After lengthy back and forth negotiations between Mayor Rahm Emanuel and the “green tech development company,” Emerald Living reached a point of sale agreement this week. The 440-acre lakefront property, formerly a U.S. Steel site, has remained vacant since the closing of its doors in 1992. Now nearly 30 years and many failed project attempts later Emerald is closing in on a deal to bring 20,000 homes to the area. A place where plant employees can afford to live, dine at their lakefront restaurants and enjoy a windmill farm designed to create clean energy for the community. While the new building plans sound like just what the area needs, Alderman Susan Sadlowski Garza (10th Ward) is skeptical. Similar plans have fallen through in the past, and with only a letter of intent to purchase, Emerald has five months to conduct an “environmental review” in which if something comes up the deal can be called off, no questions asked.