The EPA and the city have spent decades cleaning up residential properties in east Omaha after a century of pollution from a lead smelter and other factories downtown. Before that, the EPA had been discussing expanding the Omaha cleanup, which could have included nearly 27,000 properties. March 1999 The Environmental Protection Agency began testing soil from Omaha yards after concerns about elevated blood lead levels in children. An Omaha lead smelter spread dust that seeped into the soil and bodies of many residents. Even when kids test high for lead, however, the city and the EPA don’t always retest yards.