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CWEA ECI Grade 2 practice questions

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About the CWEA ECI Grade 2 exam

The CWEA Environmental Compliance Inspector (ECI) exams are for people working or who want to work as Environmental Compliance Inspectors in California.

The exams are run by the California Water Environmental Association (CWEA), an organization for wastewater professionals in California.

The CWEA ECI exams has four grades: Grade 1, Grade 2, Grade 3, and Grade 4. Grade 1 is the easiest exam and is for entry-level positions. Grade 2 is more difficult and is for supervisor positions. Grade 3 is more difficult still and for middle-management positions. Grade 4 is the hardest exam and is for upper-management positions.

While CWEA certification isn't mandatory for a job as an Environmental Compliance Inspector, it can help you get a job and it can also lead to a pay raise and other benefits.

Practice questions

1) What is 0.05 mL in microliters?
  1. 0.0005 μL
  2. 0.005 μL
  3. 5 μL
  4. 50 μL
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2) Complete this lime softening reaction: Ca(HCO₃)₂ + Ca(OH)₂ -> _______ + 2H₂
  1. 2CaCO₂
  2. 2CaCO₃
  3. CaCO₂
  4. CaCO₃
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3) How many milliliters of 0.1718 M potassium hydroxide are needed to titrate 25 mL of 0.1932 M citric acid?
  1. 0.83 mL
  2. 1.71 mL
  3. 22.23 mL
  4. 28.12 mL
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4) 100 mL of a 0.05 N sulfuric acid solution neutralizes 500 mL of a NaOH solution. Calculate the normality of the NaOH solution.
  1. 0.006
  2. 0.01
  3. 1.05
  4. 1.4
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5) How many mL of a 0.2 M KOH solution will neutralize 15 mL of 0.4 M HCl?
  1. 10 mL
  2. 20 mL
  3. 30 mL
  4. 40 mL
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6) How many liters of 0.2 M potassium hydroxide are needed to neutralize 25,000 liters of 0.8 M citric acid?
  1. 25,000
  2. 50,000
  3. 75,000
  4. 100,000
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7) During an eight-hour shift, an employee is exposed to zinc oxide fumes at a concentration of 150 ppm for two hours, 75 ppm for another two hours, and 50 ppm for four hours. Calculate the 8-hour time-weighted average.
  1. 81.25 ppm
  2. 88.515 ppm
  3. 91.75 ppm
  4. 95 ppm
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8) Which of these is written information that must be supplied by manufacturers of chemicals and hazardous materials?
  1. OSHA
  2. OSM
  3. SDS
  4. TOSM
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9) Which section of a safety data sheet gives the flammability of a chemical?
  1. Accidental release measures
  2. Handling and storage
  3. Physical and chemical properties
  4. Transport information
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10) Who is responsible for preparing safety data sheets?
  1. The customer
  2. The end-user
  3. The government
  4. The manufacturer
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11) On the NFPA hazard diamond below, what do the letters SA mean?
  1. Can shock and/or cause acid damage
  2. Safety assessed
  3. Simple asphyxiant
  4. Substance abuse
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12) What is NH₃ more commonly known as?
  1. Ammonia
  2. Benzene
  3. Hydrazine
  4. Nitrogen hydroxide
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13) A pH of 9 is how many times more alkaline than a pH of 7?
  1. 2
  2. 3
  3. 10
  4. 100
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14) Primary treatment of wastewater typically removes what percentage of total suspended solids?
  1. 0–10%
  2. 20–40%
  3. 50–70%
  4. 80–100%
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15) If a 100 mL sample of sludge contains 800 mg of solids, then what is the sludge index number of the sample?
  1. 0.008
  2. 0.125
  3. 125
  4. 8
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16) What is flocculation?
  1. The biochemical decomposition of organic matter
  2. The process of bringing a liquid into contact with air
  3. The process of particles joining together to form larger particles
  4. The separation of liquids from solids
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17) In the context of wastewater treatment, what does the abbreviation IU stand for?
