By now it's no secret -- MARTA wants more sales tax money from Fulton, DeKalb and the city of Atlanta to help realize several future expansions.

MARTA's Board Chairman Robbie Ashe explains how an extra half-percent sales tax could be leveraged to provide $8 billion in additional funding for the transit agency over the next 40 years in a column today by AJC's Tom Sabulis highlighting MARTA's ground game for expansion.

That $8 billion would be enough money, Ashe said, to build a heavy rail expansion northward to Alpharetta and eastward to the Mall at Stonecrest, as well as a light rail connecting the Lindbergh and Avondale stations. He goes on to explain:

Assuming that those conversations go well, and they have so far, we will go to the 2016 General Assembly (and) ask them to permit our member jurisdictions to ask their voters for an additional half-penny sales tax that would last the duration of MARTA's existing penny (tax). That half-penny would go to finance these expansion projects. They would then roll (into) operations and maintenance once (the projects) are delivered."