The U.S. Environmental Protection Agency said the plant failed to comply with emission limits in its state operating permit and in state regulations on opacity, which is the amount of light obscured by particulates such as smoke, dust and ash. The agency also cited the plant for excessive releases of nitrogen oxide, carbon monoxide and sulfur dioxide.

The EPA´s said its findings of violations are preliminary. Wyandotte officials have 30 days from receipt of the notice to meet with the EPA to discuss resolving the allegations. The EPA may issue a compliance order to resolve the alleged violations, assess an administrative penalty or bring a lawsuit.