AT&T Inc (T.N) will pay $52 million in civil penalties and environmental compliance as part of a settlement with California over illegal dumping of hazardous waste but won't be required to clean up the resulting contamination, state officials said on Thursday.

State officials said it marked the first enforcement action in California against a telecommunications company for mishandling of electronic waste. The settlement must still be approved by the Alameda County Superior Court, where it was filed.

Investigators cited AT&T for illegally disposing of hazardous wastes and other materials at more than 235 of its warehouses and dispatch centers across the state over a nine-year period.

Inspections of trash dumpsters at those facilities by county prosecutors and state regulators found the company was routinely sending hazardous materials to local landfills not permitted to receive such contaminants.

The wastes in question consisted primarily of discarded electronic equipment, batteries and aerosol cans, as well as "certain liquids and gels" used by AT&T service technicians, the state said in a statement.

"This settlement holds AT&T accountable for unlawfully dumping electronic waste," state Attorney General Kamala Harris said.

AT&T admitted no wrongdoing as part of the settlement, nor is it compelled to remove any of the waste it was found to have dumped illegally, said David Beltran, a spokesman for Harris.

But the judgment also expressly does not release AT&T from any liability for contamination in the event the Dallas-based company is named in a lawsuit seeking damages, Beltran said.

AT&T officials were not immediately available for comment.

Verizon Communications Inc (VZ.N) has acknowledged that it was the subject of a similar investigation by California earlier this year.

Under the agreement with AT&T, the company will pay $23.8 million in civil penalties and other costs and spend $28 million more over the next five years to carry out "enhanced environmental compliance measures" required by the settlement, the state said.

Consumer advocate Liza Tucker from the nonprofit Santa Monica-based group Consumer Watchdog criticized the settlement as falling short by not requiring AT&T to undertake a costly cleanup necessary to ensure public health and deter similar dumping by others.

"They're being fined what amounts to chump change for a company like AT&T, and the public is not going to be protected in the end because wherever they've illegally disposed of that waste, it's going to stay there," she said.