* 5.4 million cubic yards (or 1.2 billion gallons): spilled ash
* $1.2 billion: Estimated final cleanup cost, resulting in an additional 69 cents per month on each ratepayer's bill until 2024.
* 181: Properties purchased
* 80 feet: Depth of underground retainer wall being built to repair landfill
* 11 miles: Length of underground walls within walls in the 2-mile enclosure
* 14,000: Tons of coal consumed daily when Kingston plant is at full power
* 450-300: Workers onsite have ranged from 450 to 300 each workday. Another 300 people work inside the Kingston plant making electricity.
HARRIMAN, Tenn. - Nearly every Saturday morning for four years, Robert M. "Bob" Deacy has gone to a particular spot on Swan Pond Circle to sit with his coffee and watch workers clean up one of the nation's largest industrial environmental accidents.
Deacy is a Tennessee Valley Authority senior vice president and executive in charge of the $1 billion Kingston Ash Recovery Project.
His reflection site is ground zero, where four years ago today a 60-foot wall of toxics-laden ash spilled across the Emory River and over nearly 400 acres of a rural residential community.
Today, what was once the resulting gray moonscape of "ashbergs" is a mix of greened-up sculpted swales and smooth gray berms.
But just wait two more years.
"When it's done, it will look like a big grassy knoll," Deacy said.
And eventually, Roane County will have a nearly 400-acre park here with boat docks and ball fields.
That day will signify the Kingston ash spill's final cleanup -- give or take about 30 years and at least $10 million worth of environmental monitoring.
Even now, the before, then and now photographs make a stunning comparison.
Before the spill, the area was a little residential paradise overlooking a lazy river inlet with what longtime residents and newcomer Oak Ridge retirees called the best fishing in East Tennessee.
In the stark morning light of Dec. 22, 2008, it had become a gray moonscape of "ashbergs" that had obliterated the river inlet and left boat docks mangled and surrounded by quicksandlike muck.
It choked a spring that fed nearby wells and became a new dam that -- with the toxins from the ash-covered pastureland -- called into question the safety of cattle and horse grazing.
Deacy, also tasked in the spill's aftermath with converting to dry storage all of TVA's other wet ash storage operations at Kingston and the agency's other coal plants, said TVA has made a commitment to restore the area.
"Our goal is to make sure this never happens again, and we want to put it back [in Harriman] as good or better than it was," he said. "Pretty soon we'll be ready to plant flowers, bugs and bunnies."
No more community
As with any disaster, there is no way simply to turn back time.
Four years ago, the man sleeping inside the crumpled house thought he'd lived through an earthquake. So did other nearby residents.
No one died, but in the frigid dawn, emergency workers and Tennessee Valley Authority officials would come to grips with the reality that 5.4 million cubic yards -- 1.2 billion gallons -- of 50-year-old coal sludge had just obliterated a river tributary and oozed onto nearly 400 acres of land on the river's far side.
Three homes were destroyed immediately, and eventually TVA would buy out 150 residents on 181 tracts of surrounding land.
These were people worried about their health and property values as TVA contractors worked the delicate balance of moving ash over and over to dry it enough for removal and rail shipment to an Alabama landfill.
The trick was to do this while still keeping the ash wet enough not to create deadly blowing ash laced with cancer-causing silica particles -- legacy waste of making electricity.
The homes since have been razed. Many of the once-vocal and angry residents, like Terry and Sandy Gupton with their Rocky Top Farms cattle operation, have moved away.
A condition of the settlements with TVA included no-lawsuit and no-comment clauses.
One by one, the home-owners packed up and left, saying they had come to fear that even if they survived health threats they could barely pronounce, their land values and financial futures could not.
The Guptons were among the last to leave, moving their farm and registered herd of cattle in late 2010 to Crossville, Tenn.
"We bought a farm that had comparable open land and have built the buildings, fences and water system. Moving a farm operation is not an easy task, but we are happy to be moving on with our life," they wrote in an email this week.
The spilled ash's pollution impact in the water proved to be an equally tricky balancing act.
The ash waste contains arsenic and selenium and other chemicals in toxic measures. Researchers from two universities and the Tennessee Aquarium Conservation Institute have documented fish with severe abnormalities in river reaches affected by the spill.
TVA officials say they continue to spray the ash piles to keep dust down, and water that flows off the area is treated so the water and air are safe for people and will become more so as the project is completed.
TVA, with state and federal oversight, has had to make sure air, land and water eventually are cleaned up.
The utility has taken thousands of air monitoring and water samples and sent 3.5 million cubic yards of recovered ash to a landfill in Alabama.
Another 2.8 million cubic yards will be replaced into the dredge cell -- environmental-speak for the wet-ash landfill -- when the construction of a new 2-mile perimeter wall is complete.
And 500,000 cubic yards of ash will be left on the bottom of the Emory and Clinch rivers because TVA, state and EPA officials fear that moving it will disturb "legacy" cesium pollutants from Oak Ridge's Manhattan Project. Regulators have said nature and the river's flow can cover and handle that amount of ash.
Craig Zeller, the cleanup project oversight manager for the U.S. Environmental Protection Agency, said the massive project -- including the construction of a new wall around the failed landfill -- is about two months ahead of schedule.
"We're probably about 60 percent done with the wall," he said "and about 90 percent done with the excavation of the ash" that was on the land.
The wall is actually several walls within walls and extends 80 feet deep into the bedrock below the river's level. It forms two circles, but workers actually are building 11 miles of walls when all the layers are counted, Zeller said.
"It's designed to withstand a 6.2 [magnitude] earthquake from the East Tennessee fault and a 7.6 quake from the New Madrid fault," he said. "Once we get the wall done, we've got to line the dredge cell and get all the ash back inside the wall."
Once that's done, workers will cover the landfill with two feet of clay that is being moved from what once was the Gupton's farm. When it's all seeded, it will be Deacy's "grassy knoll."
Deacy and Zeller said they hope the boat launches and some of walking trails will be completed and open this summer.
"Finally we can see the light at the end of the tunnel," Zeller said. "The plan is for the whole area to become a recreational park. That's an important piece to both TVA and EPA, because it's what we're leaving behind."