KNOXVILLE, Tenn. (AP) – A federal judge has ordered mediation between the Tennessee Valley Authority and Roane County residents suing over a massive coal ash spill in 2008.

The Knoxville News Sentinel reports that on Monday, U.S. District Judge Tom Varlan gave the two sides 120 days to reach a settlement.

Varlan said he would consider allowing more time for mediation if needed. If issues remain after mediation, the case will proceed to trial.

Varlan already found TVA liable after the Kingston Fossil Plant dumped 5.4 million cubic yards of coal ash sludge into the Emory River and surrounding land.

About 872 plaintiffs are suing the federal utility for damages. Plaintiffs asked the court to order mediation.

Jeff Friedman, one of their attorneys, told the paper, “We are confident progress can be made. We can whittle this case down if not solve it outright.”

TVA attorney James Chase said the utility did not oppose mediation but wanted to hold off. Concerns include the fact that the statute of limitations for damage claims has not expired, so new claims could still come in.

TVA had proposed that an initial round of plaintiffs be allowed to go to trial and through the appeals process, if necessary, before mediation.

But Varlan said mediation should at least be tried. He said he did not believe it would complicate the process.