Associated Press - July 29, 2009 4:54 PM ET
DALLAS (AP) - The largest U.S.-owned cement company has filed a lawsuit alleging unconstitutional discrimination from a large Dallas suburb.
That's after Plano city officials decided to buy cement made in a more environmentally friendly process than that used by Ash Grove Cement Co.
The Overland Park, Kan.-based Ash Grove filed suit against Plano in a federal court in Dallas on Wednesday. It alleges Plano's move is unconstitutional and violates state competitive bidding laws.
Ash Grove also has sued Dallas, Fort Worth and other local governments for favoring cement from "dry kilns" instead of older "wet kilns" that pollute more.
Ash Grove's lawsuit asks that the city of about 264,000 to stop the preferential purchasing.
Plano's city attorney did not immediately return a message for comment Wednesday.