The Justice Department said on Friday it granted antitrust approval for Waste Management Inc's purchase of Deffenbaugh Disposal, Inc. Waste Management Inc,, a $14 billion a year garbage and recycling giant, agreed to sell assets in Kansas and Arkansas in order to win approval for the $405 million deal, the department said. The divestitures were focused on small container waste services, or collecting solid waste from offices and apartment buildings, the department said.