Atlanta taxpayers could be on the hook for $13 million to help finance the sale of Fort McPherson to Tyler Perry Studios.

On Monday, the McPherson Implementing Local Redevelopment Authority — the civilian authority overseeing the former U.S. Army post’s future — asked the Atlanta City Council to back a letter of credit that could commit the city to buying $13 million worth of land there in coming years.

The original deal — brokered by Mayor Kasim Reed — to sell parts of the Army post to Perry was supposed to be simple: The filmmaker would stroke a check for $30 million, with that money to be used by the civilian authority to buy the whole 488-acre post. Perry is scheduled take ownership of about 330 acres and MILRA, the authority, will retain the rest.

But a mix of government bureaucracy, environmental issues and a desire to quickly finish negotiations that started about a year ago have made it necessary for the city, authority officials and Perry’s team to find a different path forward, according to Councilwoman Joyce Sheperd, sponsor of the resolution.

Sheperd and MILRA executive director Brian Hooker said the city coffers won’t necessarily be tapped. Under the deal, Atlanta would only spend those funds if MILRA is unable to pay the U.S. Army the entire $26 million it’s asking for the land.

Using a portion of the $20 million Perry is expected to pay for the land this year, the authority will make a $13 million payment when it closes on the sale in coming months, with a second payment due in 2018, Hooker said.

Perry is expected pay the remaining $10 million after the Army cleans up and releases 22 environmentally troubled acres of land — a process that could be completed as early as next year, Hooker said.

If that land is not turned over by 2018, MILRA would need Atlanta to backstop the authority by purchasing $13 million worth of land on the Army post. That would allow MILRA to make its final payment to the Army.

The council could vote on the resolution as early as today, its first day back from spring recess.

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