Which option best describes Secondary Drinking Water Regulations?

• A. Non-enforceable guidelines for contaminants that affect taste, odor, or appearance.
• B. Enforceable limits for taste and odor.
• C. Health-based goals for contaminants.
• D. Non-federally enforceable guidelines for contaminants that affect taste, odor, or appearance.

Answer: (D)

Secondary Drinking Water Regulations are guidelines that address how water should taste, smell, and look—matters of aesthetics rather than direct health protection. They’re not enforceable standards at the federal level, though utilities may voluntarily follow them or states may choose to adopt them as enforceable rules. This is why the best description is that they are guidelines for taste, odor, or appearance that are not federally enforceable. The other options mix in enforceable limits or health-based goals, which describe different parts of the regulatory framework (primary standards for health and MCLGs as health-based goals), so they don’t fit as accurately.