Operator Master
Level 1 · EntryLevel 2 · IntermediatePractice ExamMath CenterCoursesAbout
Start Practicing
Operator Master

Free exam practice for wastewater treatment operators.

AccountSettingsAboutSupportPrivacyTermsExam Disclaimer

Appearance

Operator Master is independent and is not affiliated with WPI, PSI, ABC, the Washington State Department of Ecology or any other state or provincial certification agency.

New Jersey wastewater operators

How to Become a Wastewater Operator in New Jersey

The steps from no license to a New Jersey S-1 wastewater treatment or C-1 collection license, how to apply to NJDEP and take the exam at PSI, how to keep your license active and what operators earn. Every requirement links to a New Jersey Department of Environmental Protection (NJDEP) document or its licensing rule, N.J.A.C. 7:10A.

NJDEP makes the final eligibility determination. Check with NJDEP before you apply.

Why it matters

Who Needs a License?

New Jersey's rule requires every owner of a public wastewater treatment system or public wastewater collection system to employ a licensed operator holding the license NJDEP sets for that system's class. The licensed operator is in charge of running the system.

Class 3 and Class 4 treatment systems must have a full-time licensed operator, unless NJDEP grants an exemption for an automated system.

Some systems do not need a licensed operator, such as wastewater treatment systems that do not need a New Jersey Pollutant Discharge Elimination System (NJPDES) permit or general permit authorization to discharge.

When a licensed operator changes jobs, the operator and the system owner must tell NJDEP using the Licensed Operator in Charge Employment Notification Form (DEP-065).

New Jersey issues S licenses to operate public wastewater treatment systems and C licenses to operate public wastewater collection systems, each in Classes 1 to 4. N licenses cover industrial wastewater treatment systems, and T, W and VSWS licenses cover drinking water systems.

NJDEP classifies each wastewater treatment plant by points for its size and processes, such as design flow, secondary treatment, solids handling and disinfection. S-1 plants score 30 points or less, S-2 plants 31 to 55, S-3 plants 56 to 75 and S-4 plants 76 or more.

Collection systems are classified by the population they serve: C-1 serves 251 to 1,500 people, C-2 1,501 to 15,000, C-3 15,001 to 50,000 and C-4 50,001 or more.

Sources
  • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
  • Examination Application for License to Operate, Section II: Education and Experience (ADM-035, 2/2021)
  • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)
  1. Step 1

    Take the Required Training Course

    Every license class needs an NJDEP-approved training course before you apply for the exam. For S-1 and C-1, that is the Introduction to Water and Wastewater course.

    Class 2, 3 and 4 licenses need an advanced course: Advanced Wastewater for S licenses and Advanced Collections for C licenses.

    Sacramento State correspondence courses are approved alternatives. For S-1 that is Operation of Wastewater Treatment Plants Volume I, and for C-1 Operation and Maintenance of Wastewater Collection Systems Volume I. These are not online courses; the materials are bought from Sacramento State.

    NJDEP publishes the textbooks approved for each course, from Sacramento State and the Water Environment Federation (WEF).

    Sources
    • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
    • Examination Application for License to Operate: Checklist (forms dated 2/2021)
    • Approved Water and Wastewater Operator Textbooks (June 2026)
    • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)
  2. Step 2

    Build Your Operating Experience

    S-1 and C-1 need a high school diploma or equivalency certificate and one year of operating experience. Operating experience is time spent doing operational duties at a system, as accepted by NJDEP's Board of Examiners.

    Class 3 and 4 licenses also need direct responsible charge experience: active, daily, on-site supervision, including operation and maintenance, at a system no more than one class lower than the license you want, while holding a license no more than one grade lower.

    Your experience must be verified on a Statement of Qualifications (Form ADM-035A), signed by the licensed operator in charge at each facility where you worked. If you work for a contract operations firm, list each facility, not just the firm.

    You need enough documented experience in each area for each exam you take. If you do both treatment and collection work in the same job, show the share of your time spent on each.

    Sources
    • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
    • Examination Application for License to Operate, Section II: Education and Experience (ADM-035, 2/2021)
    • Examination Application for License to Operate, Section III: Statement of Qualifications (ADM-035A, 2/2021)
  3. Step 3

    Apply to NJDEP for the Exam

    Apply with NJDEP's Examination Application for License to Operate (Form ADM-035) and the Statement of Qualifications (Form ADM-035A). Include proof of your highest education and a copy of your course certificate.

    Each license type needs its own application and a nonrefundable $70 application fee. Applications without the right documents or fee are returned without review.

    NJDEP's Board of Examiners reviews each application to decide whether you may take the exam. Give an email address you check often; an application without one is rejected.

    The 2/2021 application checklist says to email the application to operatorexams@dep.nj.gov and mail the signed form with the fee. Check NJDEP's licensing page for the current way to apply before you send anything.

    Open NJDEP's Licensing PageRead NJDEP's Licensed Operator FAQ
    Sources
    • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
    • Examination Application for License to Operate: Checklist (forms dated 2/2021)
    • Examination Application for License to Operate (ADM-035, 12/19)
    • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)
  4. Step 4

    Schedule Your Exam With PSI

    Since January 6, 2023, New Jersey's exams are given at PSI testing centers instead of by remote proctoring. You can test at a PSI center in New Jersey or anywhere in PSI's U.S. network.

