(Reuters) - Residents living near landfill sites in the St. Louis area where radioactive waste has been stored filed lawsuits on Tuesday seeking compensation, claiming negligence in handling materials they said were some of the most dangerous on Earth.

Two lawsuits seeking class action status were filed at St. Louis County court for sites that included the West Lake Landfill in Bridgeton, Missouri, and an area near the Coldwater Creek in the county.

Among the 10 defendants are Republic Services, Exelon Corp and the Cotter Corp. Officials from those companies were not immediately available for comment.

“Defendants treated these hazardous, toxic, carcinogenic, radioactive wastes with about the same level of care that a reasonable person might give to common household garbage, dumping it without authority from the State of Missouri and in violation of law,” the lawsuits contend.

The suits did not state an amount being sought by the plaintiffs.

The history of nuclear waste in the St. Louis area dates back to the U.S. atomic bomb program from World War Two and spans an array of nuclear processing facilities, storage sites, material transfers and suspected leaks along the way.

The U.S. Environmental Protection Agency has deemed some of the St. Louis-area places that were a part of that history “Superfund” sites, placing them among highly polluted areas that are a national priority for clean-up.

The West Lake site, originally used for agriculture, became a limestone quarry in 1939. But starting in the 1950s, portions of the area were used to dispose of municipal refuse, industrial wastes and construction debris, the EPA said.

In 1973, some 8,700 tons of leached radioactive barium sulfate from the Manhattan Project, the World War Two-era atomic bomb-development program, were mixed with 38,000 tons of soil used to cover trash dumped at the site, according to the EPA.

In 1990, the landfill and neighboring waste-disposal facilities occupying a total of 200 acres (80 hectares) were designated by the EPA as a single Superfund site.