Georgia Power is gearing up to drain the remaining coal ash pond at Plant Yates.
Once the pond is fully “dewatered,” there will be no more wet storage of ash on the plant property, eliminating the risk of a catastrophic discharge of coal ash into the Chattahoochee River from a dam failure.
The dewatering process of Ash Pond 2 is set to begin in mid-May, according to Aaron Mitchell, general manager of environmental affairs for Georgia Power.
Draining the water out of the large pond is a major step in completing the ash pond closure on the Plant Yates property, located along the Chattahoochee River in northwest Coweta.
The water will be pumped into a water treatment plant that has been built adjacent to the pond. Once treated, it will be discharged into the river.
Once the pond is drained, the coal ash – known in regulations as coal combustion residuals, or “CCRs,” will be removed from the pond and placed in an unlined Ash Management Area on another part of the Plant Yates property.
The water treatment plant is configured to treat 2,000 gallons per minute, and can go as high as 4,000 gpm, Mitchell said. There is continuous monitoring of the discharge, and discharge water is tested weekly. Mitchell said testing of river water upstream and downstream from the treatment plant must be done every two weeks, under the approved dewatering plan.
The sampling date is submitted to the Georgia Environmental Protection Division each month. Georgia Power has hired a consultant “to summarize the data so that it is easier to understand and is not just the lab report,” said Mitchell. That information will be posted on Georgia Power’s website.
The water is tested for contaminants associated with coal ash, as well as those associated with stormwater runoff, such as phosphorus and orthophosphate.
Contaminants being monitored include selenium, arsenic, mercury, chromium, lead, cadmium, zinc and nickel.
Groundwater and river regulated separately
Groundwater testing is also done in various wells on the property. There are several contaminants that are tested for in groundwater but not in the treated ash pond water, including barium, beryllium, antimony, cobalt, lithium, molybdenum, thallium and radium.
Stream discharges and groundwater pollution are governed by different laws, so each is tested for different pollutants.
The discharges into the river are regulated by the Clean Water Act, according to Kevin Chambers, spokesman for Georgia EPD. Groundwater standards come from the Safe Drinking Water Act. Additionally, the ash disposal on site is being regulated under the Georgia Comprehensive Solid Waste Management Act. Georgia’s Coal Combustion Residuals rule is authorized by the solid waste management act, he said.
Current discharges from ash ponds are regulated by a National Pollutant Discharge Elimination System permit. “The permit requires all water discharged from the ponds to meet permit limits, and we are in full compliance with the permit,” said Holly Crawford of Georgia Power.
“At Plant Yates, requirements in the Clean Water Act regulate discharges to surface waters through the NPDES program and ensure the discharges don’t cause or contribute to in stream water quality standard violations,” Chambers said.
While NPDES discharge permits go through a public comment process, the dewatering plan did not, said Chris Manganiello, water policy director for Chattahoochee Riverkeeper.
“When they did these dewatering plans, they did it outside of that public review process,” Manganiello said. “We consider the dewatering to be significant enough that it should trigger a permit review.”
There are also concerns that the dewatering plan isn’t legally enforceable in the same way the permit is.
The existing water discharge permit “doesn’t really consider a lot of the things they’re going to be monitoring in the dewatering plan,” Manganiello said. “When the permit itself has those effluent limits, they are enforceable. The way that the dewatering plan is added, it is not clear that they are legally enforceable."
Manganiello said Georgia Power’s response to those concerns is, "Well, the EPD is reviewing it. If they thought there was a problem, they would tell us."
Despite concerns about enforceability and ash storage in unlined landfills, "from our perspective, we’re happy that Georgia Power wants to dewater that pond and move the ash from that pond away from the river,” Manganiello said. Ash Pond 2 is only separated from the Chattahoochee by the pond dam itself.
“We would hate to have a huge dam blowout and have coal ash rush down the Chattahoochee River,” he said. “Moving it away from the river is a good thing.”
Dry – but not too dry
A dike has been built to divide the pond in half, and each half will be dewatered in turn.
Rainwater still flows into the pond, including all stormwater that flows over the other ash pond areas. Coal ash is being removed from several former ash ponds – which no longer hold water – and consolidated into two landfills on site. Stormwater that flows over other parts of the Plant Yates property has been diverted into other ponds that don’t contain coal ash, according to Mitchell.
The section of the pond closest to the Chattahoochee will be dewatered first. Once the ash is dry enough to excavate, it will be piled into rows for further drying. Then it will be trucked to the on-site landfills.
The ash needs to be dry, but not too dry, or dust starts to fly around. Dust suppression is required under the federal and state regulations, and nearby property owners who are seeing dust on their property can file complaints, said Manganiello.
