On Sunday afternoon, a helicopter flew behind the Horry County Government and Justice Center before hovering for a minute to pick up one-ton sandbags and fly them to dikes surrounding the old Grainger power plant’s coal ash ponds, one of which contains 200,000 tons of coal ash.
The helicopter dropped the sandbags on top of the dikes to provide additional protection from the flooding Waccamaw River, which the National Weather Service predicts will hit a record 22-foot crest on Tuesday.
On Sunday, the river was at just over 20 feet.
“The river has not crested, so we’re not quite halfway done,” Santee Cooper spokeswoman Mollie Gore said. “Everything is holding up the way it was intended.”
To prepare for the flood, Santee Cooper has reinforced the dikes with sandbags, brought in bags of rocks to fill any breaches in the dike, installed an aquadam and silt fence to contain the coal ash, and filled the ash ponds with water to equalize pressure on both sides.
So far, Gore said there’s no evidence that any of the coal ash in the sediment of the ponds has escaped into the river.
“And by filling the ponds with water ahead of the river over-topping, it reduces the chances that it is going to get stirred up,” Gore said.
Waccamaw Riverkeeper Cara Schildtknecht said the river breached one of the ponds that was already mostly cleaned out. But it’s getting close to flowing into the pond that still holds coal ash. The ash contains contaminates like arsenic and lead, which can be harmful to fish.
“Major concerns are just with the coal ash contaminating the river,” Schildtknecht said. “If that happens, there could be heavy metals in the river that could potentially impact wildlife. We don’t really have a concern at this point in terms of drinking water, so at least that’s a good side of things.”
She said Santee Cooper was doing everything possible to prevent a breach.
“They’re doing their sampling that they’re required to do by DHEC, trying to make sure they stay on top of things,” Schildtknecht said. “They’ve been very cooperative with us along the way, we really couldn’t ask for much more of them.”
Santee Cooper has been taking samples of the Waccamaw to test for contaminates and form a baseline for comparison to determine if any coal ash leaks.
“Sampling will let us know if there’s further action we need to take afterwards,” Gore said.
Schildtknecht said that because drinking water wasn't being threatened, she didn't believe there was cause for concern about a disease outbreak.
But she did warn against bacteria in the river.
"Even though we don’t expect there to be impacts to human health from coal ash ponds, there could be concerns to human health with bacteria," she said. "So we urge people to stay out of floodwaters if at all possible."