Energy and Utilities Water and Wastewater Utilities 1 — Questions and Answers
Question 1: Which federal law sets standards for drinking water quality in the United States?
- Clean Water Act
- Safe Drinking Water Act (SDWA) (Correct answer)
- Resource Conservation and Recovery Act
- National Environmental Policy Act
Correct answer: Safe Drinking Water Act (SDWA)
The Safe Drinking Water Act (SDWA) of 1974 authorizes the EPA to set national standards for contaminants in public drinking water systems.
Question 2: What is the primary purpose of chlorination in drinking water treatment?
- Removing heavy metals
- Disinfecting water to kill pathogens (Correct answer)
- Softening hard water
- Removing turbidity
Correct answer: Disinfecting water to kill pathogens
Chlorination is the most widely used water disinfection method, killing bacteria, viruses, and protozoa that could cause waterborne illness.
Question 3: What does 'turbidity' measure in water quality assessment?
- Chemical oxygen demand
- Temperature variation in water
- Cloudiness or haziness caused by suspended particles (Correct answer)
- pH level of water
Correct answer: Cloudiness or haziness caused by suspended particles
Turbidity measures the clarity of water by quantifying light scattered by suspended particles; high turbidity can indicate contamination.
Question 4: What is a 'combined sewer overflow' (CSO)?
- A system that combines drinking water and wastewater pipes
- The discharge of untreated sewage and stormwater during heavy rain from combined sewer systems (Correct answer)
- An advanced wastewater treatment process
- A method to reuse treated wastewater
Correct answer: The discharge of untreated sewage and stormwater during heavy rain from combined sewer systems
CSOs occur in older combined sewer systems when storm runoff overwhelms capacity, causing untreated sewage mixed with stormwater to discharge to waterways.
Question 5: What treatment process removes dissolved minerals like calcium and magnesium from water?
- Chlorination
- Sedimentation
- Water softening (ion exchange) (Correct answer)
- UV disinfection
Correct answer: Water softening (ion exchange)
Water softening uses ion exchange resins to replace calcium and magnesium ions (which cause hardness) with sodium or potassium ions.
Question 6: What is the purpose of the Clean Water Act Section 404 program?
- Setting drinking water standards
- Regulating discharge of dredged or fill material into waters of the US, including wetlands (Correct answer)
- Requiring wastewater plants to meet effluent limits
- Monitoring groundwater quality
Correct answer: Regulating discharge of dredged or fill material into waters of the US, including wetlands
Section 404 of the Clean Water Act requires a permit from the Army Corps of Engineers before discharging fill material into navigable waters or wetlands.
Energy and Utilities Water and Wastewater Utilities 1
Which federal law sets standards for drinking water quality in the United States?