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.

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.

In March 2004, a resident of Cornville contacted the Arizona Department of Environmental Quality to request information on arsenic in drinking water. The resident collected six well water samples from their own well and neighbors’ wells and submitted them to a private laboratory for arsenic analysis. The analyses detected arsenic ranging from 15 to 952 μg/L. ADEQ and the community members asked the Arizona Department of Health Services to provide health information about using the water. Initial conversations with the well owner and other community members revealed that many people had concerns about potential health effects from arsenic exposure.