The objective of this assessment is to evaluate whether a public health hazard exists as a result of environmental exposures in Hayden and Winkelman, Arizona, located near a smelter operated by ASARCO, Inc. Some of the residents of these towns have expressed concerns that metals from smelter emissions over the years have been causing health problems. This report uses environmental data collected from water, soil, and air in the Hayden and Winkelman area to estimate environmental exposures. The study also evaluates available health outcome data from previous epidemiological and biological-monitoring studies conducted in the area. The report concludes that exposure to sulfur dioxide occasionally poses a short-term public health hazard to sensitive asthmatics. These episodes of higher levels of sulfur dioxide occur infrequently. They do not appear to pose a health hazard to persons without sensitive airways or asthma. Other environmental exposures do not appear to pose a public health hazard.

In September 1999, the U.S. Environmental Protection Agency contacted the Arizona Department of Health Services, Office of Environmental Health, concerning potential contamination of private drinking water wells along Lynx Creek in the Walker, Arizona, mining district. Historical mining activities in the area might have resulted in contamination of groundwater by acid mine runoff as well as metals from extraction processes. EPA and ADHS determined the historical mining activity had caused environmental damage and the potential for adverse human health impacts. ADHS initiated a private well sampling program to determine if the mining activity has had an adverse impact on the quality of water from these wells. Several area residents have expressed concerns about their water quality. The objective of this public health consultation is to evaluate the potential for health effects from exposure to contaminants in private drinking water wells in the Walker, Arizona area.