  1. Incoming undercurrent
  2. Industrial user
  3. Intelligent user
  4. Intermediate user
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18) Which of these is a physical wastewater treatment method?
  1. Ion exchange
  2. Neutralization
  3. Oxidation
  4. Screening
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19) Which chemical is added to raw wastewater to make dirt particles stick together and coagulate?
  1. Alum
  2. Chloramine
  3. Hypochlorite
  4. Ozone
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20) What is the final step of SARS-CoV-2 wastewater testing?
  1. RNA extraction
  2. RNA measurement
  3. Sample concentration
  4. Sample preparation
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21) UV disinfection happens at what stage of wastewater treatment?
  1. Primary
  2. Secondary
  3. Tertiary
  4. Quaternary
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22) What is the sedimentation step of wastewater treatment also known as?
  1. Clarification
  2. Flocculation
  3. Rapid gravity filtration
  4. Slow sand filtration
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23) If chlorine is used for water disinfection, then the sewage treatment plant will require a sample measurement of:
  1. chlorinating granules
  2. fecal coliform
  3. total residual chlorine
  4. total suspended solids
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24) When testing wastewater samples for viruses, what is used to estimate the amount of virus lost during sample processing?
  1. Matrix recovery control
  2. Phage recovery control
  3. TDS recovery control
  4. Virus recovery control
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25) Which of the following methods of wastewater treatment uses specially modified soil to remove microorganisms and extra nutrients from effluent?
  1. Absorption trenches
  2. Amended soil mounds
  3. Sand mounds
  4. Subsurface irrigation
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26) Which emerging technology uses microorganisms to generate electricity from the organic matter in wastewater?
  1. Membrane technology
  2. Microalgae
  3. Microbial fuel cells
  4. Restriction fragment length
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27) If a vertical cylindrical tank has a diameter of 5 feet and a height of 8 feet, then what is the capacity of the tank in cubic feet?
  1. 145
  2. 157
  3. 227
  4. 290
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28) During the initial stages of water treatment, water mixes gently to form heavier and larger particles called:
  1. clogs
  2. clusters
  3. flocs
  4. sediments
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29) A well has a one-meter diameter and its water is ten meters deep. How much water is in the well?
  1. 385 liters
  2. 2,730 liters
  3. 4,890 liters
  4. 7,850 liters
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30) A river has a flow rate of 50 cubic feet per second. Calculate its flow rate in gallons per second.
  1. 39
  2. 92
  3. 198
  4. 374
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31) Which of these is the preferred way to prevent pollution?
  1. Recycling
  2. Source reduction
  3. Waste disposal
  4. Waste treatment
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32) What does an orifice plate measure?
  1. Flow rate
  2. Salinity
  3. pH
  4. Temperature
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33) An industry discharges 5,000 gallons of wastewater per day. The wastewater contains 10 mg/L of magnesium. What is the industry's mass emission rate of magnesium in pounds per day?
  1. 0.31 pounds per day
  2. 0.42 pounds per day
  3. 0.58 pounds per day
  4. 0.64 pounds per day
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34) Which industry typically produces runoff high in nitrogen?
  1. Agriculture
  2. Metal plating
  3. Petrochemical
  4. Textiles
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35) Which of these water treatment methods is a chemical treatment process?
  1. Activated sludge
  2. Filtration
  3. Neutralization
  4. Trickling filter
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36) What is the best method to determine the chemicals that industrial dischargers are placing in the collection system?
  1. Field test kits
  2. Laboratory chemical analyzes
  3. Results of industrial self-monitoring
  4. Visual observations
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37) Which of these is a variable the Manning formula requires to calculate the flow rate in a pipe?
  1. BOD of the water
  2. Hydraulic radius
  3. Length of the pipe
  4. Runoff coefficient
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38) What is the purpose of an unannounced industrial inspection?
  1. To check effluent quality
  2. To meet with POTW's normal contact person
  3. To review paper work
  4. To test response of industry
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39) Which of the following is a recoverable chemical from textile mill waste?
