The Kingston Fossil Plant Spill was an environmental and industrial disaster that occurred on December 22, 2008, when a dike ruptured at a coal ash pond at the Tennessee Valley Authority's Kingston Fossil Plant in Roane County, Tennessee, releasing 1.1 billion US gallons (4.2 million cubic metres) of coal fly ash slurry.

The coal-fired power plant, located across the Clinch River from the city of Kingston, used a series of ponds to store and dewater the fly ash, a byproduct of coal combustion.

The spill released a slurry of fly ash and water which traveled across the Emory River and its Swan Pond embayment onto the opposite shore, covering up to 300 acres (1.2 km2) of the surrounding land.

[6] In November 2018, a federal jury ruled that the contractor did not properly inform the workers about the dangers of exposure to coal ash and had failed to provide them with necessary personal protective equipment.

[10] Fly ash is the fine particulate matter produced by the combustion of coal, which is collected rather than allowing it to escape into the atmosphere.

[13] At the time of the spill, the dredge cells contained a watery slurry of fly ash generated by the burning of finely ground coal at the power plant.

[10] Leaks at the Kingston ash ponds had reportedly been taking place since the early 1980s, and local residents said that the spill was not a unique occurrence.

[12] The two worst leaks occurred in 2003 and 2006 in which TVA suspended all ash deposits in the ponds to allow the dredge cells to dry out and stabilize.

[17] The spill began sometime between midnight and 1 a.m. Eastern Standard Time on December 22, 2008, when the dike surrounding the ash containment dewatering pond broke.

A report released in June 2009 identified the main cause of the spill as the result of slippage of an unstable layer of fine wet coal ash underneath the pond.

[41] The United States Senate Committee on Environment and Public Works, which oversees the TVA, held a hearing on January 8 to examine the disaster.

[21] On January 1 the first independent test results, conducted at the Environmental Toxicology and Chemistry laboratories at Appalachian State University, showed significantly elevated levels of toxic metals, including arsenic, copper, barium, cadmium, chromium, lead, mercury, nickel, and thallium in samples of slurry and river water.

[17] By early on December 24 a flyover by The New York Times did note repair work being done on the nearby railroad, which had been obstructed when 78,000 cubic yards (60,000 m3) of sludge-covered tracks.

[45] By December 30 the TVA had announced it was requesting the assistance of the Army Corps of Engineers to dredge the ash-filled Emory River to restore navigation.

[46] On January 1 the TVA announced that rather than attempting to clear away all of the slurry, they would be spraying seed, straw, and mulch on top of much of it to prevent dust scattering and erosion.

[29][47] In response to independent attempts at sampling of the water quality and the taking of photos, the TVA illegally detained, for approximately one hour, two members of the Knoxville-based environmental organization United Mountain Defense who were traversing public land in the area of the spill and warned three other individuals that any attempt to enter the public waterway would lead to prosecution.

[48] On December 26 TDEC stated that it was satisfied with the water quality in the wake of the spill but that it would continue to examine and deal with the potential for chronic health effects.

"[17] Chandra Taylor, an attorney with the Southern Environmental Law Center, called this statement irresponsible and stated that coal fly ash contains concentrated amounts of mercury, arsenic, and benzene.

"[29] Nevertheless, due to pressure exerted in 2000 by utilities, the coal industry, and Clinton administration officials, fly ash is not strictly regulated as a hazardous waste by the EPA.

[50] Thomas J. FitzGerald, the director of the environmental group Kentucky Resources Council and an expert on coal waste, reported that the ash should have been buried in lined landfills to prevent toxins leaching into the soil and groundwater, as recommended in a 2006 EPA report, and stated that he found it hard to believe that the state of Tennessee would have approved the ash disposal sites at the plant as a permanent disposal site.

[17] Bredesen acknowledged that TDEC, which regulates coal disposal, may have relied too much on TVA's own inspections and engineering studies about the ash ponds and dredge cells, and promised that there would be an extensive investigation into the cause of the spill in order to prevent similar disasters.

[51] At her Senate confirmation hearing on January 14, 2009, Lisa P. Jackson, then president-elect Barack Obama's choice to head the EPA under his administration, stated her intention to immediately review coal ash disposal sites across the country.

[54] That year, TVA committed to switching all of the ash storage facilities at their coal fired plants over to dry byproduct methods, which would reduce the chances of another spill.

The agency continued to classify coal ash as non-hazardous, thereby avoiding strict permitting requirements under Subtitle C of the Resource Conservation and Recovery Act (RCRA), but with new restrictions: Some of the provisions in the 2015 CCR regulation were challenged in litigation, and the United States Court of Appeals for the District of Columbia Circuit remanded certain portions of the regulation to EPA for further rulemaking.

[59] The EPA published a final RCR regulation on August 28, 2020, requiring all unlined ash ponds to retrofit with liners or close by April 11, 2021.

[60][61] EPA published its "CCR Part B" rule on November 12, 2020, which allows certain facilities to use an alternative liner, based on a demonstration that human health and the environment will not be affected.

[65] However, the workers were not provided with personal protective equipment necessary to prevent exposure to hazardous chemicals contained within the coal ash.

During this phase, the ash was safely transported to a permanent, lined, and leachate collecting facility in Perry County, Alabama, called Arrowhead landfill.

[64] This ruling was reversed by the U.S. Court of Appeals for the Sixth Circuit in 2015 after evidence was discovered that Jacobs Engineering had misled the workers about the dangers of coal ash.

[2] On May 18, 2022, the Sixth Circuit Court of Appeals rejected a claim by Jacobs Engineering that the company was immune from lawsuits since it was contracted by a federal agency.