Water Quality Regulations and Public Health
The Water Quality Regulations and Public Health domain tests your knowledge of the Safe Drinking Water Act framework as Kentucky applies it: which contaminants are regulated, how compliance is calculated, and how the public is notified. Expect questions on MCLs, treatment techniques, monitoring, the Consumer Confidence Report, and public notice.
Core rules and concepts
- Primary standards protect health and are enforceable. MCLs are maximum contaminant levels; MCLGs are non-enforceable health goals.
- Treatment techniques apply where an MCL is not practical, such as filtration and disinfection for surface water and lead/copper corrosion control.
- Secondary standards address aesthetics, such as iron, manganese, chloride, and odor; they are not health-based.
- Compliance is often based on a running annual average or a percentile, not a single sample.
- The CCR must be delivered by July 1 each year and summarize the previous calendar year's water quality and compliance.
- Public notice timing depends on tier: Tier 1 for immediate health risks, Tier 2 for shorter-term risks, Tier 3 in the CCR.
Worked example
A system's quarterly TTHM results are 70, 85, 95, and 80 µg/L. The LRAA is (70 + 85 + 95 + 80) ÷ 4 = 82.5 µg/L. The TTHM MCL is 80 µg/L, so the LRAA exceeds the MCL and the system has a violation. Do not average only the highest quarters; use all required quarters in the locational running annual average.
Traps
Treating an MCLG as enforceable; using one sample to decide compliance; missing the July 1 CCR deadline; confusing Tier 1 and Tier 2 notice timing; forgetting that a monitoring violation can require public notice even when water quality was fine.