CWEA Environmental Compliance (2025) COMPREHENSIVE
QUESTIONS AND VERIFIED DETAILED SOLUTIONS
|COMPLETE SOLUTIONS |A+ GRADED |100% CORRECT!!
An industry operating an 8-hour shift, 5 days per week, generates 100,000 gallons of
wastewater per shift. Their pretreatment system has a capacity of 150 gallons per
minute. How long must the pretreatment facility operate to process the wastewater
generated each day? - ANSWER✔✔-11.1 hours
An industry has five sewer connections with the following discharge rates: 1) 300 gpd,
2) 75 gpd, 3) 725 gpd, 4) 1,200 gpd, 5) 200 gpd A flow-weighted composite sample of 5
liters is desired. How many milliliters of sample from each connection should be
composited? - ANSWER✔✔-600, 150, 1450, 2400, 400
Prohibited discharges from industrial users to POTWs, as stipulated in the Clean Water
Act, are pollutants that: - ANSWER✔✔-create a fire or explosion hazard in the sewer or
POTW.
"MSDS" is an acronym for what? - ANSWER✔✔-Material Safety Data Sheet
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,Safety hazards associated with hydrogen sulfide in sewer systems include: -
ANSWER✔✔-toxic gasses.
A significant industrial user can be defined as: - ANSWER✔✔-a federal categorical
industrial user.
Lead acetate paper is used to determine the presence of: - ANSWER✔✔-hydrogen
sulfide.
What is the average detention time, in minutes, for a 40,000 gpd flow going through a
1,500-gallon interceptor? - ANSWER✔✔-54 minutes
The following type of flow measuring device can be installed in a pipe flowing full: -
ANSWER✔✔-Venturi.
What total volume of spill containment capacity in gallons is needed for the following
tanks if a 12-inch rainfall occurs during a 24-hour period on a common 200-foot by 200-
foot spill-containment pad? Assume 100 percent containment of all tank capacity is
needed. Tank I: Cube, 6 ft wide, 6 ft long, and 6 ft high. Tank II: Rectangular, 4 ft wide,
20 ft long, and 3 ft high. Tank III: Cylindrical, 8 ft in diameter and 9 ft high. -
ANSWER✔✔-305,992 gallons
An industry has a wastewater discharge of 10,000 gallons per day containing 5 mg/L of
copper. What is the industry's mass emission rate of copper in pounds per day? -
ANSWER✔✔-0.42 lb/day
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,What kind of container and preservative is required for samples to be analyzed for oil
and grease? - ANSWER✔✔-Glass, Cool 4°C, H2SO4 to pH<2
A chain-of-custody form: - ANSWER✔✔-is the ability to trace sample possession and
handling from collection through analysis.
The BOD determination is an empirical test in which standardized laboratory
procedures are used to: - ANSWER✔✔-determine the relative oxygen requirements of
wastewaters, effluents, and polluted waters.
A confined space is one that: - ANSWER✔✔-is large enough to enter and work in, has a
restricted entry/exit, and is not meant for continuous occupancy.
Industrial plants producing wastes with a high suspended solids content include: -
ANSWER✔✔-breweries.
Whenever an inspector or sampling technician is in a manhole, how many people
should there be above to respond in the event of an emergency? - ANSWER✔✔-Two
Alkalinity is reported as: - ANSWER✔✔-alkalinity, mg/L CaCO3.
What is the normality of sodium hydroxide (NaOH) solution of 25 mL if a 0.01 N
sulfuric acid solution neutralizes 100 mL of the NaOH solution? - ANSWER✔✔-0.0025
N
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, A major pollutant of concern from a printed circuit board shop is: - ANSWER✔✔-
copper.
To find the proper protective gear to use while inspecting an area where a hazardous
chemical is used, you would: - ANSWER✔✔-check the MSDS for chemicals used.
Why are gasoline and volatile solvents objectionable when present in a sewer? -
ANSWER✔✔-They can produce an explosion hazard.
When inspecting a plating shop, personal protective equipment would include: -
ANSWER✔✔-eye goggles or face shield, chemical resistant gloves, and overalls.
A solution with a pH of 5 has a concentration of hydrogen ions that is how many times
higher than a solution with a pH of 7? - ANSWER✔✔-100 times higher
High pH wastewater is neutralized by adding: - ANSWER✔✔-H2SO4.
When working in the street, signs and cones are needed when: - ANSWER✔✔-over half
of the street is blocked.
What is the danger of asphyxiation set point for oxygen on an atmospheric monitor? -
ANSWER✔✔-19.5 percent
A common technology to recover chemicals from rinse water include: - ANSWER✔✔-
ion exchange.
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QUESTIONS AND VERIFIED DETAILED SOLUTIONS
|COMPLETE SOLUTIONS |A+ GRADED |100% CORRECT!!
