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99 Cards in this Set
- Front
- Back
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What is the most common reason for waste water to contain intermittent large ammounts of sand, gravel, and grit?
A) groundwater infiltration B) storm events C) cement company dischargees D)refinery discharges |
B) Storm events |
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Combined waste water is defined as
A) domestic waste water and industrial B) sanitary wastewater C) domestic wastewater and storm runoff D) sanitary wastewater and storm runoff |
D) sanitary wastewater and storm runoff |
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In general, the solids content in wastewater is about
A) 0.1% B) 0.6% C) 1% D) 2.5% |
A) 0.1% |
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Generally, the percentage of dissolved solids in the amount of total solids is about
A) 30% B) 35% C) 45% D) 55% |
A) 30% |
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Generally, the percentage of dissolved solids in the amount of total solids is about
A) 45% B) 55% C) 65% D) 70% |
D) 70% |
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Which type of organisms would most probably be associated with poor treatment or young biomass?
A) amoebas B) free-swimming ciliates C) rotifers D) stalked ciliates |
A) amoebas |
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Which type of organisms would most probably be associated with very clean plant effluent, low BOD, and low amounts of suspended solids?
A) free-swimming ciliates B) stalked ciliates C) amoebas D) rotifers |
B) stalked ciliates |
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Aerobic bacteria will reproduce and live in an environment that contains only
A) Hydrogen sulfide B) oxygen C) water D) methane |
B) oxygen |
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Anaerobic bacteria will reproduce and live only in an environment that completely lacks
A) free or dissolved nitrates B) dissolved methane C) dissolved hydrogen sulfide D) free or dissolved oxygen (DO) |
D) free or dissolved oxygen |
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The biochemical oxygen demand (BOD) test usually has a specific time of
A) 2 days B) 3 days C) 4 days D) 5 days |
C) 5 days |
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An Imhoff cone meassures
A) volume of settleable solids B) how fast sludge water will filter through a membrane C) depth of transparency in a digester D) sludge carry-over from a digester |
A) volume of settleable solids |
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Septic conditions are cause by
A) fungi B) molds C) anerobic conditions D) hydrogen sulfide accumulation |
C) anerobic conditions |
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Scum is usually removed in the ________ treatment stage.
A) primary B) secondary C) biological D) chemical |
A) primary |
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When domestic wastewater enters natural waters, what species deplete most of the oxygen?
A) anerobic bacteria B) aerobic bacteria C) protozoanz D) rotifers |
B) aerobic bacteria |
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Once the oxygen is depleted in a natural body of water, which organisms take over?
A) flagellates B) sporozoans C) anaerobic bacteria D) coliform bacteria |
C) anaerobic bacteria |
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The major gas produced by anaerobic decomposition is
A) methane B) carbon dioxide C) nitrogen D) hydrogen sulfide |
A) methane |
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Another name for primary treatment is
A) chemical treatment B) sedimentation C) grit removal D) biological treatment |
B) sedimentaion |
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Digester gas is __________ when mixed with air in the proper proportions
A) extremely toxic and moderately explosive B) extremely explosive C) slightly toxic and explosive D) slightly explosive when there is an ignition source |
B) extremely explosive |
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A pond that has an aerobic top layer and an anaerobic bottom layer is called
A) an oxidation pond B) a faculatative pond C) a waste stabilization D) a decomposition pond |
B) faculatative pond |
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A pond that is used to treat raw wastewater is called
A) an oxidation pond B) a faculatative pond C) a waste stabilization D) a decomposition pond |
C) a waste stabilization pond |
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What is the angle of the bars on a manually cleaned bar screen?
A) 25 degree B) 30 degree C) 33 degree D) 45 degree |
B) 30 degree |
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What is the angle on the bars on a mechanically cleaned cleaned bar screen?
A) 30 to 45 degree B) 40 to 45 degree C) 45 to 60 degree D) 50 to 60 degree |
C) 45 to 60 |
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What is the ideal wastewater velocity in feet per second (ft/s) through a screen
A) 0.5 ft/s B) 1.0 ft/s C) 1.5 ft/s D) 2.0 ft/s |
C) 1.5 ft/s |
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What is the ideal wastewater velocity in ft/s for grit removal in a grit chamber?
A) 0.7 ft/s B) 1.0 ft/s C) 1.2 ft/s D) 1.4 ft/s |
B) 1.0 ft/s |
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In general, what is the water content screened material?