When inhaled, coal ash dust is a fine-particulate pollutant. Breathing fine particles has been linked to heart disease, cancer, respiratory disease and stroke and can trigger inflammation and immune response, according to the Earth Justice report, “Ash in Lungs.”
Coal ash dust is also dangerous because of its components, including arsenic, mercury, lead and chromium, according to the report. Some of the coal ash components that have been found in groundwater, including beryllium and cobalt, are more dangerous when inhaled, according to the EPA.
Once the final pond is dewatered, all the ash will be dug out, as well as at least six inches of soil underneath the ash – to ensure that all the ash is out.
The groundwater monitoring wells on the Plant Yates property range from 29 to 128 feet in depth, though the “down gradient wells” below the ash landfills range from 29 to 55 feet.
Once both halves of Ash Pond 2 are dewatered and excavated, the half furthest from the river will become a “service pond” for the plant. It will collect rainwater and cooling water, and water from it will be used to create the steam that generates electricity at Plant Yates, according to Mitchell.
Plant Yates no longer burns coal. Georgia Power retired Plant Yates units one through five in 2015 following approval by the Georgia Public Service Commission through the 2013 Integrated Resource Plan. Units six and seven remain in operation and are fueled by natural gas.
Regulated by state and federal rules
Both federal and state regulations – also known as “rules,” as opposed to laws – regulate the storage and disposal of CCRs. Regulations are created by government agencies – in this case the EPA and the Georgia Department of Natural Resources – and are authorized by federal and state laws. The EPD is a department of the DNR.
According to the EPA’s “The Basics of the Regulatory Process,” laws often don’t include all the details needed to explain how to follow a law, and regulations are authorized in order to make laws work on a day-to-day level. Regulations set specific requirements about what is legal and what is not.
On the federal level, the authorizing law is the Resource Conservation and Recovery Act, which took effect in 1976. The CCR regulations took effect in 2015, and were written after the 2008 failure of an ash pond dike in Tennessee that led to 1.1 billion gallons of ash slurry flooding into the Clinch River. The rule was amended with additional requirements in 2018.
The Water Infrastructure Improvements for the Nation Act was passed in 2016, and allows for states to create CCR programs, as long as the state regulations are at least as protective as the federal ones.
The state rule was created in response to changes at the federal level, said Chambers. It was approved by the Georgia DNR Board. The state rule goes farther than federal rules and regulates some ash ponds and landfills that weren't regulated under the federal rules.
Under state regulations, the deadline to submit permit applications for ash pond closures was November 2018.
Plant Yates has been operational since the 1950s, and during that time, CCRs have been stored both wet in ponds and dry in landfills.
Georgia Power submitted applications for its ash pond closure process at multiple plants in November, and those applications are still being reviewed. There are multiple former ponds on the Plant Yates site. Some are being excavated, with all the ash being put into a landfill built on top of two former ash ponds, Pond B-prime and Pond 3.
Those ponds been drained and will be closed in place in the Ash Management Area, an on-site landfill. The ash from Ash Pond 2, as well as the other former ash ponds, will be added to the AMA landfill. Another landfill, known as R6, is also on site.
None of the ponds or landfills on the Plant Yates site have liners.
Mitchell said the ash pond and landfill closure process is expected to be fully complete by 2023.
Georgia Power ‘confident’
When asked why the two permanent landfills on site won’t have liners separating the coal ash from the ground, Mitchell said the federal and state rules allow for the "closure in place” without liners.
The ash closure permits at Plant Yates haven’t yet been approved. “I’m confident that our plans are in compliance with the federal and state rules,” Mitchell said.
As the applications are reviewed, “I do anticipate the EPD to ask us to do some things differently, and we’ll certainly respond to what they ask us to do and what those permits require,” Mitchell said.
All the ponds closest to the river are being closed by excavation and removal. Mitchell said the ash is being consolidated so that it will have a smaller footprint, and the impermeable cover that will go over the ash landfills will extend further than a landfill cover would traditionally go.
Mitchell said that making the cover larger will increase its effectiveness and prevent rainwater from coming in contact with the ash, which could wash ash away from the landfill site and introduce it into the groundwater. Currently, rainwater runoff from the ash goes into Ash Pond 2.
Manganiello said Chattahoochee Riverkeeper is glad that the ash is being stored on Plant Yates property and not being trucked elsewhere, but is concerned that the landfills aren’t lined.
“If the world was a perfect place, we would see coal ash stored in a dry state, in a lined landfill, away from water,” Manganiello said.
“They could have stored this in a lined landfill, which would have been beneficial in the long run.”
To learn more about the Plant Yates ash pond closure process, visit https://www.georgiapower.com/c... .