Plant Operator Trainee Jobs in Arizona (NOW HIRING)

Description/Duties Hiring Bonus: The Water Resources Department is excited to offer a hiring bonus for individuals newly hired as Water Resources Plant Operator I/II/III. New Water Resources Operator's may be eligible for a $3,500 incentive at the conclusion of Initial City Probation. To receive the bonus, an Operator must work as a Plant Operator for one year and receive a successful performance evaluation.

This recruitment will be used to fill current vacancies at a Wastewater Treatment plant at either the Operator I, II or III level; however, this recruitment will also be used to create a list to fill possible future vacancies at any level. Offering salary may be made above the minimum of the posted salary range for this position depending upon qualifications and experience. Employees may progress through the full salary range, subject to their successful performance and annual budget approval.

First review of applications will be Monday, April 27, 2026; then weekly thereafter until all vacancies are filled. Water Resources Plant Operator I ($55,831.78 - $76,472.86) A Water Resources Plant Operator I is responsible for learning how to operate and maintain the City of Mesa's wastewater treatment plants during an assigned shift with guidance from more experienced Operators. Duties may include: maintaining and operating plant equipment and the processes related to the treatment of wastewater; operating valves, gates, and pumps; adjusting flow rates and chemical feed rate; collecting samples and submitting for laboratory testing; monitoring control panels, gauges, and meters; maintaining written data on test results, gauges, and meter readings; checking chemical tank levels; mixing chemical solutions; operating laboratory equipment to perform chemical analysis; preparing written logs; and relaying operational information to coworkers

Incumbents in this class will work only on a shift where an Operator II or higher is present. An Operator I may provide general guidance to lower-level plant operators. An employee in this class is expected to use appropriate safety equipment and follow safety procedures in performing assignments.

Operator I's will be exposed to such job hazards as toxic chemicals, methane gas, chlorine gas, ozone, hydrogen sulfide, raw sewage, sludge, and adverse weather conditions. This class performs related duties as required. An employee in this class will learn to perform the full scope of a Water Resources Plant Operator II including learning to troubleshoot issues.

This class is distinguished from the Water Resources Plant Operator Trainee class by the ability to operate with more independence and troubleshoot operational issues while working on shifts with more experienced operators present; and distinguished from the Operator II class by working on a shift where an experienced operator is present, while the latter may work on a shift independently. The Water Resources Plant Operator I receives close-to-general supervision from a Water Resources Operator II or higher and direction from the Water Resources Plant Supervisor, who reviews the employee's work in progress through meetings and by the evaluation of results achieved. A Water Resources Plant Operator I will be eligible to progress to the Water Resources Plant Operator II class by noncompetitive promotion upon meeting the specific criteria-based promotion requirements of experience, performance, certification, and on the job training.

An incumbent who fails to complete the training and noncompetitive, criteria-based promotion within 15 months of hire into position may be transferred, demoted, or terminated. Employees in this class may be required to work rotating shifts. This class is FLSA nonexempt.

Water Resources Plant Operator II ($61,556.14 - 84,314.26) A Water Resources Plant Operator II performs journey-level work while learning to independently operate and maintain the City of Mesa's wastewater treatment plants during an assigned shift. Duties may include: maintaining and operating plant equipment and the processes related to the treatment of wastewater; operating valves, gates, and pumps; adjusting flow rates and chemical feed rate; collecting samples and submitting for laboratory testing; monitoring control panels, gauges, and meters; maintaining written data on test results, gauges, and meter readings; checking chemical tank levels; mixing chemical solutions; operating laboratory equipment to perform chemical analysis; preparing written logs; and relaying operational information to coworkers with minimal supervision. Incumbents in this class will work only on a shift where an Operator III or higher is present

As experience is gained and skill level increases, the intensity of supervision will gradually decrease. An Operator II provides training and assistance to lower-level plant operators. An employee in this class is expected to use appropriate safety equipment and follow safety procedures in performing assignments.

Operator II's will be exposed to such job hazards as toxic chemicals, methane gas, chlorine gas, ozone, hydrogen sulfide, raw sewage, sludge, and adverse weather conditions. This class performs related duties as required. Employees in this class will learn to perform the full scope of a Water Resources Plant Operator III including gaining the ability to operate the plant independently.

This class is distinguished from the Water Resources Plant Operator I class by being able to perform duties with minimal supervision and direction; and from the Water Resources Plant Operator III class by working on a shift where a more experienced operator is present. The Water Resources Plant Operator II receives close-to-general supervision from an Operator III or higher; and direction from the Water Resources Plant Supervisor, who reviews the employee's work in progress through meetings and by the evaluation of results achieved. A Water Resources Plant Operator II will be eligible to progress to the Water Resources Plant Operator III class by noncompetitive promotion upon meeting the specific criteria-based promotion requirements of experience, performance, certification, and on the job training.

An incumbent who fails to complete the training and noncompetitive, criteria-based promotion within 15 months of hire or promotion may be transferred, demoted, or terminated. Employees in this class may be required to work rotating shifts. This class is FLSA nonexempt.

