The Sierra Club has been pushing for a thorough cleanup of contaminated soils around the abandoned Colorado Smelter site, including notably parts of the Eilers and Bessemer neighborhoods in Pueblo. The Colorado Smelting Company began operations in 1883, and left a legacy that taxpayers will now have to undo. Questions over possible contamination from the site were raised in the 1990s and tests were conducted in 2010 by the Colorado Department of Public Health and Environment (CDPHE ). These tests showed areas of elevated lead and arsenic existed with some levels exceeding the EPA’s national screening guidelines for these contaminants.

Lead and arsenic can cause health problems to people who are exposed to them. Exposure to lead may cause nervous system damage, anemia, brain damage, cancer, or in extreme cases, even death. Children are especially susceptible to the toxic effects of lead. Exposure to arsenic can also cause a variety of health problems - it is a known carcinogen.

In 2011 the EPA and the CDPHE completed a site assessment that found elevated levels of lead and arsenic in residential soils and large slag piles in the Eilers neighborhood. After over a year of inaction, in 2013 the Sierra Club requested Pueblo City Council for a prompt decision to request the help of the only agency with the expertise and resources to conduct a thorough cleanup.

In 2014 the EPA proposed to add the former Colorado Smelter site to the National Priorities List of Superfund sites. They held a 60 day public comment period on the proposal, and officially added the site to the list in December 2014. Additional sampling will help determine the type and scope of cleanup activities.

The EPA has convened a Community Advisory Group (CAG) to advised them and the rest of the community on issues and concerns related to the cleanup. Its meetings are open to the public. For more information on dates, times and locations, visit the EPA's Colorado Smelter page.