  1. Caustic soda
  2. Soda ash
  3. Sulfur dioxide
  4. Sulfuric acid
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40) What does the term buffer capacity mean?
  1. A measure of how much a solution or liquid can neutralize acids or bases
  2. A solution that resists change in pH from the addition of acid or base
  3. The amount of liquid a solid material can absorb
  4. The flow or load that a treatment plant is designed to handle
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41) A district charges a sewer impact fee of $2,500 per REC (Residential Equivalent Connection) for new developments, where one REC is 150 gallons per day. Calculate the sewer impact fee for a new office building with 15 employees, assuming each employee will use 20 gallons of water per day.
  1. $2,175
  2. $2,875
  3. $3,000
  4. $5,000
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42) A developer anticipates that a new site will use 1,100 gallons of water per day. The sewer impact fee is $29.81 per gallon per day. Calculate the total daily sewer impact fee.
  1. $28,198
  2. $29,100
  3. $32,791
  4. $34,814
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43) Which of the following Acts regulates pollutant discharges into water and regulates the quality standards for surface waters?
  1. Clean Water Act
  2. Comprehensive Environmental Response, Compensation, and Liability Act
  3. National Environmental Policy Act
  4. Safe Drinking Water Act
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44) Hydraulic load is the height in inches of the average volume of wastewater introduced into a pond in one:
  1. second
  2. minute
  3. hour
  4. day
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45) For protection from effluent splashes and flying debris, workers should use:
  1. fall-detection technology
  2. flame-resistant clothing
  3. respiratory equipment
  4. safety goggles
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46) Typically, how often do facilities have to submit discharge monitoring reports (DMRs)?
  1. Weekly
  2. Monthly
  3. Bi-annually
  4. Annually
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47) Which of these is a conventional pollutant?
  1. Benzene
  2. Biochemical oxygen demand
  3. Cyanide
  4. Hexavalent chromium
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48) Which of these should you never do around a UV system?
  1. Collect samples
  2. Drink bottled water
  3. Look into the lamps without eye protection
  4. Plug a UV system into a grounded electrical outlet
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49) What are receiving water standards based on?
  1. Categorical standards
  2. Technology-based standards
  3. The best available technology economically achievable
  4. The tolerance of the stream to pollutants
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50) A factory uses 3 cubic feet of copper daily. Assuming the factory operates five days a week, calculate the number of gallons of copper the industry uses every week, to the nearest gallon.
  1. 22
  2. 73
  3. 112
  4. 157
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51) Which law provides increased protection for groundwater systems susceptible to fecal contamination?
  1. Ground Water Rule
  2. Hydraulic Fracturing Law
  3. Source Water Protection
  4. The Underground Injection Control Program
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52) A primary clarifier is 120 feet long, 40 feet wide, and 14 feet deep. The influent flow is 7.5 MGD. Calculate the detention time in hours.
  1. 1.6 hours
  2. 3.2 hours
  3. 4.8 hours
  4. 6.2 hours
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53) Which federal program authorizes the President to take emergency action in the event of the release of hazardous substances into the environment?
  1. Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)
  2. Environmental Change and Security Program (ECSP)
  3. National Environmental Policy Act (NEPA)
  4. Resource Conservation and Recovery Act (RCRA)
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54) What is brownwater?
  1. Water from sinks, showers, bathtubs, and washing machines
  2. Water that contains soil
  3. Water that has been cleaned at a water treatment plant
  4. Water that has come into contact with feces
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55) The provisions of 40 CFR part 433 subpart A apply to six metal finishing operations. Which of the following is one of these operations?
  1. Electrochemical machining
  2. Electron beam machining
  3. Printed circuit board manufacture
  4. Vapor plating
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56) Algal bloom is mostly caused by the presence of large amounts of what in water?
  1. Carbon dioxide
  2. Nitrogen and phosphorus
  3. Plastic
  4. Suspended matter
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57) In traffic control, which taper requires the longest distance?
