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The information below is provided in order to assist you in understanding the meaning of your results from your water analysis. The limits listed below are set by the USEPA, the MA DEP, and any other regulatory agency for public drinking water systems and are not legally enforceable, but simply a guideline for private water sources. Con-Test Analytical Labs does not make recommendations on further actions for you water system. For more information on drinking water questions and concerns please vist the EPA's website.



Total Coliform Bacteria Coliform is the group of bacteria used to determine the general sanitary quality of a water source. If you have a positive coliform value, it may indicate an unsanitary condition for your drinking water or you may have no followed a sanitary procedure when collecting the sample. If you have a positive value after a second test then you may need to disinfect your well.
Alkalinity Alkalinity is a measure of a water sample's ability to neutralize acid. Ideally the alkalinity value should be in the range of 50-100 mg/L for drinking water.
Chloride The USEPA limits chloride to 250 mg/L for public drinking water. A value over this limit could indicate brine or road salt contamination.
Copper The USEPA has established an action level of 1300 ug/L (1.3 mg/L) for copper in drinking water. Results above this level may cause a blue-green staining of sinks, toilets and fixtures

Hardness is the total content of calcium and magnesium in a water sample. Water is qualified as "hard" or "soft" by the following criteria:

  • 0-75 mg/L = soft water
  • 75-150 mg/L = moderately hard water
  • 150-300 mg/L = hard water
  • More than 300 mg/L = very hard water
Iron The USEPA has set a limit of 300 ug/L (0.3 mg/L) for iron in public drinking water. While a high iron content in drinking water is not usually harmful, the level has been chosen to avoid staining and other aesthetic problems associated with high iron content.
Lead The USEPA has established a limit of 15 ug/L (0.015 mg/L) for lead in public drinking water. High levels of lead can cause serious health problems. A water treatment specialist should be consulted should your result be over the recommended limit.
Manganese The USEPA has established a limit of 50 ug/L (0.05 mg/L) for manganese in public drinking water. Results above that limit may give water a metallic taste and cause a black or brow discoloration in sinks and toilets especially if iron is present.
Nitrite and Nitrate The USEPA has established a limit of 10 mg/L for nitrate and 1.0 mg/L for nitrite in public drinking water. A result above this limit should be looked into as high concentrations of nitrates have been known to cause health problems in newborn babies. The presence of nitrate along with a positive result for total coliform bacteria could indicate a septic system or surface water contamination of your well water source.
pH A pH of 7.0 is considered neutral while values below 7.0 are called acidic and above 7.0 are called basic. As a pH value moves toward either end of the scale, the water becomes more corrosive. The USEPA recommends a pH value of 6.5 - 8.5 for public drinking water.
Sodium The MA drinking water limit for sodium is 20,000 ug/L (20 mg/L). Results with a higher value could indicate infiltration of road salt or natural salt water to the drinking water and could be unsuitable for those on a sodium restricted diet.