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.

The purpose of the consultation is to identify any current groundwater use in the Motorola 52nd Street Superfund Site area that might result in human exposure to site contaminants. The Arizona Department of Health Services previously evaluated well use in Operable Units 1 and 2 in 1992. This report updates the well use inventory for Operable Units 1 and 2 and provides an evaluation of potential groundwater exposure pathways in Operable Unit 3.

The purpose of this health consultation is to determine whether contaminants in groundwater from the Motorola 56th Street facility represent a threat to public health. The facility was first occupied in the spring of 1950 as the Western Military Electronics Center. From 1950 to 1958, it was primarily used for bench type electronics, electronic assembly, and semiconductor production. The chemicals used in these processes included solvent degreasers such as trichloroethylene, acetone, and freon, and metals such as cadmium, chromium, and arsenic. From 1959 through 1961, the facility was used primarily for document storage. Beginning in 1962, manufacturing of electronics resumed to include assembly of circuit boards, plating, and degreasing. Chemicals used between 1962 and 1974 included trichloroethylene, tetrachloroethylene, and a number of acids and metals including arsenic. In 1975, the facility began manufacturing liquid crystal products. These activities continued until 1982, when it was converted to office use. The investigations that have been conducted to date have shown that there are residual levels of arsenic and fluoride in down-gradient private wells west of the facility. Solvent contaminants that were found in the 1980s are no longer present at detectable levels in down-gradient private wells.