  1. Downstream
  2. Merging
  3. Shifting
  4. Shoulder
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58) A representative sample is:
  1. collected during minimum flows
  2. obtained when industrial representatives are present
  3. similar to the larger body of wastestream being sampled
  4. transported to a laboratory for analysis
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59) Which organization administers the Manual on Uniform Traffic Control Devices (MUTCD)?
  1. Environmental Protection Agency (EPA)
  2. Federal Highway Administration (FHWA)
  3. Federal Motor Carrier Safety Administration (FMCSA)
  4. National Transportation Safety Board (NTSB)
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60) A battery manufacturing industry discharges 4,000 kg of wastewater per day carrying 6 g/L of benzene. How many kilograms of benzene does the industry discharge per day?
  1. 20 kg
  2. 24 kg
  3. 28 kg
  4. 32 kg
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61) A solution of hydrogen peroxide contains 20% hydrogen peroxide and has a density of 2 g/mL. How many grams of hydrogen peroxide are in one liter of the solution?
  1. 100 g/L
  2. 200 g/L
  3. 300 g/L
  4. 400 g/L
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62) Why would a water sample be collected in a septum vial?
  1. To keep the sample cool
  2. To prevent air from contaminating the sample
  3. To prevent people from tampering with the sample
  4. To prevent people handling the sample from getting infected by possible pathogens
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63) What is the difference between point-source pollution and non-point-source pollution?
  1. Point-source pollution comes from a single place while non-point-source pollution comes from many places
  2. Point-source pollution is characterized by continuous discharges while non-point-source pollution occurs in sudden, concentrated releases
  3. Point-source pollution is mainly associated with agricultural runoff while non-point-source pollution is linked to industrial discharges
  4. Point-source pollution results from natural processes while non-point-source pollution results from human activities
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64) Which method of pollution treatment uses fungi to clean up pollution?
  1. Mycoremediation
  2. Phytotransformation
  3. Rhizodegradation
  4. Rhizofiltration
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65) Which of the following bacteria is an indicator of water pollution?
  1. Azospirillum
  2. Biggiata
  3. E.coli
  4. Lactobacillus
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66) What is the main toxic metal found in dental amalgam?
  1. Aluminum
  2. Chromium
  3. Lead
  4. Mercury
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67) When taking a water sample from a plastic spigot, what is the easiest and most effective way to disinfect the spigot?
  1. Alcohol swab
  2. Flame
  3. Ozone disinfection
  4. Peracetic acid immersion
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68) New Sources have how many days to submit a baseline report to the Control Authority before commencing discharge?
  1. 90 days
  2. 180 days
  3. 270 days
  4. 360 days
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69) A tank holds 10,000 gallons of cyanide solution with a cyanide concentration of 20 mg/L. Calculate the number of pounds of cyanide in the tank.
  1. 0.84
  2. 1.67
  3. 2.32
  4. 3.84
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70) What is the formula for calculating the response factor in gas chromatography?
  1. Response factor = concentration / detector response
  2. Response factor = mass / slope of the plot
  3. Response factor = mass / volume
  4. Response factor = peak area / concentration
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71) Which term means the movement of water through soil or other porous materials?
  1. Percolation
  2. Precipitation
  3. Reticulation
  4. Sedimentation
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72) What is the primary goal when attending to a spill?
  1. Keep people safe
  2. Minimize damage to machinery
  3. Minimize damage to the environment
  4. Prevent the spill from spreading
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73) An industry has three sewer connections with the following discharge rates: 1) 500 gpd, 2) 150 gpd, 3) 350 gpd. A flow-weighted composite sample of 3 liters is needed. How many milliliters of sample from each connection should be composited?
  1. 1000, 1000, 1000
  2. 1200, 800, 1000
  3. 1500, 450, 1050
  4. 500, 150, 350
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74) If a water sample is not properly chilled and sealed, which of these water quality indicators would stay the same?
  1. BOD
  2. COD
  3. Dissolved sulfide
  4. Hardness
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75) Which type of Resource Conservation and Recovery Act (RCRA) waste code applies to wastes from nonspecific sources?
