090118 Ash pond 2.jpg

Earth-moving equipment chugs along at a coal ash pond east of Plant Hammond in October of 2016. Work at that particular pond has pretty much been completed. / file photo

The report also cites high levels of boron and sulfate in the groundwater supply in the area of Plant Bowen at Euharlee outside of Cartersville.

Arsenic is known to cause multiple types of cancer and neurological brain damage, boron causes developmental issues in humans, such as low birth weight and stunted growth, cobalt has negative impacts in the heart, blood and thyroid, molybdenum damages the kidneys and liver in high concentrations and sulfate can lead to diarrhea and be dangerous to young children.

Using data developed by Georgia Power from test wells at the plants, the report claims Ash Pond 1 at Plant Hammond has high concentrations of arsenic and molybdenum. The arsenic recorded at test well HGWC-13 in the southwest corner of Ash Pond 1 has recorded arsenic at 30 times the federal drinking water standard. Molybdenum from HGWC-8 on the eastern side of the same ash pond was more than 10 times the EPA health advisory for that substance.

The report alleges that Georgia Power’s closure plan for Ash Pond 3 at Plant Hammond involves dewatering the ash and placing a cover over the remaining material. The report reads, "This ash pond currently contains over 1.2 million cubic yards (tons) of ash buried 44 feet deep into the ground next to the Coosa River. If the ash is in contact with underlying groundwater, toxic contaminants will continue to leak indefinitely into the groundwater after the cap is installed. The polluted groundwater is likely to flow offsite into the nearby Coosa River just a few hundred feet from the pond."

Aaron Mitchell, general manager for environmental affairs at Georgia Power, said the utility is using teams of third party engineers to develop specific plans for each unique ash pond at 12 different sites all over the state.

"Ash Pond 3 is closed in place but not just simply closed in place. We're adding additional features as part of that closure in the form of advanced engineering methods to ensure that, at the end of the closure, that it will produce results that result in groundwater protection over the long haul," Mitchell said. "Then we're going to monitor that around the ash pond, provide that information to EPD, all under their oversight, for 30 years after its closed."

The report also points out that the closure plan for the largest ash disposal pond at Plant Bowen also involves dewatering and leaving more than 21 million cubic yards (tons) in place. The environmental groups cite a 2002 sinkhole issue at the site which resulted in the spill of more than two million pounds of ash, an estimated 260 pounds of arsenic, into a tributary of the Etowah River. They allege that simple closure of the ash pond is "unlikely to prevent future toxic concentration at the site."

"That closure plan, which was just filed with the Georgia EPD in the form of a permit application the week of Thanksgiving specifically addresses stability, the geology around Plant Bowen and presents engineering solutions to ensure that we can safely close that pond," Mitchell said.

"Ultimately we will wait on the outcome of EPDs permit issuance, taking into consideration our engineering plans and construction reports," Mitchell said.