Washington Level I Wastewater Study Guide

Operator Master has 91 Level I practice questions and 25 Level I math practice questions. Every question has an explanation. These are the topics the practice questions cover:

• Plant Operations53 questions
• Math and Calculations10 questions
• Pumps and Hydraulics8 questions
• Secondary Clarification5 questions
• Biological Treatment4 questions
• Headworks and Screening4 questions
• Grit Removal2 questions
• Laboratory2 questions
• Primary Treatment2 questions
• Solids Handling1 question

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 I 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.