AWWA Risk Assessment and Mitigation 3 — Questions and Answers
Question 1: Which chemical contamination scenario poses the GREATEST challenge for a water utility's risk mitigation plan due to detection difficulty?
- Turbidity spike from a storm event
- Odorless, colorless toxin introduced post-treatment (Correct answer)
- Algae bloom in a surface reservoir
- Iron and manganese from a groundwater source
Correct answer: Odorless, colorless toxin introduced post-treatment
Odorless, colorless toxins introduced post-treatment are difficult to detect by standard online sensors, maximizing exposure risk before discovery.
Question 2: A utility's Emergency Response Plan (ERP) should be updated whenever a significant change occurs. Which change MOST warrants an immediate ERP revision?
- A minor software patch to billing software
- Addition of a new water source or treatment process (Correct answer)
- Repainting the facility exterior
- Hiring a new administrative assistant
Correct answer: Addition of a new water source or treatment process
Adding a new water source or treatment process fundamentally changes the system's risk profile and requires ERP revision to address new hazard scenarios.
Question 3: What does 'residual risk' mean in the context of water system risk management?
- Risk eliminated by applying all possible countermeasures
- Risk remaining after mitigation measures have been implemented (Correct answer)
- Risk transferred entirely to insurance providers
- Risk associated only with legacy infrastructure
Correct answer: Risk remaining after mitigation measures have been implemented
Residual risk is the level of risk that remains after all selected countermeasures have been applied.
Question 4: Which approach best describes a 'defense-in-depth' strategy for a water treatment plant?
- Relying on a single high-quality perimeter fence
- Applying multiple overlapping layers of security controls (Correct answer)
- Outsourcing all security functions to a third party
- Installing one comprehensive alarm system
Correct answer: Applying multiple overlapping layers of security controls
Defense-in-depth uses multiple overlapping layers so that failure of any single control does not result in a successful breach.
Question 5: For a water utility performing a risk assessment, 'asset characterization' involves:
- Documenting all physical, cyber, and chemical assets and their criticality (Correct answer)
- Calculating the annual maintenance budget
- Training staff on emergency procedures
- Filing reports with the state drinking water program
Correct answer: Documenting all physical, cyber, and chemical assets and their criticality
Asset characterization identifies and describes system components including their function, value, and criticality to system operations.
Question 6: A cross-connection between the potable water system and a non-potable source represents which type of hazard?
- Natural hazard
- Physical security hazard
- Water quality contamination hazard (Correct answer)
- Cyber threat
Correct answer: Water quality contamination hazard
Cross-connections allow non-potable water or contaminants to enter the distribution system, posing a water quality contamination risk.
Question 7: In risk prioritization, which scenario would typically receive the HIGHEST risk ranking?
- Low likelihood, low consequence event
- High likelihood, low consequence event
- Low likelihood, high consequence event with no countermeasures (Correct answer)
- Moderate likelihood, moderate consequence event with strong countermeasures
Correct answer: Low likelihood, high consequence event with no countermeasures
A high-consequence event with no existing countermeasures receives the highest risk ranking even if likelihood is low, because the potential impact is catastrophic.
AWWA Risk Assessment and Mitigation 3
Which chemical contamination scenario poses the GREATEST challenge for a water utility's risk mitigation plan due to detection difficulty?