High levels of benzene gas were discovered at the smoldering Bridgeton Landfill over the weekend, the state attorney general said Monday.

Chris Koster filed an injunction Monday in St. Louis County Circuit Court against the landfill’s owner, Republic Services, seeking “more aggressive landfill management” by the company and more money to pay for the state’s monitoring of the site.

“The release of benzene by Republic into the environment at the Bridgeton Landfill is unacceptable,” Koster said in a statement. “Despite the order Republic agreed to more than a year ago, the company still does not appear to have the situation under control. My office is asking the court to compel Republic to take additional steps to prevent any such future release of hazardous material into the air.”

A Missouri Department of Natural Resources inspector on Saturday found elevated levels of the cancer-causing chemical at the perimeter of the landfill that were “substantially in excess of site-specific standards” established by the state health department, according to Koster.