All four men worked for a subcontractor that pours concrete foundations.
Danny Flanders, a spokesman for the Atlanta Botanical Garden, said the garden has placed a commemorative plaque in honor of the workers on site at a memorial garden.
"We certainly have sympathy for the families of those workers," Flanders said. "And we're sure these families want answers just like we all do."
Phil Torchio, president of Williams Erection Co., a defendant in the case, said he was aware of the lawsuits. "Everybody here feels terrible about everyone who was injured and certainly Mr. Chupin who was killed," he said, declining further comment.