WASHINGTON — Wal-Mart Stores Inc. pleaded guilty in cases filed by federal prosecutors in Los Angeles and San Francisco to six counts of violating the Clean Water Act by illegally handling and disposing of hazardous materials at its retail stores across the U.S., according to a press release.

The Bentonville, Ark.-based company also pleaded guilty in Kansas City, Mo., to violating the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) by failing to properly handle pesticides that had been returned by customers at its stores across the country, stated the release.

As a result of the three criminal cases brought by the Justice Department, as well as a related civil case filed by the Environmental Protection Agency (EPA), Wal-Mart will pay approximately $81.6 million for its unlawful conduct.

Coupled with previous actions brought by the states of California and Missouri for the same conduct, Wal-Mart will pay a combined total of more than $110 million to resolve cases alleging violations of federal and state environmental laws, noted the release.

According to documents filed in U.S. District Court in San Francisco, from a date unknown until January 2006, Wal-Mart did not have a program in place and failed to train its employees on proper hazardous waste management and disposal practices at the store level.

As a result, hazardous wastes were either discarded improperly at the store level — including being put into municipal trash bins or, if a liquid, poured into the local sewer system — or they were improperly transported without proper safety documentation to one of six product return centers located throughout the U.S.

“By improperly handling hazardous waste, pesticides and other materials in violation of federal laws, Wal-Mart put the public and the environment at risk and gained an unfair economic advantage over other companies,” said Ignacia S. Moreno, assistant attorney general for the Justice Department’s Environment and Natural Resources Division. “Today, Wal-Mart acknowledged responsibility for violations of federal laws and will pay significant fines and penalties, which will, in part, fund important environmental projects in the communities impacted by the violations and help prevent future harm to the environment.”

Read the entire press release here.