    PSI charges its own testing fee, separate from NJDEP's application fee. Check NJDEP's licensing page for the current amount.

    Source
    • Attention NJ Water/Wastewater Licensing Exam Applicants and Exam Candidates (exams at testing centers from January 6, 2023)
  5. Step 5

    Get Your License

    When you pass the exam and pay the initial license fee, NJDEP issues the license of the class you were tested for.

    Sources
    • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
    • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)
  6. Step 6

    Keep Your License Active

    Licenses run to September 30 and are renewed every year. NJDEP sends renewal invoices each August, and you can pay online through DEP Online under Pay for a License.

    If you do not renew within one year after the renewal date, you must meet the current requirements and pass a new exam before you can be licensed again.

    You also need Training Contact Hours (TCHs) in fixed three-year cycles: 18 for Class 1 and 2 licenses (up to 6 in safety) and 36 for Class 3 and 4 licenses (up to 12 in safety). A new licensee does not need TCHs until the next full cycle.

    Only wastewater-related courses count for wastewater licenses. NJDEP-approved courses count, IACET continuing education units count at 1 CEU = 10 TCHs, and related college courses count at 15 TCHs per credit hour.

    Passing an exam in your field earns 7 TCHs. A Red Cross first aid or CPR class earns 3, and New Jersey Water Environment Association (NJWEA) membership earns 1 a year for wastewater licenses, up to 3 a cycle.

    Sources
    • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
    • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)

Exam day

What the Exam Is Like

New Jersey uses WPI (formerly ABC) exams, given at PSI testing centers.

At the testing center you get an on-screen calculator and a formula table, and the formula table is also given to you on paper.

You may bring a basic calculator without graphing or alphanumeric functions, and PSI can provide one if you need it.

If you fail the same exam three times, you must retake and complete the NJDEP-approved training course for that license before a fourth try.

Operator Master has free practice questions with an explanation after every answer, a timed full-length practice exam and step-by-step math help built on the WPI formula table. It is an independent study tool, not the official exam.

Start Level 1 · Entry PracticeFree Sample QuestionsMath Formulas
Sources
  • Attention NJ Water/Wastewater Licensing Exam Applicants and Exam Candidates (exams at testing centers from January 6, 2023)
  • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)

Pay

What Operators Earn in New Jersey

The median pay for water and wastewater treatment plant and system operators in New Jersey was $78,760 a year ($37.87 an hour) in 2025, compared with $60,020 nationally. One in ten earned $51,050 or less, and one in ten earned $99,240 or more.

Median Pay by Area

Atlantic City-Hammonton
$65,300 a year
New York-Newark-Jersey City (NY-NJ)
$83,320 a year
Philadelphia-Camden-Wilmington (PA-NJ-DE-MD)
$66,680 a year
Trenton-Princeton
$63,130 a year
Vineland
$80,040 a year

These federal figures cover drinking water and wastewater operators together, at every class. Pay for a new operator is usually nearer the low end.

Source
  • New Jersey Wages for Water and Wastewater Operators (BLS 2025 data)

Moving up

Experience Needed for Each Class

Class S-1 or C-1

Experience with a high school diploma
1 year of operating experience

Class S-2 or C-2

Experience with a high school diploma
3 years of operating experience

Class S-3 or C-3

Experience with a high school diploma
6 years: 3 years of operating experience and 3 years of direct responsible charge

Class S-4 or C-4

Experience with a high school diploma
10 years: 6 years of operating experience and 4 years of direct responsible charge

Every class also needs the NJDEP-approved training course for that class and a passing exam. An associate's or bachelor's degree shortens the experience from Class 2 up: for example, S-2 or C-2 needs 2 years with an associate's degree or 1.5 years with a bachelor's degree. Direct responsible charge means daily on-site supervision while holding a license no more than one grade lower.

Sources
  • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
  • N.J.A.C. 7:10A, Licensing of Water Supply and Wastewater Treatment System Operators (courtesy copy, amendments through December 2008)

From another state

Already Certified Somewhere Else?

If you hold a license from another state, you can apply to NJDEP's Board of Examiners for an equivalent New Jersey license. You must meet New Jersey's education and experience requirements and have passed an exam considered equivalent to New Jersey's.

New Jersey grants reciprocity only for licenses from states that grant reciprocity to New Jersey licensees. Apply on the exam application, with a copy of your valid out-of-state license; Class 3 and 4 applicants must also document direct responsible charge experience.

Sources
  • Water Supply & Wastewater Treatment System Operators Licensing: Frequently Asked Questions (2021)
  • Examination Application for License to Operate, Section III: Statement of Qualifications (ADM-035A, 2/2021)
  • Examination Application for License to Operate (ADM-035, 12/19)
NJDEP Water and Wastewater System Operator Licensingoperatorexams@dep.nj.gov609-292-2957

Last source review: 2026-09-28. Rules and fees can change; confirm important decisions with NJDEP. Operator Master is independent and is not affiliated with NJDEP, WPI, ABC or PSI.