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Health Advisory Levels (HALs)

The maximum contaminant level (MCL) is a standard established by the United States Environmental Protection Agency, under the Safe Drinking Water Act. It represents an acceptable level of a chemical under specified conditions that ensures the safety of a public drinking water supply. MCLs are used by DEP to regulate the level of chemicals allowed in drinking water. A full list of chemicals with existing MCL values are available in Tables 1-5 at the end of DEP rule 62.550 .

Health Advisory Level (HAL)s are developed when a chemical is found in drinking water and no regulatory standard (MCL) exists for the chemical. The HAL concentration of a chemical in drinking water is a value that, based on the available data, is virtually certain not to cause adverse human health effects if consumed over a lifetime. HALs provide guidance for the public and the Department of Environmental Protection (DEP) on the potential for these chemicals to cause harm to humans.

View the complete Environmental Chemistry Analyte List (249kb PDF) , and each compound's MCL or HAL value.