Environmental Compliance Inspector Soil and Land Contamination 2 — Questions and Answers
Question 1: When evaluating soil contamination from a lead smelter, which exposure pathway is typically the primary concern for residential land use?
- Dermal contact with contaminated surface water
- Ingestion of contaminated soil by children (Correct answer)
- Inhalation of contaminated groundwater vapors
- Consumption of fish from nearby streams
Correct answer: Ingestion of contaminated soil by children
For lead-contaminated soil at residential sites, incidental soil ingestion by children is the critical exposure pathway because children have hand-to-mouth behavior and greater bioavailability of lead.
Question 2: Under CERCLA, what is a Potentially Responsible Party (PRP)?
- A federal agency that oversees Superfund site cleanup
- Any party that may be liable for cleanup costs including current owners, past owners, generators, or transporters (Correct answer)
- Only the current property owner at the time of EPA listing
- A state environmental agency authorized to conduct remediation
Correct answer: Any party that may be liable for cleanup costs including current owners, past owners, generators, or transporters
CERCLA imposes strict, joint and several liability on four classes of PRPs: current owners/operators, past owners/operators, generators who arranged for disposal, and transporters who selected the disposal site.
Question 3: What is the significance of vapor intrusion in soil contamination investigations?
- It refers to stormwater runoff carrying contaminants into nearby waterways
- It describes the migration of volatile contaminants from subsurface soil or groundwater into overlying buildings (Correct answer)
- It is the process by which bacteria break down hydrocarbons in contaminated soil
- It describes the upward movement of contaminated groundwater to the surface
Correct answer: It describes the migration of volatile contaminants from subsurface soil or groundwater into overlying buildings
Vapor intrusion occurs when volatile organic compounds (VOCs) in contaminated soil or groundwater migrate as vapors through the subsurface into buildings, creating indoor air quality concerns.
Question 4: A compliance inspector discovers discolored soil and a petroleum odor near an old UST. What is the first action to document?
- Collect soil samples and send to a certified lab immediately
- Photograph and GPS-coordinate the observation, recording depth, color, odor, and extent in the field log (Correct answer)
- Notify the property owner and request immediate excavation
- Issue a notice of violation and set a 30-day compliance schedule
Correct answer: Photograph and GPS-coordinate the observation, recording depth, color, odor, and extent in the field log
Thorough field documentation — photos, GPS coordinates, descriptive observations of color, odor, and apparent extent — must be completed before any other action to create an accurate compliance record.
Question 5: Which cleanup standard applies when contaminated soil will remain on-site under a cap rather than being removed?
- Background-based cleanup levels assuming pristine conditions
- Risk-based cleanup levels combined with institutional and engineering controls (Correct answer)
- Drinking water maximum contaminant levels (MCLs) applied directly to soil
- Universal treatment standards from RCRA LDR regulations
Correct answer: Risk-based cleanup levels combined with institutional and engineering controls
When soil is capped in place, risk-based cleanup levels are used alongside engineering controls (the cap) and institutional controls (deed restrictions) to prevent exposure.
Question 6: The Toxicity Characteristic Leaching Procedure (TCLP) is used to determine whether contaminated soil is classified as what?
- A solid waste requiring Subtitle D disposal
- A characteristic hazardous waste under RCRA (Correct answer)
- A Superfund-listed hazardous substance
- A regulated pollutant under the Clean Water Act
Correct answer: A characteristic hazardous waste under RCRA
TCLP simulates leaching in a landfill environment; if the leachate exceeds regulatory thresholds for listed metals or organics, the soil exhibits the toxicity characteristic and is classified as RCRA hazardous waste.
Environmental Compliance Inspector Soil and Land Contamination 2
When evaluating soil contamination from a lead smelter, which exposure pathway is typically the primary concern for residential land use?