Operations in the cathode mixing area will remain paused until cleanup is complete and the area “has been inspected for damage and deemed safe,” said Burdette, adding that Ultium has brought in a third-party company to assist with the cleanup.
Burdette did not provide an estimate on how long the cleanup could take. It is also unclear how the leak has affected battery cell production.
Ultium reported the incident Monday to the U.S. Labor Department’s Occupational Safety and Health Administration, which also has opened an investigation into the matter.
The chemical leak and federal investigation were first reported by The Detroit News.
OSHA spokesperson Scott Allen said the agency is collecting information from Ultium “as to the details of what happened, what actions they took to address them and whether employees are still at risk.”
Based on the information received, OSHA will then determine whether employees were exposed to a significant hazard, whether actions taken by Ultium were appropriate and whether there is enough information to establish a potential violation of workplace safety and health standards to warrant citations, Allen said.
The agency is still investigating the extent of exposure to the chemical leak, which contained N-Methylpyrrolidone (NMP), a solvent used for various purposes including cathode manufacturing. NMP can enter the body through skin contact or inhalation via vapor or spray droplets.
Overexposure to NMP can irritate the eyes, skin, nose and throat and affect the central nervous system and brain, causing symptoms of drunkenness similar to the effects of drinking alcohol.
OSHA could invoke the “General Duty Clause,” which requires an employer to provide its employees with a workplace free from recognized hazards that could cause death or physical harm, if workers are becoming “seriously ill from NMP,” Allen said.
OSHA has six open inspections at Ultium’s Warren plant and five closed inspections.
To date, the company has paid $31,078 in fines for violations of OSHA workplace laws. In some cases, penalties were reduced or waived, Allen said.
In December, the UAW won an election at the Warren plant — marking the first and only unionized battery cell manufacturing plant in the U.S. — with workers voting 710-16 in favor of union representation. A contract is still being negotiated.
The union criticized conditions at the plant in a white paper released in July, arguing its workers have “reported serious health and safety problems” and face “hazardous conditions and low pay.”
Ultium, which is a separate legal entity and independent employer from GM and LG, said in a letter to Sen. Sherrod Brown, D-Ohio, last month that it remains “committed to bargaining a fair agreement that allows Ultium Cells, our employees and the UAW to succeed in the EV future.”