The Fort Smith manufacturing plant will undergo a $145 million dollar expansion that will add at least 120 jobs in the Arkansas River Valley area. Credit Talk Business & Politics Gov. Asa Hutchinson and officials with Mars Petcare were in Fort Smith on Friday to announce a $145 million expansion of the company’s plant at Chaffee Crossing that will create more than 120 jobs. Officials with Mars Petcare – based in Brussels, Belgium, with a U.S. headquarters south of Nashville, Tenn. – announced in November 2007 they would build the Fort Smith pet food production and packaging plant, and the $80 million facility opened in September 2009. The average annual salary at the plant was then estimated at $35,300.