Airdate: Nov 14, 2017
Scientist: Madeline Schreiber
Coal Ash and Water
You don't want coal ash to end up in a water supply.
When you burn coal to make energy in a steam plant, you end up with coal ash. Where you don't want coal ash to end up in is in a water supply. I'm Jim Metzner and this is the Pulse of the Planet.
Schreiber: A coal ash pond is a shallow depression where they store the coal ash after they've retrieved it from the burners. They can vary in size. Modern ones do need to be lined so that the coal ash can't linteract with water and have that water pick up trace elements and go into the groundwater system. We don't want that to happen.
Madeline Schreiber is a professor of Geosciences at VA Tech.
Schreiber: Arsenic, potentially uranium, nickel, cobalt, chromium,other trace elements that may have been present in the coal originally if that gets associated with the ash and the ash gets into a water supply, then we get concerned that those trace elements may come off the coal ash into the water.
In 2014 the coal ash retention pond at the Dan River Steam Plant in North Carolina failed.
Schreiber: There was a storm water pipe that went underneath the retention pond that had broken. And that ash from the pond drained through the pipe and went straight into the river.
Early on, when state agencies were doing water sampling, there were a couple of occurrences of elevated arsenic concentrations, and that caused a lot of concern. Since then however, the arsenic concentrations have gone down. :40 Our sampling has not revealed elevated arsenic in the river itself
It turns out there are other places besides retention ponds that coal ash can end up in.
Schreiber: Many different researchers have worked on how you can incorporate coal ash into things like concrete and mix it into asphalt to use for road material. If we can find good ways to use that, where there's low risk of contamination, then that would be great because then, it would save landfills from having to deal with ash we could potentially use it beneficially.
I'm Jim Metzner and this is the Pulse of the Planet.