MODESTO  (AP) — Two corporations that owned the Post cereal brand have agreed to pay $635,000 in fines to settle allegations that they failed to prevent air pollution from a Modesto plant where Grape-Nuts, Banana Nut Crunch and other products were made.

The U.S. Environmental Protection Agency announced Friday that Post Holdings, Inc. and Ralcorp Holdings Inc. are being penalized because federal investigators found that cereal coaters, dryers and other equipment at the 282,000-square-foot plant emitted chemicals that play a role in creating smog.

The EPA says Post has since spent $1.4 million on equipment to control the emissions.

However, Post Holdings announced in April that it plans to close the Modesto plant by September 2014. The plant employs 140 people and is one of the largest taxpayers in Stanislaus County.