AEP AEP Air Quality & Atmospheric Science 1 — Questions and Answers
Question 1: The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) for how many 'criteria pollutants'?
- 4
- 6 (Correct answer)
- 8
- 10
Correct answer: 6
The EPA sets NAAQS for six criteria pollutants: particulate matter (PM2.5 and PM10), ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, and lead.
Question 2: Which NAAQS pollutant is primarily formed through photochemical reactions between NOx and volatile organic compounds (VOCs) in sunlight?
- Carbon monoxide
- Ground-level ozone (Correct answer)
- Sulfur dioxide
- Particulate matter PM2.5
Correct answer: Ground-level ozone
Ground-level ozone (tropospheric ozone) forms when NOx and VOCs react in the presence of sunlight, making it a secondary pollutant rather than a directly emitted one.
Question 3: Under the Clean Air Act, what designation is given to areas that do not meet NAAQS for a specific pollutant?
- Sensitive area
- Non-attainment area (Correct answer)
- Impairment zone
- Critical receptor area
Correct answer: Non-attainment area
Areas that fail to meet NAAQS are designated as non-attainment areas and must develop State Implementation Plans (SIPs) to achieve compliance.
Question 4: Which emission control program under the Clean Air Act uses a 'cap-and-trade' approach for sulfur dioxide?
- Title V Operating Permits
- New Source Review
- Acid Rain Program (Correct answer)
- National Emission Standards for Hazardous Air Pollutants
Correct answer: Acid Rain Program
The Acid Rain Program (Title IV of the CAA) established a cap-and-trade system for SO2 and NOx emissions from power plants to address acid deposition.
Question 5: What does the acronym 'PSD' stand for in Clean Air Act permitting?
- Pollutant Source Documentation
- Prevention of Significant Deterioration (Correct answer)
- Primary Source Designation
- Permitted Stationary Discharge
Correct answer: Prevention of Significant Deterioration
Prevention of Significant Deterioration (PSD) is a Clean Air Act permitting program that applies to new major sources or major modifications in attainment areas.
Question 6: Which type of air dispersion model is most commonly used by EPA for point source impact assessments?
- SCREEN3
- AERMOD (Correct answer)
- CALPUFF
- ISC3
Correct answer: AERMOD
AERMOD (American Meteorological Society/EPA Regulatory Model) is EPA's preferred steady-state Gaussian dispersion model for near-field point source applications.
AEP AEP Air Quality & Atmospheric Science 1
The Clean Air Act requires EPA to set National Ambient Air Quality Standards (NAAQS) for how many 'criteria pollutants'?