West Virginia Wastewater Class II Operator Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

West Virginia Wastewater Class II Operator Practice Exam Questions And ( Answers) Plus Rationales 2026 Q&A Instant Download Pdf

• Which of the following is the primary purpose of a grit chamber in

wastewater treatment?

• Remove organic matter
• Remove dissolved solids
• Remove heavy inorganic particles
• Reduce bacteria

Rationale: Grit chambers are designed to remove sand, gravel, and

other heavy inorganic particles before they damage downstream equipment. 1 / 4

• In activated sludge systems, what is the primary function of aeration?
• Settle solids
• Provide oxygen for microbial activity
• Remove grit
• Disinfect effluent

Rationale: Aeration supplies oxygen to microorganisms, enabling

them to break down organic pollutants.

• The ideal pH range for most biological wastewater treatment

processes is:

A. 4.5–5.5

B. 5.5–6.5

C. 9.0–10.0

D. 6.5–8.5

Rationale: Most microorganisms thrive in a near-neutral pH

environment, typically between 6.5 and 8.5.

4. Sludge digestion primarily reduces:

• Nitrogen content
• Organic solids
• Heavy metals
• Phosphorus

Rationale: Digestion breaks down organic solids in sludge, reducing

volume and stabilizing it. 2 / 4

• Which process is most effective for removing ammonia from

wastewater?

• Chlorination
• Nitrification
• Sedimentation
• Coagulation

Rationale: Nitrification biologically converts ammonia to nitrite and

nitrate, removing it from wastewater.

6. The primary reason for using a bar screen is to:

• Remove bacteria
• Reduce BOD
• Remove large solids
• Settle grit

Rationale: Bar screens trap large objects such as sticks, rags, and

plastics to prevent equipment damage.

• What is the main function of primary sedimentation tanks?
• Reduce BOD biologically
• Remove settleable solids
• Remove dissolved nutrients
• Aerate wastewater

Rationale: Primary sedimentation tanks allow heavy solids to settle

out by gravity. 3 / 4

8. The term BOD stands for:

• Biological Oxidation Demand
• Biochemical Oxygen Demand
• Biological Organic Decomposition
• Basic Oxidation Design

Rationale: BOD measures the amount of oxygen microorganisms

consume while decomposing organic matter.

9. A sudden increase in toxic industrial wastewater can cause:

• Increased nitrification
• Improved settling
• Shock load leading to treatment failure
• Increased sludge digestion

Rationale: Shock loads of toxic substances can kill microorganisms

and disrupt biological treatment.

• Which of the following is considered a suspended solids removal

process?

• Chlorination
• Sedimentation
• Filtration
• Coagulation

Rationale: Sedimentation allows suspended solids to settle out of

wastewater.

• / 4