KINGSTON, T.N. - Coal ash is made up of metals you know can be dangerous like Arsenic and Mercury. You would assume coal ash would have an environmental impact. To estimate the future impact with North Carolina's spill, 2 Wants To Know dug into the past. Five years ago a coal ash spill in Tennessee dumped 1,458,000 tons into the Emory river. It happened at the Kingston Fossil Plant-- right outside of Knoxville. Now this plant is not owned by Duke Energy. And five years later, the cleanup is almost finished.
An EPA study on the site claims the ash might not have much of an environmental impact. They'll get to see if their claim stands the test of time-- because the agency didn't clean-up a section of river. The coal ash is still there on purpose.
That testing looked at 20 different types of wildlife. Both on land and some living under water. All of the wildlife live in one section of the Emory river. It's the part the EPA didn't clean-up. You can't tell from just looking at the clear water, but 300,000 tons of coal ash is still there.
For the last five years researchers tested birds, turtles, fish. The results? No long-term problems.
"The data that I'm seeing from 2013 says this system has basically recovered to pre-spill conditions," Craig Zeller with the EPA said.
The only creature of concern: insects. Scientists estimate their population decreased by 25 percent.
"This ash when it gets down into the substrate can get kinda crusty. I wouldn't say as hard as concrete, but it gets a little crust to it. So it could be the fact that the bugs could not burrow into it," Zeller said.
To see if the crusty coal ash would impact the rest of the ecosystem, the EPA tested the animal which eats the insects: the tree swallow. Scientists built bird houses as central nesting areas to test eggs and baby birds. All the tests so far have come back clean - no problems.
So why spend money to clean up any coal ash spill? The EPA says it's still possible one day - in the future- there could be a problem.
"You could. We just don't know here," Zeller said.
Again, the EPA left about 300,000 tons of coal ash in the Tennessee river for testing purposes. The North Carolina spill was 39,000 tons. So the EPA says it's likely the ash in North Carolina will not have a major impact:
"I would expect the results to be very similar to what we found here," Zeller said.