Pennsylvania Wastewater Operator Class E Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf
- What is the primary purpose of a wastewater treatment plant?
- Generate electricity
- Produce drinking water
- Remove pollutants from wastewater before discharge
- Increase water temperature
Rationale: The main goal of a wastewater treatment plant is to
remove pollutants and protect public health and the environment.
- Which of the following is considered a physical method of wastewater
- Chlorination 1 / 4
treatment?
- Biological digestion
- Sedimentation
- Filtration with chemicals
Rationale: Sedimentation is a physical process where solids settle out
of wastewater due to gravity.
- Which type of bacteria is primarily responsible for breaking down
- Sulfur bacteria
- Acidophilic bacteria
- Heterotrophic bacteria
- Nitrifying bacteria
organic matter in wastewater?
Rationale: Heterotrophic bacteria consume organic carbon and are
essential in the decomposition of organic matter.
- What does BOD stand for in wastewater treatment?
- Biological Oxidation Demand
- Biochemical Oxygen Demand
- Bacterial Oxidation Density
- Base Oxygen Diffusion
Rationale: BOD measures the amount of oxygen required by
microorganisms to decompose organic matter in water.
- Which unit process primarily removes suspended solids from
- Chlorination 2 / 4
wastewater?
- Aeration
- Sedimentation
- Filtration
Rationale: Sedimentation allows solids to settle out of the water,
reducing suspended solids.
6. pH is a measure of:
- Temperature
- Turbidity
- Acidity or alkalinity
- Total dissolved solids
Rationale: pH measures the hydrogen ion concentration and
indicates whether water is acidic, neutral, or basic.
- What is the typical pH range for wastewater entering a treatment
plant?
A. 1–3
B. 11–14
C. 6–9
D. 4–5
Rationale: Most domestic wastewater has a pH near neutral,
typically between 6 and 9.
- What is the primary function of a grit chamber?
- Remove oils
- Reduce BOD 3 / 4
- Remove sand, gravel, and heavy particles
- Kill bacteria
Rationale: Grit chambers allow heavy inorganic materials to settle
out, preventing damage to equipment.
- Which of the following is considered a chemical method of
- Filtration
- Sedimentation
- Coagulation and flocculation
- Screening
wastewater treatment?
Rationale: Coagulation and flocculation use chemicals to aggregate
fine particles for easier removal.
- Which type of filter media is commonly used in wastewater
- Sand
- Activated carbon
- Anthracite
- All of the above
filtration?
Rationale: Sand, activated carbon, and anthracite are all used
depending on the type of filtration process.
- What is the purpose of an aeration tank in activated sludge
- Remove grit
- / 4
processes?