Coal Dust Contamination: Environmental Concerns and Impact on Waterways

[Argentum Vulpes]

First I'm hoping this is in the right section.

There is a big debate in the high plains of the Rockies and the Pacific Northwest about coal being transported by rail in open top hopper cars. The debate seems to center on coal dust and bits of coal making its way into the water ways. As far as I can find the reason that the environmental groups says that this is a bad thing is that the coal will then cause elevated levels of heavy metals in the water ways, and these metals will enter into the food chain.

My question I was hoping that could be cleared up is what is the process that causes a bound heavy metal in a stable matrix to be leached or made mobile in some form that it can enter the food chain. I'm drawing a complete blank.

The cynical part of my brain just believes that this is an end run around to get coal plants to shut down. Hit the fuel, kill the plant. However that is a part of this thread that doesn't really need to be discussed here, maybe over in current events.

 

[256bits]

The basic questions to ask would be how much coal is lost from the open car transportation, what percentage of heavy metals is in coal, and if leached out is that amount significant compared to what is already in the environment.

 

[Argentum Vulpes]

The basic questions to ask would be how much coal is lost from the open car transportation, what percentage of heavy metals is in coal, and if leached out is that amount significant compared to what is already in the environment.

Good point, however I'd still like to know the process that leaches the metals out of a stable matrix. I know that combustion or strong acids can do that, but environmental process that can do this would be nice to know about.

 

[Bystander]

... a stable matrix...

Pause, and think --- a mixture of carbon compounds, finely divided (dust), plus exposure to oxygen, UV, and who knows how many microorganisms that have evolved to metabolize just about any substance containing reduced carbon. Bottom line --- coal is not "stable" --- not highly reactive at ambient conditions, but it will oxidize slowly, and if well insulated, can start wars ("Remember the Maine!").

 

[Argentum Vulpes]

Pause, and think --- a mixture of carbon compounds, finely divided (dust), plus exposure to oxygen, UV, and who knows how many microorganisms that have evolved to metabolize just about any substance containing reduced carbon. Bottom line --- coal is not "stable" --- not highly reactive at ambient conditions, but it will oxidize slowly, and if well insulated, can start wars ("Remember the Maine!").

Ok didn't think about that, and yes now that you mention it I do "Remember the Maine!" from history class. I guess I didn't state too clearly by what I meant by stable, I was thinking more about the oxides of the heavy metals. Granted chemistry was one of my weaker subjects, I was under the understanding that the heavy metals in coal were all oxides. The energy needed to liberate those oxides are greater then the energies that can be found in river beds, or lying on the ground.