Under the Safe Drinking Water Act, what is the primary purpose of Maximum Contaminant Levels (MCLs)?

Under the Safe Drinking Water Act, what is the primary purpose of Maximum Contaminant Levels (MCLs)?

• A. To establish permissible levels of pollutants in surface water
• B. To define the maximum concentration of contaminants allowed in drinking water
• C. To regulate the discharge of pollutants into navigable waters
• D. To set standards for the treatment of industrial wastewater

Answer: (B)

Maximum Contaminant Levels are the legally enforceable upper limits for how much of a contaminant can be present in finished drinking water. They exist to protect public health by ensuring drinking water stays within safe concentrations, and utilities must monitor, treat, and report to keep within these limits. The levels are chosen based on health risk, available treatment technologies, and practical feasibility for water systems. This focus on drinking water, rather than surface water quality, discharges, or industrial wastewater standards, is what makes this the primary purpose of MCLs.

Maximum Contaminant Levels are the legally enforceable upper limits for how much of a contaminant can be present in finished drinking water. They exist to protect public health by ensuring drinking water stays within safe concentrations, and utilities must monitor, treat, and report to keep within these limits. The levels are chosen based on health risk, available treatment technologies, and practical feasibility for water systems. This focus on drinking water, rather than surface water quality, discharges, or industrial wastewater standards, is what makes this the primary purpose of MCLs.