  1. F
  2. K
  3. P
  4. U
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76) Composite samples measure:
  1. pollutants of specific concern
  2. the average amount of pollutants
  3. the maximum concentration of pollutants
  4. the pollutant discharge at specific time
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77) How is the flow depth measured in a Palmer-Bowlus flume?
  1. Channel bottom to water surface at measure point
  2. Channel bottom to water surface at throat
  3. Floor of flume to water surface at measuring point
  4. Floor of flume to water surface at throat
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78) How many gallons of water can a 200 cubic-foot tank hold?
  1. 1,017
  2. 1,496
  3. 1,938
  4. 2,432
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79) An industry has a wastewater discharge of 40,000 gallons per day containing 15 mg/L of cyanide. What is the industry’s mass emission rate of cyanide in pounds per day?
  1. 5 lb/day
  2. 8 lb/day
  3. 10 lb/day
  4. 12 lb/day
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80) A wastewater treatment plant exceeds its daily nitrogen discharge limit on 3 days in January, 1 day in March, 2 days in September, and 5 days in December. The penalty is $2,000 for every day the discharge limit was exceeded. Calculate the plant's total penalty for the year.
  1. $18,000
  2. $20,000
  3. $22,000
  4. $24,000
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81) How should an inspector respond when an unknown material that is neither flammable nor asphyxiating is found in a collection system?
  1. Assume the unknown material was an accidental spill
  2. Disregard the unknown material until next time
  3. Try to trace the unknown material back to the industrial source
  4. Wait for the unknown material to arrive at the treatment plant
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82) Which type of safety system involves a team leader calling their staff periodically (every hour, for example) to make sure they are safe?
  1. Check-call
  2. Checklist
  3. Contact-tracing
  4. Dispatch
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83) What is dangerous about gasoline in sewers?
  1. It can cause sewage to expand
  2. It can explode
  3. It can rust pipes
  4. It can thicken sewage and cause blockages
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84) In wastewater systems, what does the term "peaking factor" mean?
  1. A value indicating the smoothness of the interior of a pipe
  2. The maximum momentary load placed on a water treatment plant, pumping station, or distribution system
  3. The ratio of a maximum flow to the average flow
  4. The ratio of true power to apparent power in an electrical circuit
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85) What is the purpose of ultraviolet light in wastewater treatment?
  1. To improve water taste
  2. To kill pathogens
  3. To reduce water hardness
  4. To remove suspended particles
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86) If the residual chlorine is 2.0 mg/L and the chlorine dosage is 8.0 mg/L, what is the chlorine demand?
  1. 4.0 mg/L
  2. 6.0 mg/L
  3. 10.0 mg/L
  4. 16.0 mg/L
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87) For new developments, a district charges a sewer impact fee of $3,200 per REC (Residential Equivalent Connection), where one REC is 240 gallons per day. If a new build will have 20 employees and each employee will use 15 gallons of water per day, then what is the sewer impact fee?
  1. $1,000
  2. $2,000
  3. $3,000
  4. $4,000
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88) The CWA makes it unlawful to discharge any pollutant from a point source into navigable waters unless a(n) ___________ is obtained.
  1. amendment
  2. demineralization certificate
  3. discrete conveyance
  4. permit
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89) What is the maximum residual chlorine dioxide level allowed by the EPA for drinking water?
  1. 0.004 ppm
  2. 0.02 ppm
  3. 0.8 ppm
  4. 5 ppm
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90) Which of these is always required when working in a confined space?
  1. Breathing apparatus
  2. Continuous air monitoring
  3. Fall arrest tripod
  4. Radio
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91) Which of these gases is odorless?
  1. Arsine
  2. Bromine gas
  3. Carbon monoxide
  4. Hydrogen sulfide
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92) Which option is NOT available to an inspector if a request for entry to perform an inspection is denied?
