Wastewater operator certification FAQs


Below are some common questions and answers about Minnesota's certification laws and regulations, and the MPCA Certification Program. For reference, see Minn. Statute 1971, Section 115.71, and the Minn. Rules 9400.0200 to 9400.1400.

For questions about wastewater operation certification and exams, email Tracy Finch or call 651-757-2103.

A wastewater treatment facility operator means a person who has "direct responsibility" for the operation of, or operates, a wastewater treatment facility.

A wastewater treatment facility means any plant, disposal field, lagoon, or other works, installed for the purpose of collecting, pumping, treating, stabilizing or disposing of sewage, which is actually used or intended for use by the public or by any considerable number of persons.

A person may not operate a wastewater treatment facility unless the facility maintains at least one person that:

  • is certified in a class equal to or higher than the class of the facility, and
  • has full and active responsibility for the daily on-site operation of the facility or of a portion of the facility, if an additional operator(s) with appropriate certification are responsible for the remaining portions of the plant.

There are two separate classes of wastewater facilities; 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 final effluent limitations. The type S or collection system, is classified S-A, S-B, S-C and S-D and is determined by the population of the community.

A type S facility means a system of collection, pumping, and conveyance facilities distinctly separate in operation from a facility which treats, stabilizes, or disposes the wastewater. Where a type S facility is not distinctly separate, it is considered to be 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 or more but less than 50,000;
  • Class S-C, serving a population of 1,500 or more but less than 15,000;
  • Class S-D, serving a population of less than 1,500.

Direct responsibility means the wastewater operator having full and active responsibility for the operation of a portion of, or all of, a facility or wastewater collection system.

A city manager, superintendent of public works, or other administrative official shall not be deemed to have direct responsibility of a wastewater treatment facility, unless their duties include the day-to-day operation of the facility.

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.

Exams are given on the last day of most of the training courses which are offered by the MPCA. Several additional exam sessions are also offered — see the training calendar for specific dates.

An operator desiring to take an examination must file an application at least 15 days prior to the examination date along with a non-refundable $55.00 fee for examination. You must meet the education and experience requirements for the appropriate examination. A copy of a college diploma or other proof of school or college attendance or graduation, must be submitted with the application, if the applicant is substituting educational experience for operating experience. Make sure to provide time of service, Position Description / job duties and supervisor(s) name and phone number for verification.

Class A

  1. You must have been certified as a Class "B" operator for a period of two years, and
  2. have a high school diploma or equivalent with at least eight years experience in the operation, including at least two years as a part of the management, of a class A or B facility or similar industrial facility; or
  3. have a bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science, and submit satisfactory evidence of at least four years of experience in the operation, including at least two years as a part of the management, of a Class A or B wastewater treatment facility, or similar industrial facility.

Class B

  1. You must have been certified as a Class "C" operator for at least one year, and
  2. have a high school diploma or equivalent with at least six years of experience in the operation of a Class A, B or C facility, or a similar industrial facility; or
  3. have a bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science, and submit satisfactory evidence of at least two years of experience in the operation of a Class A, B or C wastewater treatment facility, or similar industrial facility.

Class C

  • An applicant must have a high school diploma or equivalent with a minimum of three years of experience in the operation of a Class A, B, C or D wastewater treatment facility, or similar industrial facility, or
  • have a bachelor's degree from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in a physical or biological science, and submit satisfactory evidence of at least one year experience in the operation of a Class A, B, C or D wastewater treatment facility, or similar industrial facility.

Class D

  1. have at least one year experience in the operation of a Class A, B, C or D facility, or in a related field; or
  2. satisfactorily 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

  1. An applicant must have a high school diploma or equivalent; and
  2. An applicant for a type S wastewater certificate must possess the same education and experience required for a regular wastewater certificate in the same class, except experience must have been gained in a wastewater treatment facility or type S facility and an applicant for an S-A type certificate must have been certified as an S-B or B facility operator for at least two years; or an applicant for a type S-B certificate must have been certified as an S-C or C facility operator for at least one year.

When a person applies for a certification exam to operate a facility, at least 50 percent of the experience required must have been obtained in a wastewater treatment facility. The other 50 percent may be obtained in a type S facility (collection) or a drinking water treatment system. The class of the facility or water system the applicant operated must not be more than one class below the class of certificate of the exam. One year of experience in the operation of a water supply system or wastewater treatment facility may be considered as equivalent to one year of high school. Experience which is substituted for education cannot also be used to satisfy the experience requirements.

One month credit towards experience may be given for the successful completion of 40 contact hours of correspondence courses or other courses, relating to wastewater treatment or water supply from an accredited institution in chemical, civil, environmental, mechanical, or sanitary engineering, or in the physical or biological sciences. In no event shall such education be substituted for experience so as to reduce the experience requirement to less than one year.

No, after passing the examination you will be notified by the Agency that you have passed and must submit the $23.00 certification fee to the Agency within 90 days to become certified. If the applicant fails to submit the fee within 90 days, the applicant must apply for re-examination.

A certificate expires every three years and must be renewed within 30 days after its expiration date. A person must submit a $23.00 non-refundable renewal fee, and documentation of training attended during that three year period. Fifty percent of the contact hours required for renewal must be in approved directly related wastewater operations training. The other 50 percent 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 for contact hour determination.

  • 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. Upon request, we can provide you with information identifying the topics of incorrect answers. This is intended as a guide to show you the areas in which you may want to focus your 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.