An appeal by the nation's largest utility says a federal judge abused his discretion by ordering a massive coal ash cleanup at a Tennessee power plant based on scant evidence of harm done.

In the 6th U.S. Circuit Court of Appeals filing late last month, the Tennessee Valley Authority argues the Clean Water Act shouldn't have been applied in the case over the Gallatin Fossil Plant.

TVA's filing also says Tennessee environmental regulators declined to put permit limits on underground leaks into groundwater from the ash complex.

In August, a federal judge ordered the ash excavated and removed, saying it's leaking pollutants into the Cumberland River in violation of the Clean Water Act with scant evidence of harm.

The federal utility says it's taking steps to comply during the appeal.