This report presents an assessment of human health risks from exposure to surface soil metals in the Old Tungsten Mill, Tucson, AZ. City of Tucson officials had planned to build a park, on a parcel of land they owned west of Silverbell Road and north of Speedway Boulevard in Tucson, Pima County, Arizona. They had raised $200,000 in bond money to study what was the Old Tungsten Mill site when they found high levels of contaminants in the soil. The Arizona Department of Health Services, Risk Assessment & Health Consultation Program offered assistance to the city. On October 13th, 2006 City Officials asked ADHS to perform a health consultation to evaluate whether exposure to contaminants in soil pose a public health hazard, either currently or during possible future reuse of the land.

The Arizona Department of Health Services received a request for a Health Consultation from the City of Litchfield Park, dated March 5, 2007. The nature of the request was for ADHS to determine if there was a risk to public health from eating fish taken from Tierra Verde Lake. The City sponsors an annual fishing derby and believed that some citizens were eating the fish they caught. The City tested their lake water and for the very first time, measurable amounts of perchlorates were detected. The probable source for the perchlorates was thought to be from a groundwater, contaminant plume originating from the Phoenix Goodyear Airport Superfund Site.