Kentucky Wastewater Treatment Operator Certification Practice Exam

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