Kentucky Wastewater Treatment Operator Certification Practice Exam

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• Which device is used to grind solids to about 0.3 cm or smaller before treatment?
• Which mechanism adds oxygen to aerobic ponds during daylight?
• If 150 ppm BOD is removed, how much nitrogen and phosphorus are required based on the ideal ratio?
• Anaerobic bacteria are:
• Denitrification is the process by which bacteria convert nitrates into nitrogen gas, anoxic process.
• What are the three stages of standard anaerobic digestion?
• Which statement best describes young sludge in the activated sludge process?
• What characteristic is associated with peracetic acid disinfection?
• Three classifications of ponds?
• COD stands for which term?
• What are the chlorine (CL2) regulatory values and calibration frequency as given?
• Which influent scheme is described as long, conventional, high length and low width?
• Primary treatment is described as what process?
• What should be monitored to ensure screens operate effectively?
• Is there residual with UV?
• Major disadvantages to extended aeration?
• Which chemical is Peracetic Acid abbreviated as PAA?
• Which term defines the mean time bacteria spend in the activated sludge process?
• UV disinfection has residual?
• What plugs the space between the impeller and the casing?
• Where does the sludge primarily come from in this process?
• What do weirs measure in wastewater channels?
• Which term describes a condition that makes sludge float rather than settle?
• Which type of pump uses air to move wastewater?
• Which factor is not listed as an 'other factor' affecting activated sludge?
• Mean Cell Residence Time (MCRT) is defined as what?
• Which term describes bacteria converting nitrates to nitrogen gas?
• What is the monthly average limit for chlorine (CL2) in mg/L?
• What does preliminary treatment remove?
• Which term means a portion of a sample removed for testing?
• Rotating biological contactors (RBC) operate with what basic arrangement?
• How much oxygen per day per person is typically needed by the biological community in wastewater treatment (BOD concept)?
• What happens during endogenous respiration?
• Anaerobic digestion refers to:
• Which statement best describes an air lift pump?
• Name the three factors used to classify pumps.
• At what acid/alkalinity ratio does failure occur and pH drop?
• Which statement best describes algae?
• Coagulation and pH adjustment are often needed to treat which group?
• Grit removal general purpose?
• Chlorine is categorized as which pollutant type?
• Which industry is listed as a source of industrial wastewater?
• In anaerobic ponds, treatment depends on which conditions?
• The statement 'Sludge from the primary clarifier is removed only one time a day' is true.
• Phosphorus can be removed by which methods?
• Absorption is defined as which of the following?
• What is the ideal pH range for nitrification/denitrification processes?
• Which condition is not listed as a cause of filamentous growth?
• Normal treatment removes how many mg/L?
• For ammonia removal by denitrification, approximately how many pounds of O2 are required?
• Which term describes air lift?
• A solution that minimizes changes in pH when acids or bases are added.
• Which device is commonly used to measure electrical parameters in equipment?
• When clarifiers seem off, look for?
• Which class corresponds to a facility capacity of more than 7,500,000 gpd with 24 CEUs?
• The acid/alkalinity ratio during good digestion should be less than which value?
• In population loading calculations, which components are included?
• What is the monthly average limit for fecal coliform?
• Which of the following accurately lists the four most common disinfectants used in water treatment?
• Which item is commonly included on the label of a sample container?
• Organic overloading of an anaerobic digester will cause the pH to do what?
• Which statement describes respiration in cellular metabolism?
• Which statement best describes the advantage of composite samples over grab samples?
• An anaerobic process is described as:
• Which pond type is used in series after secondary treatment to provide tertiary treatment?
• Which of the following is not listed as a stage in the biological growth cycle?
• During the growth cycle, the population can double approximately every how long?
• What type of bacteria is used to feed on BOD in the activated sludge process?
• What is the primary clarifier?
• What is the goal for SOUR (Specific Oxygen Uptake Rate) in sludge?
• What does pH measure in a solution?
• Which statement best defines facultative bacteria?
• Which class corresponds to a facility capacity of 50,000 to 2,000,000 gpd with 12 CEUs?
• Bar screens remove what?
• What is the typical COD range mentioned for wastewater?
• What are disadvantages of aerobic digestion?
• Which statement is a design characteristic of an aerobic digester?
• Activated sludge consists of which organisms and what factors affect its performance?
• Which statement best defines an acid?
• Recirculation involves what action in wastewater treatment?
• Which term means the ability of water to buffer acids?
• What is the maximum monthly count for E. coli?
• Diffused-Air Aeration involves which mechanism?
• Which term describes sludge that floats rather than settles in secondary sewage treatment?
• UV light is what kind of radiation?
• Efficiency of trickling filter measured by?
• In an activated sludge system, settled sludge is typically what?
• Detritus is best described as heavy coarse grit in wastewater. Which option reflects that description?
• How many pounds per day per person of nitrogen are added?
• Which metric is commonly used to evaluate digestion effectiveness in terms solids reduction?
• Which pollutant is classified as conventional?
• What is a typical sludge age requirement for effective nitrification/denitrification?
• Which factors affect settling?
• NPDES stands for which of the following?
• Which method is used to mitigate inflow and infiltration in the collection system?
• What can be used to listen to a pump in operation?
• In anaerobic ponds, treatment depends on?
• What F/M ratio is listed as best?
• What is the preferred dissolved oxygen (DO) concentration range in the activated sludge process?
• What alkalinity is roughly required to convert 1 mg/L of ammonia to nitrate?
• Hydrogen sulfide (H2S) in wastewater is characterized by what?
• In the aeration tank of an activated sludge process, the mixture of activated sludge with primary effluent or raw wastewater and return sludge is called what, as long as it remains in the aeration tank?
• In extended aeration systems, the oxygen demand per pound of BOD removed is approximately how many pounds of O2?
• Polishing ponds provide which stage of treatment?
• Which term best describes nutrient enrichment leading to algal blooms in a body of water?
• A flow proportional sample is defined as:
• What is the daily maximum limit for chlorine (CL2) in mg/L?
• Which of the following is listed as an 'other factor' affecting activated sludge performance?
• Overfeeding SO2 causes DO?
• What is adsorption?
• Which parameter measures the oxygen required to break down the organic material in a given volume of water through aerobic biological activity?
• How are new cells produced in the activated sludge process?
• In an SBR cycle, which stage follows the Fill stage?
• During daytime photosynthesis, DO and pH will?
• Which pH range is considered best for wastewater treatment operation?
• The mass of bugs in the system is referred to as what?
• How many ppm alkalinity are required to convert 1 ppm nitrates to nitrogen?
• To what concentration does sludge in the primary clarifier settle?
• Which statement correctly defines adsorption and not absorption?
• What is the approximate phosphate production per person per day?
• In fixed film reactors, where do bacteria primarily grow?
• Which statement correctly describes the Kraus process in the activated sludge family?
• Recirculation in fixed-film reactors serves to?
• What are the two basic propeller pump types?
• In primary treatment, what is added to assist suspended solids in settling?
• Under the Clean Water Act, what is required to discharge pollutants into waters of the United States?
• Which statement about preserved samples is true?
• Which type of flume is most common for measuring flow?
• MLSS stands for which phrase?
• How does temperature affect nitrification rates according to the notes?
• Which temperature range is most commonly used for anaerobic digesters?
• Which statement describes a UV disadvantage?
• A time composite sample is defined as:
• Why is degassing necessary after ozone treatment?
• Device to separate substances by spinning them at high speed.
• Which pump type uses pneumatic injection to lift wastewater?
• Rising sludge in secondary clarifiers is usually a result of what process?
• Sludge age is defined as lbs MLSS in basin divided by lbs TSS influent. Which statement is true?
• Which of the following describes a step-feed influent scheme?
• Zoogloeal mass is best described as which of the following?
• How long does a sour digester typically take to recover?
• What best describes the operation of trickling filters?
• How should a weir be oriented relative to the flow axis to obtain accurate measurements?
• Total Suspended Solids (TSS) are measured by a test that assesses which of the following?
• Ozone is nonreactive and stable. TRUE FALSE
• Which pollutant category includes nitrogen and phosphorus?
• Which bacteria can grow with or without oxygen?
• The V-notch weir is particularly suited for measuring what type of flow?
• What is a key characteristic of sequential batch reactors (SBRs)?
• Which statement about lagoon maintenance is true?
• MLSS stands for what?
• What is the recommended dissolved oxygen range during nitrification/denitrification?
• What is the methane explosion range in air?
• Headworks may consist of which components?
• Which term describes the solids that settle out and form sludge in primary treatment?
• Anoxic conditions are defined as:
• What happens during the log phase of growth according to the notes?
• Which component provides a water seal connection in a pump packing?
• Which processes are considered suspended growth biological treatment methods?
• Ethics includes which of the following duties?
• Is UV harmful?
• The four common disinfectants listed include which combination?
• What is the maximum value in the breakpoint range for secondary wastewater?
• Ozone disinfects at about how many times faster than chlorine?
• Where does sludge go after concentration to 4-8%?
• Which statement describes the activated sludge process?
• Which type has an impeller?
• Which gas is listed as a toxic product of anaerobic digestion?
• Which of the following items are identified as must-know values for return activated sludge (RAS) operation?
• Which acid is used to preserve metal samples?
• What is the overall process that turns ammonia into nitrates and eventually nitrogen gas?
• What device is a circular grinder designed to grind the solids coming through the screen into pieces about 0.3 cm or smaller?
• Activated carbon is used in tertiary treatment with a detention time (DT) range of
• Flumes are used to measure flow in what type of channel?
• Which statement best describes the purpose of a composite sample?
• In fixed-film reactors, biomass growth occurs on the media or substrate.
• What is the minimum detention time (DT) required for chlorine disinfection?
• What is the minimum recommended dissolved oxygen concentration in the aeration basin?
• In the material, slime is described as what?
• For each 1 mg/L of nitrate-nitrogen denitrified to nitrogen gas, how much alkalinity is produced as calcium carbonate?
• A weir is defined as which of the following components used to calculate flow rate?
• Which statement about UV safety is true?
• Which of the following is a cause for reduced pump discharge?
• Dark, greasy-looking foam in the aeration basin is commonly associated with which condition?
• What is the sulfur dioxide IDHL value?
• How is O2 added to aerobic ponds?
• Which of the following describes a grab sample?
• Which item is NOT a suspended growth process?
• A wastewater operator with a facility capacity of less than 50,000 gpd and 12 continuing education units (CEUs) belongs to which class?
• Per person phosphorus addition in pounds per day is approximately:
• What is a defining characteristic of a sequence batch reactor (SBR)?
• Which grit removal type causes flow to spiral so grit settles?
• What is recommended when starting operation of ponds?
• Adsorption refers to which process?
• Two-stage digestion combines a standard-rate stage followed by a high-rate stage.
• In aerobic ponds, how is dissolved oxygen distributed?
• Sulfur dioxide is considered immediately dangerous at?
• At a detention time of 60 days, what removal efficiencies are typical?
• Which statement describes a disadvantage of aerobic digestion?
• What is the effect of a Low F/M ratio on sludge production?
• Which range represents the organic nitrogen content in wastewater?
• Open channel flow is characterized by the water surface being open to the atmosphere.
• In an aeration basin, what primarily controls the total suspended solids (TSS) concentration?
• Which is NOT listed as a factor affecting settling?
• Which statement about pH is correct?
• What is the reported flow per person per day?
• Which term refers to bacteria that do not require oxygen to survive?
• Which time frame is described for the BOD test in the notes?
• What is the stated goal regarding sludge and BOD removal?
• What plugs space between impeller and casing?
• Alkalinity is defined as:
• Supernatant is the term for which portion of the wastewater after solids have settled?
• Eutrophication refers to nutrient enrichment that leads to what?
• Which grit removal type uses air injection to create spiral flow?
• BOD stands for Biochemical Oxygen Demand.
• Which of the following is a chlorine derivative used for disinfection?
• Which of the following is NOT a common method for measuring wastewater flow?
• Which statement correctly defines ‘aerobes’?
• Which phosphate treatment scheme achieves the highest efficiency and also removes suspended solids?
• Which term is the biological wastewater treatment process accelerated by aeration?
• The simplest and least expensive flow measurement device is a?
• What are the typical discharge limits for phosphorus? (average and max)
• Which item on the sample container label helps identify when the sample was collected?
• Which acid/alkalinity ratio indicates the digester is stressed?
• According to the material, certificate renewal expires on which date?
• During good digestion, what is the typical alkalinity range?
• What is the primary purpose of weirs and flumes in wastewater flow measurement?
• Headworks may include components such as bar racks, comminutors, a wet well, and pumps. Which option lists the full combination commonly included at headworks?
• What is the proper nutrient ratio for carbon, nitrogen, and phosphorus?
• What is used to check air quality in the material?
• What is the total phosphorus range typically found in wastewater?
• What is the ideal nutrient ratio for carbon, nitrogen, and phosphorus in the given guidelines?
• Which unit is used for fecal coliform and E. coli counts in water samples?
• Lagoons require same daily inspections and maintenance?
• During settling, which items should be checked?
• Only the BOD required to remove carbon.
• In Kentucky, discharges are regulated under which system?
• What is the germicidal UV wavelength commonly used for disinfection?
• How many stages does anaerobic digestion have?
• What is considered the heart of the chlorinator?
• How much alkalinity is used per 1 lb of ammonia?
• In aerated lagoons, which items should be monitored daily?
• Total Suspended Solids are solids that:
• Which statement best distinguishes sludge age from MCRT?
• Freeboard is defined as what?
• Filamentous growth in activated sludge is usually caused by which condition?
• Which term describes the binding to a surface rather than absorption?
• In the population loading example, what is the influent volume?
• Which term refers to a solid product produced by wastewater treatment that can be recycled?
• MLSS is defined as what measurement in the aeration tank's mixed liquor?
• Which device is described as the simplest and least expensive flow measurement option?
• Which process results in solids settling out as sludge in a settling tank?
• In activated sludge operations, what is the effect of wasting more sludge?
• What is the main purpose of mechanical aeration?
• Which term best describes activated sludge?
• What are the detention times for standard-rate and high-rate anaerobic digestion?
• The notes indicate a chlorine dose of 9 ppm for each 1 ppm of ammonia. Which statement best describes this ratio?
• What provides water seal connection?
• What is the breakpoint range for secondary wastewater?
• What is the required oxygen content for the process described?
• Where on a pump curve is the Best Efficiency Point typically located?
• Base is defined as:
• How often is CL2 calibrated according to the limits?
• What is a sign of healthy biomass on rotating biological contactors?
• Which feature is associated with an oxidation ditch?
• DO concentration in the sludge process is typically maintained within which range?
• What distinguishes extended aeration from conventional activated sludge?
• What is the proper pH range for activated sludge operation?
• Which of the following is NOT listed as a pump type in the material?
• In pond detention time, which range indicates algae growth?
• What is sodium nitrate used for in ponds?
• Which type of bacteria is defined as requiring oxygen to grow?
• What is the recommended maximum sludge depth to prevent septic conditions?
• Which type of digester has the longest detention time (DT)?
• How much oxygen can 1 lb of algae growth produce?
• Compared to chlorine (Cl2), ozone disinfects at a faster rate.
• Which process decomposes waste under anaerobic conditions to produce biogas and a compost-like residue?
• Aeration is defined as which of the following?
• CEUs stands for what?
• List cycles of SBR.
• What is the purpose of CEUs in operator certification?
• Dissolved ozone requires degassing for about how long before discharge?
• Which of the following compounds is chlorine dioxide?
• In pump design, which component has an impeller?
• UV not effective in turbid water is a true statement. Which option best reflects this?
• In analytical testing, what describes the sample in which no analyte is added?
• Phosphorus removal in lagoon systems can be achieved by:
• In which season should MLSS be higher?
• Which term describes an oxygen-deficient condition (less than 0.5 ppm)?
• If the pounds of MLSS in the basin stay constant while pounds of TSS in the influent double, the sludge age will:
• A shock load is defined as what?
• Fry fish cannot tolerate more than which concentration of chlorine?
• A common drawback of extended aeration systems is what?
• Activated sludge typically has what percentage of microbes in the sludge?
• CBOD is defined as the portion of oxygen demand required to remove carbon.
• What describes fixed film or attached growth reactors?
• Formation and collapse of gas bubbles due to low pressure; can cause pitting and noise.
• Which of the following pairs correctly describes the oxygen requirement for each bacteria type used in activated sludge?
• Which nitrogen form is used as a parameter in wastewater analysis for nitrogen content?
• What preservative is added to samples to adjust the pH to less than 2?
• A composite sample is defined as what?
• What are the environmental and cost advantages of using peracetic acid (PAA) for disinfection?
• Which statement best describes aerobic digestion?
• What is the detention time (DT) for a primary clarifier?
• What is the daily maximum chlorine limit value in mg/L?
• Bacteria are defined as:
• What are the two basic types of flow channels?
• What is the desired dissolved oxygen (DO) level in aerobic ponds?
• Detritus is best described as which of the following?
• The point on a pump curve where efficiency is maximized is called what?
• What is the effect of operating at a very low F/M on sludge production?
• Which pollutant is NOT listed as conventional?
• What is the most common disinfectant used in water treatment?
• Do criminal and civil penalties exist for violations of wastewater regulations?
• Which term describes a solution that resists pH changes?
• Activated sludge is produced by which process?
• What operational action helps control TSS in an aeration basin?
• SOUR stands for which term?
• What is the typical sludge concentration before digestion?
• An aliquot is:
• What term describes chemicals used to cover unpleasant smells in wastewater facilities?
• Describe a step feed influent scheme.
• What are advantages of aerobic digestion?
• An Equalizing Basin serves what function?
• What is the typical hydraulic loading for activated carbon beds in gal/min per ft2?
• For deep cell facultative lagoons, what is the typical depth distribution?
• Flow meters should be read?
• In good digestion, volatile acids should be not more than which level?
• Which statement correctly differentiates absorption and adsorption?
• What does saturated mean in the context of dissolved oxygen in water?
• Grit removal protects pumps and pipes by removing grit that could cause wear. Which equipment is protected?
• Which gas is produced by anaerobic digestion and is toxic?
• How is organic loading defined for rotating biological contactors (RBCs)?
• What is considered the best acid/alkalinity ratio for digestion?
• Which statement about temperature effects in wastewater treatment is correct?
• Discharged phosphorus can cause eutrophication.
• Which flow measurement device uses the depth of flow to determine discharge?
• Digester covers can be which of the following?
• What are the three ways pumps are classified?
• What does TOC stand for and how is it measured?
• What is the principal mechanism by which activated carbon removes contaminants?
• Which is a design characteristic used to evaluate an aerobic digester's performance?
• Which flow measurement device is commonly described as the most common type for flow measurement?
• At what volatile acid to alkalinity ratio does an anaerobic digester become stressed?
• What is the CL2 IDHL value?
• Which statement best describes anaerobic ponds?
• Which statement best describes chlorine disinfection efficiency relative to pH?
• Which of the following is a pump type?
• Industrial wastewater treatment often uses which steps?
• What is the nitrogen population equivalent value per day?
• Which term refers to a primarily organic solid product produced by wastewater treatment processes that can be beneficially recycled?
• Diffusion refers to which process in the context of oxygen in water?
• Denitrification occurs under what conditions and DO range?
• Which entity administers the NPDES program at the federal level?
• Conservative pollutants in wastewater are generally characterized by?
• Disinfection of water by the addition of small amounts of chlorine or a chlorine compound.
• Ponding on trickling filters occurs when voids become plugged, reducing water passage. This is typically due to which condition?
• Which statement best describes a facultative pond?
• Which class corresponds to a facility capacity of 2,000,000 to 7,500,000 gpd with 24 CEUs?
• Which statement describes facultative bacteria?
• Which phenomenon can occur when rapid pressure changes near a pump or valve cause gas bubbles to form and collapse, possibly producing noise?
• Which activated sludge treatment type uses a short-term contact tank followed by a clarifier, with return sludge going to a stabilization tank?
• Which term refers to the total mass of organisms in a given area or volume?
• Zoogloeal mass is most typically observed in which unit process?
• Absorption refers to which process in the notes?
• A baffle is best described as:
• Which temperature range corresponds to mesophilic bacteria?
• Whole effluent toxicity belongs to which pollutant category?
• What dissolved oxygen concentration range is generally required for microorganisms in wastewater treatment?
• New cells are produced through which process?
• Slug loads refer to
• An instantaneous grab sample is typically described as:
• Which set of stages is listed as part of the biological growth cycle?
• In the notes, what does the F/M ratio measure?
• Chlorine disinfection is most effective at what pH level?
• Which statement best describes BOD in the notes?
• Which of the following is a cause for noisy pumps?
• Which statement best describes the Parshall flume?
• At 180 days DT, what removals are typical?
• Which flow measurement method uses a float to determine flow rate?
• Why control scum on lagoon?
• In the context of BOD testing, what does synthesis refer to?
• Advanced waste treatment is defined as which?
• For every 100 ppm of BOD removed, how much nitrogen and phosphorus are required?
• What gas is primarily produced in anaerobic digestion?
• Two-stage anaerobic digestion involves which sequence?
• What is the typical range of biochemical oxygen demand (BOD) in wastewater?