Personal Exam Self Tester (PEST)

NOTE: We are aware that the Vellosoft/PEST website is currently unavailable. We are working on a solution.

What is the PEST?

PEST is a software program that can be used to generate quizzes with multiple-choice, fill-in-the-blank, true/false, and drag-and-drop type questions. We, along with the cooperation of the Commode Commandos at the Littleton/Englewood Wastewater Treatment Plant and Julie Koehler from Integra Engineering, have used the PEST to generate study questions for the operator certification exams.

The original wastewater PEST database contains about 1200 questions in a variety of industrial and domestic wastewater treatment categories. The water PEST database contains about 600 questions.


Wastewater Questions – Over 1100 questions in municipal and industrial wastewater

PEST Version / PDF

NEW Wastewater Questions – A small update for disinfection, phosphorus removal, solids, and pumps.


Small System Water – Over 600 questions for small water systems

PEST Version /PDF

Collection Systems  (very small so far at 190 questions, but in progress).  For some more collections training questions, try this website: www.sewergeek.com

PEST Version / PDF

If you have any trouble downloading or installing the software, contact us at or 303-489-9226.