Which regulation protects public health by limiting levels of contamination in drinking water under the Safe Drinking Water Act?

• A. Total Coliform Rule
• B. Code of Federal Regulations
• C. National Primary Drinking Water Regulations
• D. National Secondary Drinking Water Regulations

Answer: (C)

Regulations that protect public health by limiting contaminant levels in drinking water under the Safe Drinking Water Act are the National Primary Drinking Water Regulations. These are enforceable health-based standards that set maximum contaminant levels and the treatment and monitoring requirements water systems must follow. They’re designed to directly reduce health risks from drinking water.

National Secondary Drinking Water Regulations are non-enforceable guidelines focused on taste, odor, color, and other aesthetics, not direct health protections. The Total Coliform Rule is a specific monitoring rule within the broader primary standards, addressing a bacterial indicator, but the overarching health-based limits come from the National Primary Drinking Water Regulations. The Code of Federal Regulations is the publication of these rules, not the regulation itself.