When dealing with vapor dispersion, the ________ may need to be contained.

• A. Runoff
• B. Vapor Plume
• C. Concentration
• D. Airflow

Answer: (A)

Controlling secondary spread of hazardous material is crucial when vapor dispersion occurs. After a spill, some liquid can flow over surfaces as runoff. If that runoff isn’t contained, it can reach storm drains, soil, and waterways, spreading contamination and creating additional exposure risks. Containing runoff with barriers like dikes or berms, absorbent materials, and proper drainage controls helps keep the liquid from moving away from the incident scene and minimizes environmental impact. The other ideas describe what happens in the air or at different concentration levels, which are managed by ventilation, monitoring, or dilution, rather than something you physically cap and prevent from moving.