Regulations, Reporting, and Public Health
What to know
Regulatory knowledge ties operations to public health protection. Understand the Safe Drinking Water Act framework, National Primary Drinking Water Regulations (NPDWR), Maximum Contaminant Levels (MCLs), Maximum Contaminant Level Goals (MCLGs), Treatment Techniques (TTs), and Secondary MCLs. Know the major rules: Total Coliform Rule / Revised Total Coliform Rule (with assessment and corrective action triggers), Surface Water Treatment Rule (turbidity and CT requirements), Stage 2 DBP Rule, Lead and Copper Rule, Arsenic Rule, and Consumer Confidence Report (CCR) requirements. Understand monitoring and reporting obligations, public notification tiers (immediate, 24-hour, 30-day, annual), and operator certification requirements. Know that MCLs are enforceable limits while MCLGs are health goals, often zero for carcinogens.
Traps
Questions often confuse MCL with MCLG, or assume a TT is a concentration limit - it is a required practice. Watch for public notification tier errors and for confusing CCR (annual, all customers) with violation notice (event-driven). Another trap: assuming a positive coliform result alone is an MCL violation - repeat sampling and assessment rules apply.
Worked example / rule of thumb
If a system exceeds the nitrate MCL, it must notify the public at the highest applicable tier and report the violation, not merely adjust treatment quietly. Rule of thumb: MCL = enforceable number; MCLG = health goal; TT = required action.
Study tip
Pair each rule with its key metric and its public notification trigger.