Washington Level II Wastewater Study Guide

Operator Master has 118 Level II practice questions and 25 Level II math practice questions. Every question has an explanation. These are the topics the practice questions cover:

• Plant Operations35 questions
• Math and Calculations21 questions
• Pumps and Hydraulics18 questions
• Biological Treatment11 questions
• Laboratory9 questions
• Disinfection7 questions
• Solids Handling7 questions
• Secondary Clarification5 questions
• Primary Treatment3 questions
• Grit Removal2 questions

This list describes Operator Master's practice, not the official exam outline. See the official resources below for what the exam covers.

1. Practice One Topic at a Time

   Answer practice questions and read each explanation, including for the ones you get right.

   Start Level II Practice→

2. Learn the Math

   Work through the Math Center topics step by step. The pie wheel lessons show how to set up and rearrange a formula.

   Open the Math Center→Pie Wheel Lessons→

3. Take a Full Practice Exam

   The timed practice exam gives a score by topic at the end, so you can see where to spend your time.

   Open the Full Practice Exam→

4. Review and Repeat

   Go back to your weakest topics, practice them again, then take another full practice exam.

• Washington Department of Ecology: certification information covers applying, the exam, study resources and who to contact.
• Water Professionals International (WPI): Need-to-Know Criteria lists what wastewater treatment exams cover. Check with Ecology which materials apply to your exam.