U.S. Magistrate Bruce Guyton recommended denying the class action status sought by attorneys for some of the 457 plaintiffs spread among about 50 current lawsuits, and for any others waiting to sue.

Since the Dec. 22, 2008, spill of 5.4 million cubic yards of toxin-laden sludge in the Emory River and on privately held land beside TVA's' Kingston Plant, the utility has negotiated buyouts of more than 170 properties and is continuing a cleanup that is projected to cost $1.2 billion.

"A class action is not superior to other available methods for fairly and efficiently adjudicating these cases," Guyton said in his recommendation.

"The diversity of claims in these cases and the danger of plaintiffs being excluded from asserting their individual claims for personal injury, medical monitoring, or other claims undermine the adequacy of representation" in a class action, the magistrate's recommendation said.