  1. Exercise authority to enter the facility without permission
  2. Issue a citation for denial of access
  3. Leave and immediately collect samples for analysis
  4. Threaten the company with criminal prosecution
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93) Animal slurries are usually treated by:
  1. anaerobic lagoons
  2. brine treatment
  3. electrochemical coagulation
  4. reverse osmosis membrane filtration
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94) What is the normal sampling frequency for water companies carrying out operator self-monitoring (OSM)?
  1. 1 or 2 samples per year
  2. 4 or 8 samples per year
  3. 12 or 24 samples per year
  4. 16 or 28 samples per year
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95) What association is devoted to eliminating death and injury due to fire hazards?
  1. CWEA
  2. NFPA
  3. NSC
  4. OSHA
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96) Before entering an industrial facility for an inspection, why should an environmental compliance officer first visit the sampling points and collect wastewater samples?
  1. To collect an unbiased wastewater sample
  2. To ensure following proper chain of custody procedures
  3. To minimize the time required of the industrial contact
  4. To present the industrial contact with the results of the analysis of sample
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97) What are the sources of pollutants in stormwater runoff?
  1. Drag out dripping on the floor
  2. Products which have spilled on the grounds
  3. Rinse waters
  4. Scrubber wastewater
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98) Physicochemical wastewater treatment methods, such as coagulation and reverse osmosis, are examples of which level of treatment?
  1. Primary
  2. Quarternary
  3. Secondary
  4. Tertiary
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99) What is the purpose of the buffer area in traffic control?
  1. To redirect traffic out of its normal path
  2. To separate traffic from the work area
  3. To store tools and machinery
  4. To warn drivers of work or danger
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100) A containment tank has dimensions of 15×15×2 feet. Calculate the number of gallons of water the containment tank can hold, assuming there is also a cylindrical metal column In the middle of the tank with a diameter of 2 feet and a height of 10 feet.
  1. 3319 gallons
  2. 3349 gallons
  3. 3366 gallons
  4. 3389 gallons
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101) When collecting samples to be analyzed for volatile organic compounds, to which point should you fill the vial?
  1. Completely full
  2. Filled with about one inch of space at the top
  3. Four-fifths full
  4. Half full
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102) For how long is the BOD₅ test run?
  1. 5 minutes
  2. 5 hours
  3. 5 days
  4. 5 weeks
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103) What is "direct runoff"?
  1. A discharge from the end of a pipe, often containing pollutants
  2. A pipe that carries stormwater but not domestic and industrial wastewater
  3. Wastewater that flows out of a sanitary sewer as a result of an overflow
  4. Water that flows over the ground surface directly into streams, rivers, or lakes
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104) What is the minimum number of years a POTW must retain Industrial User records?
  1. 2 years
  2. 3 years
  3. 4 years
  4. 5 years
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105) Bubbler systems:
  1. break down foam on the water surface
  2. measure the depth of water
  3. measure the flow rate of streams
  4. mix water in stilling wells
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106) If a wastewater treatment plant can treat 150,000 gallons of sewage in 1 hour, then how many gallons of sewage should it be able to treat in 8 hours?
  1. 150,000
  2. 400,000
  3. 800,000
  4. 1,200,000
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107) Which of these is most likely to be a source of catastrophic discharges?
  1. Canneries
  2. Chemical plants
  3. Construction sites
  4. Dairies
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108) An industry has a discharge of 16,000 gpd. A composite sample of 1 liter is needed. The sampler takes 125 ml each time it is activated. For a flow proportional sample, at what gallon interval should the sampler activate to take a sample?
  1. 1,000 gallons
  2. 2,000 gallons
  3. 3,000 gallons
  4. 4,000 gallons
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109) The following magnesium results, in mg/L, were taken throughout the day: 0.38, 0.71, 0.47, 0.60, 0.12, 0.11, 0.10, 0.71 Calculate the mean of these results.
  1. 0.25
  2. 0.27
  3. 0.37
  4. 0.40
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110) In the rapid infiltration method of land treatment:
  1. collected water is discharged into the stream
  2. effluent is applied on the land by ridge-and-furrow spreading
  3. purification is achieved through biological, physical, and chemical means
  4. wastewater is stored in large ponds
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111) Domestic water generated by small communities can be treated by:
  1. barren land
  2. coastal lands
  3. constructed wetlands
  4. range land
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112) Which of these test papers is used to detect the presence of hydrogen sulfide?
