I don't see how TVA can argue this. Can anyone else?

The basic concept of citizens not being able to sue their own government for doing what it democratically opted to do makes sense to me. The problem here is not so much with the legal reasoning as with the nature of TVA itself. The government really shouldn't be operating coal plants. Unfortunately, part of TVA's mandate was to support itself through power sales, so its power generation operations would seem to fall under immunity.

With the NC case, it was not merely operating coal plants that got TVA in trouble; it was their failure to install scrubbers and other pollution-reduction devices. They were acting contrary to democratically enacted regulations, so they blew their immunity. Some sort of similar disregard for public policy will probably need to be proved in this case, but since EPA failed to enact reasonable standards for coal ash storage, that will be hard. Of course, with all the prior warnings TVA had about the risk of these ponds failing, proving disregard may not be impossible.

TVA's brief is well written and its going to be tough to get past. TVA used this same defense in the suit NC filed against it for polluting NC's air. In NC, they lost in the district court and took an interlocutory appeal to the 4th Circuit, where they lost again. That case was tried in December and NC won, with the district court ordering TVA to fix the problem. However, the 4th Circuit also cited cases from the 6th Circuit where the discretionary function doctrine was applied. In its brief in our case, TVA cites a recent case where Judge Varlan dismissed claims against TVA under the discretionary function defense. Judge Varlan is going to allow us to take some depositions of TVA personnel to use in our response to TVA's motion, which is due in June.