See aerial photos of the spill
Unedited aerial video of the spill:
Duke said on Monday night that 50,000 to 82,000 tons of ash has spilled from the unlined pond, or enough to fill 20 – 32 Olympic swimming pools. It’s unclear how much has spilled as of Tuesday night. 
The spill is the second in the past month in which hazardous chemicals related to burning coal have threatened local drinking water. Freedom Industries spilled a chemical used to “clean” coal into the Elk River in West Virginia on Jan. 8, tainting the drinking water for 300,000 people there.  The coal ash that Duke Energy spilled is a waste product from coal combustion.
The Dan River spill raises serious questions about whether people’s drinking water is safe, whether Duke Energy knew about the risk posed at this and other coal ash ponds, and whether company executives acted quickly enough in alerting the public after the spill. “Our rivers should not be at risk of turning grey or black from coal ash leaks, and our drinking water should not be at risk of turning toxic,” Greenpeace Charlotte Field Organizer Monica Embrey said. “Duke told us repeatedly its coal ash ponds are safe, but they were wrong.”
Greenpeace is calling on Duke to answer the following questions:
1. Is the drinking water for people living in the town of Dan River contaminated with metals? Danville city officials have said that their water, post-treatment, “met public health standards” but it’s unclear whether the city has tested for toxic heavy metals like selenium and mercury. 
2. Why did it take Duke Energy up to 24 hours to report the spill? Duke notified the public via press release at 4:03 pm on Monday, but said a security guard first noticed the low pond levels on Sunday afternoon. Given the potential for contamination of drinking water with heavy metals, why weren’t local residents told immediately?
3. What did Duke know about potential problems at the Dan River coal ash site? A September 2009 report by the EPA to Duke noted multiple problems with the dam, including: “Two stormwater pipes pass under the original pond and discharge into the Dan River. Notes on historic drawings indicate that these pipes were installed with three feet of cover minimum. Detailed engineering reports and drawings for the original embankment, including records of the original foundation treatment, were not provided as part of this review.”  Why did Duke not provide detailed engineering reports as part of that 2009 review? How could a broken stormwater pipe cause this spill if it was installed with three feet of cover? Did Duke know about potential risks posed by the stormwater pipes?
4. Duke says on its web site that “We are confident that each of our ash ponds has the structural integrity necessary to protect the public and the environment.” Does it still feel confident in that assessment of each of its ash ponds?  Duke Energy operates 23 coal ash ponds in North Carolina, including two that threaten Charlotte’s water supply at the now-retired Riverbend coal plant. “Once Duke Energy fully remediates the leak in Dan River, it should immediately move to clean up its remaining coal ash ponds, including those at the Riverbend coal plant which threaten Charlotte’s drinking water supply,” Embrey said.
NOTES:  http://www.charlotteobserver.com/2014/02/03/4661193/duke-energy-plant-reports-coal.html#.UvFecfldW7w
Contact: Monica Embrey, 773-419-0963,