Constituents:
Components or elements found in drinking water.
Maximum Contaminant Level (MCL):
The highest level of a contaminant that is allowed in
drinking water. Primary MCLs are set as close to the PHGs (or MCLGs) as is economically and technol-
ogically feasible. Secondary MCLs are set to protect the odor, taste, and appearance of drinking water.
Maximum Contaminant Level Goal (MCLG):
The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs are set by the USEPA.
Maximum Residual Disinfectant Level (MRDL):
The level of a disinfectant added for water treatment that may not be exceeded at the consumer’s tap.
Maximum Residual Disinfectant Level (MRDL):
The level of a disinfectant added for water treatment that may not be exceeded at the consumer’s tap.
Maximum Residual Disinfectant Level Goal (MRDLG):
The level of a disinfectant added for water treatment below which there is no known or expected risk to health. MRDLGs are set by the USEPA.
Primary Drinking Water Standard (PDWS):
The MCLs and MRDLs for contaminants that affect health along with their monitoring and reporting requirements, and water treatment requirements.
Public Health Goal (PHG):
A required process intended to reduce the level of a contaminant in drinking water.
Regulatory Action Level:
A required process intended to reduce the level of a contaminant in drinking water.
Treatment Technique (TT):
A required process intended to reduce the level of a contaminant in drinking water.
THE FOUR TERMS TO EXAMINE
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Primary Standards |
| Mandatory health-related standards that may cause health problems in drinking water. | |
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Secondary Standards |
| Aesthetic standards (non health-related) that could cause odor, taste, or appearance problems in drinking water. | |
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Unregulated Parameters |
| Information about contaminants that are monitored but are not currently regulated by federal and state health agencies. | |
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Additional Parameters |
| Information that may also be of interest to our customers. |