One of the Bay Area’s largest metal recyclers has been illegally discharging dangerous chemicals into the San Francisco Bay, federal officials announced Tuesday.

Citing the federal Clean Water Act, the U.S. Environmental Protection Agency ordered Sims Metal Management, located at the Port of Redwood City, to take action to stop the pollution after inspections last March found evidence that the company was unlawfully discharging of PCBs, mercury, lead, copper and zinc into San Francisco Bay.

The South Bay facility is home to one of the largest metal shredders in the Bay Area, and regularly shreds entire cars before exporting the metal overseas.

“The EPA is committed to protecting the Bay by ensuring compliance with environmental permits,” Jared Blumenfeld, EPA’s Regional Administrator for the Pacific Southwest, said in a prepared statement. “Companies such as Sims Metal Management, engaged in recycling our finite resources, must abide by the Clean Water Act.”

According to records provided to the EPA by the Port of Redwood City, from July 2010 to June 2011, 20 large vessels, picked up and transported an average of 22,000 tons of shredded material from the facility bound for global destinations including China.

The largest transport during the specified time period was 35,000 tons of shredded material.

Last March, the EPA inspected the facility to determine compliance with their Industrial Storm Water Permit.

During the inspection, enforcement officers found evidence at the facility’s shipping and rail receiving areas that pollutants have been discharged to Redwood Creek, a direct tributary to San Francisco Bay.

In August, the EPA again inspected the facility and took samples of debris and soils in the areas that flow to San Francisco Bay, where the facility conducts shipping and receiving activities. The results of the samples demonstrated elevated levels of PCBs, mercury, lead, copper and zinc.

Federal officials said Sims Metal Management acknowledged received of the U.S. EPA Order on December 21, 2011.

The order requires Sims to submit a revised storm water pollution prevention plan and to update monitoring and sampling within 30 days of the order; and to develop and implement storm water pollution counter measures.

The EPA’s order also requires Sims Metal Management to develop and submit a plan within 90 days to eliminate these discharges to Redwood Creek within one year.

The company must: sample storm water discharges monthly throughout the winter and spring; revise their storm water pollution prevention plan to update monitoring and sampling; and develop and implement storm water pollution counter measures for all areas of activity.

Sims is working cooperatively with the EPA to address requirements of the order.