Exam Prep Guides
2-Book Bundle · Best Value
Exam Day & Every Day
The Complete Exam Guide + Activated Sludge: Bugs, Basins & Beyond. Pass the test, then understand the plant — a $34 value, together for $29.
New · Grade 2 · Trap Notes
Grade 2 Practice Exam Pack
100 exam-style questions across 11 sections with every answer explained — and every planted trap named in the key. 17 fully worked calculations. Companion to the free Grade 2 video review.
New · Treatment · Nutrient Removal
The Bardenpho Process
Biological nutrient removal, worked by mechanism: the recycle ceiling, the full process family, bio-P and chemical dosing math — plus 7 worked problems and a 40-question practice exam with explained answers.
New · Collections · ABC Class I
Pipeline Cleaning & Maintenance
The collection system study guide: every cleaning method compared, H₂S and root chemistry, every formula worked — plus a full practice exam with explained answers.
Featured · All Topics · No Math
Complete Exam Guide
200 conceptual questions across 12 major exam topics. The essential starting point for any operator preparing for Class I or Class II certification.
Deep Dive · Includes Math
Activated Sludge: Bugs, Basins & Beyond
150 questions across 11 subtopics — microbiology, SRT & F/M calculations, RAS/WAS control, secondary clarifiers, and troubleshooting. Class I & II tagged.
Water & Wastewater · Review + Exam
Introduction to Laboratory Methods
13 sections of lab content review plus 100 practice questions — safety, glassware, pipets, solutions, sampling, pH, alkalinity, QA/QC, chlorine, and DO.
Free Resources
Free Crossword Pack
7 themed puzzles, 101 exam terms — active recall that doesn’t feel like studying.
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Free Practice Questions
10 exam-style questions with full explanations. No purchase required.
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Wastewater Glossary
Plain-English definitions of 50+ essential treatment terms.
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Exam FAQ
Answers to the most common exam prep questions.
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Certification Guide
How operator certification works — grades, requirements, state programs.
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