CPWM Waste Characterization and Classification 4 — Questions and Answers
Question 1: What is the definition of 'mixed waste' in the context of U.S. waste classification?
- Waste that contains both organic and inorganic contaminants
- Waste that is both RCRA hazardous and radioactive under the Atomic Energy Act (Correct answer)
- MSW co-mingled with industrial solid waste
- Waste generated by two or more regulated facilities
Correct answer: Waste that is both RCRA hazardous and radioactive under the Atomic Energy Act
Mixed waste contains both RCRA-regulated hazardous constituents and radioactive material regulated under the Atomic Energy Act, falling under dual jurisdiction of EPA and NRC.
Question 2: Under the Land Disposal Restrictions (LDR) program, what must generators determine before disposing of hazardous waste?
- Generator category and monthly quantity only
- Whether the waste meets treatment standards before land disposal (Correct answer)
- Whether the waste qualifies for the household exclusion
- The total organic carbon content of the waste
Correct answer: Whether the waste meets treatment standards before land disposal
LDR (40 CFR Part 268) requires that hazardous wastes meet technology-based or concentration-based treatment standards before they can be placed in land disposal units.
Question 3: Which parameter is used in the RCRA reactivity characteristic to identify potentially explosive sulfide-bearing wastes?
- Flash point below 60°C
- pH above 12.5
- Generation of toxic gases when exposed to water or acid (Correct answer)
- TCLP extraction result exceeding regulatory limits
Correct answer: Generation of toxic gases when exposed to water or acid
Under 40 CFR 261.23, reactivity includes wastes that react violently with water or generate toxic gases (including hydrogen sulfide from sulfides) when mixed with water or acids.
Question 4: What does 'delisting' a waste mean under RCRA?
- Reclassifying a waste from Subtitle C to Subtitle D management
- Formally petitioning EPA to remove a specific waste from a hazardous waste listing (Correct answer)
- Downgrading a large quantity generator to small quantity status
- Exempting a waste from manifest requirements
Correct answer: Formally petitioning EPA to remove a specific waste from a hazardous waste listing
Delisting (40 CFR 260.20-260.22) allows a facility to petition EPA to exclude a specific waste from being listed hazardous based on facility-specific sampling and analysis showing it does not pose a hazard.
Question 5: Which waste category encompasses materials that are not solid wastes under RCRA because they are beneficially reused directly as raw materials?
- Characteristic hazardous wastes
- Reclaimed materials used as raw material substitutes without prior use as waste (Correct answer)
- F-listed solvents sent for energy recovery
- Universal wastes managed under 40 CFR Part 273
Correct answer: Reclaimed materials used as raw material substitutes without prior use as waste
Materials that are reclaimed and directly reused as legitimate raw material substitutes without first being discarded are not considered solid wastes under the RCRA recycling exclusions (40 CFR 261.2).
Question 6: In waste characterization for a Superfund (CERCLA) site, which analytical protocol is most commonly specified for comprehensive organic and inorganic characterization?
- Standard Methods for Examination of Water and Wastewater
- EPA Contract Laboratory Program (CLP) protocols (Correct answer)
- ASTM D4792 for potential of waste to generate heat
- NIOSH Manual of Analytical Methods
Correct answer: EPA Contract Laboratory Program (CLP) protocols
EPA's Contract Laboratory Program (CLP) protocols provide standardized, legally defensible analytical methods with rigorous QA/QC required for Superfund site characterization.
Question 7: A drum of waste is labeled 'D001.' What does this designation indicate?
- The waste contains listed benzene solvents
- The waste exhibits the ignitability characteristic (Correct answer)
- The waste is an acutely hazardous P-listed chemical
- The waste originates from petroleum refining
Correct answer: The waste exhibits the ignitability characteristic
D001 is the EPA hazardous waste code for the ignitability characteristic under 40 CFR 261.21, assigned to ignitable solid and liquid wastes.
CPWM Waste Characterization and Classification 4
What is the definition of 'mixed waste' in the context of U.S. waste classification?