GFL Environmental Inc. (TSX:GFL) is considering the sale of a stake in its infrastructure arm, people with knowledge of the matter said, in what could be one of Canada?s largest infrastructure deals this year. The company is seeking a valuation of as much as CAD 5 billion ($3.7 billion) including debt for the affiliate, known as Green Infrastructure Partners Inc., the people said. The stake sale is attracting initial interest from potential investors including General Atlantic L.P., Energy Capital Partners, LLC and Neuberger Berman Group LLC, the people said.