When the Portland Alumnae chapter of the Delta Sigma Theta sorority purchased a long-abandoned gas station in east Portland in 1992, the idea was to use it as a meeting place. But it was a little dirty.

Correction: “It was nasty!” insists Aletha Chavis, a retired educator and Delta since 1951. “It was just awful — dirty and cobwebby and really grimy.”

Chavis didn’t know, then, that this grimy, dilapidated brownfield site would have a remarkable future as one of the greenest buildings in Portland.