A number of the Tennessee Valley Authority’s (TVA) risky coal ash waste impoundments were built using coal ash as a construction material, much like the failed pond at TVA’s Kingston plant. Today, just days before the 3-year anniversary of the devastating coal ash spill in Kingston, TN, the Southern Alliance for Clean Energy (SACE), Tennessee Clean Water Network (TCWN), Earthjustice and Environmental Integrity Project (EIP) together submitted a letter to the Tennessee Department of Environment and Conservation (TDEC) in which they highlighted the findings of a new report by an expert hydrogeologist. That report closely scrutinized the history and construction of “Ash Island,” the impoundment that holds toxic coal ash waste from TVA’s Johnsonville coal plant. The report also found that Johnsonville’s Ash Island was partially constructed using coal ash.
Following the December 2008 Kingston disaster, engineering reports demonstrated that degraded ash inside the Kingston dikes contributed to the catastrophic failure there. When initially used in dike construction, coal ash has properties similar to earthen material. However, when exposed to water over long periods of time the cohesion of ash will degrade, leading to weakened structural integrity of the coal ash pond and possible failure. This is the scenario that occurred at TVA’s Kingston plant.
“The dangerous conditions behind the Kingston disaster were not isolated. TVA has constructed other waste ponds using coal ash as a building material. Knowing this, TVA must move quickly to close these coal ash ponds and TDEC needs to make sure the closure is done safely,” said Josh Galperin with the Southern Alliance for Clean Energy. “On the third anniversary of the Kingston disaster we call on TVA and TDEC to ensure the disaster isn't repeated.”
On October 31, a bluff in Oak Creek, Wisc.—which supported a coal ash pond for We Energies’ Oak Creek Power Plant—collapsed into Lake Michigan. Upon further investigation regulators from Wisconsin’s Department of Natural Resources explained that the bluff itself was constructed using coal ash and that water leaking into the bluff over the past half century likely caused the failure.
TVA is in the early stages of closing all of its wet coal ash ponds as it transitions to dry ash management. SACE, TCWN, Earthjustice and EIP have been investigating TVA’s plan for the Johnsonville Ash Island and in the process of that investigation, discovered that the pond, like Kingston, was constructed with ash. The impoundment at TVA’s Colbert plant in northwest Alabama also uses ash as a construction material. Given that at least three ponds have used this dangerous method it is likely that the problem is more widespread.
“TVA has a long history of building dikes with coal ash, and as we now know from the Kingston disaster, ash is not durable building material,” said Abigail Dillen, Coal Program Director at Earthjustice. “TVA needs to move quickly to safely close down Ash Island and many other ash dumps that are ticking time bombs.”
In addition to the discovery that TVA used ash in dike construction, the groups’ investigation further concluded that TVA’s Johnsonville pond closure plan does not fully address this construction problem in order to prevent future disasters.
While the groups have submitted a letter to TDEC requesting that TDEC address these risks, there is no formal process for public input into the TVA pond closure plans, meaning there is no guarantee that TDEC or TVA will consider and respond to public concerns. Allowing TVA and TDEC to privately negotiate plans for dozens of wet ash ponds will not sufficiently safeguard the public interest in safe closure.
“It is too bad there is no public process established to vet the pond closure plans in light of the Kingston disaster,” said Renée Victoria Hoyos, executive director of the Tennessee Clean Water Network. “We hope that TDEC will do the right thing and open these plans for public scrutiny. As our letter points out, TDEC must address these ponds as both a water and solid waste issue to ensure that surface and groundwater are protected from pollution that will more than likely come from these ponds once they are closed.”