MCL- Maximum Contaminant Level allowed by the CT Department of Public Health in Drinking water.

IMPORTANT NOTE: When any physical property exceeds the MCL, knowledge concerning the chemical quality is important in order to determine what treatment, if any, is required to make the water acceptable for use.

Coliform Bacteria: Not disease producing organisms in themselves, coliform bacteria are an indicator of disease producing organisms such as e.coli. When coliform bacteria are present, it is a good indication the source of the water may have been contaminated by surface water or fecal material and may contain disease producing organisms. Chlorination is the best method for eliminating bacteria from water, but the source of contamination should be located and treated so that the problem does not recur.

MCL: Absence of both Total Coliforms & e. coli

If bacteria are found in your water sample, you will be notified immediately. A retest is recommended to confirm the presence of bacteria. If the retest is also positive, you should consult a plumber or other professional for inspection of the well integrity and shock or permanent chlorination of the well.

Odor MCL: 2 Odor in water is caused mostly by organic and some inorganic chemicals. These chemicals may come from natural, agricultural, or domestic sources. The MCL has been set according to aesthetic values but acceptable water should be free from any objectionable odor.

For more information on odor in water see also:

http://ohioline.osu.edu/aex-fact/0319.html
http://www.hhs.state.ne.us/enh/feswater.htm

Color  MCL:15 Color in water may be caused by dissolved organic material from decayed vegetation such as peat or humus material and/or certain natural metallic ions such as iron or maganese. While color is not harmful, it is objectionable, and is therefore often treated.

Turbidity MCL: 5 Turbidity is the presence of suspended material such as clay, silt, plankton, finely divided organic material and other organic materials. Readings in excess of 5 units are detectable in a glass of water, and are usually objectionable aesthetically. The most common method of removal is with a filter system.

pH MCL: 6.4-10.0 pH is a measure of the acid or alkaline content of water. Water with low pH (acidic) or a very high pH (basic) is corrosive to plumbing, and may cause leaching of toxic materials such as lead or copper. Soda ash can be added to the feed water to effectively raise the pH.

Hardness MCL: 50-150 mg CaCO3/L/100mL Calcium and magnesium salts are the major cause of hardness in water. Although not detrimental to health, hard water retards the cleaning action of soaps and detergents. When hard water is heated it will deposit a hard scale on heating coils and cooking utensils with a consequent waste of fuel. A water softening system is the most common method of lowering the hardness level.

The following is a scale on which to assess your water hardness:
 0-75......................Low/Soft
 76-150.................Moderate
150-250...............Hard
250 or greater.....Very Hard

Copper Action Level: 1.3 mg/L  Copper in small amounts is not considered  detrimental to health but will impart an undesirable taste to drinking water. For this reason, the recommended limit is at 1 mg/L. Copper salt is often used in water supply systems to control biological growth in reservoirs and distribution pipes.

Iron MCL: 0.3 mg/L (Desirable limit) Iron levels above 0.3 mg/L can discolor fixtures and laundry and may impart a metallic taste to water. Iron is frequently present in water because of the large amounts present in soil. Corrosive water will also pick up iron from pipes. Common methods for removing iron from water are aeration or chlorination of the water followed by filtration of the iron.

Manganese MCL: 0.05 mg/L (Desirable limit) Manganese ranks eighth among the elements in order of abundance. More than 0.005 mg/L in your drinking water may produce a brownish black stain in laundry and fixtures and may impart objectional odor and taste. It is usually found along with iron in the soil with a high mineral content. Oxidation followed by a greensand filter is a common method for manganese removal.

Sodium MCL: 28 mg/L Sodium content of water is relatively unimportant for healthy persons because the intake of sodium from other food and drink is so much greater. Persons following a low sodium diet because of hypertension or kidney or cardiovascular disease, however, should be concerned with the elevated level of sodium. The usual sodium diet allows 20 mg/L in drinking water. Elevated sodium levels are likely to be seen with the use of a water softener. Other possible causes are run-off from salting or sewage contamination.

Chloride MCL: 250 mg/L The MCL for chloride was established primarily for aesthetic reasons. The concentration at which the average person can detect a salty taste in water is 250 mg/L. A very high chloride level can lead to corrosiveness of water on pipes and heating equipment and is usually associated with a high sodium level. Elevated chlorides may be caused by sewage contamination, run-off from road salting, or an improperly maintained water softener.

Nitrate MCL: 10 mg/L An elevated nitrate-nitrogen level may be an indication that agriculture fertilizer or waste disposal is polluting the water. The MCL of 10 mg/L has been established to prevent a disease called methemoglobinemia, "Blue baby disease" in infants. Nitrates can be removed by reverse osmosis and ion exchange resins.

Ammonia: Ammonia-nitrogen is a product of the microbiological decay of plant and animal protein and is commonly used in commercial fertilizers. Ammonia- nitrogen in ground waters is normal, unless the nitrite, nitrate-nitrogen, or bacteria levels are elevated, High ammonia nitrogen is of little concern.

Lead Action Level: 0.015 mg/L Lead is a serious cumulative body poison for children and adults. Lead in water may come from industrial, mine, and smelter discharge or from dissolution of old plumbing. Therefore lead analysis is typically performed on a first draw sample.