CHESTERFIELD, Mo. – The owners of Chesterfield Mall have set a date for when mall will close and work could start on a new $2 billion project to replace it. All tenant leases at the mall will end Aug. 31, and demolition of the mall could start as soon as the fall, ahead of the mixed-use Downtown Chesterfield project, said Tim Lowe, senior vice president of leasing and development for The Staenberg Group, the owner of the mall and developer of Downtown Chesterfield.