Choose the operator discipline—not a random pile of questions.
Read the core operating ideas, recognize common traps, then launch a targeted practice round and review your weak category.
Drinking-Water Treatment
Source water, coagulation, flocculation, sedimentation, filtration, disinfection, chemical feed, laboratory control, and treatment barriers.
Open study track →Drinking-Water Distribution
Pressure, storage, pumps, valves, mains, disinfection, sampling, flushing, cross-connection control, water age, and emergency response.
Open study track →Wastewater Treatment
Preliminary treatment, primary clarification, biological processes, secondary clarification, solids handling, disinfection, sampling, compliance, and troubleshooting.
Open study track →Wastewater Collection Systems
Gravity sewers, lift stations, force mains, cleaning, inspection, inflow and infiltration, overflows, confined spaces, and records.
Open study track →Operator Safety & Professional Judgment
Confined spaces, chlorine and chemical handling, lockout/tagout, PPE, electrical and mechanical hazards, sampling safety, communication, and incident records.
Open study track →Operator Math
Unit conversions, flow, volume, detention time, pounds formula, chemical feed, loading, pump relationships, and sludge calculations.
Open study track →Not sure which track applies?
Build your state and job route first. Treatment, distribution, wastewater treatment, and collections are not interchangeable everywhere.