  1. Flame retardant paper
  2. Lead acetate paper
  3. M-9 CAD paper
  4. Peracetic acid test strips
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113) COD tests are reported in what units?
  1. mL/mol
  2. mg/L
  3. mol/L
  4. mol/g
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114) Which containers are designed exclusively to separate non-polar liquids at oil refineries?
  1. API separator
  2. PE separator
  3. Plastic separator
  4. Polyethylene separator
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115) Which term means a conveyance, such as a pipe, ditch, or channel, from which pollutants are discharged?
  1. Effluent
  2. Emergent outflow
  3. Overflow
  4. Point source
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116) Which of these tests is reported in mg/L?
  1. Temperature
  2. Total toxic organics
  3. Turbidity
  4. pH
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117) What is the flashpoint of car gasoline?
  1. 32°C
  2. 52°C
  3. 82°C
  4. −43°C
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118) Facilities do not need to file a Spill Prevention, Control, and Countermeasure (SPCC) plan with the EPA if the oil storage capacity on the facility is less than how many gallons in total?
  1. 10,000
  2. 20,000
  3. 30.000
  4. 40.000
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119) What is the most used toxic pollutant in leather tanning?
  1. Chromium
  2. Copper
  3. Cyanide
  4. Phenol
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120) A rectangular containment tank has a length of 15 feet and a width of 10 feet. To the nearest foot, how tall does the tank need to be to hold 10,000 gallons of water?
  1. 6 feet
  2. 7 feet
  3. 8 feet
  4. 9 feet
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121) The Environment Protection Agency provides which web-based tool that calculates and reports facility pollutant discharges based on NPDES permit limit and DMR data?
  1. NPDES E-Reporting Tool
  2. Pollutant Head Tool
  3. Toxics Follow-up Tool
  4. Water Pollutant Loading Tool
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122) Why are septum vials used for samples to be tested for total toxic organics?
  1. To comply with hazardous waste regulations
  2. To prevent cross-contamination with grab samples
  3. To prevent sample contact with air
  4. To prevent skin contact with toxic organic compounds
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123) Most wastewater is treated through the separation of solids and liquids, typically by:
  1. crystallization
  2. distillation
  3. sedimentation
  4. stripping
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124) Flow-proportioned automatic samplers should be programmed to collect a sample at least once every ____ hour(s) over a 24-hour period.
  1. 1
  2. 3
  3. 8
  4. 12
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125) Which instrument measures water turbidity?
  1. Flowmeter
  2. Nephelometer
  3. Spectrometer
  4. Venturimeter
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126) Which of these is a source of dilute solutions that may be discharged to the pretreatment system or POTWs?
  1. Reject products
  2. Spent plating baths
  3. Static drag out solutions
  4. Stormwater runoff
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127) Which of these is found on Self-Monitoring Report (SMR) forms?
  1. Air quality index
  2. Child-resistant closures
  3. Hazard pictograms
  4. Laboratory test results
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128) What is the main goal of sample storage procedures?
  1. To accumulate a large enough sample for analysis
  2. To allow samples to accumulate before analysis
  3. To efficiently use the analyst's time
  4. To maintain the integrity of the sample until analysis
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129) In which temporary traffic control zone does the work take place?
  1. Activity area
  2. Advance warning area
  3. Termination area
  4. Transition area
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130) Chemical oxygen demand is reported in what unit?
  1. kg/meq
  2. meq/mole
  3. mg/L
  4. moles/mL
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131) A sulfuric acid solution contains 12% sulfuric acid and has a density of 1.4 g/mL. How many grams of sulfuric acid are in one liter of the solution?
  1. 117 g/L
  2. 168 g/L
  3. 857 g/L
  4. 1167 g/L
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132) A wastewater sample is to be analyzed for volatile organic compounds but the water contains chlorine. What can be used to preserve the sample?
