Members of the United Mine Workers of America plan to march from the Crowne Plaza Hotel at 4th and Pine streets to Peabody Energy's headquarters at 701 Market St, protesting allegedly unpaid health care benefits by Peabody, Arch Coal and Patriot Coal.
Peabody Energy spun off Patriot Coal in 2007.
Patriot filed for Chapter 11 bankruptcy protection last July.
Peabody reported a loss of $575.1 million in fiscal 2012, compared with a profit of $946.3 million in 2011.
According to the St. Louis Business Journal, UMWA president Cecil Roberts said: “Peabody and Arch executives are shifting around like sand on a beach, trying to evade their obligations to the workers who made the company wealthy.
"We will not rest until we win justice for the workers who were promised health care benefits in exchange for a lifetime of hazardous work,” he said.