KNOXVILLE, TN (News Sentinel) -- A federal judge has ruled that TVA is liable for the failure of a storage cell which led to a massive ash spill in Roane County .

In a written opinion issued this morning, U.S. District Judge Thomas Varlan said that "TVA is liable for the ultimate failure of North Dike which flowed, in part, from TVA's negligent nondiscretionary conduct."

The ruling also said that while plaintiffs' claims of negligence, trespass, and private nuisance will proceed to Phase II proceedings, but that plaintiffs' claims of negligence per se will not and will be dismissed.

The ruling said that in Phase II, each plaintiff must prove the elements of his or her respective negligence, trespass, and/or private nuisance claims by a preponderance of the evidence.

The litigation centers on the massive coal ash spill that befouled the Emory River in December, 2008, after the failure of a giant outdoor storage cell at TVA's Kingston Fossil Plant, in Roane County.

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