It seems as though every member of Congress has a plan for tinkering with the tax code, to ease suburban sprawl and conserve natural resources. From promoting the reuse of Pennsylvania’s scarred mines to encouraging the development of abandoned urban industrial sites, known as brownfields, green fever is sweeping Capitol Hill.

“There’s a lot of concern among both Democrats and Republicans about urban sprawl,” said one senior congressional aide. “Suburban areas are moving farther and farther out. Farms and ranches are being developed.”