Kentucky Wastewater Treatment Operator Certification Practice Exam

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