Wastewater operator exam and certification FAQs

Minnesota statutes and rules governing certification:

Anyone who has full and active responsibility for the daily on-site operation of a wastewater facility or a portion of the facility must be certified in a class equal to or higher than the class of the facility.

Wastewater facilities fall into two classes

  • Treatment facilities are classified A, B, C, and D according to a rated point system based on the unit processes, loading to the plant, and the permit's final effluent limitations
  • Type S systems — collection, pumping, and conveyance facilities distinctly separate in operation from treatment facilities — are classified S-A, S-B, S-C, and S-D based on the community's population. Where a type S facility is not distinctly separate, it is considered part of the treatment facility.
    • Class S-A: serving a population of 50,000 or more
    • Class S-B: serving a population of 15,000 to 49,999
    • Class S-C: serving a population of 1,500 to 14,999
    • Class S-D: serving a population of less than 1,500

All exams are closed book. You will be given a formula book. Bring a non-programmable calculator (no smartphones) and a pencil. A passing grade is 70 out of 100.

No, the exams are not the same. Each class of exams stress what you need to know on the job.

If you meet the education and experience requirements for the exam you need to take, submit

  • An application
  • $55 exam fee (non-refundable)
  • Position description or job duties
  • Time of service, name and phone number of supervisor(s)

at least 15 days before to the examination date. If you are substituting educational experience for operating experience, submit a copy of a college diploma or other proof of school attendance or graduation.

Class A requirements

  • Certified as a Class B operator for at least two years
  • High school diploma or equivalent

And EITHER

  • Eight years experience in the operation, including two years in management, of a class A or B facility or similar industrial facility

OR

  • Bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science and four years experience in the operation, including two years in management, of a Class A or B facility or similar industrial facility

Class B requirements

  • Certified as a Class C operator for at least one year
  • High school diploma or equivalent

And EITHER

  • Six years experience in the operationof a class A, B, or C facility or similar industrial facility

OR

  • Bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science and two years experience in the operation of a Class A, B, or C facility or similar industrial facility

Class C requirements

  • High school diploma or equivalent

And EITHER

  • Three years experience in the operation of a class A, B, C, or D facility or similar industrial facility

OR

  • Bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science and one year of experience in the operation of a Class A, B, C, or D facility or similar industrial facility

Class D requirements

  • One year experience in the operation of a Class A, B, C or D facility or in a related field

OR

  • Completed a post-secondary program of courses in water or wastewater technology approved by the agency at an accredited institution

Class S-A, S-B, S-C and S-D

  • High school diploma or equivalent
  • The same education and experience required for a regular wastewater certificate in the same class; experience must be in a wastewater treatment facility or type S facility
  • Applicant for an S-A type certificate must be certified as an S-B or B facility operator for at least two years
  • Applicant for a type S-B certificate must be certified as an S-C or C facility operator for at least one year

Substitutions for experience

At least 50% of the experience required must be obtained in a wastewater treatment facility. The other 50% may be obtained in a type S collection facility or drinking water treatment system, in a class no more than one class below the exam class. One year operating a water supply system or wastewater treatment facility is considered equal to a year of high school. Experience that is substituted for education cannot also be used to satisfy experience requirements.

Completing 40 contact hours of courses related to wastewater treatment or water supply will provide a one-month credit towards experience requirements. Education substituted for experience may not reduce the experience requirement to less than one year.

No. The agency will notify you if you pass the exam. Then you must submit the $45 certification fee within 90 days to become certified. If you don't submit the fee within 90 days, you must apply for re-examination.

A certificate expires every three years and must be renewed by 30 days after its expiration date. Renewal requires a $23 non-refundable renewal fee and documentation of training attended during the three years of certification. Fifty percent of the training hours must be in approved directly related wastewater operations training. The other 50% may be in approved training related to wastewater. If you attended training that was not sponsored by the MPCA, you must submit proof of attendance and a copy of the schedule or program.

Training hour requirements for renewal:

  • Class A and S-A = 32 hours (16 hours direct/16 hours related)
  • Class B and S-B = 24 hours (12 hours direct/12 hours related)
  • Class C and S-C = 16 hours (8 hours direct/8 hours related)
  • Class D and S-D = 8 hours (4 hours direct/4 hours related)

You can retake the exam after three months. We can identify the topics of incorrect answers upon request, to help you focus your areas of study.

Yes, if you request to review it within 60 days of notification of the results. When you review your exam, you may not take notes or be given the correct answers. The exam review is intended as a guide to show you where you may want to concentrate your study areas.