A coal train stops near the White Bluff Plant near Redfield, Ark. in 2014. Entergy Arkansas agreed to eventually stop using coal at this and another plant under a settlement with environmental groups, but a dark money nonprofit funded by Wyoming is pushing to keep them operating.

FILE – In June 2, 2014 file photo, a coal train stops near White Bluff power plant near Redfield, Ark. Entergy Arkansas says it will eventually stop using coal at two power plants and shut down a natural gas plant under a settlement reached with environmental groups. Entergy says it will stop using coal no later than the end of 2028 at its White Bluff plant and by the end of 2030 at its Independence plant. (AP Photo/Danny Johnston File)