WASHINGTON (Reuters) - The U.S. Environmental Protection Agency said on Tuesday it was assessing two Superfund environmental cleanup sites in Nebraska and Missouri that were affected by recent flooding.

The Nebraska Ordnance Plant in Mead and the Conservation Chemical Corporation site in Kansas City are being monitored, the agency said in a statement, adding that “no releases of hazardous contaminants caused by flooding at these sites have been identified.”

At the Nebraska site, floodwaters rendered portions of the site temporarily inaccessible and forced a two-day shutdown of the groundwater treatment plant and extraction wells, EPA said. The treatment plant and the wells are running again, it added.

In Kansas City, the Conservation Chemical Corporation site partially flooded when the nearby Missouri River topped its banks, the agency said. To deal with the floodwaters, the pumping rate of the site’s groundwater treatment system was increased, EPA said.

The Superfund program, started in 1980, is intended to identify and clean up some of the nation’s most polluted sites, which now number more than 1,300 across the country. But it has been criticized over the years for slow efforts.