  1. 1 mol of nitric acid
  2. 1:2 ratio of 50% ethanol
  3. 2 drops of a 25% ascorbic acid solution
  4. 5 mL of a 10% mercuric chloride solution
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133) In which stage of sewage treatment do microorganisms consume the organic components of the sewage?
  1. Primary
  2. Secondary
  3. Tertiary
  4. Quarternary
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134) Temporary traffic control zones generally have five sections: the advanced warning area, the transition area, the buffer area, the work area, and the ___________ area.
  1. controlled
  2. final warning
  3. late warning
  4. termination
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135) What does the C in COD stand for?
  1. Carbon
  2. Chemical
  3. Chlorine
  4. Combined
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136) In water pipes, what is a "springline"?
  1. A line that represents the elevation of energy head of water flowing in a pipe
  2. An outlet for overload conditions during peak flows
  3. The horizontal centerline of a pipe
  4. The lowest point of the channel inside a pipe
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137) For what purpose do metal plating industries use ion exchange?
  1. Byproduct recovery
  2. Volume reduction
  3. Wastewater equalization
  4. Wastewater segregation
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138) Which of these is a method commonly used to thicken activated sludge before treatment?
  1. Aeration
  2. Dissolved air flotation
  3. Sand filtering beds
  4. Vacuum filtration
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139) Wastewater from toilets is known as:
  1. blackwater
  2. brownwater
  3. graywater
  4. whitewater
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140) What is the "scouring velocity" of a river?
  1. The average velocity of the river during flooding
  2. The minimum velocity required for zero turbulence
  3. The velocity that prevents particles from settling on the river bottom
  4. The velocity which pulls plants out of the riverbed
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141) Lime reacts with carbon dioxide in wastewater to produce which chemical?
  1. Activated carbon
  2. Calcium carbonate
  3. Sodium carbonate
  4. Sodium hydroxide
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142) Fees imposed by a local government on a new development project that pay for all or a portion of the costs of providing public services to the new development are called:
  1. buy-in fees
  2. growth-related improvement fees
  3. impact fees
  4. reimbursement fees
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143) Bacteria used in water treatment plants function optimally at which temperature?
  1. 5–15°C
  2. 15–25°C
  3. 25–35°C
  4. 35–40°C
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144) What is a Bronsted-Lowry acid?
  1. A chemical compound with the structural formula HNCO
  2. A salt that produces an acidic solution after being dissolved in a solvent
  3. A substance that donates hydrogen ions during a chemical reaction
  4. An organic compound that reacts with alcohols to form uric arid
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145) Water samples to be analyzed for bacteria should be kept at what temperature?
  1. 21°C
  2. 37°C
  3. 4°C
  4. −6°C
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146) Water samples to be analyzed for cyanide should be kept at what temperature?
  1. −6°C
  2. 4°C
  3. 21°C
  4. 37°C
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147) What container and preservative are needed for samples to be analyzed for total or dissolved metals?
  1. Cubitainer, H₂SO₄ to pH < 2
  2. Glass, HCL to pH > 9
  3. Glass, zinc acetate + NaOH to pH > 9
  4. Plastic, HNO₃ to pH < 2
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148) What container and preservative are needed for samples to be analyzed for bromide?
  1. Plastic, no preservative
  2. Plastic, NaOH
  3. Glass, HNO₃
  4. Glass, zinc acetate + NaOH
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149) Which container and preservative are needed when collecting a sample to be analyzed for sulfides?
  1. Glass, HNO₃ to pH > 9
  2. Glass, H₂SO₄ to pH < 2
  3. Plastic, HCl to pH < 2
  4. Plastic, zinc acetate + NaOH to pH > 9
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150) What container and preservative are needed for samples to be analyzed for oil and grease?
  1. Glass, HCl to pH < 2
  2. Glass, zinc acetate + NaOH to pH > 9
  3. Plastic, HNO₃ to pH < 2
  4. Plastic, NaOH to pH > 9
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