More than 75 people packed a Doraville town hall meeting Tuesday night with questions about the proposed redevelopment of an old General Motors factory site.

Many residents asked city officials how some $75 million in public money would be spent to improve streets, bridges, sewers and water lines.

Mayor Donna Pittman told them the project was a rare opportunity to transform an unused 162-acre property into a place where people can work, live and play.

She suggested that the site could hold a new high school, sports fields, a medical center, housing, stores and business offices.

“This is going to make history. This is going to put Doraville on the map in a very positive way,” Pittman said. “The city is on the cusp of a vast revitalization.”

The sale of the site from GM to the developers, Integral Group and Macauley + Schmit, could be completed in August or September, said City Manager Shawn Gillen. Terms of the sale haven’t been disclosed, but GM had been seeking $60 million for the property, which hasn’t been used since the plant shut down in 2008.

Gillen explained to the audience, which included mayors from surrounding cities, that taxpayer money would only be used for infrastructure improvements, and public funds wouldn’t supplement the property’s sale or development costs.

The city plans to issue bonds to help pay for infrastructure, and those bonds would be paid off by the increase in property tax revenue brought in by the expected revitalization of the area, Gillen said.

The result should increase property values in the surrounding area, he said.

“More people are going to want to live here. They’re going to want to live closer to where they work,” Gillen said.

After the sale of the property is completed, the Doraville City Council will consider whether to approve a redevelopment plan.

It would take at least 12 to 18 months to level the property before new construction begins, Gillen said.