Operator Certification & Licensing
Water & Wastewater Certification

What is a Certified Operator?

A "certified operator" is an individual who has met the requirements of ch. NR 114, Wis. Adm. Code[PDF exit DNR], and has been issued a certificate by the DNR to operate one or more of the classifications of waterworks or wastewater treatment plants.

Exams

Written certification exams are held twice a year at six locations (one in each DNR region). Registration is required before taking a written exam. Applications for the exams can be requested through your regional certification coordinator anytime after the last exam and up to 5 weeks prior to the next exam date.

The application must be postmarked at least 28 days prior to the scheduled exam date. Any exam applications postmarked after the due date will be returned and the applicant will not be able to participate in the exam.

A score of 75% or higher is a passing score on each exam. Any exam that you pass will be credited to your record. You will receive notice of your exam scores by mail approximately 3-4 weeks after the exam date. The letter sent out after each exam to notify you of the score you received includes a list of missed objectives on the right hand side of the letter. Look up the missed objectives in your study guide for the appropriate subclass to determine what areas of the test you got wrong. Examination papers will not be returned to you. If you need a study guide for any of the exams they can be found below or call your regional coordinator.

Applicants who have failed a written exam may apply for re-examination at the next scheduled exam by requesting an application and paying exam fees.

Wastewater Operators

Wastewater treatment plants are assigned class codes from 1 to 4, with 4 being the highest class and 1 being the lowest class. This plant class is based on a number of factors, including plant design flow, the number of treatment processes, permit effluent limits, and types of industries contributing wastewater. Subclasses are also assigned to wastewater treatment plants that correspond to the processes used at the plant.

To become a certified wastewater operator for subclasses A through J you must pass an introductory or advanced general written exam and introductory or advanced subclass written exam. To become certified in subclass K and L, no general exam is required. To help you study for the exams, study guides are available below for each subclass exam. Study guides are a valuable tool.

Subclasses are designated by letters A through L. Each plant must have a designated operator-in-charge certified at the plant class level and in the same subclasses as the processes used at the plant. Wastewater operators have the opportunity to take certification exams for the following general processes:

You may take the general and subclass exams at either grade level (exam skipping). You will be given credit for having passed the introductory level subclass exams if you pass the advanced level subclass exams. (Example: You wrote the Primary Settling Advanced exam and passed, you will be given credit for having passed the Primary Settling Introductory exam.)

When you have passed a general and subclass exam (or K or L exam) you will become an Operator-In-Training - Grade T.

In order to move above a Grade T you must have earned at least 1 year experience and have filled out a Wastewater Operator Certification Experience Form [PDF] and submitted the completed sheet to your regional coordinator.

The region will determine whether experience credit is approved or denied and you will be notified either way. Experience sheets are available from your regional coordinator at any time of the year.

The requirements for wastewater operator certification for each grade is:

1. Grade T
   Pass written introductory or advanced general exam and introductory or advanced subclass exam(s).
2. Grades 1 & 2
   Pass written introductory or advanced general exam and introductory or advanced subclass exam(s) and have one year of subclass specific experience for Grade 1; 2 years of experience for Grade 2.
3. Grades 3 & 4
   Pass written advanced general exam and advanced subclass exam(s) and have 3 years of experience for Grade 3; 4 years of experience for Grade 4.
4. Subclass K (Special K) & L (Electroplating and Metal Finishing) will have one exam that covers all grade levels. No general exam is required for these two subclasses.

NOTE: All operators who passed Grade 1 exams before October 1, 1995 will have to pass the introductory or advanced exams to become Grade 2, and operators who have passed Grade 3 exams will have to pass the advanced exams to attain Grade 4, in addition to having the required experience.

Each plant must have a designated operator in charge certified in the appropriate subclasses for the processes used at the plant.

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Waterworks Operator

All publicly owned waterworks are required to have a certified operator and are assigned a Grade of 1. Waterworks subclasses correspond to the processes used and are assigned letters as follows:

The requirements for waterworks operator certification for each grade are:

1. Grade T
   Passing waterworks subclass exam(s).

2. Grade 1
   One year of satisfactory experience in the operation of a waterworks plant subclass(es), and passing the appropriate subclass exam(s).

   You must have filled out a Waterworks Operator Certification Experience Form [PDF] and submitted the completed sheet to your regional coordinator.

   The region will determine whether experience credit is approved or denied and you will be notified either way. Experience sheets are available from your regional coordinator at any time of the year.

3. Class S waterworks facilities shall have an operator certified at Grade T or 1 on duty at all times of operation.

Each plant must have a designated operator in charge certified in the appropriate subclasses for the processes used at the plant.

Contact

For more information or questions on the water & wastewater operator certification program, please contact your regional coordinator.

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