states may choose to adopt them as enforceable standards.