El Paso Electric spokeswoman Teresa Souza said the lawsuit is an old dispute about some ambiguous language in an air permit that has been clarified. She said the plant is in compliance with the air permit.
Environment Department spokeswoman Marissa Stone said that the department issued a compliance order to El Paso Electric for excess emissions violations about two years ago and those violations have not been resolved.
Stone added that the company's recent emissions also are in excess of its permit limits.
As part of the lawsuit, the Environment Department claims El Paso Electric violated more than 350 of the maximum emission rates for oxides of nitrogen, carbon monoxide and sulfur dioxide and failed to report deviations from the maximum emission rates.