Water Resources Plant Operator III ($67,885.17 - 92,983.49) A Water Resources Plant Operator III is responsible for managing the complex daily operations and maintenance of City of Mesa's wastewater treatment plants during an assigned shift. Duties include: analyzing trends and data; monitoring equipment and processes through all available means to include gauges, meters, and Supervisory Control and Data Acquisition (SCADA) inputs; documenting and reviewing ongoing plant process operations and maintenance issues; assisting in the formulation and implementation of procedural objectives and programs, optimizing day to day processes; economic utilization of materials and equipment; collecting and analyzing process samples using laboratory procedures; demonstrating thorough and complete documentation; and systematic reviewing of all process procedures and anomalies. Computer data entry and organization of information is essential

Incumbents receive occasional supervision, instruction, and assistance as new or unusual situations arise, and must be capable of independent, well-informed, technically correct decisions. A Water Resources Plant Operator III regularly provides training and assistance to lower-level plant operators. An employee in this class is expected to use appropriate safety equipment and follow safety procedures in performing assignments.

Employees will be exposed to job hazards such as toxic chemicals, methane gas, chlorine gas, ozone, hydrogen sulfide, raw sewage, sludge, and adverse weather conditions. This class performs related duties as required. A Water Resources Plant Operator III may be responsible for prioritizing activities between the different wastewater treatment facilities and systems in order to maintain proper facility operation and assist with day-to-day shift oversight, leadership, mentorship, and training to other operational staff; and may serve in a lead capacity in the absence of the Water Resources Plant Operator Lead.

This position assumes responsibility for plant operations while on assigned shift, weekends, or holidays. This class is distinguished from the Water Resources Plant Operator II class by being able to perform duties on all shifts with no supervision. The Water Resources Plant Operator III receives general supervision from an Operator Lead and direction from the Water Resources Plant Supervisor, who reviews the employee's work in progress through meetings and by the evaluation of results achieved.

An Operator III works rotating shifts (by assignment) and may be required to work at different plant locations. Employees are subject to stand-by or emergency call-out during off-duty hours. This class is FLSA nonexempt.

Please refer to the links below for the full job description and additional information regarding assignments, preferred qualifications, and essential functions. Qualifications & Requirements Employee Values: All employees of the City of Mesa are expected to uphold and exhibit the City's shared employee values of Knowledge, Respect, and Integrity. Water Resources Plant Operator I Minimum Requirements: Any combination of training, education, or experience equivalent to graduation from high school or GED.

Some (6 months - 1 year) experience in a wastewater treatment plant, wastewater collection systems, or closely related operation. Certification Requirements: Must possess a Grade I (or higher) Wastewater Treatment System Operator certification from the Arizona Department of Environmental Quality (ADEQ) or equivalent certification from another state through reciprocity with Arizona by application date. ADEQ Certification through reciprocity must be obtained within three months of hire or promotion.

Must obtain a Grade II Wastewater Treatment System Operator certification from ADEQ within 15 months of hire or promotion date. Shall be responsible for acquiring a minimum of 30 Professional Development Hours (PDHs) every three years to maintain ADEQ Certification. Water Resources Plant Operator II Minimum Requirements: Any combination of training, education, or experience equivalent to graduation from high school or GED.

Good (1 - 3 years) experience in a wastewater treatment plant, wastewater collection systems, or closely related operation with at least one (1) year as Water Resources Operator at a wastewater treatment plant. Certification Requirements: Must possess a Grade II (or higher) Wastewater Treatment System Operator certification from the Arizona Department of Environmental Quality (ADEQ) or equivalent certification from another state through reciprocity with Arizona by application date. ADEQ Certification through reciprocity must be obtained within three months of hire.

Must obtain a Grade III Wastewater Treatment System Operator certification from ADEQ within 15 months of hire or promotion date. Shall be responsible for acquiring a minimum of 30 Professional Development Hours (PDHs) every three years to maintain ADEQ Certification. Water Resources Plant Operator III Minimum Requirements: Any combination of training, education, or experience equivalent to graduation from high school or GED.

Considerable (3 - 5 years) as Water Resources Operator at a wastewater treatment plant OR 2 years as a City of Mesa Water Resources Plant Operator (Wastewater). Certification Requirements: Must possess a Grade III (or higher) Wastewater Treatment System Operator certification from the Arizona Department of Environmental Quality (ADEQ) or equivalent certification from another state through reciprocity with Arizona by application date. ADEQ Certification through reciprocity must be obtained within three months of hire.

Shall be responsible for acquiring a minimum of 30 Professional Development Hours (PDHs) every three years to maintain ADEQ Certification. Water Resources Plant Operator I, II and III Special Requirements. Must possess a valid Class D Arizona Driver's License by hire or promotion date.

Must meet the qualifications to wear a tight-fitting respirator by passing a medical evaluation in accordance with Code of Federal Regulations (CFR) 1910-134 by hire or promotion date and must maintain certification. Must obtain a 40-hour HazWoper Certification as per the Occupational Safety and Health Administration (OSHA) and must attend an annual HazWoper refresher course to maintain certification. Substance Abuse Testing.

Due to the safety and/or security sensitive nature of this classification, individuals shall be subject to pre-employment or pre-placement alcohol, drug and/or controlled substance testing as outlined in City policy and procedures. Link to Job Description https://apps.mesaaz.gov/jobdescriptions/Documents/JobDescriptions/cs4203.pdf https://apps.mesaaz.gov/jobdescriptions/Documents/JobDescriptions/cs4515.pdf https://apps.mesaaz.gov/jobdescriptions/Documents/JobDescriptions/cs5106.pdf