What type of release would result in a slow-flowing liquid dispersion?

A pool release refers to a situation where a liquid hazardous material accumulates in a low-lying area, forming a standing pool. This type of release typically occurs when the liquid is contained or does not flow away rapidly from the source of the spill. The slow-flowing nature of the dispersion is a result of the liquid's physical properties and the landscape where it has pooled, which can lead to a gradual dispersion over time rather than a more rapid evaporation or vaporization.

In contrast, a cone release involves the dispersion of a gaseous substance that rises and spreads in a conical shape from a point source. A plume release typically refers to the dispersal of gas in a column that moves away from the source, which is more dynamic and often associated with airflow. A steam release is characterized by the vaporization of liquid into gas, which would dissipate quickly rather than forming a slow-flowing body of liquids. Thus, a pool release is the only option that accurately describes the scenario of a slow-flowing liquid dispersion.