MOBILE, Ala (WKRG) — The Alabama Department of Environmental Management has ruled in favor of Alabama Power, approving its plan to deal with coal ash pits at the Barry Steam Plant in north Mobile County.

Just a few feet off the Mobile River, Alabama Power over the last several decades has dumped 21 million tons of coal ash — the by-product of burning coal — into an unlined holding pond. Federal law now bans the process, and utilities must dispose of the ash.

ADEM says Alabama Power can drain the water from the 30-acre pit, leave the coal residue, and cap it.

Environmentalists are vowing to continue their fight.

“It’s going to leave 21 million tons of coal ash in an open pit on the side of a powerful, flood-prone Mobile River,” said Cade Kistler of Mobile Baykeeper. “It’s a bad decision.”

Mobile Baykeeper had advocated for Alabama Power to truck the sludge away from the river, across highway 43 to a lined landfill.

That option, however, would cost three times the $2 billion dollars  Alabama Power will pay to cap the pond.

Kistler says Baykeeper will fight the ruling, possibly in court, and elsewhere.

“This is not the end,” he said. “I’ll say that. We’re going to be working with public officials and looking at all our options to see what we can do, because this is irresponsible.”

Environmentalists say the capped pond will be a ticking time bomb, that flooding or storm surge from a major hurricane could breach the pond and send the slurry into the Mobile River, destroying the ecology and 20 miles downstream at the port, the economy.

That’s just what happened in 2008, near Kinston, Tenn., where it took seven years to clean up after a dyke failed.

Virginia and North Carolina  have passed laws against what Alabama Power wants to do here

“Alabamians are being treated differently and our environment, our economy, and our communities deserve the same as our neighbors in other southeastern states,” Kistler said.