KNOXVILLE (AP) — A federal judge won't order a new trial in a case that blames a contractor for the medical problems of workers who cleaned up a massive coal ash spill in East Tennessee.

The suit against Tennessee Valley Authority contractor Jacobs Engineering claims the firm failed to protect workers from toxins. Testimony at trial included evidence that Jacobs employees took dust masks away from workers and threatened to fire them.

The trial was split into two phases. Jurors in November found that Jacobs' actions were capable of causing the workers' medical problems.

Jacobs asked for a new trial, but on Thursday Chief U.S. District Judge Thomas Varlan denied that motion.

The injuries of individual plaintiffs will be considered in the second phase, if it happens. Varlan has ordered the parties to attempt mediation first.