Tue February 4, 2014
Coal Ash Spills From Storage Pond At Duke Energy's Dan River Plant
Engineers with Duke Energy are working to fix a broken drain pipe under a coal ash storage pond in northern North Carolina. As much as 10 percent of the coal ash in the pond may have spilled into the Dan River, just south of the Virginia state line. WFAE's Ben Bradford updates Morning Edition Host Kevin Kniestedt on the situation.
KK: So, a stormwater pipe that runs underneath the Dan River coal plant burst. Ash and water from the pond began flowing through the pipe into the Dan River. Duke’s been trying to plug the leak since a security guard noticed it on Sunday. What’s the effect been?
BB: As of last night, Duke estimated 27 million gallons of water and as much as 8 percent of the ash in the pond has flown into the river. A spokesman says the flow has slowed down some, but there’s still 600 gallons of water a minute flowing into the river, along with an amount of ash they wouldn’t estimate.
KK: What’s that look like?
BB: There’s a lot of people up there taking pictures, including Matt Wasson from the environmental group Appalachian Voices. Here’s how he described the river at the site of the leak.
WASSON: It’s a little reddish brown upstream. Downstream, you can’t see an inch into the water. It’s just this almost milky, dark grey consistency. We pulled some of the sediment off the bottom of the river, and it’s just black, ashy stuff.
BB: It’s also scary for the environment and for people who get their drinking water from the Dan River. An EPA report from 2009 estimated a breach at the plant would cause significant damage to the environment. The ash contains all kinds of chemicals and heavy metals, including arsenic and selenium. So far, drinking water seems okay. The city of Danville gets its drinking water about twenty miles downstream, and say so far the water, which is filtered, is fine. State regulators say their initial tests came back okay—but those didn’t test for heavy metals.
KK: What’s happening to stop the flow?
BB: Duke’s working on that. Monday, engineers tried to use a temporary, inflatable plug, but that failed. It kept getting pushed out by the pressure of the water. Duke spokeswoman Erin Culbert says a crew dug out the pipe yesterday.
CULBERT: We have located the hole in the pipe today so that’s a great advancement. Secondly, they are also working to use a camera to video what’s happening inside the pipe, so we have an opportunity to design an engineering solution that will be most effective.
BB: Once that happens, Culbert says they’ll turn to studying and cleanup of the effects.
KK: Do we have a sense of what those will be?
BB: Not yet. Obviously the coal ash sediment in the river isn’t good. If you look back five years, Tennessee had the largest coal ash spill in U.S. history—a billion gallons. That’s obviously way, way bigger than the estimate we’re getting from this spill, but … it closed the river for months and five years on residents still say the wildlife hasn’t come back. The Tennessee Valley Authority, which owned that pond, faced multiple lawsuits, and has paid over a billion dollars to clean up. It also caused property damage to hundreds of homes. Again, that was much bigger than this current spill.
KK: These sites are monitored by the utility, as well as state and federal regulators. How does something like this happen?
BB: Yeah, that’s a good question. On one hand, there are over 300 coal plants across the country, some with multiple ash ponds. In many cases, you’re talking about structures built sixty or seventy years ago. You could say there have been relatively few problems. On the other hand, I think people would be surprised at how these sites are regulated. The EPA doesn’t count coal ash as a hazardous material, although it’s changing that in December. As for the ponds, all those ones from the 60s, 70s, and 80s are grandfathered in, so they don’t have to meet the state requirements of ones built today. Matt Wasson at Appalachian Voices blames lack of oversight for this current spill.
WASSON: I think that Duke is likely to try very hard to make this seem like a one-off, a freak accident that wouldn’t happen elsewhere. These aren’t one-offs, this is a fundamental problem in how the safety of these ponds are being regulated and enforced.
BB: For instance, almost all of North Carolina’s lie on earthen beds—there’s no lining to stop the water from seeping into the ground, like would be required today. That includes ponds at the Allen plant in Gaston County and the Riverbend plant at Mountain Island Lake.
KK: And separately from these spills, Duke’s already involved in lawsuits over how it stores coal ash.
BB: Right. The state was under pressure from environmental groups and launched lawsuits last year against Duke for the ponds at all 14 of its North Carolina plants. The gist of the suit is that the ponds are seeping unpermitted ash into the groundwater and rivers. State regulators and Duke agreed on a settlement, which requires a small fine and more testing about the damage, and they’re waiting for a judge to approve it.
KK: Okay, thanks, Ben.
BB: Thank you.
WFAE’s Duncan McFadyen tells All Things Considered Host Mark Rumsey about the spill.
MR: First of all, remind us where coal ash comes from and why it’s a concern.
DM: This is what’s left over after power plants burn coal. It’s stored in large ponds or lagoons at the plants, and it contains metals that are toxic at high concentrations---things like arsenic, cadmium, and chromium.
MR: How did Duke Energy realize something was wrong at the Dan River plant?
DM: Duke says that early Sunday afternoon, a security guard first noticed the pond level looked low. Now we call these “ponds,” but this one is 27 acres. they then discovered a 48 inch stormwater pipe running under the pond had broken, and water and coal ash were spilling through it into the Dan River. Duke says it relies on these guards for this kind of information. Here’s Duke Energy spokeswoman Lisa Hoffman:
HOFFMAN: “Well this is why we have folks that are patrolling the site, so that if anything unusual is happening, It’s detected as soon as possible.”
MR: So they’re depending on security guards to notice anything?
DM: That’s right. So this had to be significant to get noticed. Remember it’s 27 acres.
MR: Give us an idea of how much coal ash has spilled.
DM: The Dan River plant was retired back in 2012. So the pond was not filled to capacity, but as much as 10 percent of what was being stored there spilled into the river. Duke compares the volume of coal ash spilled to 20 to 32 olympic sized swimming pools. And in addition to 50,000 to 82,000
pounds tons of coal ash, as much as 27 million gallons of water escaped through the pipe.
MR: Is the leak under control now?
DM: There’s a temporary plug in the pipe, which Duke says has slowed the flow considerably, but engineers are still working on a more permanent solution.
MR: Is there a risk of something like this happening somewhere else?
DM: Duke says none of its other plants in the Carolinas have stormwater pipes running under coal ash ponds like at the Dan River site. There’s just one other plant, in Ohio, that uses this same design, and the company is monitoring it. Duke has 13 other coal plants in North Carolina; about half of them have been retired. The Allen plant near Belmont is still running and Riverbend plant on Mountain Island Lake, which is Charlotte’s major drinking water source, is retired.
MR: How has this coal ash spill affected the Dan river?
DM: We spoke to Matt Wasson today. He and two others from the advocacy group Appalachian Voices are taking water quality samples in the river near the plant. He says upstream, the water was a little cloudy and brown from recent rain and snow, but downstream, the water is a gray color, and so cloudy it’s hard to see more than an inch below the surface…
WASSON: “We actually used a bucket to pull the sediment out of the river, and it’s just this black ashy stuff…and this was about 2 miles from the spill site.”
We don’t have results from any of the water tests yet. But Wasson’s group, the state, and Duke Energy have all taken samples, some of them as far downstream as Danville Virginia, close to 20 miles away.
MR: Has Danville’s drinking water been affected?
DM: So far, the city says their water is fine, but they’re closely monitoring for any changes.
MR: OK Duncan, Thanks.
Science & Environment
Science & Environment
Science & Environment