An industry operating an 8-hour shift, 5 days per week, generates 100,000 gallons of
wastewater per shift. Their pretreatment system has a capacity of 150 gallons per
minute. How long must the pretreatment facility operate to process the wastewater
generated each day? - ANSWER✔✔-11.1 hours
An industry has five sewer connections with the following discharge rates: 1) 300 gpd,
2) 75 gpd, 3) 725 gpd, 4) 1,200 gpd, 5) 200 gpd A flow-weighted composite sample of 5
liters is desired. How many milliliters of sample from each connection should be
composited? - ANSWER✔✔-600, 150, 1450, 2400, 400
Prohibited discharges from industrial users to POTWs, as stipulated in the Clean Water
Act, are pollutants that: - ANSWER✔✔-create a fire or explosion hazard in the sewer or
POTW.
"MSDS" is an acronym for what? - ANSWER✔✔-Material Safety Data Sheet
OLIVIA GREENWAYS© 2025, ALL RIGHTS RESRVED 1
,Safety hazards associated with hydrogen sulfide in sewer systems include: -
ANSWER✔✔-toxic gasses.
A significant industrial user can be defined as: - ANSWER✔✔-a federal categorical
industrial user.
Lead acetate paper is used to determine the presence of: - ANSWER✔✔-hydrogen
sulfide.
What is the average detention time, in minutes, for a 40,000 gpd flow going through a
1,500-gallon interceptor? - ANSWER✔✔-54 minutes
The following type of flow measuring device can be installed in a pipe flowing full: -
ANSWER✔✔-Venturi.
What total volume of spill containment capacity in gallons is needed for the following
tanks if a 12-inch rainfall occurs during a 24-hour period on a common 200-foot by 200-
foot spill-containment pad? Assume 100 percent containment of all tank capacity is
needed. Tank I: Cube, 6 ft wide, 6 ft long, and 6 ft high. Tank II: Rectangular, 4 ft wide,
20 ft long, and 3 ft high. Tank III: Cylindrical, 8 ft in diameter and 9 ft high. -
ANSWER✔✔-305,992 gallons
An industry has a wastewater discharge of 10,000 gallons per day containing 5 mg/L of
copper. What is the industry's mass emission rate of copper in pounds per day? -
ANSWER✔✔-0.42 lb/day
OLIVIA GREENWAYS© 2025, ALL RIGHTS RESRVED 2
,What kind of container and preservative is required for samples to be analyzed for oil
and grease? - ANSWER✔✔-Glass, Cool 4°C, H2SO4 to pH<2
A chain-of-custody form: - ANSWER✔✔-is the ability to trace sample possession and
handling from collection through analysis.
The BOD determination is an empirical test in which standardized laboratory
procedures are used to: - ANSWER✔✔-determine the relative oxygen requirements of
wastewaters, effluents, and polluted waters.
A confined space is one that: - ANSWER✔✔-is large enough to enter and work in, has a
restricted entry/exit, and is not meant for continuous occupancy.
Industrial plants producing wastes with a high suspended solids content include: -
ANSWER✔✔-breweries.
Whenever an inspector or sampling technician is in a manhole, how many people
should there be above to respond in the event of an emergency? - ANSWER✔✔-Two
Alkalinity is reported as: - ANSWER✔✔-alkalinity, mg/L CaCO3.
What is the normality of sodium hydroxide (NaOH) solution of 25 mL if a 0.01 N
sulfuric acid solution neutralizes 100 mL of the NaOH solution? - ANSWER✔✔-0.0025
N
OLIVIA GREENWAYS© 2025, ALL RIGHTS RESRVED 3
, A major pollutant of concern from a printed circuit board shop is: - ANSWER✔✔-
copper.
To find the proper protective gear to use while inspecting an area where a hazardous
chemical is used, you would: - ANSWER✔✔-check the MSDS for chemicals used.
Why are gasoline and volatile solvents objectionable when present in a sewer? -
ANSWER✔✔-They can produce an explosion hazard.
When inspecting a plating shop, personal protective equipment would include: -
ANSWER✔✔-eye goggles or face shield, chemical resistant gloves, and overalls.
A solution with a pH of 5 has a concentration of hydrogen ions that is how many times
higher than a solution with a pH of 7? - ANSWER✔✔-100 times higher
High pH wastewater is neutralized by adding: - ANSWER✔✔-H2SO4.
When working in the street, signs and cones are needed when: - ANSWER✔✔-over half
of the street is blocked.
What is the danger of asphyxiation set point for oxygen on an atmospheric monitor? -
ANSWER✔✔-19.5 percent
A common technology to recover chemicals from rinse water include: - ANSWER✔✔-
ion exchange.
OLIVIA GREENWAYS© 2025, ALL RIGHTS RESRVED 4
