CEA Water Quality & Waste Management 3 — Questions and Answers
Question 1: What is the primary purpose of a groundwater monitoring program at a solid waste landfill under RCRA Subtitle D?
- To measure landfill gas generation rates
- To detect leachate migration and protect drinking water sources (Correct answer)
- To assess cover integrity and erosion
- To monitor stormwater runoff quality
Correct answer: To detect leachate migration and protect drinking water sources
Groundwater monitoring at landfills detects leachate releases that could contaminate underlying aquifers used as drinking water sources.
Question 2: Which technology is considered Best Available Technology Economically Achievable (BAT) for removing heavy metals from industrial wastewater?
- Activated sludge biological treatment
- Chemical precipitation followed by clarification (Correct answer)
- Reverse osmosis only
- Sand filtration
Correct answer: Chemical precipitation followed by clarification
Chemical precipitation (raising pH to form insoluble metal hydroxides) followed by clarification/filtration is the established BAT for heavy metal removal from industrial wastewater.
Question 3: Under the Safe Drinking Water Act, which contaminant category is regulated by Maximum Contaminant Level Goals (MCLGs) set at zero?
- Disinfection byproducts
- Nitrates and nitrites
- Known or probable human carcinogens (Correct answer)
- Secondary contaminants affecting taste
Correct answer: Known or probable human carcinogens
MCLGs are set at zero for known or probable human carcinogens because no safe exposure threshold is assumed for carcinogens under SDWA.
Question 4: A facility manages used oil that is mixed with listed hazardous waste solvents. How should this mixture be classified?
- Non-hazardous used oil subject to 40 CFR Part 279
- Hazardous waste subject to full RCRA Subtitle C requirements (Correct answer)
- Universal waste eligible for streamlined management
- Special waste requiring state-specific permits only
Correct answer: Hazardous waste subject to full RCRA Subtitle C requirements
When used oil is mixed with listed hazardous waste, the mixture is classified as hazardous waste and must be managed under full RCRA Subtitle C requirements.
Question 5: Which CWA provision specifically prohibits the discharge of dredged or fill material into waters of the United States without a permit?
- Section 301
- Section 311
- Section 404 (Correct answer)
- Section 402
Correct answer: Section 404
CWA Section 404, administered by the Army Corps of Engineers, regulates the discharge of dredged or fill material into waters of the United States, including wetlands.
Question 6: An auditor reviews a facility's stormwater pollution prevention plan (SWPPP). Which industrial activity would require coverage under the NPDES Multi-Sector General Permit?
- Office building with no outdoor industrial activity
- Manufacturing plant with outdoor material storage (Correct answer)
- Agricultural operation with less than 300 animal units
- Residential construction site under 1 acre
Correct answer: Manufacturing plant with outdoor material storage
Manufacturing facilities with outdoor industrial activities, including material storage, must obtain NPDES stormwater permit coverage under the Multi-Sector General Permit.
Question 7: What is the regulatory significance of the 'derived-from rule' under RCRA hazardous waste regulations?
- Waste generated from treating listed hazardous waste remains listed hazardous waste (Correct answer)
- Waste derived from recycling becomes non-hazardous
- Residues from permitted incinerators are always exempt
- Any waste mixed with non-hazardous materials is delisted
Correct answer: Waste generated from treating listed hazardous waste remains listed hazardous waste
The derived-from rule states that residuals generated from treating, storing, or disposing of listed hazardous waste retain the listed hazardous waste designation.
CEA Water Quality & Waste Management 3
What is the primary purpose of a groundwater monitoring program at a solid waste landfill under RCRA Subtitle D?