Kiener Plaza is likely to be the first portion of the Gateway Arch project to be completed.
Those familiar with the project say it's slated for completion in the fall of 2013.
The plan for the Plaza includes a performance pavilion, an eating venue, seating, and water features.
Walter Metcalfe with the CityArchRiver 2015 Foundation, the group that sponsored the design competition, said work on Kiener Plaza can move forward more quickly because it's not part of the National Park.
"We don't have all the compliance and permitting processes that are required on the National Park property, which is what we're going through now, value analysis and environmental assessments," Metcalfe said.
The Gateway Mall Conservancy, which oversaw the City Garden project, will take the lead in the redevelopment of Kiener Plaza, as well.
The projected cost for Kiener is not yet know, but the entire Arch redevelopment is expected to cost 578 million dollars and be completed in October 2015.