A) 50% B) 65% C) 80% D) 89% |
C) 80% |
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What is the wastewater velocity range in ft/s for grit removal in a grit chamber
A) 0.5 to 1,0 ft/s B) 0.7 to 1.4 ft/s C) 0.8 to 1.5 ft/s D) 1.0 to 1.5 ft/s |
B) 0.7 to 1.4 ft/s |
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Which one of the following chemicals gives water its greatest capacity to neutralize acids?
A) hydroxide B) silicate C) borate D) phosphate |
A) Hydroxide |
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The bar rack is used
A) when the bar screen is out of service B) before the bar screen C) after the bar screen D) either before or after the bar screen |
A) when the bar screen is out of service |
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Typically, what is the average detention time for a wastewater in a primary clarifier?
A) 2 hr B) 3 hr C) 3.5 hr D) 4.5 hr |
A) 2 hr |
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Which one of the following gasses is irritating to the eyes
A) carbon dioxide B) chlorine C) methane D) hydrogen sulfide |
B) chlorine |
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Activated sludge clarifiers accept material to be settled from
A) an aeration tank B) a primary clarifier C) a trickling filter D) a primary digester tank |
A) an aeration tank |
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According to the Clean Water Act, secondary treatment is defined as a wastewater plant producing an effluent that has no more than ____ total suspended solids and no more ______ BOD.
A) 20 mg/L, 40 mg/L B) 30 mg/L, 30 mg/L C) 40 mg/L, 40 mg/L |
B) 30 mg/L, 30 mg/L |
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The color of the biofilm on a rotating biological contactor would appear ______ under normal operating conditions.
A) dark green B) greenish gray C) gray D) brown |
C) gray |
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A primary effluent and returned activated sludge mixture is called
A) mixed liquor B) mixed liquor susspended solids C) activated sludge mixture D) waste activated sludge |
D) waste activated sludge |
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The mixture of organisms and solids in water that is removed from the settling tank is called
A) mixed liquor B) mixed liquor suspended solids C) activated sludge liquor D) mixed activated sludge
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A) mixed liquor |
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Under normal operating conditions, what color is activated sludge
A) dark chocolate brown B) light to medium brown C) greenish brown D) dark green |
A) dark chocolate brown |
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What test(s) could an operator use to make a process change immediately if a problem develops?
A) BOD test B) chemical oxygen demand test (COD) C) sludge volume index (SVI) test D) food-to-organism (F/M) ratio and percent volatile matter |
B) chemical oxygen demand (COD) test |
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The main "workers" in the activated sludge are
A) bacteria B) protozoans C) ciliates D) rotifers |
A) bacteria |
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A yellow gas flame from a digester's waste gas burner may indicate a poor quality gas with a
A) high CO2 content B) high H2S content C) high H2S and CO2 content D) high H2S and skatole |
A) high CO2 content |
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Ponds used in series after primary wastewater treatment are sometimes called
A) secondary treatment ponds B) tertiary ponds C) oxidation ponds D) polishing ponds |
C) oxidation ponds |
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The most common type of pond is
A) an anaerobic B) an aerobic C) a faculatative pond D) an oxidation pond |
C) a faculative pond |
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Which one of the following nuisance organisms is controlled simply by the water surface being disturbed by wind or currents
A) mosquitoes B) shrimp-like animals C) dragonfly larvae D) chironmid midges |
A) mosquitoes |
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When is dissolved oxygen in a waste pond the lowest
A) sunrise B) sunset C) around noon D) around 4:00 PM |
A) sunrise |
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What would be the most likely solution, if the influent to a wastewater treatment plant had an H2S odor?
A) airstream treatment B) add treatment chemicals C) remove sludge faster D) improve houes keeping |
B) add treatment chemicals |
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What is the main reason why wastewater treatment plants remove phosphorus from their effluent before discharging to a lake or river?
A) because it seriously depletes oxygen B) because if forms phosphoric acid that is detrimental to fish C) to reduce bacteria that can kill aquatic wildlife D) to reduce the growth |
D) to reduce the growth of algae |
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What is the color of liquid chlorine?
A) yellow B) yellowish green C) green D) amber |
D) amber |
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How many times heavier than air is chlorine gas?
