CEA Water Quality & Waste Management 4 — Questions and Answers
Question 1: Which wastewater treatment process removes nitrogen through sequential anoxic and aerobic zones where bacteria convert ammonia to nitrogen gas?
- Chemical coagulation-flocculation
- Biological nitrification-denitrification (Correct answer)
- Membrane bioreactor filtration
- Activated carbon adsorption
Correct answer: Biological nitrification-denitrification
Biological nitrification-denitrification uses nitrifying bacteria (aerobic) and denitrifying bacteria (anoxic) to convert ammonia to nitrate and then to nitrogen gas.
Question 2: A CEA auditor finds that a company's waste oil storage tanks lack secondary containment. Which regulation is most likely violated?
- 40 CFR Part 261 hazardous waste identification
- 40 CFR Part 265 interim status standards for TSDFs
- 40 CFR Part 279 used oil management standards (Correct answer)
- 40 CFR Part 302 CERCLA hazardous substance release reporting
Correct answer: 40 CFR Part 279 used oil management standards
40 CFR Part 279 establishes used oil management standards including secondary containment requirements for used oil storage tanks.
Question 3: Under the Clean Water Act, what is the distinction between a 'point source' and a 'nonpoint source' discharge?
- Point sources discharge to groundwater; nonpoint sources discharge to surface water
- Point sources are confined discrete conveyances; nonpoint sources are diffuse runoff (Correct answer)
- Point sources require state permits; nonpoint sources require federal permits
- Point sources are regulated under RCRA; nonpoint sources under CERCLA
Correct answer: Point sources are confined discrete conveyances; nonpoint sources are diffuse runoff
Point sources are identifiable, confined conveyances (pipes, ditches) subject to NPDES permits, while nonpoint sources are diffuse pollutant inputs such as agricultural runoff not regulated by NPDES.
Question 4: Which characteristic makes a solid waste 'ignitable' under RCRA hazardous waste regulations (40 CFR Part 261.21)?
- Flash point below 60°C (140°F) for liquids (Correct answer)
- pH less than 2 or greater than 12.5
- Corrosion rate greater than 6.35 mm per year on steel
- Lethal dose (LD50) less than 50 mg/kg in oral rat studies
Correct answer: Flash point below 60°C (140°F) for liquids
A liquid waste is ignitable (hazardous characteristic D001) if it has a flash point below 60°C (140°F) as determined by standardized test methods.
Question 5: An auditor discovers a facility has an unpermitted discharge of process wastewater to a storm drain connected to a local creek. Which enforcement action is EPA most likely to pursue initially?
- Criminal prosecution for willful violation
- Administrative compliance order under CWA Section 309 (Correct answer)
- Natural resource damage assessment under CERCLA
- Emergency planning notification under EPCRA
Correct answer: Administrative compliance order under CWA Section 309
EPA typically begins with an administrative compliance order under CWA Section 309(a) requiring the facility to cease the unauthorized discharge and come into compliance.
Question 6: What is the purpose of a Toxicity Characteristic Leaching Procedure (TCLP) test in waste classification?
- To measure total heavy metal content in solid waste
- To simulate leaching of contaminants from waste in a landfill environment (Correct answer)
- To determine the ignitability of waste under combustion conditions
- To assess the biological treatment potential of organic waste
Correct answer: To simulate leaching of contaminants from waste in a landfill environment
TCLP simulates the leaching that occurs when waste is co-disposed in a municipal solid waste landfill, identifying wastes toxic enough to contaminate groundwater.
Question 7: Which document must accompany a hazardous waste shipment from a generator to a TSDF under RCRA?
- Spill Prevention Control and Countermeasure (SPCC) Plan
- Uniform Hazardous Waste Manifest (Correct answer)
- Emergency Response Guidebook (ERG)
- Land Disposal Restriction (LDR) notification only
Correct answer: Uniform Hazardous Waste Manifest
The Uniform Hazardous Waste Manifest must accompany all hazardous waste shipments, tracking the waste from generator to transporter to receiving TSDF.
CEA Water Quality & Waste Management 4
Which wastewater treatment process removes nitrogen through sequential anoxic and aerobic zones where bacteria convert ammonia to nitrogen gas?