KNOXVILLE - Plaintiff attorneys who contend the Tennessee Valley Authority should pay damages for the Kingston Plant coal ash spill Friday cross-examined a TVA consultant who testified he was hired to find the "mechanics" of the cause, not to place blame.
Geotechnical engineer William H. Walton was on the witness stand for a second day at the federal bench trial on damage lawsuits by property owners who contend TVA negligence in training, operations and construction caused the December 2008 disaster.
Walton testified Friday that TVA hired him as AECOM USA Inc.'s chief investigator to determine "why the structure failed." He said he was not hired to determine any TVA management or operational problems.
"I conducted a probable failure modes analysis," Walton said of his work investigating the spill and preparing the report in 2009.
The nation's largest public utility is trying to avoid lawsuit payouts from the spill of about 5.4 million cubic yards of ash in a breach of an ash pond dam into the Emory River and on a Roane County river community about 35 miles west of Knoxville. Along with a $1.2 billion cleanup that is costing ratepayers an average of 69 cents a month each until 2024, TVA has purchased 889 nearby acres for $46.6 million.
TVA previously said it has purchased more than 180 properties and settled more than 200 other claims from people living near the spill.
Walton answered questions about his report, which partly blamed the storage pond spill on a "slime layer" of ash deep underneath the surface. His report said the slime tended to move and add hydraulic pressure to the dikes. He described it as being like yogurt, seeming to be stiff until it is stirred. He also testified about new monitoring equipment that TVA is installing at its coal ash facilities.
The chief of TVA's watchdog agency, TVA Inspector General Richard Moore, has criticized Walton's report, saying it did not address TVA failures to heed advance warnings about the storage facility and did not take into account any management issues as a possible cause.
Moore has testified that he stands by his criticism that the consultant's report failed to consider management practices and gave too much weight to the slime layer.
The inspector general has said that the finding on the ash slimes tended to reduce the "legal liability" of TVA management. Moore's report also said TVA management's decision to allow its lawyers to hire the consultant and narrow his focus for the "root cause" study predetermined a choice "between accountability and litigation strategy."
Another study said the spill "could have possibly been prevented" if TVA had heeded concerns about the stability of the ash pond previously raised by TVA employees and consultants.
"I don't know that I've had time to think about what they could have or should have done," Walton testified.
The Environmental Protection Agency has described the spill as "one of the worst environmental disasters of its kind" and is trying to decide if the coal ash, which contains toxins such as mercury, selenium and arsenic, should be regulated as hazardous. The byproduct of generating electricity with coal can be dumped in landfills along with household garbage.
Walton, whose study for TVA cost $3 million, testified that he has since gotten other TVA contracts and is being paid about $180,000 for his testimony as an expert and for work preparing for his trial appearance.
U.S. Judge Thomas Varlan ruled before the trial that TVA, as a federal agency, is protected from some liability claims. TVA also contends that under Tennessee law it has no legal duty to keep its reservoirs and shorelines safe for the plaintiffs' recreational use and enjoyment.
TVA has said the plaintiffs have not shown that ash particles were transmitted to their properties in "concentrations sufficient to cause property damage and/or personal injury or to constitute a taking."
While hundreds of people are seeking damages in the court fight, this first trial and another trial set Nov. 1 deal only with liability. If TVA is found to be liable, any damage amounts will be decided later.
TVA supplies power to about 9 million customers in Tennessee, Alabama, Mississippi, Kentucky, Georgia, North Carolina and Virginia.