FLORIDA ENVIRONMENTAL OPERATOR EXAM
LEVEL II PRACTICE QUESTIONS WITH CORRECT
ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2026 Q&A | INSTANT
DOWNLOAD PDF
1. Which of the following is the primary purpose of a water treatment
plant’s sedimentation process?
A. Disinfect water
B. Remove suspended solids
C. Adjust pH
D. Remove dissolved gases
Sedimentation allows particles to settle out of water by gravity,
reducing turbidity before filtration.
2. The term “BOD” stands for:
A. Biochemical Oxidation Demand
B. Biochemical Oxygen Demand
C. Biological Organic Decomposition
D. Basic Oxidation Design
BOD measures the amount of dissolved oxygen used by microorganisms
to decompose organic matter in water.
3. Chlorine is added to water primarily for:
A. Softening
B. Taste improvement
C. Disinfection
,D. pH adjustment
Chlorine kills bacteria, viruses, and other pathogens in water.
4. The safe residual chlorine level in drinking water is generally:
A. 0.05–0.1 mg/L
B. 0.1–0.3 mg/L
C. 0.2–0.5 mg/L
D. 1.0–2.0 mg/L
This ensures effective disinfection without producing harmful taste or
odor.
5. What is the main function of an aerator in wastewater treatment?
A. Remove solids
B. Provide oxygen to microorganisms
C. Settle sludge
D. Neutralize pH
Oxygen is required for aerobic biological treatment processes.
6. Which of the following parameters is used to monitor organic
pollution in water?
A. pH
B. BOD
C. Hardness
D. Chlorine residual
BOD reflects the amount of biodegradable organic material present.
7. Nitrification is a biological process that converts:
A. Ammonia to nitrogen gas
B. Ammonia to nitrites and nitrates
C. Nitrites to ammonia
, D. Organic matter to BOD
Nitrifying bacteria oxidize ammonia to nitrite, then to nitrate.
8. Sludge thickening is done to:
A. Remove pathogens
B. Increase water clarity
C. Reduce sludge volume
D. Disinfect water
Thickening concentrates solids to make further treatment or disposal
more efficient.
9. The presence of coliform bacteria in water indicates:
A. High mineral content
B. Alkalinity
C. Possible fecal contamination
D. Low oxygen
Coliforms are indicators of microbial contamination and sanitary
quality.
10. The process of removing dissolved minerals using an electric field
is called:
A. Filtration
B. Electrodialysis
C. Coagulation
D. Sedimentation
Electrodialysis uses an electric potential to separate ions from water.
11. The main purpose of coagulants in water treatment is to:
A. Adjust pH
B. Bind fine particles together
C. Disinfect water
LEVEL II PRACTICE QUESTIONS WITH CORRECT
ANSWERS (VERIFIED ANSWERS) PLUS
RATIONALES 2026 Q&A | INSTANT
DOWNLOAD PDF
1. Which of the following is the primary purpose of a water treatment
plant’s sedimentation process?
A. Disinfect water
B. Remove suspended solids
C. Adjust pH
D. Remove dissolved gases
Sedimentation allows particles to settle out of water by gravity,
reducing turbidity before filtration.
2. The term “BOD” stands for:
A. Biochemical Oxidation Demand
B. Biochemical Oxygen Demand
C. Biological Organic Decomposition
D. Basic Oxidation Design
BOD measures the amount of dissolved oxygen used by microorganisms
to decompose organic matter in water.
3. Chlorine is added to water primarily for:
A. Softening
B. Taste improvement
C. Disinfection
,D. pH adjustment
Chlorine kills bacteria, viruses, and other pathogens in water.
4. The safe residual chlorine level in drinking water is generally:
A. 0.05–0.1 mg/L
B. 0.1–0.3 mg/L
C. 0.2–0.5 mg/L
D. 1.0–2.0 mg/L
This ensures effective disinfection without producing harmful taste or
odor.
5. What is the main function of an aerator in wastewater treatment?
A. Remove solids
B. Provide oxygen to microorganisms
C. Settle sludge
D. Neutralize pH
Oxygen is required for aerobic biological treatment processes.
6. Which of the following parameters is used to monitor organic
pollution in water?
A. pH
B. BOD
C. Hardness
D. Chlorine residual
BOD reflects the amount of biodegradable organic material present.
7. Nitrification is a biological process that converts:
A. Ammonia to nitrogen gas
B. Ammonia to nitrites and nitrates
C. Nitrites to ammonia
, D. Organic matter to BOD
Nitrifying bacteria oxidize ammonia to nitrite, then to nitrate.
8. Sludge thickening is done to:
A. Remove pathogens
B. Increase water clarity
C. Reduce sludge volume
D. Disinfect water
Thickening concentrates solids to make further treatment or disposal
more efficient.
9. The presence of coliform bacteria in water indicates:
A. High mineral content
B. Alkalinity
C. Possible fecal contamination
D. Low oxygen
Coliforms are indicators of microbial contamination and sanitary
quality.
10. The process of removing dissolved minerals using an electric field
is called:
A. Filtration
B. Electrodialysis
C. Coagulation
D. Sedimentation
Electrodialysis uses an electric potential to separate ions from water.
11. The main purpose of coagulants in water treatment is to:
A. Adjust pH
B. Bind fine particles together
C. Disinfect water
