A wastewater screen with an operator using it.

Level 1 Wastewater Treatment Exam Study Guide

This interactive guide from UtiliLearn is designed for operators preparing for their Level 1 Wastewater Treatment Certification. It focuses on the key topics that often appear on the exam, including lagoons, safety, mechanical systems, process control, and lab testing. Each section includes concise, exam-focused information to help you study efficiently.

  • Types: Anaerobic, Aerobic, Facultative.
  • Stages: Waste Stabilization Ponds → Oxidation Ponds → Polishing Ponds.
  • Hydraulics: Prevent short-circuiting, maintain proper Hydraulic Retention Time (HRT), understand parallel vs series, avoid overloading.
  • Oxygen & pH: Algae produce O₂ (day) and consume O₂ (night); CO₂ causes pH swings; lagoon colours may indicate health (dark green, brown, red).
  • Operations & Maintenance: Control duckweed/cattails, dredge sludge, control algae blooms, repair riprap/berms.
  • Wastewater Content: BOD₅, TSS, pathogens, and nutrients (N, P, ammonia).
  • Exam Focus: Identify symptoms (green water, high TSS) and apply effective control measures.
  • Hazards: Hydrogen sulfide (H₂S), chlorine gas, confined spaces, electrical hazards, slips/trips.
  • PPE: SCBA, gas detectors, lockout/tagout for mechanical/electrical isolation.
  • Administration: Recordkeeping, work permits, incident reporting, compliance with safety regulations.
  • Pumps: Centrifugal (volute, impeller, wear rings, bearings, lantern rings) vs positive displacement (chemical dosing, vacuum draw).
  • Valves & Gates: Knife gate, butterfly, plug, ball, and sluice gates — function and uses.
  • Aeration Systems: Blowers, diffusers, and maintenance practices.
  • Activated Sludge: DO target (~2.0 mg/L), MLSS control, WAS & RAS adjustments.
  • Metrics: F/M ratio, MLSS, SRT, floc quality checks.
  • Upset Response: Adjust air for BOD changes; avoid >10% WAS change/day.
  • Maintenance: Lubrication, seal checks, vibration monitoring, winterizing.
  • BOD₅: Measures oxygen demand over 5 days at 20°C; numbers like 300 mL, 48 h holding time are exam-relevant.
  • TSS: Total Suspended Solids measurement.
  • pH & Alkalinity: Process stability and disinfection efficiency.
  • Wastewater Characteristics: Chemical (nutrients, ammonia, chlorine, metals) and physical (temp, colour, turbidity).
Made by operators, for operators — UtiliLearn Wastewater Exam Prep.
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