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NR 114.50 NR 114.50Purpose. The purpose of this subchapter is to establish rules for the certification of wastewater treatment plant operators pursuant to s. 281.17 (3), Stats.
NR 114.50 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15.
NR 114.51 NR 114.51Applicability. The provisions of this subchapter are applicable to all owners and operators of wastewater treatment plants as defined in this subchapter and under the coverage of a WPDES permit.
NR 114.51 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15.
NR 114.52 NR 114.52Definitions. In this subchapter:
NR 114.52(1) (1)“Advanced coursework" means education that is beyond the basic knowledge of a particular aspect of wastewater treatment. It concentrates advanced wastewater studies in only a few subjects in blocks of a minimum of 20, 40, 60, or 80 hours. Technical talks or presentations at meetings, single- or part-day classes, or training sessions, seminars, or conferences are not included in this definition.
NR 114.52(2) (2)“Associates degree" means a wastewater treatment related degree earned at a 2-year technical college.
NR 114.52(3) (3)“Certificate" means a printed document issued by the department, pursuant to this subchapter, stating that the operator named therein has met the competency requirements for one or more operator levels and subclasses.
NR 114.52(4) (4)“Certified operator" means a person who has meet the requirements of this subchapter and has been issued a certificate by the department to work at a given level and subclasses of wastewater treatment plants.
NR 114.52(5) (5)“Department" means the department of natural resources.
NR 114.52(6) (6)“Direct responsible charge" means having responsibility for providing on-site technical direction in the operations of a wastewater treatment plant.
NR 114.52(7) (7)“Experience" means the daily hands-on operation and maintenance of a wastewater treatment plant as provided in pars. (a), (b), and (c). Treatment plant managers providing daily on-site technical supervision of the operator or operators performing those tasks may be eligible for claiming experience.
NR 114.52(7)(a) (a) The first twelve months of claimed experience shall be subclass specific.
NR 114.52(7)(b) (b) Subsequent months of claimed experience may be any general wastewater operational experience.
NR 114.52(7)(c) (c) One year of experience is based on full-time employment at a treatment plant or 1,000 hours of cumulative experience, over a minimum of 12 months, for part-time operators.
NR 114.52(8) (8)“Graduate degree" means an advanced degree, M.S. or Ph.D., from an accredited college or university with graduate studies and emphasis in wastewater treatment or water pollution control engineering.
NR 114.52(9) (9)“Health and safety training" means classes relating to wastewater treatment plant operations and maintenance and includes but not limited to confined space, excavation, hearing conservation, water safety, blood-borne pathogens, CPR — First Aid, mechanical and electrical safety, fall protection, hazardous plant chemicals as well as others.
NR 114.52(10) (10)“Industrial wastewater treatment plant" means a privately owned wastewater treatment plant for treating liquid wastes resulting from any process of industry, manufacture, trade, or business or the development of any natural resources.
NR 114.52(11) (11)“Level" means the basic or advanced classification assigned to a wastewater treatment plant operator pursuant to this subchapter.
NR 114.52(12) (12)“Major contributing industry" means an industrial or commercial facility that is a user of a municipally owned wastewater treatment plant, and has a waste which the department determines has, or may have, a significant impact, either singly or in combination with other wastes, on a wastewater treatment plant or on the quality of effluent from a wastewater treatment plant.
NR 114.52(13) (13)“Mechanical plant" means a plant that is designed and constructed with a series of steel or concrete basins using pumps, pipes, and other equipment to actively convey and treat wastewater. Pond, lagoon, or natural systems are not part of this definition.
NR 114.52(14) (14)“Operate" means to be in direct responsible charge of a subclass or subclasses of operations at a wastewater treatment plant and a sanitary sewage collection system.
NR 114.52(15) (15)“Operator-in-charge" means the person designated by the owner of the wastewater treatment plant to be in direct responsible charge of a subclass of operations of a treatment plant or of a sanitary sewage collection system and involved in hands-on day-to-day operations.
NR 114.52(16) (16)“Owner" means the state, county, town, sanitary district, city, village, metropolitan sewerage district, corporation, firm, company, institution, association, utility district, school district, sewerage commission, or individual owning or operating a WPDES permitted wastewater treatment plant.
NR 114.52(17) (17)“Satellite sewage collection system" means a municipally owned or private sewage collection system that conveys wastewater to another sewerage system which provides the wastewater treatment.
NR 114.52(18) (18)“Sanitary sewage collection system" means the common sanitary sewers, interceptor sewers, pump stations and supporting equipment in a community that receive wastewater from buildings and conveys it to a wastewater treatment plant.
NR 114.52(19) (19)“Subclass" means a letter assigned a treatment plant based upon a particular type of treatment process at the plant and to the letter assigned to a person based on passing a subclass examination for a specific operational process.
NR 114.52(20) (20)“Tertiary phosphorus removal" means the advanced physical and chemical removal of phosphorus to achieve very low phosphorus concentrations not achievable by conventional methods.
NR 114.52(21) (21)“Undergraduate degree" means a Bachelor's degree earned at a 4-year accredited college or university in which at least 240 hours were wastewater treatment related.
NR 114.52(22) (22)“Wastewater treatment plant" means a facility that provides for the treatment of sanitary or industrial wastewater or both. The following types of facilities are excluded from operator certification:
NR 114.52(22)(a) (a) Facilities defined as private sewage systems in s. 145.01 (12), Stats.
NR 114.52(22)(b) (b) Pretreatment facilities which discharge to a public sewer system for treatment.
NR 114.52(22)(c) (c) Industrial wastewater treatment which consists solely of a land disposal system.
NR 114.52(22)(d) (d) Digesters at agricultural operations that reuse, recycle or landspread the treated wastes.
NR 114.52(22)(e) (e) Concentrated aquatic production facilities (fish hatcheries) in which no biological treatment process is utilized.
NR 114.52(23) (23)“WPDES permit" means a permit issued to a publicly owned treatment plant under s. 283.31, Stats., for the purposes of controlling pollutant discharge.
NR 114.52 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15; correction in (7) (intro.) made under s. 35.17, Stats., Register June 2014 No. 702.
NR 114.53 NR 114.53General requirements.
NR 114.53(1)(1)Every WPDES permitted treatment plant shall have a designated operator-in-charge holding a current and valid certificate pursuant to this subchapter. The designated operator-in-charge shall be certified at the level and in all subclasses of the treatment plant, except laboratory. Treatment plant owners shall notify the department of any changes in the operator-in-charge within 30 days.
NR 114.53(2) (2)Owners of treatment plants, which includes both the treatment plant and sanitary sewage collection system to it, shall have a designated collection system operator-in-charge for sanitary sewage collection systems. The designated operator-in-charge shall have passed and be certified in the sanitary sewage collection system subclass. For owners of satellite sanitary sewage collections systems, collection system operator certification is voluntary.
NR 114.53(3) (3)All wastewater treatment plants holding a WPDES permit that have a registered or certified laboratory shall have at least one operator that works in the laboratory certified at the basic level in the laboratory subclass.
NR 114.53(4) (4)Upon a change in a wastewater treatment plant's classifications caused by the addition of a new subclass listed in s. NR 114.56 (4), the operator-in-charge shall have 12 months to pass the necessary subclass examinations and to gain the one year of subclass specific experience.
NR 114.53(5) (5)Upon a change in a wastewater treatment plant's level of operations from basic to advanced, the operator-in-charge shall have 36 months to obtain advanced certification, provided the person is making earnest efforts towards advanced certification and that the treatment plant is in compliance with all terms and conditions of its WPDES permit.
NR 114.53(6) (6)Owners of basic wastewater treatment plants, in the event of the unexpected loss of the operator-in-charge, may designate an operator-in-training certified in all subclasses of the plant as the operator-in-charge for a period up to twelve months.
NR 114.53(7) (7)Owners of advanced wastewater treatment plants, in the event of the unexpected loss of the designated operator-in-charge, shall ensure the continued proper operation and maintenance of the treatment plant by another advanced certified operator in all subclasses of the plant.
NR 114.53 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15.
NR 114.54 NR 114.54Examinations and applications.
NR 114.54(1)(1)Examinations, education, and on-the-job experience shall be used to determine knowledge, skill, and the ability of the applicant to perform duties at a wastewater treatment plant. A score of 75 percent or higher shall be a passing score on each examination. An applicant desiring to be certified to perform duties at a wastewater treatment plant shall submit a completed exam application to the department. The department shall approve or deny the application within 10 business days of receipt of the application, unless the application involves a revoked or suspended certificate, in which case, the department shall approve or deny the application within 35 business days of receipt of the application. Fees as listed under s. NR 114.55 shall accompany the application.
NR 114.54 Note Note: The application form is available on the following website: or by writing to the Department of Natural Resources, Operator Certification Program, PO Box 7921, Madison, WI 53707-7921.
NR 114.54(2) (2)The department will primarily rely on an organization under contract with the department to provide examinations. The department may conduct examinations on a case-by-case basis when necessary to accommodate applicants' needs. An organization under contract to provide examinations may charge fees to cover the cost of providing any exam under this section as allowed under its contract with the department.
NR 114.54 Note Note: The special U subclass exam will only be a written exam conducted by the department on an as needed basis for examinees with approved applications.
NR 114.54(3) (3)Basic examinations shall consist of 25 to 50 questions specific to the subclass. The wastewater treatment plant advanced examination shall consist of 100 questions with content from all subclasses.
NR 114.54(5) (5)Examination results shall be made available to an applicant within 30 days of the examination date.
NR 114.54(6) (6)An applicant who fails to pass an examination may apply to the department for reexamination.
NR 114.54(7) (7)The department shall provide study guides pertaining to each subclass.
NR 114.54(8) (8)A wastewater treatment plant operator shall take and successfully complete the general wastewater examination and subclass examinations to become an operator-in-training in each subclass.
NR 114.54(9) (9)A wastewater treatment plant operator shall take and successfully complete the requirements of sub. (8) and meet one-year subclass-specific experience to become a basic level operator in a subclass.
NR 114.54(10) (10)A wastewater treatment plant operator may take the wastewater treatment advanced certification examination to earn four points towards advanced certification according to the table in s. NR 114.57 (1) (c).
NR 114.54 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15; EmR2123: am. (1), r. and recr. (2), r. (4), am. (5), (6), eff. 8-21-21; CR 21-068: am. (1), r. and recr. (2), r. (4), am. (5), (6) Register April 2022 No. 796, eff. 5-1-22.
NR 114.55 NR 114.55Fees.
NR 114.55(1)(1)Fees for certification shall be as follows:
NR 114.55(1)(a) (a) Each basic examination     $ 25.00
NR 114.55(1)(b) (b) Advanced examination     $ 50.00
NR 114.55(1)(c) (c) Advanced certification application   $100.00
NR 114.55(1)(d) (d) Certification renewal     $ 45.00
NR 114.55(1)(e) (e) Late renewal penalty     $ 25.00
NR 114.55(1)(f) (f) Reciprocity application     $100.00
NR 114.55(1)(g) (g) A 3rd-party organization may charge additional fees to administer an online exam.
NR 114.55(2) (2)Fees shall accompany completed application forms. Fees are non-refundable.
NR 114.55(3) (3)Certifications shall be renewed every 3 years. The renewal fee is due no later than the expiration date of the certificate. A late renewal penalty fee shall be assessed for any renewal application postmarked after the expiration date.
NR 114.55(4) (4)A veteran may request a fee waiver for a first-time license or operator certificate in accordance with the veterans fee waiver program under s. 45.44, Stats.
NR 114.55 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15. EmR2123: emerg. cr. (1) (g), (4), eff. 8-21-21; CR 21-068: cr. (1) (g), (4) Register April 2022 No. 796, eff. 5-1-22; correction in (1) (g) made under s. 35.17, Stats., Register April 2022 No. 796.
NR 114.56 NR 114.56Classification of wastewater treatment plants.
NR 114.56(1)(1)Each wastewater treatment plant shall be assigned a basic or advanced rating. An advanced wastewater treatment plant is one that meets any one of the following criteria:
NR 114.56(1)(a) (a) Is a mechanical plant with an annual average design flow greater than 1.0 MGD.
NR 114.56(1)(b) (b) Has a biochemical oxygen demand (BOD) limit of 10 mg/L or less.
NR 114.56(1)(c) (c) Has surface water limits for total phosphorus or total nitrogen and utilizes a biological nutrient removal process.
NR 114.56(1)(d) (d) Uses a tertiary phosphorus removal process to achieve ultralow phosphorus limits.
NR 114.56(1)(e) (e) Is a municipal treatment plant that receives wastewater from a major contributing industry.
NR 114.56(1)(f) (f) Is a municipal treatment plant that produces Class A biosolids.
NR 114.56(2) (2)Wastewater treatment plants that do not meet any of the criteria in s. NR 114.56 (1) shall be classified as a basic facility.
NR 114.56(3) (3)Wastewater treatment plants that utilize special or unique biological, physical, chemical, or other unique treatment methods shall have an operator certified in subclass U.
NR 114.56(4) (4)Thirteen wastewater treatment plant subclasses are established in Table 1.
Table 1
Wastewater Treatment Plant Categories and Subclasses - See PDF for table PDF
NR 114.56 History History: CR 13-054: cr. Register June 2014 No. 702, eff. 7-1-15.
NR 114.57 NR 114.57Qualifications and level of wastewater treatment plant operators.
NR 114.57(1)(1)Two levels and 13 subclasses of wastewater treatment plant operators are established. Operator subclasses are the same as plant subclasses listed in Table 1. To qualify for certification at a given level and subclass, a person shall meet the appropriate examination, education and experience requirements.
NR 114.57(1)(a) (a) Operator-in-training. To qualify for operator-in-training in a specific subclass, a person shall pass the basic general wastewater examination and a basic subclass examination.
Published under s. 35.93, Stats. Updated on the first day of each month. Entire code is always current. The Register date on each page is the date the chapter was last published.