Exide demonstrators

Members of environmental groups rally outside the Exide Technologies battery recycling smelter in Vernon demanding cleanup of the plant in April. (Al Seib / Los Angeles Times / April 14, 2014)

A federal grand jury is investigating Exide Technologies over emissions of harmful pollutants from its Vernon battery recycling plant, according to a financial disclosure filed this week.

Exide on Aug. 8 received a “grand jury subpoena from the Department of Justice in the Central District of California in connection with a criminal investigation involving its Vernon, California recycling facility,” according to a Securities and Exchange Commission filing.

The subpoena requested “documents relating to materials transportation and air emissions,” in an investigation targeting the company and “certain unidentified individuals,” according to the filing.

News of the federal investigation is the latest in a series of troubles for the lead acid battery smelter, which in recent years has been under scrutiny by state and local regulators and drawn outrage from community groups and elected officials for emitting too much lead and arsenic. Lead acid batteries are used in automobiles and industrial applications.

A March 2013 health study found that the facility’s arsenic emissions posed an increased cancer risk to more than 110,000 people across southeast Los Angeles County.

The facility, one of only two lead acid battery smelters west of the Rocky Mountains, has been closed for months as it upgrades its pollution controls to comply with local air quality regulations. The plant, which can process about 25,000 batteries a day, has been cited repeatedly in recent years for excessive lead emissions.

A statement issued by the Milton, Ga.-based company confirmed “that it has been identified as a target of the grand jury investigation, and that the company intends to cooperate with the investigation.”

A spokesman for the U.S. attorney's office in Los Angeles refused to comment. Grand jury proceedings are secret by law.

The Vernon plant closed in March because it was unable to comply with strict new rules adopted by the South Coast Air Quality Management District. Under an agreement reached with the air district in July, Exide agreed to remain closed until it upgrades its pollution control equipment at an estimated cost of $5 million.

Crews hired by Exide on Monday began cleaning lead-contaminated soil from two homes near the plant after tests conducted last fall found elevated levels of the harmful metal in dozens of homes and a preschool in nearby Boyle Heights and Maywood.

The federal probe was welcome news to community activists who have sought the permanent shutdown of the plant and have demanded an extensive cleanup of airborne lead that has been deposited in the soil over many years.

"Hopefully this is another way to bring Exide to accountability," said Msgr. John Moretta of Resurrection Catholic Church in Boyle Heights. "You have a company that has a whole list of violations and, year after year, they pay a fine and they are allowed to continue working."

The Vernon plant has operated since 1922 and was taken over by Exide in 2000.

On Tuesday, Los Angeles County supervisors wrote a letter to Gov. Jerry Brown criticizing as “piecemeal” the testing and cleanup of nearby homes overseen by the California Department of Toxic Substances Control. The state agency has allowed the company to operate for decades without a full permit.

The South Coast air district in January filed a lawsuit against Exide in Los Angeles County Superior Court seeking up to $40 million for a series of air quality violations.

Exide, one of the world’s largest producers of lead acid batteries, filed for Chapter 11 bankruptcy protection last year.

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