Risk Analysis and Mitigation Flashcards
7 cards from real CES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Risk Analysis and Mitigation flashcards as text
A chemical has a Bioaccumulation Factor (BAF) of 50,000. What does this imply for ecological risk assessment?
Answer: The chemical accumulates in biota to levels 50,000 times higher than water concentrations, raising food-chain concerns
A high BAF indicates significant bioaccumulation from water into aquatic organisms, which can lead to biomagnification through food chains and increased risk to top predators.
Which of the following best characterizes the 'precautionary principle' in environmental risk management?
Answer: Protective action should be taken when there is credible evidence of harm, even without full scientific certainty
The precautionary principle holds that lack of complete scientific certainty is not a reason to delay protective measures when evidence suggests significant or irreversible harm.
What is the role of a Toxicity Reference Value (TRV) in ecological risk assessment?
Answer: It serves as a benchmark dose or concentration below which adverse effects on wildlife are not expected
A TRV is an ecotoxicological benchmark—analogous to an RfD for humans—used to calculate hazard quotients by comparing wildlife exposure estimates to the effect threshold.
In a risk assessment for a brownfield redevelopment, why would future land use matter when calculating risk-based cleanup levels?
Answer: Exposure assumptions (frequency, duration, body weight) vary significantly between residential and commercial/industrial scenarios
Cleanup levels are directly tied to exposure assumptions that differ by land use—residential scenarios assume more frequent and longer-duration contact, yielding more stringent cleanup targets than industrial scenarios.
What distinguishes 'risk assessment' from 'risk management' in the environmental context?
Answer: Risk assessment characterizes the nature and magnitude of risks; risk management involves decisions about how to respond to those risks
Risk assessment is the scientific process of evaluating hazards and exposure; risk management is the broader decision-making process that weighs those risks against technical, economic, social, and legal factors.
Which statistical distribution is most commonly used to model contaminant concentration data in environmental risk assessment when data are right-skewed?
Answer: Lognormal distribution
Environmental contaminant concentrations typically follow a lognormal distribution due to their natural variability and the presence of occasional high outliers, making lognormal statistics appropriate for risk calculations.
Under EPA guidance, what is the 'reasonable maximum exposure' (RME) scenario used for?
Answer: Estimating a high-end, plausible exposure that protects most but not all individuals in the population
The RME represents a high-end (approximately 90th–95th percentile) but plausible exposure scenario, used by EPA to ensure risk estimates are protective without being unrealistically conservative.