5.2 Pollution 环境污染
M: Well, no one could survive without water, but you see pollution has been making more and more water unable for drinking.
W: Yeah. Water pollution has for a long time been a major concern among the environmental issues.
M: But what are the sources of water pollution?
W: They could generally be divided into two categories: direct and indirect contaminant sources.
M: Well, direct ones are the pollution directly from factories, refineries waste treatment plants etc., aren’t they?
W: Yeah. They are emitted directly into urban water supplies.
M: But what about the indirect ones?
W: Indirect sources include contaminants that enter the water supply from soils or groundwater systems and from the atmosphere via rainwater.
M: I see. For the sake of us all, we should be an active participator in the prevention of it.
W: Sure. It's an issue asking for everyone's participation.