A) 1.95 times B) 2.0 times C) 2.5 times D) 2.7 times |
C) 2.5 times |
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Free available chlorine consists of
A) hypochlorous acid and hypochlorite ion B) hypochlorous acid, dissolved chlorine gas, and dichloramine C) dissolved chlorine gas and hypochlorite acid D) dissolved chlorine gas, hypochlours acid, and hypochlorite ion. |
D) dissolved chlorine gas, hypochlours acid, and hypochlorite ion |
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The fusible plug on a chlorine cylinder will start to melt at approximately
A) 145º F B) 150º F C) 155º F D) 160º F |
D) 160º |
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This solids treatment method usually has 20 days of retention time:
A) lime stabilization B) aerobic digestion C) gravity thickening D) thermal treatment |
B) aerobic digestion |
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This solids treatment method processes solid in a sealed unit:
A) gravity thickening B) solids concentrators C) lime stabilizations D) anaerobic digestion |
D) anaerobic digestion q |
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This solids treatment method produces methane gas that can be used in other plant processes:
A) aerobic digestions B) anaerobic digestion C) chlorine oxidation D) thermal treatment |
B) anaerobic digestion |
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This solids treatment method cures the final product and then it may be applied to farmlands:
A) solids concentrators B) composting C) anaerobic digestion D) flotation thickening |
B) composting |
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This solids treatment method uses evaporation but also requires a great deal of labor:
A) sand drying beds B) thermal treatment C) gravity treatment D) inceneration |
A) sand drying beds |
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This solids treatment method uses a partially submerged rotating drum:
A) centrifuge B) vacuum filter C) solids concentrators D) aerobic digestion |
B) vacuum filter |
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These solid treatment methods use coagulant polymer and pressure:
A) solids concentrators B) centrifuges C) vacuum filters D) belt filter and plate |
D) belt filter and plate |
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Test such as pH, temperature, and dissolved oxygen should always be performed within _____ after collection.
A) 15 min B) 30 min C) 1 hr D) 2 hr |
A) 15 min |
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When calibrating a pH meter, the buffers used should bracket the expected pH and
A) be no more than 2 pH units apart B) be at least 2 pH units apart C) be at least 3 pH units apart, such as 4,7, and 10 D) be no more than 3 pH units apart |
B) be at least 2 pH units apart |
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A test method for determening dissolved oxygen is the
A) iodometric direct titration B) azide modification of the winkler titration method C) amperometric direct titration D) Odzakovic titration method |
B) azide modification of the winkler titration method |
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How long can a dissolved oxygen sample wait for analysis using the modified Winkler method, if it is preserved with sulfuric acid?
A) 2 hr B) 4 hr C) 6 hr D) 8 hr |
D) 8 hr |
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BOD samples can be preserved by
A) freezing B) storing them in a refrigerator above freezing and up to 4ºC C) adding 3 mL of 0.2N HNO3 D) adding 2 mL of 0.2N H2SO4 |
B) storing them in a refrigerator above freezing and up to 4ºC |
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The maximum holding time for preserved BOD samples is
A) 2 days B) 3 days C) 4 days D) 5 days |
A) 2 days |
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Which one of the following tests is least likely to effectively help an operator control a plants process?
A) DO B) pH C) temperature D) BOD 5 |
D) BOD 5 |
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The maximum holding time for a preserved total suspended solids sample is
A) 2 days B) 3 days C) 5 days D) 7 days |
D) 7 days |
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Generally, the state regulatory body must be notified of all unusual or extraordinary discharges by telephone within
A) 1 hr B) 2 hr C) 24 hr D) 48 hr |
C) 24 hr |
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Generally, the state regulatory body must be notified for any non compliance that could adversely affect that state waters or that could endanger public health within
A) 1 hr B) 2 hr C) 8 hr D) 24 hr |
D) 24 hr |
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Electromotive force (emf) is also known as
A) voltage B) ohms C) watts D) amps |
A) voltage |
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Electron flow is measured in
A) watts B) ohms C) amps D) voltage |
C) amps |
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What type of fuses would most likely be used to protect a meter?
A) current-limiting B) dual-element C) phase fuses D) voltage sensitive |
B) dual-element |
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What class of fire involves electrical equipment?
A) class A B) class B C) class C D) class D |
C) class C |
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When a permit is required to enter a confined space, who may sign the permit?
A) sttending person B) entrant C) entry supervisor D) Occupational Safety and Health Administration (OSHA) representative |
C) entry supervisor |
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Which one of the following is a measure of a materials opposition to the flow of electric current?
A) volts B) ohms C) ampers D) watts |
B) ohms |
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What class of fire involves oil and grease?
A) class A B) class B C) class C |
B) class B |
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Why is it essential to ventilate a valve vault before entry?
A) equalize temperature and pressure B) eliminate foul odors C) remove excessive moisture D) remove dangerous gases |
D) remove dangerous gases |
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The primary purpose of check valves is to prevent
A) loss of prime B) excessive pump pressure C) water from flowing in two directions D) water hammer |
C) water from flowing in two directions |
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Which one of the following infectious diseases is not transmitted via wastewater?
A) tetnaus B) tuberculosis C) the acquired immune deficiency syndrome (AIDS) virus D) polio |
C) the acquired immune deficiency syndrome (AIDS) virus |
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Which one of the following gasses is least likely to collect in a below ground vault?
A) hydrogen sulfide B) gasoline vapors C) carbon dioxide D) carbon monoxide |
D) carbon monoxide |
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When working in a manhole, your vehicle, whenever possible, should be placed
A) on the right side of the man hole B) on the left side of the man hole C) ahead of the manhole and oncoming traffic D) between the manhole and oncoming traffic |
D) between manhole and oncoming traffic |
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OSHA requires that adequate protection, such as shoring, be placed in any trench that is
A) 3.5 ft or greater in depth B) 4 ft or greater in depth C) 4.5 ft or greater in depth D) 5 ft or greater in depth |
D) 5 ft or greater in depth |
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How far back from the opening of a trench should soil excavated from that trench be placed?
A) 1 ft at least B) 2 ft at least C) 3 ft at least D) 4 ft at least |
B) 2 ft at least |
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In a trench, ladders are required every
A) 10 ft B) 20 ft C) 25 ft D) 30 ft |
C) 25 ft |
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How many ladders are required to be in a 5 ft deep trench when six people are working down in the trench?
A) one ladder B) two ladders C) three ladders D) six ladders |
D) six ladders |
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If some clothes are on fire, what class of fire is it
A) Class A B) Class B C) Class C D) Class D |
A) Class A |
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Which of the following is not an essential ingredient
A) ignition source B) fuel C) heat D) oxygen |
A) ignition source |
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If some magnesium is on fire, what type of fire is it?
A) class A B) class B C) class C D) class D |
D) class D |
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What is the minimum number of people that should be on-site working at a confined space site, where one of them is entering a manhole?
A) two B) three C) four D) five |
B) three |
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What type of fire extinguishers should be in pump stations?
A) foam B) carbon dioxide C) A-B-C chemical type D) water and carbon dioxide |
C) A-B-C chemical type |
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What piece of laboratory glassware is primarily used to mix chemicals and measure approximate volumes?
A) pipette B) beaker C) burette D) graduated cylinder |
B) beaker |
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The electrical potential between two points is measured in
A) amperes B) volts C) ohms D) watts |
B) volts |
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What is the most common use today for a positive-displacement pump?
A) lift or booster pump B) chemical feed pump C) filter feed pump D) wastewater water intake pump |
B) chemical feed pump |
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Which laboratory glassware will give the most accurate measurement of liquids?
A) graduated cylinders B) beakers C) flasks D) burettes |
D) burettes |
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Which laboratory glassware is used for measuring volumes?
A) flasks B) beakers C) graduated cylinders D) burettes |
C) graduated cylinders |
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People working in and around wastewater must be immunized for
A) tetanus B) cholera C) amebiasis D) dysentery |
A) tetanus |
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Which one of the following laboratory tests has a zero holding time?
A) nitrate B) chlorine residual C) turbidity D) BOD 5 |
B) chlorine residual |
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Which one of the following statements concerning colloids is false?
A) solutes have a greater effect on freezing and boiling points of liquids than do colloids B) only very small colloids will pass through a semipermeable membrane C) the average wavelength of white light is smaller than the dimensions of colloidal particles D) dialysis is the separation of colloids from solutes through a semipermeable membrane |
D) dialysis is the separation of colloids from solutes through a semipermeable membrane |
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Which one of the following statements concerning colloids is true?
A) an ion opposite in charge to a colloidal particle will force its way into the colloidal particle B) electrolytes will stabilize colloids C) van der waal's forces help stabilize colloidal particles D) electrophoresis is a term used to describe the settling of a colloid in an electrical field |
A) an ion opposite in charge to a colloidal particle will force its way into the colloidal particle |
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Water is used as a standard because it has unique properties and it is readily available in its pure state. Which standard is not correct?
A) celcius scale B) the calorie C) the kilogram D) specific gravity |
C) the kilogram |
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What acids are formed when water reacts with nonmetal oxides?
A) acid hydroxide B) acid anhydrides C) acid oxides D) acid hydrates |
B) acid anhydrides |
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Which one of the following is not a hydrate?
A) alum B) blue stone C) sodium nitrate D) ferrous sulfate |
C) sodium nitrate |
