Standardized Wastewater Treatment Operator Exams

Wastewater Treatment Operator Need-to-Know Criteria

Need-to-Know Criteria outline the content that will be covered on WPI’s standardized examinations provided through ABC Testing, a WPI service.

• 2025 Wastewater Treatment NTK Criteria
• 2019 Wastewater Treatment NTK Criteria

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Wastewater Treatment Operator Formula/Conversion Table

WPI standardized exams are administered with a Formula/Conversion Table containing mathematical formulas and common abbreviations that may be present on the exam.

• Wastewater Treatment Operator Formula/Conversion Table

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Wastewater Treatment Operator Exam References

The following are approved as reference sources for WPI’s standardized wastewater treatment operator examinations. Operators should use the latest edition of these reference sources to prepare for the exam.

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California State University, Sacramento (CSUS) Foundation, Office of Water Programs

• Operation of Wastewater Treatment Plants, Volume I and Volume II
• Advanced Waste Treatment
• Utility Management
• Manage for Success

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Michigan State University

• Supervisory Management in the Water/Wastewater Field

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National Environment Training Center for Small Communities (NETCSC)

• Protecting Your Community’s Assets: A Guide for Small Wastewater Systems

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Water Environment Federation (WEF)

• *Operation of Water Resource Recovery Facilities, MOP 11
• **Safety, Health, and Security Standards for Water Resource Recovery, MOP 1, 7th Edition
• ***Activated Sludge and Nutrient Removal
• ****Wastewater Treatment Fundamentals
• Managing the Water and Wastewater Utility

*This WEF text replaces the previous WEF title, Operation of Municipal Wastewater Treatment Plants – Manual of Practice No. 11 **This WEF text replaces the previous WEF title, Safety & Health in Wastewater Systems, Manual of Practice No. 1 ***This WEF text replaces the previous WEF titles, Activated Sludge: Manual of Practice OM-9, and Operation of Nutrient Removal Facilities ****During the exam development process in 2017 & 2018, WPI’s Subject Matter Expert volunteer exam item writers had the opportunity to evaluate and incorporate information from the first volume of the Water Environment Federation’s Wastewater Treatment Fundamentals which at the time was set for release in August 2018.

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Regulations

• United States: Code of Federal Regulations, Title 40
• U.S. state regulations (contact information for state certification programs is available on the OpCert Program Contacts page)
• American Public Health Association (APHA), American Water Works Association (AWWA), and Water Environment Federation (WEF): Standard Methods for the Examination of Water and Wastewater
• Canadian provincial and territorial regulations (contact information for state certification programs is available on the OpCert Program Contacts page)