MCLGs

Maximum Contaminant Level (MCL) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards. 

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 allow for a margin of safety and are non-enforceable public health goals. 

Chemical Contaminants (Carcinogens) If there is evidenee that a chemical may cause eancer, and there is no dose below which the chemieal is considered safe, the MCLG is set at zero. If a chemieal is carcinogenie and a safe dose can be deter mined, the MCLG is set at a level above zero that is safe. 

Microbial Contaminants For microbial contaminants that may present public health risk, the MCLG is set at zero because ingesting one protozoa, virus, or bacterium may cause adverse health effects. EPA is conducting studies to determine whether there is a safe level above zero for some microbial contaminants. So far, however, this has not been established. 

Microorganisms MCLG (mg/L) MCL or TTi (mg/L) Potential Health Effects from Ingestion of Water Sources of Contaminant in Drmking Water... 

Although there is no collective MCLG for this contaminant group, there are individual MCLGs for some of the individual contaminants ... 

Haloacetic acids dichloroacetic acid (zero) trichloroacetic acid (0.3 mg/L). Monochloroacetic acid, bromoacetic acid, and dibromoacetic acid are regulated with this group but have no MCLGs. 

MCLGs were not established before the 1986 Amendments to the Safe Drinking Water Act. Therefore, there is no MCLG for this contaminant. 

EPA ODW Maximum Contaminant Level Goals (MCLGs) for Inorganic contaminants 0 mg/L 40 CFR 141.51 EPA 1985g... 

Maximum boiling azeotropes, 8 807-808 Maximum Contaminant Level Goals (MCLG) for lead, 74 765 for vinyl chloride, 25 649, 650 Maximum Contaminant Levels (MCLs), 27 583... 

A total of 83 contaminants are currently required to be regulated under the SDWA of 1986, and 77 substances or classes of substances make up a priority list of contaminants for regulation after the EPA completes standards for the initial list of 83. Although the EPA was required to establish MCLs and maximum contaminant level goals (MCLGs) for 25 of the contaminants by January, 1991, and every 3 years thereafter, the EPA has not kept up with this pace. 

In addition, the Superfund Amendments and Reauthorization Act (SARA) of 1986 set the groundwater standards the same as the drinking water standards for the purpose of necessary cleanup and remediation of an inactive hazardous waste disposal site. The 1986 amendments of the SDWA included additional elements to establish maximum contaminant-level goals (MCLGs) and national primary drinking water standards. The MCLGs must